Hypohydration and Cardiorespiratory Function

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

26 participants

Study Classification

INTERVENTIONAL

Study Start Date

2014-02-28

Study Completion Date

2014-07-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Major non-cardiac surgery has a high degree of morbidity and mortality. Recently, measurement of a patient's preoperative cardiorespiratory reserve, performed non-invasively by cardiopulmonary exercise testing, has been shown to be predictive of outcome following non-cardiac surgery. All patients prior to major surgery are starved for a minimum of 6 hours and often longer prior to major elective surgery. It has been shown that elite athletes who are hypohydrated have reduced exercise capacity and lower cardiorespiratory function. These results are further exaggerated in "non-trained" individuals. Therefore, the starvation policy prior to surgery may have a deleterious effect on outcome after surgery.

4.2 AIMS This is a pilot study of health volunteers to assess the role of carbohydrate (CHO) (preload) and carbohydrate-protein (CHO-P) (Highfive energy source 1 in 4) in improving aerobic capacity after a period of fasting mimicking the current starvation policy prior to surgery. Both of these have similar calorific value and only differ in the amount of carbohydrate and protein supplementation.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Dehydration and Population Health

NCT04502238

Dehydration (Physiology)

UNKNOWN

Changes in Body Water During Surgery

NCT05272540

Postoperative Complications Bioelectrical Impedance Hospital Stay +1 more

COMPLETED

The Relation Between Preoperative ScO2 and the Postoperative Course of Humoral Organ Dysfunction Markers.

NCT01409941

Patients Undergoing Cardiac Surgery

COMPLETED

Prevalence of Preoperative Dehydration in Major Elective Urologic Surgery and Its Impact on Postoperative Outcome

NCT03788070

Dehydration Postoperative Nausea and Vomiting Postoperative Complications

TERMINATED

Volume Deficit Prior to Surgery

NCT00380107

Hypovolemia Surgery

COMPLETED

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

2 OUTLINE OF STUDY METHODOLOGY (See Appendix D) The methodology of the testing is outlined below:-

STARVATION POLICY The three exercise tests will be undertaken on three separate days but at the same time in the morning to minimise the starvation time and ensure consistency. All patients will be asked not to partake in strenuous exercise 24 hours prior to the test as this could affect hydration and performance status.

Starvation exercise test Participants will be asked to starve from midnight prior to the test. They may have a small glass of water at 6am on the day of the test. This is in line with the current starvation policy at the Freeman Hospital.

CHO loaded test Participants will be asked to drink an isotonic carbohydrate loaded drink (preload) appendix E the night before the test and also two hours prior to the CPX test. This type of clear drink has been shown to be emptied from the stomach within 2 hours and as such can be administered safely on the day of surgery. They again will be asked to starve from midnight prior to the test.

CHO-P loaded test

Participants will be asked to drink an isotonic carbohydrate drink (Highfive energy source 4:1) the night prior to the test and also two hours prior to the CPX test. Again, it has been shown that this type of drink is emptied from the stomach rapidly. They again will be asked to starve from midnight of the test

CARDIOPULMONARY EXERCISE TESTING

Cardiopulmonary exercise measurements are conducted in the consistent environment of the preassessment clinic in Clinic H, Freeman Hospital. CPX equipment includes an electronically braked cycle ergonometer, 12 lead ECG and a metabolic cart. The ECG allows online monitoring of all leads for rate and rhythm, and can measure changes in any S-T segment depression/elevation suggestive of cardiac ischaemia. The metabolic cart has oxygen and carbon dioxide analysers with a response time enabling breath-by-breath measurement. Calibration is ensured before each test. VO2, VCO2, heart rate, minute ventilation, and work rate are displayed continuously throughout the test.

Setting up the CPX test Patients have ECG leads applied before getting on the bike, and are coached on the mouthpiece and communication during the test. They are instructed to give their 'best effort' but to stop if they feel dizzy or faint. The increment in work rate is predetermined using equations for an estimate of expected work capacity, to aim for the test duration to be approximately 6-10 minutes.

CPX Test protocol Initially, 2 - 5 minutes of resting data is performed, ensuring patient comfort, and that the Respiratory Exchange Ratio (RER) falls below 1, indication the patient is not hyperventilating. Next, there is 1-3 minutes of unloaded cycling, followed by a graded increase in incremental workload. The leg speed throughout the test is maintained at 50-60 rpm to ensure constant effort. The patient is given verbal feedback and encouragement throughout the test. The test is stopped by the patient due to fatigue, pain, light headedness, or when they fail to maintain greater than 30 rpm for more than one minute despite encouragement. On completion of the exercise phase of the test, the patient is further monitored during the recovery period until heart rate reaches within 10% of pre-test, and all ST segments have normalised if applicable.

Exercise data processing Results are presented in standard nine-panel format compiled by CPX software. Further analysis for sub maximal parameters related to cardiopulmonary reserve is undertaken by trained personnel

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Dehydration

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

NON_RANDOMIZED

Intervention Model

SINGLE_GROUP

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

DOUBLE

Participants Investigators

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.