Shock is a state in which the circulatory system does not deliver enough blood to meet the oxygen and nutrient needs of the tissues. Shock may be the result of the heart not pumping effectively, insufficient blood volume, or massive dilation of vessels causing maldistribution of blood flow.
Significance
When oxygen and nutrients are not delivered to tissue the end result can be a life-threatening situation. In cardiogenic shock, the heart is unable to pump enough blood. The left ventricle of the heart is unable to contract adequately to pump the blood. Not all of the blood is ejected with each heart beat, meaning the ventricle cannot fill completely with the next heartbeat. This causes blood to back up into the lungs, the right side of the heart and eventually into other arteries and veins. Pump failure leads to a decrease in blood pressure and decrease of blood flow to tissues.
Causes
According to "Nursing Standard," the causes of cardiogenic shock are limited, and most often occurs following a heart attack. Other heart conditions such as infection in the lining of the heart or inflammation of the heart muscle can cause cardiogenic shock. In rare cases some medications have been known to cause cardiogenic shock.
Symptoms
In cardiogenic shock, a patients condition can deteriorate very quickly. Patients will have decreased urine output, fluid in the lungs, and changes in their level of consciousness. Skin becomes cool and pale, and blood pressure drops.
Dopamine
The goal of treatment for cardiogenic shock is to improve the ability of the heart to pump blood. Giving the patient oxygen is a first-line treatment. Medications called diuretics may be used to help increase urine output and rid excess fluids. Dopamine is a medication used to help increase cardiac output, blood pressure and urine flow in the treatment of shock. According to "Nursing Standard," the use of dopamine has been associated with increased mortality. Other medications that have the same effect may be options to consider.
Outcome
Patients with cardiogenic shock are critically ill and require hospitalization. These patients need close monitoring in an intensive care unit. If the cause of shock is a heart attack, the patient may need invasive procedures to open the blocked artery. In some cases patients may require a ventricular assist device, a mechanical pump, that helps circulate blood to assist the failing heart.
References
- "Essentials of Critical Care Nursing"; McGraw Hill; 2006
- "Nursing Standard"; Understanding hypovolemic, cardiogenic, and septic shock; Garretson; August 2007
- "Dimensions of Critical Care"; Cardiogenic Shock; Holcomb; 2002
