Sex- and diagnosis-dependent differences in mortality and admission cytokine levels among patients admitted for intensive care.

OBJECTIVES: To investigate the role of sex on cytokine expression and mortality in critically ill patients. DESIGN: A cohort of patients admitted to were enrolled and followed over a 5-year period. SETTING: Two university-affiliated hospital surgical and trauma ICUs. PATIENTS: Patients 18 years old and older admitted for at least 48 hours to the surgical or trauma ICU. INTERVENTIONS: Observation only. MEASUREMENTS AND MAIN RESULTS: Major outcomes included admission cytokine levels, prevalence of ICU-acquired infection, and mortality during hospitalization conditioned on trauma status and sex. The final cohort included 2,291 patients (1,407 trauma and 884 nontrauma). The prevalence of ICU-acquired infection was similar for men (46.5%) and women (44.5%). All-cause in-hospital mortality was 12.7% for trauma male patient and 9.1% for trauma female patient (p = 0.065) and 22.9% for nontrauma male patients and 20.6% for nontrauma female patients (p = 0.40). Among trauma patients, logistic regression analysis identified female sex as protective for all-cause mortality (odds ratio, 0.57). Among trauma patients, men had significantly higher admission serum levels of interleukin-2, interleukin-12, interferon-γ, and tumor necrosis factor-α, and among nontrauma patients, men had higher admission levels of interleukin-8 and tumor necrosis factor-α. CONCLUSIONS: The relationship between sex and outcomes in critically ill patients is complex and depends on underlying illness. Women appear to be better adapted to survive traumatic events, while sex may be less important in other forms of critical illness. The mechanisms accounting for this gender dimorphism may, in part, involve differential cytokine responses to injury, with men expressing a more robust proinflammatory profile.

Continuous intraoperative temperature measurement and surgical site infection risk: analysis of anesthesia information system data in 1008 colorectal procedures.

OBJECTIVES: To investigate the association between intraoperative temperature and surgical site infection (SSI) in colorectal surgery with anesthesia information system data. METHODS: Continuously measured intraoperative anesthesia information system temperature data for adult abdominal colorectal surgery procedures at a large tertiary center for 1 year were linked to 30-day American College of Surgeons National Surgical Quality Improvement Program SSI outcomes. Univariable and multivariable analyses of SSI to descriptive temperature statistics, absolute and relative temperature threshold times, and other clinically relevant variables were performed. RESULTS: Overall, 1008 patients (48% female, median age: 53 years) underwent major colorectal procedures (7% emergent, 72% open, 173 ± 95 minutes mean procedure time) with median intraoperative temperature 36.0°C, using active rewarming in 92% and 1-hour presurgical antibiotic administration in 91%. Thirty-day overall and organ/space infection rates were 17.4% (175) and 8.5% (86). Maximum, minimum, ending, and median temperatures were similar for those with or without SSI (36.6°C vs 36.5°C, 34.9°C vs 35.0°C, 36.4°C vs 36.2°C, and 36.1°C vs 36.0°C, P = not significant) and percent minutes using incremental cutoffs failed to correlate SSI with temperature. Absolute minutes for higher temperature cutoffs correlated with SSI because of longer procedure times. On multivariable analysis, factors associated with SSI were preoperative diabetes [odds ratio: 1.81 (1.07-3.07), P = 0.022] and blood loss of more than 500 mL [odds ratio: 1.61 (1.01-2.58), P = 0.047]. CONCLUSIONS: Although active rewarming remains an accepted and valid process measure, highly granular anesthesia information system temperature data did not demonstrate a correlation between temperature measures and SSI. SSI prevention efforts should focus on more efficacious interventions as opposed to currently mandated publicly reported normothermia measures.

Colonic volvulus: presentation and management in metropolitan Minnesota, United States.

BACKGROUND: Management approaches for colonic volvulus are infrequently described in the literature in the United States, and many studies only report operative cases. OBJECTIVE: The aim of this study was to define the demographics, diagnostic and treatment approaches, and outcomes for patients with this disorder in the United States. DESIGN: This study is a retrospective review. SETTINGS: The study was conducted at a 7-hospital health system. PATIENTS: All patients diagnosed with colonic volvulus by International Classification of Diseases, Ninth Revision code were included. MAIN OUTCOME MEASURES: The primary outcomes measured were recurrence, complications, and mortality. RESULTS: One hundred three cases of volvulus (50 sigmoid, 53 cecal) were identified in 92 patients. Compared with cecal volvulus, sigmoid volvulus was more common in men, patients with neurologic diagnoses, and residents of skilled nursing home. Eighty-five percent of the cases presented were acutely obstructed. The diagnosis was established by abdominal x-ray (17%), contrast enema study (27%), CT scan (35%), or laparotomy (17%). Abdominal x-rays were insufficient for definitive diagnosis in 85% of cecal and 49% of sigmoid cases (p = 0.002). All patients with cecal volvulus were treated surgically. Seventy-nine percent of patients with sigmoid volvulus underwent successful nonoperative reduction, of whom 38% had subsequent surgery. Fifty-eight percent of patients with sigmoid volvulus were treated operatively. Resection with primary anastomosis was chosen in most cases (78%). Resection with end ostomy (10%), reduction and pexy (7%), and reduction alone (4%) were other approaches. The mortality rate was 5% (cecal 0%, sigmoid 10%; p = 0.012). There were no readmissions for recurrent cecal volvulus. Nonoperative treatment for sigmoid volvulus often failed (48%). Complication rates were higher in sigmoid volvulus cases (cecal 17%, sigmoid 34%; p = 0.047). LIMITATIONS: This study was limited by its retrospective, nonexperimental design. CONCLUSIONS: Although incidences of cecal and sigmoid volvulus are similar in the present series, sigmoid volvuli are more common in men, individuals with neurologic disease, and residents of nursing homes. Plain radiograph is insufficient to confirm cecal volvulus. The diagnosis is most often made with CT scans. The nonoperative management of sigmoid volvulus is associated with a high recurrence rate.

The impact of coronary artery endarterectomy on outcomes during coronary artery bypass grafting.

BACKGROUND: The impact of coronary artery endarterectomy during coronary artery bypass grafting (CABG) has been debated. We examined the early and late outcomes of CABG with endarterectomy (CE) compared to CABG alone. METHODS: Patients undergoing isolated CABG operations from 2003 to 2008 were retrospectively reviewed. We identified 99 patients who underwent CE and 3:1 propensity matched them to 297 CABG-alone patients based upon clinical factors: Society of Thoracic Surgeons (STS) predicted risk of mortality, age, gender, year of surgery, and ejection fraction. Patient risk factors as well as short- and long-term outcomes were compared by univariate and Kaplan-Meier analysis. RESULTS: Preoperative risk factors were similar between patients undergoing CE or CABG alone. Cross-clamp times (95.6 vs. 71.8 minutes, p = 0.0001) and perfusion times (121.8 vs. 92.7 minutes, p = 0.0001) were longer in patients undergoing CE. Operative mortality (4.0% vs. 1.3%, p = 0.112) and postoperative complications were not significantly different between groups. Patients undergoing coronary endarterectomy incurred longer ICU (75.06 vs. 48.64 hours, p = 0.001) and hospital stays (9.01 vs. 7.7 days, p = 0.034). Long-term mortality (mean follow-up = 27.7 ± 17.7 months) was equivalent despite revascularization technique (p = 0.13); however, patients undergoing CE encountered worse overall freedom from myocardial infarction (MI) (p = 0.03). CONCLUSION: Patients undergoing CABG with coronary CE required longer ventilatory support and ICU stay yet have comparable operative mortality, major complication rates, and long-term survival to isolated CABG. Coronary endarterectomy should be considered an acceptable adjunct to CABG for patients with extensive coronary artery disease to achieve complete revascularization.

Identification of risk factors for the development of clostridium difficile-associated diarrhea following treatment of polymicrobial surgical infections.

OBJECTIVE: To identify risk factors for Clostridium difficile-associated diarrhea (CDAD) in surgical patients following treatment of polymicrobial infections. SUMMARY BACKGROUND DATA: Infections among surgical patients are frequently anaerobic or mixed aerobic-anaerobic infections and are therefore subject to polymicrobial antibiotic coverage, including metronidazole. While multiple antibiotics are known to contribute to the development of CDAD, the role of preventive antibiotics is unproven. METHODS: An 11-year dataset of consecutive infections treated in surgical patients at a single hospital was reviewed. All intra-abdominal, surgical site, or skin/skin structure infections were identified. Each infection was evaluated for antibiotic coverage and subsequent CDAD. Antibiotic usage was assessed using chi analysis. A multiple logistic regression was used to identify independent predictors of CDAD. RESULTS: A total of 4178 intra-abdominal, surgical site, or skin/skin structure infections were identified. Of these infections, 98 were followed by CDAD. Only carbapenem use affected the incidence of CDAD: 3.5% of infections treated with a carbapenem were followed by CDAD, whereas only 2.1% of infections treated without carbapenems were followed by CDAD (P = 0.04). Metronidazole had no association with future CDAD. Only age and Acute Physiology and Chronic Health Evaluation II (APACHE II) score were independently associated with CDAD by multiple logistic regression analysis. CONCLUSIONS: Older patients with a high severity of illness are at greatest risk for developing CDAD following treatment of polymicrobial infections. No specific antibiotic class, including fluoroquinolones, is associated with an increased incidence of CDAD in this population. Although use of metronidazole in the treatment of polymicrobial infections is appropriate for anaerobic coverage, it does not reduce the risk of future CDAD.

Obesity and site-specific nosocomial infection risk in the intensive care unit.

BACKGROUND: Obese patients are at higher than normal risk for postoperative infections such as pneumonia and surgical site infections, but the relation between obesity and infections acquired in the intensive care unit (ICU) is unclear. Our objective was to describe the relation between body mass index (BMI) and site-specific ICU-acquired infection risk in adults. METHODS: Secondary analysis of a large, dual-institutional, prospective observational study of critically ill and injured surgical patients remaining in the ICU for at least 48 h. Patients were classified into BMI groups according to the National Heart, Lung and Blood Institute guidelines: or= 40.0 kg/m(2) (severely obese). The primary outcomes were the number and site of ICU-acquired U.S. Centers for Disease Control and Prevention-defined infections. Multivariable logistic and Poisson regression were used to determine age-, sex-, and severity-adjusted odds ratios (ORs) and incidence rate ratios associated with differences in BMI. RESULTS: A total of 2,037 patients had 1,436 infection episodes involving 1,538 sites in a median ICU length of stay of 9 days. After adjusting for age, sex, and illness severity, severe obesity was an independent risk factor for catheter-related (OR 2.2; 95% confidence interval [CI] 1.5, 3.4) and other blood stream infections (OR 3.2; 95% CI 1.9, 5.3). Cultured organisms did not differ by BMI group. CONCLUSION: Obesity is an independent risk factor for ICU-acquired catheter and blood stream infections. This observation may be explained by the relative difficulty in obtaining venous access in these patients and the reluctance of providers to discontinue established venous catheters in the setting of infection signs or symptoms.

Choosing antibiotics for intra-abdominal infections: what do we mean by "high risk"?

BACKGROUND: The definition of "high risk" in intra-abdominal infections remains vague. The purpose of this study was to investigate patient characteristics associated with a high risk of isolation of resistant pathogens from an intra-abdominal source. METHODS: All complicated intra-abdominal and abdominal organ/space surgical site infections treated over a ten-year period in a single hospital were analyzed. Infections were categorized by pathogen(s). Organisms designated "resistant" were those that had a reasonable probability of being resistant to the broad-spectrum agents imipenem/cilastatin and piperacillin/tazobactam, and included non-fermenting gram-negative bacilli (e.g., Pseudomonas aeruginosa), resistant gram-positive pathogens, vancomycin-resistant enterococci, and fungi. Patient characteristics were analyzed to define associations with the risk of isolation of "resistant" pathogens. RESULTS: A total of 2,049 intra-abdominal infections were treated during the period of study, of which 1,182 had valid microbiological data. The two genera of pathogens isolated from more than 25% of health care-associated infections and more commonly than from community-acquired infections were Enterococcus spp. (29%) and Candida spp. (33%). Health care association, corticosteroid use, organ transplantation, liver disease, pulmonary disease, and a duodenal source all were associated with resistant pathogens. By multivariable analysis, several acute and chronic measures of disease were predictive of death, with a strong interaction between solid organ transplantation, resistant pathogens, and death. Other links between specific pathogens and patient characteristics were documented, for example, between fungal infection and a gastric, duodenal, or small bowel source, and between liver transplantation and vancomycin-resistant enterococci. CONCLUSIONS: On the basis of clinical characteristics, it may be possible to identify patients with intra-abdominal infections caused by pathogens that are potentially resistant to broad-spectrum antibacterial agents. Under these circumstances, and if warranted clinically, broadened coverage probably ought to include specific anti-enterococcal and anti-candidal therapy.

Antimicrobial-impregnated surgical incise drapes in the prevention of mesh infection after ventral hernia repair.

BACKGROUND: Antimicrobial surgical incise drapes are used in an effort to lower the risk of mesh infection after hernia repair. The effect such drapes on infection rates was examined. METHODS: Ventral or incisional hernia repairs with mesh from March, 2002, to June, 2006 gathered from the local American College of Surgeons-National Surgical Quality Improvement Project database, chart review, and operating room database were reviewed. Mesh infection was defined as infection necessitating mesh removal. Significant univariate predictors of infection were included in a logistic regression model. Mesh infections were divided into early (0-7 days), midterm (8-50 days), and late (>50 days) onset for subgroup analysis. RESULTS: Five hundred six hernia repairs and 42 mesh infections (8.3%) were identified (range 1-947 days), the latter consisting of seven early (16.7%), 13 midterm (31.0%), and 22 late (53.4%) infections. Antimicrobial-impregnated incise drapes were used in 206 cases in the entire series (59.1%). By multivariable analysis, factors significantly associated with incise drape use were laparoscopic repair (odds ratio [OR] 3.03; p < 0.0001), per-year resident level (OR 1.21; p = 0.0012), high-volume surgeon (OR 1.74; p = 0.021), clean wound classification (OR 2.21; p = 0.0076), current or recent smoking (OR 1.61; p = 0.039), and chronic steroid use (OR 0.31; p = 0.044). Predictors of mesh infection in multivariable analysis were repair of recurrent hernia (OR 3.72; p < 0.0001), current or recent smoking (OR 2.18; p = 0.027), and per-minute operation time (OR 1.007; p = 0.0004). Missed enterotomy was the only factor significantly associated with time to mesh infection (75% in the early group; p < 0.0001). CONCLUSION: At our institution, antimicrobial-impregnated incise drapes are most likely to be used by the highest-volume hernia repair surgeons and more experienced residents in clean, elective, laparoscopic cases. However, reduction in the mesh infection rate was not observed with their use. Independent predictors of mesh infection included repeat surgery, smoking, and longer operating time. The time from operation to mesh infection differed greatly. Not unexpectedly, mesh infection within seven days after implantation was strongly related to a missed enterotomy.

Serum estradiol concentration as a predictor of death in critically ill and injured adults.

BACKGROUND: Whereas animal models of sepsis demonstrate survival benefits for the pro-estrus state, human observational studies have failed to demonstrate a consistent survival advantage among female patients. Estrogen biosynthesis differs substantially in primate and non-primate animals, and estrogens have diverse immunologic actions. Estrogen concentrations are elevated in response to critical illness and injury (regardless of sex), and elevated concentrations of serum estradiol are associated with a higher mortality rate. Our objective was to determine the predictive ability and test characteristics of the serum estradiol concentration at 48 h in critically ill patients. METHODS: A prospective cohort study of surgical and trauma adult intensive care unit patients at two academic tertiary-care centers. Sex hormones (estradiol, progesterone, testosterone, prolactin, and dehydroepiandrosterone) and cytokines were assayed at 48 h, and the 28-day all-cause mortality rate was assessed. RESULTS: There was no difference in mortality rates between the sexes (survivors being male in 75.2% of cases vs. 76.0% in non-survivors; p = 0.43). The serum estradiol concentration was significantly elevated in non-survivors regardless of sex (median 18.7 pg/mL [interquartile range {IRQ} 9.99-43.6] in survivors and 40.7 pg/mL [IQR 9.99-94.8] in non-survivors; p < 0.001). The area under the receiver-operating characteristic (ROC) curve for serum estradiol was 0.64 (95% confidence interval [CI] 0.55, 0.72). The parameter with the largest ROC curve was the Acute Physiology and Chronic Health Evaluation (APACHE) II score (0.75; 95% CI 0.68, 0.82). A serum estradiol cut-point of 50 pg/mL was 48% sensitive and 80% specific in predicting death and classified the outcome of 76% of patients correctly. CONCLUSIONS: Serum estradiol concentration is a valuable prognostic tool and potential contributor to adverse outcomes of critically ill or injured surgical patients.

Reduction in rates of methicillin-resistant Staphylococcus aureus infection after introduction of quarterly linezolid-vancomycin cycling in a surgical intensive care unit.

BACKGROUND: The burden of infection with antibiotic-resistant gram-positive cocci, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE), continues to increase, leading to substantial morbidity and high mortality rates, particularly in intensive care units (ICUs). Creative interventions may be required to reverse or stabilize this trend. METHODS: The efficacy of empiric cycling of antibiotics active against gram-positive organisms was tested in a before-after intervention in a single surgical ICU. Four years of baseline data were compared with two years of data compiled after the implementation of a strategy where the empiric antibiotic of choice for the treatment of gram-positive infections (linezolid or vancomycin) was changed every three months. Whatever the initial choice of drug, if possible, the antibiotic was de-escalated after final culture results were obtained. The rates of all gram-positive infections were analyzed, with a particular focus on MRSA and VRE. Concurrently, similar outcomes were followed for patients treated on the same services but outside the ICU, where cycling was not practiced. RESULTS: During the four years prior to cycling, 543 infections with gram-positive organisms were acquired in the ICU (45.3/1,000 patient-days), including 105 caused by MRSA (8.8/1,000 patient days) and 21 by VRE (1.8/1,000 patient-days). In the two years after implementation of cycling, 169 gram-positive infections were documented (28.1/1,000 patient-days; p < 0.0001 vs. non-cycling period), including 11 caused by MRSA (1.8/1,000 patient-days; p < 0.0001 vs. non-cycling period). The percentage of S. aureus infections caused by MRSA declined from 67% to 36%. The rate of infection with VRE was unchanged. Outside the ICU, the yearly numbers of infections with both MRSA and VRE increased over time. CONCLUSION: Quarterly cycling of linezolid and vancomycin in the ICU is a promising method to reduce infections with MRSA.

Outbreak of resistant Pseudomonas aeruginosa infections during a quarterly cycling antibiotic regimen.

BACKGROUND: Antibiotic cycling or rotation of antimicrobial agent classes has been proposed to combat antimicrobial resistance. METHODS: A prospective cohort study was conducted in a medical intensive care unit (ICU) of a university hospital between December 1, 2000, and September 30, 2002, as part of a three-center trial under the aegis of the U.S. Centers for Disease Control and Prevention. Patients admitted to the medical ICU for > 48 h were enrolled, and demographic and microbiological data were collected until discharge or death. Baseline data were collected for four months (12/1/00 to 3/31/01) and compared with data collected after institution of a quarterly cycling regimen (cycle order: Cefepime, ciprofloxacin, piperacillin-tazobactam, imipenem-cilastatin) for the empiric treatment of gram-negative infections (4/01/01 to 9/30/02). RESULTS: Of 1,074 consecutive admissions, 301 were enrolled, 59 during baseline and 242 during the cycling periods. An outbreak of multi-drug resistant Pseudomonas aeruginosa followed cycle 2 (cefepime), coinciding with cycles 3 and 4 (ciprofloxacin and piperacillin-tazobactam) (80.0 and 73.7 vs. 37.3 isolates/100 patients enrolled for cycles 3/4 and baseline, respectively; p = 0.04). Acinetobacter spp. were isolated less frequently during the cycling periods (15.3 vs. 1.2 isolates/100 patients for baseline and cycling periods, respectively; p > or = 0.01). The crude hospital mortality rate was similar (24/59 [41%] baseline vs. 73/242 [30%] cycling; p = 0.16) between periods. However, the percentage of patients admitted to the medical ICU who subsequently acquired an infection followed by in-hospital death was higher at baseline than during cycling: 15/59 (25.4%) vs. 33/242 (13.6%)(p = 0.04). CONCLUSIONS: In this study, the cycling strategy was not definitively associated with beneficial changes in unit epidemiology and in fact may have contributed to an outbreak of multi-drug resistant P. aeruginosa.

Cutaneous metastases in patients with rectal cancer: a report of six cases.

Cutaneous metastases from rectal cancer are rare manifestations of disseminated disease and uniformly represent dismal survival. A retrospective review of six patients with rectal cancer metastatic to the dermis was performed. The diagnosis of rectal cancer was made concurrently with the diagnosis of the dermal metastases in all six patients. A 100 per cent histopathologic concordance existed between the tissue of the dermal metastases and primary rectal tumor. The progression of systemic metastatic disease was the cause of death in 83.3 per cent of patients (5/6). No patient survived more than 7 months from the time of diagnosis. Recognition of suspicious skin lesions as possible harbingers of undiagnosed visceral malignancy is important in managing patients both with and without a history of previous cancer.

High levels of endogenous estrogens are associated with death in the critically injured adult.

BACKGROUND: Sex hormones exhibit predictable changes in their physiologic patterns during critical illness. Endogenous estrogens are elevated in both genders as a result of the peripheral conversion of androgens to estrogens by the aromatase enzyme. Elevated endogenous estrogens have been associated with death in medical and mixed surgical intensive care unit (ICU) patients. Our objective was to determine the relationship between endogenous estrogens and outcomes in critically injured patients. METHODS: A prospective cohort of injured patients remaining in the ICU for at least 48 hours at two trauma centers was enrolled. Sex hormones (estradiol, progesterone, testosterone, prolactin, and dehydroepiandrosterone-sulfate) were assayed and mortality was assessed. A logistic regression model was used to determine the association between estradiol and death. The area under the receiver operating characteristic (AUROC) curve was used to estimate the accuracy of estradiol in predicting death. RESULTS: Nine hundred ninety-one patients were enrolled with a 13.4% mortality rate. Despite no detectable difference in mortality among genders, estradiol was significantly elevated in nonsurvivors (16 pg/mL vs. 35 pg/mL, p < 0.001). Estradiol was a marker for injury severity with the most severely injured patients exhibiting the highest levels. The ability of estradiol to predict death (AUROC = 0.65) was comparable with Trauma and Injury Severity Score (AUROC = 0.65) and superior to Injury Severity Score (AUROC = 0.54) in this cohort. CONCLUSIONS: Serum estradiol is a marker of injury severity and a predictor of death in the critically injured patient, regardless of gender. Whether or not estradiol plays a causal role in outcomes is unclear, but estrogen modulation represents a potential therapy for improving outcomes in critically ill trauma patients.

Is fever protective in surgical patients with bloodstream infection?

BACKGROUND: Sepsis from bloodstream infection (BSI) is an important cause of morbidity and mortality among surgical patients. Our hypothesis was that fever and leukocytosis during BSI would be associated with gram-negative pathogens and worse outcomes among hospitalized surgical patients. STUDY DESIGN: A prospectively collected dataset of all infections diagnosed on the adult general and trauma surgery services between December 1996 and December 2005 at the University of Virginia Hospital was reviewed. Fever was considered a temperature of > or = 38.5 degrees C, and leukocytosis was defined as a white blood cell count > or = 15,000/microL within 24 hours of treatment for infection. Logistic regression was used to identify predictors of fever and mortality. RESULTS: Over 9 years, 823 BSIs were analyzed. One hundred forty-eight BSIs resulted in death (18.0%), and 541 (65.7%) patients were febrile at diagnosis; mortality for these two groups were 12.9% and 27.7%, respectively (p < 0.0001). Febrile patients had a trend toward fewer gram-negative infections (27.0% versus 31.9%, p = 0.13), 403 had a leukocytosis at diagnosis and 420 did not; mortality for the two groups was 19.1% and 16.9%, respectively (p = NS). Higher maximum temperature was protective against mortality in the logistic regression analysis (odds ratio = 0.60 per C degrees, p < 0.0001). CONCLUSIONS: Among surgical patients with sepsis, fever during BSI was not associated with a gram-negative cause and correlated with survival, although increasing WBC had little effect. Mortality after BSI appears associated more with an initially blunted physiologic response than with a robust, proinflammatory response. In addition, a threshold for blood culture other than temperature > or = 38.5 degrees C should be considered.

Whence Resistance?

BACKGROUND: Antimicrobial resistance results from a complex interaction between pathogenic and non-pathogenic bacteria, antimicrobial pressure, and genes, which together comprise the total body of potential resistance elements. The purpose of this study is to review and evaluate the importance of antimicrobial pressure on the development of resistance in a single surgical intensive care unit. METHODS: We reviewed a prospectively collected dataset of all intensive care unit (ICU)-acquired infections in surgical and trauma patients over a 6-y period at a single hospital. Resistant gram-negative pathogens (rGNR) included those resistant to all aminoglycosides, quinolones, penicillins, cephalosporins, or carbapenems; resistant gram-positive infections (rGPC) included methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant enterococci (VRE). Each resistant infection was evaluated for prior or concomitant antibiotic use, previous treatment for the same (non-resistant) organism, and concurrent infection with the same organism (genus and species, although not necessarily resistant) in another ICU patient. RESULTS: Three hundred and thirty resistant infections were identified: 237 rGNR and 93 rGPC. Infections with rGNR occurred frequently while receiving antibiotic therapy (65%), including the sensitive form of the subsequent resistant pathogen (42.2%). Infections with rGPC were also likely to occur on antimicrobial therapy (50.6%). Treatment of a different patient for an infection with the same resistant pathogen in the ICU at the time of diagnosis, implying potential patient-to-patient transmission occurred more frequently with rGNR infections (38.8%). CONCLUSION: Antimicrobial pressure exerts a substantial effect on the development of subsequent infection. Our data demonstrate a high estimated rate of de novo emergence of resistance after treatment, which appears to be more common than patient-to-patient transmission. These data support the concept that efforts to limit antimicrobial usage will be more efficacious than enhanced isolation procedures when trying to reduce antimicrobial resistance.

In the Absence of a Mechanical Bowel Prep, Does the Addition of Pre-Operative Oral Antibiotics to Parental Antibiotics Decrease the Incidence of Surgical Site Infection after Elective Segmental Colectomy?

BACKGROUND: Pre-operative oral antibiotics administered the day prior to elective colectomy have been shown to decrease the incidence of surgical site infections (SSI) if a mechanical bowel prep (MBP) is used. Recently, the role for mechanical bowel prep has been challenged as being unnecessary and potentially harmful. We hypothesize that if MBP is omitted, oral antibiotics do not alter the incidence of SSI following colectomy. METHODS: We selected patients who underwent an elective segmental colectomy from the 2012 and 2013 National Surgical Quality Improvement Program colectomy procedure targeted database. Indications for surgery included colon cancer, diverticulitis, inflammatory bowel disease, or benign polyp. Patients who received mechanical bowel prep were excluded. The primary outcome measured was surgical site infection, defined as the presence of superficial, deep or, organ space infection within 30 d from surgery. RESULTS: A total of 6,399 patients underwent elective segmental colectomy without MBP. The incidence of SSI differed substantially between patients who received oral antibiotics, versus those who did not (9.7% vs. 13.7%, p=0.01). Multivariate analysis indicated that age, smoking status, operative time, perioperative transfusions, oral antibiotics, and surgical approach were associated with post-operative SSI. When controlling for confounding factors, the use of pre-operative oral antibiotics decreased the incidence of surgical site infection (odds ratio=0.66, 95% confidence interval=0.48-0.90, p=0.01). CONCLUSION: Even in the absence of mechanical bowel prep, pre-operative oral antibiotics appear to reduce the incidence of surgical site infection following elective colectomy.

Hospital costs and risk factors associated with complications of the ileal pouch anal anastomosis.

BACKGROUND: The purpose of this study was to estimate the costs associated with the most common complications of the ileal pouch anal anastomosis (IPAA) and identify factors that predispose to them. METHODS: Hospital costs of 135 patients undergoing the IPAA were combined with information abstracted from charts. Logistic and linear regression modeling were used to estimate the marginal costs for the most common IPAA complications and determine factors predisposing to their occurrence. RESULTS: The average overall cost for the IPAA was $20,865. Just more than half (53%) of patients experienced complications, the 3 most common being small-bowel obstruction (24.4%), pelvic/abdominal sepsis (6.7%), and dehydration (5.9%). The average cost to treat an episode of small-bowel obstruction was $6709. Treatment of pelvic/abdominal sepsis averaged $9268 per occurrence, whereas dehydration averaged $4860. Steroid use > 3 months before colectomy significantly increased the risk for any complication (P =.02). No factors were found to be good predictors of bowel obstruction. However, age > 42 years and low patient hematocrit were significant predictors of dehydration as a complication (P <.05). Trending toward significance were urgent operation and weight loss greater than 5%. CONCLUSIONS: The most common complications of the IPAA are small-bowel obstruction, pelvic/abdominal sepsis, and dehydration. Complications were responsible for approximately 44% of the overall cost of an IPAA. Factors that increase risk of IPAA complications are steroid use, low hematocrit, age > 42 years, nonelective procedures, and preoperative weight loss.

Characteristics of surgical patients receiving inappropriate empiric antimicrobial therapy.

BACKGROUND: Inappropriate antibiotics have been observed to result in an increased duration of antibiotic treatment and hospital length of stay, development of multidrug-resistant organisms, and mortality rate compared with appropriate antibiotic treatment. Few studies have evaluated independent risk factors associated with inappropriateness. The purpose of this study was to identify independent predictors of inappropriate, empiric antimicrobial therapy for the treatment of severe sepsis. METHODS: This was a retrospective analysis of a prospectively maintained database of all surgical/trauma patients admitted to a tertiary care center from 1996 to 2007 and treated for sepsis. "Appropriate" empiric antibiotic treatment was determined by sensitivity testing. Demographics and comorbidities, infection sites, infection organisms, and outcomes between strata were compared. Differences in outcome were estimated using relative risk and 95% confidence intervals for correlated data. RESULTS: A total of 2,855 patients (7,158 infections) were identified. Independent predictors of inappropriate, empiric antimicrobial therapy for the treatment of severe sepsis included site of infection and organism type. Severity of illness, age, medical conditions, and community versus health care-associated infections were not associated with inappropriate therapy. Although inappropriate empiric therapy was associated with a longer length of stay and duration of antimicrobial use, it did not result in higher mortality. CONCLUSION: Our study observed that inappropriate empiric antibiotic selection is related to site of infection and pathogen. Other clinical variables do not appear to predict inappropriateness of antibiotic treatment. Efforts should be focused on early broad-spectrum therapy and more rapid microbiologic methods. LEVEL OF EVIDENCE: Therapeutic/care management study, level II.

Does it Matter if we get it right? Impact of appropriateness of empiric antimicrobial therapy among surgical patients.

Previous studies have shown conflicting evidence regarding the impact of inappropriate, initial antibiotic therapy. The purpose of this study was to evaluate the impact of inappropriate empiric antimicrobial therapy for the treatment of infection among surgical patients. We hypothesized that inappropriate empiric antimicrobial therapy would predict increased mortality risk compared with appropriate therapy. This was a retrospective analysis of a prospectively maintained database of all surgical patients admitted to a tertiary care center from 1996 to 2007 and treated for sepsis. "Appropriate" empiric antibiotic treatment was determined by sensitivity testing. Demographics and comorbidities, infection sites, infection organisms, and outcomes were compared between inappropriately and appropriately treated groups. Multivariable log-binomial regression was performed. There were 2,855 patients (7,158 infectious episodes) identified by culture analysis as either appropriately or inappropriately treated. Three hundred seventeen (15%) inappropriately treated infectious episodes resulted in death compared with 718 (14%) of the appropriately treated infectious episodes. After adjusting for statistically significant variables, inappropriately treated episodes of infection were not found to be associated with an increased risk for mortality compared with appropriately treated episodes of infection (relative risk, 1.0; 95% confidence interval, 0.99 - 1.02; P = 0.36). Our study observed no difference in mortality between appropriately and inappropriately treated infections within a surgical population.