The aim of this prospective physiological cohort study conducted in a medical intensive care unit (ICU) at Hospital del Mar in Barcelona, Spain, was to analyze the proportion of time spent within the "safe" range of respiratory effort (including esophageal pressure swing (ΔPes), respiratory muscular pressure (Pmus), and transdiaphragmatic pressure swing (ΔPdi)) in patients with acute hypoxemic respiratory failure (AHRF) undergoing invasive mechanical ventilation (IMV), during the active breathing phase in relation to ICU survival. The investigators hypothesized that AHRF patients on IMV with better outcome (i.e., ICU survivors) spend more time within the "safe" range of respiratory effort during the active breathing phase compared to non-survivors. AHRF patients on IMV were continuously monitored with esophageal and gastric manometry from the detection of the onset of respiratory effort for up to 7 days, or until extubation, or until death, whichever occurred first.
To characterize in detail the evolution of respiratory effort over time, the investigators conducted a prospective observational cohort study with continuous recordings of airway pressure, flow, esophageal and gastric pressures for up to 7 days after the onset of respiratory effort in AHRF patients on IMV. Patients were classified into two groups: ICU survivors and ICU non-survivors. The primary objective of the study was to analyze the proportion of time spent within a specified "safe" range for Pmus, ΔPes, and ΔPdi (respiratory effort physiological variables), during spontaneous breathing, comparing both groups during the first 7 days after the initiation of respiratory effort. The secondary objective was to analyze the median values of ΔPes, Pmus, and ΔPdi during the monitorization period (active breathing phase) between the two groups.
Study Type
OBSERVATIONAL
Enrollment
31
Hospital del Mar
Barcelona, Catalonia, Spain
Proportion of time spent in different ranges of ΔPes (low, safe, and high) during the active breathing phase between the two groups
The defined "safe" range for ΔPes was -5 to -10 cm H2O. Effort outside the defined "safe" range was categorized as "low" if it fell below the lower limit, or "high" if it exceeded the upper limit of the safe range for the variable.
Time frame: From the start the start of respiratory effort up to 7 days (or until extubation or death, if earlier)
Proportion of time spent in different ranges of Pmus (low, safe, and high) during the active breathing phase between the two groups
The defined "safe" range for Pmus was 5 to 15 cm H2O. Effort outside the defined "safe" range was categorized as "low" if it fell below the lower limit, or "high" if it exceeded the upper limit of the safe range for the variable.
Time frame: From the start the start of respiratory effort up to 7 days (or until extubation or death, if earlier)
Proportion of time spent in different ranges of ΔPdi (low, safe, and high) during the active breathing phase between the two groups
The defined "safe" range for ΔPdi was 3 to 12 cm H2O. Effort outside the defined "safe" range was categorized as "low" if it fell below the lower limit, or "high" if it exceeded the upper limit of the safe range for the variable.
Time frame: From the start the start of respiratory effort up to 7 days (or until extubation or death, if earlier)
Median value of ΔPes during the active breathing phase between the two groups
To analyze the median value of ΔPes during the active breathing phase between the two groups in cm H20.
Time frame: From the start the start of respiratory effort up to 7 days (or until extubation or death, if earlier)
Median value of Pmus during the active breathing phase between the two groups
To analyze the median value of Pmus during the active breathing phase between the two groups in cm H20.
Time frame: From the start the start of respiratory effort up to 7 days (or until extubation or death, if earlier)
Median value of ΔPdi during the active breathing phase between the two groups
To analyze the median value of ΔPdi during the active breathing phase between the two groups in cm H20.
Time frame: From the start the start of respiratory effort up to 7 days (or until extubation or death, if earlier)
The need for the use of venovenous (VV) extracorporeal membrane oxygenation (ECMO)
Initiation of VV ECMO during the mechanical ventilation period (yes or no)
Time frame: From date of initiation of invasive mechanical ventilation until extubation or date of death from any cause, whichever came first, assessed up to 24 months
The need for the use of extracorporeal CO2 removal (ECCO2R)
Initiation of ECCO2R during the mechanical ventilation period (yes or no)
Time frame: From date of initiation of invasive mechanical ventilation until extubation or date of death from any cause, whichever came first, assessed up to 24 months
The need for a Tracheostomy
The need to perfom a tracheostomy duduring the mechanical ventilation period (yes or no)
Time frame: From date of initiation of invasive mechanical ventilation until extubation or date of death from any cause, whichever came first, assessed up to 24 months
Duration of invasive mechanical ventilation (IMV)
Duration of IMV measured in days
Time frame: From date of initiation of invasive mechanical ventilation until extubation or date of death from any cause, whichever came first, assessed up to 24 months
Intensive care Unit (ICU) Length of stay
Duration of the ICU admission measured in days
Time frame: From date of ICU admission until date of ICU discharge or date of death from any cause, whichever came first, assessed up to 24 months
Hospital Length of stay
Duration of the Hospital admission measured in days
Time frame: From date of Hospital admission until date of Hospital discharge or date of death from any cause, whichever came first, assessed up to 24 months
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.