PULMONOLOGY

Respiratory quotient = CO2 production/O2 utilization
A-a gradient = FiO2(Patm-Pbar) - (PCO2/RQ + PO2)= FiO2 (713) - (PCO2/0.8 + PO2)
A-a grad. for room air = 150 - PCO2/0.8 - PO2

NOTE--Venous blood pH measurements correlated highly with arterial pH measurements (avg. diff. .04 units) in a study of 246 pts presenting toa n ED, many of them with metabolic or respiratory derangements (Emerg. Med. J. 18:340, 2001--JW)

Acute Respiratory Distress Syndrome (ARDS)	Mechanical Ventilation
Asthma and COPD	Obstructive Sleep Apnea/Hypopnea
Bronchiolitis	Pleural Effusion
Chronic Cough	Pneumonia in Children
Croup	Pulmonary Embolus
Dyspnea	Pulmonary Hypertension
Idiopathic Pulmonary Fibrosis	Pulmonary Nodules
Inspiratory Wheeze/Stridor in Children	Spirometry
Lower Airways Dysfunction in Infants	"Stress-Induced" GI Bleeding in ICU Patients
Lung Cancer