95. MECHANICS OF BREATmNG (Continued) 



Part VII: PULMONARY COMPLIANCE; MAN 



Two standard methods of measuring pulnnonary compliance give similar results in normal subjects. Static Method : 

 The intra- esophageal pressure upon interruption of air flow after an inspiration of 0.5 and 1.0 L, is subtracted from 

 the intra-esophageal pressure upon interruption of air flow at the end expiratory level. Compliance is expressed as 

 L/cm H^O pressure difference. D ynamic Method : The intra-esophageal pressure at the instant of zero air flow 

 after inspiration, is subtracted from the intra-esophageal pressure at the instant of zero air flow after expiration. 

 This pressure difference during normal breathing is divided into the tidal volume of that breath. The value is 

 usually expressed as an average for 5 or 10 breaths. Capacity values are for ATPS. Values in parentheses are 

 ranges and are estimate "c" of the 95% range (cf Introduction), unless otherwise indicated. 



/I/ Intra-esophageal pressure taken as equivalent to intrathoracic pressure in determining pressure differential 

 across the lung. /2/ Treadmill speed, 3 miles per hour. 



Contributors : (a) Mcllroy. M. B.. (b) Alexander. J. K., (c) Fritts, H. W., (d) Frank, N. R. 

 (f) Turino, G. M. 



(e) Radford, E. P., Jr. 



References: [ l] Cook. C. D., Sutherland, J. M., Segal. S., Cherry, R. B., Mead. J.. Mcllroy. M. B.. and Smith, 

 C. A.. J. Clin. Invest. 36:440. 1957. [2) Marshall, R.. unpublished. [3] Attinger. E. O.. Monroe. R. D., and 

 Segal, M. S.. J. Clin. Invest. 35:905. 1956. [4] Frank. N. R., Mead. J.. Siebens. A. A., and Storey, C. F., J. 

 Appl. Physiol. 9:38, 1956. [ 5Pchermack. R. M.. J. Clin. Invest. 35:394, 1956. [6] Heaf, P. J., and Prime, F. J., 

 Clin. Sc, Lond. 1^:319, 1956. [7] Stead, W. W., Fry, D. L., and Ebert, R. V., J. Laborat. Clin. M. 40:674, 1952. 

 [8l Brown. C. C. Fry. D. L., and Ebert. R. V., Am. J. M. r7:438. 1954. [9] Frank. N. R., Mead. J., and 

 Ferris, B. G., Jr., unpublished. 



Part VIU: PULMONARY COMPLIANCE VS VITAL CAPACITY: MAN 



Measurements made using the intra-esophageal balloon technique on young adults, 18-35 years old, in sitting position. 

 Values in parentheses are ranges, estimate "c" of the 95% range (cf Introduction). 



Contributor : Ebert, R. V. 



References : [ l] Frank, N. R., Mead. J., Siebens, A. A., and Storey, C. F., J. Appl. Physiol. 9:38, 1956. 



[2] Attinger, E. O.. Monroe, R. G., and Segal, M. S., J. Clin. Invest. 35:905, 1956. [3] Heaf. P. J., and Prime, 



F. J., Clin. Sc., Lond. 15:319, 1956. [4] Mead. J., and Whittenberger, J. L., J. Appl. Physiol. 5:779, 1953. 



[5] Brown, C. C, Fry, D. L., and Ebert, R. V., Am. J. M. r7:438, 1954. [6] Cherniack, R. M., J. Clin. Invest. 



35:394, 1956. (7) Stead. W. W., Fry. D. L.. and Ebert. R. V.. J. Laborat. Clin. M. 40:674, 1952. 



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