Cold saline infusion and ice packs alone are effective in inducing and maintaining therapeutic hypothermia after cardiac arrest.
OBJECTIVE
Hypothermia treatment with cold intravenous infusion and ice packs after cardiac arrest has been described and used in clinical practice. We hypothesised that with this method a target temperature of 32-34 degrees C could be achieved and maintained during treatment and that rewarming could be controlled.


METHODS
Thirty-eight patients treated with hypothermia after cardiac arrest were included in this prospective observational study. The patients were cooled with 4 degrees C intravenous saline infusion combined with ice packs applied in the groins, axillae, and along the neck. Hypothermia treatment was maintained for 26 h after cardiac arrest. It was estimated that passive rewarming would occur over a period of 8h. Body temperature was monitored continuously and recorded every 15 min up to 44 h after cardiac arrest.


RESULTS
All patients reached the target temperature interval of 32-34 degrees C within 279+/-185 min from cardiac arrest and 216+/-177 min from induction of cooling. In nine patients the temperature dropped to below 32 degrees C during a period of 15 min up to 2.5h, with the lowest (nadir) temperature of 31.3 degrees C in one of the patients. The target temperature was maintained by periodically applying ice packs on the patients. Passive rewarming started 26 h after cardiac arrest and continued for 8+/-3h. Rebound hyperthermia (>38 degrees C) occurred in eight patients 44 h after cardiac arrest.


CONCLUSIONS
Intravenous cold saline infusion combined with ice packs is effective in inducing and maintaining therapeutic hypothermia, with good temperature control even during rewarming.
Larsson
Ing-Marie
IM
Department of Surgical Sciences, Anaesthesiology & Intensive Care, Uppsala University, Uppsala University Hospital, S-751 85 Uppsala, Sweden. ing-marie.larsson@akademiska.se
Wallin
Ewa
E
Rubertsson
Sten
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001831:Body Temperature; D003080:Cold Temperature; D004562:Electrocardiography; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006323:Heart Arrest / Q000401:mortality / Q000628:therapy*; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D007053:Ice; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011446:Prospective Studies; D017694:Rewarming; D012965:Sodium Chloride / Q000008:administration & dosage*; D016896:Treatment Outcome
D007053:Ice; D012965:Sodium Chloride