Related Experiment Videos
Respiratory depression by analgesics at 41 bar
K Furset1, L Aanderud, I Tyssebotn
1Department of Physiology, University of Bergen, Norway.
Undersea Biomedical Research
|May 1, 1989
Summary
Morphine and fentanyl equally affected rat respiration at surface and high pressures. Respiratory depression from these analgesics showed no significant pressure-dependent differences in this study.
Area of Science:
- Pharmacology
- Physiology
- Environmental Medicine
Background:
- Opioid analgesics like morphine and fentanyl are widely used.
- Understanding their effects on respiration under varying environmental pressures is crucial for safety.
Purpose of the Study:
- To investigate the impact of morphine and fentanyl on respiratory function and tissue CO2 levels.
- To compare these effects at surface pressure versus elevated ambient pressure (41 bar).
Main Methods:
- Conscious, trained rats were administered equianalgesic intravenous doses of morphine (7 mg/kg) and fentanyl (0.025 mg/kg).
- Respiration and transcutaneous tissue CO2 were monitored at 1 bar (surface) and 41 bar ambient pressure.
- Statistical analysis was performed to compare respiratory depression between pressure conditions for each analgesic.
Main Results:
- Fentanyl induced rapid, short-lived respiratory depression, consistent at both 1 and 41 bar.
- Morphine also caused respiratory depression with similar pressure-independent effects, but with a delayed onset and longer duration.
- No statistically significant differences in the degree of respiratory depression were observed at 41 bar compared to 1 bar for either morphine or fentanyl.
Conclusions:
- The respiratory depressant effects of equianalgesic doses of morphine and fentanyl in rats are not significantly altered by a high ambient pressure of 41 bar.
- These findings suggest that pressure-induced changes in respiratory function may not be a primary concern with these specific opioids at the tested doses and conditions.