Driving pressure in mechanical ventilation: A review

Using a clinical decision support system to reduce excess driving pressure: the ALARM trial

BACKGROUND

Patients at need for ventilation often are at risk of acute respiratory distress syndrome (ARDS). Although lung-protective ventilation strategies, including low driving pressure settings, are well known to improve outcomes, clinical practice often diverges from these strategies. A clinical decision support (CDS) system can improve adherence to current guidelines; moreover, the potential of a CDS to enhance adherence can possibly be further increased by combination with a nudge type intervention.

METHODS

A prospective cohort trial was conducted in patients at risk of ARDS admitted to an intensive care unit (ICU). Patients were assigned to control or intervention by their date of admission: First, the control group was included without changing anything in clinical practice. Next, the CDS was activated showing an alert in the patient data management system if driving pressure exceeded recommended values; additionally, data on the performance of the wards were sent to the healthcare professionals as the nudge intervention. The main hypothesis was that this combined intervention would lead to a significant decrease in excess driving pressure.

RESULTS

The 472 included patients (230 in the control group and 242 in the intervention group) consisted of 33% females. The median age was 64 years; median Sequential Organ Failure Assessment score was 8. There was a significant reduction in excess driving pressure in the augmented ventilation modes (0.28 ± 0.67 mbar vs. 0.14 ± 0.45 mbar, p = 0.012) but not the controlled mode (0.37 ± 0.83 mbar vs. 0.32 ± 0.8 mbar, p = 0.53). However, there was no significant difference between groups in mechanical power, the number of ventilator-free days, or the percentage of patients showing progression to ARDS. Although there was no difference in progression to ARDS, 28-day mortality was higher in the intervention group. Notably, the mean overall driving pressure across both groups was low (12.02 mbar ± 2.77).

CONCLUSIONS

In a population at risk of ARDS, a combined intervention of a clinical decision support system and a nudge intervention was shown to reduce the excessive driving pressure above 15 mbar in augmented but not in controlled modes of ventilation.

Impacts of initial ICU driving pressure on outcomes in acute hypoxemic respiratory failure: a MIMIC-IV database study

Driving pressure (DP) is a marker of severity of lung injury in patients with acute respiratory distress syndrome (ARDS) and has a strong association with outcome. However, it is uncertain whether limiting DP can reduce the mortality of patients with acute hypoxemic respiratory failure (AHRF). Therefore, this study aimed to determine the correlation between the initial DP setting and the clinical outcomes of patients with AHRF upon their initial admission to the intensive care unit (ICU). The Medical Information Mart for Intensive Care IV (MIMIC-IV) database was used to search the data of patients with AHRF, with 180-day mortality representing the primary outcome. Multiple regression analysis was subsequently performed to evaluate the initial DP and 180-day mortality association. The reliability of the results was validated using restricted cubic splines and interaction studies. This study retrospectively analyzed data from 907 patients-581 (64.06%) in the survival group and 326 (35.94%) in the nonsurvival group (NSG)-who were followed up 180 days after admission. The results revealed that an elevated initial DP was significantly correlated with 180-day mortality (HR 1.071 (95% CI 1.040, 1.102)), especially when the initial DP exceeded 12 cmH2O. AHRF patients with an initial DP > 12 cmH2O had significantly greater mortality at 28 days (p = 0.0082), 90 days (p = 0.0083), and 180 days (p = 0.0039) than those with an initial DP ≤ 12 cmH2O. Among severe patients with AHRF, 180-day mortality was significantly greater in the group with an initial DP > 12 cmH2O than in the group with an initial DP ≤ 12 cmH2O (p = 0.029). The hospital length of stay (LOS) for patients with an initial DP < 12 cmH2O was significantly longer than that for those with an initial DP > 12 cmH2O (p = 0.029). Among patients with AHRF and an initial DP > 12 cmH2O, the survival group had a significantly longer LOS in the ICU than the NSG (p = 0.00026). The initial DP settings were correlated with 180-day mortality among patients with AHRF admitted to the ICU. Particularly for patients with AHRF, it is crucial to consider implementing early restrictive DP ventilation as a potential means to mitigate mortality, and close monitoring is essential to evaluate its impact.

Driving pressure: A useful tool for reducing postoperative pulmonary complications

The operating room is a unique environment where surgery exposes patients to non-physiological changes that can compromise lung mechanics. Therefore, raising clinicians' awareness of the potential risk of ventilator-induced lung injury (VILI) is mandatory. Driving pressure is a useful tool for reducing lung complications in patients with acute respiratory distress syndrome and those undergoing elective surgery. Driving pressure has been most extensively studied in the context of single-lung ventilation during thoracic surgery. However, the awareness of association of VILI risk and patient positioning (prone, beach-chair, park-bench) and type of surgery must be raised.

Driving pressure decoded: Precision strategies in adult respiratory distress syndrome management

Mechanical ventilation (MV) is an important strategy for improving the survival of patients with respiratory failure. However, MV is associated with aggravation of lung injury, with ventilator-induced lung injury (VILI) becoming a major concern. Thus, ventilation protection strategies have been developed to minimize complications from MV, with the goal of relieving excessive breathing workload, improving gas exchange, and minimizing VILI. By opting for lower tidal volumes, clinicians seek to strike a balance between providing adequate ventilation to support gas exchange and preventing overdistension of the alveoli, which can contribute to lung injury. Additionally, other factors play a role in optimizing lung protection during MV, including adequate positive end-expiratory pressure levels, to maintain alveolar recruitment and prevent atelectasis as well as careful consideration of plateau pressures to avoid excessive stress on the lung parenchyma.