Vasopressors for the Treatment and Prophylaxis of Spinal Induced Hypotension during Caesarean Section

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.

Benefits and Risks of Medications Used in the Management of Hypotension: A Review

This comprehensive literature review addresses the scarcity and limited study of hypotension treatments compared to abundant antihypertensive drugs. Hypotension, categorized as absolute, relative, or orthostatic, has diverse causes. This review explores various treatments, including drugs affecting the sympathetic nervous system, such as midodrine, dihydroergotamine, and ergotamine, which have shown efficacy in managing hypotension. Dopamine agonists/antagonists and other drugs such as ephedrine, norepinephrine, and fludrocortisone are also discussed, each with distinct mechanisms and applications. Additionally, adjunctive agents such as non-steroidal anti-inflammatory agents, caffeine, and monoamine oxidase inhibitors are reviewed for their effects on blood pressure. This review underscores the importance of understanding the efficacy and safety profiles of hypotension treatments to guide healthcare professionals in optimal drug selection and management, emphasizing the need for further research and comparative studies for evidence-based guidelines.

Effect of preoperative oral rehydration before cesarean section on ultrasound assessment of gastric volume and intraoperative hemodynamic changes: a randomized controlled trial

BACKGROUND

Cesarean section often requires an urgent transfusion load due to decreased blood pressure after spinal anesthesia. This prospective randomized study aimed to investigate whether a preoperative oral rehydration solution (ORS) stabilized perioperative circulatory dynamics.

METHODS

Sixty-three parturients scheduled for cesarean section under combined spinal epidural anesthesia (CSEA) were randomly allocated to one of three groups: Group O received 500 mL ORS before bedtime and 500 mL 2 h before CSEA; Group M received mineral water instead of ORS; and Group C had no fluid intake (controls). After entering the operating room, stomach size was measured using ultrasound. Blood samples were obtained, and CSEA was induced. Vasopressors were administered when systolic blood pressure was < 90 mmHg or decreased by > 20%. As a vasopressor, phenylephrine (0.1 mg) was administered at ≥ 60 beats/min heart rate or ephedrine (5 mg) at < 60 beats/min heart rate. The primary outcome was the total number of vasopressor boluses administered. Secondary outcomes were the cross-sectional area of the stomach antrum, maternal plasma glucose levels, serum sodium levels, total intravenous fluid, bleeding volume, urine volume, operative time, and cord blood gas values after delivery.

RESULTS

The total number of vasopressor boluses was lower in Group O than in Group C (P < 0.05). Group O had lower total dose of phenylephrine than Group C (P < 0.05). There were no significant differences between Group M and other groups. No differences were detected regarding secondary outcomes.

CONCLUSIONS

In women scheduled for cesarean section, preoperative ORS stabilized perioperative circulatory dynamics. Neither ORS nor mineral water consumption increased the stomach content volume.

TRIAL REGISTRATION

This trial is registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN000019825: Date of registration 17/11/2015).

Effect of Crystalloid or Colloid Fluid Loading and Vasopressor Pre-Treatment on the Timing of Hypotension in Cesarean Section with Subarachnoid Block

BACKGROUND: Cesarean section (C-section) is the most frequently performed surgery in obstetrics, generally using subarachnoid block (SAB) or epidural block for anesthesia. The previous studies have shown the effectiveness of fluid loading and vasopressor pretreatment in preventing maternal hypotension (decreased blood pressure), the most common side effect of SAB. However, the timing of hypotension in response to these treatments has not been analyzed. AIM: This study therefore aimed to compare the effects of crystalloid or colloid fluid loading and vasopressor pre-treatment on the timing of hypotension in cases of C-section under SAB anesthesia. METHODS: The study was a single-blind randomized controlled clinical trial with three treatment groups: Group I, 10 mL/kgBW crystalloid solution (Ringer’s lactate) loading 10 min before SAB; Group II, 5 mL/kgBW colloid fluid (gelatin) loading 10 min before SAB; and Group III, pretreatment with 0.1 mg/kgBW vasopressor (ephedrine) intravenous bolus just before SAB. RESULTS: Significant differences in mean blood pressure between groups were observed between the second and 8th min (p < 0.05). Hypotension was observed in the crystalloid group within the first 5 min, while average blood pressure was relatively stable all groups after the first 10 min. In addition, hypotension occurred more frequently in the crystalloid group (nine subjects, 45%), compared with the colloid and vasopressor groups (two subjects per group, 10%; p < 0.05). CONCLUSION: Hypotension occurred more rapidly and more frequently when crystalloid loading was utilized, compared with colloid loading or vasopressor pretreatment. Administration of colloid fluid loading and vasopressor pretreatment has been shown to prevent hypotension in SAB anesthesia.

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.