Q&A: Vasodilator therapy to preserve renal function

Q: I’ve been told that vasodilator therapy can be used to preserve renal function, but I’m having trouble understanding how. Could you explain it to me?

A: You’ve likely heard people refer to vasodilator therapy in the context of cardiorenal syndrome—an umbrella term used to define disorders of the heart and kidneys where an acute or chronic dysfunction in one organ may lead to an acute or chronic dysfunction in the other. It’s a tricky condition to treat due to the fact that treatment of the heart failure can also cause decline in the function of the kidneys and vice versa.

Vasodilators are medications that open up or dilate blood vessels by relaxing the muscles in the walls of arteries and veins by preventing them from tightening causing narrowing of vasoconstriction. They are used in treating both acute and chronic heart failure by increasing cardiac output by lowering the peripheral vascular resistance that occurs in heart failure by opening up the blood vessels (vasodilation) and allowing the blood to flow more easily decreasing the systemic vascular resistance. If the blood vessels constrict (vasoconstriction) it will lead to an increase in systemic peripheral resistance. If referring to resistance within the pulmonary vasculature, it is referred to as pulmonary vascular resistance.

When the heart no longer pumps blood efficiently, it becomes congested with blood causing pressure to build up in the main vein connected to the kidneys which in turn will also lead to congestion in the kidneys. Because of this, the kidneys may not be getting enough oxygenated blood. When the kidneys become impaired, the hormone system goes into overdrive trying to increase the amount of blood to the kidneys, which ultimately causes the heart to have to work harder.

I suggest having a conversation with the physicians in either your nephrology or cardiology department to better explain this condition and the common clinical indicators necessary for validation within your facility. Also be sure to touch base with your CDI and coding colleagues for additional insight and common conundrums they’ve faced to help provide context for your own record review activities.

Editor’s Note: Sharme Brodie, RN, CCDS, CCDS-O, CDI education specialist and CDI Boot Camp instructor for HCPro in Middleton, Massachusetts, answered this question. For information, contact her at sbrodie@hcpro.com. For information regarding CDI Boot Camps, click here. This article originally ran in June 2019 and has been updated according to all new coding and documentation guidelines.