Clinical relevance of conversion rate and its evaluation in laparoscopic hysterectomy

Abstract

Study objectives: To estimate the current conversion rate in laparoscopic hysterectomy (LH); to estimate the influence of patient, procedure, and performer characteristics on conversion; and to hypothesize the extent to which conversion rate can act as a means of evaluation in LH.

Design: Prospective cohort study (Canadian Task Force classification II-2).

Setting: The study included 79 gynecologists representing 42 hospitals throughout the Netherlands. This reflects 75% of all gynecologists performing LH in the Netherlands, and 68% of all hospitals.

Patients: Data from 1534 LH procedures were collected between 2008 and 2010.

Intervention: All participants in the nationwide LapTop registration study recorded each consecutive LH they performed during 1 year.

Measurements and main results: Conversion rate and odds ratios (OR) of risk factors for conversion were calculated. Conversions were described as reactive or strategic. The literature reported a conversion rate for LH of 0% to 19% (mean, 3.5%). In our cohort, 70 LH procedures (4.6%) were converted. Using a mixed-effects logistic regression model, we estimated independent risk factors for conversion. Body mass index (BMI) (p = .002), uterus weight (p < .001), type of LH (p = .004), and age (p = .02) had a significant influence on conversion. The risk of conversion was increased at BMI >35 (OR, 6.53; p < .001), age >65 years (OR, 6.97; p = .007), and uterus weight 200 to 500 g (OR, 4.05; p < .001) and especially >500 g (OR, 30.90; p < .001). A variation that was not explained by the covariates included in our model was identified and referred to as the "surgical skills factor" (average OR, 2.79; p = .001).

Conclusion: Use of estimated risk factors (BMI, age, uterus weight, and surgical skills) provides better insight into the risk of conversion. Conversion rate can be used as a means of evaluation to ensure better outcomes of LH in future patients.