Optimization of Positive End-Expiratory Pressure Targeting the Best Arterial Oxygen Transport in the Acute Respiratory Distress Syndrome: The OPTIPEP Study

Methods for determining optimal positive end-expiratory pressure in patients undergoing invasive mechanical ventilation: a scoping review

PURPOSE

There is significant variability in the application of positive end-expiratory pressure (PEEP) in patients undergoing invasive mechanical ventilation. There are numerous studies assessing methods of determining optimal PEEP, but many methods, patient populations, and study settings lack high-quality evidence. Guidelines make no recommendations about the use of a specific method because of equipoise and lack of high-quality evidence. We conducted a scoping review to determine which methods of determining optimal PEEP have been studied and what gaps exist in the literature.

SOURCE

We searched five databases for primary research reports studying methods of determining optimal PEEP among adults undergoing invasive mechanical ventilation. Data abstracted consisted of the titration method, setting, study design, population, and outcomes.

PRINCIPLE FINDINGS

Two hundred and seventy-one studies with 17,205 patients met the inclusion criteria, including 73 randomized controlled trials (RCTs) with 10,733 patients. We identified 22 methods. Eleven were studied with an RCT. Studies enrolled participants within an intensive care unit (ICU) (216/271, 80%) or operating room (55/271, 20%). Most ICU studies enrolled patients with acute respiratory distress syndrome (162/216, 75%). The three most studied methods were compliance (73 studies, 29 RCTs), imaging-based methods (65 studies, 11 RCTs), and use of PEEP-FIO2 tables (52 studies, 20 RCTs). Among ICU RCTs, the most common primary outcomes were mortality or oxygenation. Few RCTs assessed feasibility of different methods (n = 3). The strengths and limitations of each method are discussed.

CONCLUSION

Numerous methods of determining optimal PEEP have been evaluated; however, notable gaps remain in the evidence supporting their use. These include specific populations (normal lungs, patients weaning from mechanical ventilation) and using alternate outcomes (ventilator-free days and feasibility) and they present significant opportunities for future study.

STUDY REGISTRATION

Open Science Framework ( https://osf.io/atzqc ); first posted, 19 July 2022.

Implementation of a Goal-Directed Mechanical Ventilation Order Set Driven by Respiratory Therapists Improves Compliance With Best Practices for Mechanical Ventilation

PURPOSE

Data regarding best practices for ventilator management strategies that improve outcomes in acute respiratory distress syndrome (ARDS) are readily available. However, little is known regarding processes to ensure compliance with these strategies. We developed a goal-directed mechanical ventilation order set that included physician-specified lung-protective ventilation and oxygenation goals to be implemented by respiratory therapists (RTs). We sought as a primary outcome to determine whether an RT-driven order set with predefined oxygenation and ventilation goals could be implemented and associated with improved adherence with best practice.

METHODS

We evaluated 1302 patients undergoing invasive mechanical ventilation (1693 separate episodes of invasive mechanical ventilation) prior to and after institution of a standardized, goal-directed mechanical ventilation order set using a controlled before-and-after study design. Patient-specific goals for oxygenation partial pressure of oxygen in arterial blood (Pao ₂), ARDS Network [Net] positive end-expiratory pressure [PEEP]/fraction of inspired oxygen [Fio ₂] table use) and ventilation (pH, partial pressure of carbon dioxide) were selected by prescribers and implemented by RTs.

RESULTS

Compliance with the new mechanical ventilation order set was high: 88.2% compliance versus 3.8% before implementation of the order set ( P < .001). Adherence to the PEEP/Fio ₂ table after implementation of the order set was significantly greater (86.0% after vs 82.9% before, P = .02). There was no difference in duration of mechanical ventilation, intensive care unit (ICU) length of stay, and in-hospital or ICU mortality.

CONCLUSIONS

A standardized best practice mechanical ventilation order set can be implemented by a multidisciplinary team and is associated with improved compliance to written orders and adherence to the ARDSNet PEEP/Fio ₂ table.