(Circulation. 1999;100:226-229.)
© 1999 American Heart Association, Inc.
Brief Rapid Communications |
Reversal by Vasopressin of Intractable Hypotension in the Late Phase of Hemorrhagic Shock
From the Departments of Medicine, Surgery, and Anesthesiology, Columbia University College of Physicians and Surgeons, 630 W 168th St, New York, NY 10032.
Correspondence to Donald W. Landry, MD, PhD, Director, Division of Clinical Pharmacology and Experimental Therapeutics, Columbia University, P&S Building, 10th Floor, Room 445, 630 W 168th St, New York, NY 10032.
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Abstract |
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Background—Hypovolemic shock of marked severity and duration may progress to cardiovascular collapse unresponsive to volume replacement and drug intervention. On the basis of clinical observations, we investigated the action of vasopressin in an animal model of this condition.
Methods and Results—In 7 dogs, prolonged hemorrhagic shock (mean
arterial pressure [MAP] of 
40 mm Hg) was induced
by exsanguination into a reservoir. After 30 minutes, progressive
reinfusion was needed to maintain MAP at 40 mm Hg, and by 1
hour, despite complete restoration of blood volume, the administration
of norepinephrine 3 µg · kg-1
· min-1 was required to maintain this pressure. At this
moment, administration of vasopressin 1 to 4 mU ·
kg-1 · min-1 increased MAP from 39±6
to 128±9 mm Hg (P<0.001), primarily because of
peripheral vasoconstriction. In 3 dogs subjected to similar
prolonged hemorrhagic shock, angiotensin II 180 ng ·
kg-1 · min-1 had only a marginal
effect on MAP (45±12 to 49±15 mm Hg). Plasma vasopressin was
markedly elevated during acute hemorrhage but fell from 319±66
to 29±9 pg/mL before administration of vasopressin
(P<0.01).
Conclusions—Vasopressin is a uniquely effective pressor in the irreversible phase of hemorrhagic shock unresponsive to volume replacement and catecholamine vasopressors. Vasopressin deficiency may contribute to the pathogenesis of this condition.
Key Words: vasopressin • shock • hemorrhage
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Introduction |
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Profound and prolonged hypotension due to hemorrhage may progress to shock unresponsive to volume replacement and vasoconstrictors such as norepinephrine.1 2 3 4 5 6 7 8 We recently observed a patient with bleeding esophageal varices who developed severe hypotension unresponsive to administration of volume replacement, large doses of catecholamine pressors, and compression of the esophageal varices. To facilitate hemostasis by constriction of the mesenteric vasculature, vasopressin was administered.9 This was followed immediately by a marked increase in arterial pressure. A similar observation in a second patient without cirrhosis and our previous observation that vasopressin is an effective pressor in septic shock10 suggested that vasopressin might also be effective in the late, irreversible phase of hemorrhagic shock. To test this, we induced prolonged hemorrhagic shock in the dog.
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Methods |
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Case Reports
Two patients admitted to the Medical Intensive Care Unit of Columbia-Presbyterian Medical Center for acute gastrointestinal hemorrhage were treated with vasopressin by their Attending Physicians. The reported cases are consecutive and span a period of 17 months. The study was approved by the Institutional Review Board of Columbia University.
Patient 1 was a 46-year-old woman who presented with cirrhosis,
gastrointestinal bleeding, and renal failure. Her baseline
systolic arterial pressure (SAP) was 130
mm Hg, but on admission, her SAP was 90 mm Hg. An emergency
esophagogastroduodenoscopy revealed bleeding esophageal varices, and
sclerotherapy was performed. Shortly afterward, she experienced a
second, large upper gastrointestinal hemorrhage and, as shown
in Figure 1
, her SAP declined to 45
mm Hg. Intravenous saline and blood products were
administered, and to maintain SAP at 90 mm Hg,
intravenous norepinephrine was administered and
the dose was increased as needed. However, as shown in the figure, the
pressure again declined (SAP <60 mm Hg), and
intravenous dopamine was started. Her plasma bicarbonate
fell quickly from 23 to 15 mEq/L as her arterial blood pH
decreased from 7.46 to 7.23. A Sengstocken-Blakemore tube was inserted,
and after aspiration of 500 mL of bloody gastric fluid, the
hemorrhage appeared to have ceased. Despite >4.0 L of
intravenous fluids, including normal saline (2 L), fresh
frozen plasma (10 U), platelets (6 U), and packed red blood cells
(6 U), and despite escalating doses of catecholamine
pressors (reaching a maximum of 6.7 µg ·
kg-1 · min-1 for
norepinephrine and 300 µg ·
kg-1 · min-1 for
dopamine), her SAP remained at 50 mm Hg for >60 minutes.
Intravenous vasopressin was then begun at 4 mU ·
kg-1 · min-1, and
as shown in Figure 1, within 10 minutes her SAP increased to
160 mm Hg, and catecholamine pressors were
discontinued. Administration of volume replacement was stopped, and the
dose of vasopressin was decreased to 2 mU ·
kg-1 · min-1, with
SAP remaining at 105 mm Hg. Vasopressin was discontinued
uneventfully after 26 hours of administration.
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The patient underwent placement of a transvenous intrahepatic portosystemic shunt and was discharged from the hospital 2 weeks thereafter.
Patient 2 was a 26-year-old woman with end-stage renal disease and
hypertension who was admitted for a cadaveric renal transplant. During
her second postoperative week, with her antihypertensive medications
discontinued and SAP 150 mm Hg, she had an upper
gastrointestinal hemorrhage with sustained hypotension (SAP
70 mm Hg). Intravenous administration of normal
saline (2 L) and packed red blood cells (5 U) failed to restore her
blood pressure, despite a central venous pressure (CVP) of 17
mm Hg. Intravenous norepinephrine was then
administered and progressively increased up to 2.3 µg ·
kg-1 · min-1
because of minor pressor response. During this period, her plasma
bicarbonate fell quickly from 16 to 8 mEq/L and arterial
blood pH from 7.39 to 7.00. Intravenous administration of
vasopressin was begun at 1 mU · kg-1
· min-1, and within 10 minutes, SAP rose to
130 mm Hg and norepinephrine was decreased to 0.2
µg · kg-1 ·
min-1, with SAP maintained at >110 mm Hg.
A plasma sample drawn just before administration of vasopressin showed
a vasopressin concentration10 of 5.1 pg/mL,
inappropriately low for the degree of hypotension (SAP 80
mm Hg).11 12 A subtotal gastrectomy was performed
immediately, and with the patient remaining
hemodynamically stable, vasopressin was discontinued
uneventfully after 2 hours of administration.
One week later, the patient sustained a pulmonary embolism and died after an asystolic arrest.
Experimental Hemorrhagic Shock
Mongrel dogs (27.4±0.6 kg, mean±SEM) were anesthetized
with pentobarbital, endotracheally intubated, and ventilated with room
air. A thoracotomy was performed, and an aortic flow probe (Transonic
Systems Inc) was placed at the aortic arch for cardiac output
determinations. Arterial pressure and CVP were transduced
from catheters in the femoral artery and internal jugular vein,
respectively. The irreversible phase of hemorrhagic shock was induced
by a variant of the method of Bond et al.4 6 By this
method, prolonged hypotension was induced by allowing the animal's
blood to fill a reservoir in open communication with a femoral artery
and adjusting the height of the reservoir to maintain mean
arterial pressure (MAP) at 40 mm Hg. As
illustrated in Figure 2, after a
variable period of hypovolemic hypotension, systemic vasodilation
was evidenced by the onset of passive transfer of blood from the
reservoir into the animal. Passive reuptake of the blood was extended
beyond the method of Bond et al4 6 and until 50% of
the blood in the reservoir had returned to the animal. At this time,
the remaining blood could be actively reintroduced in increments
without arterial pressure being restored, and, in fact, to
maintain MAP at 40 mm Hg, norepinephrine was soon
required. Normal saline was administered as needed to maintain CVP at
>5 mm Hg. The dose of norepinephrine was
progressively increased as needed up to 3 µg ·
kg-1 · min-1 (the
average dose administered to our patients), at which time vasopressin
was administered. Blood samples were obtained after acute
hemorrhage and immediately before vasopressin infusion for
determination of the plasma vasopressin concentration, as
described.10 All results are expressed as mean±SEM. Data
were analyzed with the paired Student's t test, and
differences were taken as significant if the t value
exceeded the critical value for the 5% level.
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Results |
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The arterial pressure response to vasopressin during the late irreversible phase of hemorrhagic shock is illustrated in the experiment shown in Figure 2A
. After volume replacement, the
infusion of norepinephrine at 3.0 µg ·
kg-1 · min-1
maintained a MAP of only 40 mm Hg. Within 5 minutes of
vasopressin infusion (4 mU · kg-1
· min-1), MAP increased to 140 mm Hg and
despite fluctuations remained >90 mm Hg for the next 50 minutes
of observation.
Figure 2B shows mean values for MAP and cardiac output in 7 dogs
in the late phase of hemorrhagic shock just before and immediately
after vasopressin administration. Despite restoration of blood volume
and administration of large doses of norepinephrine
(3.4±1.0 µg · kg-1 ·
min-1), MAP averaged 39±6 mm Hg during
the control period. Vasopressin was administered at 4 mU ·
kg-1 · min-1 (the
dose given to patient 1) in 4 dogs, and the other 3 received 1 mU
· kg-1 · min-1
(the dose given to patient 2); both doses increased MAP significantly
and to a similar degree, and the data were pooled. As shown,
vasopressin increased MAP from 39±6 to 128±9 mm Hg
(P<0.001) without significantly changing cardiac output.
The pressor effect of vasopressin was sustained during the period of
observation (1 hour), and in all cases the experiment was terminated
by design.
As expected, at the beginning of the hypotensive hemorrhage, plasma vasopressin concentration was markedly elevated (319±66 pg/mL), but before the administration of vasopressin, it fell to 29±9 pg/mL (P<0.01). Immediately before they received vasopressin, the arterial blood pH of these animals averaged 7.0±0.1 and the lactate concentration averaged 15±2 mg/dL, highlighting the severity of the shock state.
To examine whether the observed pressor effect of vasopressin was
shared by other vasoconstrictors, angiotensin II was
infused at 180 ng · kg-1 ·
min-1 (5 µg/min), a dose that markedly
increases pressure under normal conditions.13 However, in
3 dogs in the late phase of hemorrhagic shock (MAP 45±12 mm Hg
and arterial blood pH 7.1±0.1) receiving
norepinephrine 3.9±0.6 µg ·
kg-1 · min-1,
administration of angiotensin II had only a marginal effect
on MAP (49±15 mm Hg), confirming previous
observations.14
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Discussion |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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The 2 patients described had severe bleeding with prolonged and severe hypotension that could not be reversed despite volume replacement and massive doses of catecholamine pressors. Similarly, in the animal model, hypotension persisted despite restoration of the blood volume and administration of large doses of norepinephrine. Inasmuch as the late phase of hemorrhagic shock, which is unresponsive to volume replacement and catecholamine pressors, is believed to be irreversible,1 2 3 4 5 6 the observation that vasopressin is an extremely effective pressor is of considerable clinical interest.
Under normal conditions, the doses of vasopressin used have little or no pressor action,15 16 and significant elevation of plasma vasopressin due to unregulated release of hormone (ie, the syndrome of inappropriate secretion of antidiuretic hormone) does not cause hypertension.17 What, then, are the reasons for the observed pressor effect of vasopressin? Two possibilities are likely. First, in vascular smooth muscle, vasopressin can inhibit both ATP-sensitive potassium (KATP) channels18 and NO-induced accumulation of cGMP.19 We and others have shown that activation of the KATP channels contributes to the hypotension of several types20 of shock, including hemorrhagic shock.21 Furthermore, activation of NO synthesis also contributes to the hypotension of this condition.8 Thus, vasopressin inhibits vasodilator mechanisms that contribute to both hypotension and vascular hyporeactivity in the late phase of hemorrhagic shock.
A second factor likely to contribute to the particular pressor effectiveness of exogenous vasopressin in the late phase of hemorrhagic shock is inappropriately low plasma levels of the hormone, perhaps due to depletion of its secretory stores in the neurohypophysis. Such depletion has been described after powerful stimuli for release of vasopressin,22 and low plasma levels of the hormone have been reported during severe hypernatremia23 and during severe hypotension due to septic shock10 and advanced hemorrhagic shock.24 Indeed, the plasma vasopressin concentration in patient 2 was inappropriately low for the degree of hypotension,11 12 and in the experimental model, vasopressin in plasma declined as shock advanced.
The irreversible phase of hemorrhagic shock is thought to be a rare clinical entity, because management of acute hemorrhage, if effective, minimizes the severity and duration of hypotension and, if not, often results in death before restoration of circulating volume. However, all forms of shock, when advanced, can become poorly responsive to catecholamine pressors, perhaps as a result of the same pathogenetic mechanisms as those activated in the irreversible phase of hemorrhagic shock. Hence, an investigation of the effectiveness of vasopressin in their management seems warranted.
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Acknowledgments |
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We thank Qais Al-Awqati for helpful discussions and Margaret Coleman for patient secretarial help.
Received April 6, 1999; revision received May 24, 1999; accepted May 27, 1999.
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References |
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1. Shires GT III, Shires GT, Carrico CJ. Shock. In: Schwartz SI, ed. Principles of Surgery. 6th ed. New York, NY: McGraw-Hill Inc; 1994:119–138.
2. Walley KR, Wood LDM. Shock. In: Hall JB, Schmidt GA, Wood LDW, eds. Principles of Critical Care. New York NY:, McGraw-Hill Inc; 1992:1393–1416.
3. Rush BF Jr. Irreversibility in the post-transfusion phase of hemorrhagic shock. Adv Exp Med Biol. 1971;23:215–234.[Medline] [Order article via Infotrieve]
4. Bond RF, Manley ES Jr, Green HD. Cutaneous and skeletal muscle vascular responses to hemorrhage and irreversible shock. Am J Physiol. 1967;212:488–497.
5. Remington JW, Hamilton WF, Caddell HM, Boyd GH Jr, Hamilton WF Jr. Some circulatory responses to hemorrhage in the dog. Am J Physiol. 1950;161:106–115.
6. Bond RF, Johnson G III. Vascular adrenergic interactions during hemorrhagic shock. Fed Proc. 1985;44:281–289.[Medline] [Order article via Infotrieve]
7.
Mellander S, Lewis DH. Effect of
hemorrhagic shock on the reactivity of resistance and capacitance
vessels and on capillary filtration transfer in cat skeletal muscle.
Circ Res. 1963;13:105–118.
8.
Thiemermann C, Szabo C, Mitchell A, Vane JR. Vascular
hyporeactivity to vasoconstrictor agents and
hemodynamic decompensation in hemorrhagic shock is
mediated by nitric oxide. Proc Natl Acad Sci U S A. 1993;90:267–271.
9. Boyer TD. Cirrhosis of the liver and its major sequelae. In: Wyngaarden JB, Smith LH Jr, Bennett JC, eds. Cecil Textbook of Medicine. Philadelphia Pa: WB Saunders Co; 1992:786–794.
10.
Landry DW, Levin HR, Gallant EM, Ashton RC, Seo S,
D'Alessandro D, Oz MC, Oliver JA. Vasopressin deficiency contributes
to the vasodilation of septic shock. Circulation. 1997;95:1122–1125.
11. Minaker KL, Meneilly GS, Young JB, Landsberg L, Stoff JS, Robertson GL, Rowe JW. Blood pressure, pulse and neurohumoral responses to nitroprusside-induced hypotension in normotensive aging men. J Gerontol Med Sci. 1991;46:M151–M154.
12.
Schwartz J, Keil LC, Maselli J, Reid IA. Role of
vasopressin in blood pressure regulation during adrenal insufficiency.
Endocrinology. 1983;112:234–238.
13. Davis JO, Hartroft PM, Titus EO, Carpenter CCJ, Ayers CR, Spiegel HE. The role of the renin-angiotensin system in the control of aldosterone secretion. J Clin Invest. 1962;41:378–389.
14. Middleton S. The effects of renin and angiotensin during hemorrhagic hypotension and shock. Am J Physiol. 1943;141:132–137.
15. Wagner HN Jr, Braunwald E. The pressor effect of the antidiuretic principle of the posterior pituitary in orthostatic hypotension. J Clin Invest. 1956;35:1412–1418.
16. Tsai, Y-T, Lee F-Y, Lin H-C, Lee S-D, Hsia H-C, Lin W-J, Wang S-S, Lay C-S, Lai K-H, Lo K-J. Hyposensitivity to vasopressin in patients with hepatitis B-related cirrhosis during acute variceal hemorrhage. Hepatology. 1991;13:407–412.[Medline] [Order article via Infotrieve]
17. Padfield PL, Brown JJ, Lever AF, Moron JJ, Robertson JIS. Blood pressure in acute and chronic vasopressin excess. N Engl J Med. 1981;304:1067–1070.[Abstract]
18. Wakatsuki T, Nakaya Y, Inoue I. Vasopressin modulates K-channel activities of cultured smooth muscle cells from porcine coronary artery. Am J Physiol. 1992;263(Heart Circ Physiol 32):H491–H496.
19. Tetsuka T, Ando Y, Asano Y. Arginine vasopressin inhibits interleukin-1ß-stimulated nitric oxide and cyclic guanosine monophosphate production via the V1 receptor in cultured rat vascular smooth muscle cells. J Hypertens. 1997;15:627–632.[Medline] [Order article via Infotrieve]
20. Landry DW, Oliver JA. The ATP-sensitive K+ channel mediates hypotension in endotoxemia and hypoxic lactic acidosis in dog. J Clin Invest. 1992;89:2071–2074.
21. Salzman AL, Vromen A, Denenberg A, Szabo C. KATP-channel inhibition improves hemodynamics and cellular energetics in hemorrhagic shock. Am J Physiol. 1997;272(Heart Circ Physiol 41):H688–H694.
22. Negro-Vilar A, Samson WK. Dehydration-induced changes in immunoreactive vasopressin levels in specific hypothalamic structures. Brain Res. 1979;169:585–589.[Medline] [Order article via Infotrieve]
23. Cooke CR, Wall BM, Jones GV, Presley DN, Share L. Reversible vasopressin deficiency in severe hypernatremia. Am J Kidney Dis. 1993;22:44–52.[Medline] [Order article via Infotrieve]
24. Errington ML, Rocha M, Silva E Jr. The secretion and clearance of vasopressin during the development of irreversible haemorrhagic shock. Proc Physiol Soc. 1971;23:43P–45P.
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