Use of Extracorporeal Therapies to Treat Severe Caffeine Poisoning.

Introduction: Reflecting on recent reports suggesting the efficacy of extracorporeal blood purification, including hemodialysis, for severe caffeine poisoning, we conducted a retrospective 6-year follow-up study on acute caffeine poisoning in Japan particularly focusing on extracorporeal blood purification.

Methods: Patients transported to emergency facilities between April 2016 and March 2022 after consuming large or excessive amounts of over-the-counter drugs and energy drinks containing caffeine as a primary ingredient were included. We collected information on demographic characteristics, medical history, the caffeine-containing products consumed, clinical and laboratory findings, treatments, and outcomes using a questionnaire. We compared the data of patients who were treated with and without extracorporeal blood purification (blood purification vs. nonblood purification group). We also compared our findings with those of a previous related study.

Findings: Seventy-six patients were included. Patients in the blood purification group (n = 22) were significantly older (p = 0.02), ingested higher estimated doses of caffeine (p < 0.01), demonstrated higher pulse rates (p = 0.01), respiratory rates (p = 0.03), and serum glucose levels (p = 0.05) on admission, resulting in longer hospital stays (p < 0.01) than those in the nonblood purification group (n = 54). However, their backgrounds, clinical features on arrival, and clinical signs and symptoms during the clinical course were similar between this and the previous study. Compared to the previous study, this study had a higher percentage of patients who underwent extracorporeal blood purification (16.8% vs. 28.9%; p = 0.07), including hemodialysis (10.9% vs. 22.4%; p = 0.06); nevertheless, no statistically significant differences were observed in the prognoses between the studies.

Conclusions: Currently, the use of extracorporeal blood purification including hemodialysis for the treatment of caffeine poisoning is being promoted in Japan; however, the decision to administer it mostly depends on the patients' ingested doses or vital signs, and not on the serum caffeine levels. Further studies are warranted to confirm whether extracorporeal blood purification improves the prognoses of patients with severe caffeine poisoning.