Index
It occurs when the adequate supply of oxygen and nutrients to the body’s organs and tissues is compromised.
This occurs as a direct result of an obstruction to blood flow in or out of the heart.
If the blood flowing to the heart is obstructed, it causes a decrease in cardiac output due to impaired diastolic filling.
If the blood flowing out of the heart is obstructed, it causes a decrease in cardiac output due to excessive overload.
Causes
The most common causes of obstructive shock in children are:
- Pneumothoraxic tension.
- The pulmonary embolism .
- Cardiac tamponade.
There are also several birth defects that can cause obstructive shock. Examples include:
- Critical aortic stenosis.
- Coarctation of the aorta.
Both the signs and symptoms of obstructive shock and the treatment and treatment of obstructive shock depend on the cause.
Pneumotoraxic tension
Tension pneumothorax is the accumulation of air within the pleural space.
Causes
Causes of tension pneumothorax in children include:
- Trauma.
- Asthma.
- Cystic fibrosis.
- Pneumonia.
- Excessive positive pressure during manual or mechanical ventilation.
Once a tension pneumothorax occurs, air can continue to collect within the pleural space but cannot escape. This continual accumulation of air increases pressure and eventually obstructs the return of venous blood to the heart.
The obstruction results in a decrease in diastolic filling.
Signs and symptoms
The following list provides other signs and symptoms of tension pneumothorax using the primary assessment model (ABCDE).
- Airway: tracheal deviation to the contralateral side.
- Breathing: increased work of breathing, increased respiratory rate, shortness of breath, and decreased lung sounds on the affected side.
- Circulation: neck vein distention, rapid and severe hypotension, tachycardia rapidly degrades into bradycardia and PEA.
- Disability: decreased level of consciousness.
- Exposure: pale and cold extremities.
Management of tension pneumothorax
The definitive treatment for obstructive shock caused by tension pneumothorax is needle decompression and placement of a chest tube in the affected area.
Cardiac tamponade
Cardiac tamponade is the accumulation of fluid or blood within the pericardial sac.
As fluid accumulates, the increase in pressure decreases venous return to the heart and produces right ventricular compression, resulting in a progressive decrease in the end diastolic volume of the right ventricle. The decrease in end diastolic volume compromises cardiac output, leading to symptoms of shock.
Signs and symptoms
The following list provides other signs and symptoms of cardiac tamponade using the primary assessment model (ABCDE).
- Airway: may have compromised airway if level of consciousness decreases.
- Breathing : increased work of breathing and respiratory rate; respiratory distress
- Circulation: tachycardia, decreased peripheral pulses, jugular vein distention, poor capillary recharge, muffled heart sounds, narrow pulse pressure.
- Disability : decreased level of consciousness.
- Exposure: cold extremities.
Management of cardiac tamponade
The primary treatment for cardiac tamponade is pericardiocentesis. If cardiac tamponade is suspected and the patient is not in cardiac arrest, an expert consultation should be performed.
If cardiac arrest is ongoing or imminent and cardiac tamponade is suspected, emergency pericardiocentesis may be performed.
Pulmonary embolism
Pulmonary embolism occurs when the pulmonary artery or its branches are partially or totally occluded. Common causes of pulmonary embolism include blood clots (most common), air, and fat.
Children who have existing risk factors are at increased risk for pulmonary embolism. Some risk factors include indwelling central venous catheters, sickle cell disease, and bleeding disorders.
Signs and symptoms
The following list provides signs and symptoms of pulmonary embolism using the primary assessment model (ABCDE).
- Airway : may have compromised airway if level of consciousness decreases
- Breathing: increased work of breathing and respiratory rate; respiratory distress
- Circulation : tachycardia, cyanosis, chest pain, and hypotension. Venous congestion: right side (hepatomegaly, ascites, abdominal pain, pleural effusion, edema, jugular venous distention)
- Disability : decreased level of consciousness.
- Exposure: cold extremities.
Management of pulmonary embolism
Pulmonary embolism should be confirmed by contrast-enhanced computed tomography, echocardiography, or angiography.
The primary treatment for pulmonary embolism is anticoagulant therapy, but since anticoagulant therapy does not work immediately, fibrinolytic therapy should be considered for severe cases of pulmonary embolism.
Crash Management Fundamentals
As with all forms of shock, management of obstructive shock should focus on the critical components of shock management.
The following should be considered: positioning, airway and breathing, vascular access, fluid resuscitation, monitoring, frequent reassessment, laboratory studies, drug therapy, and expert consultation.
