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. 2016 Apr;69(2):143-8.
doi: 10.4097/kjae.2016.69.2.143. Epub 2016 Mar 30.

Comparison of spinal anesthesia dosage based on height and weight versus height alone in patients undergoing elective cesarean section

Affiliations

Comparison of spinal anesthesia dosage based on height and weight versus height alone in patients undergoing elective cesarean section

Khalid Maudood Siddiqui et al. Korean J Anesthesiol. 2016 Apr.

Abstract

Background: Spinal anesthesia with bupivacaine, typically used for elective and emergency cesarean section, is associated with a significant incidence of hypotension resulting from sympathetic blockade. A variety of dosing regimens have been used to administer spinal anesthesia for cesarean section. The objective of this study was to compare the incidence of hypotension following two different fixed dosing regimens.

Methods: This was a randomized double-blind clinical trial with a two-sided design, 5% significance level and 80% power. After approval of the hospital ethics review committee, 60 patients were divided randomly into two groups. In one group, the local anesthetic dose was adjusted according to height and weight, and in the other, the dose was adjusted according to height only.

Results: Sixty women with a singleton pregnancy were included. Of the factors that could affect dose and blood pressure, including age, weight, height, and dose, only height differed between the groups. Mean heart rate was similar between the groups. Hypotension was significantly more frequent with dosage based on height alone than with two-factor dose calculation (56.7% vs. 26.7%; P = 0.018).

Conclusions: Adjusting the dose of isobaric bupivacaine to a patient's height and weight provides adequate anesthesia for elective cesarean section and is associated with a decreased incidence and severity of maternal hypotension and less use of ephedrine.

Keywords: Body height; Body weight; Caesarean section; Local anesthetics; Spinal anesthesia.

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Figures

Fig. 1
Fig. 1. Comparison of mean heart rate between patients receiving anesthesia dosages based on height and weight (n = 30, triangles, solid line) and those whose dose was calculated based on height alone (n = 30, circles, dotted line). Error bars are 95% confidence intervals. No difference was observed between groups but a significant difference was observed from baseline *P < 0.05 in the height-weight group and P < 0.05 in the height-alone group.
Fig. 2
Fig. 2. Comparison of mean arterial pressure (MAP) between patients receiving anesthesia dosages based on height and weight (n = 30, triangles, solid line) and those whose dose was calculated based on height alone (n = 30, circles, dotted line). Error bars are 95% confidence intervals. No difference was observed between the groups but a significant difference was observed from baseline *P < 0.05 in the height-weight group and P < 0.05 in the height-alone group.
Fig. 3
Fig. 3. Comparison of complications between the groups.

References

    1. Michie AR, Freeman RM, Dutton DA, Howie HB. Subarachnoid anaesthesia for elective caesarean section. A comparison of two hyperbaric solutions. Anaesthesia. 1988;43:96–99. - PubMed
    1. Chung CJ, Bae SH, Chae KY, Chin YJ. Spinal anaesthesia with 0.25% hyperbaric bupivacaine for Caesarean section: effects of volume. Br J Anaesth. 1996;77:145–149. - PubMed
    1. Rout CC, Akoojee SS, Rocke DA, Gouws E. Rapid administration of crystalloid preload does not decrease the incidence of hypotension after spinal anaesthesia for elective caesarean section. Br J Anaesth. 1992;68:394–397. - PubMed
    1. Corke BC, Datta S, Ostheimer GW, Weiss JB, Alper MH. Spinal anaesthesia for Caesarean section. The influence of hypotension on neonatal outcome. Anaesthesia. 1982;37:658–662. - PubMed
    1. Marx GF, Cosmi EV, Wollman SB. Biochemical status and clinical condition of mother and infant at cesarean section. Anesth Analg. 1969;48:986–994. - PubMed

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