The study, conducted at Georgetown Surgery Center in Georgetown, Texas, followed 20 consecutive orthopedic surgery patients managed under the center’s Acute Pain Management Program with multimodal opioid-sparing analgesia. Data were collected during an initial pump trial period from August 21 to September 8, 2025, representing the first clinical use of the Avoset infusion pump, manufactured by Eitan Medical, at the institution. The authors emphasize that the work was a feasibility assessment of implementing smart infusion pump technology for ambulatory perineural analgesia in routine clinical practice, not a comparison against other pumps or analgesic strategies.

All patients received continuous peripheral nerve catheters placed under ultrasound guidance by an attending anesthesiologist, with the approach matched to the surgical site: interscalene brachial plexus catheters for shoulder and upper limb procedures, and adductor canal saphenous nerve catheters, with or without supplemental iPACK blocks, for lower limb procedures. Before surgery, each patient received non-opioid oral analgesics consisting of 1,000 mg of acetaminophen, 200 mg of celecoxib, and 300 mg of gabapentin. In the operating room, under general anesthesia, patients received an initial 20 mL nerve block of 0.5% ropivacaine, followed after surgery by a continuous infusion of 0.2% ropivacaine through the pump at a basal rate of 8 mL per hour, with 3 mL patient-controlled boluses subject to a 30-minute lockout, drawn from a 500 mL reservoir.

The pump was pre-programmed using a dedicated programming tool, with the preset program sent to the device via Bluetooth and near-field communication. Preset programs are intended to minimize manual entry errors and ensure standardized therapy. The device also transmits data through a mobile app to a web-based platform that displays pump event data, including bolus attempts, alarm logs, and drug delivery records, enabling remote review by clinicians. In this study, that connected data supported a support hotline on one occasion; a more detailed assessment of the remote monitoring capability is planned as a separate, dedicated technology evaluation.

Postoperative care followed a standardized opioid-sparing template. Every patient was prescribed opioids totaling up to 112.5 morphine milligram equivalents (MME) over three days, with a choice among oxycodone 5 mg tablets, oxycodone/acetaminophen combination tablets, or hydromorphone 1.5 mg tablets, capped at five tablets per 24-hour period. All patients also received concurrent non-opioid analgesics, either ibuprofen 600 mg every six hours as needed or naproxen 500 mg twice daily as needed, and were instructed to use opioids only when non-opioid medications provided inadequate relief and to stop opioids once pain was controlled without them. Patients were either opioid naive or had minimal prior opioid exposure; no opioid-tolerant patients were included.

Nurses conducted structured phone follow-up on postoperative days 3 through 6, recording whether pain was controlled or uncontrolled, whether the nerve catheter was intact, the number and name of opioids taken, and any pertinent clinical information. Opioid consumption was self-reported and therefore subject to recall bias, and pain adequacy was captured only as a binary outcome rather than on a validated intensity scale. Analysis was purely descriptive, with no inferential statistical testing; quartiles were calculated by linear interpolation and proportions were reported with 95% confidence intervals using the Wilson score method.

Across the cohort, postoperative opioid consumption over three days was low, with a median of 15 MME (interquartile range 0–39.4 MME, range 0–90 MME). Forty percent of patients, 8 of 20, reported using no opioids at all. The cohort was procedurally heterogeneous: twelve patients underwent shoulder surgery, three anterior cruciate ligament reconstruction, two popliteofibular ligament repair, and one each total knee arthroplasty, humerus fracture, and thumb surgery. Shoulder surgery patients receiving interscalene brachial plexus catheters had a median consumption of 15 MME (interquartile range 0–45 MME, range 0–90 MME), with 42%, or 5 of 12, using no opioids. The three ACL reconstruction patients receiving adductor canal blocks had a median consumption of 0 MME (range 0–22.5 MME), with two of three reporting no opioid use. Patients undergoing other procedures, including total knee arthroplasty, popliteofibular ligament repair, and humerus fracture, had a median consumption of 41.25 MME (range 7.5–52.5 MME), and the thumb surgery patient reported no opioid use. The authors note that these figures compare favorably with published benchmarks, such as average shoulder surgery consumption of 82.5 to 112.5 MME with regional anesthesia, but they caution that the low consumption reflects the multimodal opioid-sparing protocol as a whole, with the pump playing a supporting role in reliable home delivery rather than acting as an independently proven driver of opioid reduction.

Pump performance was the study’s central feasibility question, and the results were consistent. Seventeen of 20 patients, 85% (95% confidence interval 64.0%–94.8%), completed the full programmed infusion. The three early discontinuations, 15% (95% confidence interval 5.2%–36.0%), were attributable entirely to catheter dislodgement or pullout, a known complication of peripheral nerve catheters, and not to any pump malfunction or failure. A total of seven alarm events occurred: two air-in-line alarms requiring repriming of the administration set, two occlusion alarms, one caused by tubing kinking and one by a patient lying on the tubing, one new-bag notification at completion of the programmed volume, and two infusion-complete notifications on empty bags. All alarms were resolved by patients at home within an hour, without interrupting therapy beyond a short troubleshooting delay, and the support hotline was contacted only once. The authors argue that this alarm functionality represents a potential advantage over elastomeric pumps, which generally lack alarms and cannot notify users of interrupted flow or occlusion, and that electronic pumps can additionally offer automated boluses, delayed start timers, and more precise dosing while being less susceptible to flow variation from reservoir height, temperature, or back pressure.

The study’s limitations are substantial and the authors enumerate them candidly. The sample was small, single-center, and retrospective, with no comparator group such as an elastomeric pump or alternative analgesic strategy, precluding causal conclusions. The cohort was procedurally heterogeneous, opioid consumption was self-reported by phone survey, pain was recorded only as controlled or uncontrolled, and patients were managed within a structured opioid-sparing program, introducing potential selection bias. Post-discharge device data were not systematically analyzed because remote monitoring was not a predefined endpoint, and the study was not designed to evaluate long-term opioid use, functional recovery, or cost-effectiveness. Catheter dislodgement occurred in three cases, consistent with previously reported rates in the range of 15% for perineural catheters, though the prevalence of displacement specifically in the home environment has not been established.

Within those constraints, the authors conclude that a smart electronic infusion pump reliably delivered opioid-sparing perineural analgesia in ambulatory and home settings following orthopedic surgery, with no pump-related discontinuations and successful patient management of alarms. They call for future prospective studies with larger cohorts and comparator arms, including direct comparisons with elastomeric pumps, to evaluate clinical effectiveness and generalizability, and for research into how remote infusion data and alarm analytics can be integrated into postoperative follow-up workflows. For now, the series stands as an early, cautiously framed signal that connected electronic infusion systems can support home-based nerve-block analgesia as part of a broader effort to reduce perioperative opioid exposure.

Subject of Research: Feasibility of a smart connected electronic infusion pump for home-based opioid-sparing perineural analgesia after orthopedic surgery

Article Title: A retrospective case series and technological review of post-surgical analgesia for orthopedic surgery using a smart connected infusion pump: an opioid-sparing protocol

Article References: Nelson, D., Brand, J., Rubio, V., & Lester, A. (2026). A retrospective case series and technological review of post-surgical analgesia for orthopedic surgery using a smart connected infusion pump: an opioid-sparing protocol. Frontiers in Pharmacology, 17, 1838931. https://doi.org/10.3389/fphar.2026.1838931

Image Credits: AI Generated

DOI: 10.3389/fphar.2026.1838931

Keywords: opioid-sparing analgesia, continuous peripheral nerve block, infusion pump, orthopedic surgery, regional anesthesia, ambulatory care, home infusion, ropivacaine, retrospective case series, pump alarms, catheter dislodgement, multimodal analgesia