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BACKGROUND: Current mechanical ventilation practice and the use of treatment adjuncts in patients requiring extracorporeal membrane oxygenation (ECMO) for refractory hypoxemia (RH) vary widely and their impact on outcomes remains unclear. In 2015, we implemented a standardized approach to protocolized ventilator settings and guide the escalation of adjunct therapies in patients with RH. This study aimed to investigate ICU mortality, its associated risk factors, and mechanical ventilation practice before and after the implementation of a standardized RH guideline in patients requiring venovenous ECMO (VV-ECMO). METHODS: This was a single-center, retrospective cohort study of patients undergoing VV-ECMO due to RH respiratory failure between January 2008 and March 2015 (before RH protocol implementation) and between April 2015 and October 2019 (after RH protocol implementation). RESULTS: A total of 103 subjects receiving VV-ECMO for RH were analyzed. After implementation of the RH protocol, more subjects received prone positioning (6.7% vs 23.3%, P = .02), and fewer received high-frequency oscillatory ventilation than before launching the RH protocol (0% vs 13.3%, P = .01). Plateau pressure was also lower before initiation of ECMO (P = .04) and at day 1 during ECMO (P = .045). Driving pressure was consistently lower at days 1, 2, and 3 after ECMO initiation: median 13.0 (interquartile range [IQR] 10.6–18.0) vs 16.0 (IQR 14.0–20.0) cm H2O at day 1 (P = .003); 13.0 (IQR 11.0–15.9) vs 15.5 (IQR 12.0–20.0) cm H2O at day 2 (P = .03); and 12.0 (IQR 10.0–14.5) vs 15.0 (IQR 12.0–19.0) cm H2O at day 3 (P = .005). CONCLUSIONS: The implementation of a standardized RH guideline improved compliance with a lung-protective ventilation strategy and utilization of the prone position and was associated with lower driving pressure during the first 3 days after ECMO initiation in subjects with refractory hypoxemia.

BACKGROUND: ARDS remains a source of significant morbidity and mortality in the critically ill patient. The mainstay of therapy entails invasive mechanical ventilation utilizing a lung-protective strategy designed to limit lung injury associated with excessive stress and strain while the underlying etiology of respiratory failure is identified and treated. Less is understood about what to do once conventional ventilation parameters have been optimized but the patient’s respiratory status remains unchanged or worsens. In 2015, a protocolized, stepwise approach to mechanical ventilation with partially automated and clearly defined thresholds for management changes was implemented at our institution. We hypothesized that, by identifying appropriate patients earlier, time-to-escalation and rescue therapy implementation would be shortened. METHODS: Subjects with severe ARDS, treated with prone positioning based on our institution’s protocolized approach from December 2013 to August 2016 were included. Their baseline characteristics, severity of illness scores, and mechanical ventilation parameters were collected and analyzed. RESULTS: Baseline characteristics, tidal volumes, PaO2/FIO2, duration of ventilation after proning, and mortality were similar in both groups. Median (interquartile range [IQR]) PEEP at the time of proning was higher after the protocol implementation (12.5 cm H2O [IQR 6.5–19.4] vs 18 cm H2O [IQR 10–22], P = .386), and mean (IQR) respiratory system driving pressure was lower (16 cm H2O [IQR 13–36.2] vs 12 cm H2O [IQR 9–19.6], P = .029). Median (IQR) time from refractory hypoxemia identification to proning was shorter after protocol implementation (42.2 h [IQR 6.83–347.2] vs 16.3 h [IQR 1–99.7], I = .02), and PaO2/FIO2 at 1 h after proning was higher. ICU and hospital LOS were shorter after the protocol implementation. CONCLUSIONS: Following the implementation of an early, evidence-based, protocolized approach to optimizing mechanical ventilation, subjects with true refractory hypoxemia were identified earlier and time to proning was significantly shorter. Despite improvement in the evaluation and management of refractory hypoxemia as well as time to initiation of prone positioning, mortality was unchanged and there was variation in the duration of the position.

BACKGROUND: Liberal oxygenation during mechanical ventilation is harmful in critically ill patients and in certain subsets of patients, including those with stroke, acute myocardial infarction, and cardiac arrest. Surveillance through electronic medical records improves safety of mechanical ventilation in the ICU. To date, this practice has not been used for oxygen titration ([Formula: see text]) in adults. We hypothesize that a surveillance system based on the electronic medical record to alert respiratory therapists to titrate [Formula: see text] is feasible, safe, and efficacious. METHODS: In this pilot study, mechanically ventilated subjects were randomized to respiratory therapist-driven [Formula: see text] titration after an electronic alert versus standard of care (ie, titration based on physician order). An automated surveillance system utilizing a hyperoxemia-detection algorithm generated an electronic alert to a respiratory therapist’s pager. Hyperoxemia was defined as [Formula: see text] > 0.5 and [Formula: see text] > 95% for > 30 min. No other aspects of treatment were changed. We assessed feasibility, safety, and preliminary efficacy. Primary outcome was duration of hyperoxemia during mechanical ventilation. An unsafe outcome was identified as hypoxemia ([Formula: see text] < 88%) within 1 h after titration per alert. Feasibility was assessed by a survey of respiratory therapists. RESULTS: Of 226 randomized subjects, 31 were excluded (eg, programming errors of the electronic alerts, no consent, physician discretion). We included 195 subjects, of whom 86 were in the intervention arm. Alert accuracy was 78%, and respiratory therapists responded to 64% of the alerts. During mechanical ventilation, exposure to hyperoxemia significantly decreased in the intervention group (median 13.5 h [interquartile range 6.2–29.4] vs 18.8 h [interquartile range 9.6–37.4]). No episodes of significant hypoxemia were registered. Most respiratory therapists agreed that the alert was helpful in reducing excessive oxygen exposure. CONCLUSIONS: Use of an electronic surveillance system to titrate [Formula: see text] was safe and feasible and showed preliminary efficacy in reducing hyperoxemia. Our study serves to justify larger randomized controlled trials for [Formula: see text] titration.

Weaning from mechanical ventilation involves the reduction or withdrawal of ventilatory support in proportion to the patient's ability to sustain spontaneous ventilation. Protocolized weaning has been shown to reduce weaning duration; however, its weakness lies in the reliance on human intervention. Automated weaning is theoretically superior to manual weaning because of its ability to rapidly recognize deviations from desired behavior and enforce compliance with a standardized weaning strategy unencumbered by external influences. Whether currently available methods for automated weaning fulfill that potential to achieve superiority depends on patient type, care environment, and cause of ventilator dependence.

BACKGROUND: Patients with do-not-intubate (DNI) status and respiratory failure are commonly treated with noninvasive ventilation (NIV). High-flow nasal cannula (HFNC) therapy supplies a high flow of heated and humidified oxygen that may provide an effective alternative to NIV. We assessed the efficacy of HFNC in DNI patients with hypoxemic respiratory distress. METHODS: We identified 50 DNI patients with hypoxemic respiratory distress who were admitted to a medical ICU and who received HFNC. We excluded patients with PaCO2 > 65 mm Hg and pH < 7.28. The primary end point was the need for escalation to NIV, as determined by the primary service. Mean changes in oxygen saturation and breathing frequency before and after HFNC were compared. RESULTS: The subjects included 25 men and 25 women, mean age 73 years (range 27–96 y). Diagnoses (allowing multiple conditions) included pulmonary fibrosis (15), pneumonia (15), COPD (12), cancer (7), hematologic malignancy (7), and congestive heart failure (3). Hospital mortality was 60% (30/50). HFNC was initiated at a mean FIO2 of 0.67 (range 0.30–1.0) and flow of 42.6 L/min (range 30–60 L/min). Mean O2 saturations went from 89.1% to 94.7% ( P < .001), and breathing frequency went from 30.6 breaths/min to 24.7 breaths/min ( P < .001). Nine of the 50 subjects (18%) escalated to NIV, while 82% were maintained on HFNC. The median duration of HFNC was 30 hours (range 2–144 h). CONCLUSIONS: HFNC can provide adequate oxygenation for many patients with hypoxemic respiratory failure and may be an alternative to NIV for DNI patients.

Movement of the mechanically ventilated patient may be for a routine procedure or medical emergency. The risks of transport seem manageable, but the memory of a respiratory-related catastrophe still gives many practitioners pause. The risk/benefit ratio of transport must be assessed before movement. During transport of the ventilated patients, should we always use a transport ventilator? What is the risk of using manual ventilation? How are PEEP and FIO2 altered? Is there an impact on the ability to trigger during manual ventilation? Is hyperventilation and hypoventilation a common problem? Does hyperventilation or hypoventilation result in complications? Are portable ventilators worth the cost? What about the function of portable ventilators? Can these devices faithfully reproduce ICU ventilator function? The following pro and con discussion will attempt to address many of these issues by reviewing the current evidence on transport ventilation.