Plasma lactate concentration as an indicator of plasma caffeine concentration in acute caffeine poisoning

Massive suicidal ingestion of caffeine: a case report with investigation of the cardiovascular effect/concentration relationships

BACKGROUND

Caffeine poisoning may cause life-threatening arrhythmias and hemodynamic failure. We aimed to investigate the toxicokinetics (TK), toxicodynamics (TD) and TK/TD relationships of caffeine in a case of poisoning.

CASE REPORT

A 47-year-old male ingested pure anhydrous caffeine powder (70 g) in a suicide attempt. He developed agitation, tachycardia, and two episodes of ventricular fibrillation treated with defibrillation and tracheal intubation. He was successfully managed using intravenous infusions of esmolol and norepinephrine.

METHODS

We modelled the time-course of plasma caffeine concentration (TK study using online liquid chromatography-tandem mass spectrometry), the time-course of blood lactate concentration and infusion rates of esmolol and norepinephrine (TD studies) and the TK/TD relationships.

RESULTS

Caffeine TK was of first-order peaking at 258 mg/L with an elimination half-life of 46.2 h and clearance of 2.2 L/h. Caffeine-related effects on blood lactate (peak, 10 mmol/L at 1.25 h postingestion) were described by a Bateman-type equation (formation rate, 0.05 mmol/mg.h; elimination rate, 0.9 mmol/mg.h). Esmolol and norepinephrine infusion rates to reverse caffeine-related cardiovascular effects (peaks at 51-h postingestion) fitted well with a sigmoidal E_max model (EC₅₀, 180.0 and 225.9 mg/L, respectively; Hill coefficient, 10.0).

CONCLUSION

Massive caffeine ingestion is characterized by prolonged caffeine elimination. TK/TD relationships are helpful to quantify caffeine-related catecholaminergic effects.

Flying From Hospital to Hospital: A Case of Caffeine Intoxication

A 54-year-old woman with a history of excess weight and active smoking presented to the emergency department (ED) due to syncope after a long flight. She reported a similar episode in the previous month, which had also occurred after a long air voyage. She presented with hypotension, dehydration, and hyperlactacidemia. The clinical team ruled out acute coronary syndrome, pulmonary embolism, and cerebrovascular accident. After clinician insistence, she reported having ingested anhydrous caffeine, an over-the-counter diuretic usually used by individuals seeking to lose weight, and a diagnosis of caffeine intoxication was made. The over-the-counter sale of this apparently innocuous substances is a rising phenomenon, and physicians should be aware of the signs of its ingestion.

Urinary glucose and ketone bodies as indicators of acute caffeine poisoning

AIM

In various countries, many fatal health problems have been reported due to high intake of caffeine-rich energy drinks, tablets, and powders. In patients with acute caffeine poisoning, determination of blood caffeine concentration is an important yet difficult task. We aimed to assess whether the presence of glucose and ketone bodies in urine reflected the blood caffeine concentration in patients with acute caffeine poisoning.

METHODS

From April 2010 to March 2018, 25 patients with an overdose of only caffeine-rich tablets were admitted to our hospital. Their clinical features were investigated. In addition, we investigated whether the glucose and ketone bodies in the urine reflected blood caffeine concentration in 23 patients who underwent the urine qualitative test at admission.

RESULTS

The majority of the patients were young healthy women, whose average caffeine ingestion was 15.6 ± 8.1 g. Initial urine examinations showed glucose in 60% (14/23) of patients and ketone bodies in 57% (13/23) of patients. Ketone bodies or glucose were found in 78% (18/23) of the patients. The correlation between blood caffeine concentration and urinary glucose was R = 0.625, blood caffeine concentration and ketone bodies was R = 0.596, and blood caffeine and both was R = 0.76.

CONCLUSION

Urine qualitative test is effective for differential diagnosis and severity assessment of acute caffeine poisoning in patients.

Dangerous mistake: an accidental caffeine overdose

Caffeine (1,3,7-trimethylxanthine) is a natural product commonly presented in food’s composition, beverages and medicinal products. Generally, it is thought to be safe under normal dosage, yet it can be fatal in case of severe intoxication. We report a case of a healthy 32-year-old woman who went to the local emergency department (ED) 30 min after ingesting, accidentally, 5000 mg of anhydrous caffeine for a preworkout supplement. At the ED, she presented an episode of presyncope followed by agitation. ECG showed polymorphic broad complex QRS tachycardia and arterial blood gas revealed metabolic acidaemia with severe hypokalemia. The dysrhythmia was successfully treated with intravenous propranolol. Acid–base and hydroelectrolytic disorders were also corrected. A persistent sinus tachycardia was observed in the first 2 days in the ward and 5 days later she was discharged asymptomatic with internal medicine follow-up.