420 
SURGERY AND TRANSPLANTATION 
Figure 3. — Photograph of portion of the facility in Figure 2. Partitions are aluminum and easily removable. The 
elevated false floors facilitate cleaning and keep the animals dry. 
turn and a consequent reduction of cardiac out- 
pu^ 6,8,9.10 addition, since the calf naturally 
lies on its sternum, postoperative infection and 
pain are more of a problem after sternotomy. 
Normothermic hemodilution using a dispos- 
able bubble dispersion oxygenator (Travenol 
6 LF) primed with 3 liters of 5% dextrose in 
distilled water and roller pumps (Sarns 3500) 
is routinely employed for CPBP in our labora- 
tories. During CPBP the lungs are statically 
inflated at 10 cm of water pressure and further 
inflated to 25-30 cm of water pressure every 
5 minutes. A single cannula is inserted via the 
right atrial appendage into the right ventricle 
for venous drainage when using a left thorocot- 
omy approach. Arterial perfusion is via a can- 
nula inserted into the descending thoracic aorta. 
This technique has worked particularly well for 
the insertion of mitral valve prostheses. 
During the insertion of the Baylor-Rice total 
orthotopic cardiac prosthesis, a right thorocot- 
omy using a 5th rib resection is used and both 
vena cavae are cannulated via the right atrium 
for venous drainage. Arterial perfusion is again 
via a single cannula in the descending thoracic 
aorta which is mobilized within the dorsal 
mediastinum. Cardiopulmonary bypass flows of 
40 to 60 cc/kg/min are routinely obtained by this 
method using approximately 54 cm of gravity 
drainage for venous return to the heart lung 
machine. Although the values are low when 
compared to other species, in our experience 
these flows are well tolerated in the calf for 
periods of up to II/2 hours. 
Other uses in experimental cardiovascular 
physiology for which the calf has been found 
particularly suitable include the application of 
chronic instrumentation to the heart and great 
