David T. Lawrence

Termination of drug-induced torsades de pointes with overdrive pacing

Drug-induced prolongation of the QT interval is frequently encountered after medication overdose. Such toxicity can result in degeneration to torsades de pointes (TdP) and require overdrive pacing. We present 3 cases in which intentional medication overdose resulted in QTc prolongation with subsequent degeneration to TdP. Despite appropriate care, including magnesium therapy, each case required overdrive pacing for resolution of TdP. Although rarely encountered, patients with drug-induced TdP can be successfully managed with overdrive pacing.

A Case of Cyanide Poisoning and the Use of Arterial Blood Gas Analysis to Direct Therapy

Abstract Cyanide poisoning is a difficult diagnosis for health care professionals. Existing reports clearly demonstrate that the initial diagnosis is often missed in surreptitious cases. The signs and symptoms can mimic numerous other disease processes. We report a case in which a suicidal patient ingested cyanide and was found unresponsive by 2 laboratory coworkers. The coworkers employed cardiopulmonary resuscitation with mouth-to-mouth resuscitation. The suicidal patient died shortly after arrival to the hospital, while the 2 coworkers who performed mouth-to-mouth resuscitation presented with signs and symptoms that mimicked early cyanide toxicity but were instead due to acute stress response. An arterial blood gas analysis may help aid in the diagnosis of cyanide toxicity. Electrocardiographic findings in a patient with cyanide poisoning range significantly, depending on the stage of the poisoning.

CHAPTER 4 – Toxin-Induced Neurologic Emergencies

Exposure to toxins may cause several common neurological emergencies, including toxin-induced seizures, acute change in mental status, and muscle weakness (see also specifi c chapters for these problems in the Neurotoxic Syndromes section of this book). When a patient presents with a known or suspected poisoning, knowledge of the potential complications associated with that toxin or toxins will enable the health-care team to clearly manage those poisoned patients. This chapter reviews commonly encountered neurologic emergencies associated with poisonings and reviews the appropriate initial management of the poisoned patient.