A constant or almost constant tidal volume (VT) is typically provided to patients receiving pressure- or volume-controlled invasive mechanical ventilation. On the other hand, numerous investigations reveal that even brief durations of constant VT ventilation (CVTV), utilizing little or large VTs, modify surfactant, elevate surface tension, induce atelectasis, create inflammatory cytokines, and result in ventilator-induced lung damage (VILI).1.
Because of the cyclical opening and closing of atelectatic airspaces (known as atelectrauma) and the overdistension of patent alveoli next to atelectatic regions (known as polytrauma), both of which are currently believed to cause VILI and result in systemic inflammation (known as biotrauma), atelectasis is a critical factor in this pathophysiology.Â
Sigh breaths did not significantly increase ventilator-free days compared with usual care alone in this randomized clinical trial involving 524 trauma patients with risk factors for developing acute respiratory distress syndrome (median ventilator-free days, 18.4 vs. 16.1, respectively). Sigh breaths were linked to improvements in secondary outcomes, such as all-cause mortality, even though they were not corrected for multiple tests. There was not a trace of damage. The study was published in JAMA Network.Â
According to the study, Ventilator-free days (VFDs) were the primary outcome measure, which is the total number of days without invasive ventilation up until day 28. Patients received zero VFDs if they passed away before day 28. Post hoc subgroup analyses were carried out on VFDs for variations in demographics for each of the previously mentioned ARDS risk variables, and injury severity was divided into two categories: above and below the median score.Â
The number of days without an ICU stay until day 28, problems determined by the patient’s treating physicians, and the discharge status were the predetermined secondary endpoints. Every endpoint, both primary and secondary, was predetermined.Â
Post hoc tertiary endpoints included time to successful extubation, use of sedatives, time to development of a Pao2 to fraction of inspired oxygen (Fio2) ratio consistent with ARDS and ARDS subgroups as defined by the Berlin criteria, and development of bilateral or diffuse infiltrates on chest imaging as determined from radiology reports. Total VFDs (TVFDs) were defined as the number of 24-hour periods free from assisted ventilation to day 28 or death.Â
Given the low incidence in both groups, this study was underpowered to detect clinically significant differences in the timing or number of patients developing ventilator-associated pneumonia or findings consistent with ARDS between the 2 treatment groups. Additionally, because of the pragmatic nature of the study design, blood gases and X-rays were not gathered consistently.
The fact that fewer patients died from traumatic brain injury or multiple traumas was a significant factor in the decreased mortality rate amongst those who received treatment. Sighs are justified because they lower VILI. Because of the potential relationship between stretch-activated mechanoreceptors and the immune response, sighs may have lessened the amount of VILI-associated biotrauma causing these injuries.Â
Sigh breaths were added to trauma patients undergoing mechanical ventilation who had risk indicators for acute respiratory distress syndrome. However, this did not significantly enhance the number of ventilator-free days in a pragmatic, randomized trial. Sighs appear to be well-tolerated and have the potential to enhance clinical results, according to defined secondary outcome data.Â
Reference Â
Albert RK, Jurkovich GJ, Connett J, et al. Sigh Ventilation in Patients With Trauma: The SiVent Randomized Clinical Trial. JAMA. Published online October 25, 2023. doi:10.1001/jama.2023.21739. Â
