Anaesthesia for Hip and Knee Arthroplasty (SPIGA)

Effective and safe anaesthesia is fundamental to perioperative care. Hip and knee arthroplasty are among the most frequently performed surgical procedures worldwide and are typically performed under either spinal or general anaesthesia. However, high-quality comparative evidence regarding the benefits and harms of these anaesthetic techniques remains limited and inconclusive.

Both techniques are associated with short- and long-term risks, including postoperative nausea and vomiting, hypotension, nerve injury, acute kidney injury, and respiratory and cardiovascular complications. In addition, they may differentially modulate the surgical stress response, potentially influencing postoperative recovery and risk of complications.

Objective:

To compare the benefits and harms of spinal versus general anaesthesia in patients undergoing hip or knee replacement. We hypothesise that spinal anaesthesia results in better postoperative outcomes than general anaesthesia.

Intervention:

Patients undergoing elective primary hip or knee arthroplasty will be randomised to receive either spinal or general anaesthesia, with randomisation stratified by participating centre.

Design:

The SPIGA trial is an investigator-initiated, multicentre, randomised, superiority clinical trial. Participants will be randomly allocated at a 1:1 ratio using a central, computer-generated randomisation sequence. A total sample size of 3000 participants was determined using simulation-based methods to provide at least 90% power to detect a prespecified minimally clinically important difference, corresponding to an increase of one hospital-free day in at least 10% of participants at a two-sided significance level of 0.05.

Planned sub-studies

• Short-term perioperative outcomes (0-24h postoperatively)
• Stratified analysis of anaesthetic regimens
• Impact of preoperative clinical frailty

Inclusion criteria

• Scheduled for elective primary elective hip or knee arthroplasty, including unicompartmental knee

Exclusion criteria

• Scheduled for elective primary hip or knee arthroplasty, including unicompartmental knee
• Age ≥ 18 years
• Unable to communicate in written and/or spoken Danish Contraindications against either spinal or general anaesthesia