Partial
Partial review only. This label is not a full sign-off.
Tricyclic Overdose: ECG Signs and Sodium Bicarbonate
PUBLICATION HOLD. Scoped source/claim review only; no whole-post clinical sign-off, continuous-video/audio review or independently verified native upload identity. Read corrections, source limitations and the per-post readiness record.
ECG markers of risk in tricyclic antidepressant toxicity. Two recorded study references checked; treatment recommendations remain under review.
Review scope
- Clinical evidence complete: no
- Rendered text review complete: no
- Native upload identity verified: no
Remaining priority: Original TOXBASE dose/ventilation/drug-exclusion protocol and full original ECG-risk study texts.
Still unreviewed
- Obtain the actual recorded TOXBASE/UK protocol and verify bicarbonate dose/bolus cap, ventilation, sodium/pH limits and all drug exclusions.
- Read both original study full texts for boundary definitions, ECG technique and cohort applicability; current source records rely on indexed publisher material.
Claim audit
An assessment names one claim. It is not a full sign-off of the post.
qualified — Bicarbonate target and major toxicity mechanisms
Actual CHOP specialist sheet supports pH 7.45–7.55 and QRS/electrolyte monitoring. It gives 1 mEq/kg boluses (max 50 mEq), not the entire recorded 1–2 mmol/kg regimen; protocols differ. TOXBASE itself remains inaccessible/unreviewed.
Qualifications on the reviewed points
- ECG thresholds indicate risk, not guaranteed seizures or arrhythmias.
- Published study boundaries include 100 ms, 160 ms and 3 mm (≥), not strictly greater than.
- pH 7.45–7.55 and response/electrolyte monitoring are supported by the additional CHOP sheet; exact recorded TOXBASE regimen, ventilation instruction and all drug exclusions remain unresolved. Do not combine protocols silently.
References recorded with the episode
Recorded with the episode
Value of the QRS duration versus the serum drug level in predicting seizures and ventricular arrhythmias after an acute overdose of tricyclic antidepressants
1985
DOI 10.1056/NEJM198508223130804
Bibliographic identity and relevant claims checked against official publisher/DOI search-index content; live HTTP reachability not established
Link check recorded
Recorded as supporting
- In the 49-patient cohort, seizures occurred with QRS ≥100 ms; ventricular arrhythmias were observed only with QRS ≥160 ms.
Limits and what this source leaves unreviewed
- Observational cohort, not deterministic thresholds. Does not itself validate bicarbonate dosing or all drug-avoidance advice.
Recorded with the episode
ECG lead aVR versus QRS interval in predicting seizures and arrhythmias in acute tricyclic antidepressant toxicity
1995
DOI 10.1016/S0196-0644(95)70151-6
Open source at annemergmed.com
Bibliographic identity and relevant claims checked against official publisher/DOI search-index content; live HTTP reachability not established
Link check recorded
Recorded as supporting
- Terminal R in aVR ≥3 mm was associated with seizures/arrhythmias in a 79-patient cohort.
Limits and what this source leaves unreviewed
- Risk marker, not certainty; published threshold is ≥3 mm, whereas caption says over 3 mm. TOXBASE recommendations not accessed.
Supporting literature checked separately
Supporting literature checked separately. Not the episode’s recorded source.
Cyclic Antidepressant (TCA) Poisoning — Quick Tox Treatment Tips QT3, updated 16 June 2025
2025
DOI not recorded
Relevant primary full text actually read during final unresolved-group pass; not whole-post verification.
Link check recorded
Recorded as supporting
- Fast sodium-channel blockade, GABA-A antagonism and alpha-1 blockade are described.
- Sodium bicarbonate with QRS and blood-pH response monitoring; target pH 7.45–7.55; monitor Ca, K and Mg.
- Institutional sheet gives 1 mEq/kg boluses, maximum 50 mEq per bolus; norepinephrine, refractory rescue and individualized toxicology advice are discussed.
Limits and what this source leaves unreviewed
- Institutional expert tip sheet explicitly does not establish a standard of care; not the recorded TOXBASE source.
- Its 1 mEq/kg, maximum-50-mEq bolus does not independently validate the entire recorded 1–2 mmol/kg regimen or all drug exclusions.
- Website file path contains 2026, but the document itself states last updated 16 June 2025.
Recorded source note
Stored with the release. This note is not itself a checked reference.
- Boehnert and Lovejoy, NEJM 1985; Liebelt, Ann Emerg Med 1995; TOXBASE/UK poisons guidance.
Historical caption
Audit record of the caption stored with this release. It is not a new endorsement.
Tricyclic Overdose: ECG Signs and Sodium Bicarbonate
Tricyclic overdose kills through sodium channel blockade. A QRS over 100 ms predicts seizures, over 160 ms predicts ventricular arrhythmias, and a terminal R wave over 3 mm in aVR predicts both. Treat with 8.4% sodium bicarbonate 1–2 mmol/kg IV, repeated to narrow the QRS, aiming for arterial pH 7.45–7.55. Use benzodiazepines for seizures and avoid flumazenil, physostigmine and class IA/IC antiarrhythmics. Sources: Boehnert and Lovejoy, NEJM 1985; Liebelt, Ann Emerg Med 1995; TOXBASE/UK poisons guidance.
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