Comparison Between Blocks or Not in Joint Arthroplasty (BLAST)

April 27, 2026 updated by: Region Skane

Postoperative Analgesia in Patients Undergoing Hip and Knee Replacement Surgery - a Study Comparing Ultrasound-guided Nerve Blocks With Intraoperative Local Anesthetic Infiltration or Opioids

The purpose of this study is to evaluate the effect on postoperative pain, opioid consumption and function by adding a combination of regional blocks with local anaesthetic before total hip- and knee arthroplasty compared to standard pain management strategies.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

400 patients with osteoarthritis of the knee (200) or hip (200) necessitating total hip- or knee replacement are entered into the study. All patients are given a standard protocol of analgesics pre- and postoperatively. Patients are receiving general- or spinal anaesthesia during the surgery. General anaesthesia is conducted using Remifentanil 50ug/ml and Propofol 20 mg/ml utilizing a TCI protocol. The airway is managed by LMA or endotracheal tube. Spinal anaesthesia is conducted using isobaric Bupivacaine (hip) and hyperbaric bupivacaine (knee). Decision regarding type of anaesthesia is following guidelines of our department taking contraindications and patients preference into account.

Patients randomized to the block-group undergoing hip replacement surgery with posterior approach are given och combination of PENG block and Iliohypogastric block using Ropivacain 5 mg/ml with a total dose of 200 mg along with clonidine in a total dose of 75 micrograms. Patients undergoing hip replacement with lateral approach are given a combination of PENG block and LFCN block using Ropivacain 5 mg/ml with a total dose of 125 mg along with clonidine in a total dose of 56,25 micrograms. Patients randomized to the standard pain management strategy undergoing hip replacement surgery are given a combination of opioids, paracetamol and Cox-II inhibitors.

Patients randomized to the block-group undergoing knee replacement surgery are given a combination of iPACK-, genicular-, AFCN-, adductor canal and vastus intermedius block using Ropivacain 5 mg/ml with a total dose of 225 mg along with clonidine in a total dose of 75 micrograms. Patients randomized to the standard pain management strategy undergoing knee replacement surgery are given a perioperative periarticular LIA using Ropivacaine 300 mg along with 0,5 mg of adrenaline.

The randomization is executed on the day before surgery by opening of a closed numbered envelope giving information if the specific patient should have a block (intervention) or not (control). There are 200 prepared envelopes for the hip replacements and 200 for the knee replacements, with 100 blocks and 100 no blocks for each type. The envelopes are prepared by block randomization performed by computer software. Nurses and physiotherapists who evaluate postoperative pain are blinded from the intervention. The physician compiling the data from the study is also blinded to the intervention.

Preoperatively, information is collected regarding doses of analgesics and pain in everyday life is evaluated using the NRS scale. Preoperative pain is evaluated at rest and during mobilization.

Postoperatively, an evaluation of pain is made. After the operation the patients are monitored at the ward by the nurses and physiotherapists. The registration takes place using the subjective Numeric Rating Scale (NRS) and the objective Critical-Care Pain Observation Tool (CPOT). Pain is continuously evaluated during the hospital stay. The final registration takes place at the return visit 14 days after surgery. During the hospital stay, other parameters such as opioid consumption, requirement for urinary catheter, postoperative nausea and vomiting (PONV), time to mobilization and neurological complications are also registered. The number of extra opioid doses the patient requires are also registered. The number of days the patients need to stay in hospital after surgery are registered.

Study Type

Interventional

Enrollment (Estimated)

400

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Sweden
      • Trelleborg, Sweden
        • Dept of Anaesthesiology, Trelleborg Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Osteoarthritis of the knee- or hip necessitating total knee- or hip replacement
  • Patients who understand the conditions of the study and are willing to participate for the length of the prescribed follow-up

Exclusion Criteria:

  • Known allergy to local anesthetics or other contraindication for the use of local anesthetics.
  • Coagulopathy
  • Bilateral operation
  • Revision arthroplasty

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Block

Hip Arthroplasty: Multimodal analgesic therapy + Ultrasound guided PENG block and Iliohypogastric block or LFCN-block.

Knee arthroplasty: Multimodal analgesic therapy + Ultrasound guided iPACK block, triple Genicular blocks, Vastus intermedius block, Adductor canal block and AFCN-block.
Drug: Ropivacain 5 mg/ml + Clonidine
Drug used in the block
No Intervention: No block

Hip Arthroplasty: Multimodal analgesic therapy

Knee Arthroplasty: Multimodal analgesic therapy + LIA

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Difference in Postoperative pain assessed by NRS
Time Frame: The day of surgery, postop day 1 and 14 days post-surgery
Patient experienced postop pain assessed by NRS (0-10)
The day of surgery, postop day 1 and 14 days post-surgery

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Difference in analgesia consumption
Time Frame: The day of surgery, postop day 1 and 14 days post-surgery
Difference in extra oral- and intravenous analgesia consumption (tablets or injections - in mg)
The day of surgery, postop day 1 and 14 days post-surgery
Time to mobilization
Time Frame: The day of surgery, postop day 1
Difference in time mobilizing to standing after surgery
The day of surgery, postop day 1
Incidence of postoperative nausea and vomiting
Time Frame: The day of surgery, postop day 1
Difference in postoperative nausea and vomiting (reported frequency)
The day of surgery, postop day 1
Difference in postoperative pain depending on method of anesthesia
Time Frame: The day of surgery, postop day 1 and 14 days post-surgery
Difference in postoperative pain depending on method of anesthesia, i.e. General- or Spinal anesthesia. Assessed by NRS (0-10)
The day of surgery, postop day 1 and 14 days post-surgery
urine catheter usage
Time Frame: 1-5 days post-surgery
Difference in frequency of urine catheter usage
1-5 days post-surgery
neurological complications
Time Frame: The day of surgery, postop day 1 and 14 days post-surgery
Difference in frequency of neurological complications (reported to and assessed by physiotherapist)
The day of surgery, postop day 1 and 14 days post-surgery
Days in hospital
Time Frame: 1-5 days post-surgery
Number of postoperative days in hospital
1-5 days post-surgery
opioid consumption 14 days
Time Frame: 14 days post-surgery
Difference in opioid consumption 14 days after surgery
14 days post-surgery

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Region Skane

Investigators

  • Principal Investigator: Gunnar Flivik, MD PhD, Department of Orthopedics, Skane Univ Hosp

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 1, 2024

Primary Completion (Actual)

March 30, 2025

Study Completion (Estimated)

April 26, 2026

Study Registration Dates

First Submitted

January 4, 2024

First Submitted That Met QC Criteria

January 18, 2024

First Posted (Actual)

January 30, 2024

Study Record Updates

Last Update Posted (Actual)

April 28, 2026

Last Update Submitted That Met QC Criteria

April 27, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • BLAST study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

General unidentified data and study protocol are available on request

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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