Operating room data on 177 consecutive partial nephrectomy procedures performed by one surgeon (146 RAPN and 31 OPN) were prospectively collected over the course of 24 months (2019-2020). All RAPN procedures were completed using the Da Vinci Xi surgical system (Intuitive Surgical Company Sunnyvale, CA, USA).
Total operating room time was broken into fixed and variable time points (Figure I ). Fixed OR times were defined as in room time to anesthesia release time (IRAT), anesthesia release time to cut time (ARCT), in room time to cut time (IRCT; a combination of IRAT and ARCT), and close time to wheels out time (CTWO). Variable time was defined as surgeon operating time, cut time to close time (CTCT).
IRAT included safely delivering the patient to the operating table, safely intubating the patient, and placement of the anesthesia lines. ARCT involved correctly positioning the patient on the operating table and sterilizing the operative field. CTWO consisted of awaking the patient from anesthesia and stabilizing them prior to transport to the post-anesthesia care unit.
Evaluation of the impact procedure start time had on OR efficiency was performed by dividing procedures into morning starts (incision before 12pm) and afternoon starts (incision at or after 12pm).
For both RAPN and OPN, patients were placed in the supine position for induction of general anesthesia and line placement. Urethral catheters and orogastric tubes are placed in all patients.
Generally, two peripheral intravenous lines and an arterial line are placed.
Patients are then placed in the lateral decubitus position with the target flank placed up (Figure II A). An inflatable bean bag is used in all patients. Care is taken to cushion all pressure points including ankles, knees, hips, wrists, and elbows. The legs are separated with three pillows. The patient’s arms are placed over their head on foam pillows and secured with tape. The patient’s body is secured to the operating room table with tape.
For RAPN, pneumoperitoneum is established with the Veress needle technique. Access is gained to the abdomen with a direct visualizing port and zero-degree lens. All RAPN patients had surgery performed with four robotic arms and one 12 mm assistant port (Figures II B and II C).
For OPN, a subcostal incision was made two fingerbreadths below the costal margin for all patients. Once intra-abdominal access was achieved, an Omni-Tract retractor (Integra LifeSciences Corporation Cincinnati, OH, USA) was placed (Figure II D).
Box plots were used to graphically display the distributions of fixed and variable OR time points separately for RAPN and OPN procedures. The median and interquartile range (IQR) were used to descriptively summarize fixed and variable OR times. The Wilcoxon rank sum test was used to compare fixed OR times between procedure types (RAPN vs. OPN). The Wilcoxon rank sum test was also used to compare fixed and variable OR times between morning and afternoon procedures (morning vs. afternoon) separately for RAPN and OPN. Two-sided P values less than 0.05 were considered statistically significant. R version 4.0.3 (R Foundation for Statistical Computing, Vienna, Austria) was utilized for statistical analysis and creation of boxplots.