Mechanical Ventilation Overview

Introduction to Mechanical Ventilation

• Purpose: Life-saving intervention for patients unable to breathe on their own.
• Function: Uses positive pressure to deliver oxygenated air into the lungs for gas exchange.
• Complexity: Essential knowledge for respiratory therapists and medical professionals.
• Objective: Provide comprehensive overview of mechanical ventilation and ventilator basics.

Indications for Mechanical Ventilation

• Insufficient Oxygenation: Affects tissue and organ functionality; ventilation delivers necessary oxygen.
• Insufficient Ventilation: Leads to blood acidity; helps remove CO2 during exhalation.
• Acute Lung Injury: Causes include sepsis, pneumonia, severe asthma.
• Severe Hypotension: Conditions like shock, sepsis, CHF may require support.
• Airway Protection: Prevent aspiration in airway obstructions like epiglottitis, edema.
• General Indication: Inadequate spontaneous breathing to sustain life.

Contraindications

• No True Contraindications: Ventilation is essential for survival without adequate breathing.
• DNR Orders: Patient wishes not to receive life-saving interventions respected.

Principles of Mechanical Ventilation

• Ventilation: Moving air into and out of lungs.
• Oxygenation: Absorbing oxygen into bloodstream.
• Lung Compliance: Ability to expand and contract.
• Airway Resistance: Impedance of airflow.
• Dead Space Ventilation: Ventilated air not involved in gas exchange.
• Respiratory Failure: Inability to oxygenate blood or remove CO2.

Mechanical Ventilator Basics

• Operation: Uses positive pressure for breathing assistance.
• Intubation: Inserting an artificial airway (endotracheal tube).
• Purpose: Provides support until patient stabilization.

Benefits of Mechanical Ventilation

• Decreases Work of Breathing: Reduces energy expenditure for breathing.
• Maintains Oxygenation: Delivers up to 100% FiO2.
• CO2 Removal: Through increased respiratory rate/tidal volume.
• Stability: Supports patient stability for treatment.

Risks and Complications

• Barotrauma: Lung tissue injury from pressure.
• Ventilator-Associated Pneumonia: Develops after 48+ hours.
• PEEP Complication: Positive pressure remains post-exhalation.
• Oxygen Toxicity: Cell damage from high oxygen levels.
• Ventilator-Induced Lung Injury: Acute lung injury from support.

Types of Mechanical Ventilation

• Positive Pressure: Common, uses pressure greater than atmospheric to push air.
• Negative Pressure: Less common, uses external lower pressure.
• Invasive Ventilation: Through endotracheal or tracheostomy tubes.
• Non-Invasive Ventilation: Uses face mask (e.g., CPAP, BiPAP).

Ventilator Modes

• Volume Control: Fixed volume; pressure varies.
• Pressure Control: Fixed pressure; volume varies.
• Assist Control and SIMV: Common modes; assist control provides full support.

Ventilator Settings

• Mode: Determines ventilator function.
• Tidal Volume: Volume per breath.
• Frequency Rate: Breaths per minute.
• FiO2: Percentage of inspired oxygen.
• PEEP: Positive end-expiratory pressure.

Initiation of Mechanical Ventilation

• Initial Settings: Mode (AC or SIMV), tidal volume (6-8 ml/kg), frequency (10-20/min), FiO2 (30-60%).

Artificial Airways

• Types: Endotracheal tubes, tracheostomy tubes, and alternatives like oropharyngeal airways.

Drugs in Mechanical Ventilation

• Sedatives: Reduce anxiety, maintain interaction.
• Analgesics: Relieve pain.
• Paralytics: Neuromuscular blocking agents.

Managing Ventilated Patients

• Ventilator Management: Adjusting settings, monitoring patient response.
• Monitoring Parameters: Vital signs, blood gases, chest imaging.
• Ventilator Alarms: Alert caregivers to issues.

Troubleshooting and Weaning

• Troubleshooting: Resolve common ventilator problems.
• Weaning: Process of reducing support for independent breathing.
• Extubation: Removing airway tube post-weaning.

Special Considerations

• Neonatal Ventilation: Requires smaller tidal volumes, special for infants.

Conclusion

• Complexity: Essential for respiratory therapists.
• Further Learning: Recommend additional guides and videos for in-depth study.