Anesthesia for hip surgery can be performed with ultrasound guided blockade of the mesh of nerves (the lumbar plexus) supplying the hip region from the lumbar spinal nerves. This is a relevant technique in patients with severe cardiac comorbidity. The technique is a safer alternative compared to general or spinal anesthesia in these fragile patients. The most recognized technique with ultrasound guidance (Karmakars technique) is technically demanding and based on injection of local anesthetic relatively close to the exit of the spinal nerves from the spine. The risk is spread of local anesthetic to the spinal canal prompting a risk of low blood pressure. This may be fatal in high risk patients. The investigators have developed a simple technique based on injection away from the spinal canal. The investigators expect minimal risk of spread of local anesthetic to the spinal canal with this technique. This randomized, double blinded trial compares the new technique to the established technique of ultrasound guided blockade of the lumbar plexus. The hypothesis is that the new technique has a higher success rate with reduced effect on blood pressure for ultrasound guided lumbar plexus block compared to the established technique.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
DOUBLE
Enrollment
20
Lumbar plexus block guided by ultrasound and nerve stimulation with the patient in the lateral position and the probe in the parasagittal plane inserting the block needle between the transverse processes of L3 and L4 until an appropriate neuromuscular response is produced.
Lumbar plexus block guided by ultrasound and loss of resistance (LOR) with the patient in the lateral position and the probe in the parasagittal plane inserting the block needle between the transverse process of L5 and the sacral bone until an appropriate LOR is produced.
Department of Anesthesiology, Aarhus University Hospital
Aarhus, Denmark
Success of complete sensory blockade of dermatomes L2, L3, L4, L5, S1
Time frame: 30 minutes after injection of local anesthetic
Plasma lidocaine level (mcg/mL)
Chromatography analysis
Time frame: 0, 5, 10, 20, 40, 60, and 90 minutes after injection of local anesthetic
Block performance time
Time frame: From start of probe on the skin until injection of local anesthetic is completed
Patient satisfaction
Time frame: Immediately after completion of injection of local anesthetic
Mean arterial blood pressure (MAP)
Absolute measure and relative change from pre-block measure
Time frame: 5 minutes after completion of injection of local anesthetic
Cost-effectiveness
Estimated as incremental cost-effectiveness ratio
Time frame: Block performance time period
Sensory blockade of each dermatome L1, L2, L3, L4, L5, S1, S2, and S3 (cold, warmth, touch, pain)
Time frame: 30 minutes after completed injection of local anesthetic
Sensory blockade of the femoral nerve (cold, warmth, touch, pain)
Time frame: 30 minutes after completion of injection of local anesthetic
Motor blockade of the femoral nerve
Time frame: 40 minutes after completion of injection of the local anesthetic
Motor blockade of the obturator nerve
Time frame: 40 minutes after completion of injection of the local anesthetic
Perineural spread of local anesthetic (with contrast) estimated with MRI
Time frame: 60 minutes after completion of injection of local anesthetic
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.