Hemodynamic Instability
Conditions
Keywords
Norepinephrine, Phenylephrine, Hemodynamic effects, Preeclampsia, Cesarean section
Brief summary
The purpose of this study is to investigate the maternal cardiac output response to prophylactic norepinephrine and phenylephrine infusion for postspinal anesthesia hypotension in parturients with preeclampsia undergoing cesarean section.
Detailed description
Preeclampsia, which affects 5% to 7% of parturients, is a significant cause of maternal and neonatal morbidity and mortality. Because of constricted myometrial spiral arteries with exaggerated vasomotor responsiveness, though blood pressure in parturients with preeclampsia are apparently higher than healthy parturients, placental hypoperfusion is more common. Spinal anesthesia is still the preferred mode of anesthesia in parturients with preeclampsia for cesarean section. In preeclampsia parturients, spinal anesthesia improve intervillous blood flow (provided that hypotension is avoided) which contribute to increase placental perfusion. Even so, 17-26% parturients with preeclampsia experienced postspinal anesthesia hypotension due to the extensive sympathetic block that occurred with spinal anesthesia. As a potential substitute drug for phenylephrine and ephedrine, norepinephrine has gained traction for use in parturients undergoing cesarean section. However, hemodynamic effects of the prophylactic norepinephrine infusion is still unknown. The purpose of this study is to investigate the maternal cardiac output response to prophylactic norepinephrine and phenylephrine infusion for postspinal anesthesia hypotension in parturients with preeclampsia undergoing cesarean section.
Interventions
DRUGNorepinephrine
A maintenance dose of norepinephrine (0.05 μg/kg/min) infusion simultaneous with subarachnoid block
DRUGPhenylephrine
A maintenance dose of phenylephrine (0.625 μg/kg/min) infusion simultaneous with subarachnoid block
Sponsors
General Hospital of Ningxia Medical University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Caregiver)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
* 18-45 years * Primipara or multipara * Singleton pregnancy ≥32 weeks * American Society of Anesthesiologists physical status classification II to III * Scheduled for cesarean section under spinal anesthesia
Exclusion criteria
* Baseline blood pressure ≥180 mmHg * Body height \< 150 cm * Body weight \> 100 kg or body mass index (BMI) ≥ 40 kg/m2 * Eclampsia or chronic hypertension * Hemoglobin \< 7g/dl * Fetal distress, or known fetal developmental anomaly
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Cardiac output (CO) | 1-30 minutes after spinal anesthesia | Evaluated by the VIGILCO monitoring system |
| Stroke volume (SV) | 1-30 minutes after spinal anesthesia | Evaluated by the VIGILCO monitoring system |
| Systemic vascular resistance (SVR) | 1-30 minutes after spinal anesthesia | Evaluated by the VIGILCO monitoring system |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The incidence of severe post-spinal anesthesia hypotension. | 1-30 minutes after spinal anesthesia. | Systolic blood pressure (SBP) \< 60% of the baseline |
| The incidence of hypertension. | 1-30 minutes after spinal anesthesia | Systolic blood pressure (SBP) \>120% of the baseline. |
| The incidence of bradycardia. | 1-30 minutes after spinal anesthesia | Heart rate \< 60 beats/min. |
| The incidence of nausea and vomiting. | 1-30 minutes after spinal anesthesia | Presence of nausea and vomiting in patients after spinal anesthesia |
| Overall stability of systolic blood pressure control versus baseline | 1-30 minutes after spinal anesthesia | Evaluated by performance error (PE) |
| Partial pressure of oxygen (PO2) | Immediately after delivery | From umbilical arterial blood gases. |
| Base excess (BE) | Immediately after delivery | From umbilical arterial blood gases. |
| APGAR score | 1 min after delivery | A= Appearance P=Pulse G=Grimace A=Attitude R=Respiration |
| pH | Immediately after delivery | From umbilical arterial blood gases. |
| Overall stability of heart rate control versus baseline | 1-30 minutes after spinal anesthesia | Evaluated by performance error (PE) |
| The incidence of post-spinal anesthesia hypotension | 1-30 minutes after spinal anesthesia. | Systolic blood pressure (SBP) \< 80% of the baseline |
Countries
China
Contacts
Primary ContactXinli Ni, Dr.
Backup ContactYi Chen, M.D.
Outcome results
None listed