Relationship between abnormal pupillary reactivity and the outcome of a psychotropic drug overdose

Outcome in intoxicated patients transported by a physician-staffed helicopter in Japan from 2015 to 2020

Aim

We retrospectively investigated the current status of poisoned patients who had been transported by a physician-staffed helicopter emergency medical service and their final outcomes using data from the JAPAN DOCTOR HELICOPTER REGISTRY SYSTEM.

Methods

The following details of dispatch activity were collected from the database of the JAPAN DOCTOR HELICOPTER REGISTRY SYSTEM: patient age and sex, timing of dispatch request, presence of cardiac arrest, vital signs, medical intervention, main etiology of intoxication, and final outcome. The patients were divided into two groups: those with a good outcome and those with a poor outcome. The variables were compared between the two groups.

Results

A total of 336 patients were intoxicated. Psychotropic drug overdose was the dominant cause, followed by carbon monoxide and ethanol. The median Glasgow Coma Scale score was significantly higher in the good outcome group than in the poor outcome group. The rates of cardiac arrest, interventions to secure an airway and/or assist with ventilation, and drug administration were significantly lower in the good outcome group than in the poor outcome group. There were no records concerning the decontamination of the intoxicating substance at the scene or during air evacuation.

Conclusion

The study suggests that various factors may influence the outcomes of patients with different types of intoxication. These findings offer valuable insights that could help to establish effective treatment strategies and the operation of doctor helicopters for intoxicated patients.

Early Absent Pupillary Light Reflexes After Cardiac Arrest in Patients Treated with Therapeutic Hypothermia

Loss of pupillary light reactivity is one recognized indicator of poor prognosis after cardiopulmonary resuscitation (CPR). However, drug overdose, low cardiac output, and/or resuscitation drugs can lead to impaired pupillary light reflex. To investigate pupillary light reflex status before therapeutic hypothermia (TH) in relation to neurological outcome, we retrospectively reviewed the data of a prospectively implemented TH protocol in patients with cardiac arrest (CA) at Mayo Clinic in Jacksonville, Florida (January 2006-January 2012), and Mayo Clinic in Scottsdale, Arizona (August 2010-March 2014). During this period, all CA patients who underwent hypothermia were included. These patients were selected from an institutional database and hypothermia data set. The Cerebral Performance Category (CPC) at time of discharge was our primary outcome measure. A CPC of 1 to 2 was defined as good outcome and a CPC from 3 to 5 was defined as poor outcome. We identified 99 patients who had CA treated with TH. Twenty-nine patients (29%) had pupils that were nonreactive to light on admission examination before TH, eight of whom later had return of pupil reactivity by day 3. Two of these 29 patients (6.9%) had good outcome, compared to 24 of 70 patients (34.3%) with pupils that were reactive to light (p = 0.005). Both of these patients had CA after illicit drug overdose. Early nonreactive pupils occurred in almost a third of patients after CPR and before TH in our patient population. Recovery of pupillary light reactivity is possible, and in a small minority of those cases (particularly when CA is preceded by the use of illicit drugs), a good outcome can be achieved.