Adult CCRN Practice Exam

Hyperviscosity syndrome occurs when the blood becomes unusually thick due to excess serum proteins or an increased cellular component, which slows flow in small vessels and leads to tissue hypoperfusion. This thickened blood impairs microcirculation, producing symptoms such as headaches, dizziness, blurred vision, and mucosal bleeding as tissues don’t receive adequate blood flow. Common causes include high levels of immunoglobulins (like IgM in Waldenström macroglobulinemia) or increased red cell mass (as in polycythemia vera) and sometimes other plasma cell disorders. Treatments focus on rapidly reducing viscosity (often with plasmapheresis) and addressing the underlying condition. The other options describe an allergic reaction, an infection, or dehydration from a hormonal imbalance, which don’t explain the increased viscosity and resulting impaired perfusion.