The effect of injection speed on the spinal block characteristics of hyperbaric bupivacaine 0.5% in the elderly.
OBJECTIVE
The purpose of this prospective, randomized, double-blind study was to compare anesthetic characteristics after two speeds of intrathecal injection of hyperbaric bupivacaine in elderly patients.


METHODS
Fifty-six patients, aged ≥65 years, undergoing transurethral surgery under spinal anesthesia were allocated randomly to two groups according to rate of intrathecal injection of 2 ml hyperbaric bupivacaine 0.5%: group Fast (maximum possible rate; mean 0.38 ml/s) n = 26; group Slow (over 40 s; 0.05 ml/s), n = 25. Spinal blocks were administered in the lateral position. Data collection at different times included sensory level, motor block, hemodynamic changes, and occurrence of neurological symptoms.


RESULTS
There was no significant difference between the groups regarding maximum sensory anesthetic level achieved (group Fast: T7 (T4-T10), median (range); group Slow T8 (T6-T10), P = 0.184); times (min) to reach (a) T10 sensory level (group Fast 5.3 ± 4.2 (mean ± SD), group Slow 8.0 ± 6.5, P = 0.093); (b) maximum sensory level (group Fast 11.6 ± 4.7; group Slow 13.6 ± 6.1, P = 0.199); and (c) 2-segment regression of anesthesia (group Fast 92.2 ± 29.6; group Slow 104.7 ± 36.1, P = 0.182). Degree and duration of motor block were similar (P = 0.947 and P = 0.895, respectively). Hemodynamic changes, ephedrine and atropine requirement, incidence of postoperative neurological symptoms after 24 h and 1 week were similar (all P > 0.05).


CONCLUSIONS
An eightfold difference in speed of intrathecal injection of 0.5% hyperbaric bupivacaine did not affect the clinical characteristics of spinal anesthesia in elderly patients undergoing transurethral surgery.
Prakash
Smita
S
Department of Anesthesia and Intensive Care, Vardhman Mahavir Medical College and Safdarjang Hospital, New Delhi 110029, India. drsunilprakash@gmail.com
Bhartiya
Veena
V
Pramanik
Vedatrayee
V
Pahilajani
Jyoti
J
Gogia
Anoop Raj
AR
Singh
Rajvir
R
D000368:Aged / Q000502:physiology*; D000775:Anesthesia, Spinal; D000779:Anesthetics, Local / Q000008:administration & dosage* / Q000009:adverse effects; D001794:Blood Pressure / Q000187:drug effects; D002045:Bupivacaine / Q000008:administration & dosage* / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007278:Injections, Spinal; D008297:Male; D016343:Monitoring, Intraoperative; D010100:Oxygen / Q000008:administration & dosage; D011446:Prospective Studies; D018401:Sample Size
D000779:Anesthetics, Local; D010100:Oxygen; D002045:Bupivacaine