Intraperitoneal aerosolization of bupivacaine is a safe and effective method in controlling postoperative pain in laparoscopic Roux-en-Y gastric bypass

ORIGINAL RESEARCH Intraperitoneal aerosolization of bupivacaine is a safe and effective method in controlling postoperative pain in laparoscopic Roux-en-Y gastric bypass Nawar A Alkhamesi 1 James M Kane, Jr 2 Paul J Guske 2 Jonathan W Wallace 2 Peter C Rantis, Jr 2 Department of Biosurgery and Technology, Imperial College London, UK; 2 Department of Surgery, Alexian Brothers Hospital Network, Chicago, USA 1 Introduction: Obesity is a worldwide problem and has grown in severity in the last few decades making bariatric surgery and, in particular, laparoscopic banding and Roux-en-Y gastric bypass efficacious and cost-effective procedures. The laparoscopic approach has been shown to offer significant healthcare benefits, of particular interests are reports of decreased postoperative pain resulting in a shorter hospital stay and an earlier return to normal activity. However, many patients still experience significant pain, including shoulder tip pain, that require strong analgesia including opiates during their early recovery period. The aims of this study were to establish the safe use of the aerosolization technique in bariatric surgery and to investigate the possible benefits in reducing postoperative pain. Methods: In this study, fifty patients undergoing laparoscopic gastric bypass were recruited and divided into two groups; control (n = 25) and therapeutic (n = 25). The control group received intraperitoneal aerosolization of 10 mL of 0.9% normal saline while the therapeutic group received 10 mL of 0.5% bupivacaine. All the patients had standard preoperative, intraoperative, and postoperative care. Pain scores were carried out by the nursing staff in recovery and 6 h, 12 h and 24 h postoperatively using a standard 0–10 pain scoring scale. In addition, opiate consumption via patient-controlled analgesia (PCA) was recorded. Results: Aerosolized bupivacaine reduced postoperative pain in comparison to normal saline (p ⬍ 0.05). However, PCA usage showed no statistically significant change from the control group. Conclusion: The aims of this study were achieved and we were able to establish the safe use of the aerosolization technique in bariatric surgery and its benefits in reducing postoperative pain. Keywords: laparoscopy, aerosolization, Roux-en-Y gastric bypass, bupivacaine, local anesthetic, intraperitoneal therapeutics Introduction Correspondence: Nawar A Alkhamesi Department of Biosurgery and Technology, Imperial College London, 10th Floor, QEQM Wing, St. Mary’s Hospital, Praed Street, London W2 1NY, UK Tel +44 20 7886 6119 Fax +44 20 7886 1810 Email Obesity is a worldwide problem and has grown in severity in the last few decades (Elder and Wolfe 2007). This disease will have a significant impression on patients’ health and the economy making bariatric surgery and in particular laparoscopic banding (LAGB) and Roux-en-Y gastric bypass (LRYGB) efficacious and cost-effective procedures (Frezza et al 2007; Hawkins et al 2007). The laparoscopic approach has been shown to offer significant health care benefits, of particular interest are reports of decreased postoperative pain resulting in a shorter hospital stay and an earlier return to normal activity. However, many patients still experience significant pain, including shoulder tip pain, that require strong analgesia including opiate during their early recovery period (Dixon et al 2005; Madan et al 2005). Journal of Pain Research 2008:1 9–13 © 2008 Alkhamesi et al, publisher and licensee Dove Medical Press Ltd. This is an Open Access article which permits unrestricted noncommercial use, provided the original work is properly cited. 9 Alkhamesi et al Intraperitoneal anesthetics have been studied in LRYGB and the results showed a noticeable reduction in narcotic use with no clear effect on postoperative pain (Symons et al 2007). This finding emphasizes the fact that post-laparoscopic pain is a multifactorial phenomenon and requires a global approach. The author (NA Alkhamesi) has been involved in developing an aerosolization system that utilizes the unique laparoscopic environment, a closed and pressurized system, to deliver intraperitoneal medications in an aerosol form, which will guarantee the uniform coverage of the entire peritoneal cavity in order to achieve maximum therapeutic benefits (Alkhamesi et al 2005). This technology has been shown to be successful in the treatment of post-laparoscopic pain following laparoscopic cholecystectomy using an aerosolized bupivacaine (Alkhamesi et al 2007). The aims of this study were to establish the safe use of the aerosolization technique in bariatric surgery and to investigate the possible benefits in reducing postoperative pain. Material and method This is a prospective randomized double-blinded clinical trial that was approved by the Institutional Review Board and was carried out at Alexian Brothers Hospital Network, Chicago, USA. All the patients gave informed consent and were provided with an information booklet, which described the study in detail along with the possible risk factors. Patient selection We recruited 50 patients on a voluntary basis who underwent elective laparoscopic Roux-en-Y gastric bypass (LRYGB) at the Alexian Brothers Hospital, Chicago, USA The inclusion criteria included patients between the age of 18–65 years, and American Society of Anesthesiology (ASA) scores I, II, and III. We excluded patients below the age of 18 and those with known allergies to bupivacaine or any other drugs used during anesthesia or in the postoperative pain management protocol. We also excluded patients with ASA IV, patients with history of drug abuse, and those who used narcotic drugs within 30 days of their procedure. Study design All the patients, junior medical staff and the nursing staff in recovery and the wards were blinded to the study. The operating surgeons and the anesthetist were aware of the study protocol, but were blinded to contents of the aerosol or the injected solutions. The 50 patients were randomly divided into 2 groups of twenty-five; the Control group 10 (received 10 mL of aerosolized intraperitoneal 0.9% normal saline), and the Treatment group (received 10 mL, equivalent to 50 mg of aerosolized 0.5% plain bupivacaine). The two groups had the same anaesthetic protocol. Pre-operatively patients received fentanyl 50–100 μg/kg and midazolam 0.07 mg/kg intravenously. Anesthetic induction was achieved by using 1 μg/kg fentanyl and propofol 2–3 mg/kg. Perioperatively, the patients received a mixture of air and oxygen with sevoflurane to maintain anesthesia, in addition, pre-incision 50 μg/kg of morphine was given intravenously. Muscle relaxation was achieved using 0.5 mg/kg rocuronium. Experienced laparoscopic surgeons (JK, PG, JW, and PR), using the same surgical technique standardized by the Department of Surgery at the Alexian Brothers Hospital, performed the operations. A classic 6-ports procedure was utilized to perform the operation. 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