Analysis of rebound intracranial pressure occurring during rewarming after therapeutic hypothermia in traumatic brain injury patients

Objective: To investigate the risk factors associated with rebound intracranial pressure (ICP), a phenomenon that occurs when brain swelling reprogresses rapidly during rewarming in patients who have undergone therapeutic hypothermia for traumatic brain injury (TBI).Methods: This study analyzed 42 patients who underwent therapeutic hypothermia among 172 patients with severe TBI admitted to a single regional trauma center between January 2017 and December 2020. Forty-two patients were classified into 34.5 degrees C (mild) and 33 degrees C (moderate) hypothermia groups according to the thera-peutic hypothermia protocol for TBI. Rewarming was initiated post-hypothermia, wherein ICP was maintained at <= 20 mmHg and cerebral perfusion pressure was maintained at >= 50 mmHg for >= 24 h. In the rewarming protocol, the target core temperature was increased to 36.5 degrees C at 0.1 degrees C/h.Results: Of the 42 patients who underwent therapeutic hypothermia, 27 did not survive: 9 in the mild and 18 in the moderate hypothermia groups. The moderate hypothermia group had a significantly higher mortality rate than the mild hypothermia group (p = 0.013). Rebound ICP occurred in 9 of 25 patients: 2 in the mild and 7 in the moderate hypothermia groups. In the risk factor analysis of rebound ICP, only the degree of hypothermia was statistically significant, and rebound ICP was observed more frequently in the moderate than in the mild hy-pothermia group (p = 0.025).Conclusions: In patients who underwent rewarming after therapeutic hypothermia, rebound ICP presented a higher risk at 33 degrees C than at 34.5 degrees C. Therefore, more careful rewarming is needed in patients receiving thera-peutic hypothermia at 33 degrees C.

Automated summary

This study aimed to investigate the risk factors associated with rebound intracranial pressure (ICP) in patients undergoing therapeutic hypothermia for traumatic brain injury (TBI). The results showed that patients in the 33 degrees C hypothermia group had a higher risk of rebound ICP compared to those in the 34.5 degrees C group. Therefore, careful rewarming is necessary for patients receiving therapeutic hypothermia at 33 degrees C.