High consumption of coffee powder turns lethal for woman: BMJ case report

Dr Rebecca Harsten from Queen Elizabeth Hospital in London has reported a case of lethal overdose of caffeine or caffeine poisoning.The findings are reported in BMJ Case reports.

Caffeine is a psychoactive stimulant consumed in products like coffee, tea, and soft/energy drinks. Usually it is ingested in moderated doses but caffeine is an extremely powerful substance that can be dangerous and even lethal if taken too much in its pure or concentrated powdered form.

This case study serves as an alarming refresher on caffeine overdose showing what can happen if people swallow massive amounts of powdered caffeine.

According to the history, a 26-year-old patient turned up in emergency about 3 hours after she ingested two heaped teaspoons of powdered caffeine (approximately 20 grams) experiencing palpitations, sweating, anxiety, and difficulty breathing. On examination, doctors found she had an abnormally rapid heart rate and low blood pressure, and was experiencing both hyperventilation and vomiting.

Her ECG revealed she had a form of abnormal heart rhythm called polymorphic ventricular tachycardia, and tests showed a build-up of acid in her body, called metabolic acidosis, along with respiratory alkalosis and a high count of white blood cells.

The first measurement of caffeine in her blood showed higher-than-lethal concentration with caffeine levels reaching 147.1 mg/L at 7 hours into her ordeal.

According to FDA's reckoning, that puts the dose in the ballpark of 50 to 60 cups of coffee at once, and as Harsten and her co-authors report, it's more than enough to kill a person.

The patient was moved to intensive care, sedated, given haemodialysis, and put on a ventilator after initial treatment with fluid and electrolyte replacement treatment was not effective.

She was also given an intravenous bicarbonate treatment to correct her acid-base status, a magnesium sulphate drug to control her arrhythmia, and activated charcoal to help clear out toxins from her kidneys. She was also given norepinephrine to combat caffeine's effect on blood pressure.

A fatty emulsion called intralipid was administered, and not for its usual purpose as a source of energy and nutrients. In recent years, the substance has increasingly been used to help remove potentially toxic fat-soluble materials from the body.

Two days following the overdose the patient was extubated, haemodialysis was stopped and norepinephrine was weaned off. The patient was discharged after a further 7 days. Serial caffeine levels were taken during this patient's care; the highest measured caffeine concentration 7 hours after ingestion was 147.1 mg/L. The known lethal dose of caffeine is 80 mg/L. Intralipid and haemodialysis represent a new and viable treatment in life-threatening caffeine overdose.

Intravenous magnesium may terminate unstable arrhythmias in caffeine-poisoned patients.She remained under observation in intensive care for another week.

A month after discharge, her doctors say she was doing well, receiving support from her family, and engaging with psychiatric care. She also visited ICU, to thank the team who saved her life.

Caffeine ingestions of greater than 1–2 g cause significant toxic effects," the researchers write in their paper. "Fatal caffeine overdoses have occurred following ingestions of >5 g or with blood caffeine concentrations >80 mg/L."

The researchers note that while there are no official guidelines on the management of caffeine overdose, which is ultimately a rare scenario, this case and others like it suggest that the combination of intralipid and haemodialysis could "represent a new and viable treatment in life-threatening caffeine overdose".

For further reference log on to:

http://dx.doi.org/10.1136/bcr-2020-234256