Vitamin C may reduce the duration of mechanical ventilation in critically ill patients: a meta-regression analysis
Vitamin C may reduce the duration of mechanical ventilation in critically ill patients: a meta-regression analysis
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DOI：
10.1186/s40560-020-0432-y
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发表时间：
2020-02-07
影响因子：
7.1
通讯作者：
Chalker, Elizabeth
中科院分区：
文献类型：
--
作者：
Hemila, Harri;Chalker, Elizabeth
背景：我们最近的Meta分析表明，维生素C可以缩短ICU的住院时间和机械通气的时间。在这里，我们通过对照组的换气时间(我们将其作为每个试验中患者疾病严重程度的替代指标)来分析维生素C对换气时间的影响。方法计算机检索MEDLINE、Scope us、Cochrane中央对照试验数据库及相关文献的参考文献目录。我们纳入了对照试验，在这些试验中，研究组之间唯一的区别是服用维生素C。我们的研究并不局限于随机试验，也不需要安慰剂对照。我们包括所有剂量和所有持续时间的维生素C给药。一位作者从试验报告中提取了研究特点和结果，并将数据输入电子表格。两位作者都对照原始报告核对了输入的数据。在对照组中，我们使用Meta回归检验维生素C对呼吸机时间的影响是否依赖于呼吸机持续时间。结果我们确定了9项可能符合条件的试验，其中8项纳入荟萃分析。我们汇总了8项试验的结果，总共685名患者，发现维生素C平均缩短了14%的机械通气时间(P=0.00001)。然而，在两个试验之间，维生素C的作用存在显著的异质性。未经治疗的对照组的通气时间完全解释了异质性。维生素C对呼吸时间最长的患者最有益，与病情最严重的患者相对应。在5项试验中，包括471名需要呼吸机超过10小时的患者，每天服用1-6g维生素C可平均缩短25%的呼吸机时间(P<；0.0001)。结论我们发现强有力的证据表明维生素C可以缩短机械通气的时间，但其影响的大小似乎取决于未治疗的对照组的机械通气时间。在进一步研究中应考虑基线疾病严重程度的水平。不同的剂量应该在未来的试验中直接进行比较。
Background Our recent meta-analysis indicated that vitamin C may shorten the length of ICU stay and the duration of mechanical ventilation. Here we analyze modification of the vitamin C effect on ventilation time, by the control group ventilation time (which we used as a proxy for severity of disease in the patients of each trial). Methods We searched MEDLINE, Scopus, and the Cochrane Central Register of Controlled Trials and reference lists of relevant publications. We included controlled trials in which the administration of vitamin C was the only difference between the study groups. We did not limit our search to randomized trials and did not require placebo control. We included all doses and all durations of vitamin C administration. One author extracted study characteristics and outcomes from the trial reports and entered the data in a spreadsheet. Both authors checked the data entered against the original reports. We used meta-regression to examine whether the vitamin C effect on ventilation time depends on the duration of ventilation in the control group. Results We identified nine potentially eligible trials, eight of which were included in the meta-analysis. We pooled the results of the eight trials, including 685 patients in total, and found that vitamin C shortened the length of mechanical ventilation on average by 14% (P = 0.00001). However, there was significant heterogeneity in the effect of vitamin C between the trials. Heterogeneity was fully explained by the ventilation time in the untreated control group. Vitamin C was most beneficial for patients with the longest ventilation, corresponding to the most severely ill patients. In five trials including 471 patients requiring ventilation for over 10 h, a dosage of 1-6 g/day of vitamin C shortened ventilation time on average by 25% (P < 0.0001). Conclusions We found strong evidence that vitamin C shortens the duration of mechanical ventilation, but the magnitude of the effect seems to depend on the duration of ventilation in the untreated control group. The level of baseline illness severity should be considered in further research. Different doses should be compared directly in future trials.