User:Anesthesiastudent2024/Cardiogenic shock

I will be editing the "Treatment" section which I have copied and pasted from the Cardiogenic shock article below. Here are the following things I would like to change about this section:

- I believe the last sentence about intravenous dobutamine is redundant and also does not fit the general flow of the paragraph, so I will delete it.

- I will clean up the first few sentences on pharmacotherapy

- I will augment the section on mechanical support devices by breaking it up into sub-titles within the "Treatment" section, and will give a more in-depth explanation of each one (intraaortic balloon pump, left ventricular assist device, and ECMO).

Lead
Cardiogenic shock (CS) is a medical emergency resulting from inadequate blood flow to the body's organs due to the dysfunction of the heart. Signs of inadequate blood flow include low urine production (<30 mL/hour), cool arms and legs, and decreased level of consciousness. People may also have a severely low blood pressure and heart rate.

Causes of CS include cardiomyopathic, arrhythmic, and mechanical. CS is most commonly precipitated by a heart attack.

Treatment of CS depends on the cause with the initial goals to improve blood flow to the body. If cardiogenic shock is due to a heart attack, attempts to open the heart's arteries may help. Certain medications, such as dobutamine and milrinone, improve the heart's ability to contract and can also be used. When these measures fail, more advanced options such as mechanical support devices or heart transplantation can be pursued.

CS is a condition that is difficult to fully reverse even with an early diagnosis. With that being said, early initiation of treatment may improve outcomes. Care should also be directed to any other organs that are affected by this lack of blood flow (e.g., dialysis for the kidneys, mechanical ventilation for lungs dysfunction).

Mortality rates for CS are high but have been decreasing in the United States. This is likely due to its rapid identification and treatment in recent decades. Some studies have suggested that this is possibly related to new treatment advances. Nonetheless, the mortality rates remain high and multi-organ failure in addition to CS is associated with higher rates of mortality.

Treatment
Medication Therapy

Initial management of cardiogenic shock involves medications to augment the heart's function. Certain medications, such as dobutamine or milrinone, enhance the heart's pumping function and are often used first-line to improve the low blood pressure and delivery of blood to the rest of the body.

Patients who have cardiogenic shock unresponsive to medication therapy may be candidates for more advanced options such as a mechanical circulatory support (MCS) device. There are several types of MCS devices, the most common being intra-aortic balloon pump (IABP), left ventricular assist device (LVAD) and venous-arterial extra-corporeal membrane oxygenation (VA-ECMO). It is important to note, however, that none of these devices are not permanent solutions but rather are a bridge to a more definitive therapy such as a heart transplantion.

Intra-aortic balloon pump

An intra-aortic balloon pump (IABP) is a device placed by a cardiac surgeon into the descending aorta. It consists of a small balloon filled with helium that helps the heart to pump blood by inflating during diastole (the resting phase of the cardiac cycle) and deflating during systole (the contracting phase of the cardiac cycle). IABPs do not directly increase cardiac output, but importantly, they decrease the amount of pressure that the heart has to pump against, thereby allowing for more blood flow and oxygen to be delivered to the heart muscles.

The IABP has been around for several decades and is most commonly used first-line of the MCS devices. However, it is not without its potential complications. Potential complications include injury upon insertion of the device to arteries supplying the spinal cord as well as risks with any procedure such as bleeding and infection. Contraindications to an IABP include aortic dissection, an abdominal aortic aneurysm, and irregularly fast heart beats.

Left ventricular assist device

There are several types of left ventricular assist devices (LVAD), with the Impella devices being some of the most common. This device is placed by a cardiac surgeon into the left ventricle of the heart and essentially acts as a pump, drawing blood from the left ventricle and pushing it out into the aorta so that it could be delivered to the rest of the body. Unlike the IABP, the Impella acts independently from the cardiac cycle. It can be adjusted to pump at faster rates to take blood out of the left ventricle and into the aorta more quickly, thereby decreasing the amount of work that the left ventricle has to do. While the Impella is commonly used in settings of cardiogenic shock, some evidence suggests that it placing an Impella device in an acute cardiogenic shock setting, where the heart fails to pump suddenly, may not necessarily guarantee increased survival.

Potential complications specific to an Impella device include hemolysis (shearing of the blood cells) as well as the formation of lesions on the heart valve, namely the mitral or aortic valves. Contraindications to an Impella device insertion include aortic dissection, the presence of a mechanical aortic valve, and the presence of a blood clot in the left ventricle.

Venous-arterial extra-corporeal membrane oxygenation

Venous-arterial extra-corporeal membrane oxygenation (VA-ECMO) is a circuit support system that is meant to replace the function of the heart as it heals or awaits a more definitive treatment. It consists of a circuit that essentially drains blood from a patient's venous system, runs that blood through a circulator which adds oxygen and removes carbon dioxide, and ultimately returns blood back into the patient's arterial system where the newly oxygenated blood can be delivered to the person's organs. Some evidence suggests that the combination of both an Impella device and VA-ECMO may decrease the heart's pulmonary capillary wedge pressure, thereby decreasing the amount of stress on the cardiac muscles.

Because VA-ECMO is a very invasive procedure, it is not usually the first-line chosen device for patients in cardiogenic shock and is often reserved only for patients who have not only cardiogenic shock but also respiratory failure and/or concomitant cardiac arrest.

Potential complications specific to VA-ECMO include an air embolism, pulmonary edema, and blood clotting in the circuit machine.