Wound Culture Utility in Negative Surgical Exploration for Necrotizing Soft Tissue Infection.

Early surgical intervention decreases mortality in necrotizing soft tissue infections (NSTIs). Yet, a subset of patients will not have NSTIs (non-NSTIs) at the time of exploration. We hypothesized that NSTI and non-NSTI patients had similar causative organisms and that intraoperative wound cultures could help guide management. Culture results and outcomes were compared for all patients undergoing surgery for suspected NSTIs over a seven-year-period. Of 295 patients, 240 (81.4%) had NSTIs. Of the 55 non-NSTI patients (18.6%), 50 had cellulitis and 5 had abscesses. NSTI and non-NSTI patients had similar rates of bacteremia (20.4% vs 17.6%, P = 0.66), septic shock (15.9% vs 12.7%, P = 0.68), and mortality (10.4% vs 7.2%, P = 0.62). Wound cultures were collected more often in NSTI patients (229/240, 95.4%) than in non-NSTI patients (42/55, 76.4%, P < 0.01). Non-NSTI patients had positive deep wound cultures more than half of the time (23/42, 54.8%). The microbiologic profile was similar between groups, with Methicillin Resistant Staphylococcus aureus and Group A Streptococcus occurring with the same frequency. We advocate for deep wound cultures in all patients being evaluated operatively for NSTIs even if the exploration is considered negative because these patients have similar clinical characteristics and virulent microbiology, and culture results can help guide antimicrobial therapy.

Chance to cut: defining a negative exploration rate in patients with suspected necrotizing soft tissue infection.

BACKGROUND: Necrotizing soft tissue infections (NSTI) are aggressive infections associated with significant morbidity and mortality. Despite multiple predictive models for the identification of NSTI, a subset of patients will not have an NSTI at the time of surgical exploration. We hypothesized there is a subset of patients without NSTI who are clinically indistinguishable from those with NSTI. We aimed to characterize the differences between NSTI and non-NSTI patients and describe a negative exploration rate for this disease process. METHODS: We conducted a retrospective review of adult patients undergoing surgical exploration for suspected NSTI at our county-funded, academic-affiliated medical center between 2008 and 2015. Patients were identified as having NSTI or not (non-NSTI) based on surgical findings at the initial operation. Pathology reports were reviewed to confirm diagnosis. The NSTI and non-NSTI patients were compared using χ2 test, Fisher's exact test, and Wilcoxon rank-sum test as appropriate. A p value <0.05 was considered significant. RESULTS: Of 295 patients undergoing operation for suspected NSTI, 232 (79%) were diagnosed with NSTI at the initial operation and 63 (21%) were not. Of these 63 patients, 5 (7.9%) had an abscess and 58 (92%) had cellulitis resulting in a total of 237 patients (80%) with a surgical disease process. Patients with NSTI had higher white cell counts (18.5 vs. 14.9 k/mm3, p=0.02) and glucose levels (244 vs. 114 mg/dL, p<0.0001), but lower sodium values (130 vs. 134 mmol/L, p≤0.0001) and less violaceous skin changes (9.2% vs. 23.8%, p=0.004). Eight patients (14%) initially diagnosed with cellulitis had an NSTI diagnosed on return to the operating room for failure to improve. CONCLUSIONS: Clinical differences between NSTI and non-NSTI patients are subtle. We found a 20% negative exploration rate for suspected NSTI. Close postoperative attention to this cohort is warranted as a small subset may progress. LEVEL OF EVIDENCE: Retrospective cohort study, level III.

Careful Patient Selection Achieves High Radiocephalic Arteriovenous Fistula Patency in Diabetic and Female Patients.

BACKGROUND: The radiocephalic arteriovenous fistula (rcAVF) is considered the first-choice site for hemodialysis access; however, it has been associated with decreased rates of patency and maturation in women and diabetic patients in some studies. We hypothesized that careful preoperative selection of patients for an rcAVF fistula would result in a high 1-year patency rate and that external factors, such as female gender and diabetes mellitus (DM), would not adversely affect fistula patency. METHODS: This is a retrospective study of all patients who underwent rcAVF creation at a single institution from January 2011 to June 2016. Patients were carefully selected based on clinical examination and preoperative, B-mode, ultrasound findings. Primary patency and primary assisted patency at 1 year were calculated. Survival analysis was also conducted to evaluate for factors associated with rcAVF patency. RESULTS: There were 158 patients identified who underwent rcAVF fistula creation and were seen in follow-up. The 1-year primary and primary assisted patency rates were 62% and 81%, respectively. On Kaplan-Meier survival analysis, there was no difference in rcAVF patency with respect to gender, Hispanic race, anesthesia type, DM, and smoking status. Patients with a prior AVF, most often received in the nondominant arm and now receiving an rcAVF in the dominant arm, had a significantly higher risk of fistula failure, in both primary and primary assisted patency survival (hazard ratio 5.1, 95% confidence interval 1.6-16.2, P = 0.06). Patients without a history of hypertension (HTN), as noted in the electronic medical records, trended toward a higher risk of primary assisted patency rcAVF failure, compared to those who had a history of HTN (hazard ratio 3.0, 95% confidence interval 1.1-7.9, P = 0.03). CONCLUSIONS: With careful patient selection, the rcAVF can achieve a high 1-year primary assisted patency rate. Female gender and DM were not significantly associated with an increase in rcAVF failure and should not be heavily relied on in-patient selection. First-time AVF patients and patients with a history of HTN may be associated with increased rcAVF patency.

Assessing outcomes and costs of appendectomies performed at rural hospitals.

BACKGROUND: The purpose of our study was to assess the outcomes and costs of appendectomies performed at rural and urban hospitals. METHODS: The National Inpatient Sample (2001-2012) was queried for appendectomies at urban and rural hospitals. Outcomes (disease severity, laparoscopy, complications, length of stay (LOS), and cost) were analyzed. RESULTS: Rural patients were more likely to be older, male, white, and have Medicaid or no insurance. Rural hospitals were associated with higher negative appendectomy rates (OR = 1.26,95%CI = 1.18-1.34,p < 0.01), less laparoscopy use (OR = 0.65,95%CI = 0.58-0.72,p < 0.01), and slightly shorter LOS (OR = 0.98,95%CI = 0.97-0.99,p < 0.01). There was no consistent association with perforated appendicitis and no difference in complications or costs after adjusting for hospital volume. Yearly trends showed a significant increase in the cases utilizing laparoscopy each year at rural hospitals. CONCLUSIONS: Rural appendectomies are associated with increased negative appendectomy rates and less laparoscopy use with no difference in complications or costs compared to urban hospitals.