Can we really make catheter-associated urinary tract infections a never event? A level 1 trauma center's experience with prophylactic antibiotic bladder irrigation. Rieger RM, Bonnin SS, Hopp MJ, Low TM, Villa DC, Coates SL, Chapple KM, Soe-Lin H, Weinberg JA. J Trauma Acute Care Surg. 2022 Nov 1;93(5):627-631.
According to the Centers for Medicare and Medicaid Services, catheter-associated urinary tract infections (CAUTIs) are one of 8 core hospital-acquired “Never Events”, and as such are one of the more vigilantly tracked quality measures in current medical practice. The majority of prevention strategies in practice today are centered around early removal of urinary catheters, however this is often not a feasible option in many traumatically injured patients for a variety of reasons. In an attempt to decrease or eliminate the incidence of CAUTI in patients not amenable to early catheter removal, the authors of this study trialed a strategy of prophylactic antibiotic bladder irrigation and compared it with retrospective data at their ACS-verified Level 1 trauma center.
Beginning in 2021, select traumatically-injured patients deemed to require prolonged urinary catheterization underwent gentamicin bladder catheter irrigation (GBCI) twice daily for the duration of their time with a urinary catheter, as a strategy to prevent CAUTI. This involved the instillation of 14.4 mg of gentamicin in 30 mL of 0.9% normal saline via the catheter’s injection port, clamping of the catheter for 1 hour, followed by unclamping and drainage of the catheter. These patients were then compared retrospectively with other traumatically injured patients requiring urinary catheterization of 3 days or greater who did not receive GBCI. Charts of both groups were compared for a number of factors to include patient demographics, mechanism of injury, injury severity score, Glasgow Coma Scale (GCS) score, hospital length of stay, and intensive care unit length of stay. The primary outcome measure was CAUTI incidence rate per 1,000 catheter days. Patients with bladder injuries were excluded from study. Of note, the calculated cost of a single dose of gentamicin infused bladder irrigation solution was $1.45 when prepared in bulk.
Over a 23-month study period, there were 342 patients who required urinary catheterization of 3 or more days duration. 86 patients (25%) underwent GBCI, while the remaining 256 (75%) did not. The groups did not differ statistically in terms of age, sex, race, ethnicity, or mechanism of injury, though the GBCI cohort did have a higher injury severity score and was less likely to have a GCS of 15 on admission. In addition to elevated injury severity score, the GBCI group was also more likely to be admitted to the intensive care unit and had greater lengths of stay for both the intensive care unit and the admission at large.
The 86 patients of the GBCI group had zero CAUTIs over 939 catheterized days, as compared with 9 incidences of CAUTI in the 256 patients of the control group over 2,114 catheterized days. There were no observed adverse events associated with gentamicin bladder irrigation. This study has a number of limitations which are readily acknowledged by the authors (Retrospective nature, single-site, non-randomization, etc.), and they are quick to point out that widespread adoption of GBCI should not be universally enacted based solely on the findings of this single study. However, they have done an admirable job demonstrating that a relatively inexpensive therapy with no observable adverse effect had a clear associated with decreased rates of CAUTI, and are now planning a double-blinded randomized control trial to investigate the potential of GBCI in a more rigorous manner.
Excluding Hollow Viscus Injury for Abdominal Seat Belt Sign Using Computed Tomography. Delaplain PT, Tay-Lasso E, Biffl WL, et al. JAMA Surg. 2022;157(9):771–778.
The presence of an abdominal seatbelt sign (SBS) has historically mandated admission and observation to rule out hollow viscous injury (HVI), regardless of computed tomography (CT) findings. This practice has persisted despite significant improvement in the diagnostic accuracy of CT imaging. The purpose of this study was to obtain data from multiple trauma centers to evaluate whether a negative CT scan can safely predict the absence of HVI in the setting of an abdominal SBS.
The authors begin by discussing the origins of the practice wherein abdominal SBS required admission and observation, based on concerns about the diagnostic accuracy of computed tomography (CT) imaging and the previously quoted strong of association between abdominal SBS and HVI. They describe how both those recommendations and concerns predate the widespread use of multi-slice CT scanning, and how incidences of HVI with abdominal SBS reported in prior studies may have been related to differences in safety between 2-point and modern 3-point restraints. They acknowledge that while multiple studies in recent literature have challenged the notion of limitations of CT in blunt abdominal trauma and abdominal SBS, these findings were limited to single-institution studies, thereby calling their generalizability into question.
In this study, the authors prospectively collected data from adult patients (age ≥18 years) across 9 trauma centers with trauma and an abdominal SBS (as identified per the discretion of the treatment teams) who underwent a CT scan of the abdomen and pelvis with intravenous contrast from August 2020 to October 2021. Data collected by the authors included vital signs (initial heart rate, maximum heart rate in 24 hours, initial temperature, maximum temperature in 24 hours [considered febrile at >38° C], initial systolic blood pressure), initial and repeated test results for white blood cell count and serum lactate, abdominal examination, and results of a Focused Assessment With Sonography for Trauma (FAST) examination and CT scan of the abdomen and pelvis. The data for each CT scan included abdominal wall soft tissue contusion, free fluid, bowel wall thickening, mesenteric stranding, mesenteric hematoma, bowel dilatation, pneumatosis, and pneumoperitoneum. A negative CT was defined as the absence of any of these 8 findings. Details of any abdominal operation were collected, including whether an HVI was suspected preoperatively, the location and severity of HVI (full thickness versus partial thickness), and any interventions. The primary outcome was HVI, defined as the presence of an enteric injury (full or partial thickness) identified during operative exploration. Secondary outcome data collected included mortality, length of stay, intensive care unit (ICU) length of stay, ventilator days, packed red blood cell transfusions, post-discharge presentation to the emergency department, and hospital readmission. If a patient did not undergo an operation, they were considered negative for HVI.
The authors found that, among a total of 754 patients with abdominal SBS, the prevalence of HVI was 9.2% (n = 69), with only 1 patient with HVI (0.1%) having a negative CT (none of the 8 a priori CT findings). On bivariate analysis comparing patients with and without HVI, the individual CT scan finding that was most strongly associated with the presence of HVI was the presence of free fluid, with a more than 40-fold increase in the likelihood of HVI (odds ratio [OR], 42.68; 95%CI, 20.48-88.94; P < .001). Free fluid was also the most common finding in patients with HVI. The presence of free fluid also served as the most effective binary classifier for presence of HVI (area under the receiver operator characteristic curve [AUC], 0.87; 95%CI, 0.83-0.91). There was also an association between a negative CT scan and the absence of HVI (OR, 41.09; 95%CI, 9.01-727.69; P < .001; AUC, 0.68; 95%CI, 0.66-0.70). The authors acknowledged and provided data to support the significance of clinical parameters (heart rate, blood pressure, fever, higher initial lactate and white blood cell count, and abdominal examination), thereby reinforcing the notion that a wide constellation of findings may suggest HVI.
The authors concluded that operative HVI is exceedingly low in the presence of a normal CT scan in agreement with good clinical judgment. This study lends credence to a shift away from historic and current practice, such that discharge can be safely considered for patients with abdominal SBS alone with a negative high-quality CT scan, in lieu of mandated admission in the absence of other concerning findings. The authors also cite that that choosing to discharge patients with a normal CT could result in cost savings of approximately $2000 to $8000 for each avoided admission; thereby avoiding unnecessary admission and associated health care expenditures.