Epidural Morphine for Postoperative Analgesia After Total Knee Arthroplasty

Not Applicable

Completed

• Conditions: Total Knee Arthroplasty; Adult Patients; Femoral Nerve Block; Epidural Analgesia; Analgesic Adverse Reaction
• Interventions: Procedure: Epidural placebo; Procedure: Epidural morphine; Procedure: Single femoral nerve block; Drug: Intravenous morphine analgesia

• Registration Number: NCT03203967
• Lead Sponsor: Peking University First Hospital

Brief Summary

Single femoral nerve blockade combined with patient-controlled intravenous analgesia are used for postoperative analgesia for patients after TKA in the hospital of the investigators. Although this method provides acceptable analgesia, the incidence of opioid-associated side effects is relatively high. Low-dose epidural morphine is commonly used in postoperative analgesia after cesarean section, and the effect of single dose morphine lasts more than 20 hours, with low incidences of itching, nausea, vomiting, and respiratory depression. The investigators hypothesize that, for patients undergoing TKA, the addition of low-dose epidural morphine to single femoral nerve block and intravenous opioids can improve the postoperative analgesia, reduce the consumption of intravenous opioids and decrease opioid-associated side effects.

Detailed Description

Total knee arthroplasty (TKA) is an important therapy for patients with serious knee osteoarthritis in order to improve quality of life and relieve pain. But a large number of patients who undergo this surgery experience moderate to severe postoperative pain. Previously, the investigators used single femoral nerve blockade combined with patient-controlled intravenous analgesia for postoperative analgesia for patients after TKA. Although this method provides acceptable analgesia, the incidence of opioid-associated side effects is relatively high. Low-dose epidural morphine is commonly used in postoperative analgesia after cesarean section, and the effect of single dose morphine lasts more than 20 hours, with low incidences of itching, nausea, vomiting, and respiratory depression. The investigators hypothesize that, for patients undergoing TKA, the addition of low-dose epidural morphine to single femoral nerve block and intravenous opioids can improve the postoperative analgesia, reduce the consumption of intravenous opioids and decrease opioid-associated side effects.

Study Timeline

• Study First Submitted: 2017-05-30
• Study First Submitted QC: 2017-06-28
• Study First Posted: 2017-06-29
• Study Start: 2017-07-01
• Primary Completion: 2018-04-30
• Status Verified: 2018-05
• Study Completion: 2018-05-30
• Last Update Submitted: 2018-05-31
• Last Update Posted: 2018-06-04

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 110

Inclusion Criteria

• Adult patients (age of 18 years or older);
• American Society of Anesthesiologists classification I-III;
• Scheduled to undergo unilateral TKA under combined spinal and epidural anesthesia.

Exclusion Criteria

• Age higher than 90 years old;
• Presence of any contraindication to neuraxial block or peripheral nerve block;
• Continuous use of opioid analgesics during the last month;
• Unable to understand Numeric Rating Scale for pain evaluation or existence of language barrier;
• Severe renal insufficiency (requirement of renal replacement therapy);
• History of asthma;
• Recruited in another clinical trials.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Epidural morphine	Intravenous morphine analgesia	1. Epidural morphine (2 mg morphine in 5 ml normal saline) is administered through the epidural catheter at the end of surgery. 2. Single femoral nerve block is performed with 20 ml of 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery. 3. Intravenous morphine analgesia is provided with a patient-controlled analgesia pump which is established with 100 ml of 0.5 mg/mL morphine, programmed to deliver a 2 ml bolus with a lockout interval of 8-10 min and a background infusion of 0.5 mL/h.
Epidural placebo	Intravenous morphine analgesia	1. Epidural placebo (5 ml normal saline) is administered through the epidural catheter at the end of surgery. 2. Single femoral nerve block is performed with 20 ml of 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery. 3. Intravenous morphine analgesia is provided with a patient-controlled analgesia pump which is established with 100 ml of 0.5 mg/mL morphine, programmed to deliver a 2 ml bolus with a lockout interval of 8-10 min and a background infusion of 0.5 mL/h.
Epidural placebo	Epidural placebo	1. Epidural placebo (5 ml normal saline) is administered through the epidural catheter at the end of surgery. 2. Single femoral nerve block is performed with 20 ml of 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery. 3. Intravenous morphine analgesia is provided with a patient-controlled analgesia pump which is established with 100 ml of 0.5 mg/mL morphine, programmed to deliver a 2 ml bolus with a lockout interval of 8-10 min and a background infusion of 0.5 mL/h.
Epidural placebo	Single femoral nerve block	1. Epidural placebo (5 ml normal saline) is administered through the epidural catheter at the end of surgery. 2. Single femoral nerve block is performed with 20 ml of 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery. 3. Intravenous morphine analgesia is provided with a patient-controlled analgesia pump which is established with 100 ml of 0.5 mg/mL morphine, programmed to deliver a 2 ml bolus with a lockout interval of 8-10 min and a background infusion of 0.5 mL/h.
Epidural morphine	Epidural morphine	1. Epidural morphine (2 mg morphine in 5 ml normal saline) is administered through the epidural catheter at the end of surgery. 2. Single femoral nerve block is performed with 20 ml of 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery. 3. Intravenous morphine analgesia is provided with a patient-controlled analgesia pump which is established with 100 ml of 0.5 mg/mL morphine, programmed to deliver a 2 ml bolus with a lockout interval of 8-10 min and a background infusion of 0.5 mL/h.
Epidural morphine	Single femoral nerve block	1. Epidural morphine (2 mg morphine in 5 ml normal saline) is administered through the epidural catheter at the end of surgery. 2. Single femoral nerve block is performed with 20 ml of 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery. 3. Intravenous morphine analgesia is provided with a patient-controlled analgesia pump which is established with 100 ml of 0.5 mg/mL morphine, programmed to deliver a 2 ml bolus with a lockout interval of 8-10 min and a background infusion of 0.5 mL/h.

Primary Outcome Measures

Name	Time	Method
Percent of patients with moderate to severe pain (Numeric Rating Scale pain score of 4 or higher)	Until 48 hours after surgery.	Pain severity is evaluated with Numeric Rating Scale (NRS, an 11-point scale where 0 = no pain and 10 = the worst pain) both at rest and with movement.

Secondary Outcome Measures

Name	Time	Method
NRS pain scores (at rest and with movement) at various timepoints after surgery	At 6, 12, 24, 36 and 48 hours after surgery.	Pain severity is evaluated with Numeric Rating Scale (NRS, an 11-point scale where 0 = no pain and 10 = the worst pain) both at rest and with movement.
Recovery of motor function of the lower limb from blockade	At the end of the surgery and at 0.5, 6, 12, 24, 36, 48 hours after surgery.	Modified Bromage scale (0 = no blockade: extended limb lift off the bed; 1 = flexion/extension at knee and ankle joint; 2 = no flexion/extension at knee or ankle joint; 3 = complete blockade).
Time to begin functional exercise and ground walking	During hospital stay, up to 1 week after surgery.	Time to begin functional exercise and ground walking
Cumulative morphine consumption	Until 48 hours after surgery.	Cumulative morphine consumption during 48 hours after surgery.
Patient's satisfaction with analgesia	At 48 hours after surgery.	Evaluated in 5 scale, i.e., very satisfactory, satisfactory, neither satisfactory nor unsatisfactory, unsatisfactory, and very satisfactory.
The Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index	At 30 days after surgery.	Evaluated with the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index.
Length of stay in hospital after surgery	Until hospital discharge up to 30 days after surgery.	Length of stay in hospital after surgery
Incidence of postoperative complication	Until 30 days after surgery.	Incidence of postoperative complication within 30 days after surgery.
Quality of life (SF-12) at 30 days after surgery	At 30 days after surgery.	Evaluated with Short-Form Health Survey-12 (SF-12) at 30 days after surgery.

Trial Locations

Locations (1)

Peking University First Hospital; 🇨🇳 Beijing, Beijing, China