[Clinical reasoning and simulation: facilitating hypothesis prioritization using simulated patients. Data from quantitative research]. / Raisonnement clinique et simulation : faciliter la priorisation d'hypothèses grâce aux patients simulés. Données d'une recherche quantitative.

Background: Prioritizing diagnostic hypotheses can be difficult for novice medical students given their limited clinical exposure. Simulated clinical reasoning (CR) clinics allow students to practice focused histories with a simulated patient (SP). The delivery of clinical data by SPs can influence hypothesis generation. Objective: This pilot study seeks to test whether the transmission of key elements through SP acting influences CR prioritization among medical students. Method: The diagnostic hypotheses of two cohorts of students of the same academic level were compared following a virtual interview with an SP. The SPs in the experimental group were given a targeted script and briefing on key elements while the SPs in the control group were given a traditional script and briefing. The difference between the distributions of frequencies of the hypotheses of the two groups was determined using the chi-square calculation. Results: The students in the experimental group prioritized expert-validated hypotheses more than those in the control group. The control group showed greater variability in their diagnostic choices. Conclusion: Targeting the delivery of key elements by SPs could be a way to help novice medical students prioritize their diagnostic hypotheses. Simulated CR clinics therefore become a space for learning about CR in the absence of clinical exposure. The risk of inducing premature closure of clinical reasoning needs further research.

Effect of Moderate vs Mild Therapeutic Hypothermia on Mortality and Neurologic Outcomes in Comatose Survivors of Out-of-Hospital Cardiac Arrest: The CAPITAL CHILL Randomized Clinical Trial.

Importance: Comatose survivors of out-of-hospital cardiac arrest experience high rates of death and severe neurologic injury. Current guidelines recommend targeted temperature management at 32 °C to 36 °C for 24 hours. However, small studies suggest a potential benefit of targeting lower body temperatures. Objective: To determine whether moderate hypothermia (31 °C), compared with mild hypothermia (34 °C), improves clinical outcomes in comatose survivors of out-of-hospital cardiac arrest. Design, Setting, and Participants: Single-center, double-blind, randomized, clinical superiority trial carried out in a tertiary cardiac care center in eastern Ontario, Canada. A total of 389 patients with out-of-hospital cardiac arrest were enrolled between August 4, 2013, and March 20, 2020, with final follow-up on October 15, 2020. Interventions: Patients were randomly assigned to temperature management with a target body temperature of 31 °C (n = 193) or 34 °C (n = 196) for a period of 24 hours. Main Outcomes and Measures: The primary outcome was all-cause mortality or poor neurologic outcome at 180 days. Neurologic outcome was assessed using the Disability Rating Scale, with poor neurologic outcome defined as a score greater than 5 (range, 0-29, with 29 being the worst outcome [vegetative state]). There were 19 secondary outcomes, including mortality at 180 days and length of stay in the intensive care unit. Results: Among 367 patients included in the primary analysis (mean age, 61 years; 69 women [19%]), 366 (99.7%) completed the trial. The primary outcome occurred in 89 of 184 patients (48.4%) in the 31 °C group and in 83 of 183 patients (45.4%) in the 34 °C group (risk difference, 3.0% [95% CI, 7.2%-13.2%]; relative risk, 1.07 [95% CI, 0.86-1.33]; P = .56). Of the 19 secondary outcomes, 18 were not statistically significant. Mortality at 180 days was 43.5% and 41.0% in patients treated with a target temperature of 31 °C and 34 °C, respectively (P = .63). The median length of stay in the intensive care unit was longer in the 31 °C group (10 vs 7 days; P = .004). Among adverse events in the 31 °C group vs the 34 °C group, deep vein thrombosis occurred in 11.4% vs 10.9% and thrombus in the inferior vena cava occurred in 3.8% and 7.7%, respectively. Conclusions and Relevance: In comatose survivors of out-of-hospital cardiac arrest, a target temperature of 31 °C did not significantly reduce the rate of death or poor neurologic outcome at 180 days compared with a target temperature of 34 °C. However, the study may have been underpowered to detect a clinically important difference. Trial Registration: ClinicalTrials.gov Identifier: NCT02011568.

Multidisciplinary Code Shock Team in Cardiogenic Shock: A Canadian Centre Experience.

BACKGROUND: Cardiogenic shock (CS) is associated with high mortality. We report on a "Shock Team" approach of combined interdisciplinary expertise for decision making, expedited assessment, and treatment. METHODS: We reviewed 100 patients admitted in CS over 52 months. Patients managed under a Code Shock Team protocol (n = 64, treatment) from 2016 to 2019 were compared with standard care (n = 36, control) from 2015 to 2016. The cohort was predominantly male (78% treatment, 67% control) with a median age of 55 years (interquartile range [IQR], 43-64) for treatment vs 64 years (IQR, 48-69) for control (P = 0.01). New heart failure was more common in the treatment group: 61% vs 36%, P = 0.02. Acute myocardial infarction comprised 13% of patients in CS. There were no significant differences between treatment and control in markers of clinical acuity, including median left ventricular ejection fraction (18% vs 20%), prevalence of moderate-severe right ventricular dysfunction (64% vs 56%), median peak serum lactate (5.3 vs 4.7 mmol/L), acute kidney injury (70% vs 75%), or acute liver injury (50% vs 31%). Inotropes, dialysis, and invasive ventilation were required in 92%, 33%, and 66% of patients, respectively. Temporary mechanical circulatory support was used in 45% of treatment and 28% of control patients (P = 0.08). There were no significant differences in median hospital length of stay (17.5 days), 30-day survival (71%), or survival to hospital discharge (66%). Over 240 days (IQR, 14,847) of median follow-up, survival was 67% for treatment vs 42% for control (hazard ratio, 0.53; 95% confidence interval, 0.28-0.99; P = 0.03). CONCLUSION: A multidisciplinary Code Shock Team approach for CS is feasible and may be associated with improved long-term survival.

CONTEXTE: Le choc cardiogénique (CC) est associé à une mortalité élevée. Nous décrivons une approche où la prise de décision, l'évaluation rapide des cas et le traitement sont confiés à une « équipe de choc ¼ interdisciplinaire. MÉTHODOLOGIE: Nous avons examiné les cas de 100 patients hospitalisés en raison d'un CC sur une période de 52 mois. Les patients pris en charge par une équipe interdisciplinaire selon un protocole d'intervention déclenché par un code-choc (n = 64, groupe traité) de 2016 à 2019 ont été comparés à des patients ayant reçu des soins courants (n = 36, groupe témoin) de 2015 à 2016. Les patients de la cohorte étaient majoritairement de sexe masculin (78 % dans le groupe traité, 67 % dans le groupe témoin) et l'âge médian était de 55 ans (intervalle interquartile [IIQ] : 43-64) au sein du groupe traité par rapport à 64 ans (IIQ : 48-69) au sein du groupe témoin (p = 0,01). Les nouveaux cas d'insuffisance cardiaque étaient plus fréquents dans le groupe traité : 61 % vs 36 % (p = 0,02). Les patients hospitalisés en raison d'un CC avaient subi un infarctus aigu du myocarde dans 13 % des cas. Aucune différence significative n'a été relevée entre le groupe traité et le groupe témoin au chapitre des marqueurs d'acuité clinique, y compris la fraction médiane d'éjection ventriculaire gauche (18 % vs 20 %), la prévalence d'une dysfonction modérée ou sévère du ventricule droit (64 % vs 56 %), la concentration maximale médiane de lactate sérique (5,3 vs 4,7 mmol/l), l'insuffisance rénale aiguë (70 % vs 75 %) ou l'insuffisance hépatique aiguë (50 % vs 31 %). L'administration d'inotropes, la dialyse et la ventilation effractive ont été nécessaires chez 92 %, 33 % et 66 % des patients, respectivement. Une assistance circulatoire mécanique temporaire a été utilisée chez 45 % des patients du groupe traité et 28 % des patients du groupe témoin (p = 0,08). Aucune différence significative n'a été notée en ce qui concerne la durée médiane des hospitalisations (17,5 jours), la survie à 30 jours (71 %) ou la survie à la sortie de l'hôpital (66 %). Au cours d'une période de suivi médiane de 240 jours (IIQ : 14 847), le taux de survie était de 67 % dans le groupe traité vs 42 % dans le groupe témoin (rapport des risques instantanés : 0,53; intervalle de confiance à 95 % : 0,28-0,99; p = 0,03). CONCLUSION: Dans les cas de CC, l'intervention d'une équipe interdisciplinaire déclenchée par un code-choc est réalisable et pourrait être associée à une amélioration de la survie à long terme.

The Impact of Preoperative Risk on the Association between Hypotension and Mortality after Cardiac Surgery: An Observational Study.

BACKGROUND: Despite steady improvements in cardiac surgery-related outcomes, our understanding of the physiologic mechanisms leading to perioperative mortality remains incomplete. Intraoperative hypotension is an important risk factor for mortality after noncardiac surgery but remains relatively unexplored in the context of cardiac surgery. We examined whether the association between intraoperative hypotension and in-hospital mortality varied by patient and procedure characteristics, as defined by the validated Cardiac Anesthesia Risk Evaluation (CARE) mortality risk score. METHODS: We conducted a retrospective cohort study of consecutive adult patients who underwent cardiac surgery requiring cardiopulmonary bypass (CPB) from November 2009-March 2015. Those who underwent off-pump, thoracic aorta, transplant and ventricular assist device procedures were excluded. The primary outcome was in-hospital mortality. Hypotension was categorized by mean arterial pressure (MAP) of <55 and between 55-64 mmHg before, during and after CPB. The relationship between hypotension and death was modeled using multivariable logistic regression in the intermediate and high-risk groups. RESULTS: Among 6627 included patients, 131 (2%) died in-hospital. In-hospital mortality in patients with CARE scores of 1, 2, 3, 4 and 5 was 0 (0%), 7 (0.3%), 35 (1.3%), 41 (4.6%) and 48 (13.6%), respectively. In the intermediate-risk group (CARE = 3-4), MAP < 65 mmHg post-CPB was associated with increased odds of death in a dose-dependent fashion (adjusted OR 1.30, 95% CI 1.13-1.49, per 10 min exposure to MAP < 55 mmHg, p = 0.002; adjusted OR 1.18 [1.07-1.30] per 10 min exposure to MAP 55-64 mmHg, p = 0.001). We did not observe an association between hypotension and mortality in the high-risk group (CARE = 5). CONCLUSIONS: Post-CPB hypotension is a potentially modifiable risk factor for mortality in intermediate-risk patients. Our findings provide impetus for clinical trials to determine if hemodynamic goal-directed therapies could improve survival in these patients.

A historical overview of bacteriophage therapy as an alternative to antibiotics for the treatment of bacterial pathogens.

The seemingly inexorable spread of antibiotic resistance genes among microbial pathogens now threatens the long-term viability of our current antimicrobial therapy to treat severe bacterial infections such as sepsis. Antibiotic resistance is reaching a crisis situation in some bacterial pathogens where few therapeutic alternatives remain and pan-resistant strains are becoming more prevalent. Non-antibiotic therapies to treat bacterial infections are now under serious consideration and one possible option is the therapeutic use of specific phage particles that target bacterial pathogens. Bacteriophage therapy has essentially been re-discovered by modern medicine after widespread use of phage therapy in the pre-antibiotic era lost favor, at least in Western countries, after the introduction of antibiotics. We review the current therapeutic rationale and clinical experience with phage therapy as a treatment for invasive bacterial infection as novel alternative to antimicrobial chemotherapy.

Tako-tsubo syndrome following nortriptyline overdose.

BACKGROUND: Tako-tsubo syndrome (TTS) refers to the apical ballooning of the left ventricle observed when angiographic ventriculography is performed in patients presenting with electrocardiographic changes suggestive of acute coronary syndrome (new transient ST-segment deviation (>0.05 mV) or T-wave inversion (>0.2 mV)), mild elevation of cardiac markers, but normal coronary arteries at the angiogram. CASE REPORT: A 54-year-old woman developed the characteristic features of TTS 44 hours following nortriptyline overdose. The admission ECG showed increased QRS duration rapidly reversible after sodium bicarbonate infusion. There was a minimal increase in troponin I level. The ECG performed at the time of chest pain revealed deeply negative T waves in leads I, II, III, aVF, V1 to V6 and remained abnormal at 5 weeks follow-up. In contrast, a complete recovery of left ventricular function was observed within one week. DISCUSSION: The pathophysiology of TTS, a variant of myocardial stunning, is still incompletely understood but could be related to sympathetic overstimulation. The possibility of TTS following toxic exposure is discussed.