Patient Case Study: Cardiovascular Emergencies

Patient Case Study

• Dan and Joyce were treating a patient after a car accident
• Initially, the patient was conscious and speaking
• Blood pressure was normal, but the heart rate was rapid
• During transport, the patient became disoriented

Chapter 27: Bleeding and Shock

• Overview of the Cardiovascular System is needed
• Shock assessment and emergency care are required
• External bleeding requires body substance isolation precautions, assessing blood loss, recognizing types of bleeding, and emergency care for external bleeding from the ears, nose, and mouth
• Internal bleeding requires assessing blood loss, recognizing symptoms, and providing emergency care

The Circulatory System

• The heart pumps blood to body organs through the cardiovascular system
• This process is vital; interruption for more than a few minutes can cause death

Heart

• Structure and function: Atrium (right and left) and Ventricle (right and Left)
  • Right atrium receives blood from veins, pumps oxygen-poor blood to the right ventricle
  • Left atrium receives blood from the pulmonary veins (lungs), pumps oxygen-rich blood to the left ventricle
  • Right ventricle pumps oxygen-poor blood to the lungs
  • Left ventricle pumps oxygen-rich blood to the body
• Valves prevent backflow of blood
• Cardiac conductive system: specialized contractile and conductive tissue in the heart; coordinated contraction through electrical impulses
• Automaticity: the ability of cardiac muscle cells to generate their own impulses

Blood Vessels

• Arteries
• Arterioles
• Capillaries
• Venules
• Veins

Arteries

• Carry blood away from the heart
• Major arteries: Coronary (heart), Aorta (major artery leading from the heart), Pulmonary (lungs), Carotid (neck), Femoral (thigh), Radial (lower arm), Brachial (upper arm), Posterior tibial (lower leg), Dorsalis pedis (foot).

Arterioles

• Smallest branches of arteries leading to capillaries

Capillaries

• Tiny blood vessels connecting arterioles and venules
• Found throughout the body
• Allow for nutrient and waste exchange at the cellular level

Venules

• Smallest branches of veins leading to capillaries

Veins

• Carry blood back to the heart
• Major veins: Pulmonary (lungs to left atrium), Venae cavae (superior and inferior - oxygen-poor blood to right atrium)

Blood

• Red blood cells: Give blood its color, carry oxygen to organs, carry carbon dioxide away from organs
• White blood cells: Part of the body's defense against infections
• Plasma: Fluid carrying blood cells and nutrients
• Platelets: Essential for blood clot formation

Pulse

• Left ventricle contraction creates a wave of blood through arteries
• Pulse can be palpated where an artery is near skin surface and over a bone
• Peripheral pulse locations: Radial, Brachial, Posterior tibial, Dorsalis pedis, Carotid, Femoral

Blood Pressure

• Measures pressure in arteries during heart contraction and relaxation
• Systolic: Pressure during ventricle contraction
• Diastolic: Pressure during ventricle relaxation

Perfusion

• Delivers oxygenated blood to organs, removing waste products and carbon dioxide
• Cellular respiration is involved
• Shock (hypoperfusion) is widespread inadequate tissue perfusion.

Shock

• Signs and symptoms: Pale or cyanotic skin, cool or cold skin, rapid weak pulse, altered mental status, rapid breathing, nausea and vomiting, low/decreasing blood pressure (latter is a late sign)
• Shock (hypoperfusion) results in inadequate perfusion of cells with oxygen, nutrients, and removal of metabolic waste products
• Cell and organ malfunction results without prompt recognition and treatment
• Types of shock: Cardiogenic, distributive (septic, anaphylactic, neurogenic), hypovolemic, hemorrhagic

Types of Shock

• Caused by disorders of the pump (cardiogenic), pipe (septic, anaphylactic, neurogenic), or fluid (hypovolemic, hemorrhagic)

Trauma Patients and Shock

• Trauma patients develop shock from blood loss
• This is called hypovolemic shock

Shock (Hypoperfusion) - Signs and symptoms

• Restlessness
• Anxiety
• Altered mental status

Shock (Hypoperfusion) - Signs and symptoms

• Peripheral perfusion
• Delayed capillary refill greater than 2 seconds
• Weak or absent peripheral pulses
• Pale, cool, clammy skin

Shock (Hypoperfusion) - Signs and symptoms - Vital Signs

• Decreased blood pressure (late sign)
• Increased pulse rate (early sign), weak and thready
• Increased breathing rate, shallow, labored, irregular

Shock - Other signs and symptoms

• Dilated pupils
• Marked thirst
• Nausea and vomiting
• Pallor with cyanosis to the lips
• Infants and children can maintain blood pressure until blood volume is less than half gone
• By then, they are close to death
• Less reserve than adults

Emergency Care for Shock

• Body substance isolation
• Maintain airway / artificial ventilation
• Administer oxygen if needed
• Control any external bleeding
• Place patient in shock position (head turned to one side unless suspected of neck injury)
• Keep patient warm and comfortable
• Emergency care for shock can include using a pneumatic antishock garment (PASG)

Emergency Care for External Bleeding

• Bleeding control: concentrated direct pressure (fingertip pressure on bleeding point), diffuse direct pressure, extremity elevation, pressure points, splints

Pressure Splints

• Reduction of bone motion reduces tissue damage, bleeding, and fracture
• The use of air pressure splints can control severe bleeding in soft tissue or fracture injuries
• Pneumatic counterpressure devices(PASG) can be used

Tourniquet

• Used as a last resort to control bleeding, particularly from amputated extremities
• Use wide bandage and secure tightly
• Tourniquets may cause permanent damage

Bleeding from the Ears, Nose, and Mouth

• Potential causes: Injured skull, facial trauma, digital trauma, sinusitis; hypertension, coagulation disorders
• Bleeding from the ears or nose may be a result of skull fracture; do not attempt to stop the bleeding if the result of trauma
• Collect blood with a loose dressing (infection prevention)

Emergency Medical Care for Nose Bleeds

• Position patient sitting, leaning forward
• Apply direct pressure to the fleshy part of nose
• Keep the patient calm.

Internal Bleeding

• Internal bleeding results in significant blood loss, shock, subsequent death
• Suspicion and severity are based on the mechanism of injury and clinical signs/symptoms
• Relationship to mechanism of injury: Blunt trauma(falls, motorcycle, pedestrian, automobile collisions, blast injuries)
• Look for evidence of contusions, abrasions, deformity, impact marks, and swelling
• Penetrating trauma
• Injured/damaged organs lead to concealed bleeding
• Painful, swollen, deformed extremities can also lead to internal blood loss
• Amount of blood loss associated with various injuries (measured in milliliters; e.g., femur 600 mL)

Internal Bleeding (Signs and Symptoms)

• Pain, tenderness, swelling, or discoloration of suspected site of injury
• Bleeding from mouth, rectum, or vagina; other orifices
• Vomiting bright red blood or coffee-ground colored blood
• Dark, tarry or bright red stools
• Tender, rigid, or distended abdomen
• Late signs and symptoms of hypovolemic shock

Emergency Care for Internal Bleeding

• Body substance isolation
• Maintain airway / artificial ventilation
• Administer oxygen if not already done during initial assessment
• Control bleeding in an extremity by direct pressure and splint application
• Immediate transport is critical for patient with signs/symptoms of shock