Get a detailed medical history – understand all you can about what defect the patient has and how severe the symptoms are. Get surgical history, daily medications, hemodynamic status, and cardiac and lung function.

Reduce left-to-right shunt – Increases in SVR will worsen left-to-right shunting. Sudden increases or decreases in pulmonary vascular resistance or SVR will also be tolerated poorly. Volatile anesthetics, propofol, etomidate, and barbiturates all decrease SVR – so use cautiously.

Limit stress – or anything that would stimulate sympathetic response. Opioids are often used to reduce/eliminate sympathetic responses to pain, laryngoscopy, etc. Use a slow/cautious induction.

Maintain MAP and SVR – Arterial lines and/or central lines are ideally employed to keep tight controls. These patients will not have optimal cardiac reserve.

Avoid shunt reversal – Airway obstruction, hypoventilation, hypoxia, and pulmonary hypertension create greater pressures on the right side of the heart and can reverse the shunt (making it a cyanotic shunt). This is otherwise called Eisenmenger Syndrome.

Debubble – avoid any bubbles in venous lines. These can lead to a paradoxical embolus.

Cardiac bypass – complex congenital defects sometimes require this. Be aware that this may result in hemodilution!

Endocarditis prophylaxis – for 6 months post-surgical repair of the cardiac defect.

VSDs are the most common acyanotic congenital heart defect (CHD). They account for 25-35% of all CHDs.

A VSD is a defect where blood passes from one atrium of the heart to the other. This is most typically from the left ventricle to the right ventricle due to the higher pressures of the left ventricle. This left to right shunt sends oxygenated blood to the right side of the heart. In essence, the problem is that the body is getting less volume of the oxygenated blood. Shifts in pressure to the right compartments of the heart, and then to the lungs, can also create their own sets of problems.

There are three categories of VSDs. In order of most common to least common they are: Membranous (infracristal), muscular, and infundibular.

Possible signs and symptoms – loud holosystolic murmur in the left lower sternal border, cardiomegaly, increased pulmonary artery pressures, aortic regurgitation, shortness of breath, sweating, fatigue, and poor weight gain.

The majority of these will spontaneously close. If medical therapy does not work, surgical correction may be indicated.