Intercostal thoracotomy closure: transcostal sutures as a less painful alternative to circumcostal suture placement

To determine if transcostal thoracotomy closure resulted in less pain than circumcostal closure.

Experimental cadaver and prospective clinical study.

Two canine cadavers and 13 adult, 22-29 kg dogs.

Phase 1: In 2 cadavers, 4 suture passage techniques were evaluated to determine the incidence of nerve entrapment in circumcostal intercostal thoracotomy closure. Phase 2: Pain after circumcostal closure (7 dogs) or transcostal closure (6 dogs) of a 4th intercostal space thoracotomy was evaluated by use of pain threshold scores, fentanyl administration rates, heart and respiratory rates, and numerical ratings for behavior. Arterial blood gas analyses were obtained 4 hours postoperatively. Transcostal closure was accomplished by drilling 5-6 small holes in the 5th rib and passing sutures through the holes and around the 4th rib to achieve closure. Pain threshold scores (PTS) were measured by an observer unaware of closure assignment, at 2, 4, 12, and 24 hours after closure by applying slowly increasing pressure to the incision line using a load cell. Rates of fentanyl administration were adjusted based on subjective impressions of dog comfort by a second observer unaware of closure assignment.

A 70-100% incidence of nerve entrapment was found for all circumcostal techniques. PTS was higher (P=.045) and fentanyl infusion rates were lower (P=.001) for the transcostal group at 2, 4, 12, and 24 hour postoperatively compared with the circumcostal group.

There is a high incidence of nerve entrapment using circumcostal closure techniques. A transcostal technique appears to be associated with less pain during the first 24 hours postoperatively.

Based on lower pain scores, transcostal thoracotomy closure may be preferable to circumcostal closure techniques.