Condition category
Pregnancy and Childbirth
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Lay summary under review 3

Trial website

Contact information



Primary contact

Dr Augusto Navarro Hernando


Contact details

Seccion de Anestesia
Hospital Universitario Miguel Servet
Paseo Isabel La Católica 1-3

Additional identifiers

EudraCT number number

Protocol/serial number

EC 10/060

Study information

Scientific title

Prediction of hypotension caused by spinal block in caesarean section by the analysis of the activity of the autonomic nervous system, and the effects of pharmacological prophylaxis of hypotension on foetal well-being: a double-blinded prospective clinical trial


Study hypothesis

Prophylaxis of hypotension with phenylephrine has negative effects on the pH of umbilical cord in not prone to develop hypotension pregnants, which offsets the potential positive impact of prevention on the pH of cord of patients prone to develop it. The hemodynamic stress of the decubitus supine position (supine stress test) can induce additional changes in the autonomic nervous system (ANS), which would improve the ability of Heart rate variability (HRV) analysis of prediction of the hypotension. The simultaneous study of different indicators and modes of analysis of the activity of the ANS and its variations between bed rest and supine stress will make it possible to identify the component of the spectrum of frequency variability and the indicator of better ability to prediction of the hypotension.

Ethics approval

The Clinical Research Ethics Committee of Aragon [Comité Ético de Investigación Clínica de Aragón (CEICA)], 27 July 2011 ref: C.I.EC10/060

Study design

Prospective clinical double blinded trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Caesarean section and hypotension after spinal block


The interventions included in the clinical trial will be the following ones:
For the anaesthetic technique and management, the interventions included will be crystalloid preload with Ringer Lactate 1000 ml, puncture in site position in L3-4 or L2-3 with Withacre G25 or G27 needle, block with Bupivacaine 0.5% hyperbaric (10 mg in height <155cm, 11mg in height 155-165 cm, 12 mg in >165 cm) with 0.15 mg of morphic chlorure conservant free addition. Supine position with 45º left tilt. Maintenance of the venous with a Ringer Lactated infusion at 15 ml/kr-1•min-1.

If the patient is assigned to treatment group, they will receive a parallel infusion of phenylephrine through an infusion bomb at 1 ml•kg-1•min-1 for the hypotension prophylaxis, and if the patient is assigned to control group will only receive a placebo infusion. The hypotension treatment will consist on an ephedrine intravenous bolus correction in both groups if necessary, with an initial 5 mg dose, and adding additional bolus if the hypotension does not stop.

Intervention type



Not Applicable

Drug names

Primary outcome measures

1. The first part of the trial will study different indicators of the ANS (autonomic nervous system) activity and their arterial hypotension prediction capacity related to the caesarean intervention spinal anaesthesia
2. The ANS activity will be measured through HRV, PRV and Pulse Transit Time Variability (PTTV) and a digital register of the ECG curve

Secondary outcome measures

1. The second part of the trial is the study of the hypotension prophylaxis with phenylephrine effect in the foetal well-being. This will be measured through an arterial and venous blood sample from the umbilical cord to determinate gases, acid-base balance and lactic acid
2. Other measurements will be done, a register and evaluation of the maternal total antioxidant system (TAS), TAM, TAD, FC and oxygen saturation (Sat O2) at baseline and at 5 and 20 minutes of the epinephrine bolus infusion, the number of epinephrine bolus, dose and administration time and the times of epinephrine bolus initiation, uterine incision and foetal extraction
3. Nausea and vomiting (adverse effects)

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Pregnant women scheduled for caesarean section in first turn on the surgical part
2. Have given her informed consent to participate in the trial asked in the preanaesthetic consultation

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Presence of uterine dynamics
2. Multiple pregnancies
3. Maternal pathology related or not with the gestation
4. Suspicion of foetal pathology

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Seccion de Anestesia

Sponsor information


Aragon Institute of Health Sciences [Instituto Aragonés de Ciencias de la Salud] (Spain)

Sponsor details

Avenida Gómez Laguna 25
Planta 11

Sponsor type

Research organisation



Funder type

Research organisation

Funder name

Aragon Institute of Health Sciences [Instituto Aragonés de Ciencias de la Salud] (Spain)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes