Abdul Aziz Khairul Anuar, Meduoye Ayo
Department of Cardiothoracic Surgery, Glenfield Hospital, Leicester, LE3 9PQ, UK.
Interact Cardiovasc Thorac Surg. 2010 Feb;10(2):271-82. doi: 10.1510/icvts.2009.214130. Epub 2009 Nov 13.
A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether pH-stat or alpha-stat is the best technique to follow in patients undergoing deep hypothermic circulatory arrest. Altogether 206 papers were found using the reported search, of which 16 represent the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Excluding one paper which provided inconclusive results, six studies found better cerebrovascular metabolism with alpha-stat while three studies found better cerebrovascular metabolism with pH-stat. Four other studies showed no significant difference in the cerebrovascular metabolism between the two acid-base management strategies in patients undergoing deep hypothermic circulatory arrest. Nine studies compared the neuropsychological outcome in patients who underwent deep hypothermic circulatory arrest with three studies supporting each alternative conclusion of preference towards alpha-stat or pH-stat management. The remaining three studies showed no significant difference between the two groups of acid-base management. Comparing the 16 studies based on the age of the patients studied, three out of the four papers which demonstrated that the pH-stat method is a better strategy to improve intraoperative and postoperative outcome were based on a sample of paediatric patients. Conversely, all seven papers that suggested alpha-stat method is associated with better intraoperative and postoperative outcome were based on studies done on adult patients. The remaining four papers suggested no significant difference between the pH-stat group and alpha-stat group. In conclusion, there is evidence to suggest that the best technique to follow in the management of acid-base in patients undergoing deep hypothermic circulatory arrest during cardiac surgery is dependent upon the age of the patient with better results using pH-stat in the paediatric patient and alpha-stat in the adult patient.
一篇心脏外科的最佳证据主题文章是根据结构化协议撰写的。所探讨的问题是，在接受深低温循环停搏的患者中，pH 稳态或α稳态哪种技术是最佳选择。通过报告的检索共找到 206 篇论文，其中 16 篇代表回答该临床问题的最佳证据。这些论文的作者、期刊、发表日期、国家、研究的患者群体、研究类型、相关结局和结果都列成了表格。排除一篇结果不确定的论文后，六项研究发现α稳态下脑血管代谢更佳，而三项研究发现 pH 稳态下脑血管代谢更佳。另外四项研究表明，在接受深低温循环停搏的患者中，两种酸碱管理策略在脑血管代谢方面无显著差异。九项研究比较了接受深低温循环停搏患者的神经心理学结局，三项研究支持α稳态或 pH 稳态管理的各自偏好结论。其余三项研究表明两组酸碱管理之间无显著差异。根据所研究患者的年龄对这 16 项研究进行比较，表明 pH 稳态方法是改善术中和术后结局的更好策略的四篇论文中有三篇基于儿科患者样本。相反，表明α稳态方法与术中和术后更好结局相关的七篇论文均基于对成年患者的研究。其余四篇论文表明 pH 稳态组和α稳态组之间无显著差异。总之，有证据表明，在心脏手术中接受深低温循环停搏的患者进行酸碱管理的最佳技术取决于患者年龄，儿科患者使用 pH 稳态效果更好，成年患者使用α稳态效果更好。
