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Learning curve for TVT-O procedure.

OBJECTIVE
To evaluate the learning curve in an untrained resident surgeon for the initial case series of tension-free vaginal tape obturator (TVT-O) to treat stress urinary incontinence.


METHODS
A retrospective observational study was conducted in Changhai Hospital, Shanghai, China, between March 2014 and June 2018. All consecutive women included were treated by TVT-O procedure performed by one surgeon, working under the supervision of an expert surgeon. Clinical features, estimated blood loss, operative time, postoperative hospital stay, total hospital stay, adverse events, and subjective and objective cure rates were recorded. Learning curve patterns were estimated to determine the number of cases to reach plateau using moving average method.


RESULTS
In total, 188 patients were included for analysis. Patients ranged from 39 to 91 years, with the average age of 57.5±9.7 years old. The mean operative time was 32.0 minutes (range 20-60). Operative time and blood loss decreased with the increase in the level of expertise, whereas postoperative hospital stay and total hospital stay were not influenced by the number of procedures performed. The number of cases required to reach plateau was approximately 30. Objective cure rate and subjective cure rate were achieved in 88.7% and 88.2% at 12 months, respectively. Groin pain was the most common post-operation complication, which continued to be present in 11.7% patients at 12 months after surgery.


CONCLUSIONS
TVT-O procedure showed encouraging objective and subjective outcomes and low complication rates, even at the initial stage of the learning curve. Thirty cases were required for a naïve resident surgeon to learn TVT-O procedures. However, long‑term outcome and complications caused by synthetic sling are still needed in further follow-up.