11/04/2022
Interesting Lung Facts
->The right lung has three lobes and is larger than the left lung, which has two lobes.
->Each lung contains 274 to 790 million alveoli with the mean alveolar number being 480 million/lung,
the number correlating with the size of the lung.
->The alveoli cover a surface that measures 1,076.4 square feet (approximately ½ the size of a
tennis court).
->The lungs take in 1.3 - 2.1 gallons (5 - 8 liters) of air per minute, at rest the alveoli exhale up to 17.1 oz
or 0.3 liters of oxygen to your blood per minute.
->At the end of a deep breath, 80% of the lung volume is air, 10% is blood and the remaining 10% is
tissue.
->At the alveolar-capillary interface only one red blood cell at a time passes through the capillaries.
->From the trachea to the alveoli the airways of the lung divides 23-25 times.
->The lungs are the only organ in your body that floats on water, because the lungs contain 1 L of air
even after you've exhaled.
->The lungs only use about 5% of the oxygen that's been inhaled, the rest is exhaled, and the cycle is
repeated.
->At rest you exhale 17.5 milliliters of water/hour, but you lose about four times that when you exercise.
->On average one breaths 20,000 times per day and by the time you're 50 you have taken around 400
million breaths.
->On average people can hold their breath for 30 to 60 seconds, but there have been individuals who've
held their breath up to 14 minutes, with the world record held by Stig Severinsen who performed a free
dive and held his breath for 22 minutes.
->The lungs play a role in speech, the lungs push air out going into the trachea and the larynx and past
the vocal cords creating speech.
->The lung plays an important role in immunity--Airway epithelial cells secrete immune mediators such
as mucins, defensins, lysozyme, lactoferrin, and nitric oxide, which nonspecifically shield the lung from
microbial attack. In addition, they produce a number of mediators of inflammation including reactive
oxygen species, cytokines (TNF alpha), IL-1 beta, granulocyte/macrophage colony stimulating factor
(GM-CSF) and platelet activating factor to recruit inflammatory cells to the site of inflammation.
*Deepak J, Puttaswamy R and Krovvidi H. Non-respiratory functions of the lung. Continuing Education in
Anaesthesia, Critical Care and Pain. Vol 13, No 3, 2013.
*Matthias O et al. Am J Respir Crit Care Med, 2004
*Murray JF. The Normal Lung: The Basis for Diagnosis and Treatment of Pulmonary Disease. WB
Saunders Company, 1985.