Perineural injection to nerve root and radicular blood flow: a clinical study during spinal surgery.
OBJECTIVE
To investigate the effects of the perineural injection of lidocaine or corticosteroids on radicular blood flow during spinal surgery.


METHODS
After lumbar discectomy, a probe for laser Doppler flowmetry was placed directly on the 4th or 5th lumbar nerve root. Thirty patients undergoing lumbar discectomy were randomly assigned to one of three groups. Each group received one of three protocols for a perineural injection to the nerve root: 1.0 mL 0.9% saline in group A, 1.0 mL 1% lidocaine in group B or 1.0 mL dexamethasone (4 mg) in group C. Measurements included radicular blood flow, mean arterial pressure, haemoglobin concentration, percutaneous oxygen saturation and end-tidal carbon dioxide tension. Radicular blood flow was measured by laser Doppler flowmetry before the injection and 15 min after these injections. The three groups were similar with respect to mean arterial pressure, haemoglobin concentration, percutaneous oxygen saturation and end-tidal carbon dioxide tension.


RESULTS
Radicular blood flow did not change after the injection in any of the groups.


CONCLUSIONS
The results suggest that the perineural injection of 1% lidocaine or dexamethasone does not affect radicular blood flow during lumbar discectomy.
Department of Anaesthesia, Nagasaki Rosai Hospital, 2-12-5, Setogoshi, Sasebo, Japan.
M
M
Fukusaki
M
M
Miyako
T
T
Nakamura
H
H
Miyoshi
K
K
Sumikawa
H
H
Konishi
S
S
Hara
D000305:Adrenal Cortex Hormones; D000328:Adult; D000775:Anesthesia, Spinal; D000779:Anesthetics, Local; D017586:Diskectomy; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007267:Injections; D017078:Laser-Doppler Flowmetry; D008012:Lidocaine; D008297:Male; D008875:Middle Aged; D011229:Preanesthetic Medication; D012039:Regional Blood Flow / Q000187:drug effects; D013116:Spinal Cord / Q000098:blood supply / Q000601:surgery*; D013126:Spinal Nerve Roots / Q000098:blood supply*
D000305:Adrenal Cortex Hormones; D000779:Anesthetics, Local; D008012:Lidocaine