Epidural Morphine for Postoperative Analgesia After Total Knee Arthroplasty
Condition: Adult Patients; Total Knee Arthroplasty; Epidural Analgesia; Femoral Nerve Block; Analgesic Adverse Reaction
MeSH terms: Agnosia
Study type: Interventional

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.
    

Intervention name(s): Epidural morphine; Epidural placebo; Single femoral nerve block; Intravenous morphine analgesia
Intervention type(s): Procedure; Procedure; Procedure; Drug
Intervention description(s): 2 mg of morphine (0.4 mg/ml morphine in 5 ml normal saline) is administered through the epidural catheter at the end of surgery.; 5 ml normal saline is administered through the epidural catheter at the end of surgery.; Single femoral nerve block is performed with 20 ml 0.5% ropivacaine under the guidance of ultrasonography and nerve stimulator after surgery.; 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.
Intervention MeSH terms: Morphine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Adults; Unilateral TKA; Single femoral nerve block; Low-dose epidural morphine; Effect of postoperative analgesia; Quality of life