Ch. 10

Emergency Care: Respiration and Artificial Ventilation

Table of Contents

• Physiology and Pathophysiology

• Mechanics of Breathing
    - Ventilation Process

• Physiology of Respiration

• Cardiopulmonary Pathophysiology

• Respiration
    - Adequate and Inadequate Breathing
    - Patient Assessment
    - Patient Care

• Positive Pressure Ventilation
    - Overview
    - Techniques of Artificial Ventilation

• Oxygen Therapy
    - Importance and Equipment
    - Hazards of Oxygen Therapy
    - Administering Oxygen
    - Supplemental Oxygen for Patients with Chest Pain

• Special Considerations

• Assisting with Advanced Airway Devices

• Chapter Review

• Important Reminders

• Questions to Consider

• Critical Thinking

Physiology and Pathophysiology

Mechanics of Breathing

• Ventilation: The process of moving air into (inhalation) and out of (exhalation) the chest.
    - Inhalation is an active process:
      - Chest muscles expand.
      - Diaphragm contracts.
      - Size of the chest increases.
      - Negative pressure pulls air into the lungs.
    - Exhalation is a passive process:
      - Chest muscles and the diaphragm relax.
      - Size of the chest decreases.
      - Positive pressure pushes air out of the lungs.

• Tidal Volume: The amount of air moved in one breath.

• Minute Volume: The amount of air moved into and out of the lungs per minute.

• Gas Exchange: Ventilation is designed to move air to and from the alveoli for gas exchange.
    - Dead Space: Not all air breathed reaches the alveoli; some air occupies dead space.
    - Alveolar Ventilation: Refers to the amount of air that actually reaches the alveoli; affected by tidal volume, and changes in rate or volume.

Physiology of Respiration

• Alveoli: Ends of the bronchioles, consisting of inflated sacs ventilated during the air exchange process.
    - Pulmonary Capillaries: Bring blood close to alveoli.
    - The thin walls of alveoli and capillaries facilitate gas exchange:
      - Oxygen from alveoli moves into the blood.
      - Carbon dioxide from blood moves into alveoli.

• Diffusion: Movement of gases from high concentration to low concentration.
    - Pulmonary Respiration: Involves diffusion of oxygen and carbon dioxide between alveoli and blood.
    - Cellular Respiration: Involves diffusion of oxygen and carbon dioxide between cells and blood.

• Both pulmonary and cellular respiration depend on the cooperation of the respiratory and circulatory systems, often referred to as the cardiopulmonary system or ventilation-perfusion (V/Q) match.

Cardiopulmonary Pathophysiology

• Mechanical failures limiting pressure changes in the chest can include:
    - Stab Wounds: Allowing air into the cavity.
    - Loss of Nervous Control: Prevents innervation of respiratory muscles.
    - Painful Chest Wall Injuries: Limit chest movement.
    - Bronchoconstriction: Limits airflow.

• Issues with gas exchange can impair oxygen and carbon dioxide diffusion:
    - Low Oxygen Levels: Inhalation difficulties due to environmental conditions.
    - Alveolar Dysfunction: Compromises gas exchange.

• Circulation issues can prevent adequate oxygen delivery to body cells:
    - Significant Blood Loss: Reduces blood circulation to alveoli.
    - Insufficient Hemoglobin: Affects oxygen transport.

Respiration

Adequate and Inadequate Breathing

• Adequate Breathing: Necessary for maintaining oxygen supply to brain and body cells.
    - Hypoxia: Low oxygen levels.
    - Hypercapnia: High levels of carbon dioxide.
    - Assessment involves evaluating oxygenation and carbon dioxide removal through the cardiopulmonary system.

• Compensation Mechanisms: When the system fails, the body compensates through increased respiratory rate and heart rate, and blood vessel constriction.
    - Respiratory Distress: Compensation working, with normal mental status, skin color, and normal oxygenation.
    - Respiratory Failure: Compensation not effective; metabolic needs unmet, precedes respiratory arrest.

• Inadequate Breathing:
    - Occurs when compensatory mechanisms fail; assessment requires attention to respiratory rate, depth, and quality.

Patient Assessment

• Determine if Patient is Breathing

• Assess adequacy by checking:
    - Signs of Adequate Breathing:
      - Equal chest expansion during inhalation.
      - Audible air movement.
      - Typical skin color.
      - Normal respiratory rate, rhythm, quality, depth.
    - Signs of Inadequate Breathing:
      - Altered mental status.
      - Absent or minimal chest movement.
      - Changed pulse rate (e.g., slow in children).
      - No air movement at nose or mouth.
      - Diminished or absent breath sounds.
      - Abnormal lung sounds (e.g., wheezing, stridor).
      - Cyanosis indicators (skin, lips, etc.).
      - Patient inability to speak or labored breathing trend.

Patient Care

• Intervention for Non-breathing Patients: Provide artificial ventilation and supplemental oxygen for those with inadequate breathing.

• Act promptly with recognition of inadequate breathing:
    - Intervene when efforts fail to meet physiological demands.
    - Prioritize aggressive intervention over hesitation to act.

Positive Pressure Ventilation

Overview

• Artificial Ventilation: Use positive pressure to deliver air/oxygen into the lungs.
    - Specifically used when patient stops breathing or has inadequate breathing.
    - Works opposite the body’s natural inhalation mechanism.

• Negative Side Effects of Positive Pressure:
    - Drops in cardiac output and blood pressure due to difficulty refilling heart chambers.
    - Risk of gastric distention as air may enter the stomach.
    - Potential for hyperventilation leading to oxygen imbalance in the body.

Techniques of Artificial Ventilation

• Common Methods:
    - Mouth-to-mask
    - Two-rescuer bag-valve mask
    - One-rescuer bag-valve mask

• Precautions:
    - Avoid failure to ventilate in patients with vomiting or airway obstruction.
    - Ensure protective strategies against bodily fluids.

• Ventilation Technique Guidelines:
    - Monitor chest movement.
    - Adjust ventilation rates according to the patient’s needs.
    - Modify approach based on breathing speed (rapid vs. slow).

• Airway Management:
    - Positioning: Optimal head-elevated, sniffing position is essential for airway clearance.
    - Sealing the Mask: Proper mask placement around the nose and chin ensures air delivery.

Oxygen Therapy

Importance of Supplemental Oxygen

• Oxygen therapy benefits and necessities:
    - Recognized as an essential therapeutic agent; however, it's a drug that must be administered carefully.
    - Risks include patient harm if too little or too much is given; especially important for patients with cardiac concerns.

Oxygen Therapy Equipment

• Required equipment characteristics:
    - Must be safe, portable, and effective; includes:
      - Cylinders: Different sizes identified (D, E, M, G, H) ranging from 350 liters to 6,900 liters.
      - Regulators and Delivery Devices: Should align with safe operation protocols.

• Safety Considerations:
    - Maintain cylinder safety protocols (correct handling, storage, and operational precautions to avoid hazards).
    - Regular testing and compliance with safety standards are mandatory.

Hazards of Oxygen Therapy

• Nonmedical Hazards: Rare yet dangerous.
    - Potential for tanks becoming projectiles if damaged.
    - Risks of fire escalation due to oxygen presence.

• Medical Hazards: Can develop with prolonged exposure or incorrect dosing leading to:
    - Oxygen toxicity.
    - Respiratory complications in patients with COPD or existing heart issues.

Administering Oxygen

• Various Devices Available:

• Utilize appropriate techniques as per instructor guidance for specific equipment used within the clinical setting.

Supplemental Oxygen for Patients with Chest Pain

• Administer Oxygen especially if experiencing:
    - Shortness of breath, hypoxia, low blood saturation levels.

• Use of masks (e.g., nonrebreather masks) with different flow rates (15 liters per minute for high concentration oxygen).

• Implementation of the appropriate device is critical based on patient status.

Special Considerations

• Facial Injuries: May require suctioning and airway adjuncts for airway management.

• Obstructions: Employ alternate methods (e.g., abdominal thrusts) when suctioning is inadequate.

• Dental Appliances: Caution advised; retain dentures unless they obstruct the airway.

• Pediatric Considerations:
    - Unique anatomical characteristics warrant special handling and techniques for airway maintenance.
    - Oxygen consumption rate is higher; thus, specific pediatric equipment must be utilized.

Assisting with Advanced Airway Devices

Preparing the Patient for Intubation

• Prepare patients through supplemental oxygen and positioning.

• Understand the BURP maneuver: directing throat manipulation to assist intubation.

Ventilating the Intubated Patient

• Maintain stable tube placement during ventilation; monitor changes in resistance and patient status.

Assisting with Trauma Intubation

• Ensuring in-line stabilization is vital during the intubation process in trauma scenarios.

Chapter Review

• Recognizing respiratory failure indicators and appropriate interventions is crucial for patient care.

• Emphasis on oxygen application for both breathing and non-breathing patients in various conditions.

Important Reminders

• Always utilize personal protective equipment when managing airway situations.

• Continual assessment of the patient's respiratory condition is necessary as changes can occur rapidly.

• Proper techniques in ventilation demonstrate notable differences compared to natural breathing and may have side effects.

Questions to Consider

• Symptoms reflecting respiratory distress and protocols for identification.

• Techniques variations for ventilation as per traumatic or non-traumatic scenarios.

Critical Thinking

• Case evaluations and symptom recognition to differentiate respiratory failure signs warranting intervention.

• Application of oxygen delivery systems and understanding individual patient needs remain fundamental.