Department of Anaesthesia, Freeman Hospital, Newcastle Upon Tyne, United Kingdom.
Ann Surg. 2010 Mar;251(3):535-41. doi: 10.1097/SLA.0b013e3181cf811d.
To investigate the null hypothesis that an objective, noninvasive technique of measuring cardiorespiratory reserve, does not improve the preoperative assessment of patient risk of postoperative complications, when compared with a standard questionnaire-based assessment of functional capacity.
Postoperative complications may be increased in patients with reduced cardiorespiratory function. Activity questionnaires are subjective, whereas cardiopulmonary exercise testing (CPET) provides an objective definition of cardiorespiratory reserve. The use of preoperative CPET to predict postoperative complications is not fully defined.
CPET and an algorithm-based activity assessment (Veterans Activity Questionnaire Index [VASI]) were performed on consecutive patients (n = 171) with low subjective functional capacity (metabolic equivalent score [METS] < 7), being assessed for major surgery. A morbidity survey determined postoperative day 7 complications. Logistic regression defined independent predictors of complication group. Receiver-operating curve (ROC) analysis defined the predictive value of CPET to outcome. P < 0.05 value demonstrated significance.
Objective cardiorespiratory reserve did not differ between operated (n = 116) and nonoperated patients (n = 55). Median complication rate on postoperative day 7 was 1. Patients with >1 complication had an increase in hospital LOS compared to the group with < or =1 complication (26 vs. 10 days; P < 0.001). Anaerobic threshold (AT) was higher in the group with < or =1 complication (11.9 vs. 9.1 mL/kg/min; P = 0.001) and demonstrated high accuracy (AUC = 0.85), sensitivity (88%), and specificity (79%), at an optimum AT of 10.1 mL/kg/min (defined by the furthest left point on the ROC curve). AT, VASI, and surgical reintervention were independent predictors of complication group. Preoperative AT significantly improved outcome prediction when compared with the use of VASI alone.
An objective measure of cardiorespiratory reserve was an independent predictor of a major surgical group with increased postoperative complications and hospital LOS. AT measurement significantly improved outcome prediction compared with an algorithm-based activity assessment.
研究一个假设，即一种客观的、非侵入性的心肺储备测量技术，并不能改善术后并发症风险的术前评估，与基于标准问卷的功能能力评估相比。
心肺功能降低的患者术后并发症可能增加。活动问卷是主观的，而心肺运动试验（CPET）则提供心肺储备的客观定义。术前 CPET 用于预测术后并发症的应用尚未完全确定。
对低主观功能能力（代谢当量评分[METS] < 7）的连续患者（n = 171）进行 CPET 和基于算法的活动评估（退伍军人活动问卷指数[VASI]），评估其进行重大手术的情况。发病率调查确定术后第 7 天的并发症。逻辑回归确定并发症组的独立预测因子。接受者操作特征（ROC）分析定义 CPET 对结果的预测价值。P < 0.05 表示差异具有统计学意义。
手术组（n = 116）和非手术组（n = 55）之间的客观心肺储备没有差异。术后第 7 天的并发症中位数为 1。与并发症组 < 或 = 1 相比，并发症组 > 1 的患者的住院时间延长（26 与 10 天；P < 0.001）。并发症组 < 或 = 1 的患者无氧阈值（AT）更高（11.9 与 9.1 mL/kg/min；P = 0.001），并具有较高的准确性（AUC = 0.85）、敏感性（88%）和特异性（79%），AT 最佳值为 10.1 mL/kg/min（通过 ROC 曲线最左侧的点定义）。AT、VASI 和手术再次干预是并发症组的独立预测因子。与单独使用 VASI 相比，术前 AT 显著改善了术后结果的预测。
心肺储备的客观测量是一个独立的预测指标，预测具有增加术后并发症和住院时间的主要手术患者。与基于算法的活动评估相比，AT 测量显著改善了预后预测。
