Chang Sam S, Jacobs Bruce, Wells Nancy, Smith Joseph A, Cookson Michael S
Department of Urologic Surgery and Patient Care Services, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2765, USA.
J Urol. 2004 Mar;171(3):1077-9. doi: 10.1097/01.ju.0000113229.45185.e5.
Historically obesity has been thought to impact negatively patients undergoing surgery. We evaluated the impact of body mass index (BMI), an objective measure of obesity, on operative and perioperative outcomes in patients undergoing radical cystectomy.
We reviewed the records of 304 consecutive patients who underwent radical cystectomy and urinary diversion between October 1995 and July 2000. Factors analyzed included BMI, clinical demographic characteristics, comorbidities, operative variables (eg estimated blood loss [EBL], transfusion requirement and operative time), length of stay and postoperative complications. Results were analyzed using the nonpaired heteroscedastic Student t test assuming unequal variances to determine statistical significance.
Of the patients 61% were overweight or obese (BMI 25 or greater). BMI did not correlate with type of urinary diversion, gender or race. On univariate analysis the preoperative variables age, American Society of Anesthesiologists score and BMI correlated with EBL. However, on multivariate analysis BMI was the only preoperative or operative variable that significantly correlated with EBL (p = 0.01). Mean EBL in patients with a normal BMI (less than 25) was 595 ml compared to the mean EBL for overweight and obese patients (25 or greater of 811 ml (p <0.001). However, BMI did not correlate with the complication rate or hospital stay.
On multivariate analysis considering preoperative and operative variables BMI was the only preoperative variable that predicted increased blood loss. Despite this finding overweight or obese patients in this series did not have a higher complication rate or longer hospital stay.
长期以来，肥胖一直被认为会对接受手术的患者产生负面影响。我们评估了体重指数（BMI）这一肥胖的客观指标对接受根治性膀胱切除术患者的手术及围手术期结局的影响。
我们回顾了1995年10月至2000年7月期间连续接受根治性膀胱切除术及尿流改道的304例患者的记录。分析的因素包括BMI、临床人口统计学特征、合并症、手术变量（如估计失血量[EBL]、输血需求和手术时间）、住院时间及术后并发症。采用非配对异方差学生t检验分析结果，假设方差不等以确定统计学意义。
61% 的患者超重或肥胖（BMI≥25）。BMI与尿流改道类型、性别或种族无关。单因素分析显示，术前变量年龄、美国麻醉医师协会评分和BMI与EBL相关。然而，多因素分析显示，BMI是唯一与EBL显著相关的术前或手术变量（p = 0.01）。BMI正常（<25）患者的平均EBL为595 ml，而超重和肥胖患者（BMI≥25）的平均EBL为811 ml（p <0.001）。然而，BMI与并发症发生率或住院时间无关。
在考虑术前和手术变量的多因素分析中，BMI是唯一预测失血量增加的术前变量。尽管有这一发现，但本系列中的超重或肥胖患者并发症发生率并未更高，住院时间也未更长。
