The Effectiveness of Target Temperature Management on Poor-Grade Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis.

The effectiveness of target temperature management (TTM) in poor-grade aneurysmal subarachnoid hemorrhage (aSAH) remains a topic of debate. In order to assess the clinical efficacy of TTM in patients with poor-grade aSAH, we conducted a systematic review and meta-analysis. This research was registered in PROSPERO (CRD42023445582) and included all relevant publications up until October 2023. We compared the TTM groups with the control groups in terms of unfavorable outcomes (modified Rankin scale [mRS] score > 3), mortality, delayed cerebral ischemia (DCI), cerebral vasospasm (CVS), and specific complications. Subgroup analyses were performed based on country, study type, follow-up time, TTM method, cooling maintenance period, and rewarming rate. Effect sizes were calculated as relative risk (RR) using random-effect or fixed-effect models. The quality of the articles was assessed using the methodological index for non-randomized studies scale. Our analysis included a total of 5 clinical studies (including 1 randomized controlled trial) and 219 patients (85 in the TTM group and 134 in the control group). Most of the studies were of moderate quality. TTM was found to be associated with a statistically significant improvement in mortality (mRS score 6) rates compared with the control group (RR = 0.61, 95% confidence interval [CI]: 0.40-0.94, p = 0.026). However, there was no statistically significant difference in unfavorable outcomes (mRS 4-6) between the TTM and control groups (RR = 0.94, 95% CI: 0.71-1.26, p = 0.702). The incidence of adverse events, including DCI, CVS, pneumonia, cardiac complications, and electrolyte imbalance, did not significantly differ between the two groups. In conclusion, our overall results suggest that TTM does not significantly reduce unfavorable outcomes in poor-grade aSAH patients. However, TTM may decrease mortality rates. Preoperative TTM may cause patients to miss the opportunity for surgery, although it temporarily protects the brain. Furthermore, the incidence of adverse events was similar between the TTM and control groups.