Multifactorial comparison of modified and conventional perfusion strategies in a porcine model of cardiopulmonary bypass.

BACKGROUND: Utilization of thromboresistant circuits in cardiopulmonary bypass (CPB) surgery has been controversial. However, due to the advantages associated with these types of circuits, we sought to evaluate the efficacy of use of low-dose heparin in conjunction with thromboresistant surfaces, closed perfusion system, elimination of blood-gas interface, maintenance of hematocrit to >25%, and systemic normothermia, with respect to the conventional strategy of non-thromboresistant open circuits with high-dose heparin, during 3 h of CPB in an animal model. METHODS: Using an open-chest swine model, animals were placed on CPB for 3 h with additional monitoring for 1 h post-CPB. Pigs were randomized into either a heparin-bonded circuit (HBC) group (n = 10) or a non-HBC (NHB) group (n = 10). Hemodynamic, hematologic, and biochemical parameters and multiphoton microscopy were used to compare the two groups. RESULTS: Pigs in the HBC group showed a 38.4% reduction in post-CPB blood loss in comparison with the NHB group (P = 0.0007). Additionally, compared with the HBC group, the NHB group exhibited a 32.7% post-CPB reduction in platelets (P < 0.001) and significant increases in alkaline phosphatase, aspartate aminotransferase, and creatine phosphokinase enzymes (P < 0.0202, P = 0.0015, P < 0.0001; respectively). Multiphoton imaging of the arterial filters revealed no entrapment of RBC, WBC, and platelets in the HBC group, while the filters in the NHB group were clogged by these cells. CONCLUSION: Utilization of modified perfusion strategy employing low-dose heparin and closed thromboresistant circuits is successful in ameliorating the potential adverse hematologic and pro-inflammatory elements induced with open perfusion system of non-thromboresistant circuits most commonly used in cardiac surgery.

Operative blood loss, blood transfusion, and 30-day mortality in older patients after major noncardiac surgery.

OBJECTIVE: Anemia and operative blood loss are common in the elderly, but evidence is lacking on whether intraoperative blood transfusions can reduce the risk of postoperative death. METHODS: We analyzed retrospective data from 239,286 patients 65 years of older who underwent major noncardiac surgery in 1997 to 2004 at veteran hospitals nationwide. Propensity-score matching was used to adjust for differences between patients who received intraoperative blood transfusions (9.4%) and those who did not, and data were used to determine the association between intraoperative blood transfusion and 30-day postoperative mortality. RESULTS: After propensity-score matching, intraoperative blood transfusion was associated with mortality risk reductions in patients with preoperative hematocrit levels of <24% (odds ratio: 0.60, 95% CI: 0.41-0.87), and in patients with hematocrit of 30% or greater when there is substantial (500-999 mL) blood loss (odds ratio: 0.35, 95% CI: 0.22-0.56 for hematocrit levels between 30%-35.9% and 0.78, 95% CI: 0.62-0.97 for hematocrit levels of 36% or greater). When operative blood loss was <500 mL, transfusion was not associated with mortality reductions for patients with hematocrit levels of 24% or greater, and conferred increased mortality risks in patients with preoperative hematocrit levels between 30% to 35.9% (odds ratio 1.29, 95% CI: 1.04-1.60). CONCLUSIONS: Intraoperative blood transfusion is associated with a lower 30-day postoperative mortality among elderly patients undergoing major noncardiac surgery if there is substantial operative blood loss or low preoperative hematocrit levels (<24%). Transfusion is associated with increased mortality risks for those with preoperative hematocrit levels between 30% and 35.9% and <500 mL of blood loss.

Evaluation of blood components exposed to coated arterial filters in extracorporeal circuits.

BACKGROUND: Biocompatible surfaces play an important role in the inflammatory response during cardiopulmonary bypass (CBP), with the arterial filter contributing a large surface area of the circuit. Different filter-coating materials designed to improve blood-filter biocompatibility are currently used in CPB circuits. This study evaluates eight biocompatible coatings used for arterial filters and their effects on blood components during circulation. METHODS: Arterial filters were randomly assigned in eight independent heparin-bonded tubing loops and perfused by a single swine (n=8). Arterial blood was routed simultaneously, but separately, into each circuit and circulated for 30 minutes at 37 degrees C. Blood samples were drawn for CBC, ACT, and TAT III measurements at baseline, post-heparinization and post-circulation. At study completion, filters were imaged using multiphoton microscopy. RESULTS: RBC, platelet, and WBC counts, and TAT III complex were all decreased after 30 minutes of circulation; however, WBC count was the only parameter that showed statistically significant differences between the filters. Circulating WBC reduction ranged from 6% (Carmeda and Trillium) to 41% (Terumo-X-coating) with corresponding microscopic confirmation of increased WBC entrapment. CONCLUSION: All eight filter coatings altered the blood components to varying degrees. Selection of the most effective filter, in conjunction with a heparin-bonded circuit for CPB, may decrease the intraoperative foreign-surface activation of blood cells.

Development and evaluation of a novel solution, Somah, for the procurement and preservation of beating and nonbeating donor hearts for transplantation.

BACKGROUND: Injury to myocytes, endocardium, and the coronary endothelium during harvesting and storage can compromise outcomes after heart transplantation. Safeguarding of structure and function of cardiomyocytes and endothelium in donor hearts may lead to improved patient survival after transplantation. Information gained from porcine hearts stored in standard transplant solution was used to design a superior preservation solution that would optimally protect and maintain organs from beating heart and/or nonbeating heart donors during long-term storage. METHODS AND RESULTS: Multiphoton microscopy was used to image deep within cardiac biopsies and coronary artery tissue harvested from porcine hearts obtained from beating heart and nonbeating heart donors for analysis of myocyte and endothelial cell structure and function. Cell structural integrity and viability, calcium mobilization, and nitric oxide generation were determined with fluorescence viability markers, immunofluorescence, and Western blots. During hypothermic storage in standard preservation solution, Celsior, myocyte, and endothelial viability was markedly attenuated in hearts obtained from beating heart donors. In contrast, hearts from beating and nonbeating heart donors stored in the newly formulated Somah solution demonstrated an increase in high-energy phosphate levels, protection of cardiac myocyte viability, mitochondrial membrane polarization, and structural proteins. Similarly, coronary artery endothelial organization and function, calcium mobilization, and nitric oxide generation were well maintained during temporal storage in Somah. CONCLUSIONS: The Celsior preservation solution in clinical use today has led to a profound decline in cardiomyocyte and endothelial cell viability, whereas the newly designed Somah solution has safeguarded myocyte and endothelial integrity and function during organ storage. Use of Somah as a storage medium may lead to optimized graft function and long-term patient survival after transplantation.

Intraoperative myocardial acidosis as a risk for hospital readmission after cardiac surgery.

BACKGROUND: This study elucidates the relationship between intraoperative myocardial acidosis/ischemia and the risk of unplanned hospital readmissions within 30 days and 6 months after cardiac surgery. METHODS: Myocardial tissue pH (corrected to 37 degrees C: pH(37C)) was monitored in 221 patients during cardiac surgery. Regional myocardial acidosis was defined in terms of specific pH thresholds. RESULTS: Fourteen percent and 27% of the patients were readmitted within 30 days and 6 months postoperatively, respectively. The mean number of readmissions was 1.67 +/- 1.24; pH(37C) <6.85 at the end of cardiopulmonary bypass (CPB) was identified as the threshold most significantly associated with readmission. This threshold was associated with a 6-fold increased risk of readmission within 30 days and a 5-fold increased risk within 6 months. CONCLUSIONS: Persistent regional myocardial acidosis after weaning from CPB independently determines unplanned readmission rates up to 6 months postoperatively. This study underscores the importance of avoiding myocardial tissue acidosis during cardiac surgery.

Derivation and validation of a preoperative prediction rule for delirium after cardiac surgery.

BACKGROUND: Delirium is a common outcome after cardiac surgery. Delirium prediction rules identify patients at risk for delirium who may benefit from targeted prevention strategies, early identification, and treatment of underlying causes. The purpose of the present prospective study was to develop a prediction rule for delirium in a cardiac surgery cohort and to validate it in an independent cohort. METHODS AND RESULTS: Prospectively, cardiac surgery patients > or =60 years of age were enrolled in a derivation sample (n=122) and then a validation sample (n=109). Beginning on the second postoperative day, patients underwent a standardized daily delirium assessment, and delirium was diagnosed according to the confusion assessment method. Delirium occurred in 63 (52%) of the derivation cohort patients. Multivariable analysis identified 4 variables independently associated with delirium: prior stroke or transient ischemic attack, Mini Mental State Examination score, abnormal serum albumin, and the Geriatric Depression Scale. Points were assigned to each variable: Mini Mental State Examination < or =23 received 2 points, and Mini Mental State Examination score of 24 to 27 received 1 point; Geriatric Depression Scale >4, prior stroke/transient ischemic attack, and abnormal albumin received 1 point each. In the derivation sample, the cumulative incidence of delirium for point levels of 0, 1, 2, and > or =3 was 19%, 47%, 63%, and 86%, respectively (C statistic, 0.74). The corresponding incidence of delirium in the validation sample was 18%, 43%, 60%, and 87%, respectively (C statistic, 0.75). CONCLUSIONS: Delirium occurs frequently after cardiac surgery. Using 4 preoperative characteristics, clinicians can determine cardiac surgery patients' risk for delirium. Patients at higher delirium risk could be candidates for close postoperative monitoring and interventions to prevent delirium.

Saphenous vein conduits harvested by endoscopic technique exhibit structural and functional damage.

BACKGROUND: Injury to the saphenous vein endothelium during harvest impacts patency after coronary artery bypass graft surgery. Many centers are adopting endoscopic saphenous vein harvest (ESVH) instead of using the traditional open saphenous vein harvest (OSVH) technique. Our objective was to compare the effects of ESVH and OSVH on the structural and functional viability of saphenous vein endothelium using multiphoton imaging, immunofluorescence, and biochemical techniques. METHODS: Ten patients scheduled for coronary artery bypass graft surgery were prospectively identified. Each underwent ESVH for one portion and OSVH for another portion of the saphenous vein. A 1-cm segment from each portion was immediately transported to the laboratory for processing. The vessel segments were labeled with fluorescent markers to quantify cell viability (esterase activity), calcium mobilization, and generation of nitric oxide. Samples were also labeled with immunofluorescent antibodies to visualize caveolin, endothelial nitric oxide synthase, von Willebrand factor, and cadherin, and extracted to identify these proteins using Western blot techniques. All labeling, imaging, and image analysis was done in a blinded fashion. RESULTS: Esterase activity was significantly higher in the OSVH group (p < 0.0001). Similarly, calcium mobilization and nitric oxide production were significantly greater in the OSVH group (p = 0.0209, p < 0.0001, respectively). Immunofluoresence and Western blot techniques demonstrated an abnormal alteration in distribution of caveolin and endothelial nitric oxide synthase in the ESVH group. CONCLUSIONS: Our study indicates that ESVH has a detrimental effect on the saphenous vein endothelium, which may lead to decreased graft patency and worse patient outcomes.

Impact of intraoperative myocardial tissue acidosis on postoperative adverse outcomes and cost of care for patients undergoing prolonged aortic clamping during cardiopulmonary bypass.

BACKGROUND: This study examined the impact of intraoperative myocardial acidosis and adverse postoperative outcomes on the cost of cardiac surgical care. METHODS: Myocardial tissue pH corrected to 37 degrees C (pH(37C)) was measured in 162 patients with cross-clamp (XC) duration of 119 minutes or longer. Perioperative data and outcomes were collected prospectively. The Veterans Affairs cost accounting system was used to determine the cost of care in a subset of 57 patients. RESULTS: Long XC duration was associated with significantly increased acidosis and adverse postoperative outcomes. The cost of care for patients with adverse outcomes was increased by 110% (P < .0001). Patients with acidosis at the end of reperfusion had significantly (P = .0470) increased costs of care. End reperfusion of myocardial tissue pH(37C) of less than 7.0, diabetes mellitus, and body surface area were significant determinants of postoperative adverse outcomes. CONCLUSIONS: Intraoperative myocardial acidosis is a determinant of postoperative adverse outcomes and cost in cardiac surgery. Reducing XC duration and improving intraoperative myocardial protection should improve outcomes and reduce cost.

Race and surgical outcomes: it is not all black and white.

BACKGROUND: Studies using Medicare data have suggested that African American race is an independent predictor of death after major surgery. We hypothesized that the apparent adverse effect of race on surgical outcomes is due to confounding by comorbidity, not race itself. METHODS: We identified all non-Hispanic white and African American general surgery, private sector patients included in the National Surgery Quality Improvement Program (NSQIP) Patient Safety in Surgery Study (2001-2004). Patient characteristics, comorbidities, and postoperative outcomes were collected/analyzed using NSQIP methodology. Characteristics between races were compared using Student t and chi(2) tests. Odds ratios (OR) for 30-day morbidity and mortality were calculated using multivariable logistic regression. RESULTS: We identified 34,141 white and 5068 African American patients. African Americans were younger but more likely to undergo emergency surgery and present with hypertension, dyspnea, diabetes, renal failure, open wounds/infection, or advanced American Society of Anesthesiology class (all P < 0.001). African Americans underwent less complex procedures but had higher unadjusted 30-day morbidity (14.33% vs. 12.35%; P < 0.001) and mortality (2.09% vs. 1.65%; P = 0.02). After controlling for comorbidity, African American race had no independent effect on mortality (OR 0.95, (0.74-1.23)) but was associated with a higher risk of postoperative cardiac arrest (OR 2.49, (1.80-3.45)) and renal insufficiency/failure (OR 1.70 (1.32-2.18)). CONCLUSION: African American race is associated with greater comorbidity and cardiac/renal complications but is not an independent predictor of perioperative mortality after general surgery. Efforts to improve postoperative outcomes in African Americans should focus on reducing the need for emergency surgery and improving perioperative management of comorbid conditions.

Troponin I after cardiac surgery and its implications on myocardial protection, outcomes, and cost.

BACKGROUND: Myocardial acidosis during cardiac surgery and postoperative troponin I are markers of myocardial damage that have been shown to predict adverse outcomes. We investigated the relationship between troponin I and myocardial tissue pH, patient outcomes, and cost. METHODS: Data were prospectively collected on 205 cardiac surgery patients. Troponin I was sampled upon arrival to the intensive care unit (ICU) and every 6 hours thereafter for 24 hours. The lowest pH encountered during aortic cross clamp (LpH) was related to postoperative troponin I on the multivariate level. Multivariate models were constructed to predict adverse events (AE) and cost. RESULTS: LpH was an independent inverse determinant of postoperative troponin I (P = .0067). Troponin I and its interaction with LpH were multivariate predictors of AE (P = .0012; .0001;odds ratio = 6.9, 10.2, respectively). Troponin I independently predicts surgical ICU (SICU) cost (P = .0256). CONCLUSION: Postoperative troponin I elevation reflects intraoperative myocardial acidosis and damage. The strong relationship between troponin I, AE, and cost indicates the damage incurred is clinically and economically relevant. Strategies to ameliorate intraoperative myocardial tissue acidosis will decrease troponin I release, subsequent AE, and associated costs.

Successful implementation of the Department of Veterans Affairs' National Surgical Quality Improvement Program in the private sector: the Patient Safety in Surgery study.

BACKGROUND: The Veterans Affairs' (VA) National Surgical Quality Improvement Program (NSQIP) has been associated with significant reductions in postoperative morbidity and mortality. We sought to determine if NSQIP methods and risk models were applicable to private sector (PS) hospitals and if implementation of the NSQIP in the PS would be associated with reductions in adverse postoperative outcomes. METHODS: Data from patients (n = 184,843) undergoing major general or vascular surgery between October 1, 2001, and September 30, 2004, in 128 VA hospitals and 14 academic PS hospitals were used to develop prediction models based on VA patients only, PS patients only, and VA plus PS patients using logistic regression modeling, with measures of patient-related risk as the independent variables and 30-day postoperative morbidity or mortality as the dependent variable. RESULTS: Nine of the top 10 predictors of postoperative mortality and 7 of the top 10 for postoperative morbidity were the same in the VA and PS models. The ratios of observed to expected mortality and morbidity in the PS hospitals based on a model using PS data only versus VA + PS data were nearly identical (correlation coefficient = 0.98). Outlier status of PS hospitals was concordant in 26 of 28 comparisons. Implementation of the NSQIP in PS hospitals was associated with statistically significant reductions in overall postoperative morbidity (8.7%, P = 0.002), surgical site infections (9.1%, P = 0.02), and renal complications (23.7%, P = 0.004). CONCLUSIONS: The VA NSQIP methods and risk models in general and vascular surgery were fully applicable to PS hospitals. Thirty-day postoperative morbidity in PS hospitals was reduced with the implementation of the NSQIP.

Impact of body mass index on perioperative outcomes in patients undergoing major intra-abdominal cancer surgery.

BACKGROUND: Obesity is an increasingly common serious chronic health condition. We sought to determine the impact of body mass index (BMI) on perioperative outcomes in patients undergoing major intra-abdominal cancer surgery. METHODS: A prospective, multi-institutional, risk-adjusted cohort study of patients undergoing major intra-abdominal cancer surgery was performed from the 14 university hospitals participating in the Patient Safety in Surgery Study of the National Surgical Quality Improvement Program (NSQIP). Demographic, clinical, and intraoperative variables and 30-day morbidity and mortality were prospectively collected in standardized fashion. Analysis of variance, Bonferroni multiple comparisons of means tests, and multivariable logistic regression analysis were performed. RESULTS: We identified 2258 patients who underwent esophagectomy (n = 29), gastrectomy (n = 223), hepatectomy (n = 554), pancreatectomy (n = 699), or low anterior resection/proctectomy (n = 753). Patients were stratified by National Institutes of Health (NIH)-defined BMI obesity class, with 573 (25.4%) patients classified as obese (BMI > 30 kg/m(2)). There were no differences in mean work relative value units, total time of operation, or length of stay amongst the BMI classes. After adjusting for other risk factors, obesity was not a risk factor for death or major complications but was a risk factor for wound complications. The risk of postoperative death was greatest in underweight patients (odds ratio [OR] 5.24; 95% confidence interval [CI] 1.7-16.2). CONCLUSION: In patients undergoing major intra-abdominal cancer surgery, obesity is not a risk factor for postoperative mortality or major complications. Importantly, underweight patients have a fivefold increased risk of postoperative mortality, perhaps a consequence of their underlying nutritional status.

Patient risk factors, operative care, and outcomes among older community-dwelling male veterans with hip fracture.

BACKGROUND: Although more than 1200 hip fracture repairs are performed in United States Department of Veterans Affairs hospitals annually, little is known about the relationship between perioperative care and short-term outcomes for veterans with hip fracture. The purpose of the present study was to test whether perioperative care impacts thirty-day outcomes, with patient characteristics being taken into account. METHODS: A national sample of 5683 community-dwelling male veterans with an age of sixty-five years or older who had been hospitalized for the operative treatment of a hip fracture at one of 108 Veterans Administration hospitals between 1998 and 2003 was identified from the National Surgical Quality Improvement Program data set. Operative care characteristics were assessed in relation to thirty-day outcomes (mortality, complications, and readmission to a Veterans Administration facility for inpatient care). RESULTS: A surgical delay of four days or more after admission was associated with a higher adjusted mortality risk (odds ratio, 1.29; 95% confidence interval, 1.02 to 1.61) but a reduced risk of readmission (odds ratio, 0.70; 95% confidence interval, 0.54 to 0.91). Compared with spinal or epidural anesthesia, general anesthesia was related to a significantly higher risk of both mortality (odds ratio, 1.27; 95% confidence interval, 1.01 to 1.55) and complications (odds ratio, 1.33; 95% confidence interval, 1.15 to 1.53). The type of procedure was not significantly associated with outcome after controlling for other variables in the model. However, a higher American Society of Anesthesiologists Physical Status Classification (ASA class) was associated with worse thirty-day outcomes. CONCLUSIONS: In addition to recognizing the importance of patient-related factors, we identified operative factors that were related to thirty-day surgical outcomes. It will be important to investigate whether modifying operative factors, such as reducing surgical delays to less than four days, can directly improve the outcomes of hip fracture repair.

Surgical site infection prevention: the importance of operative duration and blood transfusion--results of the first American College of Surgeons-National Surgical Quality Improvement Program Best Practices Initiative.

BACKGROUND: Surgical site infections (SSI) continue to be a significant problem in surgery. The American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) Best Practices Initiative compared process and structural characteristics among 117 private sector hospitals in an effort to define best practices aimed at preventing SSI. STUDY DESIGN: Using standard NSQIP methodologies, we identified 20 low outlier and 13 high outlier hospitals for SSI using data from the ACS-NSQIP in 2006. Each hospital was administered a process of care survey, and site visits were conducted to five hospitals. Comparisons between the low and high outlier hospitals were made with regard to patient characteristics, operative variables, structural variables, and processes of care. RESULT: Hospitals that were high outliers for SSI had higher trainee-to-bed ratios (0.61 versus 0.25, p < 0.0001), and the operations took significantly longer (128.3+/-104.3 minutes versus 102.7+/-83.9 minutes, p < 0.001). Patients operated on at low outlier hospitals were less likely to present to the operating room anemic (4.9% versus 9.7%, p=0.007) or to receive a transfusion (5.1% versus 8.0%, p=0.03). In general, perioperative policies and practices were very similar between the low and high outlier hospitals, although low outlier hospitals were readily identified by site visitors. Overall, low outlier hospitals were smaller, efficient in the delivery of care, and experienced little operative staff turnover. CONCLUSIONS: Our findings suggest that evidence-based SSI prevention practices do not easily distinguish well from poorly performing hospitals. But structural and process of care characteristics of hospitals were found to have a significant association with good results.

Risk-adjusted morbidity in teaching hospitals correlates with reported levels of communication and collaboration on surgical teams but not with scale measures of teamwork climate, safety climate, or working conditions.

BACKGROUND: Since the Institute of Medicine patient safety reports, a number of survey-based measures of organizational climate safety factors (OCSFs) have been developed. The goal of this study was to measure the impact of OCSFs on risk-adjusted surgical morbidity and mortality. STUDY DESIGN: Surveys were administered to staff on general/vascular surgery services during a year. Surveys included multiitem scales measuring OCSFs. Additionally, perceived levels of communication and collaboration with coworkers were assessed. The National Surgical Quality Improvement Program was used to assess risk-adjusted morbidity and mortality. Correlations between outcomes and OCSFs were calculated and between outcomes and communication/collaboration with attending and resident doctors, nurses, and other providers. RESULTS: Fifty-two sites participated in the survey: 44 Veterans Affairs and 8 academic medical centers. A total of 6,083 surveys were returned, for a response rate of 52%. The OCSF measures of teamwork climate, safety climate, working conditions, recognition of stress effects, job satisfaction, and burnout demonstrated internal validity but did not correlate with risk-adjusted outcomes. Reported levels of communication/collaboration with attending and resident doctors correlated with risk-adjusted morbidity. CONCLUSIONS: Survey-based teamwork, safety climate, and working conditions scales are not confirmed to measure organizational factors that influence risk-adjusted surgical outcomes. Reported communication/collaboration with attending and resident doctors on surgical services influenced patient morbidity. This suggests the importance of doctors' coordination and decision-making roles on surgical teams in providing high-quality and safe care. We propose risk-adjusted morbidity as an effective measure of surgical patient safety.

Mortality after nonemergent major surgery performed on Friday versus Monday through Wednesday.

OBJECTIVE: To determine whether nonemergent major surgery leads to higher mortality when performed on Friday versus early weekdays. SUMMARY BACKGROUND DATA: Adults admitted emergently to acute-care hospitals on weekends experience higher mortality than those admitted on weekdays. METHODS: Cohort study of 188,212 patients undergoing nonemergent major surgery at 124 Veterans Affairs hospitals from 2000 to 2004. Risk-adjusted 30-day mortality was compared for operations performed on Fridays versus Mondays through Wednesdays. Data were derived from the Veterans Affairs' National Surgical Quality Improvement Program database. Patients were divided into 3 groups: floor (admitted postoperatively to regular floor), ICU (admitted postoperatively to intensive care unit), and outpatient (not admitted postoperatively). A stepwise logistic regression analysis was used to test the effect of day of surgery (Friday vs. Monday-through-Wednesday) on 30-day mortality in the presence of characteristics that were significant in bivariate analysis. RESULTS: In the floor group (n = 89,786), operations performed on Fridays were associated with a higher 30-day mortality rate than those performed on Mondays through Wednesdays (2.94% vs. 2.18%; odds ratio, 1.36; 95% confidence interval, 1.24-1.49; P < 0.001). After adjusting for patient characteristics, odds ratio of 30-day mortality for operations on Fridays, when compared with Mondays through Wednesdays, was 1.17 (95% confidence interval, 1.05-1.26; P = 0.003). Within the ICU (n = 14,271) and outpatient (n = 84,155) groups, nonsignificant differences in 30-day mortality were observed for operations on Fridays versus Mondays through Wednesdays. CONCLUSIONS: For patients admitted to regular hospital floors after nonemergent major surgery, mortality is increased if surgery is performed on Friday versus Monday through Wednesday.

Detecting the blind spot: complications in the trauma registry and trauma quality improvement.

BACKGROUND: The National Surgical Quality Improvement Program (NSQIP) has reduced complications for surgery patients in the Department of Veterans Affairs Healthcare System. The American College of Surgeons Committee on Trauma maintains the National Trauma Data Bank (NTDB) to track injured patient comorbidities, complications, and mortality. We sought to apply the NSQIP methodology to collect comorbidity and outcome data for trauma patients. Data were compared to the NTDB to determine the benefit and validity of using the NSQIP methodology for trauma. STUDY DESIGN: Utilizing the NSQIP methodology, data were collected from August 1, 2004 to July 31, 2005 on all adult patients admitted to the trauma service at a level 1 trauma center. NSQIP data were collected for general surgery patients during the same time period from the same institution. Data were also extracted from v5.0 of the NTDB for patients >or=18 years old admitted to level 1 trauma centers. Comparisons between University of Michigan (UM) NSQIP Trauma and UM NSQIP General Surgery patients and between UM NSQIP Trauma and NTDB (2004) patients were performed using univariate and multivariate analysis. RESULTS: Before risk adjustment, there was a difference in mortality between the UM NSQIP Trauma and NTDB (2004) groups with univariate analysis (8.4% vs 5.7%; odds ratio [OR], 0.7; 95% confidence interval [CI] 0.5-0.9; P = .01). This survival advantage reversed to favor the UM NSQIP Trauma patient group when risk adjustment was performed (OR, 2.3; 95% CI, 1.6-3.4; P < .001). The UM NSQIP Trauma group had more complications than the UM NSQIP general surgery patients. Despite having a lower risk-adjusted rate of mortality, the UM NSQIP Trauma patients had significantly higher rates of complications (wound infection, wound disruption, pneumonia, urinary tract infection, deep vein thrombosis, and sepsis) than the NTDB (2004) patients in both univariate and multivariate analyses. CONCLUSION: Complications occurred more frequently in trauma patients than general surgery patients. The UM NSQIP Trauma patients had higher rates of complications than reported in the NTDB. The NTDB data potentially underreport important comorbidity and outcome data. Application of the NSQIP methodology to trauma may present an improved means of effectively tracking and reducing adverse outcomes in a risk-adjusted manner.

Seasonal variation in surgical outcomes as measured by the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP).

OBJECTIVE: We hypothesize that the systems of care within academic medical centers are sufficiently disrupted with the beginning of a new academic year to affect patient outcomes. METHODS: This observational multiinstitutional cohort study was conducted by analysis of the National Surgical Quality Improvement Program-Patient Safety in Surgery Study database. The 30-day morbidity and mortality rates were compared between 2 periods of care: (early group: July 1 to August 30) and late group (April 15 to June 15). Patient baseline characteristics were first compared between the early and late periods. A prediction model was then constructed, via stepwise logistic regression model with a significance level for entry and a significance level for selection of 0.05. RESULTS: There was 18% higher risk of postoperative morbidity in the early (n = 9941) versus the late group (n = 10313) (OR 1.18, 95%, CI 1.07-1.29, P = 0.0005, c-index 0.794). There was a 41% higher risk for mortality in the early group compared with the late group (OR 1.41, CI 1.11-1.80, P = 0.005, c-index 0.938). No significant trends in patient risk over time were noted. CONCLUSION: Our data suggests higher rates of postsurgical morbidity and mortality related to the time of the year. Further study is needed to fully describe the etiologies of the seasonal variation in outcomes.

The patient safety in surgery study: background, study design, and patient populations.

BACKGROUND: The purpose of this article is to describe the background, design, and patient populations of the Patient Safety in Surgery Study, as a preliminary to the articles in this journal that will report the results of the Study. STUDY DESIGN: The Patient Safety in Surgery Study was a prospective cohort study. Trained nurses collected preoperative risk factors, operative variables, and 30-day postoperative mortality and morbidity outcomes in patients undergoing major general and vascular operations at 128 Veterans Affairs (VA) medical centers and 14 selected university medical centers between October 1, 2001 and September 30, 2004. An Internet-based data collection system was used to input data from the different private medical centers. Semiannual feedback of observed to expected mortality and morbidity ratios was provided to the participating medical centers. RESULTS: During the 3-year study, total accrual in general surgery was 145,618 patients, including 68.5% from the VA and 31.5% from the private sector. Accrual in vascular surgery totaled 39,225 patients, including 77.8% from the VA and 22.2% from the private sector. VA patients were older and included a larger proportion of male patients and African Americans and Hispanics. The VA population included more inguinal, umbilical, and ventral hernia repairs, although the private-sector population included more thyroid and parathyroid, appendectomy, and operations for breast cancer. Preoperative comorbidities were similar in the two populations, but the rates of comorbidities were higher in the VA. American Society of Anesthesiologists classification tended to be higher in the VA. CONCLUSIONS: The National Surgical Quality Improvement Program methodology was successfully implemented in the 14 university medical centers. The data from the study provided the basis for the articles in this issue of the Journal of the American College of Surgeons.

Comparison of risk-adjusted 30-day postoperative mortality and morbidity in Department of Veterans Affairs hospitals and selected university medical centers: general surgical operations in men.

BACKGROUND: We used data from the Patient Safety in Surgery Study to compare patient populations, operative characteristics, and unadjusted and risk-adjusted 30-day postoperative mortality and morbidity between the Veterans Affairs (VA) (n = 94,098) and private (n = 18,399) sectors for general surgery operations in men. STUDY DESIGN: This is a prospective cohort study. Trained nurses collected preoperative risk factors, operative variables, and 30-day postoperative mortality and morbidity outcomes in male patients undergoing major general surgery operations at 128 VA medical centers and 14 university medical centers from October 1, 2001, to September 30, 2004. Multiple logistic regression analysis was used to identify preoperative predictors of postoperative mortality and morbidity. An indicator variable for VA versus private-sector medical center was added to the model to determine if risk-adjusted outcomes were significantly different in the two systems. RESULTS: The unadjusted 30-day mortality rate was higher in the VA compared with the private sector (2.62% versus 2.03%, p = 0.0002); unadjusted morbidity rate was lower in the VA compared with the private sector (12.24% versus 13.99%, p < 0.0001). After risk adjustment, odds ratio for mortality for the VA versus private sector was 1.23 (95% CI, 1.08-1.41). For morbidity after risk adjustment, the indicator variable for health-care system just missed statistical significance (p = 0.0585). Thirty-day postoperative mortality was comparable in the VA and private sector for very common operations but was higher in the VA for less common, more complex operations. CONCLUSIONS: In general surgery operations in men, the VA appeared to have a higher risk-adjusted mortality rate compared with the private sector, but differences in mortality ascertainment in the two sectors might account for some of this effect. The higher mortality in the VA could be the result of higher mortality in the less common, more complex operations. There is a trend toward lower risk-adjusted morbidity in the VA compared with the private sector.