Selection bias in estimating the relationship between prolonged ED boarding and mortality in emergency critical care patients.

OBJECTIVES: Studies have found that prolonged boarding time for intensive care unit (ICU) patients in the emergency department (ED) is associated with higher in-hospital mortality. However, these studies introduced selection bias by excluding patients with ICU admission orders who were downgraded and never arrived in the ICU. Consequently, they may overestimate mortality in prolonged ED boarders. METHODS: This was a retrospective cohort study at a single center covering the period from August 14, 2015 to August 13, 2019. Adult ED patients with medical ICU admission orders and at least 6 hours of subsequent critical care in either the ED or the ICU were included. Patients were classified as having either prolonged (>6 hours) or non-prolonged (≤6 hours) ED boarding. Downgraded patients were identified, and mortality was compared, both including and excluding downgraded patients. RESULTS: Of 1862 patients, 612 (32.9%) had prolonged boarding; at 6 hours after ICU admission order entry, they were still in the ED. The remaining 1250 (67.1%) had non-prolonged boarding; at 6 hours after the ICU admission order entry, they were already in the ICU. In-hospital mortality in the non-prolonged boarding group was 18.9%. In the prolonged boarding group, 296 (48.4%) patients were downgraded in the ED and never arrived in the ICU. Including these ED downgrades, the mortality in the prolonged boarding group was 13.4% (risk difference -5.5%, 95% confidence interval [CI] -8.9% to -2.0%, P = 0.0031). When we excluded downgrades, the mortality in the prolonged boarding group increased to 17.4% (risk difference -1.5%, 95% CI -6.2% to 3.2%, P = 0.5720). The lower mortality in the prolonged group was attributable to lower severity of illness (mean emergency critical care SOFA [eccSOFA] difference: -0.8, 95% CI -1.1 to -0.4, P < 0.0001). CONCLUSIONS: Excluding critical care patients who were downgraded in the ED leads to selection bias and overestimation of mortality among prolonged ED boarders.

The Utility of Computed Tomography Angiogram in Patients with Mild Traumatic Subarachnoid Hemorrhage.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) and traumatic subarachnoid hemorrhage (tSAH) differ significantly in their mortality and management. Although computed tomography angiography (CTA) is critical to guide timely interventions in aSAH, it lacks recognized benefit in assessing tSAH. Despite this, CTA commonly is included in tSAH evaluation. OBJECTIVE: Determine if any clinically significant cerebral aneurysms are identified on CTA in emergency department (ED) patients with a tSAH. METHODS: Retrospective observational study of consecutive blunt head trauma patients ages ≥ 16 years with Glasgow Coma Scale score (GCS) ≥ 13 who presented to an academic ED (100,000 annual visits) over a 7-year period. Those included had a CT-diagnosed SAH and underwent head CTA. The primary endpoint was the detection of any clinically significant brain aneurysms. RESULTS: There were 297 patients that met the inclusion criteria. Twenty-six patients (8.8%) had an incidental aneurysm discovered; one underwent elective outpatient intervention. Aneurysm-positive patients were more likely to be female (69.2% vs. 46.9%, p = 0.003), age 60 years or older (80.8% vs. 52.4%, p = 0.005), and be on anticoagulation (42.3% vs. 28.0%, p = 0.03). There were no differences between the aneurysm-positive and -negative patients with respect to GCS, history of hypertension, or mechanism of injury. CONCLUSIONS: In this 7-year retrospective chart review, CTA in patients with tSAH and GCS ≥ 13 did not reveal any clinically relevant cerebral aneurysms. One incidental aneurysm later underwent outpatient neurovascular intervention. In the absence of specific clinical concerns, CTA has minimal value in well-appearing patients with a tSAH.

Is novel coronavirus 2019 reinfection possible? Interpreting dynamic SARS-CoV-2 test results.

Since December 2019, COVID-19, the clinical syndrome associated with SARS-CoV-2 infection, has infected more than 6.2 million people and brought the function of the global community to a halt. As the number of patients recovered from COVID-19 rises and the world transitions toward reopening, the question of acquired immunity versus the possibility of reinfection are critical to anticipating future viral spread. Here, we present a case of a patient previously recovered from COVID-19 who re-presents with new respiratory, radiographical, laboratory, and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) findings concerning for possible re-infection. We review this case in the context of the evolving discussion and theories surrounding dynamic RT-PCR results, prolonged viral shedding, and the possibility of developed immunity. Understanding how to interpret dynamic and late-positive SARS-CoV-2 RT-PCR results after primary infection will be critical for understanding disease prevalence and spread among communities worldwide.