Opioid–free Anesthesia Found to Improve Pain Control After Surgery

People with Ehlers-Danlos syndrome (EDS) who undergo surgery to fix joint problems experience less pain when given opioid-free anesthesia and post-surgery pain management, a study reports.

The study, “Opioid-free anesthesia for patients with joint hypermobility syndrome undergoing craneo-cervical fixation: a case-series study focused on anti-hyperalgesic approach,” was published in the Orphanet Journal of Rare Diseases.

A common feature of EDS is joint hypermobility — also called joint hypermobility syndrome — a condition defined by larger-than-normal range of motion in one or more joints. In EDS patients, this can affect the ligaments that connect the skull to the spine, leading to a condition called cranio-cervical instability.

Instability in the cervical spine can lead patients to experience alterations to vision, hearing, and speech as well as swallowing, among other symptoms. EDS patients with cranio-cervical instability often have widespread pain, which is hard to manage and often not controlled by opioids, a type of medicine used for pain relief but has serious side effects, including addiction.

Cranio‐cervical fixation is a surgical procedure used to realign and immobilize the connection between the head and neck. To improve patient recovery after surgery, new protocols have been developed that include opioid-free anesthetics (OFA).

In the study, researchers in Spain conducted a case-series investigation (NCT04437589) to assess whether OFA together with powerful analgesics (OFA-plus) lessened postoperative pain and helped reduce the need for opioids compared with opioid-based anesthesia (OP) in EDS patients who underwent cranio-cervical fixation surgery from September 2018 to March 2020.

In total, 42 EDS patients with joint hypermobility syndrome were enrolled in the study (39 women and three men). The OFA-plus group included 19 patients and the OP group had 23. All patients were of similar body composition (according to their body mass index, a measure of body fat) and showed no differences in their pain levels before surgery, as assessed using a visual analogue score (VAS).

In the OFA-plus intervention group, patients received intravenous (directly into the blood) opioid-free anesthesia composed of a combination of lidocaine (local anesthetic), ketamine (general anesthesia), and dexmedetomidine (sedative), together with propofol (a sedative-hypnotic agent to help relax the patient before general anesthesia). Those in the OP group received a opioid-based anesthesia (a combination of fentanil, remifentanil, or sufentanil) with propofol.

Postoperative management remained opioid-free in the OFA-plus group, while morphine infusions were administered in the OP group. In both groups, methadone was administered whenever severe pain occurred.

After surgery, VAS scores showed a significant reduction from day one to day six in patients in the OFA-plus group compared to the OP group. This reduction in pain scores was more evident immediately after surgery (day one), with a 32% reduction in the OFA-plus group.

The length of hospital stay was similar between groups — mean average of 19 days in the OFA-plus vs. 22 days in the OP group.

While 95% of those in the OP group required methadone, an opioid used for pain crises, such treatment was required by 22% of those in the OFA-plus group. Moreover, in the OP group, 42% of patients required high doses of methadone (over 15 mg/day) to manage postoperative pain.

The team also reported that in the first day after surgery, the need for another opioid analgesic, sufentanil, was significantly reduced in patients in the OFA-plus group compared with the OP group.

Patients in the OFA-plus group experienced less nausea, vomiting, and ileus (lack of movement in the intestines). No difference in constipation incidence was seen between groups.

The OFA-plus group also showed a 77% reduction in anxiolytic (anti-anxiety medicine) use. In contrast, 63% of patients in the OP group required frequent administration of anxiolytics (over three times a day).

Also, over 60% of the OFA-plus patients decreased their need for opioids after discharge from the hospital, while no changes were observed in patients in the OP group. Four patients (17.4%) in the OFA-plus group experienced visual hallucinations.

Overall, the results showed that “OFA‐plus management decreases the total doses of methadone rescues, reduces anxiolytic requirements and gastrointestinal side-effects, except for constipation,” the researchers wrote.

Opioid‐free anesthesia is therefore a “feasible option to improve postoperative pain control, reducing the opioids’ use and their postoperative side‐effects” in EDS patients who undergo craneo‐cervical fixation surgery, they concluded.