Predicting Hypotension Related to Spinal Anesthesia

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
University of British Columbia
ClinicalTrials.gov Identifier:
NCT01279889
First received: January 18, 2011
Last updated: February 10, 2012
Last verified: February 2012
  Purpose

This study aims to identify women at risk of low blood pressure (hypotension) after the usual cesarean anesthetic - a spinal anesthetic. Hypotension may be caused by dehydration. We believe we can predict who will get hypotension by using two anesthesia monitors together with a passive leg raise (PLR) (legs elevated after a period spent reclining). The PLR will cause a shift of blood from the legs to the heart, and the monitors will detect the heart's response to tell if a subject is dehydrated. We want to see if these dehydration tests can also predict hypotension after a spinal anesthetic.


Condition
Hypotension

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Predicting Hypotension Resistant to Phenylephrine (PE) Infusion in Elective Cesarean Delivery (CD)

Resource links provided by NLM:


Further study details as provided by University of British Columbia:

Primary Outcome Measures:
  • Passive leg raise related cardiac output change and correlation with presence of phenylephrine infusion resistant hypotension [ Time Frame: One hour prior to scheduled cesarean delivery ] [ Designated as safety issue: No ]
  • Passive leg raise related plethysmography variability index change and correlation with presence of phenylephrine infusion resistant hypotension [ Time Frame: One hour prior to scheduled cesarean delivery ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Baseline plethysmography variability index, plethysmography index and systemic vascular resistance values and correlation with presence of phenylephrine infusion resistant hypotension [ Time Frame: From administration of spinal anesthetic to delivery of infant ] [ Designated as safety issue: No ]
  • Passive leg raise related plethysmography variability index and cardiac output change and correlation with severe phenylephrine resistant hypotension [ Time Frame: One hour prior to scheduled cesarean delivery ] [ Designated as safety issue: No ]
    Defined as requirement of 3 or more rescue bolus doses of vasopressor/anticholinergic according to intervention protocol

  • Passive leg raise related plethysmography variability index and cardiac output change and correlation with hypotension associated with bradycardia [ Time Frame: One hour prior to scheduled cesarean delivery ] [ Designated as safety issue: No ]
  • Presence of phenylephrine infusion associated side effects [ Time Frame: From administration of spinal anesthetic to delivery of infant ] [ Designated as safety issue: No ]
    Hypertension or normotensive bradycardia associated with phenylephrine infusion use

  • Presence of recurrent (3 or more) episodes of phenylephrine infusion associated side effects [ Time Frame: From administration of spinal anesthetic to delivery of infant ] [ Designated as safety issue: Yes ]
  • Maternal cardiac output and systemic vascular resistance changes following spinal anesthesia [ Time Frame: From administration of spinal anesthesia to delivery of infant ] [ Designated as safety issue: No ]
  • Umbilical cord gases [ Time Frame: At delivery of infant ] [ Designated as safety issue: No ]
  • Apgar scores at 1 and 5 minutes [ Time Frame: At delivery of infant ] [ Designated as safety issue: No ]

Enrollment: 47
Study Start Date: January 2011
Study Completion Date: July 2011
Primary Completion Date: July 2011 (Final data collection date for primary outcome measure)
Groups/Cohorts
Cesarean Delivery
Healthy pregnant women having an elective cesarean delivery

  Show Detailed Description

  Eligibility

Ages Eligible for Study:   19 Years and older
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population

Healthy women who are admitted to the hospital for a scheduled elective cesarean delivery

Criteria

Inclusion Criteria:

  • Height less than 150cm or greater than 180cm
  • Body Mass Index (BMI) greater than 40kg/m2: obesity makes accurate non-invasive blood pressure (BP) measurement difficult. It may also affect speed of onset and height of subarachnoid block due to increased epidural venous plexus engorgement and thecal sac compression resulting in more marked hypotension.
  • Pregnancy induced hypertension (BP after 20wk greater than 140/90 with proteinuria)
  • High risk of hemorrhage - where fluid volume expansion is planned prior to delivery (e.g. placenta previa, placenta accreta)

Exclusion Criteria:

  • Starting BP is less than 100 systolic: as the lower limit for intervention defined in this study is 90sys which will likely be within the error of the BP measurement device
  • There is a prolonged (more than 2 hour) wait between testing and spinal insertion: as patients may become more dehydrated affecting hypotension rates
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01279889

Locations
Canada, British Columbia
British Columbia Women's Hospital
Vancouver, British Columbia, Canada, V6H 3N1
Sponsors and Collaborators
University of British Columbia
Investigators
Principal Investigator: Vit Gunka, MD University of British Columbia
  More Information

No publications provided

Responsible Party: University of British Columbia
ClinicalTrials.gov Identifier: NCT01279889     History of Changes
Other Study ID Numbers: H10-03231
Study First Received: January 18, 2011
Last Updated: February 10, 2012
Health Authority: Canada: Health Canada

Keywords provided by University of British Columbia:
hypotension
cesarean delivery
cardiac output
blood pressure
plethysmography variability index

Additional relevant MeSH terms:
Hypotension
Vascular Diseases
Cardiovascular Diseases

ClinicalTrials.gov processed this record on July 22, 2014