Effects of sodium nitroprusside (MR7S1) and nitroglycerin on the systemic, renal, cerebral, and coronary circulation of dogs anesthetized with enflurane

Abstract

In beagle dogs anesthetized with enflurane-nitrous oxide, effects of sodium nitroprusside (SNP; MR7S1) and nitroglycerin (NTG) on hemodynamics and main organ circulation were studied to evaluate their effectiveness and safety as hypotensive agents during anesthesia. SNP (MR7S1) infusion (1-10 micrograms/kg/min) decreased arterial blood pressure in a dose-dependent manner. The hypotension was stable during the infusion. After discontinuation of infusion, the blood pressure rapidly returned to the initial level. The hypotension was associated with decreases in cardiac output and total peripheral resistance. NTG infusion (3-10 micrograms/kg/min) decreased arterial blood pressure, too, but the hypotension was less marked and not dose dependent, and the recovery was slower. Neither drug changed the heart rate. Infusion of SNP (MR7S1) and NTG did not change the hypotension induced by the injection of adenosine, SNP, and NTG. Furthermore, cerebral blood flow, cerebral oxygen consumption, and renal blood flow were unchanged during the hypotension produced by either drug. Coronary blood flow was decreased, but this was due to decreases in cardiac oxygen consumption. In conclusion, SNP (MR7S1) is superior to NTG as a hypotensive agent during anesthesia in efficacy, clear dose dependency, and rapid recovery. The hypotension induced by NTG as well as SNP (MR7S1) seems to have no undesirable effects on the circulation of important organs.

Cerebral Blood Flow Effects of the Nitric Oxide Donor, Nitroglycerin and its Drug Combinations in the Non-Human Primate Model

“…It was also shown that nitroglycerin increases local cerebral blood flow in man [27]. Furthermore, it was shown that cerebral blood flow was unchanged in beagle dogs after nitroglycerin treatment [28]. From the above and our preliminary investigation it is clear that nitroglycerine treatment regime can be of importance in the clinical situation; furthermore that nitroglycerin related increases in cerebral blood flow may be more evident through the reversal of decreased cerebral blood flow after NOS inhibition.…”

The influence of nitroglycerin and prostaglandin E1 on dynamic cerebral autoregulation in adult patients during propofol and fentanyl anaesthesia*

“…Indeed, several animal studies have suggested that nitroglycerin and prostaglandin E 1 do not significantly influence CBF. Hamaguchi et al [15] reported that nitroglycerin does not significantly change CBF and cerebral oxygen consumption in enflurane-anaesthetised dogs. Similarly, Koyama et al [16] reported that prostaglandin E 1 at a dose that decreased MAP did not significantly affect regional CBF in young rabbits.…”

Chronic infusion of dobutamine and nitroprusside in patients with end‐stage heart failure awaiting heart transplantation: safety and clinical outcome

“…The most frequent adverse event was hypotension, that careful monitoring of blood pressure and infusion rate prevented, without relevant clinical effects in individual patients. Previous studies showed that transient hypotension secondary to nitroprusside infusion have no serious effects on the circulation in vital organs [25].…”