Korean J Anesthesiol.  2018 Apr;71(2):141-148. 10.4097/kjae.2018.71.2.141.

Effects of bilateral superficial cervical plexus block on sevoflurane consumption during thyroid surgery under entropy-guided general anesthesia: a prospective randomized study

• Kannan S
• Surhonne N
• R CK
• B K
• D DR
• R S RR

• KMID: 2411222
• DOI: http://doi.org/10.4097/kjae.2018.71.2.141

Abstract

BACKGROUND
Bilateral superficial cervical plexus block (BSCPB) provides good postoperative analgesia, but its effect on anesthetic consumption is unknown. This study evaluated the effects of BSCPB on sevoflurane consumption during thyroid surgery.
METHODS
Fifty patients were randomly allocated into groups A and B of 25 each in this prospective double-blind study. Group A received BSCPB with 20 ml 0.25% bupivacaine, whereas group B received 20 ml saline immediately before entropy-guided general anesthesia. Intraoperative hemodynamic parameters, end-tidal sevoflurane concentration, minimum alveolar concentration, and sevoflurane consumption were recorded. Postoperative pain was assessed using a visual analog scale, and the time of the first request for analgesia was noted. All side effects were recorded.
RESULTS
Demographics were comparable. Mean sevoflurane consumption [for 30 min: group A = 7.2 (1.1) ml, group B = 8.8 (2.0) ml, P = 0.001; for 60 min: group A = 13.5 (1.7) ml, group B = 16.5 (3.9) ml, P = 0.002] and mean end-tidal sevoflurane concentration [for 30 min: group A = 1.2% (0.2%), group B = 1.4% (0.2%), P = 0.008; for 60 min: group A = 1.2% (0.1%), group B = 1.4% (0.2%), P = 0.010] were significantly lower in group A. Patients in group A had a longer duration of analgesia [361.6 (79.5) min vs. 151.0 (60.2) min, P < 0.001] compared to those in group B.
CONCLUSIONS
Preinduction BSCPB during thyroid surgery significantly reduced sevoflurane consumption and increased the duration of postoperative analgesia.

Keyword

Analgesia; Cervical plexus; Entropy; Nerve block; Sevoflurane; Thyroidectomy

MeSH Terms

Analgesia
Anesthesia, General*
Bupivacaine
Cervical Plexus Block*
Cervical Plexus*
Demography
Double-Blind Method
Entropy
Hemodynamics
Humans
Nerve Block
Pain, Postoperative
Prospective Studies*
Thyroid Gland*
Thyroidectomy
Visual Analog Scale
Bupivacaine