Hypothermia after cesarean delivery and its reversal with lorazepam.
BACKGROUND
Intrathecal morphine can produce hypothermia in animals. This side effect has been reported in humans, but has not been thoroughly studied in obstetrics.


METHODS
We report a series of 14 patients with presumed morphine-induced hypothermia. All patients had post-cesarean temperatures <35.8 degrees C, and complained of associated symptoms of diaphoresis and subjective feeling of being hot. After collecting this series, we determined the incidence of this side effect in an observational study of 100 consecutive patients. All patients had spinal anesthesia with bupivacaine, morphine and fentanyl.


RESULTS
In the case series, four of 14 patients were treated conservatively, and 10 were given lorazepam. Those treated conservatively had 6h of hypothermia and symptoms; women given lorazepam had a cessation of symptoms and a rapid increase in temperature. In the observational study, 6% (95% Confidence Interval: 1-10%) experienced symptomatic hypothermia lasting for several hours after the end of surgery (120-360 min). We found no statistical association with any demographic or obstetric characteristic.


CONCLUSIONS
We conclude that symptomatic hypothermia is an occasional side effect of cesarean section under spinal anesthesia. We believe this syndrome is due to intrathecal morphine. While the duration is limited to 6h, lorazepam appears to treat both hypothermia and symptoms.
Hess
P E
PE
Department of Anesthesia and Critical Care, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA. phess@bidmc.harvard.edu
Snowman
C E
CE
Wang
J
J
D000328:Adult; D000701:Analgesics, Opioid / Q000009:adverse effects*; D000773:Anesthesia, Obstetrical; D000775:Anesthesia, Spinal; D000779:Anesthetics, Local; D002045:Bupivacaine; D002585:Cesarean Section; D005260:Female; D005283:Fentanyl; D006801:Humans; D007035:Hypothermia / Q000139:chemically induced / Q000188:drug therapy*; D008140:Lorazepam / Q000627:therapeutic use*; D009020:Morphine / Q000009:adverse effects*; D010149:Postoperative Pain / Q000188:drug therapy; D011183:Postoperative Complications; D011247:Pregnancy
D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D009020:Morphine; D008140:Lorazepam; D005283:Fentanyl; D002045:Bupivacaine