Prolonged Perioperative Use of Pregabalin and Ketamine to Prevent Persistent Pain after Cardiac Surgery.

BACKGROUND: Persistent postsurgical pain is common and affects quality of life. The hypothesis was that use of pregabalin and ketamine would prevent persistent pain after cardiac surgery. METHODS: This randomized, double-blind, placebo-controlled trial was undertaken at two cardiac surgery centers in the United Kingdom. Adults without chronic pain and undergoing any elective cardiac surgery patients via sternotomy were randomly assigned to receive either usual care, pregabalin (150 mg preoperatively and twice daily for 14 postoperative days) alone, or pregabalin in combination with a 48-h postoperative infusion of intravenous ketamine at 0.1 mg · kg · h. The primary endpoints were prevalence of clinically significant pain at 3 and 6 months after surgery, defined as a pain score on the numeric rating scale of 4 or higher (out of 10) after a functional assessment of three maximal coughs. The secondary outcomes included acute pain, opioid use, and safety measures, as well as long-term neuropathic pain, analgesic requirement, and quality of life. RESULTS: In total, 150 patients were randomized, with 17 withdrawals from treatment and 2 losses to follow-up but with data analyzed for all participants on an intention-to-treat basis. The prevalence of pain was lower at 3 postoperative months for pregabalin alone (6% [3 of 50]) and in combination with ketamine (2% [1 of 50]) compared to the control group (34% [17 of 50]; odds ratio = 0.126 [0.022 to 0.5], P = 0.0008; and 0.041 [0.0009 to 0.28], P < 0.0001, respectively) and at 6 months for pregabalin alone (6% [3 of 50]) and in combination with ketamine 0% (0 of 5) compared to the control group (28% [14 of 50]; odds ratio = 0.167 [0.029 to 0.7], P = 0.006; and 0.000 [0 to 0.24], P < 0.0001). Diplopia was more common in both active arms. CONCLUSIONS: Preoperative administration of 150 mg of pregabalin and postoperative continuation twice daily for 14 days significantly lowered the prevalence of persistent pain after cardiac surgery.

Persistent Postsurgical Pain Following Thoracotomy: A Comparison of Thoracic Epidural and Paravertebral Blockade as Preventive Analgesia.

OBJECTIVE: Persistent postsurgical pain (PPP) is common following thoracotomy. Thoracic epidural (TEB) and paravertebral blockade (PVB) are both established forms of perioperative analgesia for thoracotomy. There is currently a lack of data on their influence on PPP; this study aims to evaluate both techniques on PPP. DESIGN: Observational study, prospectively collected data. METHODS: Adults who underwent thoracotomy had either TEB or PVB for analgesia and were prospectively interviewed at six months. A numerical rating scale, the short form of the Leeds Assessment of Neuropathic Symptoms and Signs, and the EuroQol-5 dimension (EQ-5D) index were used to assess pain, neuropathic pain, and quality of life. RESULTS: Eighty-two patients who underwent a thoracotomy were recruited (TEB N = 36, PVB N = 46). Pain scores had a median (interquartile range [IQR]) of 1 (0 to 4.5) and 1.5 (0 to 4, P = 0.89), presence of PPP was 58.3% (95% confidence interval [CI] = 40.0-74.5%) and 60.9% (95% CI = 45.4-74.9%, P = 0.81), and presence of neuropathic pain was 30.6% (95% CI = 16.3-48.1%) and 28.2% (95% CI = 16.0-43.5%, P = 0.85). Reported quality of life was 0.71 (0.14-0.85) and 0.80 (0.19-0.91, P = 0.21). Patients who had PPP reported worse quality of life measures compared with those who were pain free, with a median (IQR) EQ-5D index of 0.69 (-0.15 to 0.85) and 0.85 (0.72 to 1, P = 0.0007); quality of life was worst when there was a neuropathic component (median = 0.39, IQR = -0.24 to 0.75). CONCLUSIONS: There was no statistical difference in the development of persistent postsurgical pain between patients who received a TEB or a PVB; however, patients who developed PPP had a significantly lower quality of life, which was worse with a neuropathic component.

Opioid-Based Anesthesia and Analgesia for Adult Cardiac Surgery: History and Narrative Review of the Literature.

Opioids have played in a key role in cardiac anesthesia and analgesia since the early years of cardiac surgery. Today, opioids continue to be the primary mode for analgesia in cardiac surgery, yet there is considerable variability in the choice, dose and route of used. A history of the use of opioids in cardiothoracic anesthesia is presented, followed by an examination of the differences among current opioids in use and of outcome variables important in cardiac anesthesia, such as postoperative analgesia, extubation times, fast-track cardiac anesthesia, chronic neuropathic pain, and cardioprotection. Topical issues such as the role of perioperative opioid use in the global opioid crisis, opioid-sparing techniques and novel opioids in development are also discussed.