Study on Baroreceptor Function in Relation to Orthostatic Blood Pressure Regulation After Hip Surgery

• Conditions: Total Hip Replacement; Hypotension, Orthostatic

• Registration Number: NCT01866787
• Lead Sponsor: Rigshospitalet, Denmark

Brief Summary

The purpose of this observational study is to evaluate the baroreceptor function in relation to surgical inflammation and orthostatic intolerance after elective hip arthroplasty.

The main hypothesis is that baroreceptor function is attenuated after surgery and related to surgical inflammation.

Detailed Description

Orthostatic intolerance and hypotension is prevalent during early mobilization after major surgery.

This observational study aims to evaluate the baroreceptor function during using a standardized evaluation protocol before, 6- and 24 hours after elective primary unilateral hip-arthroplasty.

The study hypothesis is that baroreceptor function as expressed by the valsalva ratio is attenuated after surgery and related to surgical inflammation.

Study Timeline

• Study Start: 2013-01
• Study First Submitted: 2013-02-04
• Study First Submitted QC: 2013-05-27
• Study First Posted: 2013-05-31
• Status Verified: 2015-01
• Last Update Submitted: 2015-01-15
• Last Update Posted: 2015-01-16
• Primary Completion: 2015-12
• Study Completion: 2015-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 30

Inclusion Criteria

• Scheduled for unilateral hip arthroplasty
• 18 years or older
• Able to give informed consent

Exclusion Criteria

• American Society of Anesthesiologists (ASA) class 3 or higher
• Chronic arrythmia (Atrial fibrillation or other arrythmia)
• Incompensated ischaemic heart disease
• Mobilization restriction due to surgical reasons
• Medical complications during admission requiring transferral to other department

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Change in baroreceptor function from preoperatively to 6 hours after surgery	6 hours after surgery	Change in baroreceptor function as expressed by change in the blood pressure valsalva ratio during a standardized assessment before and 6 hours after surgery.

Secondary Outcome Measures

Name	Time	Method
Orthostatic Hypotension	Preoperative, 6 and 24 hours postoperative.	orthostatic hypotension defined according to international guidelines.
Orthostatic response in blood pressure	Preoperative, 6 and 24 hours after surgery	The response in systolic and diastolic blood pressure during postural change from supine to standing
Inflammatory markers	preoperative, 6 and 24 hours postoperative	Inflammatory markers (CRP and interleukin-6) measured at 3 separate timepoint: preoperative, 6- and 24 h after surgery
Orthostatic response in heart rate variability	preoperative, 6 and 24 hours postoperative	Heart rate variability during supine rest, sitting and standing as assessed by Spectral analysis.
Orthostatic intolerance	preoperative, 6 and 24 hours after surgery	Orthostatic intolerance defined as the inability to sit or stand for 3 minutes due to presyncopal symptoms (Dizziness, Nausea, Blurred vision).
Baroreceptor function	On the day of surgery: preoperatively, 6- and 24 hours after surgery	baroreceptor function as expressed by change in the blood pressure valsalva ratio during a standardized assessment

Trial Locations

Locations (1)

Frederiksberg Hospital, Department of orthopaedic surgery; 🇩🇰 Frederiksberg, Denmark