The learning curve of BiZact™ tonsillectomy

To evaluate the learning curve of BiZact™ tonsillectomy amongst trainees and fellows as a further technical skill.

Prospective audit of consecutive BiZact™ tonsillectomies undertaken by a trainee and fellow at Starship Children's Hospital. Primary outcomes measured were operative time from gag open to gag closed, readmission and post tonsillectomy bleed rates. Secondary outcomes included need for bipolar rescue dissection, bipolar haemostasis including site and side, tonsil size (Brodsky grade 1-4) and depth (shallow or deep). Operative time was plotted against number of procedures performed and moving averages was used to investigate the learning curve. Generalised linear model was applied to examine the association between operation time and tonsil depth.

Mean operative time for the trainee and fellow was similar (07 min 34 s versus 07min and 37 s). We observed a trend of decreased operative time over number of procedures performed by the trainee but the learning curve was short. The fellow's initial time was lower than the trainee's and remained similar over time. No bipolar rescue dissection was required. Additional bipolar haemostasis was required 95% of the time, but the majority involved the superior pole only (87.5%, p = 0.0001). The overall operative time for shallow tonsils was shorter than for deep tonsils (06 min 31 s versus 08 min 09 s, p = 0.0066). A learning curve was evident for both shallow and deep tonsils for both surgeons combined but was steeper for deep. There were no primary bleeds and the secondary haemorrhage rate was 5.8% (3/51 cases) with no returns to theatre.

This is the first study to investigate the BiZact™ tonsillectomy learning curve. BiZact™ tonsillectomy is safe and easy to learn. We observed a clear trend of shallow tonsils being quicker to remove than deep tonsils using this technique. The secondary bleed rate of 5.8% is comparable to the previously published Starship rate of 4.7% for all tonsillectomies performed over a 10 year period. Moving averages is a useful method to assess operative learning curves during training and beyond.