Congestive Heart Failure
Instructional Review (Continued)
Symptoms of CHF
Many symptoms of heart failure result from the congestion that develops as fluid backs up into the lungs and leaks into the tissues. Other symptoms result from inadequate delivery of oxygen-rich blood to the body’s tissues. Since heart failure can progress rapidly it is imperative that patients receive treatment followed by transport if any of the following symptoms are detected.
Left-Sided Heart Failure
Left ventricular failure occurs when the left ventricle fails as an effective forward pump, causing backpressure of blood into the pulmonary circulation, often resulting in pulmonary edema. In left ventricle failure, the left ventricle cannot eject all the blood delivered to it from the right heart. Left atrial pressure rises and subsequently transmitted to the pulmonary veins and capillaries. When pulmonary capillary pressure becomes to high, the fluid portion of the blood is forced into the alveoli, resulting in pulmonary edema. Progressive accumulation in the alveoli decreases the oxygenation capacity of the lungs, and can result in death from hypoxia.
Signs / Symptoms
Severe Respiratory Distress - Severe respiratory distress is defined as orthopnea or dyspnea. If left ventricular failure is the result of chronic overload (as opposed to AMI), the patient is likely to give a history of a week or two of paroxysmal nocturnal dyspnea.
Severe apprehension, Agitation, And Confusion - left ventricular failure and pulmonary edema can result in hypoxia. The patient often has a smothering feeling. The patient often becomes apprehensive and frightened. As hypoxia worsens agitation and confusion worsen. If hypoxemia is severe cardiac arrest may follow quickly.
Cyanosis - Results from inadequate exchange of oxygen and carbon dioxide in the lungs, resulting from pulmonary edema. Thus the Pao2 level falls and the PaCo2 levels increase
Diaphoresis - Often results from sympathetic stimulation, either from apprehension associated with pulmonary edema or from MI.
Aventitious Lung Sounds (pulmonary congestion) - these include:
- Rales - especially at the bases of the lungs, result from fluid in the alveoli. Severe rales can be heard all the way to the apex of the lungs and do not clear with coughing.
- Ronchi - is associated with fluid in the larger airways and often includes severe pulmonary edema. Patient s may also cough up edema fluid in the form of foamy blood tinged sputum.
- Wheezes - This occurs in response to reflex airway spasm. The presence of fluid in the alveoli is misinterpreted by the protective mechanisms in the lungs, resulting in broncoconstriction in attempt to keep additional fluid from entering.
Jugular Vein Distension - This does not result directly from left ventricular failure. However, it may be present when backpressure from the left ventricular failure extends through the right side of the heart to the venous circulation. Exam the patient for JVD with patient seated and the head elevated at a 45-degree angle.
Vital signs - There is usually a significant increase in sympathetic discharge to help the body compensate for the left heart failure. The blood pressure is often elevated. The pulse is rapid to compensate for the low stroke volume. The pulse may be irregular if dysrthmias are present and breathing is labored.
Level Of Consciousness - This may vary, the patient may become extremely anxious or apprehensive. As cerebral perfusion decreases and hypoxia increases, the patient may become agitated, confused, and finally unresponsive.
Chest Pain - The presence of chest pains depends on whether a MI has occurred, or the pain may be caused from the respiratory distress.
Prehospital management of left heart failure is aimed at improving oxygenation and decreasing the workload of the heart, mainly by reducing the volume of venous blood return to the heart (preload), so the left ventricle is less overburden. Obtain pertinent medical history and physical exam while initiating treatment. Do not lie the patient supine at any time.
High flow oxygen
Establish IV access (It is imperative that fluids be limited)
Nitoglycerin for peripheral vasodilatation. This will decrease preload and afterload and can lessen the symptoms of left sided heart failure.
Lasix - this is potent loop diuretic with a relaxant effect on the venous system. Effects are seen within 5 minutes.
Morphine Sulfate - this is administered primarily for its hemodynamic properties. Morphine decreases venous return (preload), reduces myocardial work, and helps reduce anxiety.
CPAP - if the patient is not effectively responding to the above treatments they may benefit from this treatment. CPAP provides a continuous pressure the the lungs which can force the accumulated fluid from their lungs back into the circulatory system.
Dopamine - this increases cardiac output by increasing stoke volume. This has little effect on rate and usually will give a positive increase in blood pressure.