Cardiovascular consequences of the concomitant administration of nifedipine and magnesium sulfate in pigs.

There is concern regarding the interaction of magnesium sulfate and nifedipine used concomitantly in obstetrical patients, because both are calcium channel antagonists and may induce myocardial depression as well as peripheral vasodilatation. The objective of this study was to determine the hemodynamic consequences of concomitant administration of nifedipine and magnesium sulfate in anesthetized pigs. Twelve pigs were anesthetized with sodium pentobarbital, intubated mechanically ventilated.

Milrinone is superior to epinephrine as treatment of myocardial depression due to ropivacaine in pigs.

Purpose: To determine whether milrinone is more effective than epinephrine in the resuscitation of ropivacaine induced cardiotoxicity in pigs.

Methods: Arterial, pulmonary, and LVdP/dt catheters were placed in 12 anesthetized, intubated and mechanically ventilated pigs. They received ropivacaine iv to cardiovascular toxicity: 50% decrease in LVdP/dt, cardiac output and mean arterial pressure (MAP).

Role of zatebradine and propranolol in attenuation of tachycardia produced by dobutamine in pigs.

Background: Zatebradine is a new specific bradycardiac agent that selectively slows the depolarization in the pacemaker cells of the sinoatrial node. The purpose of our investigation was to determine whether the tachycardia induced by dobutamine can be attenuated by the administration of zatebradine. The results were compared with those produced by propranolol, which is used in the treatment of sinus tachycardia.

Intraoperative pulmonary oedema in a young cocaine smoker.

This is a case of a 28-yr-old man who underwent general anaesthesia for emergency repair of a right lid laceration and lacrimal apparatus. Following induction of anaesthesia and local nasal application of phenylephrine (0.25%) he developed transient elevation of blood pressure, which was treated immediately with labetalol.

Arrhythmogenic potential of dopexamine hydrochloride during halothane anaesthesia in dogs.

Dopexamine hydrochloride (Dopacard) is the novel synthetic catecholamine designed for use in the acute management of a low cardiac output status. In addition to dopaminergic receptor stimulation, dopexamine hydrochloride is a potent beta 2 adrenoceptor agonist with negligible direct beta 1 and no alpha adrenergic effect. The objective of this study was to compare the arrhythmogenic effects of dopexamine hydrochloride and dopamine in dogs anaesthetized with halothane (1.

Role of adenosine in the diagnosis and treatment of postoperative supraventricular tachyarrhythmias.

Adenosine (Adenocard) has a potent but very transient negative dromotropic effect on atrioventricular (A-V) nodal conduction. By slowing A-V nodal conduction, adenosine may interrupt a re-entry pathway causing paroxysmal supraventricular tachycardia or facilitate the diagnosis of other supraventricular tachycardia (SVT) by exposing the underlying atrial activity. We report 15 postoperative cases in which adenosine was used to clarify the diagnosis of postoperative SVT, and allowed the appropriate postoperative care.

A comparison of esmolol and labetalol for the treatment of perioperative hypertension in geriatric ambulatory surgical patients.

This is an open randomized study comparing the efficacy and safety of i.v. esmolol and labetalol in the treatment of perioperative hypertension in ambulatory surgery.

Esmolol prevents and suppresses arrhythmias during halothane anaesthesia in dogs.

The antiarrhythmic effect of esmolol, a selective beta 1 adrenoreceptor blocker, was evaluated in the presence of epinephrine induced arrhythmias in dogs (n = 6). The arrhythmogenic dose of epinephrine (ADE) during 1.2 MAC halothane in dogs was increased from 3.

Evaluation of oxygen saturation monitoring by pulse oximetry in neonates in the delivery system.

The pulse oximeter was evaluated for use in neonates in the delivery room. One hundred neonates, delivered vaginally or by Caesarean section with general or epidural anaesthesia, were studied. After delivery, pulse oximetry probes were placed simultaneously on the ulnar side of the right hand and on the right Achilles tendon to determine whether there was a difference in arterial oxygenation (SpO2).

The effects of intravenous cimetidine and metoclopramide on gastric pH and volume in outpatients.

Study Objective: To evaluate and compare the preinduction effects of intravenously (IV) administered cimetidine alone and combined with metoclopramide on gastric contents and postoperative nausea and vomiting in outpatients undergoing elective surgery.

Design: Patients were allocated randomly to 4 groups with 20 patients in each group.

Setting: Ambulatory surgery at a university-affiliated city hospital.

Hemodynamic effects of verapamil during fentanyl-nitrous oxide anesthesia.

The hemodynamic effects of a verapamil infusion were investigated in six dogs given fentanyl-nitrous oxide anesthesia. Verapamil, 0.2 mg/kg, was given followed by an infusion of 3, 6, and 9 micrograms/kg per minute, which produced plasma verapamil concentrations ranging from 98 to 204 ng/ml.

Cardiovascular effects of a nifedipine infusion during fentanyl-nitrous oxide anesthesia in dogs.

The hemodynamic effects of a nifedipine infusion were investigated in eight dogs given fentanyl/pancuronium/nitrous oxide/oxygen anesthesia. Nifedipine (20 micrograms/kg) was given intravenously over two minutes immediately prior to each 30-minute infusion at 2 micrograms/kg/min, 4 micrograms/kg/min, and 6 micrograms/kg/min. The range of plasma nifedipine levels obtained was 52.

Comparative hemodynamic effects of labetalol and hydralazine in the treatment of postoperative hypertension.

The antihypertensive efficacy and safety of IV labetalol were evaluated and compared with the efficacy and safety of IV hydralazine in the treatment of postoperative hypertension. Twenty patients undergoing major noncardiac surgery were entered into the study. Patients were randomized and treated for postoperative hypertension with either labetalol (n = 10) or hydralazine (n = 10).

Reversal of the adverse cardiovascular effects of intravenous diltiazem in anesthetized dogs.

Intravenous diltiazem can be used to treat myocardial ischemia, hypertension, and supraventricular dysrhythmias, but significant adverse effects including atrioventricular block and hypotension have been reported. At the present time, there is controversy as to which drug is most effective in reversing these sequelae. This study was designed to assess the effectiveness of calcium chloride v epinephrine in reversing these side effects.

Haemodynamic effects of diltiazem during fentanyl-nitrous oxide anaesthesia. An in vivo study in the dog.

The haemodynamic effects of diltiazem were studied in six dogs during fentanyl-nitrous oxide (in oxygen) anaesthesia. A bolus of diltiazem 300 micrograms kg-1 was given, followed by infusions at 30, 60 and 90 micrograms kg-1 min-1 which produced plasma diltiazem concentrations of 392 +/- 30, 908 +/- 54 and 1483 +/- 134 ng ml-1, respectively. Diltiazem significantly reduced systemic vascular resistance index, mean arterial pressure, heart rate and PR interval.

Ketamine-diazepam anaesthesia in a patient with carcinoid syndrome.

The use of ketamine in patients with carcinoid syndrome is controversial because of the catecholamine response to this agent. Prior administration of diazepam modifies the catecholamine response to ketamine and may make its use in such patients safe. The successful use of a diazepam-ketamine technique for anaesthesia of a patient with malignant carcinoid syndrome and associated tricuspid valve disease who underwent laparotomy and hepatic artery ligation is described.

Sympathetic nervous system tonicity and post-coronary artery bypass hypertension.

To elucidate the pathogenesis of hypertension following coronary bypass surgery, blood pressure and plasma catecholamine concentration were measured in 28 patients with coronary artery disease who were undergoing myocardial revascularization procedures. Measurements were obtained on arrival in the operating room and 1 and 4 h after surgery. One hour after surgery, plasma norepinephrine (NE) increased significantly by 495 +/- 108 pg/ml (P less than 0.

Anaesthetic considerations in the prolonged Q-T interval (LQTS): a case report.

A case of prolonged Q-T interval syndrome (LQTS) with ventricular dysrhythmias is presented. The patient was unresponsive to medical treatment. Left stellate ganglion block, followed by surgical excision of the ganglion, resulted in reversion to normal sinus rhythm.