and a subcutaneous 2 lidocaine infiltration catheters were positioned in the right atrium the pulmonary artery and the aorta the lambs were allowed to stabilize for one hour after catheter placement following this stabilization period hemodynamic regional blood flow and blood gases were measured consecutively at four time points separated by 10 minute intervals over these time intervals the lambs were given control 1 control 2 anisodamine 2 mg kg and anisodamine 5 mg kg anisodamine was at a concentration of 10 mg ml and was given as a bolus via the right atrial catheter each animal served as its own control intravascular pressures were monitored with statham p23db pressure transducers and recorded on the electronics for medicine dr12 recorder regional blood flow was measured with 15 u00b1 5 u03bcm radiolabeled microspheres according to the techniques used in s einzig et al 34 acute effects of amrinone on regional myocardial and systemic blood flow distribution in the dog 34 can j physiol pharmacol 60 811 818 1982 the microspheres were injected through the left atrial catheter while the reference blood samples were withdrawn from the aorta at a rate of 3 5 ml min for a period of two minutes at the end of the experiment the animals were sacrificed by an overdose of pentobarbital tissue samples were taken from 100 different locations on each animal and blood flow was determined using standard techniques as discussed in s einzig acute effects of amrinone supra blood oxygen contents were measured with a lex 02 con machine available from.