Pattern of breathing

Cheyne-Stokes respiration Pattern of breathing with gradual increase in depth and sometimes in rate to a maximum, followed by a decrease resulting in apnea. The cycles ordinarily are 30 seconds to 2 minutes in duration, with 5 to 30 seconds of apnea. 

In general, adrenoceptor agonists are best delivered by inhalation because this results in the greatest local effect on airway smooth muscle with the least systemic toxicity. Aerosol deposition depends on the particle size, the pattern of breathing, and the geometry of the airways. Even with particles in the optimal size range of 2-5 Pm, 80-90% of the total dose of aerosol is deposited in the mouth or pharynx. Particles under 1-2 Pm remain suspended and may be exhaled. Bronchial deposition of an aerosol is increased by slow inhalation of a nearly full breath and by more than 5 seconds of breath-holding at the end of inspiration. 

Although adrenoceptor agonists may be administered by inhalation or by the oral or parenteral routes, delivery by inhalation results in the greatest local effect on airway smooth muscle with the least systemic toxicity. Aerosol deposition depends on the particle size, the pattern of breathing... 

Muir (1972) reviewed the effects of variations in the pattern of breathing upon total particle deposition and on the distribution of the deposited particles along the respiratory tract the effects are complex. Inertial deposition of particles is dependent upon the velocity of the particles and hence upon the velocity of the airstream. Sedimentation and diffusion-dependent deposition... 

Cole TJ, Cotes JE, Johnson GR, et al. 1977. Ventilation, cardiac frequency and pattern of breathing during exercise in men exposed to o-chlorobenzylidene malonitrile (CS) and ammonia gas in low concentrations. Q J Exp Physiol Cogn Med Sci. 63 341-351. 

Some investigators have tried to quantify the total dose deposited by using a controlled pattern of breathing and drug collection on filters (25) or by modifying the aerosol bolus/photometric method to quantify the dose deposited (91). 

For the same pattern of breathing, the quantity of aerosol inhaled over time is strongly dependent on the type of nebulizer utilized. As shown in Fig. 5, the AeroTech II produces aerosol at a rate approximately six times that of the Respirgard II (the difference in slopes). The plateau of each curve indicates the point at which the nebulizer runs dry and defines the amount of drug inhaled by the patient. For the AeroTech II, approximately 20% of the nebulizer charge is ultimately inhaled, versus 11% for the Respirgard II (9). 

Bruce, E.N. 1996. Temporal variations in the pattern of breathing. J. Appl. Physiol. 80 1079. 

Burgess, K. R Whitelaw, W. A. 1988. Effects of nasal cold receptors on patterns of breathing, 64 371-376. 

Rochester D. Respiratory muscle weakness, pattern of breathing, and CO2 retention in chronic obstructive pulmonary disease. Am Rev Respir Dis 1991 143 901-903. 

Javaheri S, Blum J, Kazemi H. Pattern of breathing and carbon dioxide retention in chronic obstructive lung disease. Am J Med 1981 71 228-234. 

Tobin MJ, Perez W, Guenther SM, et al. The pattern of breathing during successful and unsuccessful trials of weaning from mechanical ventilation. Am Rev Respir Dis 1986 134 1111-1118. 

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