Intrathecal morphine can produce hypothermia after cesarean delivery, likely due to a central effect on opioid receptor for thermoregulation. The incidence is about 6% to 7% in elective cesarean cases and may be dose dependent.1 In a randomized double-blind controlled study, all parturients received spinal anesthesia containing 150 µg morphine or normal saline in addition to 10 to 12 mg bupivacaine for cesarean delivery. In both groups, a significant decrease in core temperature was noted. The patients in morphine group had lower temperature and longer duration of temperature decrease.2 Prompt management of morphine-induced hypothermia can improve patient’s comfort. After lorazepam administration, immediate cessation of symptoms and an increase to normothermia temperature within 90 minutes were often observed.1 Untreated hypothermia may last up to 6 hours.
Core temperature <35.8°C (<96.4°F).
Paradoxical symptoms: diaphoresis, subjectively feeling of being hot.
Can be sedated or feel dizzy.
Hypothermia is usually identified after cesarean delivery while in the recovery room.
Treatment for Hypothermia After Neuraxial Morphine1
Conservative treatment: In mild cases, warm blankets, heating lamps, and Bair hugger forced hot air warmer; however, patients often feel uncomfortable with heat.
Medication: For moderate and severe hypothermia, lorazepam 0.5 mg, intravenously, may be repeated once.
Naloxone 40 to 80 µg can also be effective in some patients.
J. Hypothermia after cesarean delivery and its reversal with lorazepam. Int J Obstet Anesth.
et al. A randomised double-blind controlled study evaluating the hypothermic effect of 150 µg morphine during spinal anaesthesia for caesarean section. Anaesthesia