Prehabilitation for Lung Cancer Patients Undergoing Lung Resection

Lung surgical resection is the gold standard treatment for earlier stages of lung cancer patients. Nevertheless, postoperative pulmonary complications (PPC) are frequent, related to morbidity and mortality, increasing length of hospital stay (LOS), hospital costs, delaying adjuvant treatments, and patients suffering. The PPC often occurs on postoperative days, even after hospital discharge. Prehabilitation might reduce PPC, although few studies have compared the effectiveness of different training protocols, and no information is available regarding the possible benefits of expiratory muscle training. Moreover, there are no comparisons of the cost-benefits of other protocols in patients submitted to lung resection surgery.

This project investigates the effectiveness of and compares four different prehabilitation protocols in reducing PPC and LOS in patients selected for lung cancer resections.

Participants will be individuals referred to surgical resection due to lung cancer. Patients who meet the inclusion criteria will be invited to participate in the study. After clinical data collection, patients will be randomly allocated (simple method) into four groups \[Control - CG, receiving an education session; Inspiratory muscle training group (IMT-G) receiving education session plus inspiratory muscle training (IMT); expiratory muscle training group (EMT-G) receiving education session plus expiratory muscle training (EMT); global exercise training group (GET-G) receiving education session plus a general exercise training (GET)\], and evaluated for functional capacity (pulmonary function, respiratory muscle function, physical fitness, daily physical activity, dyspnoea, fatigue, quality of life, anxiety, depression, and a 24-hour food diary. Afterward, all patients will receive an education class and written information regarding healthy habits to follow before, during, and after hospital discharge. Patients allocated to exercise groups will start the prehabilitation intervention for two weeks. After the intervention, patient assessments will be repeated. After that, patients will be submitted to surgery, and anesthetic and surgical procedure data will be collected. During hospital recovery, all patients will receive physiotherapy and any etiological complications and the LOS will be recorded according to medical criteria. After hospital discharge, PPC will be monitored and recorded for 30 days; by then, patients will be submitted to the final assessment.

To achieve the project's aim, sample size was calculated using G\*Power 3.1.9.2, based on an effect size of 0.33 reported by Cavalheri \& Granger (2017) in a study of preoperative exercise training and pulmonary complications after lung resection. With α = 0.05 and 95% power, a sample of 180 patients (45 per group) was determined. Accounting for a 10% dropout rate, the estimated total sample size is 200 patients.

The study was approved by the Ethical Committee from the Unidade Local de Saúde de São João (ULS São João), number (52/2024). All patients who meet the inclusion criteria, selected for pulmonary resections due to lung cancer, will be invited to participate in the study at the first preoperative appointment at the Cardiothoracic Department of the ULS São João. After signing the informed consent statement, a cod number will be attributed to the patients to protect his/her personal information. Participants will be randomized into one of the four groups: control group (CG), inspiratory muscle training group (IMT-G), expiratory muscle training group (EMT-G), and global exercise group (GET-G).

Assessments will be conducted at three time points: after obtaining written informed consent (baseline), after completing the prehabilitation program (post-intervention), and 30 days post-discharge (follow-up). Each assessment will take two days.

First day of assessments (data collection at the hospital):

A physician will carry one a medical assessment and collect data regarding anthropometric, sociodemographic, medical history, and behavioral risk factors. Following the medical assessment, a researcher will provide to the patients an accelerometer to measure daily physical activity. The accelerometers will be worn during waking hours until completing the prehabilitation program. Additionally, the researcher will collect data regarding patient-related outcome measures through questionaries (modified Medical Research Council Dyspnoea Questionnaire, International Physical Activity Questionnaire - Short Form, the Fatigue Assessment Scale, the Hospital Anxiety and Depression Scale, the EuroQol 5D-5L, food intake report from the day before (1-day recall)\]. Only in the baseline assessment, it will be placing the evaluation of barriers for prehabilitation. The researcher will then schedule the second day of assessment within the next three or four days.

Second day (data collection at Faculty of Sport of the University of Porto):

In the second day, patients will be evaluated for pulmonary function, respiratory muscle function, and functional capacity and physical fitness. Pulmonary function and respiratory muscle function will provide information on respiratory dynamics, including the absolute and predicted values of forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), Tiffeneau index (TI); total lung capacity (TLC), diffusion lung capacity for carbon monoxide (DLCO) and DLCO per unit alveolar volume (DLCO/VA). Regarding respiratory muscle function, maximal voluntary ventilation (MVV), maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP) will be measured. Thereafter, patients will be assessed for functional capacity / physical fitness \[aerobic endurance (6-minute walk test); lower body strength (30-second sit to stand), agility, coordination and dynamic balance (time up and go), balance (3 balance positions), speed walk (4 meters), lower body power (5-time sit to stand), handgrip strength\].

One week after the acceptance in participating in the study, the intervention program will start with an in-person education session for all patients, and those from the IMT-G, EMT-G and GET-G will thereafter start their 2-week training interventions at ULS São João. Detailed information of the training interventions is described in the Arms and Interventions section.

Following the intervention, all patients will be reassessed using the same procedures as at baseline, and then they will undergo the surgery. Information on ASA classification, ARISCAT score, minimum oxygen saturation, surgical approach, total surgical time, and extent of resection will be registered by the surgical team.

After surgery, all patients will receive standard care at the Cardiothoracic Department, including daily medical assessment, physiotherapy care, and analgesic protocol. Postoperative pulmonary complications (PPC) or from any other etiology, as well as the length of hospital stay (LOS), will be recorded. Any postoperative complication and hospital readmission in the next 30 days will be monitored and recorded. The criteria of PPC will be established according to the European Society of Thoracic Surgery and the Society of Thoracic Surgeons joint agreement and standardized definition (Fernandez et al., 2015).

Following hospital discharge, patients will be referred for outpatient physiotherapy and nursing care. Three weeks post-discharge, patients will have a medical appointment at the Cardiothoracic Department and scheduled for the post-discharge assessment. At this appointment, patients will receive an accelerometer to wear for one week, after which a follow-up assessment will be conducted. At the end of data collection, a cost effective analysis will be perfumed aiming to achieve the real economic cost-benefit of each protocol.

Eligibility Criteria:
Inclusion Criteria:

* Adult patients accepted for lung resection surgery, due to lung cancer, at the Cardiothoracic Department of Unidade Local de Saúde São João
* Not included in any type of prehabilitation program

Exclusion Criteria:

* Diagnosis of cardiac, or hematological or neurologic diseases
* Pulmonary hypertension
* Renal failure
* Patients that underwent previous thoracic surgery
* Patients submitted to pneumectomy
* Patients with cognitive and mental disorders
* Patients with impairments in autonomous deambulation
* Patients already included in any prehabilitation program