Persistent Hypothermia and Excessive Sweating Following Intrathecal Morphine Administration in a Teenage Boy: A Case Report

INTRODUCTION: Opioids are used intrathecally to manage surgical pain. There are few reports of hypothermia after spinal morphine injection, none in the pediatric population. We present a teenager’s case of mild hypothermia. CASE PRESENTATION: A 15-year-old boy was scheduled for elective abdominal laparotomy. General anesthesia was combined with spinal anesthesia, using levobupivacaine and morphine. In the recovery room, he presented a decreased tympanic temperature (34.4°C) associated with excessive sweating, hyperglycemia, and complained of feeling hot. All other vital signs were normal. It was decided to maintain clinical vigilance and hourly monitoring of temperature and glycaemia values. Despite active warming, he remained hypothermic for 16 hours, with gradual remission of symptoms and normalization of glycemic values. It is unknown how intrathecal morphine causes hypothermia. The most viable hypothesis is its effect on the hypothalamus. In our case the most probable causes of post anesthesia hypothermia were excluded; therefore, we can admit that the cause of hypothermia was the spinal administration of morphine. Some reports used naloxone and lorazepam successfully. In our report, they disappeared spontaneously 16 hours later, which corroborates our diagnosis. CONCLUSIONS: Children undergoing subarachnoid block with with intrathecal morphine may develop a disruption on thermoregulation, leading to a resistant postoperative hypothermia associated with excessive sweating.