Impact of pre-arrest glycemic state induced by prolonged fasting on defibrillation requirements: a prospective porcine model of ventricular fibrillation cardiac arrest.

OBJECTIVE

To investigate whether prolonged fasting-induced lower pre-arrest glycemia above the hypoglycemia alert threshold of 70 mg/dL is associated with defibrillation requirements, CPR duration, and sustained ROSC in a porcine model of ventricular fibrillation cardiac arrest.

METHODS

Twenty male Landrace pigs were randomized to 36 h or 12 h of solid-food fasting with free access to water before ventricular fibrillation induction. After successful ventricular fibrillation induction, animals underwent 8 min of untreated no-flow cardiac arrest followed by standardized mechanical CPR.

RESULTS

Animals in the prolonged fasting group exhibited significantly lower blood glucose levels at all time points. The 36-h fasting group required more defibrillation shocks than the 12-h fasting group, with median values of 2 shocks (2-3.75) and 1 shock (1-1.75), respectively (P = 0.035). CPR duration was also longer in the 36-h fasting group, with median durations of 344 s (238-784.25) and 191 s (145.75-275), respectively (P = 0.043). Sustained ROSC was achieved in 70% and 90% of animals respectively, with no statistically significant difference between groups (P = 0.582). In univariable Poisson regression, higher pre-arrest blood glucose was associated with fewer defibrillation shocks required, with an incidence rate ratio of 0.980 (95% CI, 0.968-0.993; P = 0.002). During CPR, the 36-h fasting group demonstrated significantly lower MAP (P = 0.035) and mixed venous oxygen saturation (P = 0.030) than the 12-h fasting group.

CONCLUSION

In this prospective longitudinal porcine model of ventricular fibrillation cardiac arrest, prolonged fasting-induced lower pre-arrest glycemia within the physiological range was associated with increased defibrillation requirements and longer CPR duration, despite similar rates of sustained ROSC. These findings indicate that pre-arrest glycemic and metabolic status may be relevant to resuscitation difficulty.