A practical index to predict 30-day mortality after major amputation.

BACKGROUND: Patients at risk of mortality after amputation have not been well identified. We sought to devise a clinical index predicting 30-day mortality after amputation that would allow stratification of intensity of postoperative care. METHODS: The National Surgical Quality Improvement Program (NSQIP) database (2005-2009) was analyzed for patients who had above- or below-knee amputations. An additive risk index was created based on logistic regression that examined patient demographics, comorbidities, and operative characteristics. A threshold score for clinical action was identified as the score at which the gain in certainty was maximized. The primary outcome measure was 30-day mortality. RESULTS: Among 9244 patients analyzed, there were 744 deaths (8.1%) at 30 days, with 280 occurring after hospital discharge (37.9%). The final index includes 11 components with a total score range of 0-13: age (60-79 or ≥80 years), history of congestive heart failure, chronic obstructive pulmonary disease, or major cardiac surgery, using steroid medications, having dependent functional status, dyspnea, being on dialysis, having impaired sensorium, or preoperative sepsis. This index has a c-statistic of 0.7391, and the score at which clinical action should be taken is ≥5. The observed probability of 30-day mortality increased from 1.06% at a score of 1 to 10% at 5 and 38.5% at a score of 10. CONCLUSIONS: More than one-third of deaths within 30 days of major amputation occur after discharge from acute care. A novel index to predict 30-day mortality after major amputation is described. Patients receiving a score ≥5 face a substantial risk of mortality and should be held in the hospital longer or, if discharged, receive closer postoperative follow-up.

Adoption of endovascular repair of abdominal aortic aneurysm in California: lessons for future dissemination of surgical technology.

BACKGROUND: Knowledge of the pattern of adoption of endovascular approach (endovascular aortic repair [EVAR]) to abdominal aortic aneurysm (AAA) could direct future dissemination of complex surgical technology. METHODS: Retrospective longitudinal analysis of the California Office of Statewide Health Planning and Development inpatient database from 2001 to 2008, accompanied by a cross-sectional survey of surgeons. The setting was all inpatient hospitals in California. Patients were those who underwent repair of AAA. The main outcome measure was the endovascular repair of AAA and the training experience of the surgeons. RESULTS: Of the 33,277 patients with AAA, 11,755 (35%) underwent endovascular repair; 76% were men, mean age was 73 (median, 75) years, 13% of aneurysms were ruptured, and 20% were treated at teaching hospitals. The rate of EVAR increased from 19% in 2001 to 55% in 2008. On multivariate analysis, calendar year, older age, male gender, nonruptured status, teaching hospitals, and high-volume hospitals, but not race or insurance status, were identified as independent predictors of EVAR. The survey revealed that surgeons with ≥15 years of experience obtained their training primarily from the manufacturer (58.8%), whereas those with <15 years of experience obtained their training primarily during residency or fellowship (96.7%). CONCLUSION: Between 2001 and 2008, there was a 290% increase in the rate of EVAR for AAA in California. The early adopters obtained their training directly or indirectly from the manufacturers. Training programs did not begin to offer formal training in this technology until the rapid growth was already taking place. This suggests that academic medical centers and/or professional organizations should develop plans to play a stronger and earlier role in educating physicians about a new technology.

Impact of nonresective operations for complicated peptic ulcer disease in a high-risk population.

Over the past two decades, surgery for complicated peptic ulcer disease has evolved to a "less-is-more" approach due predominately to improved medical therapy. This study sought to determine whether a nonresective operative strategy has been an effective and prudent approach. A 20-year retrospective evaluation was conducted to compare outcomes of patients from the first decade (1990-1999) with those from the more recent decade (2000-2009). In all, 50 patients underwent surgery for complications of peptic ulcer disease, 36 in the early period and 14 in the later period, with 94 per cent being urgent or emergent. Acid-reducing procedures (vagotomy) decreased significantly from 29 to 7 over the two periods (P = 0.04), as did gastric resections from 23 to 3 (P = 0.01). The prevalence of H. pylori and use of NSAIDs both increased from 28 per cent to 36 per cent and 31 per cent to 43 per cent, respectively. Postoperative mortality remained unchanged, 22 per cent vs. 7 per cent (P = 0.41) over the two periods. Resections and definitive acid-reducing procedures continue to decline with no increase in adverse outcomes. This more moderate operative approach to complicated peptic ulcer surgery is appropriate given the trend towards lower mortality and improved medical treatment. In our high-risk veteran population, overall perioperative mortality, length of stay, and reoperations have been reduced.

Prosthetic infection: lessons from treatment of the infected vascular graft.

Surgical prosthetics provide unquestioned benefit to patients in maintenance of life and limb. However, complications associated with prosthetic devices continue to represent a significant source of morbidity and mortality. Even as the surgeon becomes more adept at management of infections, the bacterial characteristics change in favor of increased virulence and greater resistance to antimicrobials. Excision or retention of the prosthesis depends on the time of presentation, the microbial isolates recovered, and the extent of surrounding tissue destruction. Recent work shows improving results with in situ replacement.

Strategies for management of ischemic steal syndrome.

Constructing vascular access for hemodialysis causes changes in blood flow to the extremity, which can lead to distal ischemia. Ischemic steal syndrome is manifested by pain; weakness; pallor; and, in severe cases, ulceration and tissue loss. Severe ischemia, requiring reintervention, has an incidence of 4%, although some degree of ischemia causing pain or parasthesias occurs in 10% to 20% of patients following access construction. Pathophysiology may be on the basis of inadequate arterial collateral inflow due to occlusive disease, particularly involving the medium-sized vessels, or high flow in a fistula exceeding the inflow capacity in the absence of intrinsic occlusive disease of the inflow arteries. Predicting steal remains difficult, although certain patient characteristics and preoperative techniques can help identify those patients in whom arteriovenous fistulas have an increased risk of causing steal. Patients with diabetes, multiple access procedures, and constructions based on proximal arteries are more prone to ischemia. Ultrasonography and digital-brachial indices measured by photoplethysmography or Doppler techniques have been used to predict fistulas that are more likely to cause ischemia, but these fall short of reliability. Operative techniques for correcting steal include arteriovenous fistula ligation, percutaneous transluminal angioplasty, banding or restrictive procedures, and distal revascularization interval ligation or modifications of this technique. Operative intervention for ischemic steal syndrome successfully resolves ischemia in 80% to 95% of patients. Some patients can have persistent pain despite healing of ulceration.

Does initial choice of antimicrobial therapy affect length of stay for patients with complicated intra-abdominal infections?

Outcomes for complicated intra-abdominal infection are influenced by operation for source control, patient-related factors, and medical management, including antibiotic treatment. We analyzed length of stay (LOS) at 33 hospitals for 2,150 patients discharged between February 2002 and June 2003, who were > 18 years, had intra-abdominal infection, and received one of 6 first-line antimicrobials. A regression tree analysis selected important variables, their interactions, and their order of significance in explaining LOS. A linear mixed model evaluated the difference in LOS between treatment groups. Adjusted LOS was calculated by the least squares means from the model and was used to assess treatment differences. Mean LOS analyzed by initial antimicrobial therapy and stratified by diagnosis showed LOS for ampicillin/sulbactam and ertapenem to be significantly shorter from levofloxacin, ceftriaxone, and piperacillin/tazobactam (all P < 0.05). Adjusting for all other factors, the variables associated with severity (e.g., diagnosis, ICU stay, and comorbidities) had the greatest impact on adjusted LOS (all P < 0.001). Our findings indicate ampicillin/sulbactam and ertapenem were associated with shorter hospital stays, which may be explained by unaccounted for underlying severity of infection and/or by surgeons stratifying antimicrobial selection according to severity of illness.

A severity score for complicated skin and soft tissue infections derived from phase III studies of linezolid.

BACKGROUND: Severity scoring systems are useful for assessing patient risk and predicting prognosis. METHODS: We developed a scoring system using data from a phase III study comparing antibiotics in hospitalized patients with complicated skin and soft tissue infections (study A), and used logistic regression analysis to identify factors contributing to treatment failure. We tested this system using data from a similar study (study B). RESULTS: In study A (n = 682), cure rates were lower in patients with at least 1 comorbid condition (P <0.05) and in the highest risk class (P = 0.05); elevated blood urea nitrogen, hyponatremia, anemia, lesion size, and surgical wound infection were independent predictors of failure (P <0.05). In study B (n = 166), findings were similar and significant for risk class (P <0.05). In the combined analysis (n = 848), cure rates were higher for linezolid than for the comparator in all patients (85% versus 77%; P <0.01) and in subanalyses by comorbid conditions, median score, and risk class (P <0.05). CONCLUSIONS: We developed and validated a scoring system in which baseline variables predicted outcome. Patients with higher severity scores generally had poorer outcomes regardless of treatment group. Our finding that linezolid was an independent predictor of cure merits further evaluation.

A consensus statement on empiric therapy for suspected gram-positive infections in surgical patients.

BACKGROUND: Multidrug resistance among gram-positive pathogens in tertiary and other care centers is common. A systematic decision pathway to help select empiric antibiotic therapy for suspected gram-positive postsurgical infections is presented. DATA SOURCES: A Medline search with regard to empiric antibiotic therapy was performed and assessed by the 15-member expert panel. Two separate panel meetings were convened and followed by a writing, editorial, and review process. CONCLUSIONS: The main goal of empiric treatment in postsurgical patients with suspected gram-positive infections is to improve clinical status. Empiric therapy should be initiated at the earliest sign of infection in all critically ill patients. The choice of therapy should flow from beta-lactams to vancomycin to parenteral linezolid or quinupristin-dalfopristin. In patients likely to be discharged, oral linezolid is an option. Antibiotic resistance is an important issue, and in developing treatment algorithms for reduction of resistance, the utility of these new antibiotics may be extended and reduce morbidity and mortality.

Prophylaxis of infection for elective colorectal surgery.

BACKGROUND: Influenced by the key results of the clinical trials conducted in the early 1970s by Condon, Nichols, and Gorbach, surgeons have adopted the routine use of mechanical bowel prep and antimicrobial prophylaxis prior to elective colorectal procedures as a widely established practice. Recent clinical trial data, however, led us to reexamine the benefits of mechanical bowel preparation, methods of antimicrobial prophylaxis and to assess the role of new, specific risk factors for surgical site infection after colorectal operations. METHODS: Pertinent studies on antimicrobial prophylaxis for elective colorectal surgery were identified from a Medline search of English language publications since 1966. RESULTS: We found credible clinical trial data that mechanical bowel preparation prior to elective colorectal surgery may not be essential. Timing of the administration of prophylactic antimicrobials is often inaccurate in current practice and suggests the need for a long-acting, broad-spectrum agent that would deemphasize precision in time of preoperative infusion. New risk factors have been identified that increase infection after colorectal surgery, including patient core temperature and tissue oxygenation. Independent observers identify postoperative surgical site infection at a higher rate than physician self-reporting and should be incorporated into future clinical trials. CONCLUSION: The once settled area of antimicrobial prophylaxis for colorectal surgery is again controversial. Cooperative clinical trials will be needed to resolve key questions such as the efficacy for bowel preparation and how to obtain effective timing of antimicrobial prophylaxis.

Telavancin, a new lipoglycopeptide antimicrobial, in complicated skin and soft tissue infections.

Telavancin, a novel lipoglycopeptide with rapid concentration-dependent bactericidal effects, is a semisynthetic derivative of the glycopeptide, vancomycin. Telavancin has a dual mechanism of action, ie, inhibition of peptidoglycan polymerization and disruption of the bacterial membrane. It has linear pharmacokinetics, rapid bactericidal killing, and broad spectrum activity against Gram positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant S. aureus. Phase II and III clinical trials for complicated skin and skin structure infections have shown telavancin to have similar efficacy and tolerability to that of vancomycin and standard anti-staphylococcal ß-lactams plus vancomycin. In Phase II trials, there was a significant difference in eradication of MRSA between groups, ie, telavancin therapy 92% and standard therapy (vancomycin, nafcillin, oxacillin, or cloxacillin) 68% (P < 0.05). In Phase III trials, among clinically evaluable patients who had MRSA isolated at baseline, the overall therapeutic response was higher in patients treated with telavancin than in patients treated with vancomycin (89.9% versus 84.7%; 95% CI -0.3, 10.5). Also, the efficacy of telavancin was not inferior to that of vancomycin for the treatment of complicated skin and skin structure infections in the clinical trials.

Glove powder increases Staphylococcus aureus abscess rate in a rat model.

BACKGROUND: Glove powder is used as a lubricant on the inner surface of many surgical gloves to aid in donning. Although surgeons routinely wash or wipe their gloves to remove the powder, studies in patients have shown that, at the conclusion of operations in which powdered gloves have been used, the wound retains a substantial amount of residual powder granules. Furthermore, the amount of residual granules is in proportion to the number of gloves that the operating room staff wear. We determined whether glove powder in combination with Staphylococcus aureus when injected into the subcutaneous tissue of the dorsum of the rat would potentiate abscess formation. METHODS: We combined methicillin-susceptible S. aureus (MSSA) in concentrations of 0, 10(2), 10(3), 10(4), and 10(5) colony forming units (cfu)/mL and starch powder in concentrations of 0, 10, 50, and 100 mg/mL and injected the inoculum into each flank of 105 Sprague-Dawley rats. Animals were euthanized 7 to 10 days after inoculation and examined for signs of abscess formation. Wounds were cultured to verify S. aureus as the causative organism. RESULTS: No abscesses formed in our control animals (sterile inoculum). Increasing concentrations of MSSA and increasing starch powder led to more-frequent abscess formation. The presence of high concentration of starch (100 mg/mL) decreased the inoculum of bacteria needed to produce an abscess from 10(4) to 10(2) cfu/mL. The presence of starch, regardless of concentration, increased the likelihood of abscess formation in the presence of bacteria (odds ratio = 1.8, 95% confidence interval = 1.06, 2.57). CONCLUSION: Surgical glove power reduces the inoculum of bacteria needed to produce an abscess and increases the likelihood of abscess formation in Sprague-Dawley rats.

Is there a current role for preoperative non-absorbable oral antimicrobial agents for prophylaxis of infection after colorectal surgery?

BACKGROUND: In numerous scientific studies, oral antibiotic bowel preparation has reduced surgical site infections in patients undergoing colorectal surgery. The historical evolution of antibiotic bowel preparation is presented with a review of the scientific basis of its effectiveness. METHODS: Review of the pertinent English language literature. RESULTS: Successful oral antibiotic bowel preparation requires effective mechanical preparation. The progressive shift of preoperative preparation to the outpatient setting has led to a reduction in the use of oral antibiotics. Such preparation, however, continues to be effective although in current surgical practice is often augmented with perioperative, parenteral antimicrobials. CONCLUSION: Oral antibiotic bowel preparation has a role in the prevention of surgical site infection in the patient undergoing colorectal surgery.

Increased endovascular interventions decrease the rate of lower limb artery bypass operations without an increase in major amputation rate.

Progression of peripheral vascular disease may lead to major amputations. We sought to understand whether more frequent endovascular angioplasty and stenting in patients with limb-threatening ischemia would affect the number of major amputations. We retrospectively reviewed the effects of implementing more frequent endovascular intervention for the 4 years 2003-2006 at the Veterans Affairs Medical Center in Long Beach, California. During this interval angioplasty became the preferred method for the treatment of infrainguinal vascular disease. Open bypass procedures were performed for patients with limb-threatening ischemia and extensive lesions that could not be treated by angioplasty. Patients were on average 68 +/- 1 years, and 96% were male. The patients were 45% active smokers, with 43% diabetics. There was 0% 30-day mortality for both groups over the 4 years. the number of below-the-knee, above-the-knee, and transmetatarsal amputations for fiscal years 2003, 2004, 2005, and 2006 were, 42, 50, 62, and 41, respectively. Concurrently, there has been a reduction in open femoral to popliteal or trifurcation vessel bypasses with 37, 43, 28, and 14 procedures for 2003, 2004, 2005, and 2006. Angioplasty and stenting increased from 12, 12, 24, to 59 over the same period. Patients who had a femoral to distal bypass were more likely to have an amputation than those undergoing angioplasty (odds ratio = 4.2, 95% confidence interval 1.6-11.5) for those with at least 1 year of follow-up, likely due to these patients having more severe disease. Increasing the frequency of angioplasty for infrainguinal vascular lesions did not increase the number of major lower extremity amputations in our stable patient population.

Definitive risk factors for anastomotic leaks in elective open colorectal resection.

HYPOTHESIS: Anastomotic leaks following elective colorectal resections increase morbidity, mortality, and the need for additional interventions. An accurate understanding of risk factors would potentially reduce anastomotic leaks and/or allow appropriate selection of patients for diverting stomas. DESIGN: Prospective review of patient and operative characteristics that contribute to anastomotic leaks. SETTING: Fifty-one sites within the United States (May 2002-March 2005). PATIENTS: Six hundred seventy-two patients who participated in a trial comparing preoperative antimicrobials in elective open colorectal surgery. MAIN OUTCOME MEASURES: Anastomotic leaks were diagnosed using clinical findings and were confirmed with imaging. We examined 20 variables possibly affecting anastomotic healing in univariate and multivariate analyses. RESULTS: There were 24 anastomotic leaks in 672 patients (3.6%) undergoing elective colorectal resection. There were 10 deaths (1.5%). A baseline albumin level of less than 3.5 g/dL (to convert to grams per liter, multiply by 10) (P = .04) and male sex (P = .03) were associated with anastomotic leaks in both univariate and multivariate analyses (adjusted odds ratios, 2.56 and 3.12, respectively). Increased duration of surgery (SD, 60 minutes; odds ratio, 1.53; 95% confidence interval, 1.06-2.22; P = .03) and steroid use at the time of surgery (odds ratio, 3.85; 95% confidence interval, 1.24-11.93; P = .02) were significant in univariate analysis. Surgical procedure with rectal resection; prophylaxis with ertapenem (vs cefotetan); or history of obesity, tobacco use, or diabetes was not associated with anastomotic leaks. CONCLUSIONS: Significant risk factors for anastomotic leaks include low preoperative serum albumin level, steroid use, male sex, and increased duration of surgery. Appreciation of risk factors provides a rational basis for temporary diversion.

Sexual dysfunction in men after open or endovascular repair of abdominal aortic aneurysms.

Few studies have thoroughly investigated the incidence and detailed the degree of sexual disability after aortic aneurysm surgery. Reports prior to 1990 vary greatly in the incidence of postoperative dysfunction mostly because of nonstandardized methods of assessment. In this article, we compare the incidence of reported sexual dysfunction after aortic reconstruction, open and endovascular abdominal aortic aneurysm repair. Pertinent studies on sexual dysfunction following open and endovascular aortic aneurysm repair were identified from a MEDLINE search of English-language publications since 1966. Newer standardized methods of assessment have identified relatively high rates of sexual dysfunction prior to and after intervention. Aortic aneurysm patients have a baseline incidence of sexual dysfunction of approximately 30%, which doubles over the next 7 years. Patients who had open aortic operations reported significantly increased sexual dysfunction during the first postoperative year. Endovascular repair with unilateral internal iliac occlusion results in new sexual dysfunction in approximately 10% of patients, but this increases significantly with bilateral internal iliac occlusion. When compared with open operation, the incidence of sexual dysfunction is lower overall in patients with endovascular aortic aneurysm repairs, which includes those who have internal iliac artery occlusion, but it is increased with bilateral iliac occlusion. Surgeons should be aware of the preoperative prevalence of sexual dysfunction in patients undergoing aortic procedures.