# alveolar_PAO2_mmHg: alveolar gas equation In jackwasey/physiology: Calculate physiologic characteristics of awake and anesthetized adults, children and infants

## Description

Estimate PAO2 in alveolus based on atmospheric pressure, fraction of oxygen in inspired air, partial pressure of carbon dioxide in the alveolus, and the respiratory quotient

## Usage

 ```1 2``` ```alveolar_PAO2_mmHg(fi_o2 = 0.209, rq = 0.8, PACO2_mmHg = 40, Patm_mmHg = 760, PAH2O_mmHg = 47) ```

## Arguments

 `fi_o2` fraction of oxygen in inspired gas, from 0 to 1, default reflects (dry) room air `rq` respiratory quotient, i.e., the ratio of CO2 produced to oxygen consumed, usually between around 0.7 and 1.0, but can legitimately be greater than 1.0. Default it 0.8. `PACO2_mmHg` partial pressure of CO2 in alveolus, which can be roughly approximated as the end-tidal pCO2 `Patm_mmHg` atmospheric pressure in kPa `PAH2O_mmHg` partial pressure of water vapor at sea level, defaults to 6.25 kPa (47 mmHg) which is appropriate for body temperature

Other respiratory: `deadspace_total`
 ```1 2 3 4 5 6 7 8 9``` ```# vary RQ rq <- seq(0.6, 1.4, 0.05) plot(rq, alveolar_PAO2_mmHg(rq = rq)) # 100% fi_o2 at typical atmospheric pressure alveolar_PAO2_mmHg(fi_o2 = 1) # hyperbaric oxygen at 100%, 2 atmospheres alveolar_PAO2_mmHg(fi_o2 = 1, Patm_mmHg = 1520) ```