Effects of acid-base correction on hemodynamics, oxygen dynamics, and resuscitability in severe canine hemorrhagic shock

Literature

of resuscitation/Resuscitation

animals (n = 6) were subjected to shock and fibrillation and were resuscitated with volume replacement. Group 3 animals (n = 6) were also subjected to shock and fibrillation but were resuscitated with epinephrine hydrochloride infusion. Group 4 animals (n = 6) were subjected to shock and fibrillation but were resuscitated with cardiopulmonary support. Interventions: The shock was to a mean arterial pressure of 25 mmHg for 1 h followed by 5 min of fibrillation. Group 2 animals were resuscitated for 1 h. Group 3 animals were supported for 6 h on epinephrine after the shock period. Group 4 animals were supported for 1 h on cardiopulmonary support, then were observed for another 5 h. All animals were sedated and intubated, and a median sternotomy was performed. Main Outcomes Measured: Survival, hemodynamic function, lactate production, myocardial blood flow, and water content. Results: Group 1 sheep showed no detrimental effects in any of the measured variables. Group 2 sheep could not be resuscitated. Group 3 sheep could be supported with epinephrine but had a 60% depression in left ventricular function and an ultimately high mortality rate (67%) when the infusion of epinephrine was discontinued. Group 4 sheep had a 100% survival rate and only a 20% deterioration in left ventricular function. Conclusions: Cardiopulmonary support improves survival and preserves left ventricular function compared with volume resuscitation with or without inotropic support in this model of hemorrhagic shock.

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animalsweresubjectedto 90 min of controlled hemorrhagic shock. They were then randomly given a 2.5 ml/kg equimolarinjection of 8.4%sodiumbicarbonate, Carbicarb,or 5.84%hypertonic saline.The sodiumload per kilogram of body weight wasidentical in all three groups. Thirty minutes later, the animals were retransfusedwith the shedblood over 15 mm and further observedfor 120min. Measurements and Main Results: Carbicarb and sodium bicarbonate both significantlyincreasedbicarbonateconcentrationscompared with saline. Arterial and venousblood pH increasedmorewith Carbicarbthan with bicarbonatebut thisincrease. wasnot statisticallysignificant.After shock but beforeretransfusion,all three treatmentsmoderately increased blood pressure,cardiacindex, oxygendelivery index, and oxygen consumptionindex to a similar extent. After retransfusion, blood pressure,cardiac index, andoxygendynamicstemporarily improvedin ail groups,without significant improvementin the bicarbonateand Carbicarb-treatedanimals,despitetheir excellent acid-basestatus.Conclusions:In severecanine hemorrhagicshock,Carbicarb,bicarbonate,and hypertonic salineappearto possess similarhemodynamicpropertiesdespitethe buffering propertiesof bicarbonate and Carbicarb. The similar responsesmay be due to their identical sodiumcontent. Arterial pH correction doesnot appearto further improve the responsesto blood retransfusion.

Effbets of aeid-baae eosreeticm on hemodynamies, oxygen

Immediate versus debtyed fir&d reswxcim sive patients nit& psmt~atiag tom0 ii#rIs

dyn&cs, and restscitability rhagic shock

Bickell WH, Wall MJ Jr, PepePE, Martin RR, Ginger VF, Allen MK, Mattox KL

in severe canine hemor-

fer hypoten-

BenjaminE, Oropello JM, Abalos AM, Hannon EM, Wang JK, FischerE, Iberti TJ

Baylor College oj Medicine, TX 77030, USA

Surgical-KU, Mount Sinai Medical Center, Box 1264, One Gustave L. Levy Place, New York, NY 10029-6574, USA

New Engl. J. Med. 1994;331117:1105-1109 Background: Fluid resuscitationmay be detrimental whengivenbeforebleedingiscontrolled in patientswith trauma.The purposeof this study wasto determinethe effectsof delaying fluid resuscitationuntil the time of operative intervention in hypotensive patients with penetratinginjuries to the torso. Methods. We conducted a prospectivetrial comparing immediateand delayedfiuid resuscitationin 598adultswith penetrating torso injurieswho presentedwith a prehospitalsystolic blood pressurec = 90 mmHg.The study settingwasa city with a singlecentralizedsystemof prehospitalemergency care and a singlereceiving facility for patients with major trauma.Patientsassigned to the immediateresuscitationgroupreceivedstandardfluid resuscitation before they reachedthe hospital and in the trauma center,and thoseassignedto the delayed-resuscitation group receivedintravenouscannulationbut no fluid resuscitationuntil they reachedthe operating room. Re-

Crit. Care Med. 1994;22/10: 1616-1623 Objective: To comparethe effectsof hypertonic saline, sodiumicarbonate,and Carbicarbregisteredtrademark signresuscitationon acid-basebalance,hemodynamics, and oxygen dynamicsin a reperfused,canine hemorrhagic shock model. Design:Prospective,randomized trial. Setting: Laboratory at a university medicalcenter. Subjects:Thirty-five anesthetized,mongrel dogs. Interventions:After the administrationof anesthesia, the dogswereintubated and mechanicallyventilated. Vascular catheterswere insertedinto each femoral artery, for continuousblood pressuremonitoring, intermittent blood sampling,and for establishingcontrolled hemorrhage.A pulmonaryartery catheterwasinsertedvia the right jugular vein. Inhaled and exhaledgaseswerecontinuously analyzedusinga metabolicgasmonitor. The

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