Heroin-induced respiratory depression and the influence of dose variation: within-subject between-session changes following dose reduction.

Abstract

BACKGROUND AND AIMS:

Globally, more than 100 000 people die annually from opioid overdose. Opportunities to study physiological events in at-risk individuals are limited. This study examined variation of opioid dose and impact on respiratory depression in a chronic injecting heroin user at separate time-points during his long-term diamorphine maintenance treatment.

DESIGN:

A single-subject study over 5 years during which participant underwent experimental studies on diamorphine-induced respiratory depression, at changing maintenance doses.

SETTING:

A clinical research facility. Participant Male subject on long-term injectable diamorphine (pharmaceutical heroin) maintenance treatment for heroin addiction.

MEASUREMENTS:

Physiological measures of oxygen saturation (SpO2 ), end-tidal carbon dioxide (ETCO2 ) and respiratory rate (RR) were used to indicate severity of respiratory depression.

FINDINGS:

(1) After diamorphine injection, respiratory regulation became abnormal, with prolonged apnoea exceeding 20 sec (maximum 56 sec), elevated ETCO2 (maximum 6.9%) and hypoxaemia (minimum SpO2 80%). (2) Abnormalities were greater with highest diamorphine dose: average SpO2 was 89.3% after 100 mg diamorphine versus 93.6% and 92.8% for the two 30-mg doses. (3) However, long apnoeic pauses and high levels of ETCO2 % were also present after lower doses.

CONCLUSIONS:

With marked inter-session variability, these findings corroborate observations of inconsistent relationships between opioid dose and overdose risk.

• Authors: Basak Tas, Caroline J Jolley, Nicola J Kalk, Rob van der Waal, James Bell, John Strang
• Journal: Addiction (Abingdon, England) (Addiction) Vol. 115 Issue 10 Pg. 1954-1959 (10 2020) ISSN: 1360-0443 [Electronic] England
• PMID: 32057141 (Publication Type: Journal Article)
• Copyright: © 2020 Society for the Study of Addiction.

Chemical References

• Analgesics, Opioid
• Heroin

Topics

• Analgesics, Opioid (pharmacology)
• Dose-Response Relationship, Drug
• Drug Tapering
• Heroin (pharmacology)
• Heroin Dependence (drug therapy, physiopathology)
• Humans
• Male
• Middle Aged
• Respiratory Insufficiency (chemically induced)