Effects of a continuous adductor canal block (ACB) added to local infiltration anesthesia (LIA) on pain and ambulation after total knee arthroplasty (TKA)

• Register: ISRCTN
• Last refreshed on: 30 October 2017
• Main ID: ISRCTN68176033
• Date of registration: 27/10/2016
• Prospective Registration: No
• Primary sponsor: Akureyri Hospital
• Public title: Effects of a continuous adductor canal block (ACB) added to local infiltration anesthesia (LIA) on pain and ambulation after total knee arthroplasty (TKA)
• Scientific title: A randomised, double-blind, placebo-controlled trial with 69 patients on the effects of a continuous adductor canal block (ACB) added to local infiltration anesthesia (LIA) on pain and ambulation after total knee arthroplasty (TKA)
• Date of first enrolment: 01/10/2015
• Target sample size: 69
• Recruitment status: Completed
• URL: http://isrctn.com/ISRCTN68176033
• Study type: Interventional
• Study design: Single-centre double-blind randomised placebo controlled trial (Treatment)

Countries of recruitment

Iceland

Contacts

• Name: Svava Gudmundsdottir

Key inclusion & exclusion criteria

Inclusion criteria: 1. Patients scheduled for primary unilateral cemented TKA under spinal anesthesia
2. Aged 50 – 90 years
3. With American Society of Anesthesiologists (ASA) physical status I-III
Exclusion criteria: 1. Daily intake of opioids (20 mg/day of oral morphine equivalent for > 12 weeks)
2. Inability to cooperate
3. Peripheral neuropathy
4. Allergy to any of the study medications
5. Renal insufficiency (creatinine levels > 100 µmol/L and > 110 µmol/L for women and men respectively)

Age minimum:
Age maximum:
Gender: Both

Health Condition(s) or Problem(s) studied

Pain management after total knee arthroplasty
Signs and Symptoms
Pain management after total knee athroplasty

Intervention(s)

All eligible patients are sent a letter with information about the study. At the preoperative assessment the patients sign the written consent if they wish to participate and at the same time demographic and preoperative data will be collected (age, height, weight, BMI, gender, race, pain medication use and ASA-score). Participants are then randomised to one of two groups using a computer-generated randomization list (Research randomizer, www.randomizer.org) in a 1:1 ratio with 20 numbers in each block. Every participant is assigned a consecutive study-number from 1-69 and receives the treatment assigned according to the randomization list.

Intervention group: Participants receive 0.2% ropivacaine
Placebo group: Participants receive normal saline

Both groups (intervention and placebo) are given the study medication continuously through a catheter in the adductor canal at 6 ml/h for 48 hours after the total knee arthroplasty surgery.

Participants in both groups are followed up on postoperative days one and two at which time physiotherapists assess their pain and mobility levels. Participants also have their medical records reviewed upon discharge to record any adverse events and the length of their hospital stay.

Primary Outcome(s)

Peak pain levels in the operated knee during morning physiotherapy session are measured using a Numeric Rating Scale (NRS) on postoperative day 1 and postoperative day 2.

Secondary Outcome(s)

1. Pain at rest was assessed using a numerical rating scale (NRS) before the morning physiotherapy session on postoperative day 1 and 2
2. Total pain medication used by the patient from the time of admission until 48 hours after the surgery is registered and calculated into oral morphine equivalent by reviewing the patients’ medical files from the medication database “Therapy” used by Akureyri Hospital to register patient’s medications 48 hours after admission
3. Total use of antiemetics (metoclopramide, ondansetron, haloperidol and dexamethasone) is gathered by reviewing the patient’s medical files from the medication database from the drug database “Therapy” used by Akureyri Hospital to register patient’s medications 48 hours after admission
4. Mobility is assessed using the Timed Up and Go (TUG) test on the morning of postoperative day 2
5. Actual length of hospital stay is recorded by reviewing patient’s medical files right after discharge
6. Time from the end of surgery until additional pain medication is given is gathered from the medication database “Therapy” used by Akureyri Hospital to register patient’s medications at the time of discharge
7. Time taken for patient to meet ready for discharge criteria following knee replacement surgery (able to walk with crutches, use only oral analgesia, bend the operated knee =70°, climb stairs and had no acute medical problems present) is measured by reviewing medical records at the time of discharge
8. Quadriceps muscle strength is assessed by the ability of the patient to hold the affected limb up with the knee extended against resistance of the examiner (using manual muscle testing (MMT) with 0= no contraction, 1= flicker of contraction, 2= active movement with gravity eliminated, 3= active movement against gravity but not resistance, 4= active movement against gravity and some resistance and 5= normal strength) in the morning of postoperative day 1 and 2
9. Nausea is assessed on a 5-point scale (0= no nausea, 1= mild, 2= moderate, 3= severe, and 4= vomiting episode) in the morning of postoperative day 1 and 2
10. Goals of ambulation are measured by using the 10-point mobility scale by the physiotherapists in the morning physiotherapy session of postoperative day 1 and 2
11. Straight leg raise is assessed by asking the patient to hold his lower limb 10 cm from the bed with fully extended knee for 10 seconds in the morning of postoperative day 1 and 2
12. Flexion of the knee is assessed using a clinometer in the morning of postoperative day 1 and 2.
13. Falls of patients are recorded by reviewing the patients’ medical files after discharge
14. Toxic effects of the ropivacaine (nausea, vomiting, hypotension and bradycardia) are observed by the nurses of the ward while the participants had the adductor canal catheter every morning and during routine follow up by the nurses and through measuring vitals every 4-6 hours during the entire hospital stay
15. Drainage of blood in the drainage is measured (in ml) when the drainage was removed in the morning of postoperative day 1
16. Blood transfusion rate is recorded in the patient medical files by the time the patient was discharged

Secondary ID(s)

3/2015

Source(s) of Monetary Support

Science fund of Akureyri Hospital (Vísindasjóður Sjúkrahússins á Akureyri), Science fund of the physicians council of Akureyri Hospital (Vísindasjóður Læknaráðs, Sjúkrahússins á Akureyri)