Objective: To assess the effectiveness of the long acting local anesthetic
(0.25% ropivacaine) intermittently administered through an extrapleural
paravertebral catheter versus a thoracic epidural catheter on postthoracotomy
pain relief.
Patients and Methods: Forty patients undergoing elective posterolateral
thoracotomy during the period between July 2001 and August 2002
were prospectively studied. They were randomly allocated into two
groups (A and B) of 20 patients each. Group A patients received an epidural-type
catheter inserted by the surgeon into an extrapleural pocket extending
for 2 to 3 intercostal spaces both above and below the thoracotomy
incision alongside the vertebral column by the conclusion of operation.
A bolus dose of 15 ml of 0.25% ropivacaine analgesia was given during
chest closure.Group B patients received a thoracic epidural catheter inserted
by the anesthesiologist at T5-6 or T6-7 interspace before induction
of anesthesia. A bolus dose of 15 ml of 0.25% ropivacaine analgesia was
given after confirming the correct position of the epidural catheter. Postoperatively,
patients in both groups were intermittently administered 25 ml
of 0.25% ropivacaine analgesia at 6 hourly intervals for 3 successive
days. Pain scores (verbal rating scale), requirement of additional analgesia
(NSAID), pulmonary function test, shoulder range of motion as well as
any complication encountered were assessed and compared in both
groups.
Results: Excluding the immediate postoperative arousal period, the extrapleural
analgesia provided better pain control than the thoracic epidural
analgesia in the form of less mean values of the verbal rating scale
(VRS). Also, the extrapleural analgesia provided more rapid improvement
of pulmonary functions, progressive increase of the shoulder range of motion
(SROM) as well as less analgesic requirements in comparison to the
thoracic epidural analgesia. However these differences were statistically
non-significant (P>0.05). Side effects namely, hypotension, bradycardia
and atelectasis were troublesome only in the thoracic epidural analgesia
group. There was no mortality in either group.
Conclusion: Extrapleural paravertebral catheter technique is a valuable
alternative to the thoracic epidural technique for post-thoracotomy
pain relief. It is easy to perform by the surgeon at the conclusion of operation
without complications or side effects. It should be considered as the
first choice alternative for post-thoracotomy pain control. |
