Adverse Effect
Conditions
Keywords
Norepinephrine, Postspinal anesthesia hypotension, Coload, Cesarean section
Brief summary
The purpose of this study is to investigate the effect of different crystalloid coload volumes on the 90% effective dose of prophylactic norepinephrine infusions for preventing postspinal anesthesia hypotension during cesarean section.
Detailed description
Post-spinal anesthesia hypotension is a frequent complication during spinal anesthesia for cesarean section. The incidence of post-spinal anesthesia hypotension is as high as 62.1-89.7% if prophylactic measures are not taken. Coload has been highly demonstrated for prevention and/or treatment of post-spinal anesthesia hypotension. In addition, there's some evidence that prophylactic infusion of norepinephrine could effectively reduce the incidence of post-spinal anesthesia hypotension in parturients undergoing cesarean section. The purpose of this study is to investigate the effect of different crystalloid coload volumes on the 90% effective dose of norepinephrine infusion prophylaxis for hypotension during spinal anesthesia for cesarean section.
Interventions
DRUGCrystalloid - 0 ml/kg
No fluid coload was given. An initial infusion dose of prophylactic norepinephrine (0.025 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.005 ug/kg/min of prophylactic norepinephrine according to the responses of previous patients according to the up-down sequential allocation.
DRUGCrystalloid - 5 ml/kg
5 ml/kg crystalloid coload combined with an initial infusion dose of prophylactic norepinephrine (0.025 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.005 ug/kg/min of prophylactic norepinephrine according to the responses of previous patients according to the up-down sequential allocation.
DRUGCrystalloid - 10 ml/kg
10 ml/kg crystalloid coload combined with an initial infusion dose of prophylactic norepinephrine (0.025 ug/kg/min) simultaneous with spinal anesthesia. The dose administered to subsequent patients varied by increments or decrements of 0.005 ug/kg/min of prophylactic norepinephrine according to the responses of previous patients according to the up-down sequential allocation.
Sponsors
General Hospital of Ningxia Medical University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
* 18-45 years * Primipara or multipara * Singleton pregnancy ≥37 weeks * American Society of Anesthesiologists physical status classification I to II * Scheduled for cesarean section under spinal anesthesia
Exclusion criteria
* Body height \< 150 cm * Body weight \> 100 kg or body mass index (BMI) ≥ 40 kg/m2 * Eclampsia or chronic hypertension or baseline blood pressure ≥180 mmHg * Hemoglobin \< 7g/dl * Fetal distress, or known fetal developmental anomaly
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| ED50 and ED90 | 1-15 minutes after spinal anesthesia | The dose of prophylactic norepinephrine that would be effective in preventing postspinal anesthesia hypotension in 50% (effective dose, ED 50) and 90% (ED90) of patients |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The incidence of severe post-spinal anesthesia hypotension | 1-15 minutes after spinal anesthesia | Systolic blood pressure (SBP) \< 60% of the baseline |
| The incidence of bradycardia | 1-15 minutes after spinal anesthesia | Heart rate \< 60 beats/min |
| The incidence of nausea and vomiting | 1-15 minutes after spinal anesthesia | Presence of nausea and vomiting in patients after spinal anesthesia |
| The incidence of hypertension | 1-15 minutes after spinal anesthesia | Systolic blood pressure (SBP) \>120% of the baseline |
| The incidence of post-spinal anesthesia hypotension | 1-15 minutes after spinal anesthesia | Systolic blood pressure (SBP) \< 80% of the baseline |
| 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 minute after delivery | A= Appearance P=Pulse G=Grimace A=Attitude R=Respiration |
| pH | Immediately after delivery | From umbilical arterial blood gases |
Countries
China
Outcome results
None listed