Impaired lung mechanics, obesity, and regional lung injury during robotic assisted laparoscopic surgery - obesity is a global epidemic affecting more than 40% of the united states population

The National Institutes of Health National Heart Lung and Blood Institute awarded the University of Vermont & State Agricultural College $184,788 on July 1, 2026, under the Cardiovascular Diseases Research program (CFDA 93.837) to investigate impaired lung mechanics, obesity, and regional lung injury during robotic-assisted laparoscopic surgery.

The research examines how obesity alters lung mechanics and increases the risk for intraoperative and postoperative pulmonary complications in patients undergoing mechanical ventilation. The project focuses on the mechanistic relationship between impaired regional lung mechanics and lung injury during robotic-assisted laparoscopic surgery in the head-down position, where abdominal insufflation and positioning compress the lungs. Prior studies by the research team identified body mass index as a prime determinant of mechanical impairment during these procedures, with evidence of tissue damage and alveolar-capillary leak in bronchoalveolar lavage fluid from affected patients. The work aims to inform refinement of lung-protective ventilation methods for obese surgical patients, representing an unmet need in perioperative anesthesiology.

The award is structured as a Project Grant (K23 mechanism) with a period of performance from July 1, 2026, through June 30, 2031. Performance occurs in Burlington, Vermont.

Patients with obesity have altered lung mechanics that make them difficult to ventilate in the operating room and double the risk for intraoperative or postoperative pulmonary complications. The causes of these poor outcomes are unknown, and reflect an incomplete knowledge of how obesity impacts lung mechanics during mechanical ventilation. As millions of patients require surgery with anesthesia and mechanical ventilation each year, safe lung protective ventilation (LPV) methods for patients with obesity represent a major unmet need in anesthesiology. LPV methods were designed to prevent ventilator induced lung injury in patients with acute respiratory distress syndrome. While adoption of LPV for intraoperative ventilation led to a reduction in postoperative pulmonary complications, concerted efforts to further refine intraoperative ventilation methods have yielded marginal improvements in outcomes. The dynamic interactions between a patient's lungs and the mechanical ventilator can lead to complex regional impairments in lung mechanics. The lack of data evaluating the mechanistic relationship between impaired regional lung mechanics and lung injury is preventing improvements in care. A particularly challenging scenario is robotic-assisted laparoscopic surgery (rals) in a 30° head-down position, which is required for most urologic or gynecologic surgeries. Abdominal insufflation and head-down positioning compress the lungs. Our prior studies suggest that body mass index (BMI) is a prime determinant of mechanical impairment during rals, leading to both atelectasis and tidal alveolar recruitment and collapse. We found direct evidence of tissue damage and alveolar-capillary leak in bronchoalveolar lavage fluid (balf) from these patients. These results lead US to hypothesize that patients with obesity undergoing rals are at high risk for developing the form of acute lung injury known as atelectrauma, despite using LPV. The goal of the proposed research is to define the links between regional intraoperative lung mechanics and lung injury, and then to use these data to improve the pulmonary care of patients with obesity undergoing rals. Specific aim 1 is to delineate relationships between regional lung mechanics, biomarkers of lung injury, and obesity in a cross-sectional study of intraoperative ventilation and biomarkers of lung injury. In specific aim 2, we will apply individualized positive end-expiratory pressure (peep) titration in a pilot cohort of patients with BMI ≥ 35 KG/M2, testing whether improved lung mechanics reduce regional markers of alveolar-capillary injury. Understanding the relationship between regional ventilation mechanics and lung injury is a critical step towards personalized LPV strategies. Our integrated approach will validate ventilation interventions for patients with obesity. The training proposed will achieve the short-term goals of developing expertise in lung biology, bioinformatics, ventilation mechanics, and clinical study design, while rigorously preparing the applicant for an independent scientific career dedicated to improving the perioperative care of patients with obesity.