Spread of spinal anaesthesia with 0.5% bupivacaine: influence of the vertebral interspace and speed of injection.
Three millilitres of plain 0.5% bupivacaine were injected intrathecally at two different spinal interspaces (L2/3 and L4/5) and at two different speeds (15 and 30 sec) in four groups of ten patients. Injection at L2/3 over 15 sec produced a significantly higher mean maximum spread of analgesia (T6.4) when compared to injection at L4-5 over 15 sec (T10.3) (P < 0.05). Over the same interspace L2/3, injection over 15 sec also produced a higher level of spread as compared to the 30 sec group (p < 0.05). At 15 min there was a greater fall in blood pressure in the L2/3 15 sec group when compared to the other groups (p < 0.01). There was a further decrease in the blood pressure in L2/3 15 sec and L4/5 30 sec groups after 30 minutes of blockade (p < 0.01). Therefore close monitoring of cardiovascular parameters must be continued for at least 30 min in spinal anaesthesia with bupivacaine.
Chin
K W
KW
Department of Anaesthesiology, Tan Tock Seng Hospital, Singapore.
Chin
N M
NM
Chin
M K
MK
D000293:Adolescent; D000328:Adult; D000775:Anesthesia, Spinal; D001794:Blood Pressure / Q000187:drug effects; D002045:Bupivacaine / Q000008:administration & dosage*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D013131:Spine / Q000033:anatomy & histology; D013997:Time Factors
D002045:Bupivacaine