Hypotension
Conditions
Keywords
spinal anesthesia, cesarean section
Brief summary
The purpose of this study is to compare two methods for preventing low blood pressure associated with spinal anesthesia during Cesarean sections.
Detailed description
Many women experience low blood pressure after spinal anesthesia for Cesarean section. This low blood pressure may result in nausea, vomiting dizziness and impairment of uterine blood flow.The purpose of this study is to compare two methods for preventing low blood pressure associated with spinal anesthesia during Cesarean sections. In both methods, we will attempt to prevent low blood pressure using phenylephrine infusion that has been shown to be effective in recent research. In addition to receiving phenylephrine one group of patients will receive standard salt solution (Ringer's lactate solution), while the other group will receive a different, intravenous fluid called hydroxyethylstarch.
Interventions
OTHERColloid administration
The patients received 0.5 L colloid solution (hydroxyethylstarch 6%) or 1.5 L Ringer lactate prior to spinal anesthesia for cesarean section.
OTHERCrystalloid administration
The patients received 1.5 L Ringer lactate prior to spinal anesthesia for cesarean section.
A phenylephrine infusion will be started immediately after performing the spinal anesthesia and continued until time of uterine incision.
Sponsors
Milton S. Hershey Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 35 Years
Healthy volunteers
No
Inclusion criteria
* American Society of Anesthesiologists (ASA) physical status I and II * Elective cesarean section * Weight 50-120 kg, Height 150-180 cm * Normal singleton pregnancy * Beyond 36 weeks gestation * No known fetal abnormalities * Ages 18-35
Exclusion criteria
* Contraindications to spinal anesthesia * Multiple gestation, placenta previa, accreta * Pregnancy induced hypertension or preeclampsia * Diabetes mellitus, cardiovascular diseases * Coagulopathy * Spinal cord abnormalities, spinal surgery, or preexisting neurological dysfunction * Baseline HR \<65 * Failed spinal anesthesia/inadequate sensory block for surgery * History of abnormal bleeding * History of adverse reactions to hydroxyethylstarch
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Incidence of Maternal Hypotension | participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Dosage of Phenylephrine Used | participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby | — |
| Incidence of Maternal Bradycardia | participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby | — |
| Fetal Cord Blood pH | delivery of the baby | — |
| APGAR Scores | Apgar scores were assessed at 1 amd 5 min after delivery of the baby | The Apgar score is determined by evaluating the newborn baby on five simple criteria on a scale from zero to two, then summing up the five values thus obtained. The resulting Apgar score ranges from zero to 10 with higher scores being better than lower scores. The five criteria are summarized using words chosen to form an acronym (Appearance, Pulse, Grimace, Activity, Respiration). |
| Incidence of Maternal Nausea and Vomiting | participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby | — |
Countries
United States
Participant flow
Recruitment details
We applied for an IRB approval for 90 patients. The power analysis indicated that a minimum of 37 subjects for each group was needed. To allow for potential dropouts, we applied for 45 patient in each group. (total of 9O patients)
Participants by arm
| Arm | Count |
|---|---|
| Colloid, Then Phenylephrine Infusion colloid administration; with 0.5 L Hydroxyethylstarch solution at a rate of 17 ml/min and completed over 30 min.A phenylephrine infusion will be started immediately after performing the spinal anesthesia and continued until time of uterine incision. | 41 |
| Crystalloid, Then Phenylephrine Infusion Crystalloid administration; 1.5 L Ringer's lactate infusion at a rate of 50 ml/min and completed over 30 min. A phenylephrine infusion will be started immediately after performing the spinal anesthesia and continued until time of uterine incision. | 41 |
| Total | 82 |
Baseline characteristics
| Characteristic | Crystalloid, Then Phenylephrine Infusion | Colloid, Then Phenylephrine Infusion | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 41 Participants | 41 Participants | 82 Participants |
| Age, Continuous | 28.3 years STANDARD_DEVIATION 5.9 | 25.9 years STANDARD_DEVIATION 5.1 | 26.6 years STANDARD_DEVIATION 5.3 |
| Region of Enrollment United States | 41 participants | 41 participants | 82 participants |
| Sex: Female, Male Female | 41 Participants | 41 Participants | 82 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 41 | 0 / 41 |
| serious Total, serious adverse events | 0 / 41 | 0 / 41 |
Outcome results
Primary
Incidence of Maternal Hypotension
Time frame: participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Colloid, Then Phenylephrine Infusion | Incidence of Maternal Hypotension | 10.8 percentage of participants |
| Crystalloid, Then Phenylephrine Infusion | Incidence of Maternal Hypotension | 27 percentage of participants |
Secondary
APGAR Scores
The Apgar score is determined by evaluating the newborn baby on five simple criteria on a scale from zero to two, then summing up the five values thus obtained. The resulting Apgar score ranges from zero to 10 with higher scores being better than lower scores. The five criteria are summarized using words chosen to form an acronym (Appearance, Pulse, Grimace, Activity, Respiration).
Time frame: Apgar scores were assessed at 1 amd 5 min after delivery of the baby
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Colloid, Then Phenylephrine Infusion | APGAR Scores | 9 units on a scale |
| Crystalloid, Then Phenylephrine Infusion | APGAR Scores | 9 units on a scale |
Secondary
Dosage of Phenylephrine Used
Time frame: participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Colloid, Then Phenylephrine Infusion | Dosage of Phenylephrine Used | 1077 mcg of phenylephrine | Standard Deviation 541 |
| Crystalloid, Then Phenylephrine Infusion | Dosage of Phenylephrine Used | 1477 mcg of phenylephrine | Standard Deviation 591 |
Secondary
Fetal Cord Blood pH
Time frame: delivery of the baby
Population: Physician policy changes resulted in blood gas values not being ordered and thus data was not available for the outcome measure.
Secondary
Incidence of Maternal Bradycardia
Time frame: participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Colloid, Then Phenylephrine Infusion | Incidence of Maternal Bradycardia | 35.1 percentage of participants |
| Crystalloid, Then Phenylephrine Infusion | Incidence of Maternal Bradycardia | 45.8 percentage of participants |
Secondary
Incidence of Maternal Nausea and Vomiting
Time frame: participants were assessed for an average of 20 min, after performing the spinal anesthetic till the delivery of the baby
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Colloid, Then Phenylephrine Infusion | Incidence of Maternal Nausea and Vomiting | 16.2 percentage of participants |
| Crystalloid, Then Phenylephrine Infusion | Incidence of Maternal Nausea and Vomiting | 18.9 percentage of participants |