Cold infusions alone are effective for induction of therapeutic hypothermia but do not keep patients cool after cardiac arrest☆
Received 13 July 2006; received in revised form 17 August 2006; accepted 29 August 2006.
Summary
Aim of the study
Cold infusions have proved to be effective for induction of therapeutic hypothermia after cardiac arrest but so far have not been used for hypothermia maintenance. This study investigates if hypothermia can be induced and maintained by repetitive infusions of cold fluids and muscle relaxants.
Material and methods
Patients were eligible, if they had a cardiac arrest of presumed cardiac origin and no clinical signs of pulmonary oedema or severely reduced left ventricular function. Rocuronium (0.5mg/kg bolus, 0.5mg/kg/h for maintenance) and crystalloids (30ml/kg/30min for induction, 10ml/kg every 6h for 24h maintenance) were administered via large bore peripheral venous cannulae. If patients failed to reach 33±1°C bladder temperature within 60min, endovascular cooling was applied.
Results
Twenty patients with a mean age of 57 (±15) years and mean body mass index of 27 (±4)kg/m2 were included (14 males). Mean temperature at initiation of cooling (median 27 (IQR 16; 87)min after admission) was 35.4 (±0.9)°C. In 13 patients (65%) the target temperature was reached within 60min, 7 patients (35%) failed to reach the target temperature. Maintaining the target temperature was possible in three (15%) patients and no adverse events were observed.
Conclusion
Cold infusions are effective for induction of hypothermia after cardiac arrest, but for maintenance additional cooling techniques are necessary in most cases.
ABSTRACT