What is a sickle cell crisis (vaso-occlusive crisis)?

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From the Guidelines

A sickle-cell crisis, also known as a vaso-occlusive crisis, is a painful episode that occurs when abnormally shaped red blood cells block small blood vessels, causing tissue damage and severe pain, and is characterized by a chronic haemolytic anaemia, painful vaso-occlusive crises and acute and chronic end-organ damage, as described in the 2021 guideline on the peri-operative management of patients with sickle cell disease 1.

Definition and Characteristics

A sickle-cell crisis happens in people with sickle cell disease, a genetic condition where hemoglobin (the oxygen-carrying protein in red blood cells) is abnormal, causing cells to become rigid and sickle-shaped when oxygen levels are low.

  • The crisis is marked by sudden, intense pain in the chest, abdomen, joints, or bones that can last hours to days.
  • The underlying mechanism involves the sickle-shaped cells getting stuck in small blood vessels, blocking blood flow and causing oxygen deprivation to tissues, which leads to inflammation and pain.

Treatment and Management

Treatment focuses on pain management with medications like acetaminophen, NSAIDs, and sometimes opioids like morphine or hydrocodone, depending on pain severity, as well as hydration and oxygen therapy if necessary 1.

  • Hydration is crucial, with patients needing to drink plenty of fluids or receive IV fluids in severe cases.
  • For severe crises, hospitalization might be required, and blood transfusions are sometimes needed, although the management of hyperhemolysis, a potential complication of transfusions, remains unclear 1.

Triggers and Prevention

Triggers for crises include dehydration, extreme temperatures, high altitude, stress, and infections.

  • Prevention and management of complications from birth, and death in childhood is uncommon in the UK (1–2%) with optimal multidisciplinary care in a specialist haematology clinic 1.

From the Research

Definition of Sickle Cell Crisis (Vaso-occlusive Crisis)

  • A sickle cell crisis, also known as a vaso-occlusive crisis, is a complication of sickle cell disease that occurs when sickled red blood cells obstruct the flow of blood, leading to tissue ischemia and pain 2.
  • It is characterized by severe pain, often accompanied by fever, swelling, and other symptoms 3, 4.

Pathophysiology of Vaso-occlusive Crisis

  • The pathophysiology of vaso-occlusive crises involves the polymerization of abnormal sickle hemoglobin, inflammation, and adhesion 2.
  • This leads to the obstruction of small blood vessels, resulting in tissue damage and pain 2.

Management of Vaso-occlusive Crisis

  • The management of vaso-occlusive crisis typically involves the use of analgesics, such as opioids and non-opioids, to relieve pain 3, 4, 5.
  • Other treatments, such as hydroxyurea, L-glutamine, crizanlizumab, and voxelotor, have been approved for reducing the frequency of vaso-occlusive crises 2.
  • Guidelines for the management of acute and chronic pain in sickle cell disease have been developed by the American Society of Hematology, emphasizing the importance of interdisciplinary care and patient-centered decision making 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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