Hemodynamic and metabolic parameters during prolonged cardiac arrest and reperfusion by extracorporeal circulation.

Extracorporeal membranous oxygenation (ECMO) is increasingly used in the management of refractory cardiac arrest. Our aim was to investigate early effects of ECMO after prolonged cardiac arrest. In fully anesthetized swine (48 kg, N=18) ventricular fibrillation (VF) was induced and untreated period (20 min) of cardiac arrest commenced, followed by 60 min extracorporeal reperfusion (ECMO flow 100 ml/kg.min). Hemodynamics, arterial blood gasses, plasma potassium, tissue oximetry (StO(2)) and cardiac (EGM) and cerebral (BIS) electrophysiological parameters were continuously recorded and analyzed. Within 3 minutes of VF hemodynamic and oximetry parameters fall abruptly while metabolic parameters destabilize gradually over 20 minutes peaking at pH 7.04 ± 0.05, pCO(2) 89 ± 14 mmHg, K(+) 8.5 ± 1.6 mmol/l. During reperfusion most parameters restore rapidly: within 3-5 minutes mean arterial pressure reaches >40 mmHg, StO(2)>50 %, paO(2)>100 mmHg, pCO(2)<50 mmHg, K(+)<5 mmol/l. EGMs mean amplitude peaks at 4.5 ± 2.4 min. Cerebral activity (BIS>60) reappeared in 5 animals after 87 ± 21 min. In 12/18 animals return of spontaneous circulation was achieved. In conclusions, ECMO provides rapid restitution of internal milieu even after prolonged arrest. However, despite normalization of global parameters full recovery was not guaranteed since cardiac and cerebral electrical activities were sufficiently restored only in some animals. More sensitive and organ specific indicators need to be identified in order to estimate adequacy of cardiac support devices.

Experience of a patient with an extracorporeal ventricular assist system who participated in a sleepover program.

A 19-year-old woman suffered fulminant myocarditis owing to a mycoplasma infection and was inserted with an intra-aortic balloon pump and a percutaneous cardiopulmonary support. Antibiotics and gamma globulin were administered, however, the patient's cardiac function did not recover, and the TOYOBO ventricular assist device (VAD) was implanted. She had rehabilitation training such as maintaining a standing position at the bedside and walking in the hospital, and a hospital outing program to a family restaurant was conducted two times with the VAD. The patient wished to attend the coming-of-age ceremony in Tachikawa city, which is 3 h away from our hospital by car. Therefore, we planned the program including a night stay at her home. The patient and her family fully understood the risks and wished to participate in the sleepover program. In preparing for the sleepover, the patient and her family learned to operate the VAD, and she was able to move to the lavatory and through the house with the help of only her family. A physician and a clinical engineer stayed at her house for infusion of antibiotics and management of sudden changes. There was no adverse event. In Japan, the community support of patients with VAD is not yet established, and we hope that our experience becomes a help to support return to society for patients with VAD.