Humidifying Capacity of the Nose

Abstract

Adequate moisture is essential for the maintenance of the normal function of the respiratory mucosa. Dehydration of the mucous blanket, which covers and protects the cilia, increases the viscosity of the secretion. Cilial activity is thus reduced and may even cease so that the cilia are destroyed. This is the reason why air humidification in the nose has received such wide attention.Methods for simultaneous recordings of rapid changes in temperature and relative humidity were devised.' Great temperature variations and inaccuracy of the measurements were found when the heat sensing elements were placed in the rhinopharynx, due to variability of the central air stream in relation to the elements. The most accurate measurements were obtained from the larynx, where the respiratory tract is narrowest from a functional aspect. In this region, intermixing and corresponding equalization of the temperature of the axial stream and of the marginal zone take place. METHOD AND MATERIALA cannula was inserted via the cricothyroid membrane, and a thermoelectric micro-psychrometer was introduced into the subglottic space through the cannula. Thermoelements were made of fine wires welded end-to-end (wire diameter 0.03 mm ). One of the thermoelements was kept moist, being hygroscopic fibers.At room conditions (23°C, relative humidity 45%) dry and wet temperature recordings were made on healthy volunteers during nasal breathing. Thereafter the subjects were suddenly exposed to cold atmosphere (-lOOC, relative humidity 50%) for ten minutes.

Ex Vivo Assessment and Validation of Water Exchange Performance of 23 Heat and Moisture Exchangers for Laryngectomized Patients

“…13,30,[33][34][35] The physiological tracheal climate during nose breathing is known for healthy volunteers and for head and neck cancer patients with a temporary tracheotomy. 29,30 As laryngectomized patients are head and neck cancer patients, the subglottic humidity value during nose breathing in this patient group (29.3 mg/L at 1 cm behind the temporary tracheostoma) 30 can be considered the target humidity value in the upper trachea of laryngectomized patients.…”

Radioisotopic Method for Measurement of Nasal Mucociliary Activity

“…19 Variations in temperature and humidity of the air in the examination room do not influence results to any appreciable degree. Smoking generally impairs mucocili¬ ary function,7·18 although no differ¬ ences on comparison with nonsmokers could be observed.6·17 This has been explained on the basis of rapid recov¬ ery of the cilia.…”

Ecogeographic variation across morphofunctional units of the human nose

“…The septum and turbinates substantially expand the surface area of the fossa, facilitating increased contact between the overlying nasal mucosa and the respiratory airstream (Yokley, 2009). Moreover, experimental evidence has shown that, unlike the oral passage, the nasal passages have the capacity to recover some heat and moisture lost through inspiration during expiration (Cole, 1954(Cole, , 1982Ingelstedt, 1956Ingelstedt, , 1970Proetz, 1953). This respiratory epithelium is particularly well-suited for heat and moisture exchange, as it possesses the highest frequency of goblet and seromucous cells in the respiratory tract, which provide an ample supply of water vapor for humidification of inspired air (Cole, 1982;Tos, 1982), and possesses extensive vasculature (e.g., Kiesselbach's and Woodruff's plexuses) which facilitates thermal transfers between the blood and air (Cauna, 1982;Lang, 1989;Scott, 1954).…”

“…This respiratory epithelium is particularly well-suited for heat and moisture exchange, as it possesses the highest frequency of goblet and seromucous cells in the respiratory tract, which provide an ample supply of water vapor for humidification of inspired air (Cole, 1982;Tos, 1982), and possesses extensive vasculature (e.g., Kiesselbach's and Woodruff's plexuses) which facilitates thermal transfers between the blood and air (Cauna, 1982;Lang, 1989;Scott, 1954). Combined, these factors largely explain why, during normal breathing, virtually all of the respiratory air passes through the nasal fossa rather than through the oral region (Ingelstedt, 1970), even though the complex airspaces of the nasal fossa produces significantly higher resistance to airflow (Drettner, 1970;Elad et al, 2008;Margaria & Cerretelli, 1968). Indeed, clinical evidence has shown that habitual oral breathing, especially in cold conditions, can lead to drying and inflammation of the mouth, pharynx, and larynx (Ingelstedt, 1956;Negus, 1958), which suggests that the oral passage is not as effective at long-term conditioning of inspiratory air as the nasal passages.…”