From the Guidelines
Prophylactic lumbar drain placement before open thoracoabdominal aortic aneurysm (TAAA) repair is recommended to reduce the risk of spinal cord ischemia and paraplegia, as supported by the most recent guidelines from 2022 1. The most current data supports placement of a lumbar drain before surgery with cerebrospinal fluid (CSF) drainage to maintain CSF pressure below 10-12 mmHg during and after surgery.
- The drain should be placed preoperatively and maintained for 48-72 hours postoperatively, with drainage rates typically set at 10-15 mL/hour as needed to maintain target pressure.
- Drainage should be temporarily stopped if CSF pressure falls below 8 mmHg to prevent overdrainage complications.
- The drain should be clamped for 4-6 hours before removal to ensure neurological stability. This approach has been shown to reduce paraplegia rates from approximately 13% to 5% in high-risk TAAA repairs, as noted in previous studies 1. The protective mechanism involves reducing CSF pressure to improve spinal cord perfusion pressure during periods of aortic cross-clamping when blood supply to the spinal cord is compromised. Additional protective measures should include:
- Maintaining mean arterial pressure between 80-100 mmHg
- Moderate hypothermia during surgery
- Vigilant neurological monitoring postoperatively to detect any early signs of spinal cord ischemia that would warrant immediate intervention, as highlighted in the 2022 guidelines 1 and previous studies 1.
From the Research
Lumbar Drain Prophylaxis in Open Thoracoabdominal Aneurysm Repair
- The use of lumbar drains in preventing spinal cord injury following thoracoabdominal aortic aneurysm repair has been studied extensively 2.
- A systematic review and meta-analysis found that cerebrospinal fluid drainage (CSFD) decreased spinal cord injury by nearly half (relative risk 0.42,95% confidence interval 0.25-0.70; p = 0.0009) in the pooled analysis 2.
- Another study found that CSFD reduced the risk of spinal cord injury from a maximum of 20% to a minimum of 2.3% 3.
- However, lumbar drain placement is associated with potential complications, including nonfunctionality, catheter dislodgment or fracture, CSF leak, and postdural puncture headache 4.
- The major complications of CSFD include spinal and cranial epidural/subdural hematomas, VI nerve palsies, retained catheters, meningitis/infection, and spinal headaches 3.
- A study found that subdural hematoma is an unusual and potentially catastrophic complication after thoracoabdominal aortic aneurysm repair, and prompt recognition and neurosurgical intervention is necessary for survival and recovery 5.
- The use of lumbar cerebrospinal fluid drainage in thoracoabdominal aortic aneurysm repairs has been described, and improved outcomes have been seen with the use of methods to reduce cerebrospinal fluid pressure 6.
Complications and Risks
- The most common complication of lumbar drain placement is nonfunctionality, occurring in 16% of patients 4.
- Other complications include catheter dislodgment or fracture, CSF leak, and postdural puncture headache, which occur in 4%, 7%, and 4% of patients, respectively 4.
- The risk of spinal cord injury due to decreased cord perfusion following thoracic/thoracoabdominal aneurysm surgery ranges up to 20% 3.
- The use of CSFD has been shown to reduce the incidence of permanent spinal cord injury from up to 10-20% down to 2.3-10% 3.
Best Practices
- Lumbar drain placement should be guided by a set protocol and used whenever the aortic stent graft coverage is planned to extend more proximal than 40 mm above the celiac artery 4.
- The majority of lumbar drains should be left in place for ≤48 hours, with 21% removed during the first 24 hours and 61% removed between 24 and 48 hours 4.
- Care should be taken to prevent complications related to overdrainage, and higher lumbar drain popoff pressures may be necessary together with meticulous monitoring of patient position and neurologic status 5.