The human larynx, often referred to as the voice box, is an intricate organ located in the neck. It serves as a pathway for air to enter the lungs during respiration and is an essential component of voice production.
Anatomy of the Larynx
The larynx consists of various components, including cartilage, muscles, and vocal cords. Its structure includes three large unpaired cartilages—the thyroid, cricoid, and epiglottis—and three smaller paired cartilages—the arytenoids, corniculates, and...

Botulism is a life-threatening neuroparalytic condition caused by botulinum neurotoxin, which is produced by the bacterium Clostridium botulinum, a Gram-positive, spore-forming, obligate anaerobe.In adults, the toxin enters the body in different ways: in foodborne botulism, the preformed toxin is absorbed in the intestine. In wound botulism, spores grow in injured tissue and release the toxin into the blood. Infant botulism differs mechanistically from adult forms. In infants, botulism commonly...

Poliomyelitis is caused by poliovirus, a small, non-enveloped, positive-sense RNA virus of the Picornaviridae family and Enterovirus genus. Transmission occurs primarily via the fecal-oral route, often through ingestion of contaminated water or food. The virus initially replicates in the oropharynx and intestinal mucosa, particularly in lymphoid tissues such as the tonsils, Peyer’s patches, and regional lymph nodes. Primary viremia follows, allowing dissemination throughout the body.In most...

Airway management is essential in emergency and surgical medicine, ensuring ventilation and oxygenation in patients who cannot maintain their own airway. Clinicians use a range of techniques and devices to secure the airway, depending on the patient’s condition and the clinical context. Key methods include endotracheal intubation, rapid sequence intubation (RSI), supraglottic airway devices, and advanced visualization aids. In cases where these approaches fail, surgical airway interventions are...

Depolarizing blockers act on skeletal muscle fibers' membranes and induce their depolarization. Most depolarizing blockers have two quaternary N+ atoms that bind the nicotinic acetylcholine receptors and cause neuromuscular blockade within minutes.
Succinylcholine is the most commonly used depolarizing blocker. Chemically, it constitutes two molecules of acetylcholine joined together by an acetate methyl group. They act on the receptors in the same way as acetylcholine. Because succinylcholine...

While local anesthetics are generally safe and well-tolerated, they can occasionally cause adverse effects that vary in severity. Local anesthetics can induce toxicity at two distinct levels. They can either produce local effects through direct contact with the neural elements or be absorbed into the bloodstream from the injection site, leading to systemic effects.
Once absorbed into the systemic circulation, local anesthetics can affect the organs that depend on the functioning of sodium...