Anticholinergic syndrome induced by toxic plants

A sabbath in the emergency room or a case of anticholinergic toxicity?

We report the case of a 32-year-old Italian man admitted to our emergency room for visual disturbances with blurred vision, anisocoria and temporal headache suddenly occurred in absence of other neurological symptoms. A diagnosis of Datura stramoniuminduced anticholinergic toxicity was done. With our work, we want to highlight the importance of a meticulous clinical examination, including papillary diameter and reflexes, combined with a detailed history of the patient in the emergency room. Anticholinergic toxicity is a medical emergency. The diagnosis is always clinical, and it can represent a challenge for the emergency clinicians because it can mimic several neurological diseases, including acute stroke and seizures, but early diagnosis is crucial to avoid severe complications and management errors.

Adrenaline is effective in reversing the inadequate heart rate response in atropine treated organophosphorus and carbamate poisoning

BACKGROUND

In acute organophosphorus (OP) or carbamate poisoning, some patients require high dose atropine to counteract the effects on heart rate (HR) and blood pressure (BP). This study describes the factors associated with high dose atropine therapy and the use of adrenaline to reverse the inadequate HR response to atropine.

METHODS

Consecutive patients admitted to the intensive care unit (ICU) were prospectively recruited. Demographic data, treatment and outcomes of patients who failed to achieve target HR (100/min) or systolic BP >90 mm Hg with either a cumulative atropine dose of 100-mg within 6-h following admission or an infusion of 30 mg/h for at least 3-h were compared with patients who achieved the targets. Factors associated with high dose atropine therapy were explored using logistic regression analysis and expressed as odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

Of the 181 patients admitted with OP or carbamate poisoning, 155 patients fulfilled inclusion criteria. The mean (SD) age was 35.7 (15.8) years; admission APACHE-II score was 14.6 (7.5). Heart rate and/or BP target was not achieved in 13.6%. In these patients, target HR was achieved after adding adrenaline infusion at 2-4 μg/min. Ventilation duration (11.6 ± 6.3 vs. 8.4 ± 6.9 days, p = 0.05) and ICU stay (12.3 ± 5.8 vs. 8.9 ± 5.8 days, p = 0.01) were longer in patients requiring high dose atropine when compared with others. On multivariate logistic regression analysis, shorter time to presentation to hospital (p = 0.04) was associated with need for high dose atropine. Overall mortality was 9% and similar in both groups (p = 0.41).

CONCLUSIONS

High dose atropine therapy is required in a subset of patients with OP and carbamate poisoning and was associated with longer ventilation duration and ICU stay. Adrenaline infusion improved hemodynamics in these patients.

DARK Classics in Chemical Neuroscience: Atropine, Scopolamine, and Other Anticholinergic Deliriant Hallucinogens

Anticholinergic drugs based on tropane alkaloids, including atropine, scopolamine, and hyoscyamine, have been used for various medicinal and toxic purposes for millennia. These drugs are competitive antagonists of acetylcholine muscarinic (M-) receptors that potently modulate the central nervous system (CNS). Currently used clinically to treat vomiting, nausea, and bradycardia, as well as alongside other anesthetics to avoid vagal inhibition, these drugs also evoke potent psychotropic effects, including characteristic delirium-like states with hallucinations, altered mood, and cognitive deficits. Given the growing clinical importance of anti-M deliriant hallucinogens, here we discuss their use and abuse, clinical importance, and the growing value in preclinical (experimental) animal models relevant to modeling CNS functions and dysfunctions.