Background: There is a debate about the dose of hyperbaric bupivacine for
spinal anesthesia for cesarean delivery in obese parturients. While it is concessive that the dose of spinal bupivacine is reduced in pregnant compared with
non-pregnant parturient due to many factors. But it is still controversial
whether local anesthetic should further reduce in obese patients or not. In
this perspective, observation study, we tested the influence of BMI on vasopressor requirements and block height. Methods: Three groups of 40 parturients, group A (Body mass index (BMI) < 30 kg/m2
), group B (BMI 30 - 45
Kg/m2
) and group C (BMI > 45 kg/m2
) requiring elective cesarean section
were recruited all patients received 12.5 mg subarachnoid hyperbaric bupivacine combined with 20 ug fentanyl. Dermatomal levels were assessed after
subarachnoid injection using touch sensation at 2 minutes interval for first 10
minutes then every 5 minutes. Vasopressor requirements in the first 45 minutes after subarachnoid injection, and maximum block heights using touch
sensation were assessed as primary outcomes. Secondary outcomes were extent
of motor block (peak flow rate), technique difficulty (number of attempts),
maternal side effects and neonatal outcomes. Results: There was no significant difference in mean blood pressure (MBP) between group A and B but
the difference was significant in group C in relation to other two groups, mean
number of hypotensive episodes was significantly higher in group C than
group A, B with no significant difference in incidence between group A and B
(P < 0.001) (3.28 vs 3.98 vs 5.98). Total dose of vasoprenor and total volume
of fluid infused were higher in group C than group A, B. In group A the maximum block level extended above T3 in 5 patients (12.5%), with predominance
of T5 (35%), in group B the maximum level extended above T3 in 10 patients
How to cite this paper: Elmeliegy, M. (2020)
Effect of Body Mass Index on Anesthesia
Characteristics and Vasopressor Requirements during Spinal Anesthesia for Elective
Cesarean Section. Open Journal of Anesthesiology, 10, 157-169.
https://doi.org/10.4236/ojanes.2020.104014
Received: December 22, 2019
Accepted: April 27, 2020
Published: April 30, 2020
Copyright © 2020 by author(s) and
Scientific Research Publishing Inc.
This work is licensed under the Creative
Commons Attribution International
License (CC BY 4.0).
http://creativecommons.org/licenses/by/4.0/
Open Access
DOI: 10.4236/ojanes.2020.104014 Apr. 30, 2020 157 Open Journal of Anesthesiology
M. Elmeliegy
(25%) with predominance of T4 (45%) and in group C the maximum block
level extended above T3 in 21 patients (52.5%) with predominance of T3
(32.5%). Significant decrease in the mean of peak expiratory flow rate (PEFR)
in group C than group A, B, 30 minutes after subarachnoid injection of bupivacine (P = 0.004) (343.75 ± 35.06 vs 335.36 ± 32.96 vs 320.38 ± 24.0 ml). No
cases required analgesic supplementation. Conclusion: Sensory testing using
touch modality to detect extent of anesthesia, showed at 25 minutes after spinal
anesthesia induction, significantly higher level in group C than the other two
groups. Vasopressor requirements during the first 45 minutes of spinal anesthesia were not different between group A, B but significantly higher in group
C. Time for regression of anesthesia was longer in group C, which may be
helpful regarding longer surgical time. Single shots spinal anesthesia of 12.5
mg hyperbaric bupivacine produce clinically equivalent effect in parturients
with BMI < 45 Kg/m2 with no need for dose reduction but caution and dose
adjustment recommended in parturients with BMI > 45 Kg/m2
. |
