Are intracostal sutures better than pericostal sutures for closing a thoracotomy?

A best evidence topic was written according to a structured protocol. The question addressed was to identify which thoracotomy closure method lends itself to the least postoperative pain. Altogether 109 papers were found using the reported search; of which, seven repre-sented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that the closure by intracostal sutures with intercostal nerve sparing offers a superior postoperative pain pro ﬁ le for thoracotomy patients when compared with conventional techniques. Up to 1-year follow-up has shown that this technique (avoiding strangulation of the intercostal nerve) leads to lower postoperative pain and analgesic use, better ambulation and a quicker return to daily activities. Three papers (including two randomized trials) found intracostal sutures with intercostal nerve sparing techniques to be superior to conventional methods such as pericostal suture closure. Rib approximation with intercostal nerve sparing was found to be superior to rib approximation without nerve sparing in one study. Two studies associated with the creation of an intercostal muscle ﬂ ap prior to the insertion of a rib retractor to be associated with signi ﬁ cantly reduced postoperative pain. One study described a novel ‘ edge-closure ’ technique, comparable to the closure with intracostal sutures without drilling, to be superior to conventional closure with pericostal sutures. Postoperative pain is a signi ﬁ cant issue faced by thoracic surgeons both in-hospital and in the longer term where patients may complain of chronic thoracotomy pain. We would therefore recommend that some form of intercostal nerve protection be implemented during thoracotomy opening and closure.


INTRODUCTION
A best evidence topic was constructed according to a structured protocol. This protocol is fully described in the ICVTS [1].

CLINICAL SCENARIO
You have just embarked on a video-assisted thoracoscopic surgery lobectomy programme and are convinced that a reduction of rib spreading and intercostal nerve crushing reduces pain. Thus you come to a case involving thoracotomy for a difficult intrapericardial pneumonectomy. On closure you reflect that despite reducing rib spreading as much as possible, your retractor must have crushed the nerve under the fifth rib and the pericostal sutures must be crushing the intercostal nerve below the sixth rib. You wonder whether a nerve sparing approach has been proven to reduce post-thoracotomy pain.

SEARCH STRATEGY
The search Medline from 1948 to November 2011 using the OvidSP interface: (Thoracotomy.mp OR exp Thoracotomy/) AND ( pericostal.mp OR intracostal.mp OR muscle flap.mp).

SEARCH OUTCOME
A total of 109 papers were found using the above search. From these, seven papers were identified that provided the best evidence to answer the question. These are presented in Table 1.

RESULTS
Allama et al. [2] prospectively randomized 120 patients undergoing thoracotomy into two groups: one undergoing closure with an intercostal muscle flap and intracostal sutures and one undergoing closure with pericostal sutures. The postoperative pain score throughout the first week was significantly lower in the intercostal muscle flap/intracostal suture group, which also had significantly earlier ambulation, return to daily activities and Prospective randomized controlled trial (level 2 evidence) 120 patients undergoing posterolateral thoracotomy for a variety of thoracic diseases were prospectively randomized into two equal groups undergoing thoracotomy closure with either intercostal muscle flap (IMF) and intracostal sutures (ICSs)        Week 12: n/a  lower doses of analgesics. Additionally, the intercostal muscle flap/intracostal suture group had significantly lower pain scores and use of postoperative analgesia at 1 week and at 1 month. At 3 months, the intercostal muscle flap/intracostal suture group had significantly lower analgesic use but there was no difference in the pain score. There were no significant differences between groups when comparing analgesic use and pain scores at 6 months. Bayram et al. [3] prospectively randomized 60 patients undergoing thoracotomy into two groups: one undergoing closure with intercostal sutures compressing the intercostal nerve bundle and one with intercostal nerve dissection and preservation before intracostal sutures were applied. Closure with intracostal sutures without intercostal nerve compression was associated with significantly lower visual analogue scores at rest and while coughing. Observer verbal ranking scores within a 48-h postoperative period were also significantly lower in this group. There was no significant difference between the groups in terms of their Ramsey sedation score over 48 h, consumption of postoperative patient controlled epidural analgesia or von Frey hair test results (a method used to assess hyperalgesia) at 30-day follow-up.

Continued
Wu et al. [4] prospectively randomized 72 patients undergoing non-muscle sparing thoracotomy into two groups: one undergoing closure with muscle flap and intracostal sutures and the other undergoing closure with intracostal sutures. The authors found no statistical differences between pain scores at rest or during coughing postoperatively. However, the intake of oxycodone was significantly lower in the muscle flap group during postoperative days 4-7.
Cerfolio et al. [5] prospectively investigated 160 patients undergoing thoracotomy. The sample was randomized into two groups, one group with an intercostal muscle harvest that was left to dangle beneath the rib retractor and the other group where this intercostal muscle flap was divided anteriorly and reflected posteriorly prior to retraction. On postoperative days 1 and 2, the intact muscle flap group had significantly lower visual pain scores and at postoperative weeks 3, 4, 8 and 12, the intact muscle flap group had significantly lower mean numeric pain scores and had used fewer analgesics. At 12 weeks, patients in the intact muscle flap group were more likely to have returned to baseline activity.
Cerfolio et al. [6] prospectively randomized 114 patients undergoing a pulmonary resection to either a thoracotomy or a thoracotomy but with harvesting of an intercostal muscle from the lower rib (to protect the intercostal nerve) before chest retraction. After harvesting of the flap, it was transacted anteriorly and reflected posteriorly prior to the insertion of the retractor. In this group, the numeric pain scores were lower on postoperative days 1 and 2 and at weeks 1, 2, 3, 4, 8 and 12. In addition, this group had a smaller decrease in spirometric values, was less likely to be using analgesics, was more likely to have returned to normal activity and had a lower incidence of atrial arrhythmia.
Sakaura et al. [7] retrospectively reviewed 184 patients who underwent posterolateral (n = 141) or anteroaxillary thoracotomy (n = 43). In addition, these patients either had (i) an intercostal muscle flap harvested before using retraction to prevent compression of the cranial intercostal (n = 72), (ii) the thin space between the inferior edge of caudal rib and the neurovascular bundle was sutured during closure to prevent strangulation of the intercostal nerve and vessels on the caudal side (edge closure technique) (n = 97) or (iii) conventional closure with pericostal sutures (n = 87) which comprise the neurovascular bundle. Up to 2 months postoperatively, anteroaxillary thoracotomy patients had less pain compared with the posterolateral thoracotomy patient group. It was also found that intercostal bundle sparing edge-closure techniques reduce postoperative pain significantly (up to 12 months) when compared with the conventional closure. The use of an intercostal muscle flap prior to rib retraction showed less postoperative pain up to 1 month after the operation.
Cerfolio et al. [8] retrospectively reviewed 280 consecutive patients following thoracotomy: half had closure with pericostal sutures and a similar-sized consecutive group received an intracostal suture closure. Intracostal sutures resulted in significantly less postoperative pain during the full course of the study (3 months). Intracostal suture patients were also less likely to report any pain as being hot, burning or stabbing (a symptom of intercostal nerve compression).

CLINICAL BOTTOM LINE
Postoperative pain is a significant issue faced by thoracic surgeons. During in-hospital stay, there is of course concern that increased pain may lead to poorer outcomes due to complications such as sputum retention and in the longer term there is the risk of chronic thoracotomy pain. The seven studies examined in this article suggest that techniques offering some form of protection to the intercostal nerve (such as intracostal sutures or the use of an intercostal muscle flap) are associated with significantly reduced postoperative pain and analgesic consumption, even up to 12 months after surgery. Only two studies reported complication rates in detail, one of which showed a significantly reduced rate of atrial arrhythmia when an intercostal muscle flap was created prior to rib retraction.