- Email: [email protected]
Effect of the application of venous tourniquets on blood volume
Effect of the Application Tourniquets PHILIP SAMET, M.D., F.A.c.c.,
of Venous
on Blood Volume*
WILLIAM H. BERNSTEIN, M.D., F.A.C.C. and ROBERT J. BOUCEK, M.D. Miami
Beach,
B
Florida
after injection ; the data were plotted on semilogarithmic paper to permit extrapolation to the zero time of injection. Arterial samples for T-1824 and P3* analysis were also drawn ten and twenty minutes after release of the tourniquets and plotted on the same semilogarithmic scale employed for plotting the data obtained during application of the tourniquets. Rotating tourniquets were employed in twentyfive studies (Table IIA). The tourniquets were automatically rotated every ten minutes so that tourniquets were applied to any one extremity for thirty of each forty minute period. In twenty-three studies (Table IIB) nonrotating tourniquets were applied to three of the four extremities for periods of time and pressure levels indicated in Table I.
LOODLESS PHLEBOTOMY by means of rotating tourniquets applied to the extremities is commonly employed in the therapy of acute left ventricular failure. Experimental evidence that this procedure results in an altered blood volume is limited to five patients.’ The purpose of this study is to investigate the effect of venous tourniquets on plasma volume and red cell mass in a large group of subjects. METHODS AND MATERIALS Forty-eight studies were performed in forty-three subjects. The vital statistics and diagnoses are listed in Table I. Most subjects were patients with cardiac disease who had previously had cardiac failure and were receiving digitalis and diuretics. A few had heart failure at the time of study. Some patients were studied more than once. No patient had pulmonary edema at the time of study. Red cell mass and plasma volume were determined by P32and T-1824 as previously described.* All patients were in the postabsorptive state after an overnight fast. Initial determinations of plasma volume and red cell mass were made after at least two hours in the supine position. Venous tourniquets were applied by wrapping five inch wide standard blood pressure cuffs about the upper thighs and arms as close to the trunk as possible. The cuffs were inflated to levels 5 to 10 mm. Hg below the diastolic arterial pressure levels. The duration of application of the venous tourniquets is listed in Table I. Repeated measurements of plasma volume and red cell mass were made via second (intraarterial) injections of Pa2 and T-1824 during the last thirty minutes of the indicated periods of tourniquet application. These latter values were corrected for the volumes of red cell and plasma volume removed during the first blood volume determination. All samples for T-l 824 and radioactive phosphorus determination were drawn via a Cournand indwelling arterial needle ten, twenty and thirty minutes
RESULTS The data in the two groups listed in Tables IIA and IIB.
of patients
are
ROTATINGTOURNIQUETS The average initial plasma volume totaled 2,746 ml. (Table IIA). After application of rotating tourniquets, the uncorrected and corrected corresponding values were 2,663 and 2,745 ml., respectively. There is a statistically significant difference between the first two mean values (2,746 and 2,663 ml.) (P < 0.01, 95 per cent confidence limits -25 to - 141 ml.). The first and third mean plasma volumes (2,746 and 2,745 ml.) are not significantly different (1 > P > 0.9, 95 per cent confidence limits +56 to -58 ml.). The corresponding red cell mass data were 1,660 (control), 1.540 (uncorrected) and 1,592 (corrected) ml., respectively. There is a statistically significant difference between the first two means ( P< 0.001, 95 per cent confidence limits -78 to -161 ml.), and between the first and third means (P < 0.01, 95 per cent
* From the Cardio-Pulmonary Laboratory and the Department of Medicine, Mount Sinai Hospital, Miami Beach, and the Section of Cardiology of the Department of Medicine, University of Miami School of Medicine, Coral Gables, Florida. Supported by a research grant from the National Heart Institute [H-2436 (C3)] and from the Heart Association of Greater Miami. SEPTEMBER1961
369
Samet,
370
Bernstein
and Boucek
TABLE I Diagnoses and Rotating Tourniquet
Data
-
Case
No.
Age (YES.) and Sex
Tourniquet
Body Surface Area
Diagnosis*
Duratior
(sq. M.)
_-
_ 1 2 3A B C 4 5 6A B 7 8 9 IO 11 12 13 14 15 16A B 17A B 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
50, M 60, M 48, M
55, F 51, F 59, F 40, F 66, M 32, F
44, F 52, F
34, 41, 50, 48, 39,
M F
F F F
34, M 54, M 63, M 43, M 38, M 39, F 38, M 49, M 48, M 35, M 41, M 26, F 48, M 52, M 58, M 46, M 73, M 60, M 62, M 50, M 46, M 54, M 74, M 21, F 27, F 33, F 41, F
! /
i
I
1.89 1.61 1.80 1.81 1.80 1.61 1.77 1.56 1.52 1.61 1.67 1.53 1.56 1.55 1.90 1.61 1.77 1.58 1.45 1.43 2.01 2.01 1.28 1.32 1.73 1.94 1.45 1.73 2.00 2.08 2.22 1.76 1.53 2.05 1.86 2.18 1.67 1 81 1.97 1.51 1.84 1.72 1.63 1.63 1.94 1.54 1.46 1.52
Pressure t (mm. Hg)
(hrs.) Rh HD, EH, MS, AF, CHF, IllE As HD, car pulmonale, EH, AF, CHF, IllD Cor pulmonale, EH, NSR, IIIC (In failure during study 3B) Rh HD, EH, MI, NSR, CHF, IIID Rh HD, EH, MI, MS, AF, IIIC Cong HD, EH, IA defect, AF, CHF, IllC Rh HD, EH, MS, NSR, IB Rh HD, EH, AS, Al, NSR, IllC Rh HD, EH, MS, AI, AS, NSR, IIC Idiopathic dilation, pul art, 1A Rh HD, EH, MI, MS, NSR, IIIC Rh HD, EH, MS, Ml, NSR, IB Rh HD, EH, TS, MS, Ml, AF, 11lC Rh HD, EH, MI, MS, Al, AF, IIIC
31/2 3112 3’12 1213 1 21/s 3 11/2 1
60 60 60 65 70
(R) (R) (R) (R) (NR)
60 60 75 45
(R) (R) (R) (NR)
l’/z 2 I’lz 11/2 Is/3 Ill2 1
75 (R) 65 (R) 65 (R) 65 (R) 55 (R) 70 (R) 65 (R) 50 (R) 60 (R) 60 (R) 60 CR) 65 (R) 60 (NR) 60 (R) 60 (R) 60 (R) 50 (R) 55 (R) 50 (W 60 (NR) 60 (NR) 55 (NR) 45 (NR) 60 (NR) 65 (NR) 65 (NR) 60 (NR) 50 (NR) 60 (NR) 60 (NR) 65 (NR) 65 (NR) 50 (NR) 60 (NR) 65 (NR) 60 (NR) 46 (NR) 50 (NR) 60 (NR)
1213 12/s 2 IS/, 2 1 II/* l’/% l’/l l’/Z 1213 1 1 1 1 1 11/3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Rh HD, EH, MI, MS, AF, IIIC Rh HD, EH, MS, NSR, lllc
Rh HD, EH, AS, Al, NSR, 11c Car pulmonale, EH, NSR, CHF, IIID Cor pulmonale, EH, NSR, 1IIC Rh HD, EH, MS, MI, AF, IIIC Rh HD, EH, MI, MS, AI, IPIC Rh HD, EH, AI, AS, NSR, IIC Cong HD, EH, duct-us arteriosus, NSR, IIC Carcinoma left lung Cor pulmonale, EH, NSR, IIC Rh HD, EH, MS, NSR, IB Rh HS, EH, AS, AI, NSR, 1B Rh HD, EH, MI, MS, AF, IIC Unknown HD, EH, AF, IIC Polycythemia vera Cor pulmonale, EH, NSR, 1lIC Rh HD, EH, AI, NSR, IIIC Cor pulmonale, EH, NSR, IIlC Cor pulmonale, EH, NSR, IIC Cor pulmonale, EH, NSR, IIIC Cor pulmonale, EH, ST, IIIC Rh HD, EH, AS, AI, NSR, IIC As HD, EH, NSR, LBBB, IIIC Cor pulmonale, EH, ST, IIID Norma1 Repaired IA septal defect Rh HD, EH, MS, MI, NSR, IIIC Rh HD, EH, MS, NSR, IB
-
* Rh HD =rheumatic heart disease; EH = enlarged heart ; MS = mitral stenosis; MI = mitral insufficiency; NSR = normal; AI = aortic insufficiency; IA= interatrial; AS = aortic stenosis; TS = tricuspid insufficiency; GHF = congestive heart failure; As HD = arteriosclerotic heart disease; Gong HD = congeniAF = atria1 fibrillation; tal heart disease; Unknown HD=heart disease of unknown etiology; LBBB=left bundle branch block. t R = rotating tourniquets; NR = nonrotating tourniquets.
THE
AMERICAN
JOURNAL
OF
CARDIOLOGY
Venous
Tourniquets
371
and Blood Volume
TABLE II Plasma Volume and Red Cell Mass before and during Tourniquet Plasma
Volume Analysis
Red
Cell Mass Analysis
(ml.1
Application
Arterial (X
(ml.)
A.
Rotating
Hematocrit 0.96)
Initial Determination
1 Second ’ Determi-
35 41 44 39 38 38 36 34 39 38 35 35 40 39 35 37 32 36 44 49 48 38 38 42 54 39
j
nation
Body Hematocrit
Initial Determination
~ Second Determi1 nation
Tourniquets (/our limbs)
3A B 4 5 6 7 x 9 10 11 12 13 14 15 16,~ B 17 18 19 20
4.299 3.399 3.087 3..?ll 7.‘13 3.075 3.146 I .“12 I!.‘?’ 1 2. 2.214 2.681 2.X36 3.415 2.h17 7.268 3.050
,908 DR’I
4,291 3,211 3,141 3,249 2,717 2,934 3,215 1,807 2,567 1,741 2,254 2,282 2,768 2.375 3,396 2.470 2,314 2.000 3.298 1,737 1,614 2.903 4.121 1,917 2,252 2,663
89 84 77 79 85 86 87 93 87 87 90 90 S4 87 78 80 S4 7x 78 79 73 78 71 74 78 82
4,380 3,295 3,218 3,328 2,802 3,020 3,302 1,900 2,654 1,82R 2,344 2,372 2,852 3,562 3,474 2,550 2,398 2,078 3,376 1,816 1,687 2,981 4,192 1,991 2,330 2,745
2,212 2,027 2,120 2,258 1,564 1,608 1,808 900 1,542 1,053 1,152 1,231 1,815 1.626 1,865 1,638 1,104 1.035 2,375 1,467 1,314 1,716 2,456 1,198 2,458 1,660
2,020 1,842 1,985 1,894 1,464 1,503 1,643 894 1,422 1,007 1,112 1,061 1,662 1,341 1,752 1,306 993 952 2,343 1,410 1,242 1,688 2,382 1,286 2,350 1,540
51 56 63 61 55 54 53 47 53 53 50 50 56 53 52 52 46 49 49 49 46 51 54 51 53 52
2,071 1.898 2,048 1,955 1,519 1,557 1,696 941 1,475 1,060 1,162 1,111 1,718 1,394 1,804 1,358 1,039 1,001 2,392 1.459 1.288 1,739 2,436 1,337 2,403 1,592
36 41 43 43 39 37 37 33 37 38 35 35 40 37 37 37 34 35 41 48 47 3x 41 41 53 39
3,070 3,198 3,115 3,338 2,862 3,313 2,507 2,462 3,205 2,287 3,831 2,522 3,064 3,465 2,206 2,932 2,356 2,718 2,077 2,545 2,220 2,156 1,959 2,757
2,538 1,728 2,547 2,233 2,188 2,062 1,653 1,422 2,631 2,259 2,516 1,774 3,536 1,852 1,982 2,076 1,904 2,186 1,825 1,246 1,160 1,170 869 1,973
2.307 1,567 2,555 1,996 2,205 1,960 1,473 1,278 2,621 2,139 2,595 1,556 3,161 1,719 1,806 2,079 1,754 1,917 1,650 1,157 1,079 1,100 781 1,845
47 50 54 50 47 50 51 50 47 50 51 47 50 47 50 52 50 49 54 50 49 50 48 50
2,354 1,617 2,609 2,046 2,252 2,010 1,524 1,328 2,668 2,189 2,646 1,603 3,211 1,767 1.856 2,131 1,804 1,966 1,704 1,207 1,128 1,150 829 1.896
50 2 38.2 44 8 39 6 46 3 39 8 41 8 37.6 46 6 51 1 42.0 39 S 54.0 37 5 49 8 44 3 44 3 43 5 48 8 33 6 35 5 38 0 32 8 42 5
2 7 7 4 2 6 9 5 4 0 7 9 0 8 8 3 0 9 6 1 2 0 1 6 7 8
6 3 6 0 7 4 2 2 2 7 9 6 5 5 0 0 9 6 3 0 1 9 5 5 0 8
33 9 37 ? 40 7 40 5 36 6 34 7 35.1 32 0 36.0 35 5 32 5 35 7 40 2 36 4 35 3 36 8 32 7 33 5 39 4 45 9 46 5 36 ‘I 37 ? 37 3 51 1 37 6
32 36 38 36 35 33 33 33 35 36 33 .31 37 36 14 34 30 32 41 44 43 36 36 40 51 36
0 4 7 8 0 8 8 0 6
49 5 36 4 45 2 40 3 46 2 40 3 42 2 3R 8 47 8 52 5 42 8 40 5 54 0 38 3 49 5 44.6 44 4 44 2 49 9 34 2 35 5 38 5 33 0 43 0
44.8 35 8 43.2 40.5 42 7 38 1 39 4 35 7 45 0 46 7 39 6 39 1 52 2 34 8 48 0 40 4 43 3 43 6 44 7 32 6 34 3 35 3 31 6 40 5
43.5 33 4 45 3 37.9 44.2 37 7 37 8 34 9 45 6 49 1 40 9 38 9 51 4 33 7 45 8 42 2 43 5 42 1 45 2 31 9 33 5 34 6 29 4 40 :
6
0 7 5 0 0 5 n 2 5 8 3 H 0 1 1 6
3c 68 17B 24 25 26 27 28 29 30 31 32 33 34 35 76 37 3R 39 40 41 42 43 Averaq,
3 122 31116 3.348 3.271 7.“43 3 35 7.543
3
3.242 3.475 7.147 3,059 2.487 7.liii ’ ‘14 _.-. 2,:“? 3.114 2.141 1.881 2,
hZ’3
2.995 3,120 3.081 3.260 2.788 3.235 2.427 2.384 3.124 2,209 3,751 2,442 2,989 3,387 2,135 2.853 2,2Rl 2,639 2,000 2,466 2,140 2,07x 1.888 2,680
75 7S 74 7R 74 78 80 78 RI 78 SO 80 75 78 71 79 75 79 77 79 80 78 71 77
-
-
-
-
confidence limits -27 to -108 ml.). The change in arterial hematocrit values after application of the tourniquet was not significant (1 > P > 0.9, 95 per cent confidence limits -0.60 to +0.64). The decrease in body hematocrit value was significant (0.01 > P > 0.001, 95 per cent confidence limits -0.30 to - 1.69). SEPTEMBER
1961
NONROTATING
TOURNIQUETS
The average control plasma volume equaled 2,820 ml. (Table IIB). After application of nonrotating tourniquets, the uncorrected and corrected corresponding values were 2,680 and 2,757 ml., respectively. There is a statistically significant difference between the first two
372
Samet, Bernstein and Boucek
mean values (P < 0.001, 95 per cent confidence limits -98 to -187 ml.), and between the first and third means (0.01 > P > 0.001, 95 per cent confidence limits -20 to - 109 ml.). The corresponding red cell mass data were 1,973 (control), 1,845 (uncorrected) and 1,896 (corrected) ml., respectively. There is a statistically significant difference between the first two mean values ( P < 0.001, 95 per cent confidence limits -81 to -172 ml.), and between the first and third mean values (0.01 > P > 0.001, 95 per cent confidence limits -31 to -122 ml.). The change in arterial hematocrit is of limited significance CO.02 > P > 0.01, 95 per cent confidence limits +O.OS to +0.68). No significant change in body hematocrit was noted (0.3 > P > 0.2, 95 per cent confidence limits -1.02 to +0.25). The P32 and T-1824 data obtained ten and twenty minutes after release of the tourniquets fell on the same semilogarithmic straight line extrapolation as did the points obtained during tourniquet application. COMMENTS The data obtained in the present study demonstrate a fall in red cell mass after application of both rotating and nonrotating venous tourniquets, before and after correction for the red cell mass removed between the two deterThe maximum average decrease minations. in red cell volume is about 130 ml. uncorrected for the red cell volume removed, and about 80 The maximl. after such correction is made. mum decrease in plasma volume after application of the tourniquet is 140 ml. uncorrected and 65 ml. corrected (Table IIA and B). The maximum decrease in total blood volume after the application of tourniquets is, therefore, about 270 ml. uncorrected and 145 ml. corrected (Table IIA and B). These decreases in total blood volumes constitute only about 5 per cent of the total blood volumes noted in these subjects. Seven studies (Cases 1, 2, 4, 6, 3B, 18, 6B) in six patients were performed while the subjects had heart failure. The first six such determinations were done with rotating tourniquets. The average uncorrected and corrected decrease in red cell mass was 177 and 123 ml., respectively. The average uncorrected fall in plasma volume was 62 ml. ; when corrected, the plasma volume actually increased 21 ml. The data from the single patient with heart failure studied with nonrotating tourniquets were similar (Table The blood volume alterations IIB, Case 6B).
induced by venous tourniquets are, therefore, of similar magnitude in patients with compensated and decompensated cardiac disease. Failure of the post-tourniquet release P32 and T-1824 points to fall below the straight line extrapolation of the corresponding points obtained during tourniquet application indicates that little or no P32 and T-1824 free fluid was added to the vascular bed in the posttourniquet period. These data are at variance with those obtained by Ebert and Stead.’ Employing a different experimental protocol, they found that venous tourniquets placed on three extremities at diastolic pressure levels in five patients removed 720 ml. of blood from the head, trunk and arm. This volume of blood “represented 15 per cent of the volume of blood normally circulating in the head, trunk and arm.” These observations were made employing T-l 824 to measure plasma volume; red cell mass was not measured directly. The authors concluded that “this investigation demonstrated that as much blood was removed from the general circulation by venous tourniquets as by the usual phlebotomy.” The text of their paper further states, “It is significant that a measurable amount of fluid is lost from the bloodstream during the period of venous engorgement. This is in part the More result of the increased capillary pressure. fluid would have been lost if the period of congestion had been prolonged. This loss of fluid from the bloodstream explains in part the clinical observation that in the treatment of acute left ventricular failure the beneficial effects of tourniquets persist for some time after their Their Figure 1 shows that “plasma release.” volume is decreased after the release of tourniquets and has not completely returned to norThe quanmal at the end of twenty minutes.” titative, but not qualitative, difference in the data of Ebert and Stead and those in the present study is probably due to the larger number of subjects employed in the present study. Altschule3 has reviewed the evidence relative to the hemodynamic effect of venous tourniquets. Peters4 demonstrated that there is a loss of fluid from the blood into the tissues of the limbs to which the tourniquets were applied with a consequent increase in plasma specific gravity or hemoglobin concentration. Landis3 showed that the swelling of the limb after venous congestion persisted for a time after removal of the tourniquet. The data in the present study demonstrate only a small decrease in plasma THE AMERICAN JOURNAL
OF
CARDIOLOGY
Venous
Tourniquets
volume after application of venous tourniquets. In view of the small decrements in blood volume after application of venous tourniquets noted in these forty-eight experiments, a question must be raised as to the mechanism of the clinical improvement observed in patients with acute left ventricular failure treated with venous It is unlikely that removal of even tourniquets. 250 ml. of blood could per se result in the pronounced beneficial effect of “bloodless phlebotom)-“ in patients with pulmonary edema. A decrease in cardiac output has not been uniformly observed after tourniquets were applied for venous congestion.6-g Measurements of true volume of pulmonary blood, as recently performed by Milnor, Jose and McGaff,‘O may provide a clue to the mechanism of clinical improvement. These investigators determined central blood volumes via systemic arterial sampling after injection of indocyanine green into the pulmonary artery and into the left atrium in the course of comThe bined right and left heart catheterization. difference between these two “central blood” volumes is defined as the volume of pulmonary blood. If all or most of the small decreases observed in total blood volume after application of venous tourniquets were secondary to decreases in true volume of pulmonary blood, a more satisfactory explanation for the therapeutic effect of bloodless phlebotomy would be at hand. Hamilton and Morgan” have observed that application of venous tourniquets results in an increase in vital capacity even in normal subjects in the dorsal recumbent position. Studies are planned to provide the necessary direct data of the effect of venous tourniquets on true volume of pulmonary blood. Vascular collapse with hypotension developed in several subjects treated with venous tourniquets. Other investigators2p12 have had similar experiences, pointing to the need for careful observation of the patient during the use of tourniquets. SUMMARY
Rotating and nonrotating venous tourniquets were applied to the extremities at pressure levels of 5 to 10 mm. Hg below the diastolic blood pressure in twenty-five and twenty-three studies, respectively. This procedure resulted in only modest decreases in plasma volume and red cell mass, totaling less than 5 per cent of the total blood volume. Similar results were ob-
SEPTEMBER1361
and Blood Volume
373
tained in subjects studied during congestive heart failure (but not acute pulmonary edema) and in patients with compensated cardiac disease. The physiologic mechanism responsible for the clinical improvement noted with application of venous tourniquets in acute left ventricular failure is, therefore, uncertain. Several alternative mechanisms remain to be evaluated.
REFERENCES 1. EBERT, R. V. and STEAD, E. A., JR. The effect of the application of tourniquets on the hemodynamics of the circulation. J. Clin. Invest., 19: 561, 1940. 2. SAMET, P., FRITTS, H. W., JR., FISHMAN,A. P. and COURNAND,A. The blood volume in heart disease. Medicine, 36: 211, 1957. 3. ALTSCHULE, M. D. Physiology in Disease of the Heart and Lungs, p. 321. Cambridge, 1954. Harvard University Press. 4. PETERS, J. P., JR., BULGER, G. A., EISENMAN,A. J. and LEE, C. Total acid-base equilibrium of plasma in health and disease. IV. The effects of stasis, exercise, hyperpnea, and anoxemia; and the causes of tetany. J. Biol. Chem., 67: 175, 1926. 5. LANDIS, E. M., JONAS, L., ANGEVINE,M. and ERB, W. The passage of fluid and protein through the human capillary wall during venous congestion. J. Clin. Invest., 11 : 717, 1932. 6. HOWARTH, S., MCMICHAEL, J. and SHARPEYSCHAFER, E. P. Effects of venesection in low output heart failure. Clin. SC., 6: 41, 1946. 7. FITZHUGH, F. W., JR., MCWHORTER, R. L., JR., ESTES, E. H., JR., WARREN, J. V. and MERRILL, A. J. The effect of application of tourniquets to the legs on cardiac output and renal function in normal human subjects. J. Clin. Invest., 12 : 1163, 1953. 8. WARREN, J. V., BRANNON,E. S., STEAD, E. A., JR. and MERRILL, A. J. The effect of venesection and the pooling of blood in the extremities on the atria1 pressure and cardiac output in normal subjects with observations on acute circulatory collapse in three instances. J. Clin. Invest., 24: 337, 1945. 9. JUDSON,W. E., HOLLANDER, W., HATCHER, J. D., HALPERIN, M. H. and FRIEDMAN, I. H. The cardiohemodynamic effects of venous congestion of the legs or of phlebotomy in patients with and without congestive heart failure. J. Clin. Znoest., 34: 614, 1955. 10. MILNOR, W. R., JOSE, A. D. and MCGAFF, C. J. Pulmonary vascular volume, resistance, and compliance in man. Circulation, 22: 130, 1960. 11. HAMILTON,W. F. and MORGAN, A. B. Mechanism of postural reduction in vital capacity in relation to orthopnea and storage of blood in lungs. Am. J. Physiol., 99: 526, 1932. 12. FUCHS, L. Ueber die Messung des Venendruckes und ihre klinische Bedeutung. Deutches Arch. f. klin. Med., 68: 135, 1921.
of Venous
on Blood Volume*
WILLIAM H. BERNSTEIN, M.D., F.A.C.C. and ROBERT J. BOUCEK, M.D. Miami
Beach,
B
Florida
after injection ; the data were plotted on semilogarithmic paper to permit extrapolation to the zero time of injection. Arterial samples for T-1824 and P3* analysis were also drawn ten and twenty minutes after release of the tourniquets and plotted on the same semilogarithmic scale employed for plotting the data obtained during application of the tourniquets. Rotating tourniquets were employed in twentyfive studies (Table IIA). The tourniquets were automatically rotated every ten minutes so that tourniquets were applied to any one extremity for thirty of each forty minute period. In twenty-three studies (Table IIB) nonrotating tourniquets were applied to three of the four extremities for periods of time and pressure levels indicated in Table I.
LOODLESS PHLEBOTOMY by means of rotating tourniquets applied to the extremities is commonly employed in the therapy of acute left ventricular failure. Experimental evidence that this procedure results in an altered blood volume is limited to five patients.’ The purpose of this study is to investigate the effect of venous tourniquets on plasma volume and red cell mass in a large group of subjects. METHODS AND MATERIALS Forty-eight studies were performed in forty-three subjects. The vital statistics and diagnoses are listed in Table I. Most subjects were patients with cardiac disease who had previously had cardiac failure and were receiving digitalis and diuretics. A few had heart failure at the time of study. Some patients were studied more than once. No patient had pulmonary edema at the time of study. Red cell mass and plasma volume were determined by P32and T-1824 as previously described.* All patients were in the postabsorptive state after an overnight fast. Initial determinations of plasma volume and red cell mass were made after at least two hours in the supine position. Venous tourniquets were applied by wrapping five inch wide standard blood pressure cuffs about the upper thighs and arms as close to the trunk as possible. The cuffs were inflated to levels 5 to 10 mm. Hg below the diastolic arterial pressure levels. The duration of application of the venous tourniquets is listed in Table I. Repeated measurements of plasma volume and red cell mass were made via second (intraarterial) injections of Pa2 and T-1824 during the last thirty minutes of the indicated periods of tourniquet application. These latter values were corrected for the volumes of red cell and plasma volume removed during the first blood volume determination. All samples for T-l 824 and radioactive phosphorus determination were drawn via a Cournand indwelling arterial needle ten, twenty and thirty minutes
RESULTS The data in the two groups listed in Tables IIA and IIB.
of patients
are
ROTATINGTOURNIQUETS The average initial plasma volume totaled 2,746 ml. (Table IIA). After application of rotating tourniquets, the uncorrected and corrected corresponding values were 2,663 and 2,745 ml., respectively. There is a statistically significant difference between the first two mean values (2,746 and 2,663 ml.) (P < 0.01, 95 per cent confidence limits -25 to - 141 ml.). The first and third mean plasma volumes (2,746 and 2,745 ml.) are not significantly different (1 > P > 0.9, 95 per cent confidence limits +56 to -58 ml.). The corresponding red cell mass data were 1,660 (control), 1.540 (uncorrected) and 1,592 (corrected) ml., respectively. There is a statistically significant difference between the first two means ( P< 0.001, 95 per cent confidence limits -78 to -161 ml.), and between the first and third means (P < 0.01, 95 per cent
* From the Cardio-Pulmonary Laboratory and the Department of Medicine, Mount Sinai Hospital, Miami Beach, and the Section of Cardiology of the Department of Medicine, University of Miami School of Medicine, Coral Gables, Florida. Supported by a research grant from the National Heart Institute [H-2436 (C3)] and from the Heart Association of Greater Miami. SEPTEMBER1961
369
Samet,
370
Bernstein
and Boucek
TABLE I Diagnoses and Rotating Tourniquet
Data
-
Case
No.
Age (YES.) and Sex
Tourniquet
Body Surface Area
Diagnosis*
Duratior
(sq. M.)
_-
_ 1 2 3A B C 4 5 6A B 7 8 9 IO 11 12 13 14 15 16A B 17A B 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
50, M 60, M 48, M
55, F 51, F 59, F 40, F 66, M 32, F
44, F 52, F
34, 41, 50, 48, 39,
M F
F F F
34, M 54, M 63, M 43, M 38, M 39, F 38, M 49, M 48, M 35, M 41, M 26, F 48, M 52, M 58, M 46, M 73, M 60, M 62, M 50, M 46, M 54, M 74, M 21, F 27, F 33, F 41, F
! /
i
I
1.89 1.61 1.80 1.81 1.80 1.61 1.77 1.56 1.52 1.61 1.67 1.53 1.56 1.55 1.90 1.61 1.77 1.58 1.45 1.43 2.01 2.01 1.28 1.32 1.73 1.94 1.45 1.73 2.00 2.08 2.22 1.76 1.53 2.05 1.86 2.18 1.67 1 81 1.97 1.51 1.84 1.72 1.63 1.63 1.94 1.54 1.46 1.52
Pressure t (mm. Hg)
(hrs.) Rh HD, EH, MS, AF, CHF, IllE As HD, car pulmonale, EH, AF, CHF, IllD Cor pulmonale, EH, NSR, IIIC (In failure during study 3B) Rh HD, EH, MI, NSR, CHF, IIID Rh HD, EH, MI, MS, AF, IIIC Cong HD, EH, IA defect, AF, CHF, IllC Rh HD, EH, MS, NSR, IB Rh HD, EH, AS, Al, NSR, IllC Rh HD, EH, MS, AI, AS, NSR, IIC Idiopathic dilation, pul art, 1A Rh HD, EH, MI, MS, NSR, IIIC Rh HD, EH, MS, Ml, NSR, IB Rh HD, EH, TS, MS, Ml, AF, 11lC Rh HD, EH, MI, MS, Al, AF, IIIC
31/2 3112 3’12 1213 1 21/s 3 11/2 1
60 60 60 65 70
(R) (R) (R) (R) (NR)
60 60 75 45
(R) (R) (R) (NR)
l’/z 2 I’lz 11/2 Is/3 Ill2 1
75 (R) 65 (R) 65 (R) 65 (R) 55 (R) 70 (R) 65 (R) 50 (R) 60 (R) 60 (R) 60 CR) 65 (R) 60 (NR) 60 (R) 60 (R) 60 (R) 50 (R) 55 (R) 50 (W 60 (NR) 60 (NR) 55 (NR) 45 (NR) 60 (NR) 65 (NR) 65 (NR) 60 (NR) 50 (NR) 60 (NR) 60 (NR) 65 (NR) 65 (NR) 50 (NR) 60 (NR) 65 (NR) 60 (NR) 46 (NR) 50 (NR) 60 (NR)
1213 12/s 2 IS/, 2 1 II/* l’/% l’/l l’/Z 1213 1 1 1 1 1 11/3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Rh HD, EH, MI, MS, AF, IIIC Rh HD, EH, MS, NSR, lllc
Rh HD, EH, AS, Al, NSR, 11c Car pulmonale, EH, NSR, CHF, IIID Cor pulmonale, EH, NSR, 1IIC Rh HD, EH, MS, MI, AF, IIIC Rh HD, EH, MI, MS, AI, IPIC Rh HD, EH, AI, AS, NSR, IIC Cong HD, EH, duct-us arteriosus, NSR, IIC Carcinoma left lung Cor pulmonale, EH, NSR, IIC Rh HD, EH, MS, NSR, IB Rh HS, EH, AS, AI, NSR, 1B Rh HD, EH, MI, MS, AF, IIC Unknown HD, EH, AF, IIC Polycythemia vera Cor pulmonale, EH, NSR, 1lIC Rh HD, EH, AI, NSR, IIIC Cor pulmonale, EH, NSR, IIlC Cor pulmonale, EH, NSR, IIC Cor pulmonale, EH, NSR, IIIC Cor pulmonale, EH, ST, IIIC Rh HD, EH, AS, AI, NSR, IIC As HD, EH, NSR, LBBB, IIIC Cor pulmonale, EH, ST, IIID Norma1 Repaired IA septal defect Rh HD, EH, MS, MI, NSR, IIIC Rh HD, EH, MS, NSR, IB
-
* Rh HD =rheumatic heart disease; EH = enlarged heart ; MS = mitral stenosis; MI = mitral insufficiency; NSR = normal; AI = aortic insufficiency; IA= interatrial; AS = aortic stenosis; TS = tricuspid insufficiency; GHF = congestive heart failure; As HD = arteriosclerotic heart disease; Gong HD = congeniAF = atria1 fibrillation; tal heart disease; Unknown HD=heart disease of unknown etiology; LBBB=left bundle branch block. t R = rotating tourniquets; NR = nonrotating tourniquets.
THE
AMERICAN
JOURNAL
OF
CARDIOLOGY
Venous
Tourniquets
371
and Blood Volume
TABLE II Plasma Volume and Red Cell Mass before and during Tourniquet Plasma
Volume Analysis
Red
Cell Mass Analysis
(ml.1
Application
Arterial (X
(ml.)
A.
Rotating
Hematocrit 0.96)
Initial Determination
1 Second ’ Determi-
35 41 44 39 38 38 36 34 39 38 35 35 40 39 35 37 32 36 44 49 48 38 38 42 54 39
j
nation
Body Hematocrit
Initial Determination
~ Second Determi1 nation
Tourniquets (/our limbs)
3A B 4 5 6 7 x 9 10 11 12 13 14 15 16,~ B 17 18 19 20
4.299 3.399 3.087 3..?ll 7.‘13 3.075 3.146 I .“12 I!.‘?’ 1 2. 2.214 2.681 2.X36 3.415 2.h17 7.268 3.050
,908 DR’I
4,291 3,211 3,141 3,249 2,717 2,934 3,215 1,807 2,567 1,741 2,254 2,282 2,768 2.375 3,396 2.470 2,314 2.000 3.298 1,737 1,614 2.903 4.121 1,917 2,252 2,663
89 84 77 79 85 86 87 93 87 87 90 90 S4 87 78 80 S4 7x 78 79 73 78 71 74 78 82
4,380 3,295 3,218 3,328 2,802 3,020 3,302 1,900 2,654 1,82R 2,344 2,372 2,852 3,562 3,474 2,550 2,398 2,078 3,376 1,816 1,687 2,981 4,192 1,991 2,330 2,745
2,212 2,027 2,120 2,258 1,564 1,608 1,808 900 1,542 1,053 1,152 1,231 1,815 1.626 1,865 1,638 1,104 1.035 2,375 1,467 1,314 1,716 2,456 1,198 2,458 1,660
2,020 1,842 1,985 1,894 1,464 1,503 1,643 894 1,422 1,007 1,112 1,061 1,662 1,341 1,752 1,306 993 952 2,343 1,410 1,242 1,688 2,382 1,286 2,350 1,540
51 56 63 61 55 54 53 47 53 53 50 50 56 53 52 52 46 49 49 49 46 51 54 51 53 52
2,071 1.898 2,048 1,955 1,519 1,557 1,696 941 1,475 1,060 1,162 1,111 1,718 1,394 1,804 1,358 1,039 1,001 2,392 1.459 1.288 1,739 2,436 1,337 2,403 1,592
36 41 43 43 39 37 37 33 37 38 35 35 40 37 37 37 34 35 41 48 47 3x 41 41 53 39
3,070 3,198 3,115 3,338 2,862 3,313 2,507 2,462 3,205 2,287 3,831 2,522 3,064 3,465 2,206 2,932 2,356 2,718 2,077 2,545 2,220 2,156 1,959 2,757
2,538 1,728 2,547 2,233 2,188 2,062 1,653 1,422 2,631 2,259 2,516 1,774 3,536 1,852 1,982 2,076 1,904 2,186 1,825 1,246 1,160 1,170 869 1,973
2.307 1,567 2,555 1,996 2,205 1,960 1,473 1,278 2,621 2,139 2,595 1,556 3,161 1,719 1,806 2,079 1,754 1,917 1,650 1,157 1,079 1,100 781 1,845
47 50 54 50 47 50 51 50 47 50 51 47 50 47 50 52 50 49 54 50 49 50 48 50
2,354 1,617 2,609 2,046 2,252 2,010 1,524 1,328 2,668 2,189 2,646 1,603 3,211 1,767 1.856 2,131 1,804 1,966 1,704 1,207 1,128 1,150 829 1.896
50 2 38.2 44 8 39 6 46 3 39 8 41 8 37.6 46 6 51 1 42.0 39 S 54.0 37 5 49 8 44 3 44 3 43 5 48 8 33 6 35 5 38 0 32 8 42 5
2 7 7 4 2 6 9 5 4 0 7 9 0 8 8 3 0 9 6 1 2 0 1 6 7 8
6 3 6 0 7 4 2 2 2 7 9 6 5 5 0 0 9 6 3 0 1 9 5 5 0 8
33 9 37 ? 40 7 40 5 36 6 34 7 35.1 32 0 36.0 35 5 32 5 35 7 40 2 36 4 35 3 36 8 32 7 33 5 39 4 45 9 46 5 36 ‘I 37 ? 37 3 51 1 37 6
32 36 38 36 35 33 33 33 35 36 33 .31 37 36 14 34 30 32 41 44 43 36 36 40 51 36
0 4 7 8 0 8 8 0 6
49 5 36 4 45 2 40 3 46 2 40 3 42 2 3R 8 47 8 52 5 42 8 40 5 54 0 38 3 49 5 44.6 44 4 44 2 49 9 34 2 35 5 38 5 33 0 43 0
44.8 35 8 43.2 40.5 42 7 38 1 39 4 35 7 45 0 46 7 39 6 39 1 52 2 34 8 48 0 40 4 43 3 43 6 44 7 32 6 34 3 35 3 31 6 40 5
43.5 33 4 45 3 37.9 44.2 37 7 37 8 34 9 45 6 49 1 40 9 38 9 51 4 33 7 45 8 42 2 43 5 42 1 45 2 31 9 33 5 34 6 29 4 40 :
6
0 7 5 0 0 5 n 2 5 8 3 H 0 1 1 6
3c 68 17B 24 25 26 27 28 29 30 31 32 33 34 35 76 37 3R 39 40 41 42 43 Averaq,
3 122 31116 3.348 3.271 7.“43 3 35 7.543
3
3.242 3.475 7.147 3,059 2.487 7.liii ’ ‘14 _.-. 2,:“? 3.114 2.141 1.881 2,
hZ’3
2.995 3,120 3.081 3.260 2.788 3.235 2.427 2.384 3.124 2,209 3,751 2,442 2,989 3,387 2,135 2.853 2,2Rl 2,639 2,000 2,466 2,140 2,07x 1.888 2,680
75 7S 74 7R 74 78 80 78 RI 78 SO 80 75 78 71 79 75 79 77 79 80 78 71 77
-
-
-
-
confidence limits -27 to -108 ml.). The change in arterial hematocrit values after application of the tourniquet was not significant (1 > P > 0.9, 95 per cent confidence limits -0.60 to +0.64). The decrease in body hematocrit value was significant (0.01 > P > 0.001, 95 per cent confidence limits -0.30 to - 1.69). SEPTEMBER
1961
NONROTATING
TOURNIQUETS
The average control plasma volume equaled 2,820 ml. (Table IIB). After application of nonrotating tourniquets, the uncorrected and corrected corresponding values were 2,680 and 2,757 ml., respectively. There is a statistically significant difference between the first two
372
Samet, Bernstein and Boucek
mean values (P < 0.001, 95 per cent confidence limits -98 to -187 ml.), and between the first and third means (0.01 > P > 0.001, 95 per cent confidence limits -20 to - 109 ml.). The corresponding red cell mass data were 1,973 (control), 1,845 (uncorrected) and 1,896 (corrected) ml., respectively. There is a statistically significant difference between the first two mean values ( P < 0.001, 95 per cent confidence limits -81 to -172 ml.), and between the first and third mean values (0.01 > P > 0.001, 95 per cent confidence limits -31 to -122 ml.). The change in arterial hematocrit is of limited significance CO.02 > P > 0.01, 95 per cent confidence limits +O.OS to +0.68). No significant change in body hematocrit was noted (0.3 > P > 0.2, 95 per cent confidence limits -1.02 to +0.25). The P32 and T-1824 data obtained ten and twenty minutes after release of the tourniquets fell on the same semilogarithmic straight line extrapolation as did the points obtained during tourniquet application. COMMENTS The data obtained in the present study demonstrate a fall in red cell mass after application of both rotating and nonrotating venous tourniquets, before and after correction for the red cell mass removed between the two deterThe maximum average decrease minations. in red cell volume is about 130 ml. uncorrected for the red cell volume removed, and about 80 The maximl. after such correction is made. mum decrease in plasma volume after application of the tourniquet is 140 ml. uncorrected and 65 ml. corrected (Table IIA and B). The maximum decrease in total blood volume after the application of tourniquets is, therefore, about 270 ml. uncorrected and 145 ml. corrected (Table IIA and B). These decreases in total blood volumes constitute only about 5 per cent of the total blood volumes noted in these subjects. Seven studies (Cases 1, 2, 4, 6, 3B, 18, 6B) in six patients were performed while the subjects had heart failure. The first six such determinations were done with rotating tourniquets. The average uncorrected and corrected decrease in red cell mass was 177 and 123 ml., respectively. The average uncorrected fall in plasma volume was 62 ml. ; when corrected, the plasma volume actually increased 21 ml. The data from the single patient with heart failure studied with nonrotating tourniquets were similar (Table The blood volume alterations IIB, Case 6B).
induced by venous tourniquets are, therefore, of similar magnitude in patients with compensated and decompensated cardiac disease. Failure of the post-tourniquet release P32 and T-1824 points to fall below the straight line extrapolation of the corresponding points obtained during tourniquet application indicates that little or no P32 and T-1824 free fluid was added to the vascular bed in the posttourniquet period. These data are at variance with those obtained by Ebert and Stead.’ Employing a different experimental protocol, they found that venous tourniquets placed on three extremities at diastolic pressure levels in five patients removed 720 ml. of blood from the head, trunk and arm. This volume of blood “represented 15 per cent of the volume of blood normally circulating in the head, trunk and arm.” These observations were made employing T-l 824 to measure plasma volume; red cell mass was not measured directly. The authors concluded that “this investigation demonstrated that as much blood was removed from the general circulation by venous tourniquets as by the usual phlebotomy.” The text of their paper further states, “It is significant that a measurable amount of fluid is lost from the bloodstream during the period of venous engorgement. This is in part the More result of the increased capillary pressure. fluid would have been lost if the period of congestion had been prolonged. This loss of fluid from the bloodstream explains in part the clinical observation that in the treatment of acute left ventricular failure the beneficial effects of tourniquets persist for some time after their Their Figure 1 shows that “plasma release.” volume is decreased after the release of tourniquets and has not completely returned to norThe quanmal at the end of twenty minutes.” titative, but not qualitative, difference in the data of Ebert and Stead and those in the present study is probably due to the larger number of subjects employed in the present study. Altschule3 has reviewed the evidence relative to the hemodynamic effect of venous tourniquets. Peters4 demonstrated that there is a loss of fluid from the blood into the tissues of the limbs to which the tourniquets were applied with a consequent increase in plasma specific gravity or hemoglobin concentration. Landis3 showed that the swelling of the limb after venous congestion persisted for a time after removal of the tourniquet. The data in the present study demonstrate only a small decrease in plasma THE AMERICAN JOURNAL
OF
CARDIOLOGY
Venous
Tourniquets
volume after application of venous tourniquets. In view of the small decrements in blood volume after application of venous tourniquets noted in these forty-eight experiments, a question must be raised as to the mechanism of the clinical improvement observed in patients with acute left ventricular failure treated with venous It is unlikely that removal of even tourniquets. 250 ml. of blood could per se result in the pronounced beneficial effect of “bloodless phlebotom)-“ in patients with pulmonary edema. A decrease in cardiac output has not been uniformly observed after tourniquets were applied for venous congestion.6-g Measurements of true volume of pulmonary blood, as recently performed by Milnor, Jose and McGaff,‘O may provide a clue to the mechanism of clinical improvement. These investigators determined central blood volumes via systemic arterial sampling after injection of indocyanine green into the pulmonary artery and into the left atrium in the course of comThe bined right and left heart catheterization. difference between these two “central blood” volumes is defined as the volume of pulmonary blood. If all or most of the small decreases observed in total blood volume after application of venous tourniquets were secondary to decreases in true volume of pulmonary blood, a more satisfactory explanation for the therapeutic effect of bloodless phlebotomy would be at hand. Hamilton and Morgan” have observed that application of venous tourniquets results in an increase in vital capacity even in normal subjects in the dorsal recumbent position. Studies are planned to provide the necessary direct data of the effect of venous tourniquets on true volume of pulmonary blood. Vascular collapse with hypotension developed in several subjects treated with venous tourniquets. Other investigators2p12 have had similar experiences, pointing to the need for careful observation of the patient during the use of tourniquets. SUMMARY
Rotating and nonrotating venous tourniquets were applied to the extremities at pressure levels of 5 to 10 mm. Hg below the diastolic blood pressure in twenty-five and twenty-three studies, respectively. This procedure resulted in only modest decreases in plasma volume and red cell mass, totaling less than 5 per cent of the total blood volume. Similar results were ob-
SEPTEMBER1361
and Blood Volume
373
tained in subjects studied during congestive heart failure (but not acute pulmonary edema) and in patients with compensated cardiac disease. The physiologic mechanism responsible for the clinical improvement noted with application of venous tourniquets in acute left ventricular failure is, therefore, uncertain. Several alternative mechanisms remain to be evaluated.
REFERENCES 1. EBERT, R. V. and STEAD, E. A., JR. The effect of the application of tourniquets on the hemodynamics of the circulation. J. Clin. Invest., 19: 561, 1940. 2. SAMET, P., FRITTS, H. W., JR., FISHMAN,A. P. and COURNAND,A. The blood volume in heart disease. Medicine, 36: 211, 1957. 3. ALTSCHULE, M. D. Physiology in Disease of the Heart and Lungs, p. 321. Cambridge, 1954. Harvard University Press. 4. PETERS, J. P., JR., BULGER, G. A., EISENMAN,A. J. and LEE, C. Total acid-base equilibrium of plasma in health and disease. IV. The effects of stasis, exercise, hyperpnea, and anoxemia; and the causes of tetany. J. Biol. Chem., 67: 175, 1926. 5. LANDIS, E. M., JONAS, L., ANGEVINE,M. and ERB, W. The passage of fluid and protein through the human capillary wall during venous congestion. J. Clin. Invest., 11 : 717, 1932. 6. HOWARTH, S., MCMICHAEL, J. and SHARPEYSCHAFER, E. P. Effects of venesection in low output heart failure. Clin. SC., 6: 41, 1946. 7. FITZHUGH, F. W., JR., MCWHORTER, R. L., JR., ESTES, E. H., JR., WARREN, J. V. and MERRILL, A. J. The effect of application of tourniquets to the legs on cardiac output and renal function in normal human subjects. J. Clin. Invest., 12 : 1163, 1953. 8. WARREN, J. V., BRANNON,E. S., STEAD, E. A., JR. and MERRILL, A. J. The effect of venesection and the pooling of blood in the extremities on the atria1 pressure and cardiac output in normal subjects with observations on acute circulatory collapse in three instances. J. Clin. Invest., 24: 337, 1945. 9. JUDSON,W. E., HOLLANDER, W., HATCHER, J. D., HALPERIN, M. H. and FRIEDMAN, I. H. The cardiohemodynamic effects of venous congestion of the legs or of phlebotomy in patients with and without congestive heart failure. J. Clin. Znoest., 34: 614, 1955. 10. MILNOR, W. R., JOSE, A. D. and MCGAFF, C. J. Pulmonary vascular volume, resistance, and compliance in man. Circulation, 22: 130, 1960. 11. HAMILTON,W. F. and MORGAN, A. B. Mechanism of postural reduction in vital capacity in relation to orthopnea and storage of blood in lungs. Am. J. Physiol., 99: 526, 1932. 12. FUCHS, L. Ueber die Messung des Venendruckes und ihre klinische Bedeutung. Deutches Arch. f. klin. Med., 68: 135, 1921.