Regional blood flow during cardiopulmonary resuscitation in dogs using simultaneous and nonsimultaneous compression and ventilation.

Abstract

SUMMARY We studied regional blood flow (QR) using radiolabeled microspheres and measured hemodynamic variables in 20 anesthetized dogs in normal sinus rhythm and during ventricular fibrillation treated with cardiopulmonary resuscitation (CPR). Nonsimultaneous compression and ventilation CPR (NSCV-CPR) was performed in seven dogs with a pneumatic piston that gave 50 chest compressions/min with an open airway with 10 ventilations at an airway pressure of 33 mm Hg interposed between each fifth and sixth compression. Simultaneous compression and ventilation (SCV-CPR) was performed in seven dogs with the piston and in six other dogs with a circumferential pneumatic vest. Both devices gave 30 compressions/min simultaneously with 30 ventilations that elevated airway pressure to 80 mm Hg. The abdomen was bound during SCV-CPR. Regional blood flow (mean SD) to the cerebral hemispheres, cardiac ventricles, and kidneys, expressed as ml/min/100 g tissue, was 3.1 + 4.0, 3.4 3.3 and 1.5 1.5, respectively, during NSCV-CPR; 11.5 + 5.9, 4.9 4.7 and 2.7 2.7 during SCV-CPR (vest); and 16.2 + 7.2, 11.0 4.0 and 20.1 20.2 during SCV-CPR (piston) (all p < 0.05 compared with NSCV-CPR). These results indicate that QR to all organs studied is reduced below normal sinus rhythm levels during CPR for ventricular fibrillation, QR to the brain is proportionately greater than QR to the heart and kidneys, and QR to the brain is greater with both forms of SCV-CPR than with NSCV-CPR.BECAUSE cardiopulmonary arrest is one of the greatest stresses the body can suffer, the success of cardiopulmonary resuscitation (CPR) depends upon maintaining vital organ perfusion at a level consistent with full recovery of function after resuscitation. Conventional or nonsimultaneous ventilation and compression CPR (NSCV-CPR) fibrillation (VF) treated with NSCV-CPR and two forms of SCV-CPR. MethodsTwenty adult mongrel dogs, mean weight 23.7 kg, unselected for chest configuration, were studied. Anesthesia was induced with thiopental sodium (1 g) and maintained with ketamine (mean dose 0.6 + 0.3 g; mean time of administration after thiopental 89 + 44 minutes). The dogs were intubated with an endotracheal tube, the proximal end of which extended 2-4 cm outside the mouth. The cuff was inflated to achieve an airtight seal; the exact amount of air inserted was not measured.

Cardiopulmonary Resuscitation With Chest Compressions During Sustained Inflations

“…Our results are supported by other largeanimal studies, which have demonstrated that simultaneous CCs and ventilation generates higher intrathoracic and vascular pressure and enhances myocardial and cerebral perfusion. 9,10,19,20,[25][26][27] Similar observations in regard to increased blood pressure and carotid blood flow during simultaneous CCs and ventilation have been reported in a human trial. 10 In contrast, interrupting CCs to deliver manual inflations resulted in substantial decreases in the aortic diastolic pressures and coronary perfusion pressures.…”

Assessment of In-Hospital Cardiopulmonary Resuscitation Using Utstein Template in a University Hospital

“…Resuscitation time is considered to reflect the severity of ischemic injuries before and during CPR. Some investigators have estimated that, when CPR is begun immediately, cerebral blood flow is 3-15% of normal (Koehler et al 1963;Luce et al 1983;Jackson et al 1984) but decreases progressively as CPR continues (Sharaff et al 1984) and intracranial pressures rise (Guerci et al 1981;Bircher and Safar 1984). Nevertheless, acceptable neurological recovery has been reported even after prolonged CPR (Krug 1986).…”

Cardiac, thoracic, and abdominal pump mechanisms in cardiopulmonary resuscitation: Studies in an electrical model of the circulation

“…This approach has been advocated recently, much more strongly than in the past [7,20] because of accumulating evidence that standard CPR may generate inadequate perfusion of the heart in animals [21,22] and that present CPR techniques produce little improvement in resuscitation rates and long-term survival in human beings [23,24].…”