Work capacity of the bladder during voiding: a novel method to evaluate bladder contractile function

• 作 者: Ning Liu Li-Bo Man Feng He
• 机 构: Department of Urology,Beijing Jishuitan Hospital,Beijing 100035,China
• 出 处: 华夏医学论坛·泌尿生殖2015暨亚太性医学年会2015
• 发表日期: 2015年6期
• 关键词: Bladder voiding contractile function bladder obstruction

　　Background: Work in voiding(WIV)of the bladder may be used to evaluate bladder status throughout urination,not just at a single time point.Few studies,however,have assessed WIV due to the complexity of the calculations.We have developed a method of calculating work capacity of the bladder while voiding and analyzed the associations of bladder work parameters with bladder contractile function and bladder outlet obstruction(BOO).Methods: The study retrospectively evaluated 160 males,aged >40 years and with a detrusor pressure at maximal flow rate(PdetQmax)of ≥40 cmH2O,who underwent urodynamic testing.WIV was calculated using the bladder power integration method;WIV per second(WIV/t)and WIV per liter urine voided(WIV/v)were also calculated.The relationships between these work capacity parameters and PdetQmax and AG number were determined using linearby-linear association tests,and relationships between work capacity parameters and BOO grade were investigated using Spearmans association test.Results: Mean WIV was 1.15±0.78 J,mean WIV/t was 22.95±14.45 milliWatt,and mean WIV/v was 5.59±2.32 J/L.WIV/v showed significant positive associations with PdetQmax(r=0.845,P=0.000),AG number(r=0.814,P=0.000),and Schafer class(r=0.726,P=0.000).Conversely,WIV and WIV/t showed no associations with PdetQmax or AG number.In patients with BOO(Schafer class > Ⅱ),WIV/v correlated positively with increasing BOO grade.Conclusions: WIV can be calculated from simple urodynamic parameters using the bladder power integration method.WIV/v may be a marker of both bladder contractile function and BOO.