Determinants of outcomes in pancreatic surgery and use of hospital resources

Predictive Power of the NSQIP Risk Calculator for Early Post-Operative Outcomes After Whipple: Experience from a Regional Center in Northern Ontario

BACKGROUND

NSQIP Risk Calculator was developed to allow surgeons to inform their patients about their individual risks for surgery. Its ability to predict complication rates and length of stay (LOS) has made it an appealing tool for both patients and surgeons. However, the NSQIP Risk Calculator has been criticized for its generality and lack of detail towards surgical subspecialties, including the hepatopancreaticobiliary (HPB) surgery. We wish to determine whether the NSQIP Risk Calculator is predictive of post-operative complications and LOS with respect to Whipple's resections for our patient population. As well, we wish to identify strategies to optimize early surgical outcomes in patients with pancreatic cancer.

METHODS

We conducted a retrospective review of patients who underwent elective Whipple's procedure for benign or malignant pancreatic head lesions at Health Sciences North (Sudbury, Ontario), a tertiary care center, from February 2014 to August 2016. Comparisons of LOS and post-operative complications between NSQIP-predicted and actual ones were carried out. NSQIP-predicted complications rates were obtained using the NSQIP Risk Calculator through pre-defined preoperative risk factors. Clinical outcomes examined, at 30 days post-operation, included pneumonia, cardiac events, surgical site infection (SSI), urinary tract infection (UTI), venous thromboembolism (VTE), renal failure, readmission, and reoperation for procedural complications. As well, mortality, disposition to nursing or rehabilitation facilities, and LOS were assessed.

RESULTS

A total of 40 patients underwent Whipple's procedure at our center from February 2014 to August 2016. The average age was 68 (50-85), and there were 22 males and 18 females. The majority of patients had independent baseline functional status (39/40) with minimal pre-operative comorbidities. The overall post-operative morbidity was 47.5% (19/40). The rate of serious complication was 17.5% with four Clavien grade II, two grade III, and one grade V complications. One mortality occurred within 30 days after surgery. NSQIP Risk Calculator was predictive for the majority of post-surgical complication types, including pneumonia, SSI, VTE, reoperation, readmission, and disposition to rehabilitation or nursing home. Our center appears to have a higher rate of UTI than NSQIP predicted (O/E = 3.9), as well, the rate of cardiac complication (O/E = 3.1) also appears to be higher at our center. With respect to readmission rates (O/E = 0.6) and renal failure (O/E = 0), NSQIP provided overestimated rates. The average LOS was 11.9 ± 0.9 days, which was not significantly different from the average LOS of 11.5 ± 0.3 days predicted by NSQIP (p = 0.3). Overall, 80% of discharges occurred less than or within 3 days of that predicted by NSQIP.

CONCLUSION

NSQIP Risk Calculator is predictive of post-operative complications and LOS for patients who have undergone Whipple's at our center. A more HPB-focused NSQIP calculator may accurately project post-operative complication in the pre-operative period. Nevertheless, the generic NSQIP has allowed us to examine our existing practice of post-operative care and has paved way to reduce cardiac and urinary complications in the future.

Health economic implications of complications associated with pancreaticoduodenectomy at a University Hospital: a retrospective cohort cost study

BACKGROUND

A cost analyses of complications following pancreaticoduodenectomy (PD) was performed in a high volume hepato-biliary-pancreatic service. We hypothesised that costs are increased with both severity and number of complications; we investigated the relationship between complications and specific cost centres.

METHODS

100 patients from 2011 to 2016 were included. Data relating to their perioperative course were collected. Complications were documented by the Clavien-Dindo classification and costs were inflated and converted to 2017 USD.

RESULTS

Mean hospital costs in complicated patients more than doubled those of uncomplicated patients ($28 330 vs. $57 150, p < 0.0001). Total hospital costs significantly increased with both severity and number of complications. This cost increase was influenced by medical consult, pathology, pharmacy, radiology, ward, intensive care, and allied health costs, but not operating theatre or anaesthesia costs. Postoperative pancreatic fistula, postoperative haemorrhage, delayed gastric emptying and infection were associated with cost differentials of $65 438, $74 079, $35 620 and $46 316 respectively over uncomplicated patients.

CONCLUSION

The development of complications following PD is common, costly and associated with increased length of stay. Costs increased with greater complication severity, and specific complications. The in-depth breakdown of hospital costs suggests specific targets for cost containment.

Risk factors of liver metastasis from advanced pancreatic adenocarcinoma: a large multicenter cohort study

BACKGROUND

Clinical prognostic parameters of liver metastasis from pancreatic adenocarcinoma have not been specifically identified.This study is to explore the risk factors of liver metastasis in advanced pancreatic adenocarcinoma (PDAC) patients in China.

METHODS

A multicenter cohort study was conducted to explore whether liver metastasis in locally advanced and metastatic PDAC could be reflected by some common laboratory indexes. We collected 1787 advanced PDAC patients from three participating hospitals between 2004 and 2014. The associations between some laboratory indexes and risks of liver metastases were analyzed.

RESULTS

Results have shown that 87% of stage IV patients developed synchronous liver metastasis. Primary tumor location (body/tail vs. head/neck, OR 0.55, 95% CI 0.36-0.83), primary tumor diameter (≥20 mm vs. <20 mm, OR 1.77, 95% CI 1.16-2.70), elevated ALT and AST (OR 1.62, 95% CI 0.92-2.83), and elevated CA19-9 (OR 2.72, 95% CI 1.85-3.99) upon diagnosis are significantly associated with risk of synchronous liver metastasis. Among stage III patients, 30.1% developed metachronous liver metastasis. However, no risk factors were identified among these patients.

CONCLUSIONS

Primary tumor location, diameter, elevated ALT and AST, and increased CA19-9 are independent risk factors of synchronous liver metastasis in PDAC patients.

Risk by indication for pancreaticoduodenectomy in patients 80 years and older: a study from the American College of Surgeons National Surgical Quality Improvement Program

BACKGROUND

Expected mortality after elective pancreaticoduodenectomy (PD) in contemporary series is less than 5% in elderly patients; however, to our knowledge, mortality rate has not been correlated with indication for PD. We hypothesized that perioperative risk following PD would correlate with diagnostic indication in older patients.

METHODS

The American College of Surgeons NSQIP database was reviewed to identify patients (<80 and ≥80 years) who underwent PD from January 1, 2005, through December 31, 2012. High- and low-risk diagnoses were determined by using 30-day, major-morbidity data. Univariate and multivariable analyses were used to compare outcomes.

RESULTS

Pancreatic cancer and chronic pancreatitis were found to be low-risk diagnoses in elderly patients, whereas bile duct and ampullary neoplasm, duodenal neoplasm, and neuroendocrine tumors were high-risk diagnoses. The risk of 30-day mortality for older patients (≥80 y) undergoing PD was 6.1% for those with high-risk diagnoses vs 4.5% for those with low-risk diagnoses (P = .27). On multivariable analysis (controlling for confounders), a high-risk diagnosis was shown to be an independent predictor of prolonged length of stay, superficial surgical-site infection (SSI), and organ-space SSI. There was no increased risk of complications in patients ≥80 years with low-risk diagnoses.

CONCLUSION

In patients 80 or older undergoing PD, perioperative risk varies by diagnostic indication. Patients should receive preoperative counseling about their risk.

The Effect of Body Mass Index on Surgical Outcomes in Patients Undergoing Pancreatic Resection: A Systematic Review and Meta-Analysis

OBJECTIVES

Previous studies that investigated the association between body mass index (BMI) and pancreatectomy outcomes have produced conflicting conclusions. We conducted this meta-analysis to assess the association between them.

METHODS

We searched PubMed, EMBASE, and Cochrane Library databases up to December 28, 2014. Patients were divided into high-BMI group (BMI ≥ 25 kg/m) and normal-BMI group (BMI < 25 kg/m). Postoperative and intraoperative outcomes were evaluated. Meta-regression and subgroup analysis were performed to evaluate any factors accountable for the heterogeneity. Meta-analysis was performed using a random-effect model.

RESULTS

We included 22 studies involving 8994 patients. Patients in the high-BMI group had significantly increased postoperative pancreatic fistula rate (odds ratio [OR],1.96; 95% confidence interval [CI], 1.43-2.67), delayed gastric emptying rate (OR, 1.62; 95% CI, 1.15-2.29), wound infection rate (OR, 1.43; 95% CI, 1.07-1.93), operation time (mean difference [MD],15; 95% CI, 13.40-16.60), blood loss (MD, 270.71; 95% CI, 248.93-292.49), and length of hospital stay (MD, 2.87; 95% CI, 1.51-4.24). For modest heterogeneity in postoperative pancreatic fistula, regional distribution tended to be the contributor.

CONCLUSIONS

High BMI not only increased the surgical difficulty but also decreased the surgical safety for pancreatectomy.

Management of borderline resectable pancreatic cancer

Pancreatic cancer is the fourth most common cause of cancer death in the United States. Surgery remains the only curative option; however only 20% of the patients have resectable disease at the time of initial presentation. The definition of borderline resectable pancreatic cancer is not uniform but generally denotes to regional vessel involvement that makes it unlikely to have negative surgical margins. The accurate staging of pancreatic cancer requires triple phase computed tomography or magnetic resonance imaging of the pancreas. Management of patients with borderline resectable pancreatic cancer remains unclear. The data for treatment of these patients is primarily derived from retrospective single institution experience. The prospective trials have been plagued by small numbers and poor accrual. Neoadjuvant therapy is recommended and typically consists of chemotherapy and radiation therapy. The chemotherapeutic regimens continue to evolve along with type and dose of radiation therapy. Gemcitabine or 5-fluorouracil based chemotherapeutic combinations are administered. The type and dose of radiation vary among different institutions. With neoadjuvant treatment, approximately 50% of the patients are able to undergo surgical resections with negative margins obtained in greater than 80% of the patients. Newer trials are attempting to standardize the definition of borderline resectable pancreatic cancer and treatment regimens. In this review, we outline the definition, imaging requirements and management of patients with borderline resectable pancreatic cancer.

Identification of risk categories for in pancreaticoduodenectomy based on diagnosis

BACKGROUND

Studies of pancreaticoduodenectomy (PD) frequently overlook diagnosis as a variable when evaluating postoperative outcomes or generically group patients according to whether they have 'benign' or 'malignant' disease. Large multicentre studies comparing postoperative outcomes in PD stratified by diagnosis are lacking. The present study was conducted to verify the hypothesis that postoperative morbidity and length of stay (LoS) following PD vary by diagnosis and that patients may be grouped into low- and high-risk categories.

METHODS

The database of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) was reviewed for all PDs performed during 2005-2011. Diagnoses were identified using ICD-9 codes and grouped based on the incidence of major morbidity. Univariate and multivariate analyses were utilized to assess the impact of diagnosis on PD outcomes.

RESULTS

Of 5537 patients, those with pancreas cancer (n = 3173) and chronic pancreatitis (n = 485) experienced similar incidences of major morbidity (P = 0.95) and were grouped as having low-risk diagnoses. Patients with bile duct and ampullary (n = 1181), duodenal (n = 558) and neuroendocrine (n = 140) disease experienced similar levels of major morbidity (P = 0.78) and were grouped as having high-risk diagnoses. A high-risk diagnosis was identified as an independent risk factor for a prolonged LoS [odds ratio (OR) 1.67], organ space infection (OR 2.57), sepsis or septic shock (OR 1.83), and major morbidity (OR 1.70). Diagnosis did not predict readmission.

CONCLUSIONS

The high-risk diagnosis is independently associated with postoperative morbidity and prolonged LoS. Patients with PD should be stratified by diagnosis to more accurately reflect their risk for postoperative complications and the complexity of care they will require.

Development and validation of a risk calculator for predicting postoperative pneumonia

OBJECTIVE

To identify preoperative factors associated with an increased risk of postoperative pneumonia and subsequently develop and validate a risk calculator.

PATIENTS AND METHODS

The American College of Surgeons' National Surgical Quality Improvement Program, a multicenter, prospective data set (2007-2008) was used. Univariate and multivariate logistic regression analyses were performed. The 2007 data set (N=211,410) served as the training set, and the 2008 data set (N=257,385) served as the validation set.

RESULTS

In the training set, 3825 patients (1.8%) experienced postoperative pneumonia. Patients who experienced postoperative pneumonia had a significantly higher 30-day mortality (17.0% vs 1.5%; P<.001). On multivariate logistic regression analysis, 7 preoperative predictors of postoperative pneumonia were identified: age, American Society of Anesthesiologists class, chronic obstructive pulmonary disease, dependent functional status, preoperative sepsis, smoking before operation, and type of operation. The risk model based on the training data set was subsequently validated on the validation data set, with model performance being very similar (C statistic: 0.860 and 0.855, respectively). The high C statistic indicates excellent predictive performance. The risk model was used to develop an interactive risk calculator.

CONCLUSION

Preoperative variables associated with an increased risk of postoperative pneumonia include age, American Society of Anesthesiologists class, chronic obstructive pulmonary disease, dependent functional status, preoperative sepsis, smoking before operation, and type of operation. The validated risk calculator provides a risk estimate for postoperative pneumonia and is anticipated to aid in surgical decision making and informed patient consent.

Underlying steatohepatitis, but not simple hepatic steatosis, increases morbidity after liver resection: a case-control study

Despite the high prevalence of fatty liver disease, the safety of liver resection in settings of steatohepatitis (SH) or hepatic steatosis is poorly understood. The aim of this study was to determine whether underlying SH or simple hepatic steatosis increases morbidity after liver resection. We compared patients undergoing liver resection with underlying SH or greater than 33% simple hepatic steatosis to controls selected for similar demographics, diagnoses, comorbidities, preoperative chemotherapy treatments, and extent of partial hepatectomy. Primary endpoints included postoperative overall and hepatic-related morbidity. One hundred and two patients with SH and 72 with greater than 33% simple hepatic steatosis who underwent liver resection from 2000 to 2011 were compared to corresponding controls. There were no differences in extent or approach of liver resection, malignant indications, preoperative chemotherapy treatment, elements of metabolic syndrome, alcohol use history, American Society of Anesthesiologists score, age, or gender between patients with SH or simple steatosis and corresponding controls. Ninety-day postoperative overall morbidity (56.9% versus 37.3%; P = 0.008), any hepatic-related morbidity (28.4% versus 15.7%; P = 0.043), surgical hepatic complications (19.6% versus 8.8%; P = 0.046), and hepatic decompensation (16.7% versus 6.9%; P = 0.049) were greater among SH patients, compared to corresponding controls. In contrast, there were no differences in postoperative overall morbidity (34.7% versus 44.4%; P = 0.310), any hepatic-related morbidity (19.4% versus 19.4%; P = 1.000), surgical hepatic complications (13.9% versus 9.7%; P = 0.606), or hepatic decompensation (8.3% versus 9.7%; P = 0.778) between simple hepatic steatosis patients and corresponding controls. Using multivariable logistic regression, SH was independently associated with postoperative overall (odds ratio [OR], 2.316; 95% confidence interval [95% CI]: 1.267-4.241; P = 0.007) and any hepatic-related (OR, 2.722; 95% CI: 1.201-6.168; P = 0.016) morbidity.

CONCLUSION

Underlying SH, but not simple hepatic steatosis, increases overall and hepatic-related morbidity after liver resection.

Obesity increases operating room time for lobectomy in the society of thoracic surgeons database

BACKGROUND

Obesity has become a major epidemic in the United States. Although research suggests obesity does not increase major morbidity or mortality after thoracic operations, it likely results in greater use of health care resources.

METHODS

We examined all patients in The Society of Thoracic Surgeons General Thoracic Surgery database with primary lung cancer who underwent lobectomy from 2006 to 2010. We investigated the impact of body mass index (BMI) on total operating room time using a linear mixed-effects regression model and multiple imputations to account for missing data. Secondary outcomes included postoperative length of stay and 30-day mortality. Covariates included age, sex, race, forced expiratory volume, smoking status, Zubrod score, prior chemotherapy or radiation, steroid use, number of comorbidities, surgical approach, hospital lobectomy volume, hospital percent obesity, and the addition of mediastinoscopy or wedge resection.

RESULTS

A total of 19,337 patients were included. The mean BMI was 27.3 kg/m2, with 4,898 patients (25.3%) having a BMI of 30 kg/m2 or greater. The mean total operating room time, length of stay, and 30-day mortality were 240 minutes, 6.7 days, and 1.8%, respectively. For every 10-unit increase in BMI, mean operating room time increased by 7.2 minutes (range, 4.8 to 8.4 minutes; p<0.0001). Higher hospital lobectomy volume and hospital percentage of obese patients did not affect the association between BMI and operative time. Body mass index was not associated with 30-day mortality or increased length of stay.

CONCLUSIONS

Increased BMI is associated with increased total operating room time, regardless of institutional experience with obese patients.

Failure to comply with NCCN guidelines for the management of pancreatic cancer compromises outcomes

INTRODUCTION

There are little data available regarding compliance with the National Comprehensive Cancer Network (NCCN) guidelines. We investigated variation in the management of pancreatic cancer (PC) among large hospitals in California, USA, specifically to evaluate whether compliance with NCCN guidelines correlates with patient outcomes.

METHODS

The California Cancer Registry was used to identify patients treated for PC from 2001 to 2006. Only hospitals with ≥ 400 beds were included to limit evaluation to centres possessing resources to provide multimodality care (n= 50). Risk-adjusted multivariable models evaluated predictors of adherence to stage-specific NCCN guidelines for PC and mortality.

RESULTS

In all, 3706 patients were treated for PC in large hospitals during the study period. Compliance with NCCN guidelines was only 34.5%. Patients were less likely to get recommended therapy with advanced age and low socioeconomic status (SES). Using multilevel analysis, controlling for patient factors (including demographics and comorbidities), hospital factors (e.g. size, academic affiliation and case volume), compliance with NCCN guidelines was associated with a reduced risk of mortality [odds ratio (OR) for death 0.64 (0.53-0.77, P < 0.0001)].

CONCLUSIONS

There is relatively poor overall compliance with the NCCN PC guidelines in California's large hospitals. Higher compliance rates are correlated with improved survival. Compliance is an important potential measure of the quality of care.

Development and validation of a risk calculator for prediction of mortality after infrainguinal bypass surgery

OBJECTIVE

For peripheral arterial disease, infrainguinal bypass grafting (BPG) carries a higher perioperative risk compared with peripheral endovascular procedures. The choice between the open and endovascular therapies is to an extent dependent on the expected periprocedural risk associated with each. Tools for estimating the periprocedural risk in patients undergoing BPG have not been reported in the literature. The objective of this study was to develop and validate a calculator to estimate the risk of perioperative mortality ≤30 days of elective BPG.

METHODS

We identified 9556 patients (63.9% men) who underwent elective BPG from the 2007 to 2009 National Surgical Quality Improvement Program data sets. Multivariable logistic regression analysis was performed to identify risk factors associated with 30-day perioperative mortality. Bootstrapping was used for internal validation. The risk factors were subsequently used to develop a risk calculator.

RESULTS

Patients had a median age of 68 years. The 30-day mortality rate was 1.8% (n = 170). Multivariable logistic regression analysis identified seven preoperative predictors of 30-day mortality: increasing age, systemic inflammatory response syndrome, chronic corticosteroid use, chronic obstructive pulmonary disease, dependent functional status, dialysis dependence, and lower extremity rest pain. Bootstrapping was used for internal validation. The model demonstrated excellent discrimination (C statistic, 0.81; bias-corrected C statistic, 0.81) and calibration. The validated risk model was used to develop an interactive risk calculator using the logistic regression equation.

CONCLUSIONS

The validated risk calculator has excellent predictive ability for 30-day mortality in a patient after an elective BPG. It is anticipated to aid in surgical decision making, informed patient consent, preoperative optimization, and consequently, risk reduction.