Automated vs. conventional ventilation in the ICU: a randomized controlled crossover trial comparing blood oxygen saturation during daily nursing procedures (I-NURSING).

BACKGROUND: Hypoxia is common during daily nursing procedures (DNPs) routinely performed on mechanically ventilated patients. The impact of automated ventilation on the incidence and severity of blood oxygen desaturation during DNPs remains unknown. METHODS: A prospective randomized controlled crossover trial was carried out in a French intensive care unit to compare blood oxygen pulse saturation (SpO2) during DNPs performed on patients mechanically ventilated in automated and conventional ventilation modes (AV and CV, respectively). All patients with FiO2 ≤ 60% and without prone positioning or neuromuscular blocking agents were included. Patients underwent two DNPs on the same day using AV (INTELLiVENT-ASV®) and CV (volume control, biphasic positive airway pressure, or pressure support ventilation) in a randomized order. The primary outcome was the percentage of time spent with SpO2 in the acceptable range of 90-95% during the DNP. RESULTS: Of the 265 included patients, 93% had been admitted for a medical pathology, the majority for acute respiratory failure (52%). There was no difference between the two periods in terms of DNP duration, sedation requirements, or ventilation parameters, but patients had more spontaneous breaths and lower peak airway pressures during the AV period (p <  0.001). The percentage of time spent with SpO2 in the acceptable range during DNPs was longer in the AV period than in the CV period (48 ± 37 vs. 43 ± 37, percentage of DNP period; p = 0.03). After adjustment, AV was associated with a higher number of DNPs carried out with SpO2 in the acceptable range (odds ratio, 1.82; 95% CI, 1.28 to 2.6; p = 0.001) and a lower incidence of blood oxygen desaturation ≤ 85% (adjusted odds ratio, 0.50; 95% CI, 0.30 to 0.85; p = 0.01). CONCLUSION: AV appears to reduce the incidence and severity of blood oxygen desaturation during daily nursing procedures (DNPs) in comparison to CV. TRIAL REGISTRATION: This study was registered in clinical-trial.gov ( NCT03176329 ) in June 2017.

Efficiency of goal-directed oxygen delivery in ICU patients.

BACKGROUND: Current clinical practice guidelines promote a goal-directed approach for oxygen delivery with respect to SpO2 objectives. We evaluated the efficiency of a strategy based on goal-directed O2 delivery in the ICU. METHODS: A group of 30 patients (Group 1) with a proven history of chronic obstructive pulmonary disease suffering from acute hypercarbic exacerbation was compared to 2 other groups of patients admitted for acute respiratory failure with no history of pulmonary disease: 30 patients requiring oxygen supply and/or non-invasive ventilation (Group 2) and 30 requiring invasive ventilation (Group 3). The delivery of oxygen was based on SpO2 measurement: 88-94% for Group 1 and 90-96% for others. The time spent with an SpO2 below, within and above the prescribed limits was collected. RESULTS: The mean time spent within the prescribed range was for Groups 1, 2 and 3, respectively as follows: 61.9% [60.5-63.2], 63.7% [62.3-65] and 56.4% [55.3-57.6] (P < 0.001 for each group). A history of chronic obstructive pulmonary disease was not correlated with better results (P = 0.11), while invasive ventilation was related to the time spent out of the prescribed range (P < 0.001; OR 1.3 [1.22-1.28]) especially in hyperoxaemia (40.7% [39.6-41.8] P < 0.001). Efficiency seems unrelated to nursing workload or night team exhaustion (r = -0.09, P = 0.77). CONCLUSIONS: Goal-directed oxygen delivery based on SpO2 objectives in ICU patients ensures that in only approximately 64% of the time, SpO2 stays within the prescribed range.