Ventilatory Failure

To determine the quality of life of patients living with chronic respiratory failure and the impact interventions have on it.

The goal of this observational study is to assess the potential non-invasive tools (e.g. regional ventilation, respiratory muscle response, lung mechanic's parameters) to identify the risk of failure when using high flow nasal cannula (HFNC) or non-invasive ventilation (NIV). The main question, it aims to answer is: Does abnormal regional ventilation could predict HFNC or NIV failure?

Little is known about how lung mechanics are affected during the very early phase after starting mechanical ventilation. Since the conventional method of measuring esophageal pressure is complicated, hard to interpret and expensive, there are no studies on lung mechanics on intensive care patients directly after intubation, during the first hours of ventilator treatment and forward until the ventilator treatment is withdrawn. Published studies have collected data using the standard methods from day 1 to 3 of ventilator treatment for respiratory system mechanics, i.e. the combined mechanics of lung and chest wall. Consequently, information on lung mechanical properties during the first critical hours of ventilator treatment is missing and individualization of ventilator care done on the basis of respiratory system mechanics, which are not representative of lung mechanics on an individual patient basis. We have developed a PEEP-step method based on a change of PEEP up and down in one or two steps, where the change in end-expiratory lung volume ΔEELV) is determined and lung compliance calculated as ΔEELV divided by ΔPEEP (CL = ΔEELV/ΔPEEP). This simple non-invasive method for separating lung and chest wall mechanics provides an opportunity to enhance the knowledge of lung compliance and the transpulmonary pressure. After the two-PEEP-step procedure, the PEEP level where transpulmonary driving pressure is lowest can be calculated for any chosen tidal volume. The aim of the present study in the ICU is to survey lung mechanics from start of mechanical ventilation until extubation and to determine PEEP level with lowest (least injurious) transpulmonary driving pressure during ventilator treatment. The aim of the study during anesthesia in the OR, is to survey lung mechanics in lung healthy and identify patients with lung conditions before anesthesia, which may have an increased risk of postoperative complications.

The objective of this study is to compare the accuracy and correlation of the capnodynamic method for measuring mixed venous oxygen saturation (SvO2) with the standard reference method (pulmonary artery catheter), with the potential for the capnodynamic method to replace the traditional method in selected cases.