breathing

FATIMA COLLEGE OF HEALTH SCIENCES

EHS201: Introduction to Trauma

Lesson Objectives
  • By the end of this lesson, students will be able to:
    • Explain the principles of ventilation and gas exchange with the pathophysiology of chest trauma.
    • Differentiate between ventilation and respiration.
    • Describe conditions that can interfere with ventilation and respiration.
    • Explain the management of conditions compromising ventilation and oxygenation.
Dispatch
  • Location: Zayed Sports Complex
  • Incident: 15 y/o male struck in the chest by a cricket ball.
Scene Size-Up
  • General Impression:
    • Patient is in a tripod position, holding the right side of the chest.
    • Actively crying.
Primary Survey
  • Findings:
    • No external hemorrhage identified.
    • Airway is patent; patient is able to speak in sentences.
    • Breathing is tachypneic and shallow; contusion noted on right lateral chest over ribs 4-6; no crepitus present.
    • Vital signs show tachycardia; skin is cool and dry; capillary refill less than 2 seconds.
    • Patient's eyes are open spontaneously; oriented; able to lift and hold right arm.
    • Only visible injury is the contusion to the right side of the chest.

Thoracic Anatomy

  • Components:
    • Intercostal artery, vein, and nerve
    • Intercostal space
    • Descending aorta
    • Esophagus
    • Trachea
    • Lungs
    • Heart
    • Pleura
    • Diaphragm lining
    • Aorta
Respiratory Physiology

  • Oxygen Transport:

    • Oxygen is transported across the alveolar–capillary membrane, attaching to hemoglobin in red blood cells for further transport.
    • In parallel, carbon dioxide (CO2) moves from blood plasma into alveoli.

  • Mechanical Ventilation:

    • The mechanical act of moving air into the lungs and alveoli is controlled by the respiratory center of the brain.
    • Chemoreceptors located in the aorta and carotid arteries stimulate the respiratory center.
    • The rate and depth of ventilation are continuously adjusted to maintain normal arterial carbon dioxide (PaCO2) levels.
Breathing Assessment
  • General Observations:
    • Normal breathing is often unnoticeable.
    • If patient’s breathing draws attention, this indicates a potential issue.
    • Examples of problematic breathing include:
    • Breathing audible from across the room.
    • Inability to speak in complete sentences.
    • Patient positioning to ease breathing (e.g., tripoding).
Assessment Methods

  • Look (Observe):

    • Increased respiratory effort, such as:
    • Positioning adjustments.
    • Use of accessory muscles.
    • Retractions and nasal flaring (especially in children).
    • Visible Trauma:
    • Contusions, hematomas, lacerations.
    • Sucking chest wound, puncture wounds.
    • Paradoxical movement of the chest wall.

  • Listen (Auscultate):

    • Auscultation of breath sounds to check for:
    • Presence and equality (right vs left sides).
    • Asymmetry:
      • Decreased or absent breath sounds on one side.
    • Abnormal sounds like wheezing, rales, rhonchi, or crepitus (bony or subcutaneous emphysema).

  • Feel (Palpate):

    • Check for:
    • Bony crepitus, subcutaneous emphysema.
    • Abnormal movement of the chest wall.
    • Bony tenderness on palpation.

Thoracic Injuries

Types of Chest Injuries
  • Pneumothorax:
    • Types:
    • Simple
    • Tension
    • Open
    • Hemopneumothorax
  • Hemothorax
  • Rib Fractures:
    • Types:
    • Simple
    • Flail chest
Pneumothorax

  • Prevalence:

    • Present in up to 20% of severe chest injuries.
    • A simple pneumothorax can progress to a tension pneumothorax if air continues to accumulate.
    • Tension pneumothorax is potentially life-threatening.
    • Needle decompression may be required in severe cases.

  • Descriptions:

    • Simple Pneumothorax:
    • Results from blunt or penetrating injuries.
    • Characterized by decreased or absent breath sounds and mild to moderate ventilatory distress; may progress to tension.
    • Tension Pneumothorax:
    • Occurs from blunt or penetrating injury.
    • Symptoms include decreased or absent breath sounds, marked ventilatory distress, altered mental status, hemodynamic compromise (e.g., tachycardia, jugular venous distention (JVD), tachypnea, hypotension, tracheal deviation).
    • Tracheal deviation is considered an extreme late sign.
Open Pneumothorax
  • Mechanism:
    • Result of penetrating injuries leading to a “sucking” or “bubbling” chest injury.
    • Respiratory distress can range from mild to severe.
    • May involve a hemothorax.
    • The optimal field management method has not been established; however, it involves covering the wound with an occlusive dressing that has a valve.
Hemothorax
  • Mechanism of Injury:
    • Caused by blunt or penetrating injury resulting in bleeding into the pleural cavity.
    • It can be associated with pneumothorax.
    • The presence of air or blood in the pleural space compromises lung capacity.
Rib Fractures
  • Commonality:
    • Most common thoracic injury.
    • Typically involves ribs 4 through 8, laterally.
    • Most prevalent cause of hemothorax.
    • Common complaints include chest pain and shortness of breath.
    • Patients often take short, shallow breaths due to pain.
    • May accompany injuries to internal organs like the liver and spleen.
Flail Chest
  • Definition:
    • Characterized by two or more adjacent ribs fractured in more than one place on the same side of the chest.
    • This leads to a compromise in the structural integrity of the chest.
    • Results in paradoxical movement during breathing.
    • Typically associated with underlying injuries such as pneumothorax, hemothorax, or pulmonary contusion.

Management of Thoracic Injuries

  • Goals:
    • Maintain or restore adequate oxygenation and ventilation by:
    • Administering supplemental oxygen.
    • Assisting with ventilations as necessary.
    • Sealing open chest wounds.
    • Recognizing and decompressing tension pneumothorax.
    • Applying splinting with a cushion to support rib fractures.
    • For flail chest injuries, applying splinting to keep the chest wall symmetrical.
    • Continuous reassessment of breathing is fundamental.
Supplemental Oxygen
  • Administration:
    • Can be delivered via non-rebreathing mask, bag-valve-mask device, or oxygen-powered ventilator.
    • Oxygen should never be withheld from patients in respiratory distress.
    • Oxygen saturation is monitored, with a target SpO2 greater than 94%.
    • Increased levels of inspired oxygen aid in maintaining aerobic metabolism.
Ventilation Support
  • Indications for Support:
    • If respiratory rate is greater than 30 or less than 10 breaths per minute.
    • Signs of insufficient spontaneous tidal volume include:
    • Poor chest rise.
    • Use of accessory muscles.
    • Decreased SpO2 and increased end-tidal carbon dioxide (ETCO2).
    • Consideration for airway management may arise.
Ventilation Devices

  • Types of Ventilation Devices:

    • Bag-Mask Devices
    • Automatic Devices
    • Manually-Triggered Devices

  • Ventilation Rates:

    • Adults: 10-20 breaths per minute; 4-6 ml/kg in lung protective strategies (Physiology 8-10 ml/kg).
    • Children: 15-25 breaths per minute; 4-6 ml/kg in lung protective strategies (Physiology 8-10 ml/kg).
    • Infants: 25-50 breaths per minute; 4-6 ml/kg in lung protective strategies (Physiology 8-10 ml/kg).
    • Inadvertent hyperventilation may lead to poor outcomes in patients with traumatic brain injury.
Monitoring Breathing
  • Techniques:
    • Capnometry and capnography can monitor:
    • Spontaneously breathing patients.
    • Bag-mask devices.
    • Endotracheal tubes.
    • Supraglottic airways.
    • Aim to maintain values between 35 to 45 mm Hg.
    • Caution: may produce false readings in hypotensive patients but can track trends over time.
Management of Tension Pneumothorax: Needle Decompression
  • Procedure:
    • Relieves tension pneumothorax; performed at specific anatomical sites:
    • Fifth intercostal space, anterior-axillary line, over the 5th rib.
    • Second intercostal space, midclavicular line, over the 3rd rib.
    • The selected location may vary based on patient age and body habitus.
    • The technique is utilized by paramedics and advanced care paramedics (ACPs).
Summary
  • Key Responsibilities in Trauma Care for Respiratory Difficulty:
    • Maintaining a patent airway.
    • Administering supplemental oxygen.
    • Supporting and monitoring ventilations.
    • Recognizing and decompressing tension pneumothorax.
References
  • National Association of Emergency Medical Technicians (2020). Prehospital Trauma Life Support, Ninth Edition. Jones & Bartlett Learning.