PULMONARY ARTERY DASTOLC PRESSURE: TS RELATON- SHP TO PULMONARY ARTEROLAR RESSTANCE AND PULMONARY "CAPLLARY" PRESSURE1 By NOBLE FOWLER, JR,2 RCHARD N WESTCOTT,3 AND RALPH C SCOTT (From the Crdic Lbortory, Cincinnti Generl Hospitl, Deprtment of nternl Medicine, College of Medicine, University of Cincinnti, Cincinnti, ) (Submitted for publiction August 2, 1951; ccepted October 15, 1951) n the systemic circultion, one ordinrily my ssume incresed peripherl resistnce when the distolic pressure is elevted (1) t is the purpose of this pper to scertin whether similr reltionship exists within the lesser circultion of mn MATERAL Subjects were selected t rndom from the medicl wrds of the Cincinnti Generl Hospitl Some were norml convlescents; others were suffering from vrious types of hert nd lung disese (Tble ) Stisfctory dt were obtined in 5 ptients METHOD Subjects were studied in the fsting condition, sedted by 1 or 2 gm of seconl Ctheterition of the right side of the hert ws done s described previously (2) Pulmonry "cpillry" pressure ws obtined by the method of Hellems nd co-workers (3) The criteri of stisfctory pulmonry "cpillry" pressures were 1) the nture of the pressure curve, showing "" nd "c" wves; 2) the peripherl loction of the ctheter; nd 3) the securing of blood sturted with oxygen from the wedged ctheter tip n some instnces no blood could be obtined from the wedged ctheter n the mjority of instnces double lumen ctheter ws used, so tht pulmonry rtery nd pulmonry "cpillry" pressures could be recorded simultneously n some instnces, single lumen ctheter ws employed; in these cses pulmonry "cpillry" pressure ws recorded first; then the ctheter tip ws quickly withdrwn into the proximl portion of the pulmonry rtery so tht lmost simultneous recording of the pulmonry rtery pressure could be mde Recordings of pressures were 1 This study ws supported by Reserch Contrct V11 M-32 from the Veterns Administrtion 2 portion of this work ws ccomplished during the tenure of Reserch Fellowship sponsored by the West Virgini Hert Assocition, n ffilite of the Americn Hert Assocition 3 Public Helth Service Postdoctorte Reserch Fellow of the Ntionl Hert nstitute Present ddress: Clevelnd Clinic Foundtion, Clevelnd, mde with the Hthwy blood pressure recording pprtus Crdic outputs were determined by the direct Fick method s outlined before (2) Mixed venous smples were obtined from the proximl portion of the pulmonry rtery Duplicte smples of expired ir were nlyed for CO, nd 2 nd required to check within 3% Duplicte blood smples, obtined during the collection of expired ir, were nlyed for 2 on the Vn Slyke mnometric pprtus nd required to check within 2 vol % Resting crdic outputs were obtined fter the ctheter hd been in plce 15 to 3 minutes or more mmeditely fter tking blood nd gs smples for the output, pressure recordings were mde Men pulmonry rtery nd pulmonry "cpillry" pressures were determined by plnimetry Mesurements were mde over two or more respirtory cycles A point 1 cm bove the tble on which the subject ly ws tken s the ero point in pressure mesurements Pulmonry rteriolr resistnce ws clculted from the formul PA - PC R = co X 1,332, where R = rteriolr resistnce in dynes sec/cm', PA = men pulmonry rtery pressure, mm Hg, PC = men pulmonry "cpillry" pressure, mm Hg, CO = crdic output in cc/sec RESULTS These re shown in Tble nd Figures 1 through 7 n Figure 1 is shown sctter digrm plotted logrithmiclly indicting the observed reltionship between pulmonry rtery distolic pressure nd pulmonry rteriolr resistnce The correltion () between the two ws high (r=92; p=<1) n Figures 2 nd 3 re logrithmic grphs indicting the reltionships between pulmonry rteriolr resistnce nd pulmonry rtery systolic nd men pressures t is noteworthy tht even closer correltion ws found here The correltion coefficient of resistnce nd systolic pressure ws 95 (p = < 1); the 72
PULMONARY ARTERY DASTOLC PRESSURE 73 TABLE Pulmonry rtery Crdic output, Pulmonry pressure, mm Hg L/min Pulmnry men resistnce, % of cpcity pressure, Systolic/ dynes sec1tl -l mm Hg Men distolic index Totl dnesc/m cpillry- rteriolr Arteril st, 1 B M (F, 57) 9 29 38/17 27 397 81 Bronchiectsis 2 W (F, 29) 18 25 37/15 33 9 11 92 Post-prtum myocrdosis 3 M C (M, 73) 1 13 22/ 23 35 78 859 Norml S J (M,?8) 1 25 3/2 23 5 22 97 HCVD, no filure 5 C C (M, ) 12 17 25/11 28 5 7 9,3 Norml (conv empyem) J S (M, 75) 22 2 39/22 2 3 89 935 Hypertension 7 J B (M, 3) 15 2 3/21 27 2 22 9 Crcinom of lung 8 B (M, 37) 7 15 2/9 32 55 1 89 Conv pneumoni 9 J H (M, 2) 1 19/9 25 52 11 85 Hypertension 1 G A (M, 59) 18 5 1/35 29 9 52 755 Cor Pulmonle, diphrgmtic herni 11 N J (M, 22) 1 1 22/8 33 55 57 99 Conv rheum fever 12 N M (F, 2) 7 17 2/11 2 1 29 91 Rheumtoid rthritis 13 A H (F, 5) 8 17 3/11 8 9 13 91 HCVD 1 C P (M, 3) 11 18 25/13 25 7 11 951 Conv pneumoni 15 M S (M, 9) 23 5 7/3 2 37 85 Mitrl stenosis 1 M B (M, ) 7 18 27/1 23 2 213 91 HCVD, Silicosis 17 P S (M, 3) 1 18/7 37 59 85 993 Mlnutrition 18 J R (M, 3) 1 23/9 3 55 12 898 Conv pneumoni 19 W B (M, 37) 7 13 21/9 5 8 2 89 Conv pleurisy 2 C M (M, 9) 7 18 2/9 3 51 17 93 Rheumtoid rthritis 21 J S (M, 39) 7 19 32/1 2 8 189 783 Hemoptysis? cuse 22 L J (M, 2) 1 27 3/21 3 73 133 927 Fibrosis lung 23 L A (M, 3) 9 1 2/9 3 79 7 931 Neuritis, mlnutrition 2 V H (M, 27) 1 15/ 32 51 9 95 Epilepsy, lung bscess 25 E B (F, 28) 22 32 3/25 1 99 87 8 Beri-beri 2 H H (M, 39) 9 15 1/7 3 9 83 95 Bulbr pr72 27 F H (F, 38) 7 1 23/1 5 7 93 923 Nutritionl cirrhosis 28 G Y (M, ) 11 17 2/13 23 3 113 91 Conv, pneumoni 29 C F (M, 5) 15 2 37/18 19 32 217 9 Conv pneumo3i2 3 H P (M, 8) 1 23/11 3 5 12 91 CNS lues 31 C H (F, 9) 8 2 23/1 3 58 1 93 Presis 32 S M (M, ) 7 1 21/9 31 52 11 95 Conv pneumoni
7 NOBLE FOWLER, JR, RCHARD N WESTCOTT, AND RALPH C SCOTT TABLE (Continued) 33 E J (M, 3) Norml hert, chronic leukemi 3 M L (F, 52) Emphysem 35 F B (F, 2) Sickle cell nemi 3 R J (M, 9) Pneumoconiosis 37 F J (M, ) HCVD, LMCA, thrombosis 38 M (M, 39) HCVD, filure 39 A B (M, ) Comp HCVD, lues, optic trophy G A (M, ) Cor pulmonle 1 R (M, 31) Mitrl stenosis 2 C G (M, ) Norml hert, frontl lobe trophy 3 W E (M, 5) Crcinom lung, multiple myotoni J M (M,?7) Pneumoni, crcinom lung 5 E M (M, 37) Presis G Y (M, 8) Norml 7 F T (M, 52) Metsttic crcinom lung 8 J S (M, 52) Emphysem 9 J B (M, 53) 1 Emphysem, cor pulmonle 5 R M (M, 5) Presis, luetic A 51 H F (M, 3) Silicosis,?pulmonry fibrosis 52 H W (M, ) LMCA, thrombosis 53 H S (M, 51) Emphysem 5 C D (M, 2) Eisenmenger's tetrlogy Pulmonry rtery Crdic output, Pulmonry pressure, mm Hg Llmin Pulmonry cenilr rterlolr Arteril Os st, pressure, ~ ~ ~ ~ ~ -resistnce, % Of mm Hg Men Systolic/ c%'iy ndex Totl does sec/cm 7 13 7 11 17 12 19 19 1 8 1 9 12 8 11 S 9 1 21 19 17 23 35 22 7 29 1 35 12 18 17 25 2 3 1 29 12 32 12 distolic~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2/12 3/1 25/1 3/1 3/12 5/29 3/1 119/51 5/18 23/7 52/28 22/7 2/9 2/8 3/1 28/15 55/2 25/1 53/19 2/8 /17 1/8 33 2 5 21 21 15 39 18 23 3 37 3 3 7 33 21 32 23 22 22 32 22 5 3 8 3 2 2 78 33 39 55 59 57 1 89 5 37 55 2 2 33 8 2 113 337 5 223 21 593 12 1331 211 12 25 53 98 1 27 223 321 11 351 15 15 179 937 893 83 891 97 99 95 552 98 919 737 98 9 922 91 925 781 1 9 959 85 88 correltion coefficient for resistnce nd men pressure ws 9 (p = < 1) When pulmonry "cpillry" pressure ws plotted ginst pulmonry rteriolr resistnce on logrithmic grph (Figure ), no significnt correltion ws found (r = 23; p = > 5) n Figure 5, pulmonry rteriolr resistnce is plotted ginst rteril oxygen sturtion on semilogrithmic pper A significnt negtive correltion ws found (r -5; p = < 1) Correltion between pulmonry rtery distolic pressure nd pulmonry "cpillry" pressure ws determined nd is shown on semilogrithmic pper (Figure ) A significnt correltion ws observed (r = 5; p = < 1) No significnt correltion between rteril oxygen sturtion nd crdic output ws observed (Figure 7; r = 7; p = > 9)
lc cx - PULMONARY ARTERY DASTOLC PRESSURE CORRELATON BETWEEN PULMONARY ARTEROLAR RESSTANCE AND PULMONARY ARTERY DASTOLC PRESSURE 22 Lo * 1 *o ** S * - 8 A * - 5- t w 1 lo: 5- ~ :r e 7 E w 5o- % so U) - 1-3- - w i 2 * UPPER LMT OF NORMAL 75 r * 92 - V C 2 3 51 2 3 1 2 PULMONARY ARTEROLAR RESSTANCE DYNES SEC /CM-5 FG 1 ob 2 i w - ) 2 : CORRELATON BETWEEN PULMONARY ARTEROLAR RESSTANCE AND PULMONARY ARTERY SYSTOLC PRESSURE l-j w A 1 8 @L >- w 5- Ot ' 3 @ * go OF NORMAl # r -j 2~~~~~~ in~~~~~~ UPPER LMT r 95 1 2 3 5 1 2 3 5 1 2 DSCUSSON t hs been suggested tht the elevtion of pulmonry rtery distolic pressure commonly seen in emphysem is reflection of the incresed pulmonry vsculr resistnce found in tht condition PULMONARY ARTEROLAR RESSTANCE DYNES SEC /CM-5 FG 2 (5) Although this my well be true, it would pper from our dt tht it would be dngerous to predict rteriolr resistnce from the pulmonry rtery distolic pressure Although high degree of correltion is shown between pulmonry
7 resistnce with norml distolic pressure dition, n even higher degree of correltion with pulmonry rteriolr resistnce ws found with regrd to pulmonry rtery men pressure nd pul- ~~* NOBLE FOWLER, JR, RCHARD N WESTCOTT, AND RALPH C SCOTT CORRELATON BETWEEN PULMONARY ARTEROLAR RESSTANCE AND PULMONARY ARTERY MEAN PRESSURE - -i oi E U D 1 U) X) 8- so 7-5 2 - ' 3- * _ - 1~ GC- > 2 UPPER LMT W" OF NORMAL *: * ' r-o9 *, 1 1 2 3 5 7 1 2 3 1 2 PULMONARY ARTEROLAR RESSTANCE DYNES SEC /CM-5 FG 3 n d- RELATON BETWEEN PULMONARY ARTEROLAR RESSTANCE AND PULMONARY CAPLLARYU PRESSURE X co 3 CL x ~~~ E 2C ~! 5 * { UPPER LMT Uf) D-*"* o OF NORMAL l t E _ F rtery distolic pressure nd pulmonry rteriolr resistnce, there is considerble sctter; furthermore, eight ptients hd norml resistnce with high distolic pressure nd seven ptients hd high monry rtery systolic pressure thn with regrd to the pulmonry distolic pressure t must be borne in mind tht the pulmonry rtery pressure depends upon crdic output nd left tril pressure s well s pulmonry vsculr resistnce One would interpret the bove findings to indicte tht rise in pulmonry rteriolr resistnce increses the pulmonry rtery pressure, nd tht o: to23 l D 2 3 5 K)O 2 3 5 1 2 PUJLMONARY ARTEROLAR RESSTANCE DYNES SEC/CM-'5 F
2 bc 1C CORRELATON BETWEEN PULMONARY ARTEROLAR RESSTANCE AND ARTERAL OXYGEN SATURATON 1 2- en 5C1- Z C so 8 3C o - 2C - : ; UPPER LMT OF NORMAL PULMONARY ARTERY DASTOLC PRESSURE 2-1 1 * * )O S; 1 ~~~~~~~~~~~~~ O 1 5- re-5 3 5 7 8 9 ARTERAL OXYGEN SATURATON PER CENT OF CAPACTY FG 5 the increse is s gret or greter in the men nd systolic pressures thn in the distolic n view of the sttement tht rise in left tril pressure would be expected to produce n increse in pulmonry rtery distolic pressure (), the significnt correltion observed between this pressure nd' pulmonry "cpillry" pressure is of interest since the ltter is considered to vry with left tril pressure There ws firly wide rnge of sctter here, however t is lso importnt to note tht in only seven of the 5 subjects did pulmonry "cpillry" pressure exceed the pulmonry rtery distolic pressure Even in these instnces the differences were smll nd could be explined by the error of the experimentl method The filure to find correltion between the height of pulmonry "cpillry" pressure nd the mount of pulmonry rteriolr resistnce does not necessrily conflict with the observtions of Dexter (7), since our dt contin no pulmonry "cpillry" pressures bove 25 mm Hg t which level protective constriction of the pulmonry rteries is presumed to occur in order to prevent pulmonry oedem 1 The finding of significnt negtive correltion between rteril oxygen sturtion nd pulmonry rteriolr resistnce is of interest, in view of the evidence tht hypoxi produces pulmonry rtery vso-constriction (, 8) We believe, however, tht these dt lone would not necessrily permit one to drw tht conclusion Correltion nd custion re not the sme t is likely tht conditions such s pulmonry emphysem which re commonly ssocited with rteril hypoxi produce pulmonry rteril hypertension through mechnism of which hypoxi is but prt Our filure to find correltion between crdic output nd rteril oxygen sturtion is in greement with the observtions of Borden nd coworkers (5) who found no evidence of such correltion in 2 cses of emphysem, but is in disgreement with some theories s to the cuse of high crdic output in cor pulmonlel () One should not conclude, however, tht our results necessrily indicte no reltion between crdic output nd hypoxi in emphysem, since our dt were ob- CORRELATON BETWEEN PULMONARY ARTERY DASTOLC PRESSURE AND PULMONARY ACAPLLARY" PRESSURE n (m CE C,j J EE 1t c>-ob E 1 8-5 - 3-8- - - 3 2- *- * * -ge * _ * * r -5 5 1 15 2 PULMONARY CAPLLARY" PRESSURE mm Hg FG 77 25
78 NOBLE FOWLER, JR, RCHARD N WESTCOTT, AND RALPH C SCOTT CORRELATON BETWEEN CARDAC NDEX AND ARTERAL OXYGEN SATURATON 95 * * * O 9 U e8 - Lj o * *o C : 75 to 7- x 5' ' r 7 K-- :5:5 15 2 25 3 35 5 CARDAC NDEX - LTERS/ MNUTE FG 7 5 55 5 tined from ptients suffering from vriety of hert diseses Unlike the hert in emphysem, the herts in some of our subjects would be unble to respond to stress sitution by n increse in output SUMMARY A study of pulmonry rteriolr resistnce, pulmonry rtery systolic, distolic, nd men pressures, nd pulmonry "cpillry" pressure ws mde in 5 humn subjects, some norml nd some suffering from vriety of diseses Significnt correltion ws found between pulmonry rteriolr resistnce nd ech of the following: pulmonry rtery systolic, men, nd distolic pressures The correltion of resistnce with distolic pressure ws no closer thn with men or systolic pressure A significnt negtive correltion between pulmonry rteriolr resistnce nd rteril oxygen sturtion ws found Significnt correltion between, pulmonry "cpillry" pressure nd pulmonry rtery distolic pressure ws observed No significnt correltion ws found between rteril oxygen unsturtion nd crdic output t is concluded tht n increse in pulmonry rteriolr resistnce produces n elevtion in pulmonry rtery men, systolic, nd distolic pressures There is no evidence tht incresed resistnce produces disproportionte elevtion in pulmonry distolic pressure s compred to men nd systolic pressures REFERENCES 1 Best, C H, nd Tylor, N B, The Physiologicl Bsis of Medicl Prctice: A Text in Applied Physiology Willims & Wilkins Co, Bltimore, 195, Ed 5 2 Fowler, N, Westcott, R N, Scott, R C, nd McGuire, J, The effect of nor-epinephrine upon pulmonry rteriolr resistnce in mn J Clin nvest, 1951, 3, 517 3 Hellems, H K, Hynes, F W, Dexter, L, nd Kinney, T D, Pulmonry "cpillry" pressure in nimls estimted by venous nd rteril ctheterition Am J Physiol, 198, 155, 98
Fisher, R A, Sttisticl Methods for Reserch Workers Oliver & Boyd, London, 195, Ed 11 5 Borden, C W, Wilson, R H, Ebert, R V, nd Wells, H S, Pulmonry hypertension in chronic pulmonry emphysem Am J Med, 195, 8, 71 Cournnd, A, Some spects of the pulmonry circultion in norml mn nd in chronic crdiopulmonry diseses Circultion, 195, 2, 1 PULMONARY ARTERY DASTOLC PRESSURE 79 7 Dexter, L, Pulmonry circultory dynmics in helth nd disese, t rest Bull N E Med Center, 199, 11, 2 8 Westcott, R N, Fowler, N O, Scott, R C, Huenstein, V D, nd McGuire, J, Anoxi nd humn pulmonry vsculr resistnce J Clin nvest, 1951, 3, 957