The effect of sodium bicarbonate administration on the vasopressor effect of high-dose epinephrine during cardiopulmonary resuscitation in swine

Abstract

Sodium bicarbonate is administered during cardiopulmonary resuscitation (CPR) for the treatment of systemic acidemia. However, the effect of administering standard-dose sodium bicarbonate on the vasopressor effect of epinephrine is unknown. This study compared the effects of sodium bicarbonate or normal saline on the vasopressor effect of epinephrine in 18 pigs. After 10 minutes of unassisted ventricular fibrillation, CPR was started using a pneumatic chest compression device. Two minutes after the start of CPR, sodium bicarbonate (1 mEq/kg) or normal saline (1 mL/kg) was administered into the right ventricule followed 1 minute later by epinephrine (0.2 mg/kg). Defibrillation was attempted at 8 minutes of CPR (18 minutes of ventricular fibrillation). Results demonstrated no significant differences in aortic systolic, aortic diastolic, or coronary perfusion pressure (CPP) between the two groups (1 minute after epinephrine, CPP was 22.6 +/- 13.3 mm Hg versus 21.1 +/- 20.7 mm Hg for the sodium bicarbonate and normal saline groups, respectively). However, when the data were stratified according to pH < 7.4 and pH > 7.4, the peak change in CPP was 12.7 +/- 21 mm Hg when pH < 7.4 and was 5.2 +/- 7.4 when pH > 7.4 (P = .33). Resuscitation was also similar between the two groups (two of nine for sodium bicarbonate and one of nine for normal saline). In conclusion, the standard recommended dose of sodium bicarbonate did not alter the vasopressor effect of epinephrine or resuscitation compared with normal saline in this closed chest model of ventricular fibrillation and CPR.

Sodium Bicarbonate and Calcium Chloride for the Treatment of Hyperkalemia-Induced Cardiac Arrest: A Randomized, Blinded, Placebo-Controlled Animal Study*

“…It is unknown whether the protective effect of NaH co 3 in the current study is generalizable to cardiac arrest in general. Previous nonhyperkalemic animal studies have reported conflicting results with some studies showing harm (18, 19), some finding no effect (20–22), and some finding a beneficial effect (23–26) of NaH co 3 administration. Clinical studies in patients without hyperkalemic cardiac arrest have been equally conflicting with three small, randomized trials finding no effect, and observational studies demonstrating different results (27–33).…”

Approaches to modern management of cardiac arrest

“…62These findings were challenged by Bleske et al who argued that the doses used in the earlier studies were much larger than those in clinical practice (1 mEq/kg) 63…”

European Resuscitation Council Guidelines 2000 for Adult Advanced Life Support

“…Much of the evidence against the routine use of bicarbonate is based on animal studies and may have limited applicability to humans as the doses of bicarbonate used have often been high. [93][94][95] One prospective randomised controlled trial has been reported on the use of buffers in patients with out of hospital cardiac arrest. 96 The buffer used was Tribonat (a mixture of sodium bicarbonate, trometamol, disodium phosphate, and acetate).…”