Zworth Reading

Sodium Bicarbonate for Acute Metabolic Acidosis in Critically Ill Adults: A Meta-Analysis of Randomized Clinical TrialsLOE 1 (Meta-analysis of RCTs)

Critical Care Medicine

In critically ill adults with acute metabolic acidosis, does sodium bicarbonate compared to placebo reduce mortality or need for RRT?

The teaching I always received in residency was to only give bicarb for severe acidosis (i.e pH < 7) do to risk of paradoxical intracellular and CSF acidosis if a patient can't adequately ventilate their CO2. The argument was that bicarb helped improve the numbers but not the patient. That said ICU almost always wants us to give bicarb.

In this SR, Bicarbonate significantly reduced RRT requirement (RR 0.69, 95% CI 0.61-0.78) with trial sequential analysis confirming firm evidence. Mortality showed non-significant trend toward benefit (RR 0.84, 95% CI 0.55-1.30) but TSA indicates insufficient sample size for conclusions.

Only 4 RCTs with 1,111 patients total—this is a small evidence base for such a common intervention. The RRT reduction is robust and clinically meaningful (NNT ~6-8). The mortality signal is interesting but inconclusive.Heterogeneity in acidosis etiology and severity across trials limits applicability to specific patient subgroups.

Bottom line: Strongest evidence yet that bicarbonate reduces RRT in severe metabolic acidosis. Mortality benefit remains unproven but plausible. For the septic patient with pH <7.2 and AKI, this supports bicarbonate use—not to 'correct the pH' but potentially to avoid dialysis which is certainly a patient-centred outcome. These decisions still need to be made on a case by case basis and keeping in mind the underlying pathophysiology for each patient. 

Raising the Barb: Evolving Practices in Alcohol Withdrawal ManagementKnowledge translation / clinical review

EMOttawa  ·  Mixed—likely synthesizing observational data and expert opinion on phenobarbital protocols

Reviews the growing interest in phenobarbital for alcohol withdrawal, particularly for benzodiazepine-resistant cases. The framing around 269 daily alcohol-related hospitalizations exceeding MI admissions is important. The underlying evidence for phenobarbital protocols remains largely observational, but its use as a second line agent in severe withdrawal is generally accepted and 

Bottom line: Definitely worth reading if you are not familiar with phenobarbital protocols for AWS. The evidence base is still weak, but the practical considerations are well-presented. My current approach and that advocated by METAPHI is to use benzos as first line but if the patient has severe withdrawal symptoms not responding to escalating benzo doses, to give a single dose of IV phenobarbital. For now, I would reserve additional dosing for ICU. 

EM@3AM: Septic AbortionEducational case-based review

emDocs  ·  LOE 5 (Expert opinion / educational content)

Case-based review of septic abortion recognition and management. Classic presentation: first trimester pregnancy, fever, abdominal pain, foul-smelling discharge. High-yield for pattern recognition.

Bottom line: Solid refresher on a diagnosis you can't afford to miss. No new evidence, but the clinical pattern is worth reinforcing.

Clinical Conundrum: Lower GI Bleeding — Who Needs a CTA?Clinical decision-making review

REBEL EM  ·  LOE 3-4 (Observational data synthesis / expert framework)

Practical framework for the ED decision of which lower GI bleeding patients need CT angiography. Reviews the evidence on CTA timing, predictors of active bleeding on imaging, and how CTA guides intervention (IR embolization vs. surgical vs. endoscopic). Covers risk stratification tools and the key question of who can go straight to colonoscopy vs. who needs CTA first.

Bottom line: High-yield for a common ED presentation. Important reminder that if you are imaging LGIB, the test of choice is triple phase CTA and not just standard CT abdomen with contrast. 

How I do it: Managing a Critically Ill Patient with Pulmonary Arterial HypertensionLOE 5 (Expert opinion / narrative review)

Chest  ·  Pulmonary/Critical Care

N/A—expert guidance document

Comprehensive framework for ICU management of decompensated RV failure in PAH: optimize preload (often need diuresis, not fluids), support contractility, reduce afterload, avoid intubation if possible, early ECMO consideration.

The PAH patient in extremis is exactly the scenario where expert guidance matters because RCTs don't exist. The key ED-relevant points: these patients die from RV failure, not the underlying lung disease; fluid boluses can kill them; intubation is extremely high-risk; and early involvement of PAH specialists and ECMO teams is critical. Recognizing the undiagnosed PAH patient is half the battle: think PAH in any young-to-middle-aged patient (especially female) with progressive dyspnea, syncope on exertion, or unexplained RV dilation on echo. Bedside POCUS showing a dilated, hypokinetic RV with septal flattening (D-sign) and small underfilled LV in a dyspneic patient without obvious cause should raise immediate suspicion — even if PAH is not in the chart.

Bottom line: Not evidence-based but practically essential. If you see a known PAH patient in distress, the management is counterintuitive (no fluids, avoid intubation, consider inotropes early). For the undiagnosed patient: RV dilation + septal D-sign + progressive dyspnea, be judicicious with IV fluids.

Should anticoagulants be initiated in patients with sepsis-induced new-onset atrial fibrillation? Best evidence topic report.LOE 4 (Best evidence topic review of observational studies)

Emergency Medicine Journal  ·  Infectious Disease / Cardiology

In patients with sepsis-induced new-onset AF, does initiating therapeutic anticoagulation reduce stroke risk compared to no anticoagulation?

Four observational studies identified. None showed significant stroke reduction with anticoagulation. One large study found a paradoxical increase in stroke with AC. Bleeding risk was not consistently increased. One study reported reduced mortality with AC.

This is a focused best evidence topic review, not a systematic review or meta-analysis. The evidence base is entirely observational with significant heterogeneity. Sepsis-induced AF is likely a different animal from chronic AF: it's often transient, driven by the physiologic stress of sepsis rather than structural atrial disease, and may resolve with source control. The paradoxical stroke increase is probably confounded by indication. Sicker patients with more comorbidities may be more likely to receive AC and also more likely to have embolic events. The key question of whether this AF will recur after sepsis resolves is unanswered.

Bottom line: Current evidence does not support routine anticoagulation for sepsis-induced new-onset AF. Treat the sepsis. If AF persists after recovery, reassess stroke risk with CHA₂DS₂-VASc in the outpatient setting. An RCT is needed — this BET report confirms the uncertainty and the gap.

Coronary microvascular dysfunction and cardiovascular outcomes (Multicenter FLOW-CMD Registry)LOE 3 (Prospective cohort)

Lancet

Why it matters to EPs: Explains why some chest pain patients with 'clean' coronaries still have events. Relevant to risk stratification discussions and understanding the limitations of anatomic-only assessment.

Among 1,003 patients undergoing coronary angiography, microvascular dysfunction (CFR <2.0 and IMR ≥25) was present in 21.5% with obstructive CAD and 9.3% without. At 2 years, those with microvascular dysfunction had nearly double the rate of MACE (HR 1.91, 95% CI 1.22-2.99).

Well-designed prospective registry from South Korea. The composite endpoint mixes hard outcomes (death, MI) with softer ones (revascularization, HF hospitalization). Industry funding from Abbott and Boston Scientific is notable given they make the physiological assessment tools. Generalizability to non-Asian populations is uncertain.

Bottom line: Microvascular dysfunction is real, common, and prognostically important. This won't change your ED workup, but it's useful context to understand that a 'normal' cath doesn't mean zero risk, and why ongoing symptoms deserve follow-up.