Vws. Chan et al., The impact of saline flush of the epidural catheter on resolution of epidural anesthesia in volunteers: A dose-response study, ANESTH ANAL, 89(4), 1999, pp. 1006-1010
Citations number
7
Categorie Soggetti
Aneshtesia & Intensive Care","Medical Research Diagnosis & Treatment
We evaluated the effect of 1, 20, and 40 mL of epidural saline flush on rec
overy from lidocaine epidural anesthesia. Eight volunteers were studied for
three study periods, each separated by 72 h. The volume of saline was rand
omized, and a new catheter was inserted for each study period. A standardiz
ed dose of 20 mL of 2% plain lidocaine was injected for 10 min, followed by
an epidural saline flush 30 min later. Sensory block was assessed by pinpr
ick and transcutaneous electrical stimulation and motor block by a modified
Bromage scale and isometric maximal force contraction. Times to void and a
mbulate independently before discharge were recorded. Peak plasma lidocaine
concentrations and time to peak concentration wore determined. Results fro
m six volunteers showed that epidural saline, 40 mL, significantly altered
anesthetic resolution, accelerating the time of complete sensory and motor
block regression (P < 0.05). Median peak levels of sensory and motor block
and times to void and ambulate were similar among treatment groups. Peak pl
asma lidocaine concentrations were similar in all treatment groups. Our dat
a suggest that a 40-mL epidural saline injection 30 min after the induction
facilitates regression of epidural lidocaine anesthesia, but a 20-mL bolus
does not. Epidural saline injection does not affect vascular absorption of
epidural lidocaine. Implications: Epidural catheter flushing with 40 mL of
saline, after establishment of epidural lidocaine anesthesia, can facilita
te sensory and motor block recovery. However, this does not affect vascular
absorption of epidural lidocaine.