Epistaxis, or nosebleeds, occurs when small, swollen blood vessels in the nasal mucous membrane rupture. Typically, the anterior septum is the primary site of occurrence.
Etiology
Possible causes of this condition include high blood pressure, trauma, low humidity, upper respiratory tract infections, allergies, foreign bodies, nasal inhalation of corticosteroids or illicit drugs, excessive use of decongestant nasal sprays, facial or nasal surgery, anatomic malformation, tumors, or systemic...

Pulmonary embolism (PE) occurs when a thrombus, fat or air embolus, amniotic fluid, or tumor tissue blocks one or more pulmonary arteries. These blockages originate in the venous system or the right side of the heart.EtiologyPE primarily arises from deep vein thrombosis (DVT) and other hypercoagulable states, such as inherited thrombophilias. Additional etiological factors include venous stasis, commonly seen in obesity, and endothelial injury from surgery and trauma. Less common causes include...

Hemostasis, the process that stops bleeding after a blood vessel injury, is crucial for maintaining the integrity of the circulatory system. However, disorders of hemostasis can disrupt this delicate balance, leading to either excessive clotting or bleeding. These disorders can be broadly classified into thromboembolic disorders and bleeding disorders.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.

DialyzersA hemodialysis (HD) dialyzer is a plastic cartridge containing thousands of parallel hollow fibers, which serve as semipermeable membranes. These fibers are typically made from cellulose-based or other synthetic materials. During HD, blood is pumped into the top of the cartridge and distributed among these fibers. Simultaneously, dialysis fluid, known as dialysate, is introduced into the bottom of the cartridge, bathing the outside of the fibers. Across the semipermeable membrane,...

Hemodialysis (HD) is a medical treatment that artificially removes waste products, excess fluids, and toxins from the blood when the kidneys are no longer able to perform these functions effectively. In this process, blood is filtered through a semipermeable membrane, allowing for the selective removal of waste while preserving necessary components like blood cells and proteins. Hemodialysis is typically performed in patients with end-stage renal disease (ESRD) or severe kidney...

Diagnosing Pulmonary EmbolismDiagnosing pulmonary embolism (PE) involves clinical assessment and advanced imaging tests. The preferred diagnostic tool is the spiral (helical) CT scan or CT angiography (CTA), which uses intravenous contrast media to visualize the pulmonary vasculature and identify emboli.A ventilation-perfusion (V/Q) scan is an alternative for patients unable to receive contrast media. This scan includes both perfusion and ventilation scanning. Perfusion scanning involves...