亚低温治疗对重型颅脑损伤患者PtbO₂梯度的影响

The Effects of Therapeutic Hypothermia on Changes in Partial Pressure of Brain Tissue Oxygen (PbtO₂) Gradients for Patients with Severe Traumatic Brain Injury—Hypothermia on Partial Pressure of Brain Tissue Oxygen

摘要: 目的：研究亚低温治疗对重型颅脑损伤患者半球脑组织氧分压(partial pressure of brain tissue oxygen, PbtO₂)梯度的影响。方法：采用无创性选择性脑亚低温(头颈部降温法)治疗方法，将送至本院的60重型颅脑损伤手术后收住入病房患者随机分为亚低温组(治疗组)和常温(对照组)。亚低温治疗组采用亚低温治疗仪和降温毯继续亚低温治疗，采用头颈部降温为主，保持脑温(下述)在33℃~35℃左右，亚低温治疗维持伤后5天。对照组使用降温方法保持患者体温在正常范围内。两组患者在麻醉后行均双侧额部钻颅置入光导纤维传感器于额叶脑实质内，行两侧大脑半球脑组织氧分压梯度监护(健侧PbtO₂-伤侧PbtO₂)，同时监测动脉血气分析、血压、脉搏、呼吸、血氧饱和度、中心静脉压和颅内压(ICP)监测。并前瞻性分析比较两组患者手术后的半球脑组织氧分压梯度、6月后的GOS评分和主要并发症(如感染、血小板减少、消化道出血、电解质紊乱等)。结果：亚低温组在治疗后24、48和72 h的大脑半球PtbO₂梯度、颅内压均较对照组明显降低；亚低温组恢复良好率、病死率与常温组相比较有显著差异(P < 0.05)，预后较佳(GOS评分4~5分)率明显好于常温组(P < 0.05)。未发生与亚低温治疗相关的严重并发症。结论：无创性选择性脑亚低温方法治疗重型颅脑损伤患者简单、方便、有效，具有改善PbtO₂梯度，降低颅内压、改善预后的作用。亚低温治疗后可改善局部脑组织缺氧状态。

Abstract: Objective: To investigate the effects of therapeutic hypothermia on changes in partial pressure of brain tissue oxygen (PbtO₂) gradients for patients with severe traumatic brain injury (TBI). Methods: Sixty in-patients with severe TBI after unilateral craniotomy were randomized into a therapeutic hypothermia group with the brain temperature maintained at 33 - 35 degrees Celsius for 5 days using mild hypothermia therapeutic apparatus or cooling blankets, and a normothermia control group in the intensive care unit. The fibres were introduced into the brain parenchyma of the bilateral frontal lobes after general anesthesia, then monitor the PtbO₂ of two sides cerebral hemisphere (uninjured side PbtO₂-injured side PbtO₂). In the meantime, the arterial blood gas analysis, blood pressure, pulse, breath rate, blood oxygen saturation, central venous pressure and intracranial pressure (ICP) were observed and measured during treatment, and the complications (including pulmonary infections, thrombocytopenia defined as platelet count < 100 × 109/L, hemorrhage in the digestive tract, electrolyte disorders and renal malfunction) as well as the Glasgow outcome scale and PbtO₂ were evaluated at 6 months after injury. Results: The mean intracranial pressure values and PtbO₂ gradient in the therapeutic hypothermia group at 24, 48, and 72 hours after treatment were much lower than those of the control group. There are significant difference between the therapeutic hypothermia group and the control group about the mean good recovery rate and the mortality rates (P < 0.05), and the recovery rate (GOS grades 4 - 5 scores) in the therapeutic hypothermia is much better than the country group (P < 0.05). Complications were managed without severe sequelae in the therapeutic hypothermia group. Conclusions: In conclusion, the noninvasive selective mild hypothermia therapy is a simple, convenient, effective way to treat patients with severe TBI. It can also improve PbtO₂ gradient, reduce intracranial pressure and improve prognosis. The local brain tissue hypoxia state will be improved after mild hypothermia therapy.