Risk Factors Affecting Operative Approach, Conversion, and Morbidity for Adrenalectomy: A Single Institution Series of 402 Patients

James G Bittner Iv, MD, Victoria M Gershuni, MS, Jeffrey F Moley, MD, Brent D Matthews, MD, Mary Quasebarth, RN, L Michael Brunt, MD. Sections of Minimally Invasive Surgery and Endocrine and Oncologic Surgery, Department of Surgery, Washington University School of Medicine

Introduction: Laparoscopic adrenalectomy (LA) is preferred for removal of most adrenal pathology, but risks for conversion and selection of open adrenalectomy (OA) are limited in most series due to sample size. This study aimed to investigate selection variables for OA, risk factors for conversion, and 30-day outcomes between operative approaches.
 

Methods: A prospective registry of patients who underwent adrenalectomy for any indication at a single high-volume teaching hospital from 1993 through 2010 was reviewed retrospectively. Demographic variables, perioperative data, and outcomes of patients after LA and OA were compared using nonparametric tests (α=.05). Risk factors affecting operative approach, conversion, and 30-day morbidity were determined. Data are presented as mean with standard deviation or odds ratio (OR) with 95% confidence interval.
 

Results: In total, 402 patients underwent 422 adrenalectomies. The LA (n=356) compared to OA (n=46) patients were younger (49.4±14.4 vs. 55.0±14.4 years, p=.02), had lower American Society of Anesthesiology (ASA) classification (2.5±.6 vs. 2.7±.6, p=.04), smaller preoperative tumor size (3.2±2.1 vs. 8.5±5.1 cm, p<.01), and more functional lesions (67.4% vs. 26.1%, p<.01). Most patients were female (62.1% vs. 73.9%, p=.20), had left-sided lesions (both 52%), and presented with similar body mass index (BMI) (30.3±7.5 vs. 29.0±7.4 kg/m2, p=.21). A similar proportion of LA patients had a history of prior abdominal operations (46.1% vs. 43.5%, p=.43) but fewer underwent concurrent procedures at the time of operation compared to OA patients (19% vs. 63%, p<.01). The most common operative indication for LA was pheochromocytoma (33%) and for OA was non-functioning adenoma (24%). Mean operative times for LA and OA were 159 ± 68 and 197 ± 77 minutes (p=.04). LA was associated with fewer intraoperative complications (3.4% vs. 10.9%, p=.02), less estimated blood loss (≤100 ml, 81.7% vs. 28%, p<.01), and lower transfusion requirement (2% vs. 10.9%, p<.01). Conversion occurred in 6.2% of LA patients, who remained in the LA cohort for analysis. Risks for conversion included preoperative diagnosis, need for concomitant procedures (OR 3.2, 1.3-7.9), need for transfusion (OR 24.5, 5.1-117.9), and any intraoperative complication (OR 9.1, 2.5-32.9). Hospital length of stay for LA averaged 2.5±2.2 and for OA 9.1 ± 12.1 days (p<.01). More OA patients experienced 30-day morbidity (11% vs. 23%, p<.01) but with similar severity (grade ≤2, 80% vs. 84.8%, p=.35). Variables that correlate with selection for OA are increasing patient age (p=.02), preoperative imaging size (p<.01), and ASA (p=.04), need for concomitant procedures (OR 7.2, 3.8-13.9), and non-functional lesion status (OR 5.9, 2.9-11.7). Higher BMI, prior abdominal operations, and lesion side did not impact selection for OA. Perioperative risk factors predictive of increased 30-day morbidity following adrenalectomy included use of an open approach (OR 8.1, 4.2-15.8), concomitant procedures (OR 3.8, 2.2-6.7), longer operative time, need for conversion (OR 3.5, 1.4-8.6), and pathology type.
 

Conclusions: The nature of underlying adrenal pathology and need for concurrent procedures significantly impact the selection of patients for OA, the likelihood of conversion from LA to OA, and perioperative morbidity. These metrics should be considered when assessing operative approach and risks for adrenalectomy.