Anemia occurs in patients with chronic kidney disease due to?

NHM UP Staff Nurse - 2019

Medical Surgical Nursing

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Appeared in: NHM UP Staff Nurse - 2019

Explanation

The primary cause of anemia in chronic kidney disease (CKD) is the failure of the diseased kidneys to produce adequate amounts of the hormone erythropoietin (EPO).
Erythropoietin is the principal hormone that signals the bone marrow to initiate erythropoiesis, the process of producing new red blood cells (RBCs).
In CKD, as kidney tissue is progressively damaged, the capacity to secrete EPO diminishes, leading to reduced RBC production.
This results in a specific type of anemia known as normocytic, normochromic anemia, where the red blood cells are of normal size and hemoglobin content, but their total number is low.

Option A: Decreased plasma osmolality refers to a state of fluid excess or hyponatremia (hemodilution). While fluid and electrolyte imbalances are common in CKD, they do not cause the fundamental failure of red blood cell production that characterizes anemia of CKD.
Option B: Increased plasma osmolarity indicates dehydration or an excess of solutes in the blood. This condition is the opposite of the fluid overload often seen in advanced CKD and is not a cause of anemia.
Option D: Renin is an enzyme produced by the kidneys that plays a central role in the Renin-Angiotensin-Aldosterone System (RAAS) to regulate blood pressure and sodium balance. Its dysregulation in CKD is a major cause of hypertension, not anemia.

Clinical Relevance

Nursing practice connection: Knowing Pathophysiology of anemia in chronic kidney disease (CKD) helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Nurses are responsible for administering erythropoiesis-stimulating agents (ESAs), such as epoetin alfa or darbepoetin alfa, which are synthetic forms of EPO used to treat anemia in CKD.
Monitoring hemoglobin levels is crucial. The goal is typically to maintain hemoglobin between 10-11.5 g/dL, as targeting higher levels has been associated with increased cardiovascular risks like stroke and hypertension.
Patient education should include the importance of adequate iron intake (often requiring IV iron supplementation), as iron is a critical component for hemoglobin synthesis and the effectiveness of ESA therapy.

How to Approach the Question

First, identify the core concepts in the question: 'Anemia' and 'Chronic Kidney Disease' (CKD).
Recall the major functions of the kidneys, which include filtration of waste, fluid and electrolyte balance, and endocrine functions (producing hormones).
Focus on the endocrine functions: the kidneys produce erythropoietin (EPO), renin, and activate Vitamin D.
Connect each hormone to its primary function. EPO stimulates red blood cell production. Renin regulates blood pressure. Activated Vitamin D regulates calcium and bone metabolism.
Analyze the clinical problem presented: anemia (a deficiency of red blood cells).
Logically link the problem (anemia) to the failure of the corresponding kidney function (decreased EPO production).

Concept Tested & Keywords

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