Clinical Research Directory

Pneumoperitoneum Pressure and Lung Ultrasound Atelectasis

Elective laparoscopic cholecystectomy may lead to perioperative atelectasis due to pneumoperitoneum-related diaphragmatic elevation and impaired respiratory mechanics. Lung ultrasound (LUS) provides a noninvasive bedside method for evaluating perioperative aeration loss. This prospective randomized controlled study aims to compare the effects of low-pressure (10 mmHg) and standard-pressure (14 mmHg) pneumoperitoneum on perioperative atelectasis assessed by LUS in patients undergoing laparoscopic cholecystectomy under general anesthesia. Changes in LUS scores, respiratory mechanics, oxygenation, and postoperative clinical outcomes will also be evaluated.

Effect of Positioning and ACBT on Pulmonary Complications After Cardiac Surgery

The goal of this quasi-experimental clinical trial is to learn if position management combined with the Active Cycle of Breathing Techniques (ACBT) works to reduce postoperative pulmonary complications in adult patients undergoing elective cardiac surgery. It will also evaluate the individual effects of each technique compared to routine care. The main questions it aims to answer are: Does the combination of positioning and ACBT significantly lower the incidence and severity of postoperative pulmonary complications (like atelectasis, pneumonia, and respiratory failure) within the first 7 days after surgery? Does the combination of these techniques reduce the length of hospital stay compared to using each technique alone or routine care? Does the application of ACBT alone lower the rate of respiratory infections? Does position management alone improve oxygenation parameters (such as SpO\_{2} and PaO\_{2})? Researchers will compare four groups of patients to determine the most effective nursing approach: Group 1 (Control Group): Participants will receive routine postoperative hospital care only. Group 2 (ACBT Group): Participants will perform the Active Cycle of Breathing Techniques (breathing control, thoracic expansion, and huffing) three times daily for 10-15 minutes over 5 postoperative days. Group 3 (Positioning Group): Participants will receive structured position management exclusively, shifting from head elevation (30-45) early after surgery to a semi-recumbent position (approx60) during waking hours, alongside other positions like lateral or forward-leaning as tolerated. Group 4 (Combined Group): Participants will receive both structured position management and perform the ACBT sessions according to the same schedules. All participants will undergo daily respiratory assessments using a standardized scoring system for 7 days post-surgery or until hospital discharge.

Bronchoscopic Airway Clearance for Improving Lung Aeration in Mechanically Ventilated Patients With Atelectasis

The goal of this clinical trial is to learn whether bedside flexible bronchoscopy-guided airway clearance can improve lung aeration in adult patients who are receiving invasive mechanical ventilation and have atelectasis with a high airway secretion burden. The main questions it aims to answer are: Does bedside flexible bronchoscopy-guided airway clearance reduce the proportion of nonaerated lung tissue from baseline to day 5? Does this treatment improve other lung aeration measures, respiratory mechanics, arterial blood gas parameters, pulmonary infection score, ventilator-free days, intensive care unit length of stay, and safety outcomes? Researchers will compare usual airway care plus bedside flexible bronchoscopy-guided airway clearance with usual airway care alone to see if bronchoscopy-guided airway clearance improves lung aeration and clinical outcomes. Participants will be randomly assigned to one of two groups. Participants in the usual care group will receive standard airway management, which may include airway suctioning, postural drainage, humidification, chest physiotherapy, and other routine respiratory care. Participants in the bronchoscopy group will receive the same usual care, plus bedside flexible bronchoscopy-guided airway clearance when predefined criteria for high airway secretion burden are met. Participants will have clinical assessments during the study, including chest imaging, respiratory mechanics measurements, arterial blood gas tests, pulmonary infection score assessment, and safety monitoring. The main assessment will compare quantitative chest computed tomography findings at baseline and day 5 to evaluate changes in nonaerated lung tissue.

Low-Flow Anesthesia and Perioperative Atelectasis in Laparoscopic Bariatric Surgery

The goal of this clinical trial is to learn whether low-flow anesthesia reduces perioperative atelectasis compared to normal-flow anesthesia in adults undergoing laparoscopic bariatric surgery. The main questions it aims to answer are: Does low-flow anesthesia result in a smaller increase in lung ultrasound score from baseline to postoperative hour 1? Does low-flow anesthesia result in better preservation of pulmonary function at postoperative hour 48? Researchers will compare low-flow anesthesia (fresh gas flow 0.5 L/min) to normal-flow anesthesia (fresh gas flow 2 L/min) to see if low-flow anesthesia reduces the extent of perioperative atelectasis as measured by lung ultrasound. Participants will: Be randomly assigned to receive either low-flow or normal-flow inhalational anesthesia with sevoflurane during surgery Undergo lung ultrasound assessments before surgery and at postoperative hours 1 and 24 Undergo spirometric testing one day before surgery and at postoperative hour 48

Optimal Interval for Periodic Alveolar Recruitment Maneuvers Achieving 90% Lung Re-expansion During Intraoperative Ventilation

This study aims to determine the optimal interval for periodic alveolar recruitment maneuvers (PARM) that can achieve effective lung re-expansion in 90% of patients undergoing intraoperative mechanical ventilation during abdominal laparoscopic surgery in the low Trendelenburg position. Identifying the most effective frequency of PARM is crucial for establishing lung-protective ventilation strategies, with the ultimate goal of reducing intraoperative atelectasis, decreasing postoperative pulmonary complications, and accelerating recovery. Patients are randomized using a biased-coin sequential design. PARM is initially applied every 0.5 hours, and the effectiveness of lung re-expansion is evaluated before the end of surgery. The primary outcome is the effectiveness of recruitment, assessed by a combination of lung ultrasound scores and shunt fraction. Secondary outcomes include mechanical power at the end of surgery, time-weighted average mechanical power during ventilation, postoperative P/F ratio, dead space fraction, air test results, intraoperative adverse events, incidence of respiratory failure in the PACU and postoperative period, and postoperative length of stay. This trial is expected to provide robust evidence for defining the optimal RM interval in protective ventilation protocols for patients undergoing laparoscopic abdominal surgery, thereby contributing to improved perioperative respiratory outcomes.

Predictive Value of Ariscat Index In The Development of Pulmonary Complication After Major Abdominal Cancer Surgery

The term postoperative pulmonary complication is the development of any complications affecting the respiratory system after anesthetic and surgery procedures. The ARISCAT risk assessment score is a seven-variable regression model that divides patients into low, moderate, and high-risk groups. In this study, the investigators aimed to investigate the effectiveness of the ARISCAT risk scoring index in predicting postoperative pulmonary complication development in patients scheduled for major abdominal cancer surgery.

Bedside Lung Ultrasound to Monitor Lung Recruitment in Obese Patients

Patients with morbid obesity who require a breathing machine (mechanical ventilator) in the Intensive Care Unit (ICU) frequently experience partial lung collapse. This happens because the extra weight of the chest and abdomen presses on the lungs, reducing their capacity and making it difficult to maintain adequate oxygen levels. To address this, doctors often perform a standard lung recruitment maneuver, which involves temporarily increasing the air pressure from the ventilator to gently pop open the collapsed lung areas. However, standard bedside monitoring tools make it difficult to see exactly how well the different regions of the lungs are reopening. This prospective observational study aims to evaluate the use of Bedside Lung Ultrasound (LUS), which is a safe, radiation-free imaging tool, to monitor how well the lungs respond to these maneuvers in real-time. During the study, researchers will use a standardized 12-zone ultrasound scan to examine the lungs of mechanically ventilated adult patients (BMI ≥ 33 kg/m²) before, during, and after a step-by-step lung recruitment maneuver. By calculating a "Total Lung Ultrasound Score," the medical team can directly visualize and measure the transition from collapsed tissue to normal, aerated lung tissue. Furthermore, the ultrasound will be used during a step-down pressure phase to help identify the patient's "optimal PEEP" (Positive End-Expiratory Pressure), which is the exact customized pressure needed to keep the lungs open after the maneuver is complete, thereby improving oxygenation and minimizing the risk of lung injury.

Effects of Periodic Recruitment Maneuvers on Atelectasis and Respiratory Mechanics During Elective Spine Surgery Assessed by Lung Ultrasonography

During general anesthesia, particularly in patients undergoing spine surgery in the prone (face-down) position, increased intrathoracic and abdominal pressure may reduce lung compliance and promote the development of atelectasis (partial lung collapse). Atelectasis can impair intraoperative oxygenation and may increase the risk of postoperative pulmonary complications. Alveolar recruitment maneuvers (ARM) are routinely used in anesthesia practice to reopen collapsed lung regions; however, it remains unclear whether periodic application of ARM throughout surgery provides additional benefit compared with standard single-time application. This prospective, randomized controlled clinical study aims to evaluate whether periodic alveolar recruitment maneuvers applied during elective spine surgery in the prone position reduce intraoperative atelectasis and improve respiratory mechanics compared with the standard approach of performing ARM only after positioning and before extubation. Adult patients undergoing elective spine surgery under general anesthesia will be randomly assigned to either a periodic ARM group or a standard ARM group. Lung aeration will be assessed using lung ultrasound, a non-invasive and radiation-free bedside imaging method. The primary outcome is the incidence of intraoperative atelectasis assessed before extubation. Secondary outcomes include lung ultrasound aeration scores, respiratory mechanics parameters (such as airway pressures and compliance), oxygenation indices, and the occurrence of transient intraoperative respiratory or hemodynamic events. The findings of this study may help optimize intraoperative ventilation strategies in prone spine surgery and contribute to improved perioperative respiratory safety.

The Effect of Oscillation and Lung Expansion (OLE) Therapy in Prolonged Mechanical Ventilated Patients With Atelectasis Evaluated in Multiple Methods

High frequency chest wall oscillation (HFCWO) is currently one of the most common and widespread mechanical airway clearance techniques (ACTs) in clinical practice in China. As an external airway oscillation technique, it has been proven in previous clinical practices that it can help clear secretions by vibrating the chest wall, loosening the secretions adhering to the airway walls and promoting ciliary movement, thereby improving lung ventilation and re-expansion. However, there are still some groups of patients for whom this technique is not suitable in clinical practice, such as those who are uncomfortable with the oscillation, have damaged skin on the chest and back, have unstable rib fractures, or have poorly positioned tracheostomy tubes. In recent years, integrating multiple techniques into a single treatment has become a trend. Among them, oscillation and lung expansion (OLE) combines continuous positive airway pressure (CPAP), continuous high-frequency oscillation (CHFO), and nebulization, which can effectively clear airway secretions and promote lung re-expansion. Currently, only a few studies have confirmed that OLE has a positive impact on improving respiratory function in patients with acute respiratory failure, severe burns, and after lung surgery. This study aims to further compare the effects of the above two mechanical ACTs on improving lung ventilation and re-expansion by electrical impedance tomography (EIT), and optimize the clinical practice of physical therapists.

Open Lung Protective Extubation Following General Anesthesia

Perioperative respiratory complications are a major source of morbidity and mortality. Postoperative atelectasis plays a central role in their development. Protective "open lung" mechanical ventilation aims to minimize the occurrence of atelectasis during the perioperative period. Randomized controlled studies have been performed comparing various "open lung" ventilation protocols, but these studies report varying and conflicting effects. The interpretation of these studies is complicated by the absence of imagery supporting the pulmonary impact associated with the use of different ventilation strategies. Imaging studies suggest that the gain in pulmonary gas content in "open lung" ventilation regimens disappears within minutes after the extubation. Thus, the potential benefits of open-lung ventilation appear to be lost if, at the time of extubation, no measures are used to keep the lungs well aerated. Recent expert recommendations on good mechanical ventilation practices in the operating room conclude that there is actually no quality study on extubation. Extubation is a very common practice for anesthesiologists as part of their daily clinical practice. It is therefore imperative to generate evidence on good clinical practice during anesthetic emergence in order to potentially identify an effective extubation strategy to reduce postoperative pulmonary complications.

Automated Intraoperative Lung Recruitment Maneuvers in Major Laparoscopic Surgery

Laparoscopic colorectal surgery is associated with an increased risk of intraoperative atelectasis due to pneumoperitoneum, Trendelenburg positioning, and prolonged anesthesia duration. Atelectasis developing during surgery may persist into the postoperative period and contribute to postoperative pulmonary complications. Automated lung recruitment maneuvers delivered by modern anesthesia ventilators may offer a standardized method to improve lung aeration and reduce atelectasis. This prospective, randomized, single-center controlled trial aims to evaluate the effect of automated intraoperative lung recruitment maneuvers on atelectasis detected by lung ultrasonography in patients undergoing elective major laparoscopic colorectal cancer surgery. Adult patients will be randomized to receive either automated lung recruitment maneuvers or standard mechanical ventilation without recruitment. Lung ultrasonography will be used to assess atelectasis at predefined perioperative time points. The primary outcome is the incidence of atelectasis detected by lung ultrasound, and secondary outcomes include postoperative pulmonary complications, length of intensive care unit stay, length of hospital stay, and perioperative hemodynamic instability.

The Effect of the 5T Teach-Back Method on Respiratory Exercise and Incentive Spirometer Training

Breathing problems after surgery are common and can lead to serious complications such as low oxygen levels, lung collapse, or pulmonary embolism. These problems increase patient risk and place an additional burden on the healthcare system. Breathing exercises and incentive spirometer use are important methods to prevent these complications. However, many patients have difficulty understanding and correctly performing these exercises when education is limited to standard verbal instructions. This randomized controlled study aims to evaluate whether the 5T Teach-Back education method improves patients' understanding, practical skills, respiratory outcomes, and satisfaction compared with standard verbal education. The study will be conducted in a university hospital and will include 76 adult patients undergoing abdominal surgery under general anesthesia. Participants will be randomly assigned to either an intervention group or a control group. Patients in the intervention group will receive preoperative breathing exercise and incentive spirometer training using the 5T Teach-Back method, which encourages patients to explain the information back in their own words and repeat the skills until they are correctly understood. Patients in the control group will receive routine verbal education provided by clinical nurses. Outcomes will be measured before surgery and again within 24-72 hours after surgery. These outcomes include patients' knowledge level, correct performance of breathing exercises and spirometer use, respiratory rate, oxygen saturation, lung function test results, and patient satisfaction with nursing care. The results of this study are expected to show whether the 5T Teach-Back method is more effective than standard education in improving postoperative respiratory care and patient satisfaction. The findings may help standardize patient education practices and support nurses in delivering more effective respiratory training before surgery.

Clinical Utility of Portable Dynamic Chest X Ray (DDR) in the ICU

Dynamic digital radiography (DDR) is a new advanced version of chest radiography that captures dynamic images at a rate of 15 frames per second. It is coupled with an analytical software that allows it to provide more advanced measures of lung motion, ventilation, and perfusion compared to traditional chest radiography. While implementation of DDR fixed machines are beginning elsewhere in the US, this trial involves the first applications of an FDA-approved portable DDR machine, for use at the bedside in the ICU. The goal of this clinical trial is to determine the feasibility and safety of portable DDR technology in the ICU, as well as to evaluate the improved clinical diagnostic value of the portable DDR system over current standards of care. Participants will receive one to three sets of DDR images, which will then be compared to their clinical gold standard exams (such as chest x-rays, CTs, or VQ scans) to assess and improve the precision and accuracy of measurements such as diaphragmatic motion, lung movement, and perfusion.

Intraoperative Paravertebral Block and Postoperative Complications

This study aims to evaluate the clinical association between intraoperative paravertebral block and the reduction of postoperative complications following thoracic surgery.

VCV vs PRVC in Pediatric Anesthesia; an EIT- and LS-based Study

The primary objective of this study is to evaluate and compare the incidence and severity of intraoperative pulmonary atelectasis, measured by Lung Ultrasound Score (LUS) and EIT (Electrical Impedance Tomography), between two different modes of mechanical ventilation: Volume Control Ventilation (VCV) and Pressure Regulated Volume Control (PRVC/PCV-VG)

Physiological Effects and Safety of Continuous High-frequency Oscillatory Ventilation in Mechanical Ventilation Patients

Mechanical ventilation is an important treatment modality for intensive care unit (ICU) patients, but it also brings a series of problems such as ventilator-associated pneumonia, ventilator-induced lung injury, and atelectasis. Continuous High-Frequency Oscillation (CHFO )is often considered to have a protective effect on the lungs. CHFO provides effective gas exchange at supraphysiological frequencies while minimizing pressure fluctuations, producing tidal volumes smaller than dead space and adjusting around a continuously expanding pressure to optimize end-expiratory lung volume (EELV) by achieving and maintaining lung recruitment. However, the physiological effects and safety of CHFO in critically ill patients on mechanical ventilation lack relevant research. The objective of this research is to assess the feasibility, safety, and efficacy of CHFO in a population of mechanically ventilated critically ill patients.

To Assess the Effectiveness of Three Distinct Mechanical Assisted Sputum Evacuation Apparatuses in the Treatment of Patients With Mechanical Ventilation-induced Atelectasis

Retention of airway secretions is a common clinical problem in patients with mechanical ventilation. Effective removal of airway secretions requires a balance between the production and removal of airway secretions through the mucociliary transport system. Effective removal of airway secretions is the basic measure to maintain airway patency and normal alveolar ventilation and oxygenation. At present, a variety of mechanical assisted expectoration devices have been used to remove airway secretions in critically ill patients, including The MetaNeb® System(MetaNeb), High Frequency Chest Wall Oscillation(HFCWO) and (Cycloid Vibration Therapy)CVT. However, there is still a lack of sufficient evidence to evaluate the clinical efficacy of these three different mechanical assisted expectoration devices in airway management of patients with mechanical ventilation. This study aims to observe the clinical efficacy of three different mechanical assisted sputum evacuation devices in airway management of patients with mechanical ventilation atelectasis, and to provide a basis for optimizing the airway management scheme of patients with mechanical ventilation.

Regional Distribution of Ventilation at Different Respiratory Rates

This study will investigate the distribution of gas during mechanical ventilation in patients undergoing robot assisted laparoscopic prostatectomy. The gas distribution of ventilation are monitored and data extracted using electric impedance tomography in different respiratory rates.

Effect of Epidural Analgesia on Regional Lung Ventilation in Parturient Women as Assessed by Thoracic Impedance

The goal of this observational study is to learn more about the effect of obstetric epidural anesthesia on regional lung ventilation in healthy parturient women. The main question it aims to answer is whether the initiation or epidural analgesia improves or not regional lung ventilation in healthy women at term during labor. Participants will be subject to measurements of pulmonary impedance by electric impedance tomography before and after the start of epidural analgesia. No change will be applied to clinical care as a result of this measurement.