Comparing the Hemodynamic Effects of Spinal Anesthesia in Preeclamptic and Healthy Parturients During Cesarean Section

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.

Comparison of Ropivacaine versus Bupivacaine in Spinal-Induced Hypotension in Preeclampsia Patients: A Randomized Control Trial

Background

Spinal anesthesia is considered to be the safest method of anesthesia for cesarean sections in patients with preeclampsia. Patients with preeclampsia are at an increased risk of experiencing severe hypotension following spinal anesthesia, which could have more profound and deleterious effects on both the fetus and the mother. However, bupivacaine, the most commonly used drug, can induce severe hypotension even at low doses. The purpose of this study is to minimize post-spinal hypotension in both the mother and the fetus.

Objectives

To determine and compare the reduction in hypotension following spinal anesthesia in patients with preeclampsia between the ropivacaine and bupivacaine groups.

Methods

In a randomized clinical trial, a total of 90 parturients with preeclampsia undergoing spinal anesthesia were enrolled and randomly divided into 2 groups: One receiving ropivacaine and the other receiving bupivacaine. The dose of spinal ropivacaine was 15 mg of a 0.5% solution, and the dose of bupivacaine was also 15 mg of a 0.5 % solution. Hemodynamic parameters, including systolic and diastolic blood pressure and heart rate, were recorded following the administration of spinal anesthesia. Pain scores and the time until the return of motor movement were also documented.

Results

For statistical analysis, the t-test, Chi-square, and ANOVA tests were utilized to compare the groups. Demographic variables, including maternal age, gestational age, parity, and gravidity, were not significantly different between the 2 groups. The trend of mean systolic blood pressure (SBP) was significantly lower in the bupivacaine group compared to the ropivacaine group at all measured time points in the study (P < 0.05). The amount of ephedrine used after spinal anesthesia was significantly different at 2 and 4 minutes in the ropivacaine group compared to the bupivacaine group (P = 0.012, P = 0.025). Post-operative pain scores at 1 hour in recovery were not significantly different between the ropivacaine and bupivacaine groups (P = 0.015). The time to knee movement was also significantly shorter in the ropivacaine group compared to the bupivacaine group (P < 0.001).

Conclusions

Ropivacaine reduces the incidence of hypotension in spinal anesthesia compared to bupivacaine for cesarean section in patients with preeclampsia. This is attributed to a lower occurrence of spinal-induced hypotension, improved hemodynamic control, reduced ephedrine usage, and faster patient ambulation. A future study could focus on investigating different dosages of both drugs with a larger number of participants.

A Five-Year Retrospective Closed Cohort Study to Find a Superior Anaesthetic Technique for Caesarean Section From a Haemodynamic Perspective

Background A cesarean section (CS) is common and requires a safe and effective anesthetic technique for the safety of both the mother and the fetus. This study aims to compare the intraoperative hemodynamic safety profile with general anesthesia (GA) and regional anesthesia (RA) and propose a superior technique for cesarean from the hemodynamic perspective. Methods After obtaining ethical committee approval, a retrospective closed cohort study was conducted on patients who underwent cesarean with GA and RA. This study was conducted at a tertiary-level university hospital in Oman from January 2015 to December 2019. The investigators collected maternal and fetal data (hypotension, bradycardia, blood loss, APGAR score, fetal mortality, complications, and length of stay) from January 2015 to December 2019. The primary outcome was the incidence of intraoperative hypotension, and the secondary outcomes studied were significant blood loss and APGAR score in both anesthesia techniques. Results A total of 2500 cesarean patients were studied, of whom 1379 received RA and 1121 received GA. The overall hypotension (systolic BP<90 mm Hg) rate observed was 40.1%; it was significantly lower with GA as compared to RA (32.1% versus 46.5%, respectively, P<0.001, OR 0.545, 95% CI 0.462 to 0.643). Consequently, the requirement for vasopressors was low with GA compared to RA (1.6% versus 23.1%, P<0.001, OR 0.054, 95% CI 0.034 to 0.088). Blood loss (>1 L) was remarkably higher in GA as compared to the RA (15.5% versus 8.9%, respectively, P<0.001, OR 1.916, 95% CI 1.499 to 2.448). APGAR scores were lower with GA than RA (2.8% versus 0.9%, P<0.001). Bradycardia and fetal mortality were almost equal in both groups. Conclusion GA is associated with significantly better hemodynamic stability during the cesarean section.

Comparison of the hemodynamic changes between preeclamptic and normotensive parturients who underwent cesarean section under spinal anesthesia at North Showa zone public hospitals, Oromia region, Ethiopia, 2022: a prospective cohort study

BACKGROUND

Spinal anaesthesia complicates maternal hemodynamic and may expose the parturient to dangerous cardiovascular problems. Up to 7% to 89.2% of pregnant women can suffer from spinal anaesthesia-related hypotension. The aim of this study to compare the hemodynamic changes between preeclamptic and normotensive parturients who underwent caesarean section under spinal anaesthesia at North Showa Zone Public Hospitals, Oromia Region, from February 15 to May 15, 2022.

METHODS

A prospective cohort study was conducted on a total of 140 parturients (70 in each group) who underwent cesarean delivery under spinal anesthesia. The study participants were chosen using a consecutive sampling technique. Data were collected from patient charts and intraoperative observations and entered into the Epi Data software version 4.6 and exported to the Statistical Package for the Social Sciences version 25 software. Hemodynamic change = (baseline value-current value/baseline value) * 100. The independent t-test, Mann-Whitney U test, two ways mixed ANOVA, chi-square, and Fisher's exact test was used to analyze the data as appropriate. A P < 0.05 was statistically significant.

RESULTS

The mean percentage change in SBP, DBP, and MAP after spinal anaesthesia was a statistically significant difference between the normotensive and preeclamptic groups, except MAP at 15 min was comparable between the two groups with p = 0.638. The proportion of preeclamptic parturients who develop hypotension was 47%, compared to 74% of normotensive parturients, and the RR of developing hypotension, if participants were preeclamptic, was 0.63, with a 95% confidence interval of 0.412 to 0.978 and a p = 0.039. The mean change in heart rate during the first 15 min was comparable between the groups.

CONCLUSION

In contrast to normotensive parturients undergoing caesarean section under spinal anaesthesia, our study found that the hemodynamic change was lower in preeclamptic parturients. The proportion of preeclamptic women who develop hypotension was 47%, compared to 74% of normotensive parturients.

Comparison of hemodynamic changes and fetal outcome between normotensive and preeclamptic parturient undergoing elective cesarean section under spinal anesthesia: A prospective observational cohort study

Background

Objective

Methodology

Results

Conclusion

•

Peak sensory block level was similar in both groups and no patients complained intraoperative pain and analgesics were not required supplemental.

•

Base line SBP, DBP and MAP were significantly higher in severe preeclamptic group (p = 0.01).

•

Mean gestational age of the fetus was significantly low in severe preeclamptic group (p = 0.01).

•

Apgar score at 1st min(7–8 vs,8–9),volume of intra operative fluid use were statistically significant with p < 0.05

A Clinical Trial on the Effects of Different Regimens of Phenylephrine on Maternal Hemodynamic After Spinal Anesthesia for Cesarean Section

Background

Phenylephrine is used to prevent and treat hypotension during spinal anesthesia for cesarean delivery.

Objectives

The present study aims to investigate the effects of different regimens of phenylephrine on blood pressure of candidates for the cesarean section.

Methods

In this double-blind, randomized clinical trial, a total of 120 candidates of elective cesarean delivery under spinal anesthesia was randomly categorized into three groups. Groups 1, 2, and 3 received bolus and prophylactic saline (control group), prophylactic bolus phenylephrine (100 µg), and prophylactic phenylephrine infusion (50 µg/min), respectively. The incidence of hypotension, maternal hemodynamics, hypertension, rescue phenylephrine dose, nausea, and vomit were compared between the groups.

Results

In all the three groups, the incidence of nausea and vomit, bradycardia, hypertension, and neonatal Apgar score were not statistically different (P > 0.05). However, the adjuvant phenylephrine dose requirement was remarkably different. Moreover, the mean systolic blood pressure differed significantly in the second and 7th minutes after the spinal block (P < 0.05). 35% in the first group, 15% in the second group, and 2.5% in the third group had hypotension (P = 0.001). Apart from the first measurement after spinal anesthesia, the mean heart rate showed no significant difference between the groups.

Conclusions

The use of prophylactic phenylephrine infusion is recommended to control the optimal blood pressure in parturients undergoing cesarean section after spinal anesthesia.

Hemodynamic changes after spinal anesthesia in preeclamptic patients undergoing cesarean section at a tertiary referral center in Ethiopia: a prospective cohort study

Background

Spinal anesthesia-induced maternal hypotension is the most frequent complication associated with maternal morbidity and mortality during Cesarean section. The aim of this study was to compare the incidence and magnitude of hemodynamic changes in preeclamptic and non-preeclamptic parturients undergone Cesarean section under spinal anesthesia.

Method

A prospective cohort study was conducted from 01 February to 28 May 2019 in preeclamptic and non-preeclamptic parturients. We hypothesized preeclamptic parturients are at high risk of spinal anesthesia induced hypotension than non preeclamptics. A total of 122 ASA II and ASA III parturients were recruited consecutively and assigned to two groups (81non-preeclamptics, and 41 preeclamptics). Parturients with cardiac disease, twin pregnancy, chronic hypertension, gestational hypertension, superimposed hypertension, renal disease, diabetes mellitus, coagulopathy (platelet count < 80 × 10⁹/L), active labor, eclampsia, abruptio placentae, placenta praevia, any adjuvant added with local anesthetics were excluded. The data analysis was done using SPSS version 22 statistical software. Student t test, MannWhitney U test and Fisher exact test were used to compare the data. All P values < 0.05 were considered statistically significant.

Result

The incidence of spinal anesthesia-induced hypotension was higher in non-preeclamptic parturients than preeclamptic parturients (55.6% vs. 34.1%, respectively) and the degree of blood pressure drop was significantly greater in the non-preeclamptic parturients compared to those with preeclampsia; As well intraoperative fluid consumption was significantly greater in the non-preeclamptics parturients compared to those with preeclamptics.

Conclusion

The incidence and magnitude of spinal anesthesia-induced hypotension in parturients undergone Cesarean section were less in preeclamptic parturients than in non-preeclamptic parturients.. Based on the data from this study we recommended spinal anesthesia for preeclamptic patients, unless there is a contra indication based on preeclampsia.

Spinal-Induced Hypotension in Preeclamptic and Healthy Parturients Undergoing Cesarean Section

BACKGROUND

There is a widespread belief that spinal anaesthesia in patients with preeclampsia might cause severe hypotension and decreased uteroplacental perfusion. This study aimed to evaluate the incidence and severity of spinal induced-hypotension in preeclamptics and healthy parturients.

METHODS

Total of 78 patients (40 healthy and 38 preeclamptic) undergoing a C-Section with spinal anaesthesia were included. Spinal anaesthesia was performed with a mixture of 8-9 mg isobaric 0.5% bupivacaine, 20 mcg fentanyl and 100 mcg morphine (total volume 2.2-2.4 ml). Blood pressures (BP)-SBP, DBP, MAP were recorded non-invasively before performing spinal anaesthesia and at 2.5 minutes after a spinal puncture.

RESULTS

The BP falls (%) from baseline were significantly greater in the healthy parturients compared to those with preeclampsia (25.8% ± 10.1 vs 18.8% ± 17.0 for SBP, 28.5% ± 8.8 vs 22.5% ± 10.4 for DBP, and 31.2% ± 14.2 vs 18.2% ± 12.6% for MAP, p < 0.05). The incidence rate of hypotension in the preeclamptics was 25% compared to 53% in healthy parturients (p < 0.001). Higher doses of vasopressors both ephedrine (16.5 ± 8.6 vs 6.0 ± 2.0 mg) and phenylephrine (105 ± 25 mg) in the healthy women were required. There was no need for phenylephrine treatment in the preeclamptic group.

CONCLUSION

This study showed that the incidence and severity of spinal-induced hypotension in preeclamptic patients are less than in healthy women. The use of low dose spinal anaesthesia also contributed to this statement.

Comparison of the effects of low doses of dexmedetomidine and remifentanil on the maternal hemodynamic changes during caesarean delivery in patients with severe preeclampsia: a randomized trial

BACKGROUND

Preoperative remifentanil administration blunts hemodynamic responses to tracheal intubation in parturients with severe preeclampsia. We hypothesized that the preoperative administration of low doses of remifentanil or dexmedetomidine would lead to comparable maternal neurohormonal responses and neonatal outcomes in patients with severe preeclampsia.

METHODS

Parturients diagnosed with severe preeclampsia undergoing caesarean delivery were randomLy allocated to receive remifentanil (0.1 µg/kg/min) or dexmedetomidine (0.4 µg/kg/h) at five min and 20 min before induction, respectively. Changes in maternal mean arterial BP(MAP), clinical recovery, cortisol level, and neonatal outcome, were recorded.

RESULTS

Patients who received remifentanil had higher response in MAP at the induction (94 9.8 vs. 104 4.5; P<0.001) and emergence from anesthesia (94 6.3 vs. 98 5.1; P<0.001), but shorter times to extubation (5.1 1.6 vs. 13.5 2.8 min; P<0.001). Five (27.8%) patients in the remifentanil group received ephedrine versus none in the dexmedetomidine group (P=0.023). The maternal plasma cortisol levels, the neonatal Neurologic and Adaptative Capacity Scores and acid-base satuses were similar in the two groups. Newborns in the remifentanil group presented lower Apgar scores at 1 minute (5.11 0.8 vs. 5.68 0.8; P=0.034) and a higher incidence of respiratory depression (72.2% vs. 36.8% P=0.048).

CONCLUSIONS

Compared with dexmedetomidine (0.4 µg/kg/h), the preoperative administration of remifentanil (0.1 µg/kg/min) produced a significantly higher effect on maternal hemodynamic responses to caesarean delivery in patients with severe preeclampsia, however maternal hypotension and neonatal respiratory depression were more common with the use of remifentanil.

Relation with postpartum maternal morbidity of different types of anesthesia in preeclamptic patients

OBJECTIVE

The aim of this study is to investigate the effect of different anesthesia types administered to patients with preeclampsia on postoperative maternal morbidities.

METHODS

Medical records of pregnant women complicated with preeclampsia delivered by cesarean from January 2010 to December 2016 in our clinic were retrospectively reviewed.

RESULTS

There was not a statistically significant difference between patients receiving spinal anesthesia and general anesthesia in terms of additional parenteral analgesic requirement at postoperative period (p = 0.520). The length of stay in hospital and δHb (preoperative hemoglobin value minus postoperative hemoglobin value) were not different between spinal anesthesia and general anesthesia groups (p = 0.140 and 0.648, respectively). The rate of postoperative antihypertensive medication requirement was statistically significant in patients with severe preeclampsia who underwent general anesthesia (p = 0.009, x² = 6.867, odds ratios = 4.276 (1.531-11.942)). The time passing to reach the first normal blood pressure level in patients with severe preeclampsia was 11.95 ± 9.11 h in patients with spinal anesthesia, 10.55 ± 4.95 h in patients with general anesthesia, and the difference was not statistically significant (p = 0.504).

CONCLUSION

The need for antihypertensive medication is greater in patients with severe preeclampsia receiving general anesthesia. There is a need for comprehensive, prospective, and randomized controlled trials to establish the relationship between postpartum morbidity and the different types of anesthesia.

Comparison of Phenylephrine and Ephedrine in Treatment of Spinal-Induced Hypotension in High-Risk Pregnancies: A Narrative Review

Purpose

To compare maternal and fetal effects of intravenous phenylephrine and ephedrine administration during spinal anesthesia for cesarean delivery in high-risk pregnancies.

Source

An extensive literature search was conducted using the US National Library of Medicine, MEDLINE search engine, Cochrane review, and Google Scholar using search terms “ephedrine and phenylephrine,” “preterm and term and spinal hypotension,” “preeclampsia and healthy parturients,” or “multiple and singleton gestation and vasopressor.” Society of Obstetric Anesthesia and Perinatology meeting abstracts for the past 4 years were also searched for relevant studies.

Principle findings

Both phenylephrine and ephedrine can be safely used to counteract hypotension after spinal anesthesia in patients with uteroplacental insufficiency, pregnancy-induced hypertension, and in non-elective cesarean deliveries. Vasopressor requirements before delivery in high-risk cesarean sections are reduced compared to healthy parturients. Among the articles reviewed, there were no statistically significant differences in umbilical arterial pH, umbilical venous pH, incidence of fetal acidosis, Apgar scores, or maternal hypotension when comparing maternal phenylephrine and ephedrine use.

Conclusion

From the limited existing data, phenylephrine and ephedrine are both appropriate selections for treating or preventing hypotension induced by neuraxial blockade in high-risk pregnancies. There is no clear evidence that either medication is more effective at maintaining maternal blood pressure or has a superior safety profile in this setting. Further investigations are required to determine the efficacy, ideal dosing regimens, and overall safety of phenylephrine and ephedrine administration in high-risk obstetric patients, especially in the presence uteroplacental insufficiency.