Slow and Deep Breathing to Lower Blood Pressure in Women With Pregnancy-induced Hypertension

Pregnancy-Induced Hypertension Clinical Trial

Official title:

Effects of Slow and Deep Breathing on Reducing Obstetric Intervention in Women With Pregnancy-induced Hypertension:A Feasibility Study

Clinical Trial Details — Status: Suspended

Administrative data

• NCT number: NCT04059822
• Other study ID #: 251062
• Status: Suspended
• Phase: N/A
• Start date: January 14, 2020
• Est. completion date: December 2026

Study information

• Verified date: February 2024
• Source: Bournemouth University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study evaluates the effect of slow and deep breathing on lowering blood pressure in women with pregnancy-induced hypertension. Slow and deep breathing will be practised daily for 10 minutes from enrolment until the woman gives birth. This feasibility study aims to investigate the practicality of conducting a proposed future randomised controlled trial.

Description:

In addition to the slow and deep breathing intervention the women will undertake a short protocol investigating the physiological responses to slow and deep breathing during their initial meeting. The women will undertake 4 separate 5-min breathing exercises with a 5 minute rest period between each exercise. The breathing exercises are normal breathing, and fixed breathing frequencies of 4, 6 and 8 breaths per minute. Blood pressure, heart rate and breathing rate will be monitored continuously, and non-invasively, throughout each breathing protocol. The women will also have the opportunity to provide feedback on the intervention and their experiences in an online survey at 36 weeks gestation.

Recruitment information / eligibility

• Status: Suspended
• Enrollment: 67
• Est. completion date: December 2026
• Est. primary completion date: December 2026
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Diagnosed with pregnancy-induced hypertension (PIH). Defined as "new hypertension presenting after 20 weeks of pregnancy without significant proteinuria (urinary protein:creatinine ratio greater than 30mg/mmol" by NICE guidelines (2010) OR diagnosed as having one-off high blood pressure but at risk of developing PIH;
• Single pregnancy;
• Capable of giving informed consent;
• Age over 18.

Exclusion Criteria:

• Under 18 years old;
• Referred immediately to obstetric-care after PIH diagnosis for an immediate intervention, with systolic blood pressure over 160 mmHg or diastolic blood pressure over 100 mmHg;
• Multiple pregnancy (twins, triplets, etc.);
• Current smoker;
• Current diagnosis of respiratory diseases; asthma, COPD (Chronic Obstructive Pulmonary disease), bronchitis. (A previous occurrence or diagnosis that has not been present for longer than 1 year ago does not exclude participants, i.e. childhood asthma);
• Allergy/reaction to gel used on ECG tabs;
• Vulnerable participants who are unable to give informed consent.

Related Conditions & MeSH terms

• Hypertension
• Hypertension, Pregnancy-Induced
• Pregnancy-Induced Hypertension

Intervention

Other:
• Slow and deep breathing
Please see arm description

Locations

Country	Name	City	State
United Kingdom	Bournemouth University	Bournemouth
United Kingdom	University Hospitals Dorset NHS Foundation Trust	Poole

Sponsors (1)

Lead Sponsor	Collaborator
Bournemouth University

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Proportion of women eligible to participate in study	Proportion of women eligible to participate in the study (using inclusion and exclusion criteria) against number of women who attend the antenatal unit for high blood pressure	5 months (From start to end of recruitment period)
Other	Recruitment rates of participation using a hospital antenatal unit	Proportion of women participating in the study against number of eligible women who attend the antenatal unit	5 months (From start to end of recruitment period)
Other	Proportion of women who would be willing to be randomised in future trials	Proportion of women who would be willing to be randomised in a future trial (asked in post-questionnaire) against those who would not be willing to be randomised	Between gestational age 36 weeks and birth. If participant gives birth prior to 36 weeks they will be invited to participate in the questionnaire when appropriate, but before 36 weeks
Other	Adherence to self-monitoring of daily blood pressure	Proportion of days blood pressure recorded per participant and average proportion of days blood pressure recorded	Up to 22 weeks (From enrolment to giving birth)
Other	Proportion of women withdrawing	Proportion of women who do not contribute data due to premature delivery, drop-out or worsening high blood pressure	Up to 22 weeks (From enrolment to giving birth)
Other	Difference in blood pressure	Average week 1 blood pressure compared with average last week blood pressure (last week prior to giving birth)	Up to 22 weeks (From enrolment to giving birth)
Other	Practicality of protocol in delivering slow and deep breathing as an intervention to treat high blood pressure during pregnancy.	Women's perceptions of the intervention, as assessed using the post-questionnaire. The questionnaire includes open ended questions on experiences and barriers to completing the intervention. Likert scale (strongly agree, agree, uncertain, disagree, strongly disagree) questions are also included.	Between gestational age 36 weeks and birth. If participant gives birth prior to 36 weeks they will be invited to participate in the questionnaire when appropriate, but before 36 weeks
Other	Heart rate responses to slow and deep breathing	Differences in heart rate between breathing protocols (5 minutes of breathing at 4, 6, and 8 breaths per minute and normal breathing)	Day 1
Other	Blood pressure responses to slow and deep breathing	Differences in blood pressure between breathing protocols (5 minutes of breathing at 4, 6, and 8 breaths per minute and normal breathing)	Day 1
Other	Stroke volume responses to slow and deep breathing	Differences in stroke volume between breathing protocols (5 minutes of breathing at 4, 6, and 8 breaths per minute and normal breathing)	Day 1
Other	Cardiac output responses to slow and deep breathing	Differences in cardiac output between breathing protocols (5 minutes of breathing at 4, 6, and 8 breaths per minute and normal breathing)	Day 1
Primary	Adherence to the breathing exercise intervention	Proportion of days breathing exercise completed per participant and average proportion of days breathing exercise completed	Up to 22 weeks (From enrolment to giving birth)
Secondary	Proportion of women referred to obstetric-led care	Referral to obstetric-led care will be on the grounds of a test result of 30 mg/mmol^1 in a spot urinary protein, symptom exacerbation and/or increase in systolic and/or diastolic blood pressure	Up to 22 weeks (From enrolment to giving birth)