Study of the Effect of the Drug Gabapentin on Postoperative Pain and Incidence of Postoperative Nausea and Vomiting
Condition: Obesity, Morbid; Postoperative Pain; Postoperative Nausea and Vomiting
MeSH terms: Obesity, Morbid; Pain, Postoperative; Nausea; Vomiting; Postoperative Nausea and Vomiting
Study type: Interventional

Summary: 
      The purpose of this research study is to evaluate the drug gabapentin (Neurontin®) for its
      ability to reduce postoperative pain, the need for morphine-like pain medication, and the
      severity and frequency of postoperative nausea and vomiting in laparoscopic gastric bypass
      surgery patients.
    

Detailed description: 
      The occurrence of morbid obesity is at epidemic proportions in the United States.
      Laparoscopic gastric bypass is an effective means of safely facilitating patient weight loss
      and thereby drastically reducing the prevalence and severity of many future health
      complications [1]. However, managing morbidly obese surgical patients poses certain obstacles
      for anesthesiologists, including a high incidence of obstructive sleep apnea [2].

      Laparoscopic gastric bypass, like all surgical interventions, has associated postoperative
      challenges including pain management and prevention/control of postoperative nausea and
      vomiting. To assure the highest patient satisfaction, all areas of patient comfort must be
      addressed. However, with pain management in morbidly obese patients, caution must be used
      when administering opioids, as they can have an increasing effect of respiratory depression
      in patients already at risk due to obstructive sleep apnea [3]. Gastric bypass is also
      associated with a significant incidence of protracted postoperative nausea and vomiting [4].
      Therefore, regimens that address both patient safety and patient comfort are desired.

      Gabapentin (Neurontin) is an alkylated analog of the inhibitory neurotransmitter
      gamma-aminobutyric acid (GABA) that has been FDA approved for the treatment of seizures,
      headaches fibromyalgia and chronic neuropathic pain due to various etiologies [5]. Many
      randomized controlled trials have been performed with perioperative gabapentin [6-10]. The
      effect of perioperative administration of gabapentin on postoperative pain and opioid
      consumption has been extensively studied and several meta-analyses have been published in the
      last several years examining to overall findings of these studies. The general consensus is
      that gabapentin has anti-hyperalgesic and opioid-sparing properties and may also reduce the
      incidence of postoperative nausea and vomiting [5, 11-15]. Most research has shown that
      gabapentin is beneficial in the treatment of postoperative pain, but some show neither
      positive nor negative effects. There has been no evidence that gabapentin is detrimental or
      poses any risks to the postoperative patient. However, gabapentin has not been specifically
      studied in bariatric surgery. Therefore, the purpose of this study is to explore the
      hypothesis that perioperative gabapentin has anti-hyperalgesic and opioid-sparing properties,
      thus increase patient comfort and satisfaction by decreasing pain scores and reducing the
      adverse effects of opioids, such as postoperative nausea and vomiting.

      This is a randomized, double-blind and placebo controlled study, which will be performed in
      adult laparoscopic gastric bypass patients coming to surgery for morbid obesity. The major
      end-points of analyses are intraoperative and postoperative opioid requirements and the
      incidence of nausea and vomiting in the postoperative period.
    

Intervention name(s): Gabapentin; Placebo; Gabapentin
Intervention type(s): Drug; Drug; Drug
Intervention description(s): Gabapentin 1200 mg (24 cc) by mouth 1 hour prior to surgery AND Gabapentin 300 mg (6cc) by mouth x 6 doses after surgery (0800PM the evening of surgery, 0800AM postoperative day 1, 0200PM postoperative day 1, 0800PM postoperative day 1, 0800AM postoperative day 2, 1200PM postoperative day 2); Placebo 1200 mg (24 cc) by mouth 1 hour prior to surgery AND Placebo 300 mg (6cc) by mouth x 6 doses after surgery (0800PM the evening of surgery, 0800AM postoperative day 1, 0200PM postoperative day 1, 0800PM postoperative day 1, 0800AM postoperative day 2, 1200PM postoperative day 2); Gabapentin 1200 mg (24 cc) by mouth 1 hour prior to surgery AND Placebo 300 mg (6cc) by mouth x 6 doses after surgery (0800PM the evening of surgery, 0800AM postoperative day 1, 0200PM postoperative day 1, 0800PM postoperative day 1, 0800AM postoperative day 2, 1200PM postoperative day 2)
Intervention MeSH terms: Gabapentin
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Gastric Bypass; Gabapentin; Postoperative Nausea and Vomiting; Analgesics, Opioids; Sleep Apnea, Obstructive; Respiratory Depression; Oximetry