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The Science Behind Trauma Care Dr. Bryan E. Bledsoe Professor, Emergency Medicine The George Washington University Medical Center
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Page 1: The Science Behind Trauma Care

The Science Behind Trauma Care

The Science Behind Trauma Care

Dr. Bryan E. BledsoeProfessor, Emergency Medicine

The George Washington University Medical Center

Dr. Bryan E. BledsoeProfessor, Emergency Medicine

The George Washington University Medical Center

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Audience InteractionAudience Interaction

Which of the following actresses is my favorite?

A. Sandra Bullock

B. Angelina Jolie

C. Salma Hayek

D. Nicole Kidman

E. George Michael

Which of the following actresses is my favorite?

A. Sandra Bullock

B. Angelina Jolie

C. Salma Hayek

D. Nicole Kidman

E. George Michael

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Science in Trauma CareScience in Trauma Care

Negative Evidence

No Evidence

Or

Equivocal Evidence

Positive Evidence

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Levels of EvidenceLevels of Evidence

Not all scientific evidence is the same.Not all scientific evidence is the same.

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Audience InteractionAudience Interaction

My ambulance service practices evidence-based prehospital care?

A. Strongly agree

B. Agree

C. Neither agree nor disagree

D. Disagree

E. Strongly disagree.

My ambulance service practices evidence-based prehospital care?

A. Strongly agree

B. Agree

C. Neither agree nor disagree

D. Disagree

E. Strongly disagree.

Page 10: The Science Behind Trauma Care

Levels of EvidenceLevels of Evidence

Center for Evidence-Based Medicine (Oxford)

Ia. Meta-analysis of RCTsIb. One RCT.IIa. Controlled trial without randomisation.IIb. One other type of quasi-experimental study.III. Descriptive studies, such as comparative studies, correlation studies, and case-control studies.IV. Expert committee reports or opinions, or clinical experience of respected authorities or both.

Center for Evidence-Based Medicine (Oxford)

Ia. Meta-analysis of RCTsIb. One RCT.IIa. Controlled trial without randomisation.IIb. One other type of quasi-experimental study.III. Descriptive studies, such as comparative studies, correlation studies, and case-control studies.IV. Expert committee reports or opinions, or clinical experience of respected authorities or both.

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Levels of EvidenceLevels of Evidence

American Heart Association1. Positive randomized controlled trials.

2. Neutral randomized controlled trials.

3. Prospective, non-randomized controlled trials.

4. Retrospective, non-randomized controlled trials

5. Case series (no control group)

6. Animal studies

7. Extrapolations

8. Rational conjecture (common sense)

American Heart Association1. Positive randomized controlled trials.

2. Neutral randomized controlled trials.

3. Prospective, non-randomized controlled trials.

4. Retrospective, non-randomized controlled trials

5. Case series (no control group)

6. Animal studies

7. Extrapolations

8. Rational conjecture (common sense)

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Levels of EvidenceLevels of Evidence

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Levels of EvidenceLevels of Evidence

The closer a study adheres to the scientific method, the more valid the study.

The more valid the study, the closer it is to the truth.

The closer a study adheres to the scientific method, the more valid the study.

The more valid the study, the closer it is to the truth.

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Ranking the EvidenceRanking the Evidence

Class I:Derived from the strongest studies of therapeutic interventions (RCTs) in humans.

Used to support treatment recommendations of the highest order called practice standardspractice standards.

Class I:Derived from the strongest studies of therapeutic interventions (RCTs) in humans.

Used to support treatment recommendations of the highest order called practice standardspractice standards.

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Ranking the EvidenceRanking the Evidence

Class II:Derived from the comparative studies with less strength (nonrandomized cohort studies, RCTs with significant design flaws, and case-control studies).

Used to support recommendations called guidelinesguidelines.

Class II:Derived from the comparative studies with less strength (nonrandomized cohort studies, RCTs with significant design flaws, and case-control studies).

Used to support recommendations called guidelinesguidelines.

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Ranking the EvidenceRanking the Evidence

Class III:Derived from the other sources of information, including case series and expert opinion.

Used to support practice optionspractice options.

Class III:Derived from the other sources of information, including case series and expert opinion.

Used to support practice optionspractice options.

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Ranking the EvidenceRanking the Evidence

Overall term for all of the recommendations is practice parameters.practice parameters.

Overall term for all of the recommendations is practice parameters.practice parameters.

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EMS Practice ChangesEMS Practice Changes

EMS Practices refuted by empiric evidence:

Critical Incident Stress Management (CISM)

MAST/PASG

Trendelenburg Position

High-Volume Fluid Resuscitation

EMS Practices refuted by empiric evidence:

Critical Incident Stress Management (CISM)

MAST/PASG

Trendelenburg Position

High-Volume Fluid Resuscitation

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EMS Practice ChangesEMS Practice Changes

EMS Practices unsupported by empiric evidence:

Medical Priority DispatchSystem Status ManagementHigh-Dose EpinephrineHigh-Dose Steroids for Acute Spinal Cord InjuryIntraosseous NeedlesCPR Compression Vest

EMS Practices unsupported by empiric evidence:

Medical Priority DispatchSystem Status ManagementHigh-Dose EpinephrineHigh-Dose Steroids for Acute Spinal Cord InjuryIntraosseous NeedlesCPR Compression Vest

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EMS Practice ChangesEMS Practice Changes

EMS Practice changes based upon empiric evidence:

AED usage (first 6-8 minutes)

CPR

Field death pronouncement in blunt traumatic cardiac arrest.

EMS Practice changes based upon empiric evidence:

AED usage (first 6-8 minutes)

CPR

Field death pronouncement in blunt traumatic cardiac arrest.

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EMS Practice ChangesEMS Practice Changes

EMS Practices at risk for change because of empiric evidence:

Pediatric Endotracheal Intubation

Rapid Sequence Intubation (RSI) in Traumatic Brain Injury (TBI)

Endotracheal Intubation in TBI

EMS Practices at risk for change because of empiric evidence:

Pediatric Endotracheal Intubation

Rapid Sequence Intubation (RSI) in Traumatic Brain Injury (TBI)

Endotracheal Intubation in TBI

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Guiding Prehospital CareGuiding Prehospital Care

1. There should be a link between the available evidence and treatment recommendations.

2. Empirical evidence should take precedence over expert judgement in the development of guidelines.

1. There should be a link between the available evidence and treatment recommendations.

2. Empirical evidence should take precedence over expert judgement in the development of guidelines.

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Guiding Prehospital CareGuiding Prehospital Care

“In science, there are no authorities.”

Carl Sagan, PhD

1934-1996

“In science, there are no authorities.”

Carl Sagan, PhD

1934-1996

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Guiding Prehospital CareGuiding Prehospital Care

3. The available research should be searched using appropriate and comprehensive search terminology.

4. A thorough review of the scientific literature should precede guideline development.

3. The available research should be searched using appropriate and comprehensive search terminology.

4. A thorough review of the scientific literature should precede guideline development.

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Guiding Prehospital CareGuiding Prehospital Care

5. The evidence should be evaluated and weighted, depending upon the scientific validity of the method used to generate the evidence.

6. The strength of the evidence should be reflected in the strength of the recommendations reflecting scientific certainty (or the lack thereof).

5. The evidence should be evaluated and weighted, depending upon the scientific validity of the method used to generate the evidence.

6. The strength of the evidence should be reflected in the strength of the recommendations reflecting scientific certainty (or the lack thereof).

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Guiding Prehospital CareGuiding Prehospital Care

7. Expert judgement should be used to evaluate the quality of the literature and to formulate guidelines when the evidence is weak or nonexistent.

8. Guideline development should be a multidisciplinary process, involving key groups affected by the recommendations.

7. Expert judgement should be used to evaluate the quality of the literature and to formulate guidelines when the evidence is weak or nonexistent.

8. Guideline development should be a multidisciplinary process, involving key groups affected by the recommendations.

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Audience InteractionAudience Interaction

In regard to the OPALS study:A. I follow the OPALS study regularly.

B. I have read some of the OPALS study papers.

C. I have heard of the OPALS study but not seen any results.

D. What is the OPALS study?

E. None of the above applies.

In regard to the OPALS study:A. I follow the OPALS study regularly.

B. I have read some of the OPALS study papers.

C. I have heard of the OPALS study but not seen any results.

D. What is the OPALS study?

E. None of the above applies.

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Empiric Research in EMSEmpiric Research in EMS

Phase I: Determined baseline survival rate for each study community (36 months) prior to Phase II.

Phase II: Assessed the survival for 12 months after the introduction of rapid defibrillation and demonstrated that relatively inexpensive community rapid defibrillation programs increase survival for cardiac arrest patients (n=5,000+ patients).

Phase III: Assessed survival outcomes months after the introduction of full ALS programs for 36 months for cardiac arrest patients and major trauma patients, and for 6 months for respiratory distress patients.

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Empiric Research in EMSEmpiric Research in EMS

Phase I: Survival improved with:• Decreasing EMS response intervals • Bystander-CPR • First responder CPR by fire or police Phase II: Survival improved with:• Rapid defibrillation (survival increased from 3.9% to

5.2%) resulted in 33% improvement in survival• An additional 21 lives saved each year• Increased survival was also associated with bystander

and first responder CPR.

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Empiric Research in EMSEmpiric Research in EMS

Phase III: Cardiac Arrest:

• The addition of advanced-life-support interventions did not improve the rate of survival after out-of-hospital cardiac arrest in a previously optimized emergency-medical-services system of rapid defibrillation.

• 8-minute response time too long.

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Empiric Research in EMSEmpiric Research in EMS

Phase III: Cardiac Arrest:

• Most cardiac arrests occur in private locations (84.7%) compared to public places (15.3%). Communities should review locations of their cardiac arrests when designing CPR training and public access defibrillation programs.

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Empiric Research in EMSEmpiric Research in EMS

Phase III: Cardiac Arrest:• Among ALS interventions, intubation, atropine and

epinephrine had a negative association and only lidocaine had a positive association with survival.

• Pediatric cardiac arrests are most often due to respiratory arrests or trauma, SIDS, trauma and drowning.

• Citizen-initiated CPR is strongly and independently associated with better quality of life.

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Empiric Research in EMSEmpiric Research in EMS

Phase III: Chest Pain:• Clearly showed important benefit from ALS programs

for mortality and other outcomes.

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Empiric Research in EMSEmpiric Research in EMS

Phase III: Respiratory Distress:• After adjustment for demographic, clinical, and EMS

factors, the only interventions associated with better survival were salbutamol and NTG.

• Most children are not severely ill, most do not receive ALS interventions, there is a high rate of non-transport, and the vast majority are discharged home from the ED.

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Empiric Research in EMSEmpiric Research in EMS

Phase III: Pediatric Care:• The majority of patients did not require immediate or

urgent medical care and had good short-term outcomes.

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Science in Trauma CareScience in Trauma Care

Practices with strong positive evidence:Access to trauma centers

Specialized care (pediatrics, burns, spinal cord injury)

Practices with strong positive evidence:Access to trauma centers

Specialized care (pediatrics, burns, spinal cord injury)

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Science in Trauma CareScience in Trauma Care

Practices with positive evidence:Permissive hypotension

Splinting

Pain management

Head injury management

Hemoglobin-Based Oxygen Carrying Solutions (HBOCs)

Practices with positive evidence:Permissive hypotension

Splinting

Pain management

Head injury management

Hemoglobin-Based Oxygen Carrying Solutions (HBOCs)

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Science in Trauma CareScience in Trauma Care

Practices with no evidence or equivocal evidence:

The “Golden Hour”

Medical helicopters

Trendelenburg position

Traction splints

Rapid sequence intubation (RSI) in traumatic brain injury (TBI)

Practices with no evidence or equivocal evidence:

The “Golden Hour”

Medical helicopters

Trendelenburg position

Traction splints

Rapid sequence intubation (RSI) in traumatic brain injury (TBI)

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Science in Trauma CareScience in Trauma Care

Practices with negative evidence:MAST/PASG

Steroids for acute SCI

High-volume fluid therapy

Prehospital intubation in traumatic brain injury

Pediatric endotracheal intubation

Practices with negative evidence:MAST/PASG

Steroids for acute SCI

High-volume fluid therapy

Prehospital intubation in traumatic brain injury

Pediatric endotracheal intubation

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Audience ParticipationAudience Participation

In regard to current prehospital practice in my system, which of the following best describes trauma care?

A. We still used MAST/PASG and administer large volumes of fluid to restore normal BP.B. We do not use the MAST/PASG but administer

large volumes of fluid to restore BP.C. We administer enough fluid to maintain a blood

pressure >100 mm Hg.D. We administer enough fluid to maintain a blood

pressure > 90 mm Hg.E. We administer enough fluid to maintain a blood

pressure > 80 mm Hg.

In regard to current prehospital practice in my system, which of the following best describes trauma care?

A. We still used MAST/PASG and administer large volumes of fluid to restore normal BP.B. We do not use the MAST/PASG but administer

large volumes of fluid to restore BP.C. We administer enough fluid to maintain a blood

pressure >100 mm Hg.D. We administer enough fluid to maintain a blood

pressure > 90 mm Hg.E. We administer enough fluid to maintain a blood

pressure > 80 mm Hg.

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Science in Trauma CareScience in Trauma Care

Practices with strong negative evidence:Scene stabilization

Practices with strong negative evidence:Scene stabilization

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Changes in US Trauma PracticeChanges in US Trauma Practice

IV Fluid Restriction

Permissive Hypotension

Hemoglobin-Based Oxygen Carrying Solutions (HBOCs)

Less Aggressive Airway Management

Helicopter Overutilization

IV Fluid Restriction

Permissive Hypotension

Hemoglobin-Based Oxygen Carrying Solutions (HBOCs)

Less Aggressive Airway Management

Helicopter Overutilization

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IV Fluid RestrictionIV Fluid Restriction

Should prehospital personnel administer large volumes of IV fluids rapidly to trauma victims or delay fluid resuscitation until hospital arrival?

Should prehospital personnel administer large volumes of IV fluids rapidly to trauma victims or delay fluid resuscitation until hospital arrival?

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IV Fluid RestrictionIV Fluid Restriction

Traditional approach to trauma patient with hypotension was 2 large bore IVs and wide open crystalloid administration.

Traditional approach to trauma patient with hypotension was 2 large bore IVs and wide open crystalloid administration.

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IV Fluid RestrictionIV Fluid Restriction

Recommendation has been to replace lost blood with isotonic crystalloids at a 3:1 ratio (IVF:blood loss)

Recommendation has been to replace lost blood with isotonic crystalloids at a 3:1 ratio (IVF:blood loss)

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IV Fluid RestrictionIV Fluid Restriction

High volume IV fluid administration was based on several animal studies from the 1950s and 1960s.

High volume IV fluid administration was based on several animal studies from the 1950s and 1960s.

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IV Fluid RestrictionIV Fluid Restriction

High volume IV fluid treatment was used in Viet Nam and transferred to US and western civilian prehospital care practices.

High volume IV fluid treatment was used in Viet Nam and transferred to US and western civilian prehospital care practices.

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IV Fluid RestrictionIV Fluid Restriction

Several animal studies in the 1980s and 1990s found that treatment with IV fluids before hemorrhage was controlled increased the mortality rate, especially if the BP was elevated.

Several animal studies in the 1980s and 1990s found that treatment with IV fluids before hemorrhage was controlled increased the mortality rate, especially if the BP was elevated.

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IV Fluid RestrictionIV Fluid Restriction

Raising the BP and restoring perfusion to vital organs are clearly believed to be beneficial after hemorrhage is controlled.

Growing evidence indicates that raising it before achieving adequate hemostasis may be detrimental.

Raising the BP and restoring perfusion to vital organs are clearly believed to be beneficial after hemorrhage is controlled.

Growing evidence indicates that raising it before achieving adequate hemostasis may be detrimental.

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IV Fluid RestrictionIV Fluid Restriction

Administering large quantities of IV fluids without controlling the hemorrhage results in:

hemodilution with decreased hematocritdecreased available hemoglobin (and oxygen-

carrying capacity)decreased clotting factors.

This effect is found regardless of the fluid used (blood, LR, NS, hypertonic saline).

Administering large quantities of IV fluids without controlling the hemorrhage results in:

hemodilution with decreased hematocritdecreased available hemoglobin (and oxygen-

carrying capacity)decreased clotting factors.

This effect is found regardless of the fluid used (blood, LR, NS, hypertonic saline).

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IV Fluid RestrictionIV Fluid Restriction

Bickell WH, Wall MJ Jr, Pepe PE, et al. Immediate versus delayed fluid resuscitation for hypotensive patients with penetrating torso injuries. N Eng J Med. 1994;331:1105-9

598 patients with penetrating torso injury and systolic BP ≤ 90 mmHg in prehospital setting.

Randomized to receive standard high-volume fluids or fluids delayed until patient in OR.

Bickell WH, Wall MJ Jr, Pepe PE, et al. Immediate versus delayed fluid resuscitation for hypotensive patients with penetrating torso injuries. N Eng J Med. 1994;331:1105-9

598 patients with penetrating torso injury and systolic BP ≤ 90 mmHg in prehospital setting.

Randomized to receive standard high-volume fluids or fluids delayed until patient in OR.

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IV Fluid RestrictionIV Fluid Restriction

Results:Group Divisions

Delayed: n=289Standard fluids: n=309

Survival:Delayed: 70%Standard fluids: 62%

Complications:Delayed: 23%Standard fluids: 30%

Results:Group Divisions

Delayed: n=289Standard fluids: n=309

Survival:Delayed: 70%Standard fluids: 62%

Complications:Delayed: 23%Standard fluids: 30%

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IV Fluid RestrictionIV Fluid Restriction

CONCLUSIONS: For hypotensive patients with penetrating torso injuries, delay of aggressive fluid resuscitation until operative intervention improves the outcome.

CONCLUSIONS: For hypotensive patients with penetrating torso injuries, delay of aggressive fluid resuscitation until operative intervention improves the outcome.

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IV Fluid RestrictionIV Fluid Restriction

Tentative Hypothesis:

At this time, intravenous fluid resuscitation should probably be delayed until hemostasis is obtained.

Tentative Hypothesis:

At this time, intravenous fluid resuscitation should probably be delayed until hemostasis is obtained.

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IV Fluid RestrictionIV Fluid Restriction

Literature has primarily looked at penetrating trauma.

The role of fluid resuscitation in patients with blunt trauma is less clear.

Further studies are needed.

Literature has primarily looked at penetrating trauma.

The role of fluid resuscitation in patients with blunt trauma is less clear.

Further studies are needed.

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IV Fluid RestrictionIV Fluid Restriction

Current recommendation for blunt trauma is to administer just enough fluid to maintain perfusion.

Rapid, high-volume fluid administration is discouraged.

Current recommendation for blunt trauma is to administer just enough fluid to maintain perfusion.

Rapid, high-volume fluid administration is discouraged.

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IV Fluid RestrictionIV Fluid Restriction

Fluid resuscitation may be of value in patients who are moribund with systolic pressures <40 mmHg.

Fluid resuscitation may be of value in patients who are moribund with systolic pressures <40 mmHg.

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IV Fluid RestrictionIV Fluid Restriction

Patients with hypotension due to severe hemorrhage from isolated extremity injuries may do better with aggressive prehospital IV fluid resuscitation after hemostasis.

Patients with hypotension due to severe hemorrhage from isolated extremity injuries may do better with aggressive prehospital IV fluid resuscitation after hemostasis.

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IV Fluid RestrictionIV Fluid Restriction

Complications of preoperative fluid resuscitation:

Secondary bleeding or acceleration of ongoing hemorrhageAdult respiratory distress syndrome (Danang Lung)SepsisCoagulopathiesRenal failure

Complications of preoperative fluid resuscitation:

Secondary bleeding or acceleration of ongoing hemorrhageAdult respiratory distress syndrome (Danang Lung)SepsisCoagulopathiesRenal failure

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IV Fluid RestrictionIV Fluid Restriction

Conclusions:More research is needed.Data on penetrating trauma is compelling.Fluid resuscitation probably indicated for moribund

patients.Best management strategies for blunt trauma and head

injuries is to administer just enough fluid to maintain perfusion.Rapid transport probably remains the best treatment for

most trauma cases.

Conclusions:More research is needed.Data on penetrating trauma is compelling.Fluid resuscitation probably indicated for moribund

patients.Best management strategies for blunt trauma and head

injuries is to administer just enough fluid to maintain perfusion.Rapid transport probably remains the best treatment for

most trauma cases.

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IV Fluid RestrictionIV Fluid Restriction

Limitations:Most studies on urban trauma patients with short transport times.

Findings may not be applicable to rural trauma patients.

Limitations:Most studies on urban trauma patients with short transport times.

Findings may not be applicable to rural trauma patients.

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Permissive HypotensionPermissive Hypotension

Should prehospital personnel attempt to restore blood pressure in trauma patients to pre-trauma levels or practice permissive hypotension?

Should prehospital personnel attempt to restore blood pressure in trauma patients to pre-trauma levels or practice permissive hypotension?

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Permissive HypotensionPermissive Hypotension

Animal studies in the 1980s and 1990s indicated that treatment with IV fluids before hemorrhage was controlled increased the mortality rate, especially if the blood pressure is elevated.

Animal studies in the 1980s and 1990s indicated that treatment with IV fluids before hemorrhage was controlled increased the mortality rate, especially if the blood pressure is elevated.

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Permissive HypotensionPermissive Hypotension

Human research seems to support this premise.

Primarily the Bickell, Wall, Pepe, et al. study previously detailed.

Human research seems to support this premise.

Primarily the Bickell, Wall, Pepe, et al. study previously detailed.

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Permissive HypotensionPermissive Hypotension

There is a natural physiologic compensation when blood pressure is maintained between 70-85 mmHg.

Urine output and cerebral perfusion usually maintained when the BP is within this range.

There is a natural physiologic compensation when blood pressure is maintained between 70-85 mmHg.

Urine output and cerebral perfusion usually maintained when the BP is within this range.

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Permissive HypotensionPermissive Hypotension

Elevation of BP to pre-injury levels, without hemostasis, has been associated with:

Progressive and repeated re-bleedingDecrease in platelets and clotting factors.Dislodgement of a clot at the site of injury.

Elevation of BP to pre-injury levels, without hemostasis, has been associated with:

Progressive and repeated re-bleedingDecrease in platelets and clotting factors.Dislodgement of a clot at the site of injury.

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Permissive HypotensionPermissive Hypotension

Interestingly, the standard treatment for ruptured AAAs has been to keep patients hypotensive until proximal control of the aorta (above the leakage) is attained.This preserves intravascular blood volume and prevents new additional blood loss from the rupture.

Interestingly, the standard treatment for ruptured AAAs has been to keep patients hypotensive until proximal control of the aorta (above the leakage) is attained.This preserves intravascular blood volume and prevents new additional blood loss from the rupture.

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Permissive HypotensionPermissive Hypotension

Large animal studies of uncontrolled hemorrhage indicate that the clot is “popped” at about 80 mmHg systolic pressure. This level has been reproducible in human subjects.

Large animal studies of uncontrolled hemorrhage indicate that the clot is “popped” at about 80 mmHg systolic pressure. This level has been reproducible in human subjects.

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Permissive HypotensionPermissive Hypotension

Many hypothesize that one should not raise blood pressure to more than ¾ of pre-injury levels (~80 mmHg).

Many hypothesize that one should not raise blood pressure to more than ¾ of pre-injury levels (~80 mmHg).

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Permissive HypotensionPermissive Hypotension

Dutton RP, MacKenzie CF, Scalea TM, et al. Hypotensive resuscitation during active hemorrhage: Impact on in-hospital mortality. J Trauma. 2003;52(6):1141-1146

110 patients with hemorrhagic shock were randomized into two groups: BP maintenance > 100 (n=55) or BP maintenance of 70 (n=55). Conclusion: Titration of initial fluid therapy to a lower than normal SBP during active hemorrhage did not affect mortality in this study. Reasons for the decreased overall mortality and the lack of differentiation between groups likely include improvements in diagnostic and therapeutic technology, the heterogeneous nature of human traumatic injuries, and the imprecision of SBP as a marker for tissue oxygen delivery.

Dutton RP, MacKenzie CF, Scalea TM, et al. Hypotensive resuscitation during active hemorrhage: Impact on in-hospital mortality. J Trauma. 2003;52(6):1141-1146

110 patients with hemorrhagic shock were randomized into two groups: BP maintenance > 100 (n=55) or BP maintenance of 70 (n=55). Conclusion: Titration of initial fluid therapy to a lower than normal SBP during active hemorrhage did not affect mortality in this study. Reasons for the decreased overall mortality and the lack of differentiation between groups likely include improvements in diagnostic and therapeutic technology, the heterogeneous nature of human traumatic injuries, and the imprecision of SBP as a marker for tissue oxygen delivery.

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Permissive HypotensionPermissive HypotensionHolmes JF, Sakles JC, Lewis G, Wisner DH. Effects of delaying fluid resuscitation on an injury to the systemic arterial vasculature. Acad Emerg Med. 2002;9(4):267-274

21 sheep underwent thoracotomy and transection of the left internal mammary artery.

Group 1: No fluid resuscitationGroup 2: Resuscitation 15 minutes after injuryGroup 3: Resuscitation 30 minutes after injury

CONCLUSIONS: Rates of hemorrhage from an arterial injury are related to changes in mean arterial pressure. In this animal model, early aggressive fluid resuscitation in penetrating thoracic trauma exacerbates total hemorrhage volume. Despite resumption of hemorrhage from the site of injury, delaying fluid resuscitation results in the best hemodynamic parameters.

Holmes JF, Sakles JC, Lewis G, Wisner DH. Effects of delaying fluid resuscitation on an injury to the systemic arterial vasculature. Acad Emerg Med. 2002;9(4):267-274

21 sheep underwent thoracotomy and transection of the left internal mammary artery.

Group 1: No fluid resuscitationGroup 2: Resuscitation 15 minutes after injuryGroup 3: Resuscitation 30 minutes after injury

CONCLUSIONS: Rates of hemorrhage from an arterial injury are related to changes in mean arterial pressure. In this animal model, early aggressive fluid resuscitation in penetrating thoracic trauma exacerbates total hemorrhage volume. Despite resumption of hemorrhage from the site of injury, delaying fluid resuscitation results in the best hemodynamic parameters.

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Permissive HypotensionPermissive Hypotension

This paradigm shift has significant implications on emergency care:

Trendelenburg position

Use of rapid infusers

Intraosseous infusions

This paradigm shift has significant implications on emergency care:

Trendelenburg position

Use of rapid infusers

Intraosseous infusions

Page 73: The Science Behind Trauma Care

Permissive HypotensionPermissive Hypotension

Fluid restriction and permissive hypotension go hand-in-hand.Fluid resuscitation should be administered in small boluses to maintain peripheral pulse (systolic BP +/- 80 mmHg)

Fluid restriction and permissive hypotension go hand-in-hand.Fluid resuscitation should be administered in small boluses to maintain peripheral pulse (systolic BP +/- 80 mmHg)

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Permissive HypotensionPermissive Hypotension

“During prolonged transport the prehospital care provider must attempt to maintain perfusion to the vital organs. Maintaining the systolic blood pressure in the range of 80-90 mm Hg or the MAP in the range of 60-65 mm Hg, can usually accomplish this with less risk of renewing internal hemorrhage.”

“During prolonged transport the prehospital care provider must attempt to maintain perfusion to the vital organs. Maintaining the systolic blood pressure in the range of 80-90 mm Hg or the MAP in the range of 60-65 mm Hg, can usually accomplish this with less risk of renewing internal hemorrhage.”

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Permissive HypotensionPermissive Hypotension

“Gain IV access en route but give only enough Ringer’s lactate solution or normal saline solution to maintain a blood pressure high enough for adequate peripheral perfusion. Maintaining peripheral perfusion may be defined as producing a peripheral pulse, maintaining level of consciousness, or maintaining blood pressure (90-100 mm Hg systolic).”

“Gain IV access en route but give only enough Ringer’s lactate solution or normal saline solution to maintain a blood pressure high enough for adequate peripheral perfusion. Maintaining peripheral perfusion may be defined as producing a peripheral pulse, maintaining level of consciousness, or maintaining blood pressure (90-100 mm Hg systolic).”

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Permissive HypotensionPermissive Hypotension

What about patients with TBI?What about patients with TBI?

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Traumatic Brain InjuryTraumatic Brain Injury

Oxygenation and Blood PressureHypoxemia (<90% SpO2) and/or hypotension (<90 mm Hg systolic) are associated with poor outcomes.Pulse oximetry and blood pressure must be monitored.Continuous waveform capnography beneficial.

Oxygenation and Blood PressureHypoxemia (<90% SpO2) and/or hypotension (<90 mm Hg systolic) are associated with poor outcomes.Pulse oximetry and blood pressure must be monitored.Continuous waveform capnography beneficial.

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Traumatic Brain InjuryTraumatic Brain Injury

Oxygenation and Blood PressureIn children, hypotension is:

0-1 year: Systolic <65 mm Hg

2-5 years: Systolic < 75 mm Hg

6-12 years: Systolic < 80 mm Hg

13-16 years: Systolic < 90 mm Hg

Oxygenation and Blood PressureIn children, hypotension is:

0-1 year: Systolic <65 mm Hg

2-5 years: Systolic < 75 mm Hg

6-12 years: Systolic < 80 mm Hg

13-16 years: Systolic < 90 mm Hg

Page 79: The Science Behind Trauma Care

Traumatic Brain InjuryTraumatic Brain Injury

Why does TBI require a higher systolic BP than required for permissive hypotension?

CPP = MAP- ICPCPP = MAP- ICP MAP = [DBP+1/3 (SBP-DBP)]

Why does TBI require a higher systolic BP than required for permissive hypotension?

CPP = MAP- ICPCPP = MAP- ICP MAP = [DBP+1/3 (SBP-DBP)]

Page 80: The Science Behind Trauma Care

Traumatic Brain InjuryTraumatic Brain Injury

Slightly higher systolic pressure may be required to maintain CPP in TBI.

Slightly higher systolic pressure may be required to maintain CPP in TBI.

Page 81: The Science Behind Trauma Care

Audience ParticipationAudience Participation

In regard to hemoglobin-based oxygen carrying solutions:

A. I have administered them in the prehospital setting.B. I have seen them administered in the prehospital setting.C. I have read about them but never seen them.D. I have never heard of them.E. None of the above.

In regard to hemoglobin-based oxygen carrying solutions:

A. I have administered them in the prehospital setting.B. I have seen them administered in the prehospital setting.C. I have read about them but never seen them.D. I have never heard of them.E. None of the above.

Page 82: The Science Behind Trauma Care

Oxygen-Carrying IV FluidsOxygen-Carrying IV Fluids

Do oxygen-carrying IV fluids have a future role in prehospital care?

Do oxygen-carrying IV fluids have a future role in prehospital care?

Page 83: The Science Behind Trauma Care

Oxygen-Carrying IV FluidsOxygen-Carrying IV Fluids

Crystalloid solutions have been the primary IV fluid used in prehospital trauma care in the United States.

Crystalloid solutions have been the primary IV fluid used in prehospital trauma care in the United States.

Page 84: The Science Behind Trauma Care

Oxygen-Carrying IV FluidsOxygen-Carrying IV Fluids

In most Commonwealth and in many Latin American countries colloids [polygeline (Haemaccel)] is used.

In most Commonwealth and in many Latin American countries colloids [polygeline (Haemaccel)] is used.

Page 85: The Science Behind Trauma Care

HBOCsHBOCs

Each molecule of hemoglobin can carry 4 molecules of oxygen.

Each molecule of hemoglobin can carry 4 molecules of oxygen.

Page 86: The Science Behind Trauma Care

HBOCsHBOCs

The amount of oxygen on the hemoglobin (oxygen saturation) is dependent upon the partial pressure of oxygen.

The amount of oxygen on the hemoglobin (oxygen saturation) is dependent upon the partial pressure of oxygen.

Page 87: The Science Behind Trauma Care

HBOCsHBOCs

The amount of oxygen that can be transported is also dependent upon the amount of circulating red blood cells and the hemoglobin contained within.

The amount of oxygen that can be transported is also dependent upon the amount of circulating red blood cells and the hemoglobin contained within.

Page 88: The Science Behind Trauma Care

HBOCsHBOCs

Blood loss and crystalloid fluid therapy decreases the percentage of circulating red blood cells and hemoglobin.

Blood loss and crystalloid fluid therapy decreases the percentage of circulating red blood cells and hemoglobin.

Page 89: The Science Behind Trauma Care

Oxygen-Carrying IV FluidsOxygen-Carrying IV Fluids

Perflurocarbon emulsions

Hemoglobin-based oxygen carrying solutions (HBOCs):

PolyHeme®

Hemopure®

Perflurocarbon emulsions

Hemoglobin-based oxygen carrying solutions (HBOCs):

PolyHeme®

Hemopure®

Page 90: The Science Behind Trauma Care

HBOCsHBOCs

Hemopure®

Derived from bovine blood

Approved for use in South Africa

Intensive study underway in the US.

Hemopure®

Derived from bovine blood

Approved for use in South Africa

Intensive study underway in the US.

Page 91: The Science Behind Trauma Care

HBOCsHBOCs

Page 92: The Science Behind Trauma Care

HBOCsHBOCs

Hemopure®

Jul 2002: FDA application filed.Sep 2002: US Army provides $908,900.00 grant to

conduct single-center trial in trauma patients.Nov 2002: Trial expanded to include both in-

hospital and prehospital patients.Feb 2003: Congress awards $4 million to fund

clinical trials. First trials in Dallas with DFR and Parkland.

Hemopure®

Jul 2002: FDA application filed.Sep 2002: US Army provides $908,900.00 grant to

conduct single-center trial in trauma patients.Nov 2002: Trial expanded to include both in-

hospital and prehospital patients.Feb 2003: Congress awards $4 million to fund

clinical trials. First trials in Dallas with DFR and Parkland.

Page 93: The Science Behind Trauma Care

HBOCsHBOCs

Page 94: The Science Behind Trauma Care

HBOCsHBOCs

PolyHeme®

Solution of chemically-modified hemoglobin derived from discarded donated human blood.

Hemoglobin extracted and filtered to remove impurities.

PolyHeme®

Solution of chemically-modified hemoglobin derived from discarded donated human blood.

Hemoglobin extracted and filtered to remove impurities.

Page 95: The Science Behind Trauma Care

HBOCsHBOCs

PolyHeme®

Chemically-modified to create a polymerized form of hemoglobin designed to avoid problems previously experienced with hemoglobin-based blood substitutes:

VasoconstrictionRenal dysfunctionLiver dysfunctionGI distress

Polymerized hemoglobin incorporated into a solution that contains 50 grams of hemoglobin per unit (the same as transfused blood).

PolyHeme®

Chemically-modified to create a polymerized form of hemoglobin designed to avoid problems previously experienced with hemoglobin-based blood substitutes:

VasoconstrictionRenal dysfunctionLiver dysfunctionGI distress

Polymerized hemoglobin incorporated into a solution that contains 50 grams of hemoglobin per unit (the same as transfused blood).

Page 96: The Science Behind Trauma Care

HBOCsHBOCs

Page 97: The Science Behind Trauma Care

HBOCsHBOCs

PolyHeme®

Product must be refrigerated.Shelf-life is 1 year.Clinical prospective randomized controlled trial of

prehospital usage started Sep 2003 in several US cities (1-year, 700-800 patients).Paramedics cannot be blinded for study as

PolyHeme looks like blood.Patients who receive PolyHeme will receive up to 6

more units if needed during the first 12 hours.

PolyHeme®

Product must be refrigerated.Shelf-life is 1 year.Clinical prospective randomized controlled trial of

prehospital usage started Sep 2003 in several US cities (1-year, 700-800 patients).Paramedics cannot be blinded for study as

PolyHeme looks like blood.Patients who receive PolyHeme will receive up to 6

more units if needed during the first 12 hours.

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HBOCsHBOCs

CaliforniaUCSD (San DiegoScripps Mercy (San Diego)

ColoradoDenver H&H (Denver)

DelawareChristiana (Newark)

IllinoisLoyola (Chicago)

IndianaWishard (Indianapolis)Methodist Hospital (Indianapolis)

KentuckyU of K (Lexington)

CaliforniaUCSD (San DiegoScripps Mercy (San Diego)

ColoradoDenver H&H (Denver)

DelawareChristiana (Newark)

IllinoisLoyola (Chicago)

IndianaWishard (Indianapolis)Methodist Hospital (Indianapolis)

KentuckyU of K (Lexington)

MinnesotaMayo (Rochester)

OhioMetro Health (Cleveland)

PennsylvaniaLehigh Valley (Allentown)

TennesseeUT (Memphis)

TexasMemorial-Hermann (Houston)UTHSCSA (San Antonio)

VirginiaSentara (Norfolk)VCU (Richmond)

MinnesotaMayo (Rochester)

OhioMetro Health (Cleveland)

PennsylvaniaLehigh Valley (Allentown)

TennesseeUT (Memphis)

TexasMemorial-Hermann (Houston)UTHSCSA (San Antonio)

VirginiaSentara (Norfolk)VCU (Richmond)

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HBOCsHBOCs

Artificial polymerized hemoglobin can transport oxygen within the plasma.Artificial polymerized hemoglobin can transport oxygen within the plasma.

Page 100: The Science Behind Trauma Care

HBOCsHBOCs

Gould SA, Moore EE, Hoyt DB, et al. The first randomized trial of human polymerized hemoglobin as a blood substitute in acute trauma and emergency surgery. J Am Coll Surg. 1998;187(2):113-2044 trauma patients (33 male, 11 female) were randomized to receive red cells or PolyHeme as their initial fluid replacement after trauma.There were no serious or unexpected outcomes related to PolyHeme.CONCLUSIONS: PolyHeme is safe in acute blood loss, maintains total [Hb] in lieu of red cells despite a marked fall in RBC [Hb], and reduces the use of allogenic blood. PolyHeme appears to be a clinically-useful blood substitute.

Gould SA, Moore EE, Hoyt DB, et al. The first randomized trial of human polymerized hemoglobin as a blood substitute in acute trauma and emergency surgery. J Am Coll Surg. 1998;187(2):113-2044 trauma patients (33 male, 11 female) were randomized to receive red cells or PolyHeme as their initial fluid replacement after trauma.There were no serious or unexpected outcomes related to PolyHeme.CONCLUSIONS: PolyHeme is safe in acute blood loss, maintains total [Hb] in lieu of red cells despite a marked fall in RBC [Hb], and reduces the use of allogenic blood. PolyHeme appears to be a clinically-useful blood substitute.

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HBOCsHBOCs

Gannon CJ, Napolitano LM. Severe anemia after gastrointestinal hemorrhage in a Jehovah’s Witness: new treatment strategies. Critical Care Medicine. 2002;30:1930-1931

50–year-old Jehovah’s Witness had massive UGI bleed from pre-pyloric ulcer (Hb=3.5 grams). Hemorrhage control with injection of epinephrine.

Patient became hemodynamically unstable.

Received 7 units of bovine HBOC and human erythropoietin.

Within 24 hours patient stable and Hb 7.2 grams.

Conclusions: Survival without allogenic blood attained.

Gannon CJ, Napolitano LM. Severe anemia after gastrointestinal hemorrhage in a Jehovah’s Witness: new treatment strategies. Critical Care Medicine. 2002;30:1930-1931

50–year-old Jehovah’s Witness had massive UGI bleed from pre-pyloric ulcer (Hb=3.5 grams). Hemorrhage control with injection of epinephrine.

Patient became hemodynamically unstable.

Received 7 units of bovine HBOC and human erythropoietin.

Within 24 hours patient stable and Hb 7.2 grams.

Conclusions: Survival without allogenic blood attained.

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HBOCsHBOCs

HBOCs look quite promising for prehospital and battlefield emergency care.

Further recommendations await result of first prehospital study.

HBOCs look quite promising for prehospital and battlefield emergency care.

Further recommendations await result of first prehospital study.

Page 103: The Science Behind Trauma Care

Audience ParticipationAudience Participation

In my ambulance service, we use medical helicopters for scene responses:

A. Very Frequently

B. Often

C. Occasionally

D. Rarely

E. Never

In my ambulance service, we use medical helicopters for scene responses:

A. Very Frequently

B. Often

C. Occasionally

D. Rarely

E. Never

Page 104: The Science Behind Trauma Care

HelicoptersHelicopters

Are EMS helicopters effective in decreasing mortality and enhancing trauma care?

Are EMS helicopters effective in decreasing mortality and enhancing trauma care?

Page 105: The Science Behind Trauma Care

HelicoptersHelicopters

Initial studies in the 1980s showed that trauma patients have better outcomes when transported by helicopter.

Today, other than speed, helicopters offer little additional care than provided by ground ambulances.

Initial studies in the 1980s showed that trauma patients have better outcomes when transported by helicopter.

Today, other than speed, helicopters offer little additional care than provided by ground ambulances.

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HelicoptersHelicopters

The number of medical helicopters in the United States has increased from 400 to >700 in the last 4 years.

The number of medical helicopters in the United States has increased from 400 to >700 in the last 4 years.

Page 107: The Science Behind Trauma Care

Helicopters Helicopters

Considerations:Severe injury:

ISS > 15TS < 12RTS ≤ 11Weighted RTS ≥ 4Triss Ps < 0.90

Non-life-threatening injuries:Patients not in above criteriaPatients who refuse ED treatmentPatients discharged from EDPatients not admitted to ICU

Considerations:Severe injury:

ISS > 15TS < 12RTS ≤ 11Weighted RTS ≥ 4Triss Ps < 0.90

Non-life-threatening injuries:Patients not in above criteriaPatients who refuse ED treatmentPatients discharged from EDPatients not admitted to ICU

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HelicoptersHelicopters

Shatney CH, Homan SJ, Sherek JP, et al. The utility of helicopter transport of trauma patients from the injury scene in an urban trauma system. J Trauma. 2002;53(5):817-22

10-year retrospective review of 947 consecutive trauma patients transported to the Santa Clara Valley trauma center.

Blunt trauma: 911Penetrating trauma: 36

Shatney CH, Homan SJ, Sherek JP, et al. The utility of helicopter transport of trauma patients from the injury scene in an urban trauma system. J Trauma. 2002;53(5):817-22

10-year retrospective review of 947 consecutive trauma patients transported to the Santa Clara Valley trauma center.

Blunt trauma: 911Penetrating trauma: 36

Page 109: The Science Behind Trauma Care

HelicoptersHelicopters

Mean ISS = 8.9Deaths in ED = 15Discharged from ED = 312 (33.5%)Hospitalized = 620

ISS ≤ 9 = 339 (54.7%)ISS ≥ 16 = 148 (23.9%)Emergency surgery = 84 (8.9%)

Mean ISS = 8.9Deaths in ED = 15Discharged from ED = 312 (33.5%)Hospitalized = 620

ISS ≤ 9 = 339 (54.7%)ISS ≥ 16 = 148 (23.9%)Emergency surgery = 84 (8.9%)

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HelicoptersHelicopters

Only 17 patients (1.8%) underwent surgery for immediately life-threatening injuries.Helicopter arrival faster = 54.7%Helicopter arrival slower = 45.3%Only 22.4% of the study population were possibly helped by helicopter transport.CONCLUSION: The helicopter is used excessively for scene transport of trauma victims in our metropolitan trauma system. New criteria should be developed for helicopter deployment in the urban trauma environment.

Only 17 patients (1.8%) underwent surgery for immediately life-threatening injuries.Helicopter arrival faster = 54.7%Helicopter arrival slower = 45.3%Only 22.4% of the study population were possibly helped by helicopter transport.CONCLUSION: The helicopter is used excessively for scene transport of trauma victims in our metropolitan trauma system. New criteria should be developed for helicopter deployment in the urban trauma environment.

Page 111: The Science Behind Trauma Care

HelicoptersHelicopters

Eckstein M, Jantos T, Kelly N, et al. Helicopter transport of pediatric trauma patients in an urban emergency medical services system: a critical analysis. J Trauma, 2002;53:340-344.Retrospective review of 189 pediatric trauma patients (<15) transported by helicopter from the scene in LA. Median age: 5 yearsRTS > 7 = 82%ISS < 15 = 83%Admitted to ICU = 18%Discharged from ED = 33%

Eckstein M, Jantos T, Kelly N, et al. Helicopter transport of pediatric trauma patients in an urban emergency medical services system: a critical analysis. J Trauma, 2002;53:340-344.Retrospective review of 189 pediatric trauma patients (<15) transported by helicopter from the scene in LA. Median age: 5 yearsRTS > 7 = 82%ISS < 15 = 83%Admitted to ICU = 18%Discharged from ED = 33%

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HelicoptersHelicopters

CONCLUSION: The majority of pediatric trauma patients transported by helicopter in our study sustained minor injuries. A revised policy to better identify pediatric patients who might benefit from helicopter transport appears to be warranted.

CONCLUSION: The majority of pediatric trauma patients transported by helicopter in our study sustained minor injuries. A revised policy to better identify pediatric patients who might benefit from helicopter transport appears to be warranted.

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HelicoptersHelicopters

Braithwaite CE, Roski M, McDowell R, et al. A critical analysis of on-scene helicopter transport on survival in a statewide trauma system. J Trauma. 1998;45(1):140-4Data for 162,730 Pennsylvania trauma patients obtained from state trauma registry.

Patients treated at 28 accredited trauma centers15,938 patients were transported from the scene by

helicopters.6,273 patients were transported by ALS ground

ambulance.

Braithwaite CE, Roski M, McDowell R, et al. A critical analysis of on-scene helicopter transport on survival in a statewide trauma system. J Trauma. 1998;45(1):140-4Data for 162,730 Pennsylvania trauma patients obtained from state trauma registry.

Patients treated at 28 accredited trauma centers15,938 patients were transported from the scene by

helicopters.6,273 patients were transported by ALS ground

ambulance.

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HelicoptersHelicopters

Patients transported by helicopter:Significantly youngerMalesMore seriously injuredHad lower blood pressure

Helicopter patients:ISS <15 = 55%

Logical regression analysis revealed that when adjusted for other risk factors, transportation by helicopter did not affect the estimated odds of survival.CONCLUSION: A reappraisal of the cost-effectiveness of helicopter triage and transport criteria, when access to ground ALS squads is available, may be warranted.

Patients transported by helicopter:Significantly youngerMalesMore seriously injuredHad lower blood pressure

Helicopter patients:ISS <15 = 55%

Logical regression analysis revealed that when adjusted for other risk factors, transportation by helicopter did not affect the estimated odds of survival.CONCLUSION: A reappraisal of the cost-effectiveness of helicopter triage and transport criteria, when access to ground ALS squads is available, may be warranted.

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HelicoptersHelicopters

Cocanour CS, Fischer RP, Ursie CM. Are scene flights for penetrating trauma justified? J Trauma. 1997;43(1):83-86122 consecutive victims of non-cranial penetrating trauma transported by helicopter from the scene.

Average RTS = 10.6Dead patients = 15.6%

Helicopter did not hasten arrival in for any of the 122 patients.Only 4.9% of patients required patient care interventions beyond those of ground ALS units.CONCLUSION: Scene flights in this metropolitan area for patients who suffered noncranial penetrating injuries demonstrated that these flights were not medically efficacious.

Cocanour CS, Fischer RP, Ursie CM. Are scene flights for penetrating trauma justified? J Trauma. 1997;43(1):83-86122 consecutive victims of non-cranial penetrating trauma transported by helicopter from the scene.

Average RTS = 10.6Dead patients = 15.6%

Helicopter did not hasten arrival in for any of the 122 patients.Only 4.9% of patients required patient care interventions beyond those of ground ALS units.CONCLUSION: Scene flights in this metropolitan area for patients who suffered noncranial penetrating injuries demonstrated that these flights were not medically efficacious.

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HelicoptersHelicopters

Cunningham P, Rutledge R, Baker CC, Clancy TV. A comparison of the association of helicopter and ground ambulance transport with the outcome of injury in trauma patients transported from the scene. J Trauma 1997;43(6):940-946

Data obtained from NC trauma registry from 1987-1993 on trauma patients and compared:

1,346 transported by air17,144 transported by ground

CONCLUSION: The large majority of trauma patients transported by both helicopter and ground ambulance have low severity measures. Outcomes were not uniformly better among patients transported by helicopter. Only a very small subset of patients transported by helicopter appear to have any chance or improved survival.

Cunningham P, Rutledge R, Baker CC, Clancy TV. A comparison of the association of helicopter and ground ambulance transport with the outcome of injury in trauma patients transported from the scene. J Trauma 1997;43(6):940-946

Data obtained from NC trauma registry from 1987-1993 on trauma patients and compared:

1,346 transported by air17,144 transported by ground

CONCLUSION: The large majority of trauma patients transported by both helicopter and ground ambulance have low severity measures. Outcomes were not uniformly better among patients transported by helicopter. Only a very small subset of patients transported by helicopter appear to have any chance or improved survival.

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HelicoptersHelicopters

Moront ML, Gotschall CS, Eichelberger MR. Helicopter transport of injured children: system effectiveness and triage criteria. J Pediatr Surg. 1996;31(8):1183-63,861 children transported by local EMS

1,460 arrived by helicopter2,896 arrived by ground

Helicopter transported patients:ISS <15 = 83%But survival rates for children transported by air were better than

those transported by ground.CONCLUSION: The authors conclude that (1) helicopter transport was associated with better survival rates among injured urban children; (2) pediatric helicopter triage criteria based on GSC and heart rate may improve helicopter utilization without compromising care; (3) current air triage practices result in overuse in approximately 85% of flights.

Moront ML, Gotschall CS, Eichelberger MR. Helicopter transport of injured children: system effectiveness and triage criteria. J Pediatr Surg. 1996;31(8):1183-63,861 children transported by local EMS

1,460 arrived by helicopter2,896 arrived by ground

Helicopter transported patients:ISS <15 = 83%But survival rates for children transported by air were better than

those transported by ground.CONCLUSION: The authors conclude that (1) helicopter transport was associated with better survival rates among injured urban children; (2) pediatric helicopter triage criteria based on GSC and heart rate may improve helicopter utilization without compromising care; (3) current air triage practices result in overuse in approximately 85% of flights.

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HelicoptersHelicopters

Wills VL, Eno L, Walker C, et al. Use of an ambulance-based helicopter retrieval service. Aust N Z J Surg. 2000;70(7):506-510179 trauma patients arrived by helicopter during study year.

122 male57 female

Severity of injuries:ISS < 9 = 67.6%ISS ≥ 16 = 17.9%12 (6.7%) discharged from the ED46 (25.7%) discharged within 48 hours.

Results:17.3% of patients were felt to have benefited from helicopter transport81.0% of patients were felt to have no benefit from helicopter

transport1.7% of patients were felt to have been harmed from helicopter

transport

Wills VL, Eno L, Walker C, et al. Use of an ambulance-based helicopter retrieval service. Aust N Z J Surg. 2000;70(7):506-510179 trauma patients arrived by helicopter during study year.

122 male57 female

Severity of injuries:ISS < 9 = 67.6%ISS ≥ 16 = 17.9%12 (6.7%) discharged from the ED46 (25.7%) discharged within 48 hours.

Results:17.3% of patients were felt to have benefited from helicopter transport81.0% of patients were felt to have no benefit from helicopter

transport1.7% of patients were felt to have been harmed from helicopter

transport

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HelicoptersHelicopters

Bledsoe BE, Wesley AK, Eckstein M, Dunn TM, O’Keefe MF. Helicopter Transport of Trauma Patients: A Meta-Analysis J Trauma (In Press).Meta-Analysis of 22 papers with a cohort of 37,350 patients.ISS ≤ 15 (minor injuries): 60% (99% CI: 54.5-64.8)TS ≥ 13 (minor injuries): 61.4% (99% CI: 60.8-62.0)TRISS Ps > 0.90 (minor injuries): 69.3% (99% CI: 58.5-80.2)Discharged < 24 hours: 24.1% (99% CI: -0.90-52.6)

Bledsoe BE, Wesley AK, Eckstein M, Dunn TM, O’Keefe MF. Helicopter Transport of Trauma Patients: A Meta-Analysis J Trauma (In Press).Meta-Analysis of 22 papers with a cohort of 37,350 patients.ISS ≤ 15 (minor injuries): 60% (99% CI: 54.5-64.8)TS ≥ 13 (minor injuries): 61.4% (99% CI: 60.8-62.0)TRISS Ps > 0.90 (minor injuries): 69.3% (99% CI: 58.5-80.2)Discharged < 24 hours: 24.1% (99% CI: -0.90-52.6)

Page 120: The Science Behind Trauma Care

HelicoptersHelicopters

54

56

58

60

62

64

66

68

70

ISS TS TRISS

Percentagewith minorinjuries

Page 121: The Science Behind Trauma Care

Helicopters (US Accidents)Helicopters (US Accidents)

0

5

10

15

20

25

2004 2002 2000 1998 1996 1994

Accidents

Deaths

Injuries

Page 122: The Science Behind Trauma Care

HelicoptersHelicopters

5

26 27

74

01020304050607080

AllWorkers

Farming Mining AirMedical

Crew

Occupational Deaths per 100,000/year (U.S. 1995-2001)

Source: Johns Hopkins University School of Public Health

Page 123: The Science Behind Trauma Care

HelicoptersHelicopters

An EMS helicopter (HEMS) pilot or crew member flying 20 hours/week for 20 years would have a 40% chance of a fatal crash.Since 2002, more people have been killed in air ambulance crashes than aboard U.S. commercial airlines, though the helicopters travel just a fraction of the distance.

An EMS helicopter (HEMS) pilot or crew member flying 20 hours/week for 20 years would have a 40% chance of a fatal crash.Since 2002, more people have been killed in air ambulance crashes than aboard U.S. commercial airlines, though the helicopters travel just a fraction of the distance.

Page 124: The Science Behind Trauma Care

ConclusionsConclusions

Helicopter transport of trauma patients is over utilized.

Utilization criteria must be studied and revised.

Few trauma patients benefit from helicopter transport.

Helicopter transport of trauma patients is over utilized.

Utilization criteria must be studied and revised.

Few trauma patients benefit from helicopter transport.

Page 125: The Science Behind Trauma Care

ConclusionsConclusions

Data show that helicopters are over utilized for trauma scene responses.Over triage of trauma patients primary factorCosts and risks may not justify benefit for the vast majority of trauma patients.Triage criteria should be based on physiological parameters and not mechanism of injury.

Data show that helicopters are over utilized for trauma scene responses.Over triage of trauma patients primary factorCosts and risks may not justify benefit for the vast majority of trauma patients.Triage criteria should be based on physiological parameters and not mechanism of injury.

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ConclusionsConclusions

More research is needed.Proliferation of helicopter operations reflects economic factors more than patient outcome factors.Data may not be applicable to rural areas.

More research is needed.Proliferation of helicopter operations reflects economic factors more than patient outcome factors.Data may not be applicable to rural areas.

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Audience ParticipationAudience Participation

In my opinion, which country has the best EMS system?

A. United Kingdom

B. United States

C. Australia

D. South Africa

E. France

In my opinion, which country has the best EMS system?

A. United Kingdom

B. United States

C. Australia

D. South Africa

E. France

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Airway ManagementAirway Management

And then, there is airway management. Do you have the rest of the afternoon?

And then, there is airway management. Do you have the rest of the afternoon?

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Audience QuestionsAudience Questions

Questions?

For details on publications, presentations, or biography, see:

http://www.bryanbledsoe.com

Questions?

For details on publications, presentations, or biography, see:

http://www.bryanbledsoe.com