Laura A. Graham

The attributable risk of smoking on surgical complications.

Objective:This study aimed to assess the attributable risk and potential benefit of smoking cessation on surgical outcomes. Summary Background Data:Risk reduction with the implementation of surgical care improvement project process measures has been the primary focus for improving surgical outcomes. Little emphasis has been placed on preoperative risk factor recognition and intervention. Methods:A retrospective cohort analysis of elective operations from 2002 to 2008 in the Veterans Affairs Surgical Quality Improvement Program for all surgical specialties was performed. Patients were stratified by current, prior, and never smokers. Adjusted risk of complication and death was calculated using multilevel, multivariable logistic regression. Results:Of 393,794 patients, 135,741 (34.5%) were current, 71,421 (18.1%) prior, and 186,632 (47.4%) never smokers. A total of 6225 pneumonias, 11,431 deep and superficial surgical-site infections, 2040 thromboembolic events, 1338 myocardial infarctions, and 4792 deaths occurred within 30 days of surgery. Compared with both never and prior smokers individually and controlled for patient and procedure risk factors, current smokers had significantly more postoperative pneumonia, surgical-site infection, and deaths (P < 0.001 for all). There was a dose-dependent increase in pulmonary complications based on pack-year exposure with greater than 20 pack years leading to a significant increase in smoking-related surgical complications. Conclusions:This is the first study to assess the risk of current versus prior smoking on surgical outcomes. Despite being younger and healthier, current smokers had more adverse perioperative events, particularly respiratory complications. Smoking cessation interventions could potentially reduce the occurrence and costs of adverse perioperative events.

Timing of Surgical Antibiotic Prophylaxis and the Risk of Surgical Site Infection

IMPORTANCE Timing of prophylactic antibiotic administration for surgical procedures is a nationally mandated and publicly reported quality metric sponsored by the Centers for Medicare and Medicaid Services Surgical Care Improvement Project. Numerous studies have failed to demonstrate that adherence to the Surgical Care Improvement Project prophylactic antibiotic timely administration measure is associated with decreased surgical site infection (SSI). OBJECTIVE; To determine whether prophylactic antibiotic timing is associated with SSI occurrence. DESIGN Retrospective cohort study using national Veterans Affairs patient-level data on prophylactic antibiotic timing for orthopedic, colorectal, vascular, and gynecologic procedures from 2005 through 2009. SETTING National Veterans Affairs Surgical Care Improvement Project data from 112 Veterans Affairs hospitals and matched Veterans Affairs Surgical Quality Improvement Program data. PATIENTS Patients undergoing hip or knee arthroplasty, colorectal surgical procedures, arterial vascular surgical procedures, and hysterectomy. INTERVENTION Timing of prophylactic antibiotic administration with respect to surgical incision time. MAIN OUTCOMES AND MEASURES Data for prophylactic antibiotic agent, prophylactic antibiotic timing with respect to surgical incision, and patient and procedure risk variables were assessed for their relationship with the occurrence of a composite superficial or deep incisional SSI within 30 days after the procedure. Nonlinear generalized additive models were used to examine the association between antibiotic timing and SSI. RESULTS Of the 32,459 operations, prophylactic antibiotics were administered at a median of 28 minutes (interquartile range, 17-39 minutes) prior to surgical incision, and 1497 cases (4.6%) developed an SSI. Compared with procedures with antibiotic administration within 60 minutes prior to incision, higher SSI rates were observed for timing more than 60 minutes prior to incision (unadjusted odds ratio [OR] = 1.34; 95% CI, 1.08-1.66) but not after incision (unadjusted OR = 1.26; 95% CI, 0.92-1.72). In unadjusted generalized additive models, we observed a significant nonlinear relationship between prophylactic antibiotic timing and SSI when considering timing as a continuous variable (P = .01). In generalized additive models adjusted for patient, procedure, and antibiotic variables, no significant association between prophylactic antibiotic timing and SSI was observed. Vancomycin hydrochloride was associated with higher SSI occurrence for orthopedic procedures (adjusted OR = 1.75; 95% CI, 1.16-2.65). Cefazolin sodium and quinolone in combination with an anaerobic agent were associated with fewer SSI events (cefazolin: adjusted OR = 0.49; 95% CI, 0.34-0.71; quinolone: adjusted OR = 0.55; 95% CI, 0.35-0.87) for colorectal procedures. CONCLUSIONS AND RELEVANCE The SSI risk varies by patient and procedure factors as well as antibiotic properties but is not significantly associated with prophylactic antibiotic timing. While adherence to the timely prophylactic antibiotic measure is not bad care, there is little evidence to suggest that it is better care.

Long-Term Follow-Up of Technical Outcomes for Incisional Hernia Repair

BACKGROUND Incisional hernia repair (IHR) is plagued by high recurrence rates and lack of long-term outcomes data to guide repair technique. Mesh repair reduces recurrence rates but lacks standardization of technique. We investigated long-term outcomes of elective IHR, focusing on technical predictors of recurrence. STUDY DESIGN This retrospective multicenter cohort study included elective IHR performed at 16 Veterans Affairs hospitals between 1997 and 2002. Hernia characteristics and operative details were abstracted from operative notes, and chart review was performed to identify recurrence and complications. Kaplan-Meier curves and Cox regression models were used to evaluate the effects of hernia characteristics and operative technique on recurrence. RESULTS There were 1,346 elective IHRs, of which 22% were recurrent hernias. Repair technique was primary suture in 31%, open inlay or onlay mesh in 30%, open underlay in 30%, and laparoscopic in 9%. At median follow-up of 73.4 months, there were 383 recurrences (28.5%), 23 mesh removals (1.7%), and 7 enterocutaneous fistulas (ECF) (0.5%). On Cox regression modeling with adjustment for hernia and Veterans Affairs site characteristics, the effectiveness of mesh varied by position. Compared with suture repair, laparoscopic (hazard ratio = 0.49; 95% CI, 0.28-0.84) and open underlay mesh repair (hazard ratio = 0.72; 95% CI, 0.53-0.98) substantially reduced the recurrence risk, but onlay or inlay mesh repair did not. Mesh position did not affect mesh removal or ECF rates. CONCLUSIONS Underlay technique, either laparoscopic or open, for mesh implantation during elective IHR substantially reduces the risk of recurrence, without increasing the risk of serious mesh infection or ECF.

Elective surgical case cancellation in the Veterans Health Administration system: identifying areas for improvement

BACKGROUND This study evaluated elective surgical case cancellation (CC) rates, reasons for these cancellations, and identified areas for improvement within the Veterans Health Administration (VA) system. METHODS CC data for 2006 were collected from the scheduling software for 123 VA facilities. Surveys were distributed to 40 facilities (10 highest and 10 lowest CC rates for high- and low-volume facilities). CC reasons were standardized and piloted at 5 facilities. RESULTS Of 329,784 cases scheduled by 9 surgical specialties, 40,988 (12.4%) were cancelled. CC reasons (9,528) were placed into 6 broad categories: patient (35%), work-up/medical condition change (28%), facility (20%), surgeon (8%), anesthesia (1%), and miscellaneous (8%). Survey results show areas for improvement at the facility level and a standardized list of 28 CC reasons was comprehensive. CONCLUSIONS Interventions that decrease cancellations caused by patient factors, inadequate work-up, and facility factors are needed to reduce overall elective surgical case cancellations.

Oral Antibiotic Bowel Preparation Significantly Reduces Surgical Site Infection Rates and Readmission Rates in Elective Colorectal Surgery.

OBJECTIVE To determine the relationship between oral antibiotic bowel preparation (OABP) and surgical site infection (SSI) rates in a national colectomy cohort. BACKGROUND OABP for elective colorectal surgery has fallen out of favor. Large cohort studies show that OABP is associated with a 50% reduction in SSI after colectomy. METHODS A retrospective analysis of the National Surgical Quality Improvement Program colectomy cohort from 2011 to 2012 was performed to examine the association between use of OABP and outcomes of SSI, length of stay (LOS), and readmission after elective colectomy. Univariate and multivariable analyses for SSI were performed. RESULTS The cohort included 8415 colorectal operations of which 5291 (62.9%) had a minimally invasive surgical (MIS) approach. Overall, 25.6% had no bowel preparation, 44.9% had mechanical bowel preparation (MBP) only, and 29.5% received OABP. The SSI rate was 11.1%, and it varied by preparation type: 14.9% no preparation, 12.0% MBP, and 6.5% OABP (P < 0.001). OABP group had significantly shorter hospital LOS: (median = 4, interquartile range: 3-6) versus other preparations (median LOS = 5) (P < 0.001). Readmission rates were lowest in OABP (8.1%) and highest in the no preparation group (11.8%). Multivariable logistic regressions found OABP associated with lower SSI [adjusted odds ratio (ORadj) = 0.46, 95% confidence interval (CI): 0.36-0.59]. Stratified models found OABP protective for SSI for both open procedures (ORadj = 0.40, 95% CI: 0.30-0.53) and MIS procedures (ORadj = 0.48, 95% CI: 0.36-0.65). CONCLUSIONS OABP is associated with reduced SSI rates, shorter LOS, and fewer readmissions. Adoption of OABP before elective colectomy would reduce SSI without effecting LOS. The practice of MBP alone should be abandoned.

HIV and hepatitis B and C incidence rates in US correctional populations and high risk groups: a systematic review and meta-analysis.

BackgroundHigh Human Immunodeficiency Virus (HIV) prevalence and high risk behaviors have been well documented within United States (US) correctional systems. However, uncertainty remains regarding the extent to which placing people in prison or jail increases their risk of HIV infection, and regarding which inmate populations experience an increased incidence of HIV. Describing these dynamics more clearly is essential to understanding how inmates and former detainees may be a source for further spread of HIV to the general US population.MethodsThe authors conducted a systematic review and meta-analysis of studies describing HIV incidence in US correctional facility residents and, for comparison, in high risk groups for HIV infection, such as non-incarcerated intravenous drug users (IVDU) and men who have sex with men (MSM) in the US. HIV incidence rates were further compared with Hepatitis B and Hepatitis C Virus rates in these same populations.ResultsThirty-six predominantly prospective cohort studies were included. Across all infection outcomes, continuously incarcerated inmates and treatment recruited IVDU showed the lowest incidence, while MSM and street recruited IVDU showed the highest. HIV incidence was highest among inmates released and re-incarcerated. Possible sources of heterogeneity identified among HIV studies were risk population and race.ConclusionsAlthough important literature gaps were found, current evidence suggests that policies and interventions for HIV prevention in correctional populations should prioritize curtailing risk of infection during the post-release period. Future research should evaluate HIV incidence rates in inmate populations, accounting for proportion of high risk sub-groups.

Risk of complications from enterotomy or unplanned bowel resection during elective hernia repair

HYPOTHESIS Enterotomy or unplanned bowel resection (EBR) may occur during elective incisional hernia repair (IHR) and significantly affects surgical outcomes and hospital resource use. DESIGN Retrospective review of patients undergoing IHR between January 1998 and December 2002. SETTING Sixteen tertiary care Veterans Affairs medical centers. PATIENTS A total of 1124 elective incisional hernia repairs identified in the National Surgical Quality Improvement Program data set. INTERVENTION Elective IHR. MAIN OUTCOME MEASURES Thirty-day postoperative complication rate, return to operating room, length of stay, and operative time. RESULTS Of the 1124 elective procedures, 74.1% were primary IHR, 13.3% were recurrent prior mesh IHR, and 12.6% were recurrent prior suture. Overall, 7.3% had an EBR. The incidence of EBR was increased in patients with prior repair: 5.3% for primary repair, 5.7% for recurrent prior suture, and 20.3% for prior mesh repair (P < .001). The occurrence of EBR was associated with increased postoperative complications (31.7% vs 9.5%; P < .001), rate of reoperation within 30 days (14.6% vs 3.6%; P < .001), and development of enterocutaneous fistula (7.3% vs 0.7%; P < .001). After adjusting for procedure type, age, and American Society of Anesthesiologists class, EBR was associated with an increase in median operative time (1.7 to 3.5 hours; P < .001) and mean length of stay (4.0 to 6.0 days; P < .001). CONCLUSIONS Enterotomy or unplanned bowel resection is more likely to complicate recurrent IHR with prior mesh. The occurrence of EBR is associated with increased postoperative complications, return to the operating room, risk of enterocutaneous fistula, length of hospitalization, and operative time.

Predictors of mesh explantation after incisional hernia repair

BACKGROUND Prosthetic mesh used for incisional hernia repair (IHR) reduces hernia recurrence. Mesh infection results in significant morbidity and challenges for subsequent abdominal wall reconstruction. The risk factors that lead to mesh explantation are not well known. METHODS This is a multisite cohort study of patients undergoing IHR at 16 Veterans Affairs hospitals from 1998 to 2002. RESULTS Of the 1,071 mesh repairs, 55 (5.1%) had subsequent mesh explantation at a median of 7.3 months (interquartile range 1.4-22.2) after IHR with permanent mesh prosthesis. Infection was the most common reason for explantation (69%). No differences were observed by the type of repair. Adjusting for covariates, same-site concomitant surgery (hazard ratio [HR] = 6.3) and postoperative surgical site infection (HR = 6.5) were associated with mesh explantation. CONCLUSIONS Patients undergoing IHR with concomitant intra-abdominal procedures have a greater than 6-fold increased hazard of subsequent mesh explantation. Permanent prosthetic mesh should be used with caution in this setting.

The Incidence and Timing of Noncardiac Surgery after Cardiac Stent Implantation

BACKGROUND In November 2007, national guidelines were released recommending delay of elective noncardiac surgery after cardiac revascularization with drug eluting stents (DES) for 12 months compared with 6 weeks after implantation of bare metal stents (BMS). STUDY DESIGN To determine the incidence of noncardiac surgery within 24 months after stent placement, national VA data on cardiac stent implantation were merged with data from the VA National Surgery Office and Medicare. Using chi-square tests and log-rank analyses, we measured the incidence of noncardiac surgery after BMS and DES in relation to guideline release and surgical characteristics. RESULTS From 2000 to 2010, 126,773 stent procedures were followed by 25,977 (20.5%) noncardiac operations within 24 months. Overall, 11.8% of the BMS surgery cohort had early surgery (less than 6 weeks) compared with 46.7% of the DES surgery cohort, which had early surgery (less than 12 months). The incidence of surgery differed significantly by stent type (BMS 24.1% vs DES 17.5%, p < 0.001) and in relation to guideline release (pre- 24.6% vs postguideline 13.1%, p < 0.001). Higher complexity operations (work relative value units) were more likely to occur in the early period for both BMS (p < 0.0001) and DES (p < 0.003). After guideline release, the incidence of surgery within 12 months decreased from 16.7% to 10.0% (p < 0.0001). CONCLUSIONS We found evidence that guidelines recommending delaying surgery appear to be effective in decreasing the incidence of early surgery; however, early surgery is still a frequent occurrence. Additional research is needed to better define the risk of cardiac and bleeding complications in patients undergoing subsequent noncardiac surgery, as well as the optimal time for surgery and method of antiplatelet management.

Effect of Mesh Type and Position on Subsequent Abdominal Operations after Incisional Hernia Repair

BACKGROUND The frequency of subsequent abdominal operations (SAO) and complications attributable to earlier ventral incisional hernia repair (VIHR) are unknown. We examined the effect of repair type and technique on the difficulty and complications of subsequent surgery. STUDY DESIGN A cohort of VIHRs at 16 Veterans Affairs hospitals between 1998 and 2002 was examined for postrepair abdominal operation by chart review. The primary independent variable was type and technique of the index VIHR: suture or mesh repair stratified by mesh type and position in relation to abdominal wall musculature. Subsequent surgery characteristics including operative time, inadvertent enterotomy, mesh removal, and length of postoperative stay were determined by chart review. Regression modeling was used to adjust for potential confounding variables. RESULTS At a median of 80 months after VIHR in 1,444 patients, 366 (25.3%) experienced SAO. Nearly two-thirds of these involved rerepair of the VIHR with or without a concomitant procedure. Mesh removal was significantly more likely in expanded polytetrafluoroethylene repairs as compared with polypropylene repairs, regardless of technique (odds ratio = 3.6; p = 0.01). On multivariable regression modeling, polypropylene underlay (p = 0.03) and inlay (p = 0.001) and absorbable/biologic mesh (p = 0.05) significantly increased operative time for SAO. Repair type, mesh type, or position had no significant effect on risk of inadvertent enterotomy during the SAO (p≥0.27). CONCLUSIONS Subsequent abdominal operations after VIHR are common. Underlay or inlay polypropylene mesh increases SAO operative time, but there was no increased risk of intestinal injury. Earlier repair with expanded polytetrafluoroethylene did not increase operative time, but there was equivalent risk for intestinal injury and increased risk for mesh removal.