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

Determination of ED90s of Phenylephrine and Norepinephrine Infusion for Prevention of Spinal Anesthesia-Induced Hypotension in Patients with Preeclampsia During Cesarean Delivery

Background

Vasopressors remain an important strategy for managing spinal anesthesia-induced hypotension in women with preeclampsia. The aim of this study was to investigate the ED90s and efficacy ratio of phenylephrine and norepinephrine in managing spinal anesthesia-induced hypotension in women with preeclampsia during cesarean delivery.

Methods

60 women with preeclampsia, who underwent cesarean delivery, were randomly assigned to receive either a continuous intravenous infusion of phenylephrine or norepinephrine following spinal anesthesia. The initial dosage of phenylephrine or norepinephrine for the first women was 0.5 or 0.05 μg/kg/min, respectively, and subsequent infusion dosages were adjusted based on their efficacy in preventing spinal anesthesia-induced hypotension (defined as a systolic blood pressure less than 80% of the baseline level). The incremental or decremental doses of phenylephrine or norepinephrine were set at 0.1 or 0.01 μg/kg/min. The primary outcomes were the ED90s and efficacy ratio of phenylephrine and norepinephrine infusions for preventing spinal anesthesia-induced hypotension prior to delivery.

Results

The results obtained from isotonic regression analysis revealed that the ED90 values of the phenylephrine and norepinephrine group for preventing spinal anesthesia-induced hypotension were 0.597 (95% CI: 0.582-0.628) and 0.054 (95% CI: 0.053-0.056) μg/kg/min, respectively, with an efficacy ratio of 11.1:1. The results of Probit regression analysis revealed that the ED90 values were determined to be 0.665 (95% CI: 0.576-1.226) and 0.055 (95% CI: 0.047-0.109) μg/kg/min, respectively, with an efficacy ratio of 12.1:1.

Conclusion

The administration of 0.6 μg/kg/min phenylephrine and 0.05 μg/kg/min norepinephrine has been found to effectively manage a 90% incidence of spinal anesthesia-induced hypotension in women with preeclampsia.

Dose-Response Study of Norepinephrine Infusion for Maternal Hypotension in Preeclamptic Patients Undergoing Cesarean Delivery Under Spinal Anesthesia

BACKGROUND AND OBJECTIVE

Spinal anesthesia remains the preferred mode of anesthesia for preeclamptic patients during cesarean delivery. We investigated the incidence of maternal hypotension under spinal anesthesia during cesarean delivery, by comparing different prophylactic infusion rates of norepinephrine with normal saline.

METHODS

We randomly allocated 180 preeclamptic patients (45 in each groups) aged 18-45 scheduled for cesarean delivery to receive one of four prophylactic norepinephrine infusions at doses of 0 (normal saline group), 0.025 (0.025 group), 0.05 (0.05 group), or 0.075 (0.075 group) µg/kg/min following spinal anesthesia. The primary endpoint was the incidence of maternal hypotension (systolic blood pressure < 80% of baseline).

RESULTS

The incidence of maternal hypotension was reduced with different prophylactic infusion rates of norepinephrine (26.7%, 15.6%, and 6.7%) compared with normal saline (37.8%) with a significant decreasing trend (p = 0.002). As the infusion doses of norepinephrine increased, there is a significant decreasing trend in deviation of systolic blood pressure control (median performance error; median absolute performance error) from baseline (p < 0.001; p < 0.001) and need for rescue norepinephrine boluses (p = 0.020). The effective dose 50 and effective dose 90 of prophylactic norepinephrine infusion were - 0.018 (95% confidence interval - 0.074, 0.002) µg/kg/min and 0.065 (95% confidence interval 0.048, 0.108) µg/kg/min, respectively.

CONCLUSIONS

Prophylactic infusion of norepinephrine, as compared to no preventive measures, can effectively reduce the incidence of maternal hypotension in preeclamptic patients under spinal anesthesia during cesarean delivery, without increasing other adverse events for either the mother or neonate.

REGISTRATION

Clinical trials.gov identifier number NCT04556370.

Anesthetic Conversion of Preexisting Labor Epidural Analgesia for Emergency Cesarean Section and Efficacy of Levobupivacaine with or Without Magnesium Sulphate: A Prospective Randomized Study

Background: For pregnant women who require an emergency cesarean section (CS), extending labor epidural analgesia as quickly as feasible to good quality anesthesia is a critical issue. This indicates the presence of functional labor epidural analgesia and reduces the need for general anesthesia. Addition of magnesium increases anesthetic and analgesic qualities of epidural anesthesia. Objectives: The purpose of this trial was to assess the role of adding magnesium sulfate (MgSO4) with levobupivacaine to speed up the conversion of labor epidural analgesia into enough anesthesia for emergency CS. Methods: Fifty parturients were randomly assigned to receive 19.5 mL of levobupivacaine 0.5% with either 0.5 mL of normal saline 0.9% (Group I) or 0.5 mL of MgSO4 10% (Group II) after receiving labor epidural analgesia. We documented the onset of block (loss of pinprick to T6), number of patients needing additional analgesia, the time needed for sensory and motor blockade to recover, and the adverse effects. Results: The frequency of patients receiving intraoperative supplements was comparable in the study groups (P = 0.491), although the onset of the block was faster in Group II than in Group I (P = 0.000*). Group II took substantially longer to recover from sensory and motor blockade than Group I (P = 0.001* and P = 0.001*, respectively). In both groups, the occurrence of adverse events was similar. Conclusions: Adding 50 mg of MgSO4 to levobupivacaine 0.5% accelerated the epidural top, and both sensory onset and motor blocks period were prolonged as compared to levobupivacaine alone when extending epidural analgesia for emergency CS.

Pre-operative Ultrasonographic Evaluation of the Internal Jugular Vein Collapsibility Index and Inferior Vena Cava Collapsibility Index to Predict Post Spinal Hypotension in Pregnant Women Undergoing Caesarean Section

Background: Post spinal anesthesia hypotension (PSAH) is frequently encountered in anesthetic practice, especially during cesarean section. Ultrasound is a safe and easy technique for hemodynamic monitoring. Objectives: This study was conducted to assess the efficacy of pre-operative inferior vena cava collapsibility index (IVCCI) and internal jugular vein collapsibility index (IJVCI) in predicting PSAH. Methods: This cross-sectional blinded study included 55 pregnant females prepared for elective cesarean section. They were divided into two groups based on the incidence of PSAH: (1) cases with PSAH (26 cases); and (2) cases without PSAH (29 cases). All the cases underwent ultrasound-guided measurement of IVCCI and IJVCI. The efficacy of these parameters was assessed in predicting PSAH. Results: Cases in both groups expressed non-significant differences regarding demographic data. However, IVCCI had mean values of 38.27 and 23.97%, while IJVCCI had mean values of 46.50 and 33.41%, respectively, in cases with and without PSAH. For IVCCI, using a cut-off point of 33% had sensitivity and specificity (84.6 and 93.1%, respectively) for predicting PSAH, with a diagnostic accuracy of 89.1%. IJVCI had sensitivity and specificity of 84.6 and 82.8%, respectively, for predicting the same complication using a cut-off value of 38.5%. Conclusion: IVCCI and IJVCI are efficacious and reliable tools in predicting PSAH in pregnant ladies undergoing cesarean section, with a slight superiority for IVCCI regarding specificity and accuracy.

Comparison of three neuraxial anesthesia approaches in parturient women with obesity and pregnancy-induced hypertension who underwent cesarean section

OBJECTIVE

To compare the effectiveness of different approaches of neuraxial anesthesia in parturient women with obesity and pregnancy-induced hypertension (PIH) who undergo cesarean section (CS).

METHODS

We retrospectively analyzed data from 108 parturient women with obesity and PIH who underwent CS. All women were divided into the following three groups according to the neuraxial anesthesia approach: spinal anesthesia (SA), epidural anesthesia (EA), and combined spinal-epidural anesthesia (CSE). Clinical variables were compared.

RESULTS

The mean age of the patients was 27.3 ± 2.2 years. Women in the CSE group had a longer duration from puncture to surgery, smaller intraoperative change in mean arterial pressure, higher Apgar scores at 1 and 5 minutes, shorter surgery time, lower rates of nausea and vomiting, and lower rate of intraoperative hypotension compared with those in the SA and EA groups.

CONCLUSION

CSE takes longer to administer in parturient women with obesity and PIH who undergo CS compared with those who have SA or EA. However, CSE has several advantages over SA or EA, including a shorter surgery time, more stable intraoperative mean arterial pressure, lower rates of nausea, vomiting, and intraoperative hypotension, and better Apgar scores at 1 and 5 minutes.

Effectiveness of Spinal Analgesia for Labor Pain Compared with Epidural Analgesia

Objectives

This study aimed to compare the analgesic effect of single-dose spinal versus epidural analgesia for labor pain to verify if applying a single dose spinal analgesia is an efficient technique for labor pain management as an alternative for epidural analgesia.

Methods

A total of 128 women in the active phase of labor were randomly allocated into two groups of spinal analgesia (n = 64) and epidural analgesia (n = 64). The latter received a bolus dose of 16 mL of 0.125% bupivacaine and 50 μg fentanyl and repeated 5 - 10 mL of bolus dose. The former received 2.5 mg hyperbaric bupivacaine plus 50μg fentanyl. Pain intensity was measured using the visual analog scale (VAS). The duration of analgesia, mode of delivery, the duration of labor, side effects, and maternal satisfaction were also compared.

Results

There were no significant differences in the rate of cesarean section, duration of labor, postpartum hemorrhage, and the frequency of the fetal heart deceleration until 30 min after analgesia between the two groups. Measured pain after 30 (P = 0.0001) and 90 min (P = 0.01) was significantly lower in the spinal group than the epidural group. However, there was no significant difference between the spinal and epidural groups concerning the VAS scores at 150, 210, and 270 minutes. Maternal satisfaction was higher in the spinal group (P = 0.002). The mean duration of analgesia was longer in the spinal group than the epidural group (P = 0.0001).

Conclusions

According to the findings, single-dose spinal analgesia, compared to epidural analgesia, is a safe, fast, and efficient technique for labor analgesia, which can be easily performed. In addition, it provides a high satisfaction level in the parturient.

Comparative Study of Effect of Spinal Anesthesia in Sitting and Lateral Positions on the Onset Time of Sensory Block and Hemodynamic Condition in Cesarean Section: A Randomized Clinical Trial

BACKGROUND

Spinal anesthesia is the method of choice for the cesarean section. Hypotension is a common complication of this method.

OBJECTIVES

This study aimed to compare the effect of spinal anesthesia in the sitting and lateral positions on the onset time of sensory block and hemodynamic condition in cesarean sections.

METHODS

In this clinical trial, 106 elective cesarean section candidates under spinal anesthesia were selected and randomly divided into two groups: spinal anesthesia in the sitting position (group S) and the lateral position (group L). The onset time of the sensory block, quality of sensory and motor block, hemodynamic condition, frequency of hypotension, nausea, and vomiting, and the doses of ephedrine and atropine were compared between both groups. Data were analyzed with SPSS version 16 software at a 95% confidence level.

RESULTS

There was no statistically significant difference between the two groups in terms of age. The frequency of hypotension in L and S groups was 24.5% and 57.7%, respectively (P = 0.001), in minute 6 after spinal anesthesia and 5.7% and 36.5%, respectively (P < 0.001), in minute 8 after spinal anesthesia. The mean time to reach the sensory level of T6 was 1.30 ± 0.43 min versus 4.54 ± 2.12 min (P < 0.001), motor block score in minute 5 was 2.98 ± 0.14 versus 2.82 (P = 0.044), and ephedrine dose was 11.5 mg and 16.92 mg in the L and S groups, respectively (P = 0.010). The maximum sensory-motor block and satisfaction of women with spinal anesthesia were significantly higher in the lateral position than in the sitting position (P < 0.05).

CONCLUSIONS

Cesarean sections under spinal anesthesia in the lateral position than in the sitting position lead to a more rapid sensory and motor block, reduced ephedrine consumption, and enhanced satisfaction of women.