Overview :

The maximum inspiratory pressure is the highest atmospheric pressure developed during inspiration against an occluded airway. The maximum expiratory pressure is the highest pressure developed during expiration against an occluded airway.

Maximal Inspiratory Pressure (cm H2O)

predicted maximal inspiratory pressure, in cm of water for males 20 - 80 years old =

= 143 - (0.55 * (age in years))

predicted maximal inspiratory pressure, in cm of water for males 20 - 54 years old =

= 129 - (0.13 * (age in years))

predicted maximal inspiratory pressure, in cm of water for males 44 - 80 years old =

= 120 - (0.25 * (age in years))

predicted maximal inspiratory pressure, in cm of water for females 20 - 86 years old =

= 104 - (0.51 * (age in years))

predicted maximal inspiratory pressure, in cm of water for females 20 - 54 years old =

= 100 - (0.39 * (age in years))

predicted maximal inspiratory pressure, in cm of water for females 55 - 86 years old =

= 122 - (0.79 * (age in years))

Maximal Expiratory Pressure (cm H2O)

predicted maximal expiratory pressure, in cm of water for males 20 - 80 years old =

= 268 - (1.03 * (age in years))

predicted maximal expiratory pressure, in cm of water for males 20 - 54 years old =

= 229 + (0.08 * (age in years))

predicted maximal expiratory pressure, in cm of water for males 54 - 80 years old =

= 353 - (2.33 * (age in years))

predicted maximal expiratory pressure, in cm of water for females 20 - 86 years old =

= 170 - (0.53 * (age in years))

predicted maximal expiratory pressure, in cm of water for females 20 - 54 years old =

= 158 - (0.18 * (age in years))

predicted maximal expiratory pressure, in cm of water for females 55 - 86 years old =

= 210 - (1.14 * (age in years))

Black KF, Hyatt RE. Maximal respiratory pressures: normal values and relationship with age and sex. Am Rev Respir Dis. 1969; 99; 696-702

Fishman A (editor). Pulmonary Diseases and Disorders, Second Edition. McGraw-Hill Book Company. 1988. page 2481 and page 2506

Ruppel G. Manual of Pulmonary Function Tests, Sixth Edition. Mosby. 1994. pages 74-76.