Comparison of fractionated dose versus bolus dose injection in spinal anaesthesia for patients undergoing elective caesarean section: A randomised, double-blind study

Fractional spinal anaesthesia in high-risk elderly patients for orthopaedic surgery - Case series

Elderly patients coming for orthopaedic surgeries usually have many comorbidities. This makes them potentially vulnerable to haemodynamic instability with a conventional bolus dose of spinal anaesthetic. Fractionating the spinal dose was reported to have haemodynamic stability with a longer duration. Here, we present five cases of high-risk elderly patients with multiple comorbidities who presented for orthopaedic surgeries and were successfully managed with fractional spinal anaesthesia.

A Comparison of the Effect of Fractionated and Bolus Dose Injection on Spinal Anesthesia for Lower Limb Surgery: A Randomized Clinical Trial

Background

In previous clinical trials and a small number of studies, the fractional injection of anesthetics led to reduced physiological complications and hemodynamic stability and increased duration of anesthesia.

Objectives

The present study intended to compare the effect of fractionated and bolus dose injection of bupivacaine and fentanyl on spinal anesthesia for lower limb fracture surgeries.

Methods

In this randomized, double-blind clinical trial, 70 patients with lower limb fractures were divided into groups of bolus spinal anesthesia (Group A) and fractional spinal anesthesia (Group B). Group A received a bolus dose of 25 μg fentanyl plus 15 mg bupivacaine 0.5% intrathecally at a rate of 0.2 mL/sec and were laid down in supine position after 45 seconds. In Group B, a half dose of the mixture, i.e., 25 μg fentanyl plus 15 mg bupivacaine 0.5% mixture, was injected intrathecally, and then, the other half was injected after 45 seconds while the needle was still in place. Afterward, the patients were immediately laid down in the supine position. Hemodynamic changes in the sensory and motor blockage parameters were recorded in both groups.

Results

The motor blockage onset time was shorter in Group B compared to Group A (P = 0.026). Moreover, the sensory blockage duration was longer (P = 0.035), and the highest level of sensory blockage was lower (P = 0.008) in Group B compared to Group A.

Conclusions

Fractional spinal anesthesia led to a longer duration and more favorable levels of sensory blockage compared to the bolus method. In addition, hemodynamic changes and complications occurred less frequently following this procedure.

A Comparative Study of Fractionated Versus Single Dose Injection for Spinal Anesthesia During Cesarean Section in Patients with Pregnancy-Induced Hypertension

Background

Local anesthetics for spinal anesthesia in one-single injection are known to induce more severe hypotension than a fractionated dose in healthy obstetric patients. Hypotension in obstetric patients with pregnancy-induced hypertension, including preeclampsia, during spinal anesthesia, could compromise fetal well-being.

Objectives

This study aimed to compare the mean arterial pressure (MAP), the total dose of ephedrine required, and level of sensory blockade between the fractionated-dose and single-dose spinal anesthesia injection in obstetric patients with pregnancy-induced hypertension who underwent a cesarean section.

Methods

This single-blind randomized clinical trial was conducted from January to April 2018 after being approved by the Research Ethics Committee of Universitas Indonesia (No. 1174/UN2.F1/ETIK/2017) and recorded at ClinicalTrials.gov (NCT03693638). After obtaining informed consent, 42 parturients with hypertension in pregnancy (gestational hypertension or preeclampsia), ASA II-III, aged 18 - 40 years, and BMI of 18.5 - 35 kg/m² with singleton pregnancy, who were planned for spinal anesthesia for emergency or semi-emergency cesarean section with hyperbaric bupivacaine 0.5% (Marcaine^TM, Hospira) and fentanyl, were included in this study. All subjects were randomly divided into two groups including fractionated-dose (FD) and single-dose (SD).

Results

There was no significant difference between the two groups in MAP in the first 15 minutes after anesthesia (P > 0.05) and median total dose of ephedrine required (10 (0 - 25) mg in the FD group vs. 15 (0 - 30) mg in the SD group, P = 0.30). However, in the FD group, MAP tended to be higher in the first three minutes compared to the SD group. The level of sensory blockade was mostly at T4, which was not significantly different between the groups (52.4% in FD vs. 42.9% in SD, P = 0.59).

Conclusions

In obstetric patients with pregnancy-induced hypertension who underwent a cesarean section, the mean arterial pressure after spinal anesthesia was not significantly different between the fractionated dose of spinal anesthesia injection and single-dose injection. Total ephedrine required and levels of sensory blockade were not significantly different between the groups.