airway resistance

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Related to airway resistance: Upper Airway Resistance Syndrome


1. opposition, or counteracting force, as opposition of a conductor to passage of electricity or other energy or substance.
2. the natural ability of a normal organism to remain unaffected by noxious agents in its environment; see also immunity.
3. in psychology or psychiatry, conscious or unconscious defenses against change, preventing repressed material from coming into awareness; they can take such forms as forgetfulness, evasions, embarrassment, mental blocks, denial, anger, superficial talk, intellectualization, or intensification of symptoms. It occurs because the blocked association or understanding would be too threatening to face at this point in the therapy; identification of what point the resistance comes at can be an important indicator of the patient's unconscious patterns.
airway resistance the opposition of the tissues of the air passages to air flow: the mouth-to-alveoli pressure difference divided by the rate of air flow. Symbol RA or RAW.
androgen resistance resistance of target organs to the action of androgens, resulting in any of a spectrum of defects from a normal male phenotype in which men have normal genitalia but infertility to complete androgen resistance in which the individual has a female phenotype. Complete androgen resistance is an extreme form of male pseudohermaphroditism in which the individual is phenotypically female but is of XY chromosomal sex; there may be rudimentary uterus and tubes, but the gonads are typically testes, which may be abdominal or inguinal in position. Called also testicular feminization and testicular feminization syndrome. Incomplete androgen resistance is any of various forms less than the complete type, manifested by a male phenotype with various degrees of ambiguous genitalia such as hypospadias and a small vaginal pouch, a hooded phallus, or a bifid scrotum that may or may not contain gonads.
drug resistance the ability of a microorganism to withstand the effects of a drug that are lethal to most members of its species.
insulin resistance see insulin resistance.
multidrug resistance (multiple drug resistance) a phenomenon seen in some malignant cell lines: cells that have developed natural resistance to a single cytotoxic compound are also resistant to structurally unrelated chemotherapy agents. Called also cross-resistance.
peripheral resistance resistance to the passage of blood through the small blood vessels, especially the arterioles.
pulmonary vascular resistance the vascular resistance of the pulmonary circulation; the difference between the mean pulmonary arterial pressure and the left atrial filling pressure divided by the cardiac output. Called also total pulmonary vascular resistance.
total peripheral resistance the vascular resistance of the systemic circulation: the difference between the mean arterial pressure and central venous pressure divided by the cardiac output.
total pulmonary resistance (total pulmonary vascular resistance) pulmonary vascular resistance.
vascular resistance the opposition to blood flow in a vascular bed; the pressure drop across the bed divided by the blood flow, conventionally expressed in peripheral resistance units. Symbol R or R.

air·way re·sis·tance

in physiology, the resistance to the flow of gases during ventilation resulting from obstruction or turbulent flow in the upper and lower airways; to be differentiated during inhalation from resistance to inflation resulting from decreases in pulmonary or thoracic compliance.

airway resistance (Raw)

a measure of the impedance to airflow through the bronchopulmonary system. It is the reciprocal of airway conductance.

airway resistance

A measure of the resistance (in cm H2O) to the flow (in L/min of air in upper airways, which results from natural recoil–resiliency of anatomic structures (oro- and nasopharynx, larynx, and nonrespiratory portions of the lungs, including the trachea, bronchi, and bronchioles). Airway resistance testing evaluates airway responsiveness, and includes provocation testing (e.g., bronchial challenge), evaluation of sites of airflow resistance or closures, and characterisation of the type of lung disease. Airway resistance is increased, either focally or globally, in asthma, COPD, and in smokers.

airway resistance

Lung physiology A measure of the resistance–in cm H2O to the flow–in L/min of air in upper airways, the result of natural recoil–resiliency of anatomic structures–oro- and nasopharynx, larynx, and nonrespiratory portions of the lungs–trachea, bronchi, and bronchioles through which air passes on the way to the alveoli; assessment of AR evaluates airway responsiveness, provocation testing–eg bronchial challenge, evaluation of sites of airflow resistance or closures, and characterization of the type of lung disease; airway resistance is ↑, either focally or globally in asthma, COPD, and smokers. See Airway responsiveness, Asthma, COPD.

air·way re·sis·tance

(ār'wā rĕ-zis'tăns)
physiology Resistance to flow of gases during ventilation due to obstruction or turbulent flow in the upper and lower airways; to be differentiated during inhalation from resistance to inflation due to decreases in pulmonary or thoracic compliance.

air·way re·sis·tance

(ār'wā rĕ-zis'tăns)
physiology Impendance to flow of gases during ventilation due to obstruction or turbulent flow in the upper and lower airways; to be differentiated during inhalation from resistance to inflation due to decreases in pulmonary or thoracic compliance.


1. the passage by which air enters and leaves the lungs.
2. a mechanical device used for securing unobstructed respiration during general anesthesia or other occasions in which the patient is not ventilating or exchanging gases properly. Includes an endotracheal tube and a tracheostomy tube.

artificial airway
endotracheal or tracheostomy tubes.
airway obstruction
in the unanesthetized animal is usually caused by vomitus or laryngeal spasm due to foreign material in the larynx. In the nonintubated anesthetized animal, it is caused by caudal displacement of the tongue and epiglottis, accumulation of mucus, saliva and blood in the pharynx or laryngeal spasm resulting from that accumulation. In the intubated animal, faulty placement or functioning of the endotracheal tube or kinking of it can cause obstruction of the airway. The signs of obstruction are deep, asphyxial respirations, struggling and great agitation in the conscious animal. Deeply anesthetized animals simply show a decline in respiratory efficiency.
airway reflexes
aid in the removal of secretions and foreign material. See also cough, sneeze.
airway resistance
the resistance to airflow through the respiratory tree and any addition to the airway, such as the endotracheal tube and connectors in a closed circuit anesthetic machine.
References in periodicals archive ?
For example, the increased airway resistance in the peripheral part of the respiratory system corresponds to a greater value of R1 (Fig.
Prior to treatment, all patients underwent simultaneous measurements of nasal cavity and intramaxillary sinus pressures, as well as measurements of mucociliary transport function and nasal airway resistance.
At IAR and LAR, tidal volume, tidal airflow, respiratory rate and specific airway resistance (sRaw) were measured by volumetric differential pressure transducer (PT5, Grass Co.
Oral appliances find their greatest success when utilized for simple snoring, upper airway resistance syndrome and mild to moderate obstructive sleep apnea.
In normal, awake subjects, the transient application of a small NEP at the onset of resting expiration does not elicit a reflex of the genioglossus or a change in the upper airway resistance (12,13).
The flow-interruption method for measuring airway resistance has been extensively tested for its reliability and was a non-invasive test for providing valuable data about respiratory functions.
Since upper airway resistance syndrome may require state-of-the-art technology for its detection, sleep-disordered breathing often remains undetected and hence ignored.
My favorite projects were validating the use of music and massage to reduce airway resistance and dyspnea in children with asthma, invalidating using ice over thick compression dressings for acute ankle injuries, and establishing an educational program worldwide to reduce the risk of skin trauma secondary to the use of medical adhesives.
With this type of breath, changes in airway resistance or lung/chest compliance will alter tidal volume (i.
Increased airway resistance and airway tissue damage occur over time.
Other topics include history and questionnaires, upper airway obstruction in snoring and upper airway resistance syndrome, surgical treatment, children, and the elderly.
In the obese adolescent/child, an increase in the amount of adipose tissue in the throat (pharyngeal fat pads), neck (increased neck circumference) and chest wall creates an increase in the upper airway resistance and an increase in the work of breathing.

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