Common Carotid Artery (Cca) Flow in Newborn Infants by Pulsed Doppler and Accuracy Estimates in Puppies

Abstract

( l 3 -19kg) were a n e s t h e t i z e d w i t h a l p h a -c h l o r a l o s e , volume v e n t i l a t e d , and a c u t e l y i n s t r u m e n t e d t o measure h e a r t r a t e ( H R ) , r i g h t a t r i a l (RAP), wedge(PAhT) , a o r t i c ( A o P ) , i n f e r i o r vena c a v a l (IVCP) , and abdominal p r e s s u r e s . AAD was accomplished by i n f l a t i n g t h e abdomen t o 20 mmHg w i t h n i t r o g e n . C a r d i a c index(C1) and BF t o h e a r t (H) , s k e l e t a l muscle(SM) , l i v e r ( L ) , and r e n a l cortex(RC) were measured by i n j e c t i n g 1 5 micron r a d i o a c t i v e m i c r o s p h e r e s i n t o t h e l e f t v e n t r i c l e .Measurements were made and u r i n e and blood c o ll e c t e d d u r i n g 30 min p r e -i n f l a t i o n and p o s t -d e f l a t i o n c o n t r o l p e r i o d s and d u r i n g 60 min of AAD. AAD markedly d e p r e s s e d C I ( 3 6 % ) * w i t h o u t a l t e r i n g HR o r AoP. RAP(43%)* and PAWP(27%)* r o s e , a s d i d pulmonary(63%)* and s y s t e m i c ( 6 6 % ) * v a s c u l a r r e s i s t a n c e s , b u t l e f t ( 2 7 % ) and r i g h t ( 2 2 % ) v e n t r i c u l a r stroke-work f e l l ; t h u s , dec r e a s e d CI d i d n o t r e s u l t from i n c r e a s e d a f t e r l o a d . CI d e c r e a s e d due t o impaired myocardial c o n t r a c t i l i t y o r , i f t r a n s m u r a l vent r i c u l a r f i l l i n g p r e s s u r e s f e l l w i t h AAD, t o d e c r e a s e d p r e l o a d . L(56%) and RC(32%)* BF f e l l more t h a n SM(3%) o r H(20%) BF. Redist r i b u t i o n of BF was n o t e x p l a i n e d by p e r f u s i o n p r e s s u r e changes. Decreased CrC1(84%) r e s u l t s , a t l e a s t i n p a r t , from d e c r e a s e d RC BE. (*p < 0.05 v s . p r e -i n f l a t i o n c o n t r o l ) ALTERATIONS IN REGIONAL BLOOD FLOW PRODUCED BY HIGH SALT DIET. A. P. Rocchlni K. P. Gallagher. (Spons. A. Rownthal). Univ. of M I C~: Ann Arbor. 200Previously we documented t h a t a hlgh salt diet (NaD) prevents f a t a l hemorrhagic shock (HS) by bluntlng the response of the renlnanglotensln-system (RAS). T o determine lf the improved survlval was associated wlth Improved tlssue perfusion, we examlned the abllity of a NaD (9 gms NaCl/day for 6 weeks) t o alter regional blood flow (BF) durlng HS. SIX dogs recelved the NaD for 6 weeks and 5 dogs recelved a normal (NO diet for 6 weeks. HS was lnduced by bleedlng Into an overhanging reservoir until the mean pressure was reduced t o 35 mmHg. Prlor t o and a t 0.5, 1.5 and 2.5 hrs of HS, BF was measured in the heart. aut (GI), and kldney uslng mlcrospheres. hrs t h e Na dogs experienced a slgniflcant and progressive IncreaseIn both GI and heart BF (~<.01). In a d d~t l o n , plasma renin activity ( 4 ) , i n 1 7 h e a l t h y t e r m and 3 p r e t e r m (30-33 wks) i n f a n t s , w i t h a PD d e v i c e (ATL, Mark IV). I n f a n t s w e r e p l a c e d on t h e i r s i d e s a n d a 7.5 MHZ t r a n sd u c e r was u s e d . The Doppler l i n e and c u r s o r w e r e...