METHODS: We carried out a secondary analysis of a multicenter prospective observational study involving adult invasively ventilated patients with traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), intracranial hemorrhage (ICH), or ischemic stroke (IS). PaCO2 was collected on day 1, 3, and 7 from ICU admission. Normocapnia was defined as PaCO2 > 35 and to 45 mmHg; mild hypocapnia as 32-35 mmHg; severe hypocapnia as 26-31 mmHg, forced hypocapnia as < 26 mmHg, and hypercapnia as > 45 mmHg.
RESULTS: 1476 patients (65.9% male, mean age 52 ± 18 years) were included. On ICU admission, 804 (54.5%) patients were normocapnic (incidence 1.37 episodes per person/day during ICU stay), and 125 (8.5%) and 334 (22.6%) were mild or severe hypocapnic (0.52 and 0.25 episodes/day). Forced hypocapnia and hypercapnia were used in 40 (2.7%) and 173 (11.7%) patients. PaCO2 had a U-shape relationship with in-hospital mortality with only severe hypocapnia and hypercapnia being associated with increased probability of in-hospital mortality (omnibus p value = 0.0009). Important differences were observed across different subgroups of ABI patients.
CONCLUSIONS: Normocapnia and mild hypocapnia are common in ABI patients and do not affect patients\' outcome. Extreme derangements of PaCO2 values were significantly associated with increased in-hospital mortality.
方法:我们对一项多中心前瞻性观察研究进行了二次分析,该研究涉及成人创伤性脑损伤(TBI)的侵入性通气患者,蛛网膜下腔出血(SAH),颅内出血(ICH),或缺血性卒中(IS)。在第1、3和7天从ICU入院收集PaCO2。正常碳酸血症定义为PaCO2>35和45mmHg;轻度低碳酸血症为32-35mmHg;重度低碳酸血症为26-31mmHg,强制低碳酸血症<26mmHg,高碳酸血症>45mmHg。
结果:1476例患者(65.9%为男性,包括平均年龄52岁[公式:见正文]18岁)。入住ICU时,804例(54.5%)患者的发病率正常(ICU住院期间每人每天1.37次),125例(8.5%)和334例(22.6%)为轻度或重度低碳酸血症(0.52和0.25次/天)。40例(2.7%)和173例(11.7%)患者使用了强制低碳酸血症和高碳酸血症。PaCO2与院内死亡率呈U型关系,只有严重的低碳酸血症和高碳酸血症与院内死亡率的增加相关(综合p值=0.0009)。在ABI患者的不同亚组之间观察到重要差异。
结论:正常碳酸血症和轻度低碳酸血症在ABI患者中很常见,不影响患者的预后。PaCO2值的极端紊乱与住院死亡率的增加显着相关。