Background Creating highly efficient operating room (OR) protocols for total joint arthroplasty (TJA) is a challenging and multifactorial process. We evaluated whether spinal anesthesia in a designated block bay (BBSA) would reduce time to incision, improve first case start time and decrease conversion to general anesthesia (GA).

Methods Retrospective cohort study on the first 86 TJA cases with BBSA from April to December 2018, compared with 344 TJA cases with spinal anesthesia performed in the OR (ORSA) during the same period. All TJA cases were included if the anesthetic plan was for spinal anesthesia. Patients were excluded if circumstances delayed start time or time to incision (advanced vascular access, pacemaker interrogation, surgeon availability). Data were extracted and analyzed via a linear mixed effects model to compare time to incision, via a Wilcoxon rank-sum test to compare first case start time, and via a Fisher’s exact test to compare conversion to GA between the groups.

Results In the mixed effect model, the BBSA group time to incision was 5.37 min less than the ORSA group (p=0.018). The BBSA group had improved median first case start time (30.0 min) versus the ORSA group (40.5 min, p<0.0001). There was lower conversion to GA 2/86 (2.33%) in the BBSA group versus 36/344 (10.47%) in the ORSA group (p=0.018). No serious adverse events were noted in either group.

Conclusions BBSA had limited impact on time to incision for TJA, with a small decrease for single OR days and no improvement on OR days with two rooms. BBSA was associated with improved first case start time and decreased rate of conversion to GA. Further research is needed to identify how BBSA affects the efficiency of TJA.