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Guideline Summary
Guideline Title
Guidelines for the management of vasa previa.
Bibliographic Source(s)
Gagnon R, Morin L, Bly S, Butt K, Cargill YM, Denis N, Hietala-Coyle MA, Lim KI, Ouellet A, Raciot MH, Salem S, Hudon L, Basso M, Bos H, Delisle MF, Farine D, Grabowska K, Menticoglou S, Mundle W, Murphy-Kaulbeck L, Pressey T, Roggensack A. Guidelines for the management of vasa previa. J Obstet Gynaecol Can. 2009 Aug;31(8):748-53. [34 references] PubMed External Web Site Policy
Guideline Status

This is the current release of the guideline.

Scope

Disease/Condition(s)

Vasa previa

Guideline Category
Diagnosis
Evaluation
Management
Risk Assessment
Clinical Specialty
Obstetrics and Gynecology
Pediatrics
Radiology
Intended Users
Advanced Practice Nurses
Physician Assistants
Physicians
Guideline Objective(s)
  • To describe the etiology of vasa previa and the risk factors and associated conditions
  • To identify the various clinical presentations of vasa previa
  • To describe the ultrasound tools used in its diagnosis
  • To describe the management of vasa previa
Target Population

Women with diagnosed vasa previa or who are at risk for vasa previa

Interventions and Practices Considered

Diagnosis/Evaluation

  1. Transvaginal ultrasound
  2. Fetal monitoring
  3. Doppler colour flow mapping
  4. Biochemical test for fetal hemoglobin

Management

  1. Delivery
    • Caesarean section
    • Vaginal (with fetal monitoring)
  2. Corticosteroid therapy
  3. Transfer for delivery to a tertiary facility with facilities for neonatal transfusion/resuscitation
  4. Clear identification of vasa previa diagnosis on patient chart
Major Outcomes Considered
  • Perinatal mortality
  • Short-term neonatal morbidity
  • Long-term infant morbidity
  • Short-term and long-term maternal morbidity and mortality

Methodology

Methods Used to Collect/Select the Evidence
Hand-searches of Published Literature (Secondary Sources)
Searches of Electronic Databases
Searches of Patient Registry Data
Searches of Unpublished Data
Description of Methods Used to Collect/Select the Evidence

Published literature on randomized trials, prospective cohort studies, and selected retrospective cohort studies was retrieved through searches of PubMed or Medline, CINAHL, and the Cochrane Library, using appropriate controlled vocabulary (e.g., selected epidemiological studies comparing delivery by Caesarean section with vaginal delivery; studies comparing outcomes when vasa previa is diagnosed antenatally vs. intrapartum) and key words (e.g., vasa previa). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Searches were updated on a regular basis and incorporated into the guideline to October 1, 2008. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment–related agencies, clinical practice guideline collections, clinical trial registries, and from national and international medical specialty societies.

Number of Source Documents

Not stated

Methods Used to Assess the Quality and Strength of the Evidence
Weighting According to a Rating Scheme (Scheme Given)
Rating Scheme for the Strength of the Evidence

Quality of Evidence Assessment*

I: Evidence obtained from at least one properly randomized controlled trial

II-1: Evidence from well-designed controlled trials without randomization

II-2: Evidence from well-designed cohort (prospective or retrospective) or case-control studies, preferably from more than one centre or research group

II-3: Evidence obtained from comparisons between times or places with or without the intervention. Dramatic results in uncontrolled experiments (such as the results of treatment with penicillin in the 1940s) could also be included in this category

III: Opinions of respected authorities, based on clinical experience, descriptive studies, or reports of expert committees

*Adapted from the Evaluation of Evidence criteria described in the Canadian Task Force on Preventive Health Care

Methods Used to Analyze the Evidence
Systematic Review
Description of the Methods Used to Analyze the Evidence

The evidence collected was reviewed by the Diagnostic Imaging Committee and the Maternal Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and quantified using the evaluation of evidence guidelines developed by the Canadian Task Force on Preventive Health Care.

Methods Used to Formulate the Recommendations
Expert Consensus
Description of Methods Used to Formulate the Recommendations

Not stated

Rating Scheme for the Strength of the Recommendations

Classification of Recommendations

A. There is good evidence to recommend the clinical preventive action

B. There is fair evidence to recommend the clinical preventive action

C. The existing evidence is conflicting and does not allow to make a recommendation for or against use of the clinical preventive action; however, other factors may influence decision-making

D. There is fair evidence to recommend against the clinical preventive action

E. There is good evidence to recommend against the clinical preventive action

L. There is insufficient evidence (in quantity or quality) to make a recommendation; however, other factors may influence decision-making

†Adapted from the Classification of Recommendations criteria described in the Canadian Task Force on Preventive Health Care

Cost Analysis

A formal cost analysis was not performed and published cost analyses were not reviewed.

Method of Guideline Validation
Internal Peer Review
Description of Method of Guideline Validation

This guideline has been prepared by the Diagnostic Imaging Committee and the Maternal Fetal Medicine Committee and approved by Executive and Council of the Society of Obstetricians and Gynaecologists of Canada.

Recommendations

Major Recommendations

The quality of evidence (I–III) and classification of recommendations (A–E, L) are defined at the end of the "Major Recommendations" field.

  1. If the placenta is found to be low lying at the routine second trimester ultrasound examination, further evaluation for placental cord insertion should be performed. (II-2B)
  2. Transvaginal ultrasound may be considered for all women at high risk for vasa previa, including those with low or velamentous insertion of the cord, bilobate or succenturiate placenta, or for those having vaginal bleeding, in order to evaluate the internal cervical os. (II-2B)
  3. If vasa previa is suspected, transvaginal ultrasound colour Doppler may be used to facilitate the diagnosis. Even with the use of transvaginal ultrasound colour Doppler, vasa previa may be missed. (II-2B)
  4. When vasa previa is diagnosed antenatally, an elective Caesarean section should be offered prior to the onset of labour. (II-1A)
  5. In cases of vasa previa, premature delivery is most likely; therefore, consideration should be given to administration of corticosteroids at 28 to 32 weeks to promote fetal lung maturation and to hospitalization at about 30 to 32 weeks. (II-2B)
  6. In a woman with an antenatal diagnosis of vasa previa, when there has been bleeding or premature rupture of membranes, the woman should be offered delivery in a birthing unit with continuous electronic fetal heart rate monitoring and, if time permits, a rapid biochemical test for fetal hemoglobin, to be done as soon as possible; if any of the above tests are abnormal, an urgent Caesarean section should be performed. (III-B)
  7. Women admitted with diagnosed vasa previa should ideally be transferred for delivery in a tertiary facility where a pediatrician and blood for neonatal transfusion are immediately available in case aggressive resuscitation of the neonate is necessary. (II-3B)
  8. Women admitted to a tertiary care unit with a diagnosis of vasa previa should have this diagnosis clearly identified on the chart, and all health care providers should be made aware of the potential need for immediate delivery by Caesarean section if vaginal bleeding occurs. (III-B)

Definitions:

Quality of Evidence Assessment*

I: Evidence obtained from at least one properly randomized controlled trial

II-1: Evidence from well-designed controlled trials without randomization

II-2: Evidence from well-designed cohort (prospective or retrospective) or case-control studies, preferably from more than one centre or research group

II-3: Evidence obtained from comparisons between times or places with or without the intervention. Dramatic results in uncontrolled experiments (such as the results of treatment with penicillin in the 1940s) could also be included in this category

III: Opinions of respected authorities, based on clinical experience, descriptive studies, or reports of expert committees

Classification of Recommendations

A. There is good evidence to recommend the clinical preventive action

B. There is fair evidence to recommend the clinical preventive action

C. The existing evidence is conflicting and does not allow to make a recommendation for or against use of the clinical preventive action; however, other factors may influence decision-making

D. There is fair evidence to recommend against the clinical preventive action

E. There is good evidence to recommend against the clinical preventive action

L. There is insufficient evidence (in quantity or quality) to make a recommendation; however, other factors may influence decision-making

*Adapted from the Evaluation of Evidence criteria described in the Canadian Task Force on Preventive Health Care

†Adapted from the Classification of Recommendations criteria described in the Canadian Task Force on Preventive Health Care

Clinical Algorithm(s)

None provided

Evidence Supporting the Recommendations

Type of Evidence Supporting the Recommendations

The type of supporting evidence is identified and graded for each recommendation (see "Major Recommendations").

Benefits/Harms of Implementing the Guideline Recommendations

Potential Benefits

The benefit expected from this guideline is facilitation of optimal and uniform care for pregnancies complicated by vasa previa.

Potential Harms

Not stated

Qualifying Statements

Qualifying Statements

This document reflects emerging clinical and scientific advances on the date issued and is subject to change. The information should not be construed as dictating an exclusive course of treatment or procedure to be followed. Local institutions can dictate amendments to these opinions. They should be well documented if modified at the local level. None of these contents may be reproduced in any form without prior written permission of the Society of Obstetricians and Gynaecologists of Canada (SOGC).

Implementation of the Guideline

Description of Implementation Strategy

An implementation strategy was not provided.

Implementation Tools
Foreign Language Translations
For information about availability, see the Availability of Companion Documents and Patient Resources fields below.

Institute of Medicine (IOM) National Healthcare Quality Report Categories

IOM Care Need
Getting Better
IOM Domain
Effectiveness
Timeliness

Identifying Information and Availability

Bibliographic Source(s)
Gagnon R, Morin L, Bly S, Butt K, Cargill YM, Denis N, Hietala-Coyle MA, Lim KI, Ouellet A, Raciot MH, Salem S, Hudon L, Basso M, Bos H, Delisle MF, Farine D, Grabowska K, Menticoglou S, Mundle W, Murphy-Kaulbeck L, Pressey T, Roggensack A. Guidelines for the management of vasa previa. J Obstet Gynaecol Can. 2009 Aug;31(8):748-53. [34 references] PubMed External Web Site Policy
Adaptation

Not applicable: The guideline was not adapted from another source.

Date Released
2009 Aug
Guideline Developer(s)
Society of Obstetricians and Gynaecologists of Canada - Medical Specialty Society
Source(s) of Funding

Society of Obstetricians and Gynaecologists of Canada

Guideline Committee

Diagnostic Imaging Committee

Maternal Fetal Medicine Committee

Composition of Group That Authored the Guideline

Principal Author: Robert Gagnon, MD, Montreal QC

Diagnostic Imaging Committee Members: Lucie Morin, MD (Chair), Outremont QC; Stephen Bly, MD, Ottawa ON; Kimberly Butt, MD, Fredericton NB; Yvonne M. Cargill, MD, Ottawa ON; Nanette Denis, ARDMS, CRGS, Saskatoon SK; Robert Gagnon, MD, Montreal QC; Marja Anne Hietala-Coyle, RN, Halifax NS; Kenneth Ian Lim, MD, Vancouver BC; Annie Ouellet, MD, Sherbrooke QC; Maria-Hélène Racicot, MD, Montreal QC; Shia Salem, MD, Toronto ON

Maternal Fetal Medicine Committee Members: Robert Gagnon (Chair), MD, London ON; Lynda Hudon, MD, Montreal QC; Melanie Basso, RN, Vancouver BC; Hayley Bos, MD, London ON; Marie-France Delisle, MD, Vancouver BC; Dan Farine, MD, Toronto ON; Kirsten Grabowska, MD, Vancouver BC; Savas Menticoglou, MD, Winnipeg MB; William Mundle, MD, Windsor ON; Lynn Murphy-Kaulbeck, MD, Allison NB; Annie Ouellet, MD, Sherbrooke QC; Tracy Pressey, MD, Vancouver BC; Anne Roggensack, MD, Calgary AB

Financial Disclosures/Conflicts of Interest

Disclosure statements have been received from all members of the committees.

Guideline Status

This is the current release of the guideline.

Guideline Availability

Electronic copies: Available in Portable Document Format (PDF) from the Society of Obstetricians and Gynaecologists of Canada (SOGC) Web site External Web Site Policy. Also available in French from the SOGC Web site External Web Site Policy.

Print copies: Available from the Society of Obstetricians and Gynaecologists of Canada, La société des obstétriciens et gynécologues du Canada (SOGC) 780 promenade Echo Drive Ottawa, ON K1S 5R7 (Canada); Phone: 1-800-561-2416

Availability of Companion Documents

None available

Patient Resources

None available

NGC Status

This NGC summary was completed by ECRI Institute on April 2, 2010.

Copyright Statement

This NGC summary is based on the original guideline, which is subject to the guideline developer's copyright restrictions.

Disclaimer

NGC Disclaimer

The National Guideline Clearinghouse™ (NGC) does not develop, produce, approve, or endorse the guidelines represented on this site.

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