RE: Just when we think we are doing the right thing...

[Guest guest]

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the outcome?

Am I off base here or misinterpreting something? Maybe I am just being blonde

today instead of a redhead?

Jane Dinsmore

To: texasems-l ; Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

_________________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the outcome?

Am I off base here or misinterpreting something? Maybe I am just being blonde

today instead of a redhead?

Jane Dinsmore

To: texasems-l ; Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

_________________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l ;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l ;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l ;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Hmmm, so according to this study, even though the ETCO2 target range remained

the same, the correlation to actual PaCO2 was variable. Is that correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce the

study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l ;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Hmmm, so according to this study, even though the ETCO2 target range remained

the same, the correlation to actual PaCO2 was variable. Is that correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce the

study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l ;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Hmmm, so according to this study, even though the ETCO2 target range remained

the same, the correlation to actual PaCO2 was variable. Is that correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce the

study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l ;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Yeah bummer. However, I will sit back patiently and see if someone will

reproduce this study to validate it before I jump to hastily here. I hope

someone will.

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 13:05:09 -0600

Subject: RE: Just when we think we are doing the right thing...

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l [mailto:texasems-l ] On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Oops!

Should read, " I think there is a significant role for capnography. But, it

probably should NOT be used to guide ventilation in severe

trauma victims. " I left out the " not " !

From: texasems-l [mailto:texasems-l ] On

Behalf Of Bledsoe, DO

Sent: Sunday, February 22, 2009 1:05 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l

]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Oops!

Should read, " I think there is a significant role for capnography. But, it

probably should NOT be used to guide ventilation in severe

trauma victims. " I left out the " not " !

From: texasems-l [mailto:texasems-l ] On

Behalf Of Bledsoe, DO

Sent: Sunday, February 22, 2009 1:05 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l

]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Oops!

Should read, " I think there is a significant role for capnography. But, it

probably should NOT be used to guide ventilation in severe

trauma victims. " I left out the " not " !

From: texasems-l [mailto:texasems-l ] On

Behalf Of Bledsoe, DO

Sent: Sunday, February 22, 2009 1:05 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l

]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

Good save. LOL

Jane

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 13:18:43 -0600

Subject: RE: Just when we think we are doing the right thing...

Oops!

Should read, " I think there is a significant role for capnography. But, it

probably should NOT be used to guide ventilation in severe

trauma victims. " I left out the " not " !

From: texasems-l [mailto:texasems-l ] On

Behalf Of Bledsoe, DO

Sent: Sunday, February 22, 2009 1:05 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

It is the first I have seen and it was submitted 9/08. The theory, and

probably fact, is that the correlation studies of ETCO2 and PCO2 were done

on healthy people. Those with injury and illness have abnormal ventilatory

capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

the less likely ETCO2 is accurate. I think there is a significant role for

capnography. But, it probably should be used to guide ventilation in severe

trauma victims. I think all EMS patients should be put on a mechanical

ventilator as soon as practical to assure accurate respiratory rate and

depth. The costs of the various transport vents is coming down.

Bummer eh?

BEB

From: texasems-l

[mailto:texasems-l ]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:52 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

Hmmm, so according to this study, even though the ETCO2 target range

remained the same, the correlation to actual PaCO2 was variable. Is that

correct?

Interesting. Have you heard yet if anyone is going to attempt to reproduce

the study or if this is a reproduction of another study to validate it?

Jane Dinsmore

To: texasems-l

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:40:27 -0600

Subject: RE: Just when we think we are doing the right thing...

You have to look at the whole paper. The EtCO2 readings were all over the

place compared to the PCO2. The target makes little difference as the ETCO2

readings at all values correlated poorly with PCO2 values. It is a fairly

rigorous study.

BEB

From: texasems-l

[mailto:texasems-l

]

On

Behalf Of Jane Dinsmore

Sent: Sunday, February 22, 2009 12:36 PM

To: texasems-l

Subject: RE: Just when we think we are doing the right thing...

If I am not mistaken, many ETCO2 advocates usually use the target range of

30-35, not 35 to 40 (except in brain herniation syndrome in which the target

range recommended is actually lower than that), due to a known correlative

variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

target range for the study (instead of the one chosen) have changed the

outcome? Am I off base here or misinterpreting something? Maybe I am just

being blonde today instead of a redhead?

Jane Dinsmore

To: texasems-l

;

Paramedicine

From: bbledsoe@...

Date: Sun, 22 Feb 2009 12:02:06 -0600

Subject: Just when we think we are doing the right thing...

Trauma. 2009 Jan;66(1):26-31.

The utility of early end-tidal capnography in monitoring ventilation status

after severe injury.

Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

GJ, Bulger EM.

Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

98104, USA. keirw@...

BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

to be the ideal target range for early ventilation in trauma patients;

however, this requires serial arterial blood gases. The use of end-tidal

capnography (EtCO2) has been recommended as a surrogate measure of

ventilation in the prehospital arena. This is based on the observation of

close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

hypothesize that EtCO2 will demonstrate a poor reflection of actual

ventilation status after severe injury.

METHODS: Prospective observational study on consecutive intubated trauma

patients treated in our emergency department (ED) during 9 months. Arterial

blood gas values and concomitant EtCO2 levels were recorded. Regression was

used to determine the strength of correlation among all trauma patients and

subgroups based on injury severity (Abbreviated Injury Score and Injury

Severity Score) and physiologic markers of perfusion status (lactate, shock

index, and arterial base deficit).

RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

correlation was poor at R2 = 0.277. Patients ventilated in the recommended

EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

of the time. Correlation was best for patients with isolated traumatic brain

injury and worst for those with evidence of poor tissue perfusion.

CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

be used to guide ventilation in intubated trauma patients in the ED. Better

strategies for guiding prehospital and ED ventilation are needed.

__________________________________________________________

Access your email online and on the go with Windows Live Hotmail.

http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

[Guest guest]

There was some discussion about this study this weekend at the Eagles

conference by the group, - including Dr. Copass one of the authors.

Much was made out of the sick vs healthy person results and a lot of

discussion regarding the variance.

Would be interesting if the results were reproduced.

AJL

On Sun, Feb 22, 2009 at 1:18 PM, Bledsoe, DO

bbledsoe@...> wrote:

> Oops!

>

> Should read, " I think there is a significant role for capnography. But, it

> probably should NOT be used to guide ventilation in severe

> trauma victims. " I left out the " not " !

>

> From: texasems-l [mailto:texasems-l ] On

> Behalf Of Bledsoe, DO

> Sent: Sunday, February 22, 2009 1:05 PM

> To: texasems-l

> Subject: RE: Just when we think we are doing the right thing...

>

> It is the first I have seen and it was submitted 9/08. The theory, and

> probably fact, is that the correlation studies of ETCO2 and PCO2 were done

> on healthy people. Those with injury and illness have abnormal ventilatory

> capacity and ventilation/perfusion mismatch. Thus, the sicker the patient,

> the less likely ETCO2 is accurate. I think there is a significant role for

> capnography. But, it probably should be used to guide ventilation in severe

> trauma victims. I think all EMS patients should be put on a mechanical

> ventilator as soon as practical to assure accurate respiratory rate and

> depth. The costs of the various transport vents is coming down.

>

> Bummer eh?

>

> BEB

>

> From: texasems-l

> [mailto:texasems-l ]

> On

> Behalf Of Jane Dinsmore

> Sent: Sunday, February 22, 2009 12:52 PM

> To: texasems-l

> Subject: RE: Just when we think we are doing the right thing...

>

> Hmmm, so according to this study, even though the ETCO2 target range

> remained the same, the correlation to actual PaCO2 was variable. Is that

> correct?

>

> Interesting. Have you heard yet if anyone is going to attempt to reproduce

> the study or if this is a reproduction of another study to validate it?

>

> Jane Dinsmore

>

> To: texasems-l

>

> From: bbledsoe@...

>

> Date: Sun, 22 Feb 2009 12:40:27 -0600

> Subject: RE: Just when we think we are doing the right thing...

>

> You have to look at the whole paper. The EtCO2 readings were all over the

> place compared to the PCO2. The target makes little difference as the ETCO2

> readings at all values correlated poorly with PCO2 values. It is a fairly

> rigorous study.

>

> BEB

>

> From: texasems-l

>

> [mailto:texasems-l

> ]

> On

> Behalf Of Jane Dinsmore

> Sent: Sunday, February 22, 2009 12:36 PM

> To: texasems-l

>

> Subject: RE: Just when we think we are doing the right thing...

>

> If I am not mistaken, many ETCO2 advocates usually use the target range of

> 30-35, not 35 to 40 (except in brain herniation syndrome in which the target

> range recommended is actually lower than that), due to a known correlative

> variation between ETCO2 and PaCO2. If that is the case, wouldn't using THAT

> target range for the study (instead of the one chosen) have changed the

> outcome? Am I off base here or misinterpreting something? Maybe I am just

> being blonde today instead of a redhead?

>

> Jane Dinsmore

>

> To: texasems-l

>

> ;

> Paramedicine

>

>

> From: bbledsoe@...

>

>

> Date: Sun, 22 Feb 2009 12:02:06 -0600

> Subject: Just when we think we are doing the right thing...

>

> Trauma. 2009 Jan;66(1):26-31.

>

> The utility of early end-tidal capnography in monitoring ventilation status

> after severe injury.

>

> Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich

> GJ, Bulger EM.

> Department of Trauma Surgery, Harborview Medical Center, Seattle, Washington

> 98104, USA. keirw@...

>

>

>

> BACKGROUND: An arterial CO2 (PaCO2) of 30 mm Hg to 39 mm Hg has been shown

> to be the ideal target range for early ventilation in trauma patients;

> however, this requires serial arterial blood gases. The use of end-tidal

> capnography (EtCO2) has been recommended as a surrogate measure of

> ventilation in the prehospital arena. This is based on the observation of

> close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients

> frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we

> hypothesize that EtCO2 will demonstrate a poor reflection of actual

> ventilation status after severe injury.

>

> METHODS: Prospective observational study on consecutive intubated trauma

> patients treated in our emergency department (ED) during 9 months. Arterial

> blood gas values and concomitant EtCO2 levels were recorded. Regression was

> used to determine the strength of correlation among all trauma patients and

> subgroups based on injury severity (Abbreviated Injury Score and Injury

> Severity Score) and physiologic markers of perfusion status (lactate, shock

> index, and arterial base deficit).

>

> RESULTS: During 9 months, 180 patients were evaluated. The EtCO2 Paco2

> correlation was poor at R2 = 0.277. Patients ventilated in the recommended

> EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm

> Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30%

> of the time. Correlation was best for patients with isolated traumatic brain

> injury and worst for those with evidence of poor tissue perfusion.

>

> CONCLUSION: EtCO2 has low correlation with Pa(CO2), and therefore should not

> be used to guide ventilation in intubated trauma patients in the ED. Better

> strategies for guiding prehospital and ED ventilation are needed.

>

> __________________________________________________________

> Access your email online and on the go with Windows Live Hotmail.

> http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Access_022009

>

>