Negative Pressure Wound Therapy With and Without Instillation in Necrotizing Soft Tissue Infections

Background: Necrotizing soft tissue infections (NSTIs) are rare but deadly infections that require early and often extensive surgical debridement. After debridement, patients frequently have substantial morbidity because of large, open wounds. Hypothesis: Negative pressure wound therapy with instillation (NPWTi) results in higher wound closure rates compared with traditional negative pressure wound therapy (NPWT) or wet to dry dressings (moist wound care dressing). Patients and Methods: A prospectively maintained Acute and Critical Care Surgery database spanning 2008-2018 was queried for patients with a diagnosis of necrotizing fasciitis, Fournier gangrene, or gas gangrene. Data were collected on patient comorbidities, operative management, and clinical outcomes. Patients were stratified by use of moist wound care dressing, traditional NPWT, or NPWTi. Data were analyzed using analysis of variance (ANOVA), χ2, and logistic regression. Results: During the 10-year study period, patients were treated for NSTI; 173 were managed with moist wound care dressing, 150 with NPWT, and 48 with NPWTi. Patients were similar in terms of demographics, body mass index (BMI), diabetes mellitus, and smoking rates. Overall, complication rates were not substantially different, but mortality was higher in the moist wound care dressing group (16.2% vs. 10.7% NPWT vs. 2.1% NPWTi; p = 0.02). In the moist wound care dressing group, 81.5% of patients had an open wound at discharge compared with 52.7% of the NPWT group and only 14.6% of the NPWTi group (p < 0.001). On multivariable regression, NPWTi was associated with closure rates five times higher than the NPWT group (odds ratio [OR], 5.28; 95% confidence interval [CI], 2.40-11.61; p < 0.001) after controlling for smoking status, intravenous drug use, number of operations, and involvement of the most common region of the body. Conclusions: Negative pressure wound therapy with instillation is associated with higher rates of wound closure without increasing complication rates in patients with NSTI compared with traditional NPWT or moist wound care dressing. Although prospective studies are needed, this indicates the potential to improve patient quality of life through reduced pain and outpatient home health needs.

Does Negative Pressure Wound Therapy Impact the Outcome for Patients With Necrotizing Soft Tissue Infection Infected With Anaerobic Bacteria?

Background: A notable improvement in the treatment of necrotizing soft tissue infections (NSTIs) is the development of negative pressure wound therapy (NPWT). Clinicians are still debating whether NPWT is as successful as conventional wet-to-dry dressings at removing bacteria. Recent research has revealed potential oxygen deprivation effects of NPWT in underlying wound tissues, although clinical trials regarding the effects of reduced oxygen on anaerobic bacterial soft tissue infections remain noticeably lacking. Hypothesis: We hypothesized that NPWT-treated patients with NSTIs who were solely infected by anaerobic bacteria would have worse outcomes than those who were infected with other bacterial species. Patients and Methods: Our study included a retrospective examination of the 2008-2022 period of our Acute and Critical Care Surgery database. Patients who had been identified as having necrotizing fasciitis, Fournier gangrene, or gas gangrene and who had their conditions verified by positive wound cultures acquired during the initial debridement and subsequently received NPWT made up the study cohort. Comorbidities, surgical techniques, and clinical results were all covered by the data. Based on their wound infections, patients were divided into two groups: those with exclusively anaerobic NSTIs and those with different bacterial groups (such as polymicrobial and aerobic). Multiple regression, χ2 analysis, and analysis of variance (ANOVA) were among the analytical methods used. Results: One hundred twelve patients with NSTI who had received NPWT comprised the study cohort. Sixteen of these patients (14.3%) had NSTIs that were exclusively anaerobic, whereas the remaining 96 (85.7%) had NSTIs that were mixed aerobic, facultative, or polymicrobial. Between the two groups, there was no difference in the initial wound size. Patients with anaerobic NSTI who underwent NPWT showed a statistically significant increase in the number of debridements (3 [interquartile range {IQR},1-9] vs. 2 [IQR, 1-4]; p = 0.012) and an increased 100-day re-admission rate (37.5% vs. 12.5%; p = 0.012) when compared with patients with non-anaerobic NSTI. The 100-day re-admission rate increased three-fold in NPWT-treated anaerobic NSTIs, according to a logistic regression analysis (odds ratio [OR], 3.63; 95% confidence interval [CI], 1.06-12.44; p = 0.04). Conclusions: In contrast to patients with other bacterial strains, our data show that patients with NSTI treated with NPWT who only have anaerobic bacterial infections have a larger number of debridements and are much more likely to require re-admission within 100 days. We call for additional prospective studies to be conducted to identify additional risk factors and consider alternate treatment options for individuals with exclusively anaerobic NSTIs in light of these findings.

Fifteen-minute Frequency of Glucose Measurements and the Use of Threshold Alarms: Impact on Mitigating Dysglycemia in Critically Ill Patients

BACKGROUND

The use of near-continuous blood glucose (BG) monitoring has the potential to improve glycemic control in critically ill patients. The MANAGE IDE trial evaluated the performance of the OptiScanner (OS) 5000 in a multicenter cohort of 200 critically ill patients.

METHODS

An Independent Group reviewed the BG run charts of all 200 patients and voted whether unblinded use of the OS, with alarms set at 90 and 130 to 150 mg/dL to alert the clinical team to impending hypoglycemia and hyperglycemia, respectively, would have eliminated episodes of dysglycemia: hypoglycemia, defined as a single BG <70 mg/dL; hyperglycemia, defined as >4 hours of BG >150 mg/dL; severe hyperglycemia, defined as >4 hours of BG >200 mg/dL and increased glucose variability (GV), defined as coefficient of variation (CV) >20%.

RESULTS

At least one episode of dysglycemia occurred in 103 (51.5%) of the patients, including 6 (3.0%) with hypoglycemia, 83 (41.5%) with hyperglycemia, 18 (9.0%) with severe hyperglycemia, and 40 (20.0%) with increased GV. Unblinded use of the OS with appropriate alarms would likely have averted 97.1% of the episodes of dysglycemia: hypoglycemia (100.0%), hyperglycemia (96.4%), severe hyperglycemia (100.0%), and increased GV (97.5%). Point accuracy of the OS was very similar to that of the point of care BG monitoring devices used in the trial.

CONCLUSION

Unblinded use of the OS would have eliminated nearly every episode of dysglycemia in this cohort of critically ill patients, thereby markedly improving the quality and safety of glucose control.

748. Epidemiology and Outcomes of Invasive Fungal Infections Following Civilian Trauma

Background

Invasive fungal infections (IFI) following traumatic injury are devastating complications that threaten life and limb. In military combat wounds, post-traumatic IFI patients have up to 6 times higher mortality rates and 2.6-5.1 times higher rate of high-level amputations compared to non-IFI patients, though no such data exists for the civilian population. This study is the first cohort to analyze a post-traumatic civilian population for IFI, its epidemiology and outcomes.

Methods

We conducted a single-center retrospective cohort study of all trauma patients over the age of 18 years admitted to a large tertiary referral hospital between 2004 to 2015 who required surgery for their injury and had operative cultures submitted from their wounds. Patient demographics, comorbid conditions, mechanisms of trauma, environmental exposures, and laboratory data were included for analysis. Patients with positive culture for fungus from a site compatible with IFI were considered IFI patients. Data was analyzed using descriptive statistics with p≤0.05 considered significant.

Results

Our cohort includes 1,107 patients that met inclusion criteria. Of these, 120 patients had a positive culture for fungus, 454 patients had a positive culture for bacteria and 533 patients had no positive culture from a site of interest. Basic patient demographics, geographical setting of the trauma, and anatomical site of injury were not significantly associated with having a positive fungal culture. Necrosis was present in 19 (15.8%) IFI vs. 74 (7.5%) non-IFI patients (p=0.002). Soil contamination of a wound was present in 6 (5.0%) IFI vs. 11 (1.1%) non-IFI patients (p=0.001). 55.8% of 120 IFI wounds penetrated below fascial layers compared to 26.7% of 987 non-IFI wounds (p< 0.001).

Presence of IFI increased likelihood of requiring amputation (6.7% vs. 2.7%, p=0.02) and prolonged hospitalization >14 days (77.5% vs. 57.4%, p< 0.001) compared to those without.

Conclusion

IFI significantly increased patient risk for amputation and prolonged hospital length of stay following traumatic injury in a civilian population. Presence of IFI was associated with wounds penetrating below the fascial layer, presence of wound necrosis, and soil contamination of a wound.

Disclosures

Andrej Spec, MD, MSCI, Astellas (Grant/Research Support)Mayne (Consultant)Scynexis (Consultant)

Acute Acalculous Cholecystitis-Associated Bacteremia Has Worse Outcome

Background: Acute acalculous cholecystitis (AAC) is an inflammation of the gallbladder without gallstones in the setting of critical illness. It represents 2%-15% of acute cholecystitis (AC) cases. Bacteremia is associated with increased morbidity and mortality rates in patients in the intensive care unit (ICU). The incidence of bacteremia in acute calculous cholecystitis (ACC) has been described; however, the incidence of bacteremia in AAC has not been reported. We hypothesized that patients with AAC have higher bacteremia rates, leading to worse outcomes than in those with ACC. Methods: A prospectively collected acute care surgery (ACS) institutional database of patients treated from 2008 through 2018 was queried for patients having ACC using International Classification of Diseases (ICD) 9 and 10 codes. Demographics, microbiology findings, and outcomes were extracted. Only patients with positive blood cultures were included in the study. We defined two cohorts: AAC with bacteremia and ACC with bacteremia. The Student t-test was used for continuous variables and the χ² and Fisher exact tests for categorical variables. Multivariable regression was applied, and statistical significance was set at p < 0.05. Results: Of 323 patients with AC, 57 (17.6%) had AAC and 266 (82.4%) had ACC. Of the 19 patients who had a blood culture, 11 (57.8%) were positive. Patients with positive blood cultures had a mean age of 56.7 ± 15.3 years and a mean Body Mass Index (BMI) of 26.7 ± 4.9. The incidence of bacteremia was significantly higher in AAC (n = 6; 10.5% versus n = 5; 1.9 %; p = 0.005), although the time between admission and diagnosis of bacteremia was similar in the two groups (1.2 ± 1.1 versus 0.2 ± 0.5 days; p = 0.128). The patients with AAC and bacteremia were younger (53.8 ± 19.2 versus 60.2 ± 8 years; p = 0.021) and had a longer ICU length of stay (LOS) (12.6 ± 7.2 versus 1.3 ± 2.1 days; p = 0.030). However, there was no difference in the mortality rate in the groups (n = 2; 33.3% versus 1; 20.0%; p = 1.000). After adjusting for age, gender, BMI, and Charlson Comorbidity Index, bacteremia in AAC patients was found to be an independent variable for longer ICU LOS (odds ratio 8.8; 95% confidence interval 1.7-15.9; p = 0.024). Conclusions: The incidence of bacteremia in patients with AAC is five-fold higher and the ICU stay eight days longer than in patients with ACC.

Temporary Abdominal Closure Is Associated with Increased Risk for Fungal Intra-Abdominal Infections in Trauma Patients

Background: Fungal infections are associated with increased morbidity and death. Few studies have examined risk factors associated with post-operative fungal intra-abdominal infections (FIAIs) in trauma patients after exploratory laparotomy. In this study, we evaluated potential risk factors for acquiring post-operative FIAIs and their impact on clinical outcomes. Methods: This was a retrospective analysis of trauma patients admitted from 2005 to 2018 who underwent exploratory laparotomy and subsequently had development of intra-abdominal infection (IAI). Demographics, comorbidities, culture data, antimicrobial usage, Injury Severity Scores (ISS), and clinical outcomes were abstracted. All post-operative IAIs were evaluated and stratified as either bacterial, fungal, combined, and with or without colonization. All groups were compared. Risk factors for the development of post-operative IAI and clinical outcomes were analyzed by Student t test and chi-square test. Multi-variable logistic regression was used to determine independent predictors of post-operative FIAIs. Results: There were 1675 patients identified as having undergone exploratory laparotomy in the setting of traumatic injury, 161 of whom were suspected of having IAI. A total of 105 (6.2%) patients had a diagnosis of IAI. Of these patients, 40 (38%) received a diagnosis of FIAI. The most common fungal pathogens were unspeciated yeast (48.3%), followed by Candida albicans (42.7%), C. glabrata (4.5%), C. dubliniensis (2.25%), and C. tropicalis (2.25%). There were no significant differences in demographics, comorbidities, and percentage of gastric perforations between FIAI and bacterial IAI (BIAI) groups. Patients with FIAIs, however, had a 75% temporary abdominal closure (TAC) rate compared with 51% in BIAIs (p = 0.01). The FIAI group had higher ISS (27 vs. 22, p = 0.03), longer hospital days (34 vs. 25, p = 0.02), and longer intensive care unit (ICU) days (17 vs. 9, p = 0.006) when compared with BIAI. The FIAI group also had a five-fold greater mortality rate. Logistic regression identified TAC as an independent risk factor for the development of post-operative FIAIs (odds ratio [OR] 6.16, confidence interval [CI] 1.14-28.0, p = 0.02). Conclusions: An FIAI after exploratory laparotomy was associated with greater morbidity and death. A TAC was associated independently with increased risk of FIAI after exploratory laparotomy in the setting of traumatic injury. Clinicians should suspect fungal infections in trauma patients in whom post-operative IAI develops after undergoing exploratory laparotomy using TAC techniques.

Inadequate Antibiotic Therapy Results in Higher Recurrence Rate after Drainage of Complicated Peri-Rectal Abscess

Background: Recommended treatment for complicated peri-rectal abscess is incision and drainage (I&D) in conjunction with antibiotics. However, there is no standard antibiotic regimen for post-operative therapy described in the published literature. Our hypothesis was that appropriate post-operative antibiotic therapy after emergency I&D of complicated peri-rectal abscess will improve patient outcomes. Methods: Data from 58 patients with complicated peri-rectal abscess who underwent emergency I&D were analyzed retrospectively. Demographic, microbiologic, and antibiotic data were abstracted. Adequateness of antibiotics was judged by susceptibility data when available or by comparing the antibiotic spectrum with the type of organisms grown in culture when susceptibility data were not available. The Student t-test and χ² test were used to analyze continuous and categorical variables, respectively. Multivariable analysis was used to adjust for confounding variables influencing recurrence rates. Results: Of the 58 patients reviewed, 12 were excluded because there was no culture information available or the culture showed no growth. Of the remaining 46 patients, 33 (72%) were male and 29 (63%) were African American. The mean age was 39.4 ± 16.4 years and the Body Mass Index was 28.4 ± 6.6 kg/m². Culture data revealed mixed aerobic/anaerobic organisms in 17 (37%), mixed aerobic organisms in 15 (32.6%), gram-positive organisms in 9 (19.6%), gram-negative organisms in 2 (4.4%), and other organisms in 3 (6.6%). Twenty-five patients (54.4%) received adequate antibiotic coverage with the remainder inadequately covered. The inadequate antibiotic therapy cohort had a higher re-admission rate for abscess recurrence (n = 6 [28.6%] versus n = 1 [4%]; p = 0.021). More than half were readmitted 30 days or more after the index procedure. There were no differences in length of stay (LOS), intensive care unit LOS, or Charlson Comorbidity Index between the groups. Conclusion: Inadequate antibiotic coverage after I&D of complicated peri-rectal abscess resulted in a six-fold increase in the re-admission rate. A standard oral protocol combining antibiotics covering typical gram-positive, gram-negative, and anaerobic organisms should provide adequate coverage after surgical drainage. Additional prospective studies are needed to elucidate the optimal antibiotic regimen for these patients.

Are Patients with Perforated Peptic Ulcers Who are Negative for Helicobacter pylori at a Greater Risk?

Background: The link between Helicobacter pylori infection and peptic ulceration is well established. Recent studies have reported a decrease of H. pylori-related peptic ulcer disease; Helicobacter pylori eradication is likely the cause of this decrease. We hypothesized that patients with H. pylori-positive perforated peptic ulcer disease (PPUD) requiring surgical intervention had worse outcomes than patients with H. pylori-negative PPUD. Patients and Methods: A prospectively collected Acute and Critical Care Surgery registry spanning the years 2008 to 2015 was searched for patients with PPUD and tested for H. pylori serum immunoglobulin G (IgG) test. Patients were divided into two cohorts: H. pylori positive (HPP) and H. pylori negative (HPN). Demographics, laboratory values, medication history, social history, and esophagogastroduodenoscopy were collected. Student t-test was used for continuous variables and χ² test was used for categorical variables. Linear regression was applied as appropriate. Results: We identified 107 patients diagnosed with PPUD, of whom 79 (74%) patients had H. pylori serum IgG testing. Forty-two (53.2%) tested positive and 37 (46.8%) tested negative. Helicobacter pylori-negative PPUD was more frequent in females (70.27%, p = 0.004), whites (83.78%, p = 0.001) and patients with higher body mass index (BMI) 28.81 ± 8.8 (p = 0.033). The HPN group had a lower serum albumin level (2.97 ± 0.96 vs. 3.86 ± 0.91 p = 0.0001), higher American Society of Anesthesiologists (ASA; 3.11 ± 0.85 vs. 2.60 ± 0.73; p = 0.005), and Charlson comorbidity index (4.81 ± 2.74 vs. 2.98 ± 2.71; p = 0.004). On unadjusted analysis the HPN cohort had a longer hospital length of stay (LOS; 20.20 ± 13.82 vs. 8.48 ± 7.24; p = 0.0001), intensive care unit (ICU) LOS (10.97 ± 11.60 vs. 1.95 ± 4.59; p = 0.0001), increased ventilator days (4.54 ± 6.74 vs. 0.98 ± 2.85; p = 0.004), and higher rates of 30-day re-admission (11; 29.73% vs. 5; 11.91%; p = 0.049). Regression models showed that HPN PPUD patients had longer hospital and ICU LOS by 11 days (p = 0.002) and 8 days (p = 0.002), respectively, compared with HPP PPUD. Conclusion: In contrast to our hypothesis, HPN patients had clinically worse outcomes than HPP patients. These findings may represent a difference in the baseline pathophysiology of the peptic ulcer disease process. Further investigation is warranted.

Early Emergency General Surgery Is Associated with a Higher Incidence of Clostridium difficile Infection

BACKGROUND

Clostridium difficile infection (CDI) is an important surgical complication. Emergency general surgery (EGS) is a developing area of the acute care surgical practice. Few studies evaluating the incidence and risk factors of CDI in this patient population are available.

PATIENTS AND METHODS

A prospectively maintained Acute and Critical Care Surgery registry spanning from 2008 to 2015 was queried for cases of operative EGS with clinical suspicion of CDI post-operatively. Diagnosis of CDI was made using toxin A/B assay in stools. Demographics, co-morbidities, surgical procedures, length of stay (LOS), intensive care unit LOS, antibiotic use, and death were obtained. The patients positive and negative for CDI were compared using chi-squared and Student's t-test. Multi-variable logistic regression was used to determine risk factors for CDI.

RESULTS

A total of 550 patients were identified. The total incidence of CDI was 12.7%. There was no significant difference in demographics between CDI positive and negative patients. Average time to CDI diagnosis was 10.1 ± 8.5 days post-operatively. Patients who received three or more antibiotic classes were at higher risk of CDI developing post-operatively (83% vs. 75%, p = 0.04). The CDI positive patients underwent an EGS significantly earlier than CDI negative patients (0.9 ± 2.3 vs. 3.2 ± 9.2 days, p < 0.001). The most common procedures were partial colectomies (21.4%); small bowel resections/repairs (12.9%); gastric repair for perforated peptic ulcer (10%); skin and soft tissue procedure (7.1%), and laparotomies (5.7%). There was no difference in outcomes between the groups. On linear regression, an EGS performed later after admission was an independent risk factor for lower CDI (OR 0.87; CI 95% [0.79-0.96], p < 0.01).

CONCLUSION

Patients undergoing an early EGS have a high incidence of CDI. The number of antibiotic classes administered post-operatively affects CDI status. Bowel resections appear to be at increased risk for CDI. Clinicians should have a high index of suspicion and low threshold for testing C. difficile in high-risk EGS patients.

Splenic Embolization Decreases Infectious Complications and Resource Utilization Compared to Splenectomy in Severely Injured Patients

Introduction. Increasing use of main coil angioembolization for splenic injury has raised concerns of increased complication rates and resource utilization compared to splenectomy. This study examined complication rates for severely injured patients undergoing splenectomy versus main coil angioembolization. Methods. Demographic data (age, sex, and race), Injury Severity Score (ISS), and splenic injury grade were collected prospectively on all patients admitted to the intensive care unit with blunt splenic injury treated with splenectomy or main coil angioembolization. Outcome measures (transfusion requirements, mechanical ventilation use and duration, mortality, intensive care unit and hospital length of stay, infection rate, and systemic inflammatory response syndrome or SIRS score) were reviewed daily. Results. Of 116 patients reviewed, 65 underwent splenectomy and 51 underwent main coil angioembolization. Groups were comparable for age, sex, race, and mechanism of injury. Splenectomized patients had a higher ISS (41 vs 31) and splenic injury grade (3.7 vs 3.2). The main coil angioembolization group had a lower transfusion requirement, hospital length of stay, incidence of mechanical ventilation, nosocomial infection rate, and SIRS score. Overall, mortality and ventilator days were lower but not statistically significant. Conclusions. Severely injured patients treated with splenectomy had significantly higher infection rates and resource utilization compared to those treated with main coil angioembolization.

Comparison study of acellular dermal matrices in complicated hernia surgery

BACKGROUND

Damage control surgery and management of the open abdomen has led to a significant improvement in survival in trauma and emergency surgical patients. However, subsequent abdominal reconstruction has become a significant challenge. The objective of this study was to compare 2 different acellular dermal matrices in regard to hernia recurrence and complications in patients who present with a large complicated ventral hernia as a result of trauma or emergency surgery.

STUDY DESIGN

A prospective quasi-experimental time-interrupted series design was used to evaluate the incidence of hernia recurrence in trauma/emergency surgery patients who had a ventral hernia repair with a biologic matrix. From January 2005 to December 2007, 55 patients with a complicated ventral hernia were repaired with AlloDerm (Life Cell Corporation). Beginning in February 2008 to January 2010, 40 patients with the same criteria were repaired with FlexHD (Musculoskeletal Transplant Foundation) and followed prospectively over the following year. The primary outcome for this study was hernia recurrence (functional or real) at 1 year. Other outcomes variables included abdominal laxity, seroma formation, and wound or intra-abdominal infection.

RESULTS

There was no significant difference in age, sex, and body mass index between the groups. In addition, there was no significant difference in the mean hernia size and size of the acellular dermis that was inserted. At 1 year postsurgery, all of the AlloDerm patients were diagnosed with recurrence requiring a second formal repair. Eleven patients (31%) whose hernias were repaired with FlexHD were diagnosed with a recurrence requiring a second formal repair.

CONCLUSIONS

FlexHD appears to have reduced the recurrence and laxity rates while maintaining a similar complication profile compared with AlloDerm in trauma/emergency surgery patients with large complicated ventral hernias.

Tight glycemic control in critically injured trauma patients

OBJECTIVES

Evaluate the impact of a tight glucose control (TGC) protocol during the first week of admission in critically injured trauma patients.

METHODS

A prospective quasi-experimental interrupted time-series design was used to evaluate the impact of TGC [24-month preintervention phase (no TGC) vs. 24-month postintervention phase]. Patients were stratified by serum glucose level on day 1 to 7 (low, 0-150 mg/dL; medium-high, 151-219 mg/dL; and high, >/=220 mg/dL), age, gender, and injury severity. Patients were further stratified by pattern of glucose control (all low, all medium high, all high, improving, worsening, highly variable). Outcome was measured by ventilator days, infection, hospital (HLOS) and ICU (ILOS) length of stay, and mortality.

RESULTS

One thousand twenty-one patients were evaluated in the preintervention phase as compared with 1108 patients in the postintervention phase. There was no significant difference in mechanism of injury (83% vs. 84% blunt), gender (74% vs. 73% male), age (44 vs. 43 years), and Injury Severity Score (ISS) (26 vs. 25). The TGC group was more likely to be in the all low and improving pattern of glucose control (P<0.001). The incidence of infection significantly decreased (over the first 2 weeks) from 29% to 21% in the TGC group (P<0.001). Ventilator days (OR=3.9, 1.8, 8.1), ILOS (OR=4.3, 2.1, 7.5), and HLOS (OR=5.5, 2.2, 11) and mortality (OR=1.4, 1.1, 10) were significantly higher in the non-TGC group when controlled for age, ISS, obesity, and diabetes (P<0.01).

CONCLUSION

The positive outcomes associated with the implementation of a TGC protocol necessitates further evaluation in a randomized prospective trial.