Crystalloid Coload Reduced the Incidence of Hypotension in Spinal Anesthesia for Cesarean Delivery, When Compared to Crystalloid Preload: A Meta-Analysis

Predicting fluid responsiveness in spontaneously breathing parturients undergoing caesarean section via carotid artery blood flow and velocity time integral measured by carotid ultrasound: a prospective cohort study

BACKGROUND

Present evidence suggests that the Doppler ultrasonographic indices, such as carotid artery blood flow (CABF) and velocity time integral (VTI), had the ability to predict fluid responsiveness in non-obstetric patients. The purpose of this study was to assess their capacity to predict fluid responsiveness in spontaneous breathing parturients undergoing caesarean section and to determine the effect of detecting and management of hypovolemia (fluid responsiveness) on the incidence of hypotension after anaesthesia.

METHODS

A total of 72 full term singleton parturients undergoing elective caesarean section were enrolled in this study. CABF, VTI, and hemodynamic parameters were recorded before and after fluid challenge and assessed by carotid artery ultrasonography. Fluid responsiveness was defined as an increase in stroke volume index (SVI) of 15% or more after the fluid challenge.

RESULTS

Thirty-one (43%) patients were fluid responders. The area under the ROC curve to predict fluid responsiveness for CABF and VTI were 0.803 (95% CI, 0.701-0.905) and 0.821 (95% CI, 0.720-0.922). The optimal cut-off values of CABF and VTI for fluid responsiveness was 175.9 ml/min (sensitivity of 74.0%; specificity of 78.0%) and 8.7 cm/s (sensitivity of 67.0%; specificity of 90.0%). The grey zone for CABF and VTI were 114.2-175.9 ml/min and 6.8-8.7 cm/s. The incidence of hypotension after the combined spinal-epidural anaesthesia (CSEA) was significantly higher in the Responders group 25.8% (8/31) than in the Non-Responders group 17.1(7/41) (P < 0.001). The total incidence of hypotension after CSEA of the two groups was 20.8% (15/72).

CONCLUSIONS

Ultrasound evaluation of CABF and VTI seem to be the feasible parameters to predict fluid responsiveness in parturients undergoing elective caesarean section and detecting and management of hypovolemia (fluid responsiveness) could significantly decrease incidence of hypotension after anaesthesia.

TRIAL REGISTRATION

The trial was registered at the Chinese Clinical Trial Registry (ChiCTR) ( www.chictr.org ), registration number was ChiCTR1900022327 (The website link: https://www.chictr.org.cn/showproj.html?proj=37271 ) and the date of trial registration was in April 5, 2019. This study was performed in accordance with the Declaration of Helsinki and approved by the Research Ethics Committee of Women's Hospital, Zhejiang University School of Medicine (20,180,120).

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 the effects of general and spinal anesthesia for cesarean delivery on maternal and fetal outcomes: A retrospective analysis of data

OBJECTIVE

General or single-shut spinal anesthesia (SA) is applied for cesarean section and both methods of anesthesia have different effects on the mother and newborn. This retrospective study, in which 1-year data were analyzed, was aimed to examine the effects of general or SA on maternal and neonatal outcomes.

METHODS

Anesthesia technique, mother's age, gestational age, number of pregnancies, previous cesarean delivery number, maternal complications, and indications for cesarean delivery were analyzed in 883 cesarean deliveries. In addition, weight and Apgar scores of newborn and umbilical cord blood gas values were examined.

RESULTS

Neonatal intensive care need was higher in the general anesthesia (GA) group, Apgar scores were higher in the SA group, but neonatal mortality was similar. The umbilical cord Ph and lactate were lower; PCO2 values were higher in the GA group. Neonatal weight, mother's age, gestational age, and Apgar scores were predictive for neonatal mortality, but anesthesia technique was not.

CONCLUSION

While umbilical cord blood gas values were less affected and the need for neonatal intensive care was lower with SA, we believe that both anesthesia methods can be used safely for mother and neonatal in cesarean anesthesia considering maternal and neonatal morbidity and mortality.

Colloid Preload versus Crystalloid Co-Load in the Setting of Norepinephrine Infusion during Cesarean Section: Time and Type of Administered Fluids Do Not Matter

Background and Goal of Study: Spinal anesthesia for cesarean section is frequently associated with a high incidence of hypotension, which may bring about untoward effects for both the mother and fetus. Recently, norepinephrine has emerged as a promising alternative in maintaining blood pressure in the obstetric setting. Fluid administration is another technique still widely used to prevent maternal hypotension. The optimal fluid strategy to prevent maternal hypotension has not been elucidated yet. It has been recently suggested that the main strategy in the prevention and management of hypotension should be the combination of vasoconstrictive medications and fluid administration. The aim of this randomized study was to compare the incidence of maternal hypotension in parturients receiving either colloid preload or crystalloid co-load in the setting of prophylactic norepinephrine infusion during elective cesarean section under combined spinal-epidural anesthesia. Materials and Methods: After ethics committee approval, 102 parturients with full-term singleton pregnancies were randomly allocated to either 6% hydroxyethyl starch 130/0.4 5 mL/kg before the onset of spinal anesthesia (colloid preload group) or Ringer's lactate solution 10 mL/kg concurrent with the subarachnoid injection (crystalloid co-load group). In both groups, norepinephrine 4 μg/min starting simultaneously with the administration of the subarachnoid solution was also administered. The primary outcome of the study was the incidence of maternal hypotension, defined as systolic arterial pressure (SAP) <80% of baseline. The incidence of severe hypotension (SAP < 80 mmHg), total dose of vasoconstrictive agents administered, as well as the acid-base status and Apgar score of the neonate and any incidence of maternal side effects were also recorded. Results: Data analysis was performed on 100 parturients: 51 in the colloid preload group and 49 in the crystalloid co-load group. No significant differences were demonstrated between the colloid preload group and the crystalloid co-load group in the incidence of hypotension (13.7% vs. 16.3%, p = 0.933) or the incidence of severe hypotension (0% vs. 4%, p = 0.238). The median (range) ephedrine dose was 0 (0-15) mg in the colloid preload group and 0 (0-10) mg in the crystalloid co-load group (p = 0.807). The incidence of bradycardia, reactive hypertension, requirement for modification of vasopressor infusion, time to the first occurrence of hypotension, and maternal hemodynamics did not differ between the two groups. There were no significant differences in other maternal side effects or neonatal outcomes between groups. Conclusions: The incidence of hypotension with a norepinephrine preventive infusion is low and comparable with both colloid preload and crystalloid co-load. Both fluid-loading techniques are appropriate in women undergoing cesarean delivery. It appears that the optimal regimen for prevention of maternal hypotension is a combined strategy of a prophylactic vasopressor such as norepinephrine and fluids.

Preliminary study on fluid bolus administration for prevention of spinal hypotension in dogs undergoing elective cesarean section

Introduction

This study aimed to investigate the effect of fluid bolus administration during epidural anesthesia (coload) in female dogs scheduled for elective cesarean section (CS). Hypotension is one of the most common complications of epidural (EA) and spinal (SA) analgesia, and in the case of cesarean section, it may pose a significant risk for placental perfusion and subsequent fetal vitality and puppy survival.

Methods

Pregnant bitches scheduled for elective CS underwent EA with (treatment group) or without (control group) intravenous fluid bolus administration. The following parameters were measured and compared between both groups: HR, RR, etCO₂, SpO₂, systolic, diastolic and mean arterial blood pressure were measured at three time points (T1: before surgery, T2: after the last puppy removal, and T3: end of surgery) in dams; vitality (Apgar score at 0, 5, and 20 min) and umbilical cord blood parameters (pH, pCO2, HCO3, base excess, lactate and glucose) in newborns.

Results

The results indicated that crystalloid coloading increased maternal systolic, diastolic, and mean blood pressure (treatment vs. control group, 101.46 ± 9.18, 48.01 ± 13.47, and 67.07 ± 13.15 mmHg vs. 80.68 ± 7.29, 36.52 ± 8.75, and 180 52.30 ± 7.77, p < 0.05) with significantly fewer episodes of hypotension. Additionally, puppies in the treatment group received higher scores in the 5-min (7.91 ± 1.67 vs. 6.74 ± 2.20) and 20-min (9.38 ± 0.87 vs. 8.39 ± 2.50) assessments without the favorable effect on umbilical blood gas parameters.

Discussion

Based on the obtained results, it can be stated that crystalloid coload offers an effective option in cases of hypotension during cesarean section, with clear benefits for both mothers and newborns.

Consensus on the Southeast Asian management of hypotension using vasopressors and adjunct modalities during cesarean section under spinal anesthesia

BACKGROUND AND AIMS

This consensus statement presents a comprehensive and evidence-based set of guidelines that modify the general European or US guidelines for hypotension management with vasopressors during cesarean delivery. It is tailored to the Southeast Asian context in terms of local human and medical resources, health system capacity, and local values and preferences.

METHODS AND RESULTS

These guidelines were prepared using a methodological approach. Two principal sources were used to obtain the evidence: scientific evidence and opinion-based evidence. A team of five anesthesia experts from Vietnam, the Philippines, and Thailand came together to define relevant clinical questions; search for literature-based evidence using the MEDLINE, Scopus, Google Scholar, and Cochrane libraries; evaluate existing guidelines; and contextualize recommendations for the Southeast Asian region. Furthermore, a survey was developed and distributed among 183 practitioners in the captioned countries to gather representative opinions of the medical community and identify best practices for the management of hypotension with vasopressors during cesarean section under spinal anesthesia.

CONCLUSIONS

This consensus statement advocates proactive management of maternal hypotension during cesarean section after spinal anesthesia, which can be detrimental for both the mother and fetus, supports the choice of phenylephrine as a first-line vasopressor and offers a perspective on the use of prefilled syringes in the Southeast Asian region, where factors such as healthcare features, availability, patient safety, and cost should be considered.

Effects of colloid preload on the incidence of hypotension in spinal anesthesia for cesarean section: a systematic review and meta-analysis

Background:

Hypotension is a common complication caused by spinal anesthesia (SA), which may have adverse impacts on the condition of the parturient and fetus. Liquid infusion was found to be relatively effective for reducing the incidence of hypotension. However, the question of whether colloid preload can optimize hemodynamic variables in the cesarean section remains controversial. This study aims to determine the effects of colloid preload on the incidence of hypotension induced by SA in elective cesarean section.

Methods:

Related keywords were searched on PubMed, EMBASE, and Cochrane Library from inception dates to May 2020. Studies included were evaluated for eligibility and quality. The primary outcome was the intra-operative incidence of hypotension and severe hypotension. The secondary outcomes included the lowest intra-operative systolic blood pressure, the maximal intra-operative heart rate, the intra-operative needs of ephedrine and phenylephrine, the incidence of maternal nausea and/or vomiting, and neonatal outcomes (umbilical artery pH and Apgar scores). Apart from the above, RevMan 5.3 was used for the data analysis.

Results:

Altogether nine randomized controlled trials were included in the meta-analysis. There were no significant differences in the incidence of intra-operative hypotension, severe hypotension, or neonatal outcomes between the colloid preload group and control group, except for the umbilical artery pH.

Conclusion:

This meta-analysis suggests that colloid preload does not significantly reduce the incidence of hypotension associated with SA in elective cesarean section.

[Comments on the updated German S3 guidelines on intravascular volume therapy in adults]

The German S3 guidelines on intravascular volume therapy in adults were updated in September 2020. Based on updated evidence recommendations for the diagnosis of isotonic dehydration and for fluid therapy with crystalloids and colloids in peri-interventional and intensive care medicine were proposed.

Dexamethasone blunts postspinal hypotension in geriatric patients undergoing orthopedic surgery: a double blind, placebo-controlled study

BACKGROUND

Post-spinal anesthesia (PSA) hypotension in elderly patients is challenging. Correction of PSA hypotension by fluids either colloids or crystalloids or by vasoconstrictors pose the risk of volume overload or compromising cardiac conditions. Dexamethasone is used to treat conditions manifested by decrease of peripheral vascular resistance. The research team was the first to test the hypothesis of its role in preventing or decreasing the incidence of PSA hypotension.

METHODS

One hundred ten patients, aged 60 years or more were recruited to receive a single preoperative dose of dexamethasone 8 mg IVI in 100 ml normal saline (D group) (55 patients) 2 h preoperatively, and 55 patients were given placebo (C group) in a randomized, double-blind trial. Variations in blood pressure and heart rate in addition to the needs of ephedrine and/or atropine following spinal anesthesia (SA) were recorded. SA was achieved using subarachnoid injection of 3 ml hyperbaric bupivacaine 0.5%.

RESULTS

Demographic data and the quality of sensory and motor block were comparable between groups. At 5th, 10th minutes post SA; systolic, diastolic and mean arterial pressures were statistically significant higher in D group. At 20th minutes post SA; the obtained blood pressure readings and heart rate changes didn't show any statistically significance between groups. The need for ephedrine and side effects were statistically significant lower in D group than C group.

CONCLUSION

Post-spinal anesthesia hypotension, nausea, vomiting and shivering in elderly patients were less common after receiving a single preoperative dose of dexamethasone 8 mg IVI than control.

REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT03664037 , Registered 17 September 2018 - Retrospectively registered, http://www.ClinicalTrial.gov.

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.

Control of Spinal Anesthesia-Induced Hypotension in Adults

Spinal anesthesia-induced hypotension (SAIH) occurs frequently, particularly in the elderly and in patients undergoing caesarean section. SAIH is caused by arterial and venous vasodilatation resulting from the sympathetic block along with a paradoxical activation of cardioinhibitory receptors. Bradycardia after spinal anesthesia (SA) must always be treated as a warning sign of an important hemodynamic compromise. Fluid preloading (before initiation of the SA) with colloids such as hydroxyethyl starch (HES) effectively reduces the incidence and severity of arterial hypotension, whereas crystalloid preloading is not indicated. Co-loading with crystalloid or colloid is as equally effective to HES preloading, provided that the speed of administration is adequate (ie, bolus over 5 to 10 minutes). Ephedrine has traditionally been considered the vasoconstrictor of choice, especially for use during SAIH associated with bradycardia. Phenylephrine, a α₁ adrenergic receptor agonist, is increasingly used to treat SAIH and its prophylactic administration (ie, immediately after intrathecal injection of local anesthetics) has been shown to decrease the incidence of arterial hypotension. The role of norepinephrine as a possible alternative to phenylephrine seems promising. Other drugs, such as serotonin receptor antagonists (ondansetron), have been shown to limit the blood pressure drop after SA by inhibiting the Bezold–Jarisch reflex (BJR), but further studies are needed before their widespread use can be recommended.

Effects of isothermic crystalloid coload on maternal hypotension and fetal outcomes during spinal anesthesia for cesarean section: A randomized controlled trial

OBJECTIVE

Spinal anesthesia induced hypotension (SAIH) is a common occurrence during spinal anesthesia for cesarean section resulting in perturbing effects on maternal and fetal outcomes. Previous studies conducted to attenuate SAIH focused on the timing of intravenous fluid infusion and demonstrated the superiority of coload strategy on traditional preload strategy but neither of them focused on the effect of the temperature of crystalloid infused on SAIH and fetal outcomes. The current study aimed to assess the effect of the temperature of the crystalloid infused with coload strategy on the incidence of SAIH and fetal outcomes.

MATERIALS AND METHODS

Seventy-six parturients were enrolled into the study and data of 60 parturients were analyzed. Patients were randomly assigned to receive crystalloid coload at room temperature (Group RT, n = 30) or warmed at 37 °C (Group W, n = 30). The incidence of hypotension, cumulative hypotension episodes, heart rate, core body temperature, ephedrine dose, and fetal outcomes were recorded.

RESULTS

There was no significant difference in the incidence of maternal hypotension, cumulative hypotension episodes, and ephedrine dose (p = 0,625, p = 0,871, p = 0,460 respectively). Umbilical arterial pH and fetal Apgar scores at first and fifth minutes were higher in Group W than in Group RT (p = 0.013, p = 0.006 and p = 0.045 respectively). One fetus in Group RT but none in Group W had umbilical arterial pH lower than seven. Fetal birth weight and rectal temperature measurements were comparable in both groups (p = 0.639 and p = 0.675 respectively). Demographic data, patient characteristics, and surgery data were comparable between groups.

CONCLUSIONS

Isothermic crystalloid coload strategy results in higher umbilical pH values and Apgar scores in parturients scheduled for cesarean section under spinal anesthesia.

Spinal anesthesia-induced hypotension is caused by a decrease in stroke volume in elderly patients

Background

Hypotension is common during spinal anesthesia (SA) and is caused by a decrease in systemic vascular resistance (SVR) and/or cardiac output (CO). The effect of the dose of bupivacaine administered intrathecally on the changes in CO in elderly patients is largely unknown. This study investigated the hemodynamic effect of SA in elderly patients by studying the effect of two different dosages of intrathecal bupivacaine.

Methods

This prospective cohort study included 64 patients aged >65 years scheduled for procedures under SA; the patients received either 15 mg bupivacaine (the medium dose [MD] group) or 10 mg bupivacaine and 5 μg sufentanil (the low dose [LD] group). Blood pressure and CO were monitored throughout the procedure using Nexfin™, a noninvasive continuous monitoring device using a finger cuff.

Results

Thirty-three patients received MD and 31 received LD and there was no mean difference in baseline hemodynamics between the groups. On an average, the CO decreased 11.6% in the MD group and 10.0 % in the LD group. There was no significant change in SVR. Incidence of a clinically relevant decrease in stroke volume (SV) (>15% from baseline) was 67% in the MD and 45% in the LD groups (P<0.05).

Conclusion

CO and blood pressure decreased significantly after the onset of SA in elderly patients. This is mainly caused by a decrease in SV and not by a decrease in SVR. There was no difference in CO and blood pressure change between dosages of 10 or 15 mg bupivacaine.