sickling
Process by which red blood cells containing hemoglobin S deform into rigid, crescent shapes under deoxygenated conditions.
Full Definition
Sickling is the pathophysiologic process whereby erythrocytes containing hemoglobin S undergo shape transformation from flexible biconcave discs to rigid, elongated crescents. This occurs when HbS polymerizes under conditions of decreased oxygen tension, acidosis, or dehydration. The sickled cells become inflexible and prone to hemolysis, while also causing vascular occlusion due to their altered rheologic properties. The sickling process is initially reversible with reoxygenation but becomes irreversible with repeated cycles, leading to membrane damage and shortened red cell lifespan.
Usage
Usage note: Use as a gerund (sickling) or present participle. Avoid redundant phrases like 'sickling process'.
In Context
- "Hypoxia during the flight triggered extensive sickling in the patient's red blood cells." — Emergency department note
- "The peripheral blood smear showed evidence of sickling with numerous irreversibly sickled cells." — Hematology consultation