Intercostal Muscle Flap for Decreasing Pain After Thoracotomy: A Prospective Randomized Trial

Transcription

1 ORIGINAL ARTICLES: SURGERY: The Annals of Thoracic Surgery CME Program is located online at To take the CME activity related to this article, you must have either an STS member or an individual non-member subscription to the journal. Intercostal Muscle Flap for Decreasing Pain After Thoracotomy: A Prospective Randomized Trial Amr Mohammad Allama, MD Cardiothoracic Surgery Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt Background. Intercostal nerve damage is often suggested to be the cause of pain after thoracotomy. Methods. This was a prospective randomized study of 120 patients who had posterolateral thoracotomy. They were equally divided into two groups, the first in which intercostal muscle flap and intracostal sutures were used, and the other group in which the usual pericostal sutures were used. These two groups were compared regarding operative time, rib fracture, postoperative pulmonary functions, time to ambulation, pain score in the first week, doses of analgesics injected in the epidural catheter, postoperative complications, chest tube drainage, hospital stay, return to daily activities, and pain score and use of analgesics at 1, 3, and 6 months. Results. Postoperative pain score throughout the first week was significantly lower in the patients in the intercostal muscle flap group, who had also a significantly earlier postoperative ambulation and return to normal daily activities, and received significantly lower doses of postoperative analgesics. After 1 month, patients in the intercostal muscle flap group had a significantly lower pain score and use of analgesics. After 3 months, pain score was not significantly different between both groups, but the use of analgesics was significantly lower in the intercostal muscle flap group. After 6 months, no significant difference was present between both groups with regard to pain score or the use of analgesics. Conclusions. Intercostals muscle flap and intracostal sutures are rapid, safe, and effective procedures in decreasing early pain after thoracotomy with subsequent earlier return to normal daily activities and lesser use of analgesics. (Ann Thorac Surg 2010;89:195 9) 2010 by The Society of Thoracic Surgeons Despite increased knowledge about the pathophysiology and pharmacology of pain, acute postoperative pain still remains a major problem. Patients continue to report that their primary concern before surgery is the severity of postoperative pain [1]. Studies have shown that high levels of immediate postoperative pain are associated with an increase in the likelihood of chronic pain [2]. Chronic pain was reported in 40% to 80% of patients after thoracotomy [3 7] and in 20% to 40% after video-assisted thoracic surgery [8, 9]. The nociceptive pathways that are responsible for postthoracotomy pain are still poorly understood. It is a complex physiologic cascade involving multiple neurotransmitters and excitatory and inhibitory pathways that are difficult to target and quantify. Possible sources of nociceptive input that may contribute to pain after thoracic surgery are multiple and include the site of the surgical incision, disruption of the intercostal nerves, inflammation of the chest wall structures adjacent to the Accepted for publication July 30, Address correspondence to Dr Allama, Cardiothoracic Surgery Department, Faculty of Medicine, Menoufia University, Sheben-Elkom, Yassen Abd-Elghaffar Street, Menoufia, Egypt; amrallama2005@ yahoo.com. incision, pulmonary parenchyma, pleura, and thoracostomy drainage tubes [10]. Intercostal nerve dysfunction resulting from surgical incision, retraction, trocar placement, or suture is common and plays a role in both acute and chronic pain that follow thoracic surgery [11]. Cerfolio and associates studied the effects of intracostal sutures [12], divided intercostal muscle flap [13], and nondivided intercostal muscle flap [14], and found that these techniques lead to reduced postthoracotomy pain. In this prospective randomized trial, the effect of nondivided intercostal muscle flap and intracostal sutures (protecting the intercostal nerves from trauma) on early postoperative pain were investigated, comparing this technique with traditional pericostal sutures. Patients and Methods A prospective randomized study of 120 patients was performed from October 2005 to October 2008 in the Cardiothoracic Surgery Department in Menoufia University Hospital, Egypt. All patients had different thoracic diseases indicating posterolateral thoracotomy. Children (younger than 19 years) and patients with a history of previous thoracotomy or severe chest trauma with rib 2010 by The Society of Thoracic Surgeons /10/$36.00 Published by Elsevier Inc doi: /j.athoracsur

2 196 ALLAMA Ann Thorac Surg INTERCOSTAL MUSCLE FLAP 2010;89:195 9 Fig 1. Flow diagram of patients allocated in the study. fractures were excluded from the study. Before starting the study, the ethics committee of the Menoufia Faculty of Medicine approved it, and consent was taken from all patients informing them that they would have one of the two methods of chest entry. Patients were divided randomly into two groups; the first group included 60 patients in whom intercostal muscle flap and intracostal sutures were used (IMF group), and the other group included also 60 patients in whom the usual pericostal sutures were used (PCS group). Patients were allocated in both groups sequentially according to the computerized random number generator. Only the surgeon and his team were aware of the assignment of patients. Patients, data collectors, and the statistician were blinded to group assignment. Pulmonary function tests were performed for all patients preoperatively and at hospital discharge. All patients had a thoracic epidural catheter, which was removed on postoperative day 3. All patients had the standard posterolateral thoracotomy with division of the latissimus dorsi muscle and preservation of the serratus anterior muscle (when possible) by the same surgical team. The thoracic cavity was entered through the fifth or the sixth intercostal space except in 5 patients who underwent diaphragmatic plication, in which the thoracic cavity was entered through the eighth space. The intercostal space was opened by electrocautery over the upper border of the lower rib. In the IMF group, the intercostal muscle was harvested from the lower border of the corresponding rib by low electrocautery without dividing it, and care was taken not to damage the neurovascular bundle. A 10- to 15-cm segment was usually sufficient to put the chest retractor behind the intercostal muscle to avoid crushing it between the lower border of the rib and the upper blade of the retractor. A piece of gauze was placed between the blade and the rib to protect it from fracture. After completion of the procedure and placement of the chest tubes, the space was closed by four to six intracostal sutures (no. 2 polyglycolic acid). These sutures were passed in holes made by drilling the lower rib and passed over the upper border of the rib corresponding to the space. In the segment of the harvested muscle, the sutures passed behind the muscle to bring it between the two ribs. In the PCS group closure was done by four to six sutures (no. 2 polyglycolic acid) passed from the upper border of the rib of the lower intercostal space (seventh rib if the fifth space was opened) to the upper border of the rib corresponding to the space. Intercostal nerve block was performed in all cases using 10 ml of 0.5% bupivacaine injected around the neurovascular bundle of the opened space and two spaces above and below that space (2 ml in each space). The incidence of rib fractures (if any occurred) was recorded. The total operative time and the time needed to harvest the intercostal muscle was calculated. Chest tube drainage, complications (if any occurred), the time needed until ambulation, postoperative hospital stay, and the time needed to return to normal daily activities were recorded. Postoperative analgesic protocol was similar in all patients. It consisted of intramuscular 30 mg of ketorolac every 12 hours and on demand doses in the epidural catheter (10 ml of 0.25% bupivacaine). Operative and postoperative mortality were excluded from the study. Also patients in whom the intercostal muscle was used to cover the bronchial stump or who had a nonfunctioning epidural catheter or needed postoperative mechanical ventilation were excluded from the study. Patients lost to follow-up were also excluded from the study. The primary outcome of this study was pain, which was measured by a blinded trained physician using the numeric rating scale from 0 to 10 (0 no pain, 10 extreme pain) [15], which was explained to all patients preoperatively and was recorded postoperatively daily until the seventh day. Pain score was recorded in the morning before undertaking any effort or giving any analgesics. Patients discharged before the seventh day were contacted by telephone to record the scale. Pain score and the use of analgesics at 1, 3, and 6 months postoperatively were also recorded by a blinded trained physician who contacted the patients by telephone.

3 Ann Thorac Surg ALLAMA 2010;89:195 9 INTERCOSTAL MUSCLE FLAP 197 Table 1. Preoperative and Intraoperative Data a Table 2. Postoperative Data p Value Age (y) Sex Male 42 (70%) 39 (65%) Female 18 (30%) 21 (35%) Preoperative FEV 1 (% predicted) Type of operation Decortication 7 (11.7%) 10 (16.7%) Lobectomy 33 (55%) 29 (48.3%) Pneumonectomy 5 (8.3%) 7 (11.7%) Pleurectomy 3 (5%) 4 (6.7%) Resection of bullae 4 (6.7%) 5 (8.3%) Diaphragmatic plication 3 (5%) 2 (3.3%) Open biopsy 3 (5%) 2 (3.3%) Thoracic duct ligation 2 (3.3%) 1 (1.7%) Side of operation Right 28 (46.7%) 35 (58.3%) Left 32 (53.3%) 25 (41.7%) Total operative time (min) Rib fracture 7 (11.7%) 6 (10%) a p 0.05 for all variables. IMF intercos- FEV 1 forced expiratory volume in the first second; tal muscle flap; PCS pericostal sutures. Based on previous studies, sample size was calculated to be 51 patients in each group to provide 95% power and 0.05 statistical significance level. Data were collected and entered into the computer using SPSS program for statistical analysis, version 13 (SPSS, Inc, Chicago, IL). To measure the strength of association between discrete variables, 2 tests were done, and a probability value less than 0.05 was considered statistically significant. Continuous variables were tested for association by Student s t test. The Mann-Whitney test was performed for data that were not normally distributed. Postoperative FEV (% predicted) Time to ambulation a (hours) Pain score (0 10) Day a Day a Day a Day a Day a Day a Day a Number of analgesic doses a injected in the epidural catheter Complications Air leak 6 (10%) 5 (8.3%) Empyema 1 (1.7%) 1 (1.7%) Bleeding 1 (1.7%) 2 (3.3%) Wound infection 3 (5%) 2 (3.3%) Chest tube drainage (ml) Hospital stay (days) Return to normal daily activities (days) a a Statistically significant difference (p 0.05). IMF intercos- FEV 1 forced expiratory volume in the first second; tal muscle flap; PCS pericostal sutures. Postoperative pain score throughout the first week was significantly lower in the IMF group (Fig 2). Patients in the IMF group had a significantly earlier postoperative ambulation and return to normal daily activities. They Results Patients randomly allocated to this study were 141 patients. We excluded 11 patients from the IMF group and 10 patients from the PCS group, and the remaining 120 patients were statistically analyzed, 60 patients in each group (Fig 1). There were no significant differences between the two groups with regard to age, sex, type of operation, side of the disease, and preoperative forced expiratory volume in the first second (Table 1). The mean time needed for flapping the intercostals muscle was 4.6 minutes, which did not affect the overall operative time between the two groups. Seven patients in the IMF group and 6 patients in the PCS group had rib fractures with rib spreading. Postoperative forced expiratory volume in the first second at 1 week, postoperative complications, chest tube drainage, and hospital stay were not significantly different between the groups (Table 2). Fig 2. Pain score in both groups throughout the first postoperative week. (IMF intercostal muscle flap; PCS pericostal sutures.)

4 198 ALLAMA Ann Thorac Surg INTERCOSTAL MUSCLE FLAP 2010;89:195 9 Table 3. Follow-Up Data also received a significantly lower number of analgesic doses in the epidural catheter (Table 2). At 1 month postoperatively, patients in the IMF group had a significantly lower pain score, and a smaller number of patients in this group were still using analgesics (narcotic and nonnarcotic analgesics). At 3 months postoperatively, there was no significant difference between the two groups regarding pain score, but the use of analgesics was significantly lower in the IMF group. At 6 months postoperatively, no significant difference was present between the two groups regarding pain score or the use of analgesics (Table 3). Comment p Value 1 month Pain score (0 10) a Patients using analgesics 35 (58.3%) 46 (76.7%) a 3 months Pain score (0 10) Patients using analgesics 16 (26.7%) 27 (45%) a 6 months Pain score (0 10) Patients using analgesics 4 (6.7%) 5 (8.3%) a Statistically significant difference (p 0.05). IMF intercostal muscle flap; PCS pericostal sutures. This study aimed to evaluate the effect of intercostal muscle flap and intracostal sutures in decreasing pain after thoracotomy. It was designed after reading carefully the work of Cerfolio and colleagues [12, 13]. Pain after thoracic surgery has been reported to be among the most intense clinical experiences known. Moderate-to-severe postoperative pain may persist throughout the course of hospitalization and during the first postoperative month. Unrelieved acute pain after thoracic surgery not only contributes to postoperative pulmonary dysfunction but also may contribute to the development of postthoracotomy pain syndrome [16]. It has been suggested that both neuropathic [17] and myofascial [18] nociceptive pathways contribute to the development of postthoracotomy pain syndrome. Damage to intercostal nerves leads to neural degeneration, axonal sprouting, and the formation of localized neuromata. These axonal sprouts and neuromata can generate persistent spontaneous nerve activity, resulting in both allodynia and hyperalgesia [19]. Using an animal model for chronic postthoracotomy pain, Buvanendran and coworkers [20] showed that a 60-minute rib retraction between the fourth and fifth ribs produced a 50% incidence of long-term allodynia in rats. In contrast, a 5- or 30-minute rib retraction produced only a 10% to 11% incidence of allodynia, suggesting that more-prolonged pressure or stretch of the intercostal nerves is a key factor in the pathogenesis of chronic pain after thoracic surgery. Allodynic animals showed extensive axonal loss in the intercostal nerves of the retracted ribs, suggesting that the primary mechanism of postthoracotomy pain syndrome is neuropathic in origin [20]. It is possible that the rib retractor causes two injuries: direct ischemic injury caused by pressure from the retractor and a stretch injury [21]. Maguirea and colleagues [22] found that the neuropathic symptoms representing nerve dysfunction and damage are associated with more severe chronic pain and greater impact on patients lives, and tend to persist. However, when they studied intercostal nerve damage at the time of operation, they found that it was not associated with chronic pain or altered cutaneous sensation at 3 months postoperatively, suggesting that either the amount of intraoperative nerve damage is not indicative of long-term nerve damage or that there is a more significant cause for chronic pain other than intercostal nerve injury [23]. However, the effect of nerve damage on early postoperative pain was not studied. Steegers and colleagues [24] studied the nature of chronic pain after thoracotomy and found that the neuropathic component was present in 23% to 53% of patients and definitely not present in 47% of them. They also found that patients with neuropathic pain had more severe pain than patients with nonneuropathic pain. Regarding postoperative pain score, the results of the present study are concordant with those of Cerfolio and associates [12, 13], who reported a significantly lower pain score in the IMF group in the first 2 days [13] and at 1 month postoperatively [12, 13]. At 3 months postoperatively, they reported a significantly lower pain score in the IMF group [12, 13], but this was not seen in the present study. Cerfolio and coworkers [13] found no difference between the two groups for the amount of pain medicine used while in the hospital, but a significantly lower dose of analgesics was injected in the epidural catheter in the IMF group in the present study. In contrast to these results, Cerfolio and associates [13] found a significantly higher incidence of broken ribs intraoperatively and a significantly smaller decrease in spirometric values postoperatively in the IMF group. Cerfolio and colleagues [13] observed a high incidence of rib fractures intraoperatively in the IMF group (34%), but in their subsequent study this incidence decreased to 13% in the divided IMF group and 7% in the nondivided IMF group [14] (incidence in present study is 11.7%). Cerfolio and colworkers [12] reported 3 patients (2.14%) in their first series who had splitting of the lower rib during approximation of the intracostal sutures. These patients were elderly women. This problem did not occur in the present study, probably because there were a younger mean age (46.5 years versus 64 years) and a smaller percent of women (30% versus 40%). The mean time to perform an IMF was 4.6 minutes (5.2 minutes in the first 30 patients and 4 minutes in the last 30 patients), which is close to the time of Cerfolio and associates [13] (3.7 minutes), but in their last study this time was reduced to 45 seconds [14].

5 Ann Thorac Surg ALLAMA 2010;89:195 9 INTERCOSTAL MUSCLE FLAP 199 As the patients had different indications of surgery, the results of this study could be applied to any patient undergoing thoracotomy. The main limitation of this study is the subjective nature of pain, which is difficult to measure. In conclusion, intercostal muscle flaps and intracostal sutures are rapid, safe, and effective procedures in decreasing early pain after thoracotomy with subsequent earlier return to normal daily activities and lesser use of analgesics. References 1. Apfelbaum JL, Chen C, Mehta SS, et al. Postoperative pain experience from a national survey suggests postoperative pain continues to be undermanaged. Anesth Analg 2003;97: Katz J, Jackson M, Kavanagh B, Sandler AN. Acute pain after thoracic surgery predicts long-term post-thoracotomy pain. Clin J Pain 1996;1: Dajczman E, Gordon A, Kreisman H, Wolkove N. Long-term postthoracotomy pain. Chest 1991;99: Gotoda Y, Kambara N, Sakai T, Kishi Y, Kodama K, Koyama T. The morbidity, time course and predictive factors for persistent post-thoracotomy pain. Eur J Pain 2001;5: Kalso E, Perttunen K, Kaasinen S. Pain after thoracic surgery. Acta Anaesthesiol Scand 1992;36: Perttunen K, Tasmuth T, Kalso E. Chronic pain after thoracic surgery: a follow-up study. Acta Anaesthesiol Scand 1999;43: Pluijms WA, Steegers MA, Verhagen AF, Scheffer GJ, Wilder- Smith OH. Chronic post-thoracotomy pain: a retrospective study. Acta Anaesthesiol Scand 2006;50: Hutter J, Miller K, Moritz E. Chronic sequels after thoracoscopic procedures for benign diseases. Eur J Cardiothorac Surg 2000;17: Passlick B, Born C, Mandelkow H, Sienel W, Thetter O. Long-term complaints after minimal invasive thoracic surgery operations and thoracotomy. Chirurg 2001;72: Kavanagh BP, Katz J, Sandler AN. Pain control after thoracic surgery: a review of current techniques. Anesthesiology 1994;81: Benedetti F, Vighetti S, Ricco C, et al. Neurophysiologic assessment of nerve impairment in posterolateral and musclesparing thoracotomy. J Cardiovasc Thorac Surg 1998;115: Cerfolio RJ, Price TN, Bryant AS, Bass CS, Bartolucci AA. Intracostal sutures decrease the pain of thoracotomy. Ann Thorac Surg 2003;76: Cerfolio RJ, Bryant AS, Patel B, Bartolucci AA. Intercostal muscle flap reduces the pain of thoracotomy: a prospective randomized trial. J Thorac Cardiovasc Surg 2005;130: Cerfolio RJ, Bryant AS, Maniscalco LM. A nondivided intercostal muscle flap further reduces pain of thoracotomy: a prospective randomized trial. Ann Thorac Surg 2008;85: Katz J, Melzack R. Measurement of pain. Anesthesiol Clin North Am 1992;10: Reuben SS, Yalavarthy L. Preventing the development of chronic pain after thoracic surgery. J Cardiothorac Vasc Anesthes 2008;22: Conacher ID. Percutaneous cryotherapy for postthoracotomy neuralgia. Pain 1986;25: Hamada H, Moriwaki K, Shiroyama K, et al. Myofascial pain in patients with postthoracotomy pain syndrome. Reg Anesth Pain Med 2000;25: Coderre TJ, Katz J, Vaccarino AL, et al. Contribution of central neuroplasticity to pathological pain: review of clinical and experimental evidence. Pain 1993;52: Buvanendran A, Kroin JS, Kerns JM, et al. Characterization of a new animal model for evaluation of persistent postthoracotomy pain. Anesth Analg 2004;99: Rogers ML, Henderson L, Duffy JP. Early findings of a neurophysiological assessment of intercostal nerve injury during thoracotomy. Eur J Cardiothorac Surg 2002;21: Maguirea MF, Ravenscroftb A, Beggasa D, Duffya JP. A questionnaire study investigating the prevalence of the neuropathic component of chronic pain after thoracic surgery. Eur J Cardiothorac Surg 2006;29: Maguirea MF, Latterb JA, Mahajanb R, Beggasa D, Duffya JP. A study exploring the role of intercostal nerve damage in chronic pain after thoracic surgery. Eur J Cardiothorac Surg 2006;29: Steegers MA, Snik DM, Verhagen AF, Van der Drift MA, Wilder-Smith OH. Only half of the chronic pain after thoracic surgery shows a neuropathic component. J Pain 2008; 9: Editor s Note The author submitted a complete CONSORT checklist for a randomized controlled trial. Twenty-one of 22 topics were addressed and identified in the paper. The exception ancillary analyses is not relevant. This extra effort to obtain objectivity and credibility in meeting the comprehensive standards of the CONSORT checklist is applauded by the editor and sets a high standard for the rest of us.