Hemorrhagic Shock

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Hemorrhagic Shock

• Vu Huynh, D.O.
• Emergency Medicine

2
Overview

• Pathophysiology
• Prehospital Care
• Permissive hypotension
• LR v NS
• Crystalloid v Colloid
• Hypertonic Saline
• Blood substitutes

3
Definition of Shock

• Reduced perfusion of vital organs leading to
  inadequate oxygen and nutrients necessary for
  normal tissue and cellular function. (1,5)
• Cellular level
• Reduction of mitochondrial oxygen
• Anaerobic glycolysis of ATP
• Accumulation of pyruvate Lactatic
  Acidosis

4
History

• Shock
• Le Dran, 1731 secousse (jarring)2
• Sparrow shock
• 1920 Blalock showed that shock after trauma was
  due to blood loss 2
• Bluntly traumatize dogs legs
• Increased weight in the legs showed enough blood
  volume loss to account for the shock.

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History

• Hardaway (Ann Surg 1963)
• Porcine Model
• Trauma alone to one thigh produced no mortality.
  
• Hemorrhage alone to 40mm hg systolic for 4hrs
  produced zero mortality.
• Combimed trauma and hemorraghic shock produced
  91 mortality
• Vietnam Wound Analysis (J. Trauma 1978)
• Soldiers often died of shock despite being
  adequate treated with IV fluids and appropriate
  surgical procedures.

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History

• Hardaway (1990 Crit Care)
• Pig Study
• 60 blows to each thigh
• Produced 100 mortality within 48hrs
• Even though normal blood volume was maintained
  with IV fluids.
• Pigs died of DIC and ARDS

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History

• Shock from trauma encompasses both volume loss
  and inflammatory mediators leading to MOF. (2)

8
Epidemiology

• lt 10 of all trauma victims have immediate post
  traumatic hypotension (3)
• 1/3
• Other causes Ptx, tamponade, drug ingestion,
  etc.
• 1/3
• Die of their wounds early
• 1/3
• Amenable to surgical care and fluid resuscitation.

9
Sources of hemorrhage

• Scene
• Chest
• Abdomen
• Retroperitoneal
• Muscle compartments

10
HYPOVOLEMIA

• Baroreceptor reflex (arterial cardiopulmonary)
• Circulating vasoconstrictors
• Chemoreceptor reflexes
• Renal reabsorption of Na and water
• Cerebral ischemia
• Increased SVR and Cardiac Output
• Shunting blood to vital organs

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Decompensation
12
Classes of acute hemorrhage
ATLS 2004. 70kg male
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Prehospital Care

• ATLS or BLS or transport?

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Prehospital Care

• 2006 Turkish Study
• Review of 76 papers pre-hospital ATLS vs BLS
• Variables IV catheter placement, intubation,
  fluid resuscitation, transport time
• Conclusion do not support use of routine ATLS in
  the field
• Demetriades
• 5800 pts brought to hospital by paramedics v.
  bystanders, relatives, or police
• Worse outcome for those brought by paramedics.

16

• Picture of isreali military or war

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Pre-hospital Care

• Scoop and Run (7)
• Immediate evacuation to surgical facility after
  airway and breathing have been secured
• On scene time should not be prolonged by attempts
  to gain an IV line
• gt1hr IV line introduced and fluid therapy started

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• ambulance

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Fluids

• Wiggers 1950s Animal models (7,8,9)
• Blood taken out through a catheter until set
  blood pressure was reached.
• Administration of shed blood did not improved
  morbidity and mortality.

21
Fluids

• Shires 1970s(7,8,9)
• Large extracellular fluid deficit was greater
  than could be attributed to vascular refill alone
• Only infusion of both shed blood and lactated
  ringers to replace the ECF deficit showed
  improved outcome.

22
Fluids

• Third space loss into interstium and tissues
• 31 rule of crystalloid for every 1 ml of blood
  loss
• ATLS 2 liters of crystalloid through large bore
  IV for early treatment of hemorrhagic shock.

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Permissive Hypotension

• Dogma has come under question for uncontrolled
  hemorrhage.
• Shires and similar animal models
• Controlled hemorrhage (8)
• Newer animal and human resuscitation studies
• Uncontrolled hemorrhage
• Permissive hypotension

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Permissive Hypotension

• Bickell (8)
• Porcine model
• Aggressive replacement of blood loss with three
  times the volume of crystalloid
• Increased hemorrhage and decreased survival.
• Stern and Kowalenko (19)
• Pigs bled through femoral catheter and aortotomy
• Resuscitated to systolic blood pressure of 40,
  60, 80mmHg.
• Most bleeding and highest mortality occurred in
  the 80mmHg group.

25
Permissive Hypotension

• Riddez (12)
• Dog aortotomy
• 4 resuscitation groups
• No fluid
• 11 replacement blood loss with LR
• 21
• 31
• Aortic blood flow and blood loss increased with
  the amount of fluid used
• Highest mortality in no fluid and 31 fluid group
• No fluid--gtshock. 31--gtRebleeding

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Permissive Hypotension

• Bickell Mattox (NEJM 1994)
• Randomized prospective trial of 598 patients with
  penetrating torso injuries
• Immediate v delayed resucitation group
• Immediate group average of 900ml LR
• Delayed group 100ml
• Delayed group
• Better survival to discharge rate (70 vs 62
  p0.04)
• Fewer overall complications.

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Permissive Hypotension

• Israeli Defense Forces Guidelines (7)
• CHS
• Normalization of hemodynamic parameters and
  reversal of shock
• UCHS
• Early evacuation to surgical facility considered
  most important step of management after airway
  and breathing have been secured.
• Fluid is only administered when
• Altered sensorium
• Radial pulse cannot be palpated
• Systolic BP lt80mmHg

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Permissive Hypotension

• Australian Institute of trauma and injury
  management 2003 (13)
• Royal college of Surgeons Edinburgh and UK
  Defense Force 2002 Consensus Review (8)
• Kreimeier 1999 Congress Report, Munich.(10)
• Sampalis et al. 1997 J Trauma
• Hambly and Dutton 1996 Resuscitation
• Standard v Rapid infuser

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Permissive Hypotension

• Delaying massive fluid resuscitation until the
  time of surgery prevents
• Exacerbating uncontrolled internal hemorrhage
• Clot dissolution / popping the clot
• Dilution of clotting factors
• Hypothermia

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Permissive Hypotension

• Caveats
• Brain injury
• CPPMAP-ICP
• SBPgt100 mmHg
• Fast evacuation to definitive surgical care
• Unclear results for non-penetrating trauma
• Elderly patients

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Fluids

• Blood
• Crystalloid
• Colloid
• Hypertonic saline

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Blood Disadvantages

• Cost
• Compatability/error18
• Incorrect blood-140,000 (death 12million)
• Immune complications18
• 140,000
• Infection19
• Sepsis 1500,000 (RBCs) 150,000 (platelets)
• Hep B 1250,000
• Hep C HIV 12million
• Storage requirements
• Citrate toxicity
• Hypocalcemia
• Hyperkalemia

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Isotonic crystalloids8

• Advantages
• Cheap
• Easy to store and warm
• Established safety
• Predictable rise in cardiac output
• Disadvantages14
• Large volumes needed
• Dilutional coagulopathy
• Increase cytokine activation7
• No oxygen carrying capacity
• May Increase ICP

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Composition of IV Crystalloid 19
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LR vs NS

• Lowery 1971(Surg Gynecol Obstet)
• Vietnam war study LR v NS
• Healthy soldiers
• No difference in outcome

37
LR vs NS

• Waters 2001 (Aneth Analg)
• Patients undergoing aortic aneurysm repair
• NS
• More volume (500-1000ml)
• Hyperchloremic acidosis
• Dilutional coagulopathy
• Todd (J. Trauma 2007 62636-9)
• Swine bled via liver injury resuscitated to MAP
  90mmHg
• NS
• More volume
• Hyperchloremic acidosis
• Dilutional coagulopathy

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LR vs NS

• Conclusion
• No mortality difference
• LR
• Lower overall volume
• More buffering capacity
• NS
• Metabolic acidosis
• Dilutional coagulopathy
• Preferred fluid outside of US
• Probably no difference for prehospital or early
  fluid resuscitation.

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Colloids16
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Colloids

• Proposed Benefits (15)
• Smaller volume
• Less pulmonary edema
• Stays in the intravascular space
• Quicker return to normal hemodynamics
• Smaller package
• Antioxidant and antinflammatory effects

41
Colloids

• Disadvantages (16)
• Transmission of diseases
• Increased bleeding
• Hypersensitivity reactions
• Renal failure
• Accumulation
• Taken up by RES
• Dose limit (20-50mL/kg)
• Cost

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Colloids

• Schierhout and Robertson BMJ 1998
• 30 total studies, 7 trauma studies
• Albumin, dextran, gelatin v Crystalloid
• Colloids associated with 4 increased risk of
  mortality
• Cochrane meta analysis BMJ 1998
• 63 trials total 4 trauma studies (1977, 1978,
  1983)
• Albumin, 23 trials Hydroxyethyl Starch (HES), 16
  trials Gelitin, 16 trials Dextran, 9 trials
• 6 increased mortality
• Albumin kills our patients (1 out of 17)

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Colloids

• Wilikes (2001 Ann Int Med)
• 27 studies trauma and surgical pts
• Albumin v crystalloid
• No effect of albumin on mortality
• Choi et al.(1999 Crit Care Med)
• All kinds of colloids v crystalloids
• No difference in mortality

45
Colloids

• Cochrane Review 2006
• As colloids are not associated with improvement
  in survival, and as they are more expensive than
  crystalloids, it is hard to see how their
  continued use can be justified outside the
  context of RCTs.

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Colloids

• Problem with meta analysis
• Selection bias of included trials
• Mixing of patients with different diseases
• Use of different kinds of fluids
• Different colloids used
• Mortality used in meta analysis not the end point
  of most original studies

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Colloids

• SAFE trial 2004 (N Engl J Med 2004)
• Double blind RCT, 7000 pts, 16 ICUs, 18 month
  period
• 4 albumin v 0.9 normal saline
• First 4 days volume albumin to saline (11.4)
• No difference in 2 groups in 28 all day cause
  mortality
• Sub group analysis difference between trauma and
  sepsis patients
• RR of death pts with severe sepsis 0.87
• Overall trauma mortality higher for albumin v
  saline (13.5 v 10)
• TBI separated, no difference in mortality
• SAFE brains study proposed

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Colloids

• Conclusion
• Most studies do not show reduction of mortality
• Possible risk of increased mortality
• Increased cost
• Routine use of colloids not supported in Trauma
• May be beneficial in Septic patients, SBP, ARDS
• Promise with HES and newer colloids (16)
• Further RCT trials needed

49
Hypertonic Saline

• Rapid plasma volume expansion (17)
• Pull of fluid to vascular space secondary to
  increased concentration gradient
• Decreases ICP
• Potential benefits in TBI patients
• Military use
• Weighs less
• 1 liter NS bag2744 cm3 in volume and 1.1 kg
• Storage space for helicopters and ground
  ambulances

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Hypertonic Saline

• Adverse effects
• Hyperosmolar coma
• Hypernatremia
• Seizures
• arrhythmias
• Tissue necrosis
• Allergic reactions

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Hypertonic Saline

• First used in 1926 (17)
• Silbert 5 saline to treat burgers disease
• 1.5-3 saline used since 1970s for burns
• Renewed interest 1980
• Brazilian study used 2400 mOsm of hypertonic
  saline for hemorrhagic shock

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Hypertonic Saline

• Hypertonic saline (17)
• 7.5 or 7.2
• Dextran 70 (RescueFlow) or HES (HyperHAES)
• Osmolarity 2500 mOsm/liter
• Na 1200 mmol/liter
• Total volume 250ml

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Hypertonic saline

• Australian prehospital study (JAMA 2004)
• Double blind prospective RCT, 229 pts
• SBPlt100
• Blunt head trauma
• Excluded polytrauma pts
• HTS v LR
• Conclusion
• Both groups received same volume of fluids
• No difference in survival, length of stay,
  neurologic outcome

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Hypertonic Saline

• Wade et al 1997 meta analysis
• 11 studies
• Hypertonic saline alone and with dextran v
  isotonic saline
• No difference for HS v isotonic saline
• HSD showed slight improvement in survival
• Especially with TBI pts and penetrating injuries

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Hypertonic Saline

• US Committee on Fluid Resuscitation for combat
  casualties of Inst of Medicine
• Initial fluid resuscitation of battlefield
  hemorrhage
• 250ml bolus of 7.5 saline

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Hypertonic Saline

• Conclusions
• Many human studies have shown safety of HS
• HS shown to decrease ICP
• HSdextran mortality improvement with head
  trauma resuscitation
• Military use
• May increase bleeding in UCHS
• Insufficient studies to suggest routine use

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Oxygen-carrying blood substitutes

• Fluorocarbon based synthetic oxygen carriers
• Easy to produce
• Long shelf life
• Low immunogenic effects
• Require high FiO2
• Rapid plasma clearance
• Stroma free hemoglobin
• High O2 carrying capacity
• Pro-oncotic effect
• Immunogenic effects
• Renal toxicity
• Short half life

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Conclusion

• Hemorrhagic Shock
• Prehospital Care scoop and run
• Treatment Surgical intervention then fluid to
  prevent acidosis and MOF
• Permissive hypotension More human studies.
• LR v NS no mortality difference
• Crystalloid v Colloid Colloids shown promise in
  sepsis. Possible increased mortality and cost
  limit routine use
• Hypertonic Saline Safe, currently used by
  military. Benefits for head trauma
• Blood substitutes More studies needed

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References

• Kolecki, P. Hypovolemic Shock eMedicine Mar
  2008
• Hardaway, R. A brief review of traumatic shock
  leading to a new theory and new treatment. J
  Applied Research 2003 3464-8
• Mattox, K. Permissive Hypotension. Trauma.org
  2003
• Bozeman, W. Hemorrhagic Shock. eMedicine Jan 2007
• Colwell, C. Management of shock in adult trauma.
  Uptodate.com Jan 2005
• Udeani, J. Hemorrhagic shock eMedicine Mar 2008
• Krausz, M. Initial resuscitation of hemorrhagic
  shock. World J Emerg Surg. 2006 114
• Revell, M. Fluid resuscitation in prehospital
  trauma care a consensus view. Emerg Med J. 2002
  19494-498
• Gutierrez, G. Clinical review Hemorrhagic shock.
• Kreimeier, U. Permissive hypotenison. Schweiz
  Med. 2000 1301516-24

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References

• 11. Kowalenko, T. Improved outcome with
  hypotensive resuscitation of uncontrolled
  hemorrhagic shock in swine model. J Truuma. 1992
  Sep3349-53
• 12. Bickell, W. Immediate v delayed fluid
  resuscitation for hypotensive patients with
  penetrating torso injuries. NEJM 3311105-1109
• 13. Pascoe, S. Management of hypovolemic shock in
  the trauma patient NSW Inst of Trauma and Inj
  management. 2007
• 14. Rob, S. Lactated ringers is superior to
  normal saline in the resuscitation of
  uncontrolled hemorrhagic shock. J Trauma. 2007
• 15. Cochran review 2006
• 16. Boldt, J. Fluid Choice for resuscitation of
  the truuma patient. Can J Anesth. 2004 515
• 17. Svensen, C. Using small volume resuscitation
  in Sweden observations from initial experiences.
  Trans Altern in Transfusion Med 2003 43
• 18. Shot and Dark 1996,1999
• 19. Blood Transfusions. Wekipedia.com