Postoperative pain in surgical inpatients: treatment still unsatisfactory

2007/12/18

Despite an acute pain protocol, postoperative pain treatment is unsatisfactory, summarized the Dutch research group from the Department of Anaesthesiology and Pain Treatment at the University Hospital of Maastricht (Netherlands). This is especially true after intermediate and major surgical procedures on an extremity or on the spine.

Objective of the recent study published online first in the European Journal of Anaesthesiology was to measure the prevalence of postoperative pain. The authors assessed 1490 surgical inpatients who were receiving postoperative pain treatment according to an acute pain protocol.

Pain measurements (using a visual analogue scale from 0 to 100) were obtained three times a day on the day before surgery and on postoperative days 0-4, and mean pain intensity scores were calculated. Inpatients were classified as having no pain (score 0-5), mild pain (score 6-40), moderate pain (score 41-74), or severe pain (score 75-100).

VAS scores showed that 1 hour after surgery 357 patients (26%) were suffering from moderate pain, and 210 (15%) were suffering from severe pain. Three hours after the operation, these percentages were 26% and 10%, respectively. So moderate and severe pain scores combined were stated in 41% of the patients on day 0, decreasing to 30% on day 1 and 19%, 16% and 14% on days 2, 3 and 4.

In the study, the most painful surgical procedures (moderate and severe pain, VAS 40 to more than 75) were upper and lower extremities, thorax, abdomen and back/spinal column surgery. Upper extremity operations and thorax surgery with incision of the pleura were classified in the major surgery category, so advanced pain treatment had to be considered. The prevalence of moderate or severe pain in the abdominal surgery group was high on postoperative days 0 or 1 (30 to 55%). A high prevalence of moderate or severe pain was found during the whole of days 1-4 in the extremity surgery group (20-71%) and in the back/spinal surgery group (30-64%).

Even if pain scores declined from day 2 until day 4, almost 15% of all patients still had moderate or severe pain on day 4. Dr. Micha Sommer and colleagues discussed the following possible reasons for this unsatisfactory pain control:

1. A small proportion of the high pain levels in the major surgery group might be explained by failure of the epidural catheters, which had an incidence of 5.
2. A proportion may have been due to suboptimal pain management in the hospital ward.
3. The acute pain protocol itself might have been insufficient if the estimate of anticipated postoperative pain was too low.
4. Besides various ‘demographic’ and general medical aspects, individual psychological factors may also have influenced postoperative pain, such as preoperative anxiety.

Sommer M, de Rijke JM, van Kleef M, et al. The prevalence of postoperative pain in a sample of 1490 surgical inpatients. Eur J Anaesthesiol 2007;24:1-8 [online ahead of print]