An interventional study of ambIT pump with catheter and ambIT pump with sham catheter in Chronic Pain, Opioid Use and Adductor Canal Block, sponsored by Hospital for Special Surgery, New York. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-09-03.
Sponsored by Hospital for Special Surgery, New York · Not applicable, Interventional, and Other
The goal of this interventional clinical trial is to assess opioid consumption 24-48 hrs post anesthesia block among patients undergoing total knee arthroplasty. The main question it aims to answer is:
1. Is there a difference in opioid consumption 24-48 hours post block administration among patients that receive an adductor canal catheter (ACC) versus adductor canal block (ACB)?
Participants will be:
The purpose of this study is to see if adding a continuous ACB catheter will extend analgesia beyond the 24-48 hour period. This interventional clinical trial will assess opioid consumption in patients undergoing total knee arthroplasty 24 to 48 hours after anesthesia block. Rebound pain is a well-known phenomenon in which patients experience severe pain immediately after the nerve block is removed. It is also known that by extending the duration of analgesia, you can reduce or prevent rebound pain. Motor sparing compartment blocks have transformed patients' ability to participate in rehabilitation earlier than ever before, even ambulating on POD 0. Thus, by extending analgesia and encouraging early ambulation, adductor canal catheters are likely to not only reduce opioid consumption but also allow for earlier discharge. The two "hot" themes in recent total knee replacement analgesia pathways are not only providing an effective Enhanced recovery after surgery (ERAD) protocol, but also combating the opioid epidemic through regional anesthesia and non-opioid multimodal pathways. This study will assist in determining which modality is superior (single shot blocks with additive versus catheter) and will introduce a novel method of following patients at home via a transitional pain service (telemedicine). This research will further investigate chronic pain 6 months after surgery.
Patients in the intervention group will have a catheter that continuously infuses numbing medication into their operative leg for 50 hours (up to POD 3). It is hypothesized that the patient will have better pain control, mobility, and less rebound pain, which is common following POD 1. By infusing the catheter with a disposable single use ambIT system (Summit Medical Products), all patients enrolled in the intervention group (ACC) will have the same amount running continuously, allowing the patient to be discharged with the catheter in place before the 50-hour infusion is completed. Prior to discharge, patients will be instructed on how to remove the catheter and will be able to download the Smartphone app "Diagnotes" at the hospital. While the catheter is in place, the Diagnotes app (a HIPPA-compliant text messaging service) will be the patient's primary means of communication with the pain doctor at home.
Patients in the control group will have a sham (fake) catheter attached to their operative leg for 50 hours. Patients will also be instructed on how to remove the catheter prior to discharge and will be able to download the Smartphone app "Diagnotes" in the hospital. While the catheter is in place, the Diagnotes app (a HIPPA-compliant text messaging service) will be the patient's primary means of communication with the pain doctor at home.
Researchers will contact both groups for follow-ups for up to 6 months.
2,930 studies on the registry are indexed under Chronic Pain; 701 are open to participants now.
This study's planned enrollment of 64 is close to the median of 60 across 2,161 interventional studies indexed under Chronic Pain.
Browse Chronic Pain studies →Hospital for Special Surgery, New York is the lead sponsor of 217 studies on the registry; 39 are open to participants now.
Of its 27 completed or terminated interventional studies of FDA-regulated products, 20 (74%) have results posted.
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Exclusion Criteria:
Patients will received the an adductor canal catheter that continuously infuses numbing medication to their operative leg for 50 hours post-surgery. Patients will also communicate with their pain doctor via the Diagnotes application while the catheter is in place.
Device: ambIT pump with catheter
Patients will received the a sham adductor canal catheter that is attached to their operative leg for 50 hours post-surgery. Patients will also communicate with their pain doctor via the Diagnotes application while the catheter is in place.
Device: ambIT pump with sham catheter
0.2% ropivacaine will be infused through a catheter pump at a rate of 10 ml/hr, 600 ml reservoir.
sham catheter with no infusion
Opioid consumption at 24-48 hours
The cumulative opioid consumption 24-48 hours post block administration. Measured in morphine milligram equivalents per day. Although collected over a period of time, the total amount will be summed and the average will be reported.
Time frame: from 24 hours to 48 hours
Opioid consumption at 72 hours, 96 hours, and 1 week
The cumulative opioid consumption 72hours, 96 hours, and 1 week post block administration. Measured in morphine milligram equivalents per day. Although collected over a period of time, the total amount will be summed and the average will be reported.
Time frame: 72 hours to 1 week
Numerical Pain Rating Score
Patients are asked to give a number between 0 and 10 that best fits their pain intensity. The scale is 0 = 'no pain at all' whereas 10 = 'the worst pain ever possible'. Measured at multiple time points: DOS, post-operative day (POD) 1, POD 2, POD 3, POD 4, POD 7, \& POD 60
Time frame: Day of surgery to post operative day (POD) 60
Physical Therapy Milestones
Collected from the physical therapy notes. This outcome will assess for time to ambulation (measured in distance traveled, stairs, time of ambulating \> 30 meters, and reaching discharge criteria).
Time frame: post operative day (POD) 1 up to POD 4
Patient Satisfaction with Pain Control
Patients are asked to report on their satisfaction with pain control on a scale of 0 to 10, with 0 = extremely dissatisfied and 10 = extremely satisfied.
Time frame: post operative day (POD) 1, 2, 4 & 60
Hospital Length of Stay
From when the patient is in the PACU to when the patient has been discharged from the hospital. PACU time = "PACU Transfer In" and Discharge time = "Discharge"
Time frame: up to 7 days after the day of surgery
Opioid Related Symptom Distress Scale (ORSDS)
The Opioid-Related Symptom Distress Scale (ORSDS) is a 4-point scale that evaluates 3 symptom distress dimensions (frequency, severity, bothersomeness) for 12 symptoms. The symptom-specific ORSDS is the average of the 3 symptom distress dimensions. The composite ORSDS is the average of 12 symptom-specific scores.
Time frame: after the surgery end time, on post operative day (POD) 1, 4, and 60
Number of participants who experienced Buckling/Falls/Quadricep during physical therapy
Whether a participant experiences buckling, falls, or quadricep weakness during physical therapy, precluding ambulation.
Time frame: On post operative day (POD) 1, 2, 3, 4
Incidents of participants experiencing a blood loss during surgical procedure
Whether the participant experienced any blood loss during their surgical procedure. Measured in binary responses (yes/no).
Time frame: During surgery
Block resolution
The patient will be asked in the morning of POD 1 when they feel the block has worn off, and in the evening of POD 3 after the catheter has been removed.
Time frame: Up to post operative day 3
Distance of ambulation
The total distance of ambulation during physical therapy while the patient is inpatient, collected from the physical therapy notes.
Time frame: post operative day (POD) 0,1,2,3,4
Catheter related complications
Patient will be asked if they have experience any of the following with regards to the catheter: delayed weakness, unintentional dislodgment, leakage, catheter infection, dysesthesias, falls, LAST
Time frame: up to post operative day 4
Incidences of participants readmitted for pain control
Whether the patient was readmitted to a hospital for additional pain control.
Time frame: 3 month after surgery
Block complications
Patients will report if they experience any block complications including, neuropraxia (saphenous), transient palsies: peroneal, tibial nerve.
Time frame: up to post operative day 4
Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR.)
The survey asks for patients' view about their knee, such as how they feel about their knee and how well they are able to do usual activities. Choices on each question are: none, mild, moderate, severe, extreme
Time frame: before surgery and up to post operative day 60
Orthopedic Outcome Flexion/Knee Society Score
Patient will be asked about their range of motion (flexion ROM and Extension ROM). Data collected from surgeon's note
Time frame: 6 weeks
SF-36 questionnaire
The SF-36 measures includes the following: physical functioning (PF), role physical (RP), bodily pain (BP), general health (GH), vitality (VT), social functioning (SF), role emotional (RE), and mental health (MH). Measured on a scale of 1 to 3, with 1 = "yes limited a lot", 2 = "yes limited a little", 3 = "no not limited at all". The total score for each participant is calculated and then all the scores are average across all participants.
Time frame: up to post operative day 60
Leeds Assessment of Neuropathic Symptoms and Signs (LANSS)
The Leeds Assessment of Neuropathic Symptoms and Signs Pain Scale (LANSS) comprises of a 7-item pain scale, including the sensory descriptors and items for sensory examination. Out of the seven items in the Leeds Assessment of Neuropathic Symptoms and Signs Pain Scale (LANSS), five are symptom related and two are examination items. If patient reports surgery-related pain greater than 3 on the NRS at the 3 months and 6 months postoperative visit, patient will complete this questionnaire.
Time frame: at 3 months & 6 months
Current opioid misuse measure (COMM)
The Current Opioid Misuse Measure (COMM) is a commonly used self-report instrument to identify and monitor aberrant opioid-related behavior in chronic pain patients on opioid therapy. At the 3 months and 6 months postoperative visit, if patients are still being prescribed opioids, patient will be asked to fill out the questionnaire Choices on the questionnaire are: never, seldom, sometimes, often, very often
Time frame: at 3 months & 6 months
Incidence of patient contact via text messaging/video calls
Research staff will mark if patients contacted the pain doctor via the Diagnotes application.
Time frame: up to post operative day 4
Number of unused opioids
Patients will be asked at 1 week post-operation, about their pain medication usage (how many pills of your opioid medication do you have left?)
Time frame: up to post operative day 7
Pain catastrophizing scale (PCS)
The Pain Catastrophizing Scale (PCS) assesses the extent of catastrophic thinking due to low back pain according to 3 components: rumination, magnification, and helplessness. It is a 13-item scale, with a total range of 0 to 52. Higher scores are associated with higher amounts of pain catastrophizing.
Time frame: before the surgery and up to post operative day 60
Pain Disability Index (PDI)
The Pain Disability Index (PDI) is a widely-used instrument to measure pain-related disability. Scoring: Scores are assigned based on an 11-point scale ranging from 0 (no disability) to 10 (total disability). Scores range from 0 to 70. The higher the index the greater the person's disability due to pain.
Time frame: 3 months & 6 months
Blinding Assessment
Patient and research staff will report which group they believe the patient was randomized to.
Time frame: up to post operative day 2
Incidents of participants experiencing block complications
Data on whether patient experienced quadriceps weakness and foot drop during physical therapy. Collected from physical therapy notes.
Time frame: up to post operative day 4
Non Opioid Pain medications consumption
Research staff will document any non-opioid pain medications (lyrica, robaxin, tyelnol, etc) taken by each participant. Medications may be given at the discretion of the APS service.
Time frame: up to post operative day 60
Intravenous patient control analgesia (IV PCA) usage
Research staff will document if patient received IV PCA during their stay at the hospital. Measured in morphine equivalent. Discharge times can vary from participant to participant (from POD 0 up until POD 2)
Time frame: up to post operative day 7
Length of induction
The time it takes for the patient to be induced. Measured from induction start to induction end. Times for each participants will be calculated (in minutes) and then average across all participants.
Time frame: During the surgical procedure
Length of tourniquet use
The total time to use a tourniquet. Measured from tourniquet inflated time tourniquet deflated time. Times for each participants will be calculated (in minutes) and then average across all participants.
Time frame: During the surgical procedure
Documents are hosted by the registry — open the source record to download them.
Plan to share: No — No plan to share IPD with other researchers.
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Hospital for Special Surgery, New York