Risk Factors Associated With Unplanned Conversion to Open in Radical and Partial Nephrectomy.

Introduction Minimally invasive surgery (MIS), such as laparoscopic and robotic techniques, has become standard in kidney surgery due to its benefits in offering faster recovery while maintaining comparable oncologic outcomes when compared to open surgery. However, some cases still require unexpected conversion to open surgery, which can increase the risk of postoperative complications and increase the 30-day readmission risk. Predictors and risk factors for these conversions remain underexplored. This study uses the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database to identify predictors and outcomes in nephrectomy patients, therefore improving patient selection for open surgeries. Methods Using the 2019-2020 NSQIP data, this retrospective study analyzed 14,186 patients, 4,862 of whom met the inclusion criteria of nephrectomy for kidney cancer. Patients were subcategorized into planned MIS (n=4,756) and unplanned conversion to open (UCO) (n=106). The Wilcoxon signed-rank test was utilized for continuous variables, and Fisher's exact test was performed for categorical variables, including chi-squared analysis. Statistical significance was set at a P-value of <0.05. Results Unplanned conversion to open rate was 2.2%. There was an increased incidence of unplanned conversion to open in T3 and T4 tumors (30.2% and 8.5%) compared to the planned group (21.2% and 0.50%). Patients in the American Society of Anesthesiologists (ASA) classification 3 and 4 categories were more likely to be within the unplanned group. Outcomes (readmission, blood transfusion, mean operative time, the length of stay, prolonged nil per os/nasogastric tube {NPO/NGT}, and lymphocele/lymphatic leak) were compared between the groups. Conclusion Higher tumor stage, higher ASA classification, deranged kidney function, and raised prothrombin time/international normalized ratio (PT/INR) were predictive factors for unplanned conversions, with worse outcomes such as prolonged hospitalizations and postoperative complications.