The Effect of Glycopyrrolate on the Incidence of Hypotension and Vasopressor Requirement During Spinal Anesthesia for Cesarean Delivery

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.

Effect of glycopyrrolate on vasopressor requirements for non-elective cesarean section under spinal anesthesia: a randomized, double-blind, placebo-controlled trial

Background

The study aimed to investigate whether prophylactic use of glycopyrrolate decreases the vasopressor requirements to prevent hypotension following spinal anesthesia during non-elective cesarean section.

Method

In this double-blind randomized clinical trial, 258 patients undergoing non-elective cesarean section were randomly assigned (1:1) to receive intravenous 0.2 mg glycopyrrolate or normal saline (placebo) before spinal anesthesia. The primary outcome was phenylephrine equivalent needed intraoperatively. Secondary outcomes included incidences of maternal hypotension, reactive hypertension, bradycardia, need for atropine, tachycardia, intraoperative nausea/vomiting, shivering, pruritus, dry mouth, dizziness; neonatal APGAR score at 1 min and 5 min, neonatal resuscitation needed, NICU admission and neonatal death.

Results

Three patients withdrew from the study due to failed spinal anesthesia. 128 patients in the glycopyrrolate group and 127 patients in the placebo group were analyzed. The mean phenylephrine equivalent needed was 1108.96 μg in the glycopyrrolate group and 1103.64 μg in the placebo group (mean difference, 5.32 μg [95% CI − 67.97 to 78.62]; P = 0.88). Hypotension occurred in 38 patients (30%) in the glycopyrrolate group as compared with 49 patients (39%) in the placebo group (P = 0.13). Tachycardia was reported in 70% of the participants in the glycopyrrolate group and 57% of those in the placebo group (P = 0.04). No statistically significant difference was noted in hypotensive episodes > 1, reactive hypertension, bradycardia, need for atropine, nausea, vomiting, shivering, and dry mouth between the two groups. Neonatal outcomes were similar in the two groups.

Conclusion

Prophylactic use of glycopyrrolate does not decrease the requirements of vasopressor to prevent hypotension in non-elective cesarean section under spinal anesthesia.

Trial registration

Registration number: NCT04401345. Date of registration: 26/05/2020. Website: https://clinicaltrials.gov

Spinal hypotension in obstetrics: Context-sensitive prevention and management

Spinal hypotension during caesarean section remains a common complication, with important attendant maternal and fetal adverse outcomes. Research elucidating the mechanisms of spinal hypotension has led to the development and refinement of effective management strategies, with a particular emphasis on prophylactic vasopressor administration. This has proved effective in well-resourced settings, with maternal comfort and the elimination of nausea now considered the primary aim of treatment. In resource-limited settings, sophisticated strategies are not feasible due to insufficient equipment, staff, and expertise. Therefore, in these areas spinal hypotension remains an important cause of maternal and fetal morbidity and mortality. Translational, context-sensitive research in resource-limited settings has shown promise in implementing pragmatic strategies based on research from resource-rich environments. We review the current best practice for the prevention and treatment of spinal hypotension, with a special emphasis on effective strategies in resource-limited settings. We further suggest a research agenda to address the knowledge gap in specific contexts.

[Hypotension induced by spinal anesthesia during cesarean section : Current treatment concepts]

Arterial hypotension during cesarean delivery under spinal anesthesia can cause maternal and fetal adverse effects. Therefore, current guidelines recommend the continuous and preferably prophylactic use of vasopressors, emphasizing the use of alpha-agonists, such as phenylephrine. Besides a left lateral uterine displacement either an intravenous colloid preloading or a crystalloid co-loading is recommended. The blood pressure goal is to maintain a systolic arterial blood pressure of at least 90% of the initial baseline value and to avoid a drop to less than 80% of this baseline. To achieve this goal a prophylactic continuous phenylephrine infusion with an adjustable flow rate is recommended. It is advised to start with an initial dose of 25-50 µg/min, initiated immediately following the intrathecal injection of the local anesthetic and titrated according to the vital parameters. Parturients with cardiac diseases should be preoperatively evaluated following individual hemodynamic goals.

Effect of prophylactic combination of glycopyrrolate, ondansetron, and ephedrine upon hypotension during obstetric spinal anaesthesia–A randomised controlled trial

Background and Aims:

Various pharmacological and non-pharmacological strategies have been employed to minimise hypotension during obstetric spinal anaesthesia. We compared a prophylactic combination of glycopyrrolate, ondansetron, and ephedrine in terms of total vasopressor consumption, with standard treatment in this randomised controlled trial.

Methods:

One hundred patients undergoing elective caeserean sections were randomly divided into two groups of 50 each, the study group received prophylactic ondansetron and glycopyrrolate boluses followed by an infusion of ephedrine, while the control group received ephedrine boluses as required. The total ephedrine consumption (primary objective), incidence and degree of hypotension, heart rate variations, and neonatal APGAR scores (secondary objectives) were analysed.

Results:

The median ephedrine requirement was lesser in the study group compared to the control group [13.2 mg (10--15.75) vs. 27.7 mg (12--24)], with a P value of 0.02. Fewer participants experienced hypotension in the study group before baby delivery compared to the control group (12 vs. 36, P = 0.004). Heart rate was higher in the study group. No significant differences were observed in neonatal APGAR scores and incidence of adverse events.

Conclusion:

A combination of glycopyrrolate, ondansetron, and ephedrine might offer better haemodynamic stability and reduce vasopressor consumption in obstetric patients undergoing spinal anaesthesia as opposed to standard treatment.

Prevention of hypotension after spinal anaesthesia for caesarean section: a systematic review and network meta-analysis of randomised controlled trials

Spinal anaesthesia for caesarean section commonly causes maternal hypotension. This systematic review and network meta-analysis compared methods to prevent hypotension in women receiving spinal anaesthesia for caesarean section. We selected randomised controlled trials that compared an intervention to prevent hypotension with another intervention or inactive control by searching MEDLINE and Embase, Web of Science to December 2018. There was no language restriction. Two reviewers extracted data on trial characteristics, methods and outcomes. We assessed risk of bias for individual trials (Cochrane tool) and quality of evidence (GRADE checklist). We assessed 109 trials (8561 women) and 12 different methods that resulted in 30 direct comparisons. Methods ranked by OR (95%CI) from most effective to least effective were: metaraminol 0.11 (0.04-0.26); norepinephrine 0.13 (0.06-0.28); phenylephrine 0.18 (0.11-0.29); leg compression 0.25 (0.14-0.43); ephedrine 0.28 (0.18-0.43); colloid given before induction of anaesthesia 0.38 (0.24-0.61); angiotensin 2, 0.12 (0.02-0.75); colloid given after induction of anaesthesia 0.52 (0.30-0.90); mephentermine 0.09 (0.01-1.30); crystalloid given after induction of anaesthesia 0.78 (0.46-1.31); and crystalloid given before induction of anaesthesia 1.16 (0.76-1.79). Phenylephrine caused maternal bradycardia compared with control, OR (95%CI) 0.23 (0.07-0.79). Ephedrine lowered umbilical artery pH more than phenylephrine, standardised mean difference (95%CI) 0.78 (0.47-1.49). We conclude that vasopressors should be given to healthy women to prevent hypotension during caesarean section with spinal anaesthesia.