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Clinical significance and diseases of the Lungs

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The lungs are prone to infectious diseases. Tuberculosis is a serious infectious disease of the lung as is bacterial pneumonia.

Pulmonary fibrosis is a condition that can prove fatal.

The lung tissue is replaced by fibrous connective tissue which causes irreversible lung scarring.

Lung cancer can often be incurable. Also cancers in other parts of the body can be spread via the bloodstream and end up in the lungs where the malignant cells can metastasise.

A pulmonary embolism is a blood clot that becomes lodged in the lung.

Respiratory diseases

Respiratory surgery. Mechanical ventilation. Medical uses[edit] Respiratory therapist examining a mechanically ventilated patient on an Intensive Care Unit.

Mechanical ventilation

Mechanical ventilation is indicated when the patient's spontaneous ventilation is inadequate to maintain life. It is also indicated as prophylaxis for imminent collapse of other physiologic functions, or ineffective gas exchange in the lungs. Because mechanical ventilation serves only to provide assistance for breathing and does not cure a disease, the patient's underlying condition should be correctable and should resolve over time.

In addition, other factors must be taken into consideration because mechanical ventilation is not without its complications (see below) Common medical indications for use include: Associated risk[edit] Barotrauma — Pulmonary barotrauma is a well-known complication of positive-pressure mechanical ventilation.[2] This includes pneumothorax, subcutaneous emphysema, pneumomediastinum, and pneumoperitoneum.[2] Lung volumes. Lung volumes and lung capacities refer to the volume of air associated with different phases of the respiratory cycle.

Lung volumes

Lung volumes are directly measured; Lung capacities are inferred from lung volumes. The average total lung capacity of an DIGGDS adult human male is about 6 litres of air,[1] but only a small amount of this capacity is used during normal breathing. The lung capacity of freediver and world record holder Herbert Nitsch is measured to be 10 Liters, which he can expand to 15 Liters with a special technique called “packing” or “buccal pumping”.

Tidal breathing is normal, resting breathing; the tidal volume is the volume of air that is inhaled or exhaled in only a single such breath. The average human respiratory rate is 30-60 breaths per minute at birth,[2] decreasing to 12-20 breaths per minute in adults.[3] Pulmonology. Pulmonology is a medical specialty that deals with diseases involving the respiratory tract.[1] The term is derived from the Latin word pulmō, pulmonis ("lung") and the Greek -λογία, -logia.


Pulmonology is synonymous with pneumology (from the Greek πνεύμων ("lung") and -λογία, -logia), respirology and respiratory medicine. Pulmonology is known as chest medicine and respiratory medicine in some countries and areas. Pulmonology is considered a branch of internal medicine, and is related to intensive care medicine. Pulmonology often involves managing patients who need life support and mechanical ventilation. Pulmonologists are specially trained in diseases and conditions of the chest, particularly pneumonia, asthma, tuberculosis, emphysema, and complicated chest infections. Variations in nomenclature[edit] Diagnosis[edit] The pulmonologist begins the diagnostic process with a general review focusing on: Physical diagnostics are as important as in the other fields of medicine.

Liquid breathing. Perfluorochemical (perfluorocarbon) molecules have very different structures that impart different physical properties such as respiratory gas solubility, density, viscosity, vapor pressure, and lipid solubility.[1] Thus, it is critical to select the appropriate PFC for a specific biomedical application, such as liquid ventilation, drug delivery or blood substitutes.

Liquid breathing

The physical properties of PFC liquids vary substantially; however, the one common property is their high solubility for respiratory gases. In fact, these liquids carry more oxygen and carbon dioxide than blood.[2] In theory, liquid breathing could assist in the treatment of patients with severe pulmonary or cardiac trauma, especially in pediatric cases. Liquid breathing has also been proposed for use in deep diving[3][4] and space travel.[5] Despite some recent advances in liquid ventilation, a standard mode of application has not been established yet.

Drowning. Drowning is defined as respiratory impairment from being in or under a liquid.[1] It is further classified as by outcome into: death, ongoing health problems and no ongoing health problems.[1] Using the term near drowning to refer to those who survive is no longer recommended.[1] It occurs more frequently in males and the young.[2] Drowning itself is quick and silent, although it may be preceded by distress which is more visible.[3] A person drowning is unable to shout or call for help, or seek attention, as they cannot obtain enough air.


The instinctive drowning response is the final set of autonomic reactions in the 20 – 60 seconds before sinking underwater, and to the untrained eye can look similar to calm safe behavior.[3][4] Lifeguards and other persons trained in rescue learn to recognize drowning people by watching for these instinctive movements.[3]