Patient-Controlled Acetaminophen for Postoperative Pain

Overseen By Jinlei Li, MD, PhD

Age: 18+

Sex: Any

Trial Phase: Phase 1

Sponsor: Yale University

Must not be taking: Opioids, Benzodiazepines, Neurontin, others

Disqualifiers: Pregnancy, Chronic pain, Substance abuse, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 4 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 12 months

24 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests whether patients can effectively manage their pain medication, specifically acetaminophen, after shoulder surgery. The goal is to determine if patient-controlled medication timing is both effective and acceptable. Participants are divided into two groups: one uses a pump for liquid acetaminophen, while the other receives pills from a nurse. The trial seeks individuals who have undergone shoulder surgery and do not have chronic pain or regularly use pain medications at home. As a Phase 1 trial, the research focuses on understanding how the treatment works in people.

Do I need to stop my current medications for the trial?

The trial requires that you are not on home opioids or any other pain-modulating medications like benzodiazepines, Neurontin, or ketamine. If you are taking these, you would need to stop before participating.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that acetaminophen is a common and low-risk medication used in hospitals. It is generally safe for managing pain after surgery when administered in the right amount. Most people tolerate it well, with few serious side effects reported.

Although specific study data on using a CADD pump to deliver acetaminophen is not available, the drug itself is well-known. It is widely used and approved by the FDA for pain relief. Most people do not experience severe side effects, though some might encounter mild issues like nausea or an upset stomach.

Since this trial is in its early stages, it focuses on testing how people react to the treatment. This means limited safety data is available from the trial itself. However, the widespread use of acetaminophen suggests it is a reliable and safe option for many. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores a new way to manage postoperative pain using acetaminophen. Unlike the standard care where nurses administer acetaminophen pills, this trial allows patients to control their pain relief using a CADD pump that delivers liquid acetaminophen. This method could give patients more control over their pain management and potentially lead to faster relief since the medication is delivered directly in liquid form. By comparing these two approaches, the study aims to find out if patient-controlled administration offers better pain management and overall satisfaction.

What evidence suggests that this trial's treatments could be effective for postoperative pain?

Research has shown that patient-controlled pain relief devices, such as the CADD pump used to administer acetaminophen in one arm of this trial, often manage pain more effectively than traditional methods where a nurse administers the medication. Participants in this trial may receive acetaminophen through the CADD pump, allowing them to take the medication as needed, rather than waiting for a nurse. Studies have found that these devices can provide better pain control. Additionally, administering acetaminophen through an IV has proven effective in reducing post-surgery pain, offering significant relief in many cases. This trial will explore whether using a similar device for oral acetaminophen can offer the same benefits. Although this method of administering acetaminophen is new, it is based on proven pain management techniques. ^{3 6 7 8 9}

Who Is on the Research Team?

Jinlei Li, MD, PhD

Principal Investigator

Yale University

Are You a Good Fit for This Trial?

This trial is for individuals experiencing pain after surgery. Participants must be able to take oral medication and use a patient-controlled pump, but specific inclusion and exclusion criteria are not listed.

Inclusion Criteria

I am a nurse who will give acetaminophen to a study patient.

Exclusion Criteria

I cannot swallow pills or take liquid medication.

I cannot drink from a cup due to a neurological or movement disorder.

I have a long-term high bilirubin level due to liver condition or Gilbert's.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either patient-controlled liquid acetaminophen or nurse-administered acetaminophen pills

12 months

Study day 0, 1, 2, and 3

Follow-up

Participants are monitored for adherence to the study protocol and efficacy of the treatment

12 months

What Are the Treatments Tested in This Trial?

Interventions

• Acetaminophen

Trial Overview The study explores if patients can manage their postoperative pain by controlling their intake of liquid acetaminophen using a CADD pump versus taking regular acetaminophen tablets.

How Is the Trial Designed?

Group I: CADD pump Administered Acetaminophen (Participant Controlled) Experimental Treatment 2 Interventions

Participants will receive a CADD pump primed and programmed to deliver 650 mg liquid acetaminophen into a medication cup every 4 hours as needed (PRN).

Group II: Nurse Administered Acetaminophen Active Control 1 Intervention

Participants will receive acetaminophen pills 650 mg every 4 hours as needed (PRN) administered by nurse per standard of care

Acetaminophen is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Tylenol for:

• Pain relief
• Fever reduction

Approved in European Union as Paracetamol for:

• Pain relief
• Fever reduction

Approved in Canada as Tylenol for:

• Pain relief
• Fever reduction

Who Is Running the Clinical Trial?

Yale University

Lead Sponsor

Trials

1,963

Recruited

3,046,000+

Published Research Related to This Trial

NSAIDs are generally more effective than paracetamol for pain relief in dental surgery, while their effectiveness is similar in major and orthopedic surgeries, indicating that the choice of pain management may depend on the type of surgery.

Paracetamol is a safer alternative to NSAIDs due to its lower incidence of adverse effects, making it a preferred option for high-risk patients; combining paracetamol with NSAIDs may enhance pain relief, but more research is needed to assess potential side effects from this combination.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparative effect of paracetamol, NSAIDs or their combination in postoperative pain management: a qualitative review. Hyllested, M., Jones, S., Pedersen, JL., et al.[2022]

In a study of 50 patients undergoing endoscopic nasal surgery, parecoxib did not show superior efficacy compared to proparacetamol for postoperative pain relief, with similar pain scores and morphine consumption in both groups.

Both medications resulted in high patient satisfaction and similar side effect profiles, indicating that parecoxib is not more effective than proparacetamol for early postoperative analgesia in this surgical context.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of parecoxib and proparacetamol in endoscopic nasal surgery patients. Leykin, Y., Casati, A., Rapotec, A., et al.[2021]

Acetaminophen is a well-tolerated first-line pain reliever and fever reducer in children, commonly used in pediatric care with minimal side effects.

The introduction of intravenous acetaminophen in the U.S. provides an important alternative for pediatric patients near end-of-life who may have difficulty with oral intake or rectal administration, enhancing pain management options in palliative care.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Use of intravenous acetaminophen (paracetamol) in a pediatric patient at the end of life: case report. Marks, AD., Keefer, P., Saul, D.[2013]

In a study of 76 pediatric patients undergoing adenotonsillectomy, paracetamol alone was found to be effective and safe for managing postoperative pain, with an average pain intensity of 3.36 on a scale and a duration of pain lasting about 3 days.

Postoperative pain was notably more intense in patients who had surgery due to infectious conditions, but overall, the procedure had a low complication rate, with only 3.9% experiencing self-limited bleeding.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluation of the Efficacy of Paracetamol in the Control of Pain After Adenotonsillectomy in the Pediatric Population. Costa, R., Fernandes, Â., Fonseca, R.[2022]

In a study of 64 children undergoing (adeno)tonsillectomy, all three analgesia protocols showed significant pain levels immediately after surgery, indicating that current pain management strategies may not be sufficient.

Higher doses of paracetamol (500 mg) and the addition of codeine improved pain scores at 3 and 6 hours post-surgery compared to lower doses, suggesting that modifications in analgesic protocols could enhance pain relief after surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Prevention and control of pain in (adeno)tonsillectomy]. Boelen-van der Loo, WJ., Driessen, FG.[2020]

In a study of 60 patients recovering from knee ligamentoplasty, the use of propacetamol (an injectable form of acetaminophen) significantly reduced the need for morphine compared to a placebo, indicating its effectiveness in pain management.

The propacetamol group required fewer morphine boluses and had lower overall morphine consumption, suggesting that it can enhance analgesic efficacy when used alongside morphine in a patient-controlled analgesia setting.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The morphine-sparing effect of propacetamol in orthopedic postoperative pain. Delbos, A., Boccard, E.[2022]

In a study involving 102 pediatric patients undergoing adenotonsillectomy, both ketorolac (1 mg/kg) and propacetamol (30 mg/kg) were found to be equally effective in managing postoperative pain, regardless of whether they were administered preoperatively or postoperatively.

The study concluded that neither drug demonstrated preemptive analgesic effects within the first hour after surgery, indicating that timing of administration did not impact pain control in this context.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The preemptive analgesic effect of ketorolac and propacetamol for adenotonsillectomy in pediatric patients. Lee, IH., Sung, CY., Han, JI., et al.[2019]

In a study of 180 children undergoing adenoidectomy, oral naproxen (10 mg/kg) significantly reduced the need for rescue analgesics compared to paracetamol (20 mg/kg) and placebo, indicating its efficacy in managing post-operative pain.

The addition of pethidine (1 mg/kg) further decreased the need for rescue fentanyl by 30% and halved the number of doses required, but it also doubled the incidence of post-operative nausea and vomiting (PONV), highlighting a trade-off between pain management and side effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Oral naproxen but not oral paracetamol reduces the need for rescue analgesic after adenoidectomy in children. Korpela, R., Silvola, J., Laakso, E., et al.[2013]

In a study of 119 patients undergoing breast surgery or thyroidectomy, propacetamol provided effective postoperative pain relief, with over 90% of patients not requiring additional analgesics.

While both systematic and demand-based administration of propacetamol showed similar pain relief, the systematic group received higher doses and experienced fewer instances of pain during infusion, indicating that systematic administration may be more beneficial.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Efficacy of propacetamol in postoperative pain based on two modes of intravenous administration]. Farhat, F., Savoyen, MC., Jayr, C.[2013]

In a study of 182 patients undergoing inguinal hernia repair, a single injection of 40 mg parecoxib resulted in less intense pain at rest compared to 2 injections of 2 g propacetamol, although both treatments had similar morphine consumption and side effects.

Patients receiving parecoxib reported higher satisfaction with their pain management, with 87% rating it as good or excellent compared to 70% in the propacetamol group, indicating parecoxib may be a more effective option for postoperative pain relief.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A randomized, double-blind comparison between parecoxib sodium and propacetamol for parenteral postoperative analgesia after inguinal hernia repair in adult patients. Beaussier, M., Weickmans, H., Paugam, C., et al.[2021]

A fast-dissolving formulation of paracetamol (FD-APAP) at 1000 mg provided significantly greater pain relief and faster onset compared to both a lower dose of FD-APAP (500 mg) and standard paracetamol (650 mg) in patients after dental surgery, with the first perceptible relief occurring in just 15 minutes.

All treatments were well tolerated, indicating that FD-APAP 1000 mg is a safe and effective option for managing acute pain, particularly in postsurgical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Efficacy and speed of onset of pain relief of fast-dissolving paracetamol on postsurgical dental pain: two randomized, single-dose, double-blind, placebo-controlled clinical studies. Yue, Y., Collaku, A., Brown, J., et al.[2013]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10339749/

Effect of Educational Tools on the use of Patient-Controlled ... This study determines the effect of verbal, brochure, or video education on the use of PCA devices in patients undergoing a hysterectomy.

2. sciencedirect.com sciencedirect.com/science/article/pii/S088539240500031X

Recent Developments in Patient-Controlled Analgesia Results are often conflicting, but most investigations show a trend for better outcome when spinal application is used instead of intravenous routes, and that ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3717314/

Patient Perspectives of Patient-Controlled Analgesia (PCA) ... Patient-controlled analgesia (PCA) pumps have been shown to be more effective in treating pain than intermittent intramuscular or intravenous injections.

4. cochrane.org cochrane.org/evidence/CD007126_intravenous-paracetamol-acetaminophen-pain-after-surgery-adults-and-children

Intravenous paracetamol (acetaminophen) for pain after ... Among primary outcomes, 36% of participants receiving IV paracetamol/propacetamol experienced at least 50% pain relief over four hours compared ...

5. jscimedcentral.com jscimedcentral.com/jounal-article-info/International-Journal-of-Clinical-Anesthesiology/The-Analgesic-Efficacy-of-IV-Acetaminophen-for-Acute-Post-Operative-Pain-in-C-Section-Patients;-A-Randomized,-Double-Blind,-Placebo-Controlled-Study-8797

The Analgesic Efficacy of IV Acetaminophen for Acute Post- ... The authors concluded that IV paracetamol was an effective option for post-cesarean section analgesia and can be used to reduce opioid consumption. Total opioid ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8112920/

Patient-Controlled Analgesia (PCA) - PubMed Central - NIH Acute postoperative pain delays recovery and increases morbidity and mortality. Opioid therapy is effective but is accompanied by adverse ...

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5841478/

A Comparative Study of Oral Analgesics for Postoperative ... In addition, acetaminophen is known to be somewhat effective for postoperative pain when a sufficient dose is administered. Therefore, we considered that ...

8. rapm.bmj.com rapm.bmj.com/content/early/2025/11/03/rapm-2025-107162

Analgesic efficacy of continuous superficial parasternal ... Secondary outcomes included sternal pain within 48 hours, opioid use, quality of recovery, postoperative nausea or vomiting and chronic sternal ...

9. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6439592/

Effect of Combination of Paracetamol (Acetaminophen) and ... Although the combined use of paracetamol and ibuprofen reduced immediate postoperative morphine consumption compared with paracetamol alone in ...