TITLE

Hypotension and Arteriovenous Shunting: Effects of Intravenous Infusion of Nitroprusside, Nitroglycerin and Phentolamine

AUTHOR(S)
Dumont, Louis; Lamoureux, Claudette; Lelorier, Jacques; Stanley, Paul; Chartrand, Claude
PUB. DATE
February 1984
SOURCE
Angiology;Feb1984, Vol. 35 Issue 2, p88
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The effects of nitroprusside, nitroglycerin and phentolamine on cardiac dynamics and on the fraction of cardiac output shunted through systemic arteriovenous communications, which may explain disparate responses elicited by these systemic vasodilators upon venous return, have been studied in 15 nonanesthetized dogs. Cardiac dynamic parameters were measured by electromagnetic flow probe placed at the root of the aorta. Quantitative measurements of total systemic arteriovenous shunting were determined from the fraction of 9,μ radioactively labeled microspheres, injected into the left atrium, recovered in the pulmonary artery. To provide a common basis for comparison, the mean arterial pressure was lowered by 15-20% either with an intravenous infusion of nitroprusside, nitroglycerin or phentolamine. At the fifteenth minute of infusion, nitroprusside produced significant decrease in stroke volume index (23%) and left ventricular power and work (28% and 40%). Nitroglycerin decreased significantly stroke volume index (12%), cardiac index (9%) and left ventricular work (22%). Phentolamine significantly increased heart rate (72%) and left ventricular maximum acceleration (30%) while it decreased stroke volume index (41%), left ventricular power and work (19% and 55%). Total peripheral resistance was significantly affected only. by infusion of phentolamine (-18%). Left ventricular maximum velocity, mean systolic ejection rate and maximum systolic flow did not change significantly under infusion of these systemic vasodilators. Under control conditions, total systemic shunting of cardiac output averaged 8.9- 10% and was not modified by any of the vasodilators used. Arteriovenous O&sub2; difference and oxygen consumption, corroborated these findings since they remained within normal limits before and after infusion of nitroprusside, nitroglycerin or phentolamine. These results indicate that the mechanisms by which venous return is altered during administration of systemic vasodilators in normal subjects are not related to shunting of blood via peripheral arteriovenous anastomoses.
ACCESSION #
16352674

 

Related Articles

  • HOW VASODILATORS BACKFIRE (and when to expect it). de Toledo, Laura Worthington // RN;Jul82, Vol. 45 Issue 7, p41 

    Discusses the effects of vasodilators sodium nitroprusside and nitroglycerin on the systemic circulatory system and pulmonary circulation. Details on how vasodilators reduce the workload of the heart and lower myocardial oxygen consumption; Changes brought by vasodilators to the blood gas;...

  • Reactivity of Arterial Vessels during Antiorthostasis and Systemic Hypotension. Balueva, T.; Sergeev, I. // Bulletin of Experimental Biology & Medicine;Mar2010, Vol. 149 Issue 3, p298 

    In experiments on rats, changes in blood pressure and cardiac output in response to antiorthostatic (head-down) tilt 15° and 45° were examined under conditions of decreased arterial tone induced by sodium nitroprusside. The decrease in initial systemic blood pressure to 90 mm Hg attenuated...

  • DIRECT-ACTING PARENTERAL VASODILATORS.  // RN;Feb91, Vol. 54 Issue 2, p30 

    Presents information on two direct-acting parenteral vasodilators. Diazoxide; Sodium nitroprusside.

  • Sodium Nitroprusside in Anaestesia.  // British Medical Journal;6/7/1975, Vol. 2 Issue 5970, p524 

    Focuses on the effectiveness of sodium nitroprusside (SNP) as a hypotensive agent in Great Britain. Clinical features of induced hypotension; Chemical composition of SNP; Dosage recommended.

  • Vasodilators.  // Cardiovascular Pharmacology Manual;2008, p5 

    The article presents information about several vasodilators, they include nitroglycerin and nitroprusside. Some of the diseases treated by these vasolidators are hypertensive crisis, myocardial infarction and cardiogenic shock. Their adverse events include headache, dizziness, tachycardia and...

  • WHAT TO WATCH OUT FOR WITH emergency antihypertensives. Kirschenbaum, Harold L.; Rosenberg, Jack M. // RN;Sep83, Vol. 46 Issue 9, p53 

    Provides information on several antihypertensives. Diazoxide; Trimethaphan; Sodium nitroprusside.

  • Non-invasive cardiac output monitoring during sinus surgery. Gollapudy, Suneeta; Riess, Matthias // Journal of Anesthesia;Aug2015, Vol. 29 Issue 4, p639 

    A letter to the editor is presented in response to the article "Comparison of the hemodynamic effects of nitroprusside and remifentanil for controlled hypotension during endoscopic sinus surgery" by So Hui Yun, Jeong Hong Kim and Hyun Jung Kim, that was published in the previous issue.

  • In reply: Non-invasive cardiac output monitoring during sinus surgery. Yun, So; Kim, Hyun // Journal of Anesthesia;Aug2015, Vol. 29 Issue 4, p640 

    A reply from the authors of the article "Comparison of the hemodynamic effects of nitroprusside and remifentanil for controlled hypotension during endoscopic sinus surgery" in the previous issue is presented.

  • Different Approaches to the Treatment of Ergotism: A Review of Three Cases. Husum, Bent; Berthelsen, Preben; Metz, Peter; Rasmussen, Jens Peter // Angiology;Sep1980, Vol. 31 Issue 9, p650 

    Describes consecutive cases of ergotism which were treated according to different suggestions in the literature. Treatment consisting of a sympathetic block by means of a continuous lumbar epidural block; Continuous infusion of sodium nitroprusside; Treatment with continuous intravenous infusion...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics