Home > Journals > Minerva Anestesiologica > Past Issues > Minerva Anestesiologica 2021 July;87(7) > Minerva Anestesiologica 2021 July;87(7):766-73

CURRENT ISSUE
 

JOURNAL TOOLS

eTOC
To subscribe
Submit an article
Recommend to your librarian
 

ARTICLE TOOLS

Publication history
Reprints
Permissions
Cite this article as
Share

 

ORIGINAL ARTICLE   

Minerva Anestesiologica 2021 July;87(7):766-73

DOI: 10.23736/S0375-9393.21.15012-6

Copyright © 2021 EDIZIONI MINERVA MEDICA

language: English

Determination of the initial minimum effective dose of 0.5% bupivacaine with 20 μg of fentanyl for an operative fixation of fractured neck of femur: a prospective, observational trial

Tomas HITKA 1 , Jane O’SULLIVAN 2, Szilard SZUCS 1, Gabriella IOHOM 3, 4

1 Department of Anesthesia and Intensive Care, Cork University Hospital, Cork, Ireland; 2 Department of Anesthesia and Intensive Care, Tallaght University Hospital, Dublin, Ireland; 3 Cork University Hospital, Cork, Ireland; 4 University College of Cork, Cork, Ireland



BACKGROUND: Fractured neck of femur (FNF) is a common cause of morbidity and mortality in elderly. Spinal catheter allows fractionation of local anesthetic dose which combined with intrathecal opioid leads to a dose reduction and better hemodynamic stability. The primary objective of this paper was to investigate the initial minimum local anesthetic dose (iMLAD) of 0.5% isobaric bupivacaine with 20 μg of fentanyl administered via spinal catheter in order to commence the operative fixation of FNF.
METHODS: A prospective, single-blinded, adaptive clinical trial with patients undergoing dynamic hip screw implantation (DHS) or hemiarthroplasty (HEMI) due to FNF. The Dixon and Massey’s up and down method was used to determine the ED50 of intrathecal bupivacaine. This figure was confirmed with Probit analysis, in addition to the ED95.
RESULTS: Using the Dixon and Massey’s approach, the iMLADED50 for DHS was 0.29 mL (1.45 mg) and the iMLADED50 for HEMI was 0.33 mL (1.65 mg) of 0.5% isobaric bupivacaine. The Probit analyses demonstrated that the iMLADED95 for DHS and HEMI were 0.32 mL (1.6 mg) and 0.34 mL (1.7 mg) respectively. The mean cumulative dose of 0.5% bupivacaine for the whole surgery was 0.67 mL (3.35 mg) and 0.87 mL (4.35 mg) in the DHS and HEMI groups, respectively.
CONCLUSIONS: This study demonstrates that the placement of a spinal catheter allows for careful titration of local anesthetic, enabling a reduction of the initial intrathecal dose of 0.5% isobaric bupivacaine below 0.4 mL (2 mg) and leading to a significant reduction of a dose required for the whole surgery when combined with an intrathecal opioid.


KEY WORDS: Anesthesia; Femoral neck fractures; Fracture fixation

top of page