Institute for Continuing Education

Mechanical Ventilation

Course Objectives

Upon successful completion of this module, you will be able to:

• Module 1: Foundations, Physiology, and Indications
  • Explain the physiological basis of positive pressure ventilation including effects on respiratory mechanics, gas exchange, acid-base balance, and cardiovascular function.
  • Apply the equation of motion for the respiratory system to interpret measured airway pressures and calculate static compliance, dynamic compliance, and airway resistance.
  • Identify and classify the clinical indications for initiating mechanical ventilation including hypoxemic failure, hypercapnic failure, airway protection, and excessive work of breathing.
  • Describe the systematic approach to pre-intubation assessment, patient preparation, and early post-intubation management.
• Module 2: Ventilator Modes and Lung-Protective Settings
  • Classify mechanical ventilation modes by control variable, breath sequence, and targeting scheme, and select appropriate modes for specific clinical scenarios.
  • Compare volume-controlled and pressure-controlled ventilation regarding breath delivery characteristics, advantages, limitations, and monitoring requirements.
  • Calculate predicted body weight from height and apply lung-protective ventilation targets for tidal volume, plateau pressure, and driving pressure.
  • Implement PEEP titration strategies using the ARDSNet PEEP-FiO2 tables and explain the physiological rationale for each approach.
• Module 3: Monitoring, Waveform Analysis, and Complications
  • Interpret pressure-time, flow-time, and volume-time waveforms to assess respiratory mechanics, identify patient-ventilator asynchrony, and guide ventilator adjustments.
  • Identify and correct the six major types of patient-ventilator asynchrony by analyzing waveform characteristics and applying targeted interventions.
  • Recognize the mechanisms of ventilator-induced lung injury and implement prevention strategies including lung-protective ventilation parameters.
  • Describe the pathogenesis of ventilator-associated pneumonia and implement the evidence-based prevention bundle.
• Module 4: Liberation, NIV, and Special Populations
  • Apply a systematic daily protocol for mechanical ventilation liberation including readiness criteria, spontaneous awakening trials, and spontaneous breathing trials.
  • Interpret spontaneous breathing trial results using the RSBI and other clinical parameters to guide extubation decisions.
  • Select and implement noninvasive ventilation and high-flow nasal cannula therapy for appropriate patients and monitor for treatment success or failure.
  • Adapt ventilator strategies for patients with obstructive lung disease, neuromuscular disease, acute brain injury, and morbid obesity.
• Module 5: Quality, Advanced ARDS, and Clinical Integration
  • Apply the ABCDEF bundle and describe the evidence supporting each component for reducing ventilator-associated complications.
  • Describe the escalating interventions for severe refractory ARDS including prone positioning, inhaled vasodilators, neuromuscular blockade, and ECMO.
  • Integrate course content to develop and execute comprehensive ventilator management plans for complex patient scenarios using a four-phase clinical decision-making framework.
  • Identify the domains of post-intensive care syndrome and describe prevention strategies available to the respiratory therapist.

Course Information

Respiratory failure is caused by failure to ventilate, characterized by increased arterial carbon dioxide tension, or failure to oxygenate, characterized by decreased arterial oxygen tension. The treatment for failure to ventilate is to increase the patient?s alveolar ventilation, that is the rate and depth of breathing, either by reversing the cause or by using mechanical ventilation; invasively or non-invasively.

Failure to oxygenate may occur as a result of decreased alveolar oxygen tension (due to decreased inspired O2 tension or increased CO2 tension), reduced O2 diffusion capacity (due to interstitial edema or fibrosis, or thickened alveolar walls) or ventilation perfusion mismatch (due to loss of functional residual capacity and alveolar collapse/consolidation). The treatment for failure to oxygenate is restoration and maintenance of lung volumes, using recruitment maneuvers and increased baseline airway pressures (PEEP/CPAP). Imposed ventilatory workload is increased by loss of lung compliance and inspiration/ventilation is usually supported to reduce O2 requirements and increase patient comfort.

Modes of ventilation describe the primary method of inspiratory assistance. A machine generates and regulates the flow of gas into the lungs, flow continues until a predetermined volume has been delivered or airway pressure generated. Flow reverses, when the machine cycles into the expiratory phase. The message to do this is either at preset time, preset tidal volume or a preset percentage of peak flow. Mechanical breaths may be controlled (the ventilator is active and the patient passive) or assisted (the patient initiates and may or may not participate in the breath).

Large tidal volumes overstretch alveoli and injure the lung. Small tidal volumes increase the contribution to minute ventilation of dead space. The science of mechanical ventilation is to optimize pulmonary gas exchange; the art is to achieve this without damaging the lungs.

Many healthcare providers are usually baffled by the variety of different ventilatory modes, and the fortitude of others in arguing the relative merits of one over another. In truth, there is little evidence that there is an ideal mode of ventilation. Remember, for any patient, it is the same (see setting ?ideal level of PEEP? below) that we are pushing the patient up, what differs is the way in which gas flow achieves this. In this course, we have added graphics of screen captures from mechanically ventilated patients, so that you may begin to appreciate this interaction of flow, airway pressure and delivered volume.