Comparison of effects and plasma concentrations of opioids between elderly and middle-aged patients after cardiac...

In elderly patients, opioids may cause prominent postoperative sedation and respiratory depression. We evaluated the influence of age on the effects of opioids and plasma concentrations of fentanyl and oxycodone in cardiac surgery patients.

Thirty (>or=75 years, gender M9/F21) and 20 (

The elderly had a higher plasma concentration of fentanyl at the end of surgery than younger patients (5.7+/-2.2 vs. 3.8+/-1.2 ng/ml, P=0.001). The plasma concentrations of oxycodone were comparable between the groups. The interval between the second and the third oxycodone dose was longer in the elderly patients (P=0.036). Pain intensity on the verbal rating scale was lower at the 45-min assessment point after all three oxycodone test doses (P=0.008) and sedation scores were significantly higher after the third dose in the elderly patients (P=0.035).

In elderly patients, the plasma concentration of fentanyl was higher but plasma levels of oxycodone were at a similar level compared with middle-aged patients. However, the elderly patients had less pain and were more sedated after doses of oxycodone.