From the Guidelines
If your tourniquet has been up for 90 minutes during a knee replacement surgery and you're not finished, you should consider releasing the tourniquet while maintaining hemostasis to complete the procedure. The maximum safe tourniquet time is generally considered to be 1-2 hours, with 90 minutes being a common threshold where risks increase significantly, as suggested by studies on tourniquet use in trauma settings 1. To proceed, deflate the tourniquet, identify and control any bleeding vessels with electrocautery or ligation, and continue the surgery. You may need to use suction more aggressively and additional lap sponges to maintain visualization. Some key points to consider in managing the tourniquet include:
- Allowing at least 10-15 minutes of reperfusion before reapplication if the tourniquet needs to be reapplied 1.
- Administering appropriate pain medication during the reperfusion period, as the patient may experience reperfusion pain.
- Balancing surgical needs against potential tissue damage, taking into account patient factors like peripheral vascular disease or coagulopathy. Prolonged tourniquet time increases risks of nerve injury, muscle damage, compartment syndrome, and systemic effects like metabolic acidosis from reperfusion, highlighting the importance of careful management and consideration of the latest guidelines on tourniquet use 1.
From the Research
Tourniquet Use in Knee Replacement Surgery
- The use of a tourniquet in knee replacement surgery has been a topic of debate, with both benefits and drawbacks associated with its use 2.
- Benefits of tourniquet use include improved visualization, decreased blood loss, shorter operative times, and improved antibiotic delivery 2.
- However, tourniquet use has also been associated with postoperative pain, neuromuscular injuries, wound complications, reperfusion injury, increased risk of thrombosis, patellar tracking issues, delayed rehabilitation, and negative effects on patients with vascular disease 2, 3.
Risks Associated with Prolonged Tourniquet Use
- Prolonged tourniquet use, such as in cases where the surgery exceeds 90 minutes, may increase the risk of ischemia-reperfusion injury and oxidative stress 4, 5.
- Ischemia-reperfusion injury can lead to the release of oxygen free radicals and inflammatory cytokines, contributing to local and remote organ damage 5.
- The risk of serious adverse events, including venous thromboembolism, infection, re-operation, and mortality, may also be higher with prolonged tourniquet use 6.
Management of Prolonged Tourniquet Use
- In cases where the tourniquet has been in place for an extended period, such as 90 minutes, it is essential to carefully monitor the patient's condition and be prepared to address any potential complications 6.
- The use of interventions such as propofol, ischemic pre-conditioning, and antioxidants may help reduce the risk of oxidative stress and ischemia-reperfusion injury 4, 5.
- However, the effectiveness of these interventions in reducing the risk of complications associated with prolonged tourniquet use is still being researched, and more studies are needed to provide clear guidelines 4, 3, 5.