What is cardiorenal syndrome (CRS) in a pediatric patient?

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From the Guidelines

Cardiorenal syndrome is when your heart and kidneys aren't working well together, and it's like a circle where one problem makes the other worse. Imagine your heart as a pump that moves blood around your body, and your kidneys as filters that clean your blood. When your heart gets sick and becomes weak, it can't pump blood well to your kidneys. This means your kidneys don't get enough blood to do their cleaning job properly. At the same time, when your kidneys don't work well, they can't remove extra water and waste from your body. This extra fluid makes your heart work harder, which can make your heart even more tired and weak. There are different types of cardiorenal syndrome, including:

  • Type 1: Acute heart failure causes acute kidney injury (AKI)
  • Type 2: Chronic heart failure causes CKD
  • Type 3: AKI or acute renal failure causes acute cardiac failure
  • Type 4: CKD causes chronic cardiac dysfunction, including heart failure, as described in a narrative review published in the British Journal of Pharmacology 1. Your body needs both your heart and kidneys to be healthy because they help each other. Doctors help fix this by giving medicines that make your heart stronger and help your kidneys remove extra water. They also might tell you to eat less salt because salt makes your body hold onto water, which makes your heart work harder.

From the Research

What is Cardiorenal Syndrome?

  • Cardiorenal syndrome (CRS) is a condition where the heart and kidneys do not work well together 2, 3, 4, 5, 6.
  • It happens when one organ (the heart or the kidneys) is not working properly, and that makes the other organ not work well either 3, 4, 5, 6.

How Does it Happen?

  • When the heart is not working well, it can't pump enough blood to the kidneys, so they don't get the oxygen and nutrients they need 2.
  • This can make the kidneys not work properly, and that can make the heart work even harder, which can make things worse 2, 4.
  • It's like a circle: the heart and kidneys are connected, and when one is not working well, it can affect the other 3, 5, 6.

Types of Cardiorenal Syndrome

  • There are five types of cardiorenal syndrome, depending on which organ is affected first and how long the problem lasts 4, 5.
  • Type 1 is when the heart stops working suddenly, and that makes the kidneys not work well 4.
  • Type 2 is when the heart is not working well for a long time, and that makes the kidneys not work well either 4.
  • Type 3 is when the kidneys stop working suddenly, and that makes the heart not work well 4.
  • Type 4 is when the kidneys are not working well for a long time, and that makes the heart not work well either 4.
  • Type 5 is when both the heart and kidneys are not working well at the same time, because of another disease like diabetes or sepsis 4, 5.

Explanation for a 5-year-old

  • Imagine your heart and kidneys are two friends who need to work together to keep you healthy 2, 3, 4, 5, 6.
  • If one friend is not feeling well, the other friend might not feel well either, and that can make it hard for them to work together 2, 4.
  • But if we can help one friend feel better, the other friend might start to feel better too, and that can make you feel healthier and happier 3, 5, 6.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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