Preoperative predictors of blood loss at the time of radical prostatectomy: results from the SEARCH database

Abstract

The literature contains conflicting data on preoperative predictors of estimated blood loss (EBL) at radical retropubic prostatectomy (RRP). We sought to examine preoperative predictors of EBL at the time of RRP among patients from the SEARCH database to lend clarity to this issue. A total of 1154 patients were identified in the SEARCH database who underwent RRP between 1988 and 2008 and had EBL data available. We examined multiple preoperative factors for their ability to predict EBL using multivariate linear regression analysis. Median EBL was 900 ml (s.d. 1032). The 25th and 75th percentile for EBL were 600 and 1500 ml, respectively. EBL increased significantly with increasing body mass index (BMI) and increasing prostate size and decreased with more recent year of RRP (all Po0.001). The mean-adjusted EBL in normal-weight men (BMIo25 kg/m 2 ) was 807 ml compared to 1067 ml among severely obese men (BMIX35 kg/m 2 ). Predicted EBL for men with the smallest prostates (o20 g) was 721 ml, compared to 1326 ml for men with prostates X100 g. Finally, statistically significant differences between centers were observed, with mean-adjusted EBL ranging from 844 to 1094 ml. Both BMI and prostate size are predictors of increased EBL. Prostate size is of particular note, as a nearly twofold increased EBL was seen from the smallest (o20 g) to the largest prostates (X100 g). Over time, average EBL significantly decreased. Finally, significant differences in EBL were observed between centers. Patients with multiple risk factors should be forewarned they are at increased risk for higher EBL, which may translate into a greater need for blood transfusion.

Advantages of Robot-Assisted Laparoscopic Radical Prostatectomy in Obese Patients: Comparison with the Open Procedure

“…Our findings of greater EBL in obese patients who underwent RRP are similar to those of previous studies [5-8]. Castle et al [27] reported a significant difference in operative time and blood loss according to BMI in 140 patients undergoing RALP.…”

“…However, obesity may be a complicating factor in retropubic radical prostatectomy (RRP), resulting in higher complication rates, greater blood loss, higher transfusion rates, and worse functional results [5-8]. …”

Effect of positive end‐expiratory pressure on blood loss during retropubic and robot‐assisted laparoscopic radical prostatectomy

“…We calculated the percent increase in EBL for every 5‐cmH 2 O increase in PEEP by using the formula (1 – 5 × exp(β)) × 100 if β < 1 and (5 × exp(β) − 1) × 100 if β > 1. Models were stratified by surgery type (RRP or RALP), and crude data were adjusted for BMI (log‐transformed), prostate weight (log‐transformed), year of surgery and surgeon, as these are factors that were previously shown to influence EBL in this population . All covariates were entered into the multivariable model.…”

“…Also, blood transfusions have been linked to cancer progression . In addition, brisk bleeding intraoperatively can obscure the surgeon's field, potentially causing the surgeon to operate more quickly, excise less tumor or inadvertently injure a nearby structure . It is important to identify potential modifiable risk factors for blood loss and attempt to minimize them.…”

“…For those patients with localized disease, RALP is a technique that offers the advantages of decreased blood loss relative to RRP . We previously investigated risk factors for EBL in RRP, and identified that higher BMI, larger prostate size, institution and more remote year of surgery all correlated with higher EBL in men undergoing RRP …”