ECMO improves survival following cardiogenic shock due to carbon monoxide poisoning - an experimental porcine model.

BACKGROUND: Severe intoxication with carbon monoxide (CO) is extremely lethal and causes numerous deaths due to cardiac or respiratory failure. Conventional intensive treatment may not be sufficient. The aim of this study was to investigate the treatment effect of extracorporeal veno-arterial extracorporeal membrane oxygenation (ECMO) following severe CO poisoning in an experimental porcine model.

METHODS: A total of twelve pigs were anaesthetized, routinely monitored and intoxicated by inhalation of CO until the beginning of cardiac failure and randomized to a treatment (ventilator using an FiO2 of 100% or ECMO). In the case of cardiac arrest, advanced resuscitation using standard guidelines was performed for at least 10 min. ECMO was also initiated in the ventilation group if the return of spontaneous circulation did not occur within 10 min. Lung tissue biopsies were obtained before and after CO intoxication.

RESULTS: All animals in the ECMO group survived; however, one had to be resuscitated due to cardiac arrest. A single animal survived in the ventilator group, but five animals suffered from cardiac arrest at an average of 11.8 min after initiation of treatment. Conventional resuscitation failed in these animals, but four animals were successfully resuscitated after the establishment of ECMO. A significant decrease was noticed in PO2 with increasing HbCO, but there was no increase in pulmonary vascular resistance. No differences in H&E-stained lung tissue biopsies were observed.

CONCLUSIONS: The use of ECMO following severe CO poisoning greatly improved survival compared with conventional resuscitation in an experimental porcine model. This study forms the basis for further research among patients.