PULMONARY FUNCTION TESTING 
OF UNANESTHETIZED BEAGLE DOGS 
J. L. Mauderly and J. A. Pickrell" 
ABSTRACT 
Methods for testing pulmonary function were 
adapted for use on unanesthetized, unsedated Beagle 
dogs used for studying the effects of inhaled radio- 
nuclides. A test apparatus, face mask, and restraining 
device designed in this laboratory were used for per- 
forming comprehensive studies of pulmonary function of 
untrained dogs. 
Ventilation was characterized by measuring respira- 
tory frequency, tidal volume, and minute volume. The 
open circuit nitrogen washout method used for measur- 
ing functional residual capacity also gave indices of in- 
trapulmonary gas distribution such as nitrogen clear- 
ance curves and the lung clearance index. Elastic and 
flow resistive properties of the lung tissue and airways 
were evaluated by tests of dynamic pulmonary compli- 
ance and resistance. 
Steady state carbon monoxide diffusing capacity was 
calculated using alveolar gas tensions obtained by an 
automatic, volume controlled end tidal sampler. Gas 
exchange was further characterized by measuring the 
alveolar-arterial gradients for oxygen and carbon diox- 
ide. Oxygen saturation and acid-base parameters were 
calculated from femoral arterial samples. Parameters 
calculated from measurements of expired gas collected 
during arterial bleeding included oxygen uptake, carbon 
dioxide elimination, alveolar ventilation, effective venti- 
lation, and alveolar deadspace ventilation. 
Tests of lung function during treadmill exercise were 
used to detect subclinical lung damage. Respiratory fre- 
quency, tidal volume, minute volume, gas exchange, 
and specific ventilation were measured while dogs ran 
at 3.0 and 4.5 mph. 
Normal values are reported for adult Beagles. 
INTRODUCTION* 
A laboratory designed to evaluate the pul- 
monary function of Beagle dogs has been devel- 
oped as part of an AEC-sponsored inhalation 
toxicology program. Measurements are made to 
study the quantitative and qualitative relation- 
* Fission Product Inhalation Laboratories Lovelace Foundation 
for Medical Education and Research Albuquerque, New Mexico 
87108. 
** Research performed under U.S. Atomic Energy Commission 
Contract AT (29-2) -101 3. 
ships between inhalation exposure to various 
radioactive aerosols and the resulting biological 
effects. Previous reports^"° have indicated the 
usefulness of the dog as an experimental model 
for investigations of the effects of external 
thoracic irradiation on pulmonary function. 
Measurements, however, were performed with 
the dog under anesthesia. In order to minimize 
the risk involved in testing dogs committed to 
lifespan studies, and to utilize methods of test- 
ing similar to those used in human pulmonary 
function laboratories, procedures were devel- 
oped which could be applied without the use of 
anesthetics. This paper describes the pulmonary 
function testing methods currently used in our 
laboratory and gives normal values that have 
been obtained for parameters routinely meas- 
ured. The procedures are performed without 
anesthesia or sedation, and, with the exception of 
those involving treadmill exercise, are per- 
formed on untrained dogs. 
METHODS 
All of the parameters reported, except those 
obtained during exercise, are measured using 
an apparatus (Figure 1) fabricated in the labo- 
ratory from readily available components. The 
dogs respire through a low-resistance, low- 
deadspace breathing valve (No. 1400, Hans Ru- 
dolph Inc., Kansas City, Mo.). A system of me- 
chanical and solenoid valves allows inspiration 
of a choice of gas mixtures and expiration into 
a laboratory exhaust line, a 30-liter Douglas 
bag (Warren E. Collins, Inc., Braintree, 
Mass.), or a 120-liter spirometer (Collins). The 
dry volume of expirate collected in the Douglas 
bag is measured by passing the gas through a 
drying cannister and dry gas meter (American 
Meter Co., Boston, Mass.). A system of valves 
allows sampling and analysis of respired gases 
665 
