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Cannabis hyperemesis syndrome is characterized by bouts of protracted vomiting in regular users of cannabis. We wondered whether this poorly understood condition is idiosyncratic, like motion sickness or hyperemesis gravidarum, or the predictable dose-response effect of prolonged heavy use.
Adults with an emergency department visit diagnosed as cannabis hyperemesis syndrome, near-daily use of cannabis for ≥6 months, and ≥2 episodes of severe vomiting in the previous year were age- and sex-matched to two control groups: RU controls (recreational users without vomiting), and ED controls (patients in the emergency department for an unrelated condition). Δ9-Tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol, and 11-nor-9-carboxy-THC concentrations in scalp hair were compared for subjects with positive urine THC.
We obtained satisfactory hair samples from 46 subjects with positive urine THC: 16 cases (age 26.8 ± 9.2 years; 69% male), 16 RU controls and 14 ED controls. Hair cannabinoid concentrations were similar between all three groups (e.g. cases THC 220 [median; IQR 100,730] pg/mg hair, RU controls 150 [71,320] and ED controls 270 [120,560]). Only the THC:CBN ratio was different between groups, with a 2.6-fold (95%CI 1.3,5.7) lower age- and sex-adjusted ratio in cases than RU controls. Hair cannabidiol concentrations were often unquantifiably low in all subjects.
Similar hair cannabinoid concentrations in recreational users with and without hyperemesis suggest that heavy use is necessary but not sufficient for hyperemesis cannabis. Our results underline the high prevalence of chronic heavy cannabis use in emergency department patients and our limited understanding of this plant's adverse effects.
Emergency department (ED) access block, the inability to provide timely care for high acuity patients, is the leading safety concern in First World EDs. The main cause of ED access block is hospital access block with prolonged boarding of inpatients in emergency stretchers. Cumulative emergency access gap, the product of the number of arriving high acuity patients and their average delay to reach a care space, is a novel access measure that provides a facility-level estimate of total emergency care delays. Many health leaders believe these delays are too large to be solved without substantial increases in hospital capacity. Our objective was to quantify cumulative emergency access blocks (the problem) as a fraction of inpatient capacity (the potential solution) at a large sample of Canadian hospitals.
In this cross-sectional study, we collated 2015 administrative data from 25 Canadian hospitals summarizing patient inflow and delays to ED care space. Cumulative access gap for high acuity patients was calculated by multiplying the number of Canadian Triage Acuity Scale (CTAS) 1-3 patients by their average delay to reach a care space. We compared cumulative ED access gap to available inpatient bed hours to estimate fractional access gap.
Study sites included 16 tertiary and 9 community EDs in 12 cities, representing 1.79 million patient visits. Median ED census (interquartile range) was 66,300 visits per year (58,700-80,600). High acuity patients accounted for 70.7% of visits (60.9%-79.0%). The mean (SD) cumulative ED access gap was 46,000 stretcher hours per site per year (± 19,900), which was 1.14% (± 0.45%) of inpatient capacity.
ED access gaps are large and jeopardize care for high acuity patients, but they are small relative to hospital operating capacity. If access block were viewed as a “whole hospital” problem, capacity or efficiency improvements in the range of 1% to 3% could profoundly mitigate emergency care delays.
Important questions remain regarding how best to monitor patients during procedural sedation and analgesia (PSA). Capnometry can detect hypoventilation and apnea, yet it is rarely used in emergency patients. Even the routine practice of performing preoxygenation in low-risk patients is controversial, as supplementary oxygen can delay the detection of respiratory depression by pulse oximetry. The purpose of this study was to determine whether the capnometer or the pulse oximeter would first detect respiratory events in adults breathing room air.
During a randomized clinical trial comparing fentanyl with low-dose ketamine for PSA with titrated propofol, patients were monitored using pulse oximetry and continuous oral–nasal sampled capnography. Supplemental oxygen was administered only for oxygen desaturation. Sedating physicians identified prespecified respiratory events, including hypoventilation (end-tidal carbon dioxide > 50 mm Hg, rise of 10 mm Hg from baseline or loss of waveform) and oxygen desaturation (pulse oximetry < 92%). These events and their timing were corroborated by memory data retrieved from the monitors.
Of 63 patients enrolled, 57% (36) developed brief oxygen desaturation at some point during the sedation. All responded to oxygen, stimulation or interruption of propofol. Measurements of end-tidal carbon dioxide varied substantially between and within patients before study intervention. Hypoventilation (19 patients, 30%) was only weakly associated with oxygen desaturation (crude odds ratio 1.4 [95% confidence interval 0.47 to 4.3]), and preceded oxygen desaturation in none of the 12 patients in whom both events occurred (median lag 1:50 m:ss [interquartile range 0:01 to 3:24 m:ss]).
During PSA in adults breathing room air, desaturation detectable by pulse oximeter usually occurs before overt changes in capnometry are identified.
Measurement of the serum B-type natriuretic peptide (BNP) level and more recently its precursor, N-terminal proBNP (NT-proBNP), has been advocated to facilitate the diagnosis of heart failure in the emergency department (ED). We sought to determine the potential impact of adding NT-proBNP testing to the routine evaluation of emergency patients with acute dyspnea.
This prospective cohort study enrolled a convenience sample of acutely dyspneic patients at a tertiary care ED. We excluded trauma patients and those under 30 years of age. Patients underwent standard evaluation, including radiography when indicated. At the point of final diagnosis and blinded to the NT-proBNP result, physicians documented the likelihood that heart failure accounted for the patient's acute dyspnea on a 7-point Likert scale, the data from which was subsequently collapsed to 3 categories for analysis purposes. The primary outcome was the agreement between clinical impression and the NT-proBNP assay classified using manufacturer-recommended, age-specific cut-offs. Newly proposed cut-offs from a recent study were also evaluated.
One hundred and twenty-nine patients making 139 ED visits were enrolled (median age 76 years; 59% admitted). The serum NT-proBNP assay was positive in 119 (86%, 95% confidence interval [CI] 80%–91%) cases, including 75% (43/57, 95% CI 62%–86%) of the cases that the treating physician felt were not caused by heart failure, and 86% (25/29, 95% CI 68%–96%) where the treating physician was unsure. The median NT-proBNP concentration was higher in patients clinically believed to have heart failure rather than pneumonia or chronic obstructive pulmonary disease; however, the ranges of these values overlapped extensively (median 4361 pg/mL; interquartile range [IQR] 2386–10877 v. 1651 pg/mL; IQR 370–4745, respectively).
There is high discordance between the clinical impression of treating physicians and NT-proBNP concentrations, notably in patients who are believed not to have heart failure. Although the reference standard of ED diagnosis is imperfect, the broad overlap in NT-proBNP concentrations suggests poor specificity in this target patient population. The introduction of routine ED NT-proBNP testing using the current cut-offs would be expected to result in substantial indirect costs from further diagnostic testing. It remains unclear whether the introduction of this diagnostic test would have a positive impact on clinically relevant patient outcomes.
Drug abuse is a frequent factor in emergency department (ED) visits. Although commonly performed, qualitative testing of urine for drugs of abuse (u-DOA) is inherently limited in its ability to establish the identity, timing or dose of substances used. Previous studies have demonstrated these limitations, but their designs cannot be used to determine whether the results of u-DOA tests affect physicians’ patient care decisions. Our objective was to determine the impact of u-DOA testing on the care of patients who present to the ED.
All adults 18 years of age or older who had u-DOA testing in 2 urban teaching EDs were eligible. Victims of vehicular trauma or sexual assault were excluded. Just prior to communicating the results of u-DOA testing for a patient, an investigator interviewed the ordering physician or consultant physician about the patient care plans for that patient. Test results were then revealed, and the questions immediately repeated. This design isolated the impact of knowledge of u-DOA test results on physicians’ patient care decisions. Any intended changes in patient care plans reported by the interviewed physician were compared to a priori criteria for substantive change and then subsequently reviewed by an independent expert to determine whether that change was justified.
Of the 110 u-DOA test results studied and the resultant 133 opportunities to influence physician management plans, there were 4 reported changes in management. One management change was judged to be substantive, but none of the 4 reported changes were considered by the independent expert reviewer to be justified. Urine-DOA testing thus led to a justified change in management in 0/133 instances (95% confidence interval 0%–2.3%).
Urine-DOA is rarely helpful in guiding patient care decisions in the ED. The results of this study call into question the need for this test in the ED setting.