Re: Question regarding fluid resuscitation

[Guest guest]

,

There comes a point at which a patient needs blood. Period. I don't know how

low hematocrit can go and still be adequate to perfuse the brain. Anybody care

to comment on that? Of course, there are vasopressors, but my motto is don't

give a vasopressor to an empty tank.

Gene

Re: Question regarding fluid resuscitation

Gene,

I, as a practicing paramedic, did not get taught this; but I am glad you are

bringing it up. My question is in the situation of a trauma patient with severe

volume loss and only fluid on hand, will the increase in CPP by fluid

resuscitation be sufficient to perfuse the brain with the reduction in oxygen

carrying capacity as the circulating volume is diluted? It is possible to raise

pressure without increasing perfusion. Is there a happy medium, or should we

consider carrying other volume expanders?

Perhaps this would be an argument for the continued use of PASGs? Just a

thought.

Sent from my iPhone

McGee, EMT-P

> For the last few years, fluid resuscitation of trauma patients has been aimed

at maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

hypotension " based upon hydrostatic concerns about the effects of heightened

hydrostatic pressures in the fact of internal bleeding. It has been postulated

that increased hydrostatic pressures will dislodge clots that have been formed

as a natural response to injury, and that increased fluid volumes will dilute

clotting factors and lead to increased bleeding. These concepts are valid.

>

> However, I propose that this concept fails to take into consideration one

vital aspect of trauma care, that of adequate perfusion of the brain. Cerebral

perfusion pressure (CPP) is the measure of brain perfusion, and it must be

maintained at a level of 80 mm Hg or better. Studies show that when a patient's

CPP is maintained at that level, there is a 35% improvement in outcomes, whereas

lower CPPs result in poorer outcomes.

>

> There are two components of blood pressure: the systolic and diastolic

readings. Systolic pressure represents hydrostatic pressure, and diastolic

pressure represents the degree of vasoconstriction. This is an

oversimplification, but it is

>

> basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

not insure adequate CPP.

>

> In order to figure CPP, one must first determine mean arterial pressure (MAP)

and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

monitored in the field, but can be estimated based upon clinical observations.

>

> The formula for CPP is this: CPP = MAP - ICP.

>

> MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of 60.

One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

MAP of 100.

>

> Normal patients without head injuries, at rest, have an ICP of from around 5

to 15 mm Hg. This can vary depending upon posture. For example, if a patient who

is supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy or even faint. Conversely, when one coughs or sneezes, ICP spikes, but

only for a few seconds.

>

> With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3 pulse

pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

>

> Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In

fact, a CPP of 53 is close to the limit for survival.

>

> And this is in a patient without a head injury. Given a patient with rising

intracranial pressure, it becomes obvious that a higher MAP is needed to

adequately perfuse the brain.

>

> These concepts are taught in the traumatic brain injury courses, but not

emphasized, I fear, in paramedic training.

>

> So my question is this: How many of you who are EMS educators use this in your

teaching? How many of you who are Paramedics have had this training and

understand these concepts?

>

> Are we doing enough to educate our medics to the basics of brain perfusion

with the current guidelines about fluid resuscitation?

>

> Gene Gandy, JD, LP, NREMTP

> PERCOMONLINE.COM

> Tucson, AZ

>

> .

>

>

[Guest guest]

Gene,

We did learn this in school (grad Dec ’09) but not sure how much I have

retained since then. I’d love to see some type of CE on it.

Toni

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

Of lawrence verrett

Sent: Tuesday, June 28, 2011 9:43 AM

To: texasems-l

Subject: Re: Question regarding fluid resuscitation

Gene. I have heard of this before, and did learn it many years ago, but I have

not seen it tough in a few years to be sure. In my paramedic class in the late

80's we did not even talk about it.

________________________________

From: Wegandy wegandy@... >

To: texasems-l

Sent: Tue, June 28, 2011 4:54:58 AM

Subject: Question regarding fluid resuscitation

For the last few years, fluid resuscitation of trauma patients has been aimed at

maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

hypotension " based upon hydrostatic concerns about the effects of heightened

hydrostatic pressures in the fact of internal bleeding. It has been postulated

that increased hydrostatic pressures will dislodge clots that have been formed

as a natural response to injury, and that increased fluid volumes will dilute

clotting factors and lead to increased bleeding. These concepts are valid.

However, I propose that this concept fails to take into consideration one vital

aspect of trauma care, that of adequate perfusion of the brain. Cerebral

perfusion pressure (CPP) is the measure of brain perfusion, and it must be

maintained at a level of 80 mm Hg or better. Studies show that when a patient's

CPP is maintained at that level, there is a 35% improvement in outcomes, whereas

lower CPPs result in poorer outcomes.

There are two components of blood pressure: the systolic and diastolic readings.

Systolic pressure represents hydrostatic pressure, and diastolic pressure

represents the degree of vasoconstriction. This is an oversimplification, but it

is

basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

not insure adequate CPP.

In order to figure CPP, one must first determine mean arterial pressure (MAP)

and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

monitored in the field, but can be estimated based upon clinical observations.

The formula for CPP is this: CPP = MAP - ICP.

MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of 60.

One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

MAP of 100.

Normal patients without head injuries, at rest, have an ICP of from around 5 to

15 mm Hg. This can vary depending upon posture. For example, if a patient who is

supine suddenly stands up, his ICP will fall, and if he is dehydrated or taking

antihypertensives that antagonize alpha-1 vasoconstriction, he can become dizzy

or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only for

a few seconds.

With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3 pulse

pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg, then

MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

CPP of 53 is close to the limit for survival.

And this is in a patient without a head injury. Given a patient with rising

intracranial pressure, it becomes obvious that a higher MAP is needed to

adequately perfuse the brain.

These concepts are taught in the traumatic brain injury courses, but not

emphasized, I fear, in paramedic training.

So my question is this: How many of you who are EMS educators use this in your

teaching? How many of you who are Paramedics have had this training and

understand these concepts?

Are we doing enough to educate our medics to the basics of brain perfusion with

the current guidelines about fluid resuscitation?

Gene Gandy, JD, LP, NREMTP

PERCOMONLINE.COM

Tucson, AZ

..

[Guest guest]

Don could it be the NSC and EMS Education Standards don't reflect cutting edge

medicine.

Just saying.

Louis N. Molino, Sr. CET

FF/NREMT/FSI/EMSI

Training Program Manager

Fire & Safety Specialists, Inc.

Typed by my fingers on my iPhone.

Please excuse any typos.

(Cell)

(Office)

(Office Fax)

LNMolino@...

Lou@...

> Gene,

> While that is not in the text I/we use for our medic courses (which is Brady)

......which tells us that it's not in the NSC.....it has been taught in ITLS now

for some time and for that reason is taught in our medic classes. As you point

out, the theory explains the reason for targeting a somewhat higher systolic in

a hypotensive patient with a CHI, which is also part of our protocols. I suppose

this is becoming more common to EMS protocols hopefully everywhere (?). And I

would presume this is also taught in PHTLS (?). A good question to ask sir.

>

> Don,

> Tyler

>

>

>

>

> ________________________________

> From: Wegandy wegandy@... >

> To: texasems-l

> Sent: Tue, June 28, 2011 4:54:58 AM

> Subject: Question regarding fluid resuscitation

>

> For the last few years, fluid resuscitation of trauma patients has been aimed

at

> maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

> hypotension " based upon hydrostatic concerns about the effects of heightened

> hydrostatic pressures in the fact of internal bleeding. It has been postulated

> that increased hydrostatic pressures will dislodge clots that have been formed

> as a natural response to injury, and that increased fluid volumes will dilute

> clotting factors and lead to increased bleeding. These concepts are valid.

>

> However, I propose that this concept fails to take into consideration one

vital

> aspect of trauma care, that of adequate perfusion of the brain. Cerebral

> perfusion pressure (CPP) is the measure of brain perfusion, and it must be

> maintained at a level of 80 mm Hg or better. Studies show that when a

patient's

> CPP is maintained at that level, there is a 35% improvement in outcomes,

whereas

> lower CPPs result in poorer outcomes.

>

> There are two components of blood pressure: the systolic and diastolic

readings.

> Systolic pressure represents hydrostatic pressure, and diastolic pressure

> represents the degree of vasoconstriction. This is an oversimplification, but

it

> is

>

> basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

> not insure adequate CPP.

>

> In order to figure CPP, one must first determine mean arterial pressure (MAP)

> and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

> monitored in the field, but can be estimated based upon clinical observations.

>

> The formula for CPP is this: CPP = MAP - ICP.

>

> MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

> pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of

60.

> One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

> MAP of 100.

>

> Normal patients without head injuries, at rest, have an ICP of from around 5

to

> 15 mm Hg. This can vary depending upon posture. For example, if a patient who

is

> supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking

> antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy

> or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only

for

> a few seconds.

>

> With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

> fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3

pulse

> pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

>

> Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then

> MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

> CPP of 53 is close to the limit for survival.

>

> And this is in a patient without a head injury. Given a patient with rising

> intracranial pressure, it becomes obvious that a higher MAP is needed to

> adequately perfuse the brain.

>

> These concepts are taught in the traumatic brain injury courses, but not

> emphasized, I fear, in paramedic training.

>

> So my question is this: How many of you who are EMS educators use this in your

> teaching? How many of you who are Paramedics have had this training and

> understand these concepts?

>

> Are we doing enough to educate our medics to the basics of brain perfusion

with

> the current guidelines about fluid resuscitation?

>

> Gene Gandy, JD, LP, NREMTP

> PERCOMONLINE.COM

> Tucson, AZ

>

> .

>

>

[Guest guest]

Don could it be the NSC and EMS Education Standards don't reflect cutting edge

medicine.

Just saying.

Louis N. Molino, Sr. CET

FF/NREMT/FSI/EMSI

Training Program Manager

Fire & Safety Specialists, Inc.

Typed by my fingers on my iPhone.

Please excuse any typos.

(Cell)

(Office)

(Office Fax)

LNMolino@...

Lou@...

> Gene,

> While that is not in the text I/we use for our medic courses (which is Brady)

......which tells us that it's not in the NSC.....it has been taught in ITLS now

for some time and for that reason is taught in our medic classes. As you point

out, the theory explains the reason for targeting a somewhat higher systolic in

a hypotensive patient with a CHI, which is also part of our protocols. I suppose

this is becoming more common to EMS protocols hopefully everywhere (?). And I

would presume this is also taught in PHTLS (?). A good question to ask sir.

>

> Don,

> Tyler

>

>

>

>

> ________________________________

> From: Wegandy wegandy@... >

> To: texasems-l

> Sent: Tue, June 28, 2011 4:54:58 AM

> Subject: Question regarding fluid resuscitation

>

> For the last few years, fluid resuscitation of trauma patients has been aimed

at

> maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

> hypotension " based upon hydrostatic concerns about the effects of heightened

> hydrostatic pressures in the fact of internal bleeding. It has been postulated

> that increased hydrostatic pressures will dislodge clots that have been formed

> as a natural response to injury, and that increased fluid volumes will dilute

> clotting factors and lead to increased bleeding. These concepts are valid.

>

> However, I propose that this concept fails to take into consideration one

vital

> aspect of trauma care, that of adequate perfusion of the brain. Cerebral

> perfusion pressure (CPP) is the measure of brain perfusion, and it must be

> maintained at a level of 80 mm Hg or better. Studies show that when a

patient's

> CPP is maintained at that level, there is a 35% improvement in outcomes,

whereas

> lower CPPs result in poorer outcomes.

>

> There are two components of blood pressure: the systolic and diastolic

readings.

> Systolic pressure represents hydrostatic pressure, and diastolic pressure

> represents the degree of vasoconstriction. This is an oversimplification, but

it

> is

>

> basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

> not insure adequate CPP.

>

> In order to figure CPP, one must first determine mean arterial pressure (MAP)

> and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

> monitored in the field, but can be estimated based upon clinical observations.

>

> The formula for CPP is this: CPP = MAP - ICP.

>

> MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

> pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of

60.

> One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

> MAP of 100.

>

> Normal patients without head injuries, at rest, have an ICP of from around 5

to

> 15 mm Hg. This can vary depending upon posture. For example, if a patient who

is

> supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking

> antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy

> or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only

for

> a few seconds.

>

> With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

> fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3

pulse

> pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

>

> Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then

> MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

> CPP of 53 is close to the limit for survival.

>

> And this is in a patient without a head injury. Given a patient with rising

> intracranial pressure, it becomes obvious that a higher MAP is needed to

> adequately perfuse the brain.

>

> These concepts are taught in the traumatic brain injury courses, but not

> emphasized, I fear, in paramedic training.

>

> So my question is this: How many of you who are EMS educators use this in your

> teaching? How many of you who are Paramedics have had this training and

> understand these concepts?

>

> Are we doing enough to educate our medics to the basics of brain perfusion

with

> the current guidelines about fluid resuscitation?

>

> Gene Gandy, JD, LP, NREMTP

> PERCOMONLINE.COM

> Tucson, AZ

>

> .

>

>

[Guest guest]

Blasphemy

Sent from my iPhone

McGee, EMT-P

> Don could it be the NSC and EMS Education Standards don't reflect cutting edge

medicine.

>

> Just saying.

>

> Louis N. Molino, Sr. CET

> FF/NREMT/FSI/EMSI

> Training Program Manager

> Fire & Safety Specialists, Inc.

> Typed by my fingers on my iPhone.

> Please excuse any typos.

> (Cell)

> (Office)

> (Office Fax)

>

> LNMolino@...

> Lou@...

>

>

>

> > Gene,

> > While that is not in the text I/we use for our medic courses (which is

Brady) .....which tells us that it's not in the NSC.....it has been taught in

ITLS now for some time and for that reason is taught in our medic classes. As

you point out, the theory explains the reason for targeting a somewhat higher

systolic in a hypotensive patient with a CHI, which is also part of our

protocols. I suppose this is becoming more common to EMS protocols hopefully

everywhere (?). And I would presume this is also taught in PHTLS (?). A good

question to ask sir.

> >

> > Don,

> > Tyler

> >

> >

> >

> >

> > ________________________________

> > From: Wegandy wegandy@... >

> > To: texasems-l

> > Sent: Tue, June 28, 2011 4:54:58 AM

> > Subject: Question regarding fluid resuscitation

> >

> > For the last few years, fluid resuscitation of trauma patients has been

aimed at

> > maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

> > hypotension " based upon hydrostatic concerns about the effects of heightened

> > hydrostatic pressures in the fact of internal bleeding. It has been

postulated

> > that increased hydrostatic pressures will dislodge clots that have been

formed

> > as a natural response to injury, and that increased fluid volumes will

dilute

> > clotting factors and lead to increased bleeding. These concepts are valid.

> >

> > However, I propose that this concept fails to take into consideration one

vital

> > aspect of trauma care, that of adequate perfusion of the brain. Cerebral

> > perfusion pressure (CPP) is the measure of brain perfusion, and it must be

> > maintained at a level of 80 mm Hg or better. Studies show that when a

patient's

> > CPP is maintained at that level, there is a 35% improvement in outcomes,

whereas

> > lower CPPs result in poorer outcomes.

> >

> > There are two components of blood pressure: the systolic and diastolic

readings.

> > Systolic pressure represents hydrostatic pressure, and diastolic pressure

> > represents the degree of vasoconstriction. This is an oversimplification,

but it

> > is

> >

> > basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg

does

> > not insure adequate CPP.

> >

> > In order to figure CPP, one must first determine mean arterial pressure

(MAP)

> > and estimate the intracranial pressure (ICP). Intracranial pressure cannot

be

> > monitored in the field, but can be estimated based upon clinical

observations.

> >

> > The formula for CPP is this: CPP = MAP - ICP.

> >

> > MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

> > pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of

60.

> > One-third of 60 is 20, and added to the diastolic pressure of 80, results in

a

> > MAP of 100.

> >

> > Normal patients without head injuries, at rest, have an ICP of from around 5

to

> > 15 mm Hg. This can vary depending upon posture. For example, if a patient

who is

> > supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking

> > antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy

> > or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only

for

> > a few seconds.

> >

> > With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

> > fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3

pulse

> > pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

> >

> > Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then

> > MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact,

a

> > CPP of 53 is close to the limit for survival.

> >

> > And this is in a patient without a head injury. Given a patient with rising

> > intracranial pressure, it becomes obvious that a higher MAP is needed to

> > adequately perfuse the brain.

> >

> > These concepts are taught in the traumatic brain injury courses, but not

> > emphasized, I fear, in paramedic training.

> >

> > So my question is this: How many of you who are EMS educators use this in

your

> > teaching? How many of you who are Paramedics have had this training and

> > understand these concepts?

> >

> > Are we doing enough to educate our medics to the basics of brain perfusion

with

> > the current guidelines about fluid resuscitation?

> >

> > Gene Gandy, JD, LP, NREMTP

> > PERCOMONLINE.COM

> > Tucson, AZ

> >

> > .

> >

> >

[Guest guest]

Lou,

I don't know that I'd say that necessarily. 'Cutting edge' concepts, if that's

what we're talking about, always stay ahead of curriculum development. And

that's the natural order of things. But....on the other hand....the concept Gene

is speaking of is not a totally brand new one. I think the better question is if

this concept has been bought off on by EMS medical directors and others who

affect EMS protocols. One might guess that, because the prognosis is so poor for

someone shocky and has cerebral swelling, that a lot of physicians believe that

it makes no difference in outcome. Career experiences are the strongest

influencers of opinion. But, to me and my little humble opinion, it seems to

make sense.

Don

>>> " Louis N. Molino, Sr. " lnmolino@...> 6/29/2011 12:26 PM >>>

Don could it be the NSC and EMS Education Standards don't reflect cutting edge

medicine.

Just saying.

Louis N. Molino, Sr. CET

FF/NREMT/FSI/EMSI

Training Program Manager

Fire & Safety Specialists, Inc.

Typed by my fingers on my iPhone.

Please excuse any typos.

(Cell)

(Office)

(Office Fax)

LNMolino@...

Lou@...

> Gene,

> While that is not in the text I/we use for our medic courses (which is Brady)

......which tells us that it's not in the NSC.....it has been taught in ITLS now

for some time and for that reason is taught in our medic classes. As you point

out, the theory explains the reason for targeting a somewhat higher systolic in

a hypotensive patient with a CHI, which is also part of our protocols. I suppose

this is becoming more common to EMS protocols hopefully everywhere (?). And I

would presume this is also taught in PHTLS (?). A good question to ask sir.

>

> Don,

> Tyler

>

>

>

>

> ________________________________

> From: Wegandy wegandy@... >

> To: texasems-l

> Sent: Tue, June 28, 2011 4:54:58 AM

> Subject: Question regarding fluid resuscitation

>

> For the last few years, fluid resuscitation of trauma patients has been aimed

at

> maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

> hypotension " based upon hydrostatic concerns about the effects of heightened

> hydrostatic pressures in the fact of internal bleeding. It has been postulated

> that increased hydrostatic pressures will dislodge clots that have been formed

> as a natural response to injury, and that increased fluid volumes will dilute

> clotting factors and lead to increased bleeding. These concepts are valid.

>

> However, I propose that this concept fails to take into consideration one

vital

> aspect of trauma care, that of adequate perfusion of the brain. Cerebral

> perfusion pressure (CPP) is the measure of brain perfusion, and it must be

> maintained at a level of 80 mm Hg or better. Studies show that when a

patient's

> CPP is maintained at that level, there is a 35% improvement in outcomes,

whereas

> lower CPPs result in poorer outcomes.

>

> There are two components of blood pressure: the systolic and diastolic

readings.

> Systolic pressure represents hydrostatic pressure, and diastolic pressure

> represents the degree of vasoconstriction. This is an oversimplification, but

it

> is

>

> basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

> not insure adequate CPP.

>

> In order to figure CPP, one must first determine mean arterial pressure (MAP)

> and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

> monitored in the field, but can be estimated based upon clinical observations.

>

> The formula for CPP is this: CPP = MAP - ICP.

>

> MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

> pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of

60.

> One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

> MAP of 100.

>

> Normal patients without head injuries, at rest, have an ICP of from around 5

to

> 15 mm Hg. This can vary depending upon posture. For example, if a patient who

is

> supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking

> antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy

> or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only

for

> a few seconds.

>

> With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

> fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3

pulse

> pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

>

> Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then

> MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

> CPP of 53 is close to the limit for survival.

>

> And this is in a patient without a head injury. Given a patient with rising

> intracranial pressure, it becomes obvious that a higher MAP is needed to

> adequately perfuse the brain.

>

> These concepts are taught in the traumatic brain injury courses, but not

> emphasized, I fear, in paramedic training.

>

> So my question is this: How many of you who are EMS educators use this in your

> teaching? How many of you who are Paramedics have had this training and

> understand these concepts?

>

> Are we doing enough to educate our medics to the basics of brain perfusion

with

> the current guidelines about fluid resuscitation?

>

> Gene Gandy, JD, LP, NREMTP

> PERCOMONLINE.COM

> Tucson, AZ

>

> .

>

>

[Guest guest]

If you look at the Guidelines for the Prehospital care of TBI’s from the Brain

Trauma Foundation you will find that this has been the recommendation since

1994.

Lee

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

Of Don Elbert

Sent: Wednesday, June 29, 2011 12:55 PM

Subject: Re: Question regarding fluid resuscitation

Lou,

I don't know that I'd say that necessarily. 'Cutting edge' concepts, if that's

what we're talking about, always stay ahead of curriculum development. And

that's the natural order of things. But....on the other hand....the concept Gene

is speaking of is not a totally brand new one. I think the better question is if

this concept has been bought off on by EMS medical directors and others who

affect EMS protocols. One might guess that, because the prognosis is so poor for

someone shocky and has cerebral swelling, that a lot of physicians believe that

it makes no difference in outcome. Career experiences are the strongest

influencers of opinion. But, to me and my little humble opinion, it seems to

make sense.

Don

>>> " Louis N. Molino, Sr. " lnmolino@... >

6/29/2011 12:26 PM >>>

Don could it be the NSC and EMS Education Standards don't reflect cutting edge

medicine.

Just saying.

Louis N. Molino, Sr. CET

FF/NREMT/FSI/EMSI

Training Program Manager

Fire & Safety Specialists, Inc.

Typed by my fingers on my iPhone.

Please excuse any typos.

(Cell)

(Office)

(Office Fax)

LNMolino@...

Lou@...

On Jun 29, 2011, at 10:09, " Don Elbert " delbert@...

> wrote:

> Gene,

> While that is not in the text I/we use for our medic courses (which is Brady)

......which tells us that it's not in the NSC.....it has been taught in ITLS now

for some time and for that reason is taught in our medic classes. As you point

out, the theory explains the reason for targeting a somewhat higher systolic in

a hypotensive patient with a CHI, which is also part of our protocols. I suppose

this is becoming more common to EMS protocols hopefully everywhere (?). And I

would presume this is also taught in PHTLS (?). A good question to ask sir.

>

> Don,

> Tyler

>

>

>

>

> ________________________________

> From: Wegandy wegandy@...

>

> To: texasems-l

> Sent: Tue, June 28, 2011 4:54:58 AM

> Subject: Question regarding fluid resuscitation

>

> For the last few years, fluid resuscitation of trauma patients has been aimed

at

> maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

> hypotension " based upon hydrostatic concerns about the effects of heightened

> hydrostatic pressures in the fact of internal bleeding. It has been postulated

> that increased hydrostatic pressures will dislodge clots that have been formed

> as a natural response to injury, and that increased fluid volumes will dilute

> clotting factors and lead to increased bleeding. These concepts are valid.

>

> However, I propose that this concept fails to take into consideration one

vital

> aspect of trauma care, that of adequate perfusion of the brain. Cerebral

> perfusion pressure (CPP) is the measure of brain perfusion, and it must be

> maintained at a level of 80 mm Hg or better. Studies show that when a

patient's

> CPP is maintained at that level, there is a 35% improvement in outcomes,

whereas

> lower CPPs result in poorer outcomes.

>

> There are two components of blood pressure: the systolic and diastolic

readings.

> Systolic pressure represents hydrostatic pressure, and diastolic pressure

> represents the degree of vasoconstriction. This is an oversimplification, but

it

> is

>

> basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

> not insure adequate CPP.

>

> In order to figure CPP, one must first determine mean arterial pressure (MAP)

> and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

> monitored in the field, but can be estimated based upon clinical observations.

>

> The formula for CPP is this: CPP = MAP - ICP.

>

> MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

> pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of

60.

> One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

> MAP of 100.

>

> Normal patients without head injuries, at rest, have an ICP of from around 5

to

> 15 mm Hg. This can vary depending upon posture. For example, if a patient who

is

> supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking

> antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy

> or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only

for

> a few seconds.

>

> With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

> fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3

pulse

> pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

>

> Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then

> MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

> CPP of 53 is close to the limit for survival.

>

> And this is in a patient without a head injury. Given a patient with rising

> intracranial pressure, it becomes obvious that a higher MAP is needed to

> adequately perfuse the brain.

>

> These concepts are taught in the traumatic brain injury courses, but not

> emphasized, I fear, in paramedic training.

>

> So my question is this: How many of you who are EMS educators use this in your

> teaching? How many of you who are Paramedics have had this training and

> understand these concepts?

>

> Are we doing enough to educate our medics to the basics of brain perfusion

with

> the current guidelines about fluid resuscitation?

>

> Gene Gandy, JD, LP, NREMTP

> PERCOMONLINE.COM

> Tucson, AZ

>

> .

>

>

[Guest guest]

Toni,

It pretty much boils down to what I wrote below. Not a whole lot to add.

Gene

Question regarding fluid resuscitation

For the last few years, fluid resuscitation of trauma patients has been aimed at

maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

hypotension " based upon hydrostatic concerns about the effects of heightened

hydrostatic pressures in the fact of internal bleeding. It has been postulated

that increased hydrostatic pressures will dislodge clots that have been formed

as a natural response to injury, and that increased fluid volumes will dilute

clotting factors and lead to increased bleeding. These concepts are valid.

However, I propose that this concept fails to take into consideration one vital

aspect of trauma care, that of adequate perfusion of the brain. Cerebral

perfusion pressure (CPP) is the measure of brain perfusion, and it must be

maintained at a level of 80 mm Hg or better. Studies show that when a patient's

CPP is maintained at that level, there is a 35% improvement in outcomes, whereas

lower CPPs result in poorer outcomes.

There are two components of blood pressure: the systolic and diastolic readings.

Systolic pressure represents hydrostatic pressure, and diastolic pressure

represents the degree of vasoconstriction. This is an oversimplification, but it

is

basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

not insure adequate CPP.

In order to figure CPP, one must first determine mean arterial pressure (MAP)

and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

monitored in the field, but can be estimated based upon clinical observations.

The formula for CPP is this: CPP = MAP - ICP.

MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of 60.

One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

MAP of 100.

Normal patients without head injuries, at rest, have an ICP of from around 5 to

15 mm Hg. This can vary depending upon posture. For example, if a patient who is

supine suddenly stands up, his ICP will fall, and if he is dehydrated or taking

antihypertensives that antagonize alpha-1 vasoconstriction, he can become dizzy

or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only for

a few seconds.

With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3 pulse

pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg, then

MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

CPP of 53 is close to the limit for survival.

And this is in a patient without a head injury. Given a patient with rising

intracranial pressure, it becomes obvious that a higher MAP is needed to

adequately perfuse the brain.

These concepts are taught in the traumatic brain injury courses, but not

emphasized, I fear, in paramedic training.

So my question is this: How many of you who are EMS educators use this in your

teaching? How many of you who are Paramedics have had this training and

understand these concepts?

Are we doing enough to educate our medics to the basics of brain perfusion with

the current guidelines about fluid resuscitation?

Gene Gandy, JD, LP, NREMTP

PERCOMONLINE.COM

Tucson, AZ

..

[Guest guest]

To expand upon Don's perspicacious thoughts, the concept is based upon the

Monro-Kellie doctrine, first expounded by Monro, a ish surgeon

who lived from 1733-1817, and Kellie, an 18th century ish anatomist.

The doctrine says that in the brain, which sits in a closed container, the sum

of the volumes of brain, CSF, and intracranial blood is constant; an increase in

one should cause a decrease in one or both of the remaining. A Google search on

any of a number of subjects involving conditions involving the brain and cranium

will turn up a slew of articles explaining this and the role of MAP and CPP in

maintaining adequate cerebral perfusion.

I think that when Pepe and Mattox (I think it was them) came up with the

permissive hypotension doctrine, as often happens, people rushed to judgment

about what it meant and more or less ignored what it did not mean. For isolated

penetrating thoracic trauma it makes sense. For brain trauma, it does not.

GG

Question regarding fluid resuscitation

>

> For the last few years, fluid resuscitation of trauma patients has been aimed

at

> maintaining a systolic BP of 80-90 mm Hg. The concept is that of " permissive

> hypotension " based upon hydrostatic concerns about the effects of heightened

> hydrostatic pressures in the fact of internal bleeding. It has been postulated

> that increased hydrostatic pressures will dislodge clots that have been formed

> as a natural response to injury, and that increased fluid volumes will dilute

> clotting factors and lead to increased bleeding. These concepts are valid.

>

> However, I propose that this concept fails to take into consideration one

vital

> aspect of trauma care, that of adequate perfusion of the brain. Cerebral

> perfusion pressure (CPP) is the measure of brain perfusion, and it must be

> maintained at a level of 80 mm Hg or better. Studies show that when a

patient's

> CPP is maintained at that level, there is a 35% improvement in outcomes,

whereas

> lower CPPs result in poorer outcomes.

>

> There are two components of blood pressure: the systolic and diastolic

readings.

> Systolic pressure represents hydrostatic pressure, and diastolic pressure

> represents the degree of vasoconstriction. This is an oversimplification, but

it

> is

>

> basically accurate. Simply maintaining a systolic pressure of 80-90 mm Hg does

> not insure adequate CPP.

>

> In order to figure CPP, one must first determine mean arterial pressure (MAP)

> and estimate the intracranial pressure (ICP). Intracranial pressure cannot be

> monitored in the field, but can be estimated based upon clinical observations.

>

> The formula for CPP is this: CPP = MAP - ICP.

>

> MAP can easily be computed by this formula: (1/3 pulse pressure) + diastolic

> pressure. Thus, a patient with a BP of 140/80 will have a pulse pressure of

60.

> One-third of 60 is 20, and added to the diastolic pressure of 80, results in a

> MAP of 100.

>

> Normal patients without head injuries, at rest, have an ICP of from around 5

to

> 15 mm Hg. This can vary depending upon posture. For example, if a patient who

is

> supine suddenly stands up, his ICP will fall, and if he is dehydrated or

taking

> antihypertensives that antagonize alpha-1 vasoconstriction, he can become

dizzy

> or even faint. Conversely, when one coughs or sneezes, ICP spikes, but only

for

> a few seconds.

>

> With a MAP of 100, and an estimated ICP of 15, the CPP would be 85, which is

> fine. But if the BP is, for example, 90/50, then the MAP is only 63. [1/3

pulse

> pressure (40) = 13. Diastolic pressure of 50 + 13 = 63, the MAP.

>

> Using the formula CPP = MAP - ICP, if one assumes a normal ICP of 10 mm Hg,

then

> MAP (63) - estimated ICP (10) = 53, far below the target CPP of 80. In fact, a

> CPP of 53 is close to the limit for survival.

>

> And this is in a patient without a head injury. Given a patient with rising

> intracranial pressure, it becomes obvious that a higher MAP is needed to

> adequately perfuse the brain.

>

> These concepts are taught in the traumatic brain injury courses, but not

> emphasized, I fear, in paramedic training.

>

> So my question is this: How many of you who are EMS educators use this in your

> teaching? How many of you who are Paramedics have had this training and

> understand these concepts?

>

> Are we doing enough to educate our medics to the basics of brain perfusion

with

> the current guidelines about fluid resuscitation?

>

> Gene Gandy, JD, LP, NREMTP

> PERCOMONLINE.COM

> Tucson, AZ

>

> .

>

>

[Guest guest]

from a field perspective, giving fluids to temporarily maintain B/P and CPP

is just that....a temporary effort.

from a clinical perspective, I've seen many folks 'walking, talking and

potty trained' with H/H of 5g/15%- they do tend to decompensate rapidly when

stressed. I think that the still ambulatory patient with the lowest reading

was around 3.9/11%....

any time there is leaking from the vascular system, fluid replacement is

only the first step. The critical step is fixing the leak- In trauma, this is

generally with transfusion followed by surgery (or surgery followed by

transfusion, depending on the situation). For other conditions, other fixes

may apply....for example, relieving a chronic bladder neck obstruction with a

Foley catheter may result in a profound diuresis- possibly over 3

liters/hour- appropriate fluid replacement (baseline plus 3/4ths of the hourly

output x 24 hours, then baseline plus 1/2 hourly output for 24 hours, etc) and

tincture of time will fix this problem.

ck

In a message dated 06/30/11 01:04:45 Central Daylight Time,

txladymedic@... writes:

I've looked to see if there was an article or study on the internet saying

at what hematocrit level does oxygenation cease and can't find one. I

found research saying in general hematocrit levels <23% increase mortality but

still nothing specific to at what point does oxygenation cease.

[Guest guest]

Thanks doc, and Gene, this has been a great topic. Does anyone have any

information on the use of artificial blood, possibly in the field?

Sent from my iPhone

McGee, EMT-P

> from a field perspective, giving fluids to temporarily maintain B/P and CPP

> is just that....a temporary effort.

>

> from a clinical perspective, I've seen many folks 'walking, talking and

> potty trained' with H/H of 5g/15%- they do tend to decompensate rapidly when

> stressed. I think that the still ambulatory patient with the lowest reading

> was around 3.9/11%....

>

> any time there is leaking from the vascular system, fluid replacement is

> only the first step. The critical step is fixing the leak- In trauma, this is

> generally with transfusion followed by surgery (or surgery followed by

> transfusion, depending on the situation). For other conditions, other fixes

> may apply....for example, relieving a chronic bladder neck obstruction with a

> Foley catheter may result in a profound diuresis- possibly over 3

> liters/hour- appropriate fluid replacement (baseline plus 3/4ths of the hourly

> output x 24 hours, then baseline plus 1/2 hourly output for 24 hours, etc) and

> tincture of time will fix this problem.

>

> ck

>

>

> In a message dated 06/30/11 01:04:45 Central Daylight Time,

> txladymedic@... writes:

>

> I've looked to see if there was an article or study on the internet saying

> at what hematocrit level does oxygenation cease and can't find one. I

> found research saying in general hematocrit levels <23% increase mortality but

> still nothing specific to at what point does oxygenation cease.

>

>

[Guest guest]

Me too. It's amazing what the sympathetic nervous system can do. But

ultimately, lack of fluid volume will get you.

Of course we must get the " leaking " patients to a surgeon. That's who can fix

them. We cannot. I cringe when I think about all that has been written about

" stabilizing " a trauma patient in the field, and how that concept went wrong

with Princess Di. The French system was fatally flawed, and probably still is,

because it operates on the premise that a trauma patient who is bleeding

internally can be " stabilized " in the field.

The understanding of this is nothing more than simple plumbing. If there's leak

in the system, your water bill will go up. You can't fix it by wishing. You

have to find the leak and fix it. That's done by the surgeons, not by us.

GG

Re: Re: Question regarding fluid resuscitation

from a field perspective, giving fluids to temporarily maintain B/P and CPP

is just that....a temporary effort.

from a clinical perspective, I've seen many folks 'walking, talking and

potty trained' with H/H of 5g/15%- they do tend to decompensate rapidly when

stressed. I think that the still ambulatory patient with the lowest reading

was around 3.9/11%....

any time there is leaking from the vascular system, fluid replacement is

only the first step. The critical step is fixing the leak- In trauma, this is

generally with transfusion followed by surgery (or surgery followed by

transfusion, depending on the situation). For other conditions, other fixes

may apply....for example, relieving a chronic bladder neck obstruction with a

Foley catheter may result in a profound diuresis- possibly over 3

liters/hour- appropriate fluid replacement (baseline plus 3/4ths of the hourly

output x 24 hours, then baseline plus 1/2 hourly output for 24 hours, etc) and

tincture of time will fix this problem.

ck

In a message dated 06/30/11 01:04:45 Central Daylight Time,

txladymedic@... writes:

I've looked to see if there was an article or study on the internet saying

at what hematocrit level does oxygenation cease and can't find one. I

found research saying in general hematocrit levels <23% increase mortality but

still nothing specific to at what point does oxygenation cease.

[Guest guest]

Me too. It's amazing what the sympathetic nervous system can do. But

ultimately, lack of fluid volume will get you.

Of course we must get the " leaking " patients to a surgeon. That's who can fix

them. We cannot. I cringe when I think about all that has been written about

" stabilizing " a trauma patient in the field, and how that concept went wrong

with Princess Di. The French system was fatally flawed, and probably still is,

because it operates on the premise that a trauma patient who is bleeding

internally can be " stabilized " in the field.

The understanding of this is nothing more than simple plumbing. If there's leak

in the system, your water bill will go up. You can't fix it by wishing. You

have to find the leak and fix it. That's done by the surgeons, not by us.

GG

Re: Re: Question regarding fluid resuscitation

from a field perspective, giving fluids to temporarily maintain B/P and CPP

is just that....a temporary effort.

from a clinical perspective, I've seen many folks 'walking, talking and

potty trained' with H/H of 5g/15%- they do tend to decompensate rapidly when

stressed. I think that the still ambulatory patient with the lowest reading

was around 3.9/11%....

any time there is leaking from the vascular system, fluid replacement is

only the first step. The critical step is fixing the leak- In trauma, this is

generally with transfusion followed by surgery (or surgery followed by

transfusion, depending on the situation). For other conditions, other fixes

may apply....for example, relieving a chronic bladder neck obstruction with a

Foley catheter may result in a profound diuresis- possibly over 3

liters/hour- appropriate fluid replacement (baseline plus 3/4ths of the hourly

output x 24 hours, then baseline plus 1/2 hourly output for 24 hours, etc) and

tincture of time will fix this problem.

ck

In a message dated 06/30/11 01:04:45 Central Daylight Time,

txladymedic@... writes:

I've looked to see if there was an article or study on the internet saying

at what hematocrit level does oxygenation cease and can't find one. I

found research saying in general hematocrit levels <23% increase mortality but

still nothing specific to at what point does oxygenation cease.