Gastroesophageal Reflux and Respiratory Function in Patients Undergoing Abdominoplasty

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

• Ages Up to 60 years
• Women only
• Healthy volunteers accepted
• Child, Adult

Study population: The study population will consist of adult women, with and without a diagnosis of GERD and with and without a history of abdominoplasty. After confirmation of eligibility criteria, participants will be assigned to three study groups based on their clinical and surgical characteristics: GERD + abdominoplasty group (GERD+AP), GERD group (GERD), and abdominoplasty group (AP).

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

About this study

Official title: Gastroesophageal Reflux, Diaphragmatic Mechanics, Respiratory Muscle Function, and Thoracoabdominal Kinematics in Patients Undergoing Abdominoplasty: a Cross-sectional Study

Conditions

Abdominoplasty, Diaphragm, Respiratory Mechanics, Gastroesophageal Reflux Disease

Being tested

Assessment of anthropometric and sociodemographic data and clinical history, Assessment of Symptoms, Quality of Life, and Physical Activity, Spirometric assessment, Manovacuometry assessment, Ultrasound Assessment of the Diaphragm, Abdominal Core, and Sternocleidomastoid

Medical subject headings

Gastroesophageal Reflux

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

• Assessment of anthropometric and sociodemographic data and clinical historyOther

  The initial assessment will be conducted using a standardized form developed by the researchers, covering sociodemographic data (age, sex, ethnicity, education level, occupation), anthropometric data (weight, height, body mass index, waist circumference), a clinical history of symptoms (onset, weekly frequency, time of peak occurrence, triggering factors, use of antacids, psychosocial factors, alarm symptoms, presence of comorbidities, smoking, alcohol consumption, and history of thoracoabdominal surgeries), and a physical examination.

• Assessment of Symptoms, Quality of Life, and Physical ActivityOther

  GERD-related symptoms will be assessed using the Gastroesophageal Reflux Disease Symptom Questionnaire (QS-DRGE), which has been validated for the Portuguese language. Disease-related quality of life will be assessed using the GERD-HRQL questionnaire (Appendix B), translated into Portuguese. Physical activity levels will be assessed using the short version of the International Physical Activity Questionnaire (IPAQ), validated for the Portuguese language. Both instruments will be administered individually by a previously trained researcher in a private setting during the initial assessment. Participants will complete the questionnaires via a structured interview, with any questions clarified without influencing the responses.

• Spirometric assessmentOther

  Pulmonary function will be assessed via spirometry using a Micro Medical MicroLoop MK8 spirometer (England), calibrated daily with a 3-liter syringe in accordance with American Thoracic Society/European Respiratory Society (ATS/ERS) recommendations. The following parameters will be measured: slow vital capacity (SVC), inspiratory capacity (IC), forced vital capacity (FVC), forced expiratory volume in the first second (FEV₁), FEV₁/FVC ratio, and peak expiratory flow (PEF). Tests will be conducted in a suitable environment by a trained evaluator, with participants seated and wearing a nose clip, following instructions and a prior demonstration of the maneuvers. At least three acceptable and reproducible forced expiratory maneuvers will be performed, and the best values obtained will be used. Interpretation will be based on reference equations for the Brazilian population, with biosafety measures implemented throughout the procedure.

• Manovacuometry assessmentOther

  Respiratory muscle strength will be assessed via manovacuometry using the MVD 300 U HOMED device, in accordance with American Thoracic Society/European Respiratory Society (ATS/ERS) recommendations. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) will be measured. Participants will remain seated without back support, with the trunk upright, head in a neutral position, and feet resting on the floor, while using a nose clip and a mouthpiece with an adequate seal. MIP will be obtained following maximal expiration to residual volume, followed by maximal inspiration against an occluded airway, whereas MEP will be measured following maximal inspiration to total lung capacity, followed by forced expiration against the occluded mouthpiece. Three to five acceptable and reproducible maneuvers will be performed, and the highest value obtained will be recorded. Interpretation will be based on reference equations for the Brazilian population.

• Ultrasound Assessment of the Diaphragm, Abdominal Core, and SternocleidomastoidOther

  Diaphragmatic mechanics and the thickness of the abdominal core muscles and sternocleidomastoid will be assessed via ultrasound using a LOGIQ-V2 (General Electric) system. Participants will be positioned in a semi-reclined supine position (30°-45°). A convex transducer (3.5 MHz) will be used to measure diaphragmatic mobility in M-mode, while a linear transducer (7 MHz) will be used to assess diaphragmatic thickness, the thickening fraction, and the thickness of the rectus abdominis, internal and external obliques, transversus abdominis, and sternocleidomastoid muscles in B-mode. Mobility will be recorded during quiet breathing and deep inspiration, whereas muscle thickness will be measured at the end of expiration and at maximal inspiration. At least three consecutive measurements will be performed for each variable, and the mean value will be used. All procedures will follow previously validated protocols and standardized verbal commands to ensure measurement reproducibility.

• Assessment of respiratory muscle enduranceOther

  Inspiratory muscle endurance will be assessed using the POWERbreathe® KH2 (Powerbreathe International Ltd.) with a load set at 60% of the maximal inspiratory pressure (MIP) previously determined via manovacuometry. The test will be conducted in a controlled environment using calibrated equipment and administered by a trained evaluator, following instructions and a demonstration of the technique. Participants will remain seated with their trunks upright, heads in a neutral position, and feet resting on the floor, while using a nose clip and a mouthpiece with a proper seal. Cycles of rapid, vigorous inspiration against resistance,followed by passive expiration,will be performed for up to 10 minutes or until the limit of tolerance is reached. Heart rate and peripheral oxygen saturation will be measured before and after the test. The device will automatically record inspiratory power, energy, inspiratory volume and flow, endurance time, S-Index, peak inspiratory flow, and the number of bre

• Thoracoabdominal kinematicsOther

  Thoracoabdominal kinematics will be assessed using optoelectronic plethysmography (OEP BTS Bioengineering®, Milan, Italy) in a room equipped with a system of pre-calibrated, synchronized infrared cameras. Participants will remain seated with an upright trunk and the head in a neutral position, while 89 reflective markers are attached to standardized anatomical landmarks on the chest and abdominal walls. The system will perform a three-dimensional reconstruction of the thoracoabdominal surface and calculate respiratory volumes via mathematical integration. During data acquisition, participants will breathe quietly for 3 minutes. The following parameters will be analyzed: total chest wall volume (Vcw); the volumes of the pulmonary rib cage (Vrc,p), abdominal rib cage (Vrc,a), and abdominal (VAb) compartments; their relative contributions to tidal volume (%Rc and %Ab); and the absolute change in abdominal volume (ΔVAb).

• Body bioimpedance assessmentOther

  Body composition will be assessed via multifrequency electrical bioimpedance using the InBody 120® to characterize the sample and control for confounding factors. Participants will be instructed to fast for at least four hours; avoid alcohol for the preceding 48 hours; avoid intense physical activity, caffeine, and thermogenic supplements for the preceding 24 hours; maintain their usual hydration; empty their bladder before the test; remove metal objects; and wear light clothing. Assessments will follow the manufacturer's recommendations, with the participant standing barefoot, maintaining proper contact with the electrodes, and resting for five minutes beforehand. Tests involving movement or loss of contact will be repeated. The following variables will be obtained: body fat index, skeletal muscle mass, fat-free mass index, total fat mass, total and segmental body fat percentage, segmental lean mass, waist-to-hip ratio, total body water, and estimated ideal weight.

What is being measured

The primary outcome is the main question the study is designed to answer.

1. Diaphragmatic mobility

   Measured: 1 day

2. Diaphragmatic Thickness

   Measured: 1 day

3. Diaphragmatic contraction velocity

   Measured: 1 day

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

1. First posted9 Oct 2026
2. Study startNov 2026 (estimated)
3. Primary completionOct 2027 (estimated)
4. Study completionFeb 2028 (estimated)

Resources

• Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
• Other trials for AbdominoplastyStudies of the same condition, open and under way.
• What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.