Effectiveness of Helmet-CPAP in mild to moderate coronavirus type 2 hypoxemia: An observational study.

OBJECTIVE: To determine the relative effectiveness of Helmet-CPAP (H_CPAP) with respect to high-flow nasal cannula oxygen therapy (HFNO) in avoiding greater need for intubation or mortality in a medium complexity hospital in Chile during the year 2021. DESIGN: Cohort analytical study, single center. SETTING: Units other than intensive care units. PATIENTS: Records of adults with mild to moderate hypoxemia due to coronavirus type 2. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Need for intubation or mortality. RESULTS: 159 patients were included in the study, with a ratio by support of 2:10 (H_CPAP:HFNO). The 46.5% were women, with no significant differences by sex according to support (p = 0.99, Fisher test). The APACHE II score, for HFNO, had a median of 10.5, 3.5 units higher than H_CPAP (p < 0.01, Wilcoxon rank sum). The risk of intubation in HFNO was 42.1% and in H_CPAP 3.8%, with a significant risk reduction of 91% (95% CI: 36.9%-98.7%; p < 0.01). APACHE II does not modify or confound the support and intubation relationship (p > 0.2, binomial regression); however, it does confound the support and mortality relationship (p = 0.82, RR homogeneity test). Despite a 79.1% reduction in mortality risk with H_CPAP, this reduction was not statistically significant (p = 0.11, binomial regression). CONCLUSIONS: The use of Helmet CPAP, when compared to HFNO, was an effective therapeutic ventilatory support strategy to reduce the risk of intubation in patients with mild to moderate hypoxemia caused by coronavirus type 2 in inpatient units other than intensive care. The limitations associated with the difference in size, age and severity between the arms could generate bias.

Comprehensive study of mechanical power in controlled mechanical ventilation: Prevalence of elevated mechanical power and component analysis / Estudio Integral de la Potencia Mecánica en la Ventilación Mecánica Controlada: Prevalencia de Potencia Mecánica Elevada y Análisis de Componentes

Objective To determine the prevalence of elevated mechanical power (MP) values (>17J/min) used in routine clinical practice. Design Observational, descriptive, cross-sectional, analytical, multicenter, international study conducted on November 21, 2019, from 8:00 AM to 3:00 PM. NCT03936231. Setting One hundred thirty-three Critical Care Units. Patients Patients receiving invasive mechanical ventilation for any cause. Interventions None. Main variables of interest Mechanical power. Results A population of 372 patients was analyzed. PM was significantly higher in patients under pressure-controlled ventilation (PC) compared to volume-controlled ventilation (VC) (19.20±8.44J/min vs. 16.01±6.88J/min; p<0.001), but the percentage of patients with PM>17J/min was not different (41% vs. 35%, respectively; p=0.382). The best models according to AICcw expressing PM for patients in VC are described as follows: Surrogate Strain (Driving Pressure) + PEEP+Surrogate Strain Rate (PEEP/Flow Ratio) + Respiratory Rate. For patients in PC, it is defined as: Surrogate Strain (Expiratory Tidal Volume/PEEP) + PEEP+Surrogate Strain Rate (Surrogate Strain/Ti) + Respiratory Rate+Expiratory Tidal Volume+Ti. Conclusions A substantial proportion of mechanically ventilated patients may be at risk of experiencing elevated levels of mechanical power. Despite observed differences in mechanical power values between VC and PC ventilation, they did not result in a significant disparity in the prevalence of high mechanical power values. (AU)

Objetivo Determinar la prevalencia de valores elevados de potencia mecánica (PM) (>17J/min) utilizados en la práctica clínica habitual. Diseño estudio observacional, descriptivo de corte transversal, analítico, multicéntrico e internacional, realizado el 21 de noviembre de 2019 en horario de 8 a 15 horas. NCT03936231. Ámbito Ciento treinta y tres Unidad de Cuidados Críticos. Pacientes pacientes que recibirán ventilación mecánica por cualquier causa. Intervenciones ninguna Variables de interés principales Potencia mecánica. Resultados se analizaron 372 enfermos. La PM fue significativamente mayor en pacientes en ventilación controlada por presión (PC) que en ventilación controlada por volumen (VC) (19,20+8,44J/min frente a 16,01+6,88J/min; p<0,001), pero el porcentaje de pacientes con PM>17J/min no fue diferente (41% frente a 35% respectivamente; p=0,382). Los mejores modelos según AICcw que expresan la PM para los enfermos en VC se decribe como: Strain subrogante (Presión de conducción) + PEEP+Strain Rate subrogante (PEEP/cociente de flujo) + Frecuencia respiratoria. Para los enfermos en PC se define como: Strain subrogante (Volumen tidal expiratorio/PEEP) + PEEP+Strain Rate subrogante (Strain subrogante/Ti) + Frecuencia respiratoria+Expiratory Tidal Volumen+Ti. Conclusiones Gran parte de los pacientes en ventilación mecánica en condiciones de práctica clínica habitual reciben niveles de potencia mecánica peligrosos. A pesar de las diferencias observadas en los valores de potencia mecánica entre la ventilación VC y PC, este porcentaje de riesgo fue similar en PC y VC. (AU)

Comprehensive study of mechanical power in controlled mechanical ventilation: Prevalence of elevated mechanical power and component analysis.

OBJECTIVE: To determine the prevalence of elevated mechanical power (MP) values (>17J/min) used in routine clinical practice. DESIGN: Observational, descriptive, cross-sectional, analytical, multicenter, international study conducted on November 21, 2019, from 8:00 AM to 3:00 PM. NCT03936231. SETTING: One hundred thirty-three Critical Care Units. PATIENTS: Patients receiving invasive mechanical ventilation for any cause. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Mechanical power. RESULTS: A population of 372 patients was analyzed. PM was significantly higher in patients under pressure-controlled ventilation (PC) compared to volume-controlled ventilation (VC) (19.20±8.44J/min vs. 16.01±6.88J/min; p<0.001), but the percentage of patients with PM>17J/min was not different (41% vs. 35%, respectively; p=0.382). The best models according to AICcw expressing PM for patients in VC are described as follows: Surrogate Strain (Driving Pressure) + PEEP+Surrogate Strain Rate (PEEP/Flow Ratio) + Respiratory Rate. For patients in PC, it is defined as: Surrogate Strain (Expiratory Tidal Volume/PEEP) + PEEP+Surrogate Strain Rate (Surrogate Strain/Ti) + Respiratory Rate+Expiratory Tidal Volume+Ti. CONCLUSIONS: A substantial proportion of mechanically ventilated patients may be at risk of experiencing elevated levels of mechanical power. Despite observed differences in mechanical power values between VC and PC ventilation, they did not result in a significant disparity in the prevalence of high mechanical power values.