Kooda, Kirstin

Background Chlorhexidine is commonly used in prevention bundles for ventilator-associated pneumonia. Results for use of chlorhexidine in critically ill patients requiring mechanical ventilation via an endotracheal tube are mixed, and data for patients using a tracheostomy are lacking. Objectives To assess the risk for ventilator-associated pneumonia according to chlorhexidine exposure in patients requiring a new tracheostomy for mechanical ventilation. Methods This single-center, retrospective cohort study compared the development of ventilator-associated pneumonia according to chlorhexidine exposure in adult intensive care unit patients requiring new tracheostomy at a large academic medical center. Adults who received a new tracheostomy and required ventilator support for at least 48 hours were included. Patients treated for pneumonia at the time of tracheostomy or who met additional exclusion criteria were excluded. Results Of 235 patients who met the inclusion criteria, 203 received chlorhexidine and 32 did not. The cohort was predominantly White, male, and admitted to a surgical intensive care unit. Incidence of ventilator-associated pneumonia did not differ significantly between patients exposed or not to chlorhexidine (by 30 days, 32.5% vs 35.7%, P = .87). Time to development of ventilator-associated pneumonia also did not differ significantly between patients exposed or not (9 vs 12 days, respectively, P = .34). Conclusions Chlorhexidine exposure was not associated with a difference in the incidence of or time to ventilator-associated pneumonia after new tracheostomy. Further study is needed on the role of chlorhexidine in preventing ventilator-associated pneumonia after a new tracheostomy.

Abstract Background Methicillin-susceptible Staphylococcus aureus bacteremia (MS-SAB) is treated with antistaphylococcal penicillins (ASP) or cefazolin. Altered pharmacokinetics in the setting of hypoalbuminemia may reduce the likelihood of therapeutic success in patients receiving highly protein bound beta-lactams. ASPs and cefazolin are 94% and 80% protein bound, respectively. We assessed the impact of hypoalbuminemia (≤2.5 g/dL) on clinical outcomes in patients with MS-SAB treated with ASPs or cefazolin.Table 1:Unweighted and weighted analysis of full cohort by albumin statusTable 2:Weighted analysis of cefazolin and ASP cohorts by albumin status Methods This single center, retrospective study included adults (≥18 years) admitted with community-acquired MS-SAB between 1/1/2006 and 12/31/2019 who received ASPs or cefazolin and had a serum albumin obtained between the date of first culture positivity and 72 hours of definitive therapy. Exclusion criteria included receipt of ≥5 days of MSSA active empiric therapy prior to definitive, polymicrobial bacteremia, antibiotics for an indication other than MS-SAB, or central nervous system infection. The primary outcome was failure to clear blood cultures within 72 hours of definitive therapy initiation. Propensity score weighting was used to adjust for baseline differences between cohorts. Results 160 patients were included with 61 (38.1%) being hypoalbuminemic (Table 1). In the propensity score weighted analysis, the primary outcome occurred in 37% of patients with an albumin ≤2.5 g/dL vs. 10.2% with an albumin >2.5 g/dL (p< 0.001). This finding was consistent in both ASP and cefazolin subgroups (Table 2). Hospital length of stay was longer in hypoalbuminemic patients but did not represent a statistically significant difference in the weighted overall analysis (15.9 vs. 11.6 days, p=0.8). There was no difference in inpatient mortality in any of the cohorts analyzed. 90-day all-cause mortality was higher in hypoalbuminemic patients only in the cefazolin subgroup analysis (20.7% vs 4.9%, p=0.019). Conclusion The presence of hypoalbuminemia was associated with failure to clear blood cultures within 72 hours of definitive therapy initiation in patients with MS-SAB. While no significant difference in mortality was observed overall, the higher mortality in the cefazolin subgroup warrants further research on the impact of hypoalbuminemia on clinical outcomes in patients with MS-SAB. Disclosures Larry M. Baddour, MD, UpToDate, Inc.: Royalty payments (authorship duties).

Background This study aimed to evaluate outcomes of different antibiotic durations in patients with severe diverticulitis. Methods Initial electronic medical record review identified 2437 adult patients who underwent sigmoid colectomy. Manual chart review identified 133 patients who underwent sigmoid resection and proximal diversion for Hinchey stage 3 or 4 diverticulitis. Patients who received a short antibiotic course (SAC, ≤5 days) were compared with those who received a long antibiotic course (LAC, >5 days). The primary composite outcome included superficial, incisional, organ-space infections or death within 30 days post procedure. Results A total of 53 SAC patients and 55 LAC patients were identified. The composite outcome occurred more frequently in LAC patients than in SAC patients (40% vs 15%; P = .005). Organ-space infection occurred more frequently in LAC patients than in SAC patients (31% vs 13%; P = .04). Conclusions Extended duration of antibiotics after adequate source control does not improve outcomes even in the setting of extensive intra-abdominal contamination.

This study aimed to determine if extended infusion (EI; over > 3 hr) beta-lactam therapy increased IV access requirements compared with traditional dosing (TD; over 30 min). Eighty-six adult ICU patients treated with TD anti-pseudomonal beta-lactams who underwent therapeutic drug monitoring (TDM) were included. Patients who transitioned from TD to EI after TDM (EI group) were matched 1:1 to patients who remained on TD. In the primary analysis, the median (interquartile range) total number of lumens in the 24 hours before TDM compared with the 48 hours after TDM were similar between groups (pre: TD 3 [2–5] vs. EI 4 [3–5]; p = 0.22 and post: TD 3 [2–4] vs. EI 4 [3–5]; p = 0.05). Delivery of beta-lactams via EI was not associated with a need for more IV access. Practical challenges such as access should not limit use of EI beta-lactams when indicated.

ABSTRACT Pneumonia may be caused by a diverse group of microorganisms; however, a microbiologic diagnosis is not universally made. Molecular tests such as the BIOFIRE FILMARRAY Pneumonia Panel (BF-PP) offer the possibility of rapid identification of potential pneumonia pathogens. This retrospective analysis was conducted as a sub-study of a recently published randomized controlled trial. Specimens from patients with suspected pneumonia were tested by the BF-PP, with results compared to cultures. The overall BF-PP positivity rate was 44.8% (252/563), and was higher [64.6% (164/254)] in specimens from patients ultimately diagnosed with pneumonia. Discrepancies between the BF-PP and cultures were most common for Streptococcus pneumoniae , Haemophilus influenzae , Moraxella catarrhalis, and Streptococcus agalactiae . Positive percent agreement (PPA) and negative percent agreement (NPA) between the BF-PP and culture were 91.4% (CI 86.3%–94.9%) and 83.6% (CI 79.5%–87.2%), respectively. For most bacteria, a correlation between high genomic abundance (genomic copies/mL) reported from the BF-PP and culture growth abundance was found. In specimens from patients ultimately diagnosed with pneumonia, clinical consistency—assessed based on whether BF-PP results aligned with associated culture results—was 79.9% and was highest for bronchoalveolar lavage fluid specimens. The BF-PP has reliable analytical performance and offers the potential advantage over conventional cultures of providing higher detection rates and more rapid results. Interestingly, despite the use of this advanced molecular diagnostic tool, one-third of pneumonia cases remained without a microbiologic etiology. IMPORTANCE This study evaluates the BIOFIRE FILMARRAY Pneumonia Panel by comparing its performance to conventional cultures in a real-world patient population (including patients ultimately diagnosed as not having pneumonia) using different types of specimens. Findings show a higher detection rate of microorganisms with the panel compared to cultures, suggesting that this test could aid in tailoring treatments for pneumonia. However, challenges remain and require further study, including distinguishing true pathogens from colonizing microorganisms and determinig why one-third of patients diagnosed with pneumonia still lacked a microbiologic etiology.

Abstract Reducing antimicrobial exposure by limiting the duration of therapy is an effective antimicrobial stewardship strategy. In this article, we describe the impact of modification of the electronic health record to remove default durations of therapy on ambulatory antibiotic prescriptions issued from emergency departments in a large, multicenter health system.

Background: While criteria for the diagnosis of nosocomial pneumonias exist, objective definitions are a challenge and there is no gold standard for diagnosis. We analyzed the impact of the implementation of a logical, consensus-based diagnostic and treatment protocol for managing nosocomial pneumonias in the cardiovascular surgery intensive care unit (CVS-ICU). Methods: We conducted a quasi-experimental, interrupted time series analysis to evaluate the impact of a diagnostic and treatment protocol for nosocomial pneumonias in the CVS-ICU. Impacts were measured relative to patient outcomes, diagnostic processes, and antimicrobial stewardship improvement. Descriptive statistics were used to analyze results. Results: Overall, 35 pre-protocol and 39 post-protocol patients were included. Primary clinical variables suggesting pneumonia in pre- and post-protocol patients were new lung consolidation (50% vs. 71%), new leukocytosis (59% vs. 64%), and positive culture (32% vs. 55%). Appropriate diagnostic testing improved (23% vs. 54%, p = 0.008) after protocol implementation. The proportion of patients meeting the criteria for nosocomial pneumonia (77% vs. 87%) was not statistically significant, though more patients in the post-protocol group met probable diagnostic criteria (51% vs. 77%). Duration of therapy was not significantly different (6 days [IQR = 5.0, 10.0] vs. 7 days [IQR = 6.0, 9.0]). Conclusions: The implementation of a diagnostic and treatment protocol for management of nosocomial pneumonias in the CVS-ICU resulted in improved diagnostic accuracy, advanced antimicrobial and diagnostic stewardship efforts, and laboratory cost savings without an adverse impact on patient-centered outcomes.

OBJECTIVES: Evaluate effectiveness and safety outcomes associated with the use of ketamine for primary analgosedation in the surgical/trauma ICU setting. DESIGN: Retrospective cohort study. SETTING: Academic medical center in Minnesota. PATIENTS: Patients admitted to the surgical ICU between 2015 and 2019 requiring mechanical ventilation and meeting one of three definitions for ketamine primary analgosedation were included: 1) no concomitant opioid infusion, 2) ketamine monotherapy for greater than or equal to 6 hours with subsequent opioid infusion, or 3) ketamine initiated concomitantly or within 4 hours of opioid and total opioid duration less than 4 hours. INTERVENTIONS: None. MEASUREMENTS: Use of ketamine, analgesics, and sedatives were evaluated. Pain, sedation, and delirium assessments immediately before and during ketamine infusion were collected and compared with reported goals. Concomitant analgesics, sedatives, and psychotropics were recorded. Reported failures due to ineffectiveness and toxicity were collected. MAIN RESULTS: Of 164 included patients, 88% never received a concomitant opioid infusion (primary analgosedation definition 1), 12% met alternative criteria for primary analgosedation (definitions 2 and 3). A majority, 68%, were surgical admissions and mean Acute Physiology and Chronic Health Evaluation III score was 90 (± 30). Median mechanical ventilation duration was 2.5 days (1.1–4.5) and ICU length of stay of 4.9 days (3–8). The median ketamine infusion dose and duration were 0.18 mg/kg/hr (0.1–0.3) and 30 hours (15.1–51.8). Concomitant infusions of propofol and dexmedetomidine were administered in 49% and 29% of patients, respectively. During ketamine infusion, the median percent of total pain scores at goal was 62% (33–96%), while 64% (37–91%) of Richmond Agitation Sedation Scale scores were at goal, and 47% of patients were Confusion Assessment Method-ICU positive during the ketamine infusion. Hallucinations were documented in 14% of patients and ketamine failure occurred in 11% of patients. CONCLUSIONS: Ketamine may be an effective primary analgosedation option in intubated surgical ICU patients, but prospective randomized studies are needed to evaluate this strategy.