One area which remains critically important to patient and procedural outcomes following spine surgery is the management of postsurgical pain. Providing adequate pain control in the first 24 to 48 hours, when postsurgical pain is known to be most intense, is paramount to the patient recovery experience, and particularly ambulation, which we know is essential to the rehabilitation process.
The current standard of care for pain management for a lumbar or cervical laminectomy includes a combination of opioid and non-opioid analgesia (epidural fentanyl, intravenous morphine patient-controlled analgesia [PCA], intramuscular NSAIDs) as well as medications to curb unintended opioid-related adverse events. The drawbacks of opioid-centric analgesic regimens are well-known, and range from sedation and confusion to gastrointestinal side effects, urinary retention and pruritus. In the case of spine surgery candidates, who often present in pain and may be on chronic opioid therapy, an opioid-based postsurgical pain management regimen may pose an increased risk for life-threatening opioid-related adverse events including oversedation and respiratory depression. Further, to ensure patient satisfaction, pre-op counseling is necessary to set realistic expectations about the level of pain management in the days following surgery.
According to published evidence1, inadequately-managed postsurgical pain could result in recurrent chronic pain in the long term, underscoring the need for safe, effective, and sustainable pain management solutions. Recently, a long-acting formulation of bupivacaine (EXPAREL® [bupivacaine liposome injectable suspension]), which is reported to provide up to 72 hours of pain control with reduced opioid requirements, has shown promise as the anchor to a multimodal pain management regimen.
As surgeons continue to work to maximize efficiency without compromising patient care, improving pain management protocols is of critical and increasing importance. As chief of spine surgery at a nonprofit, teaching and research hospital which is the largest provider of inpatient and outpatient services in New Jersey, I’m charged with evaluating and implementing cutting-edge protocols and best practices to optimize patient satisfaction, while improving hospital economic outcomes. My personal experience integrating EXPAREL into my postsurgical pain management protocol resulted in a strong reduction in opioid consumption — including the elimination of PCA for the majority of patients — and shorter patient stays in the post-anesthesia care unit (PACU).
To quantify the benefits of an EXPAREL-based multimodal pain management regimen, my team initiated a retrospective chart review among 19 cervical or lumbar laminectomy patients, to compare the effect of EXPAREL versus the current standard of care on postsurgical opioid consumption and PACU discharge readiness. Patients were either treated with EXPAREL (n=9) or the current standard of care, infiltration with bupivacaine HCl (n=10). In both groups, patients had access to morphine PCA for rescue analgesia as needed.
EXPAREL was administered in a circumferential fashion around the perimeter of the wound to create a surgical site field block. One 20 mL vial (266 mg) was diluted with 20 mL preservative-free normal sterile saline for a total volume of 40 mL. This was split among three layers as follows: 20 mL infiltrated in the fascial layers, and 20 mL infiltrated superficially into the subcutaneous tissue.
Overall, the consumption of opioids in the EXPAREL group was lower than observed in the standard of care group (9.8 mg vs. 13.36 mg); however, one patient in the EXPAREL arm of the study was identified as having been on a preexisting opioid regimen to control chronic back pain. When we adjusted the data to account for that patient’s baseline opioid consumption, the disparity between the EXPAREL and standard of care group was significantly greater — (6.9 mg vs. 13.93 mg). The notable impact of baseline opioid use on postsurgical opioid consumption suggests the importance of factoring in patient history when selecting a pain management regimen, setting expectations, and predicting outcomes. Additionally, the use of PCA for rescue analgesia was impressively lower in the EXPAREL group compared to the standard of care arm (22.22 percent vs. 50 percent), and in fact, 77.78 percent of EXPAREL patients avoided PCA rescue analgesia altogether.
We also evaluated the difference in PACU discharge readiness between the EXPAREL and standard of care group, since inadequate pain control and opioid rescue commonly result in PACU delays and backlogs, which can slowdown or close the operating room. Patients treated with EXPAREL were ready for discharge from PACU in about half the amount of time compared to patients receiving the standard of care (2.2 hours vs. 5 hours, respectively).
Based on these initial findings and my personal experience using EXPAREL in more than 30 cases — ranging from same-day laminectomy procedures to larger, inpatient one- and two-level fusion cases — a closer examination of the potential value of EXPAREL as an adjunct to the current standard of pain management following spine surgery may be warranted. While future studies may be required to quantify the impact of EXPAREL on patient-reported outcomes (satisfaction), and health economic outcomes (length and cost of stay), these retrospective results make a strong case for the use of EXPAREL in a multimodal, opioid-sparing approach to pain management for patients undergoing spine procedures.
1. Perkins FM, Kehlet, H. Anesthesiology 2000; 93:1123-33.