Laparoendoscopic single-site upper urinary tract surgery: assessment of postoperative complications and analysis of risk factors

BACKGROUND: Laparoendoscopic single-site surgery (LESS) has been developed in an attempt to minimise the morbidity and scarring associated with surgical intervention. OBJECTIVE: To evaluate the incidence of and the risk factors for complications in patients undergoing LESS upper urinary tract surgery. DESIGN, SETTING, AND PARTICIPANTS: Between September 2007 and February 2011, 192 consecutive patients underwent LESS for upper urinary tract diseases at four institutions. MEASUREMENTS: All complications occurring at any time after surgery were captured, including the inpatient stay as well as in the outpatient setting. They were classified as early (onset<30 d), intermediate (onset 31-90 d), or late (onset>90 d) complications, depending on the date of onset. All complications were graded according to the modified Clavien classification. RESULTS AND LIMITATIONS: The patient population was generally young (mean: 55±18 yr of age), nonobese (mean body mass index [BMI]: 26.5±4.8 kg/m2), and healthy (mean preoperative American Society of Anaesthesiologists [ASA] score: 2±1). Forty-six patients had had prior abdominal surgery. Mean operative time was 164±63 min, with a mean estimated blood loss (EBL) of 147±221 ml. In 77 cases (40%), the surgeons required additional ports, with a standard laparoscopy conversion rate of 6%. Mean hospital stay was 3.3±2.3 d, and the mean visual analogue scale (VAS) score at discharge was 1.7±1.43. Thirty-three complications were recorded-30 early, 2 intermediate, and 1 late-for an overall complication rate of 17%. Statistically significant associations were noted between the occurrence of a complication and age, ASA score, EBL, length of stay (LOS), and malignant disease at pathology. Univariable and the multivariable analyses showed that a higher ASA score (incidence rate ratio [IRR]: 1.4; 95% confidence interval [CI], 1.0-2.1; p=0.034) and malignant disease at pathology (IRR: 2.5; 95% CI, 1.3-4.7; p=0.039) represented risk factors for complications. Poisson regression analysis over time showed a 23% non-statistically significant reduction in risk of complications every year (IRR: 0.77; 95% CI, 0.5-1.19; p=0.242). CONCLUSIONS: Malignant disease at pathology and high ASA score represent a predictive factor for complication after LESS for upper urinary tract surgery. Thus, surgeons approaching LESS should start with benign diseases in low-surgical-risk patients to minimise the likelihood of postoperative complications.