Postoperative Pain Management

Postoperative pain management presents a major challenge to patients and health care providers. Inadequate pain management can lead to delays in rehabilitation and hospital discharge as well as lower patient satisfaction. According to the National Institute of Medicine, more than 805 patients experience postoperative pain, with fewer than 50% receiving adequate pain management.¹

Nociception and pain involve complex neurohormonal signaling pathways. Despite advances in the understanding of postoperative pain, including the need for a multimodal approach, opioid monotherapy remains common as initial, first-line pain management, despite known risks such as oversedation and long-term dependence and abuse associated with opioid use. Opioid-related adverse events have been shown to be associated with increased hospitalization costs and an increase in the overall length of hospital stay.²

The use of multimodal treatment strategies in the management of postoperative pain has been explored in a variety of surgical fields. Treatment with multimodal analgesia has been shown to reduce opioid use, reduce the incidence of opioid-associated adverse events, and improve pain control when compared with using opioid monotherapy.^3-5 Non-opioid analgesic options include acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), local anesthetics, gabapentinoids, ketamine, and glucocorticoids. The most well studied combination of non-opioid analgesics includes acetaminophen with NSAIDs.⁶ Other combinations of non-opioid analgesics are not well studied, and most non-opioid analgesic options are also associated with particular adverse effects as well.⁷

Another mode of postoperative pain management involves the use of regional anesthetic techniques including epidural and perineural and local anesthetics. Epidural analgesia involves the injection of a local anesthetic such as bupivacaine with or without an opioid such as fentanyl into the epidural space within the spinal column. It has traditionally been used in various thoracic, abdominal, and gynecological surgeries. Epidural analgesia is not without risks, including the development of epidural hematoma and abscesses.⁸ Perineural nerve blocks can be used to inject anesthetics into areas adjacent to the nerve or plexus of various locations depending on the type of surgery performed. A 2006 meta-analysis found that use of peripheral nerve blocks was associated with better pain management and a reduction in opioid-associated adverse events compared with opioid monotherapy in postoperative pain management.⁹ A potential disadvantage of epidural and perineural techniques is the requirement of intra- and postoperative management of the drug delivery catheter, and that it is contraindicated in patients taking antiplatelet or anticoagulant medications as well as individuals with coagulopathies. Nevertheless, they represent a potential strategy for optimizing pain management and limiting opioid use postoperatively.

Case

EK is a 30-year-old male with a past medical history significant for posttraumatic stress disorder and polysubstance abuse who presented as a red trauma after being involved in a motor vehicle accident. His injuries were significant for bilateral rib fractures (right 1-12, left 1-8), bilateral hemopneumothoraxes with pulmonary contusions, and cerebral contusions with questionable traumatic subarachnoid hemorrhage and subdural hemorrhage. During his hospital course, management of his pain and agitation was a significant issue. By hospital day 10, the patient was receiving hydromorphone 5 mg per hour, dexmedetomidine 1.2 mcg/kg per hour, lorazepam 1 mg every 8 hours, oxycodone 15 mg every 4 hours, acetaminophen 1000 mg every 6 hours, gabapentin 300 mg every 8 hours, and lidocaine patches with uncontrolled pain and sedation. The patient was scheduled for rib plating; however, there was significant concern regarding management of postoperative pain. The decision was made to place an epidural catheter prior to his surgical procedure. He was initiated on bupivacaine 0.125% at 8 ml per hour. EK’s operative procedure proceeded without complication. He was extubated on postoperative day 2, at which time he received a patient-controlled analgesia, and his epidural was removed on postoperative day 3.

Discussion

Given the extent of EK’s injuries, as well as his underlying substance abuse disorder, management of his pain, agitation, and withdrawal with opioids alone would not have been reasonable. Initially, multimodal pharmacotherapy involving opioids, gabapentinoids, NSAIDs, and acetaminophen was attempted. However, this strategy did not sufficiently manage EK’s pain. Although multimodal systemic therapy did not completely control EK’s pain, it was still a reasonable choice in an effort to decrease opioid use and opioid-related adverse events.

An epidural was used in this case, as EK had extensive bilateral injuries and did not have any contraindications to epidural use such as coagulopathy or antiplatelet/anticoagulant use. Use of a peripheral nerve block may have been a reasonable alternative. EK did not have any complications associated with his epidural use. However, it is important to weigh the risks and benefits of regional analgesics for each patient.

Postoperative pain management is a complicated topic and requires an individualized approach depending on patient characteristics, the type of surgery performed, and the expected course of postoperative recovery.

ELLEN HUANG, PHARMD, is the cardiothoracic and surgical ICU clinical specialist at Augusta University Medical Center.PHILLIP S. OWEN, PHARMD, BCPS, practices as the cardiothoracic intensive care unit clinical pharmacy specialist at the University of North Carolina Medical Center. He also is a member of the inpatient lung transplant and thoracic and vascular surgery services.

References

• Institute of Medicine. Relieving pain in America: A blueprint for transforming prevention, care, education, and research nationalacademies.org/hmd/Reports/2011/Relieving-Pain-in-America-A-Blueprint-for-Transforming-Prevention-Care-Education-Research.aspx. Published June 2011. Accessed July 27, 2017.
• Oderda GM, Said Q, Evans RS, et al. Opioid-related adverse drug events in surgical hospitalizations: impact on costs and length of stay. Ann Pharmacother. 2007;41(3):400-6.
• Rafiq S, Steinbruchel DA, Wanscher MJ, et al. Multimodal analgesia versus traditional opiate based analgesia after cardiac surgery, a randomized controlled trial. J Cardiothorac Surg. 2014;9:52. doi: 10.1186/1749-8090-9-52.
• Lee SK, Lee JW, Choy WS. Is multimodal analgesia as effective as postoperative patient-controlled analgesia following upper extremity surgery? Orthop Traumatol Surg Res. 2013;99(8):895-901. doi: 10.1016/j.otsr.2013.09.005.
• Rajpal S, Gordon DB, Pellino TA, et al. Comparison of perioperative oral multimodal analgesia versus IV PCA for spine surgery. J Spinal Disord Tech. 2010;23(2):139-14 doi: 10.1097/BSD.0b013e3181cf07ee.
• Hyllested M, Jones S, Pedersen JL, Kehlet H. Comparative effect of paracetamol, NSAIDs or their combination in postoperative pain management: a qualitative review. Br J Anaesth. 2002;88(2):199-214.
• Mathiesen O, Wetterslev J, Kontinen VK, et al. Adverse effects of perioperative paracetamol, NSAIDs, glucocorticoids, gabapentinoids and their combinations: a topical review. Acta Anaesthesiol Scand. 2014;58(10):1182-1198. doi: 10.1111/aas.12380.
• Paul JE, Buckley N, McLean RF, et al. Hamilton acute pain service safety study: using root cause analysis to reduce the incidence of adverse events. Anesthesiology. 2014;120(1):97-109. doi: 10.1097/ALN.0b013e3182a76f59.
• Richman JM, Liu SS, Courpas G, et al. Does continuous peripheral nerve block provide superior pain control to opioids? A meta-analysis. Anesth Analg. 2006;102(1):248-257.
• Mei S, Jin S, Chen Z, et al. Analgesia for total knee arthroplasty: A meta-analysis comparing local infiltration and femoral nerve block. Clinics (Sao Paulo). 2015;70(9):648-53. doi: 10.6061/clinics/2015(09)09.