Faculty Bibliography

BACKGROUND:Accurate assessment of complications is critical in analysing surgical outcomes. The post-operative morbidity index (PMI), derived from the Modified Accordion Severity Grading System and American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP), is a quantitative measure of post-operative morbidity. This study utilizes PMI to establish the complication burden for a distal pancreatectomy (DP). METHODS:From 2005-2011, nine centres contributed ACS-NSQIP complication data for 655 DPs. Each complication was assigned an Accordion severity weight ranging from 0.11 for grade 1 to 1.00 for grade 6 (death). The PMI is the sum of complication severity weights divided by the total number of patients. RESULTS:ACS-NSQIP complications occurred in 177 patients (27.0%). The non risk-adjusted PMI for DP is 0.087. Bleeding/Transfusion and Organ Space Infection were the most common complications. Frequency and burden differed across Accordion grades. While grade 4-6 complications represented only 15.4% of complication occurrences, they accounted for 30.4% of the burden. Subgroup analysis demonstrates that the PMI did not vary based on laparoscopic versus open approach or the performance of a splenectomy. DISCUSSION/CONCLUSIONS:This study uses two validated systems to quantitatively establish the morbidity of a DP. The PMI allows estimation of both the frequency and severity of complications and thus provides a more comprehensive assessment of risk.

BACKGROUND:Positron emission tomography (PET) as an adjunct to conventional imaging in the staging of pancreatic adenocarcinoma is controversial. Herein, we assess the utility of PET in identifying metastatic disease and evaluate the prognostic potential of standard uptake value (SUV). METHODS:Imaging and follow-up data for patients diagnosed with pancreatic adenocarcinoma were reviewed retrospectively. Resectability was assessed based on established criteria, and sensitivity, specificity, and accuracy of PET were compared to those of conventional imaging modalities. RESULTS:For 123 patients evaluated 2005-2011, PET and CT/MRI were concordant in 108 (88 %) cases; however, PET identified occult metastatic lesions in seven (5.6 %). False-positive PETs delayed surgery for three (8.3 %) patients. In a cohort free of metastatic disease in 78.9 % of cases, the sensitivity and specificity of PET for metastases were 89.3 and 85.1 %, respectively, compared with 62.5 and 93.5 % for CT and 61.5 and 100.0 % for MRI. Positive predictive value and negative predictive value of PET were 64.1 and 96.4 %, respectively, compared with 75.0 and 88.9 % for CT and 100.0 and 91.9 % for MRI. Average difference in maximum SUV of resectable and unresectable lesions was not statistically significant (5.65 vs. 6.5, p = 0.224) nor was maximum SUV a statistically significant predictor of survival (p = 0.18). CONCLUSION/CONCLUSIONS:PET is more sensitive in identifying metastatic lesions than CT or MRI; however, it has a lower specificity, lower positive predictive value, and in some cases, can delay definitive surgical management. Therefore, PET has limited utility as an adjunctive modality in staging of pancreatic adenocarcinoma.

BACKGROUND:Adrenal venous sampling (AVS) is used to distinguish between bilateral idiopathic hyperplasia and a functional adrenal tumor in patients with hyperaldosteronism. Successful sampling from both adrenal veins is necessary for lateralization and may require more than 1 procedure. AVS has traditionally been performed by interventional radiologists; however, our goal was to examine the outcomes when performed by a vascular surgeon. METHODS:All patients with a diagnosis of hyperaldosteronism were referred for AVS regardless of imaging findings. Cortisol and aldosterone levels were measured in blood samples from both adrenal veins. Postoperative analysis of intraoperative laboratory values before and after cosyntropin administration determined successful cannulation and sampling of each vein. RESULTS:Between 2007 and 2012, 53 patients underwent AVS by one vascular surgeon. The average age was 54 and 63% were men. Our success rate increased with experience, because during the earlier years (2007-2010) primary and secondary success rates were 58% and 68%, respectively compared with later years (2011-2012) when primary and secondary success rates were 82% and 95%, respectively (P<0.05). Results of AVS altered localization of disease compared with what had been anticipated based on preoperative imaging and thus influenced surgical decision making in 47% of cases. CONCLUSIONS:AVS is an important procedure in the work up of hyperaldosteronism to help identify and localize metabolically active tumors. It is an additional area in medicine where a vascular surgeon can lend expertise. Success with the procedure improves with experience and should be performed by high volume surgeons.

BACKGROUND:Large centralized databases are used with increasing frequency for reporting hospital-specific and nationwide trends and outcomes after various surgical procedures in order to improve quality of surgical care. American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) is a risk-adjusted, case-weighted complication tracking initiative that reports 30-day outcomes from more than 400 academic and community institutions in the US. However, the accuracy of event reporting specific to pancreatic surgery has never been examined in depth. METHODS:We retrospectively reviewed medical records of patients, the information on whose postoperative course was originally reported through ACS-NSQIP between 2006 and 2010. Preoperative characteristics, operative data, and postoperative events were recorded after review of electronic medical records including physician and nursing notes, operative room records and anesthesiologist reports. Fidelity of reported clinical events was assessed. Accuracy, sensitivity, and specificity were calculated for each variable of interest. RESULTS:Two hundred and forty-nine pancreatectomies were reviewed, including 145 (58.2 %) Whipple procedures, 19 (7.6 %) total pancreatectomies, 65 (26.1 %) distal pancreatectomies, and 15 (6.0 %) central or partial resections. Median age was 65.7, males comprised 41.5 % of the group, and 74.3 % of patients were Caucasian. The overall rate of complications reported by NSQIP was 44.0 %, compared with 45.0 % in our review, however discordance was observed in 27.3 % of the time, including 34 cases of reporting a complication where there was not one, and 34 cases of missed complication. The most frequently reported event was postoperative bleeding requiring transfusion, however this was also the event most commonly misclassified. Additionally, three procedures unrelated to the index operation were recorded as reoperation events. While a pancreas-specific module does not yet exist, ACS-NSQIP reports a 7.6 % rate of organ-space surgical site infections; when compared with our institutional rate of Grades B and C postoperative fistula (10.4 %), we observed discordance 4.4 % of the time. Delayed gastric emptying, a common post-pancreatectomy morbidity, was not captured at all. Additionally, there were significant inaccuracies in reporting urinary tract infections, postoperative pneumonia, wound complications, and postoperative sepsis, with discordance rates of 4.4, 3.2, 3.6, and 6.8 %, respectively. CONCLUSIONS:ACS-NSQIP data are an important and valuable tool for evaluating quality of surgical care, however pancreatectomy-specific postoperative events are often misclassified, underscoring the need for a hepatopancreatobiliary-specific module to better capture key outcomes in this complex and unique patient population.

BACKGROUND:Neoadjuvant therapy and vascular resection may offer patients with locally advanced pancreatic cancer potential cure. METHODS:We reviewed medical records of patients with ductal adenocarcinoma who underwent pancreaticoduodenectomy (PD) from 1992 through 2011. We identified patients who received neoadjuvant therapy (NA+) or required vascular resection (VR+) for locally advanced disease and compared outcomes to those who did not. RESULTS:Of the 643 patients who were initially explored, 506 (143 NA+ and 363 NA- patients) ultimately underwent PD. There were no significant differences in R0 resection or morbidity. Mortality was higher in the NA+ versus NA- group (7.0 vs 3.0 %, p = 0.04). More NA+ patients underwent PD VR+ (p < 0.001). Among VR+ patients, neoadjuvant therapy resulted in significantly lower R1 resection. Among resected patients, survival of NA+ patients was significantly longer than both NA- patients (27.3 vs 19.7 months, p < 0.05) and patients abandoned because of locally advanced disease. Age, tumor grade, lymph node ratio, and R1 resection were independent predictors of poor survival. CONCLUSIONS:Neoadjuvant therapy and vascular resection offer patients with locally advanced pancreatic cancer the chance for cure with acceptable morbidity and mortality. These patients have improved survival over patients deemed locally inoperable by traditional criteria.

BACKGROUND:Race and insurance status are seen as potential barriers to health care access and maintenance. Our goal was to see how these, as well as other patient and procedural characteristics, affected our populations' upper extremity vascular access outcomes. METHODS:We retrospectively reviewed 601 vascular access patients from 2004 through 2012 in our urban university hospital. We recorded patient demographics, insurance status, comorbidities, and complications. Primary outcomes were reintervention, long-term mortality, and transplantation. RESULTS:Median age was 62 ± 15.8 years, and 58% were male. Most operations were arteriovenous fistulas (66%). The majority of patients identified themselves as Hispanic (50%), followed by white (22%), and black (19%). Most patients had Medicare only (42%), 31% had private insurance, and 27% had Medicaid as their insurance. Black/African American patients were more likely to receive an arteriovenous graft (AVG) compared with white and Hispanic patients (44% vs. 28% and 33%, P < 0.05). White patients were significantly older (68) than Hispanics (61) or blacks (58). Freedom from reintervention at 5 years was 55% with previous tunneled catheter use predictive. Mortality at 5 years was 35% and predicted by age, AVG placement, white race, and not receiving a kidney transplant. Predictors of not receiving a transplant included older age, lower albumin, AVG placement, and coronary artery disease. CONCLUSIONS:There were no disparities with insurance status in long-term outcomes in our population. Race was not a factor for reintervention or transplantation; however, black/African American patients were more likely have an AVG placed, and white patients had a lower long-term survival after access placement.

BACKGROUND:Laparoscopic retroperitoneal (RP) adrenalectomy has gained popularity as the preferred approach over transabdominal (TA) method; however, surgeons have been reluctant to offer this operation to obese patients because of the concerns over inadequate working space and overall perceived higher rate of complications. The aim of the present study was to evaluate the feasibility and safety of RP adrenalectomy compared with TA adrenalectomy, specifically in morbidly obese patients. METHODS:All laparoscopic adrenalectomies performed at our institution between 2004 and 2012 were reviewed retrospectively. Presenting features, operative characteristics, and postoperative outcomes were evaluated. Complications were graded using Clavien system. Continuous variables were compared using Student t-test. Categorical variables were compared using χ(2)-test. Prediction models were constructed using linear or logistic regression as appropriate. RESULTS:Eighty-one RP and 130 TA procedures were performed, 26 (12.3%) and 60 (28.4%), respectively in obese patients (BMI > 30). Among the obese patients, operative time and estimated blood loss were less for RP (90 versus 130 min; P < 0.001 and 0 versus 50 mL; P < 0.001). Differences in the length of stay, overall mortality, incidence and severity of postoperative complications, and rates of readmission were not statistically significant between RP and TA procedures for all comers and in the obese patients. Controlling the operative characteristics and patient-specific factors, neither operative approach nor obesity was found to independently predict the postoperative complications. CONCLUSIONS:Laparoscopic RP adrenalectomy is a safe and feasible technique for obese patients. In the obese patients and for all comers, it offers shorter operative time, decreased estimated blood loss, with comparable length of stay and morbidity and mortality rates. We therefore recommend that this technique should be considered for patients undergoing adrenal resection.