Vaso-Occlusive Crisis

Read Complete Research Material


Vaso-occlusive Crisis

Vaso-occlusive Crisis

The main purpose of this paper is to discuss a case study of a patient suffering from the vaso-occlusive crisis. The case presented here is of a patient named Derrick, who has been suffering from this disease and got hospitalized 3 times in 6 months. Because of this disease he felt so depressed. This paper discusses the ways that how manage with clients suffering from the vaso-occlusive crisis and what should be the best treatment methods for them in order to reduce the stigma and depression of the patient. This paper also discusses that what is the importance of health care provider's knowledge in the management of sickle cell disease?

Sickle cell anaemia, haemoglobin S or sickle haemoglobin is named for the characteristic shape of sickle (sickle in English) that adopts the erythrocytes with decreasing oxygenation.

The most frequent clinical features are vaso-occlusive crisis (VOC) that precipitate in acute episodes of pain and lead ultimately to organ failure and death.

The heterozygous state for sickle cell disease appears to confer some protection against malaria, that is why the gene may have persisted over time. The diagnosis of sickle cell anaemia in homozygous or heterozygous state is based on the identification of Hb by electrophoretic techniques, chromatography or mass spectrometry. Although other simpler techniques allow us to suspect its existence as the induction of sickling and the study of solubility is in a phosphate buffer.

As a result of the mutation, when haemoglobin is deoxygenated it undergoes spontaneous polymerization to form a crystalline gel. Each polymer consists of 14 longitudinal beams deoxy-Hb that are arranged as a body tactoids, insoluble and rigid cylindrical structure. Because of these polymers, it breaks the red cell cytoskeleton by adopting the characteristic shape of sickle cell.

Although the phenomenon of sickling is reversible, between 5 and 50% of sickle erythrocytes that fails to recover its original shape, being eliminated by the mononuclear phagocytic system. On the other hand, erythrocytes have altered a great decrease in cell volume and a large increase in haemoglobin concentration. This is because the deoxy-Hb induces alterations of the erythrocyte membrane (change in the composition and distribution of phospholipids in the bilayer) that are translated by a profound dehydration. In addition, sickle cells exhibit a greater tendency to adhere to vascular endothelium by promoting the formation of micro thrombi and peripheral vascular occlusions.

Interestingly, haemoglobin S may interact with other forms of haemoglobin in particular with fatal haemoglobin (HbF). In the presence of this form of haemoglobin it reduces the degree of polymerization of HbS, which explains why sickle cell anemia are never presented during the neonatal period or hereditary persistence of fatal haemoglobin.

The main characteristic of haemoglobin S is its ability to polymerize under certain conditions, especially in case of hypoxia. Haemoglobin S polymer has a reduced affinity for oxygen. The succession in time cycles of polymerization-depolymerisation leads to modification of the physical characteristics of red blood cells, giving it an appearance in ...
Related Ads