Recommendations for effective documentation in regional anesthesia: an expert panel Delphi consensus project.

Background And Objectives: Documentation is important for quality improvement, education, and research. There is currently a lack of recommendations regarding key aspects of documentation in regional anesthesia. The aim of this study was to establish recommendations for documentation in regional anesthesia.

Unusual presentation and complication of the prone position for spinal surgery.

Patient positioning for operative procedures has long been associated with perioperative complications. We present a case report of shoulder dislocation, which occurred following positioning in the prone position, and was detected by axillary artery occlusion resulting in the loss of the radial artery blood pressure line waveform. We discuss the diagnosis and consequences of this complication.

Effects of nicorandil on coronary circulation and myocardial ischemia.

The effect of the new antianginal drug, nicorandil, was studied in several models of myocardial ischemia in anesthetized dogs. In animals subjected to an acute or chronic coronary artery occlusion, nicorandil produced increases in collateral perfusion when changes in aortic pressure were minimized. In a model of irreversible ischemia, nicorandil produced a marked (50%) decrease in myocardial infarct size.

Comparative effects of nicorandil, a nicotinamide nitrate derivative, and nifedipine on myocardial reperfusion injury in dogs.

The effects of the nicotinamide nitrate compound nicorandil (SG-75) and the slow channel calcium entry blocker nifedipine on the recovery of subendocardial segment shortening (% SS) were compared with a vehicle-treated group following 30 min of left anterior descending coronary artery (LAD) occlusion and 3 h of reperfusion. Sonomicrometry was used to determine % SS in ischemic and nonischemic myocardium, and radioactive microspheres were used to determine regional myocardial blood flow. Nicorandil (100-micrograms/kg bolus followed by 25 micrograms/kg/min i.

Cardiovascular actions of a new dihydropyridine calcium antagonist, 8363-S: comparison with nifedipine and nicardipine in awake, unsedated dogs.

The systemic and coronary hemodynamic actions of a new dihydropyridine, 8363-S, were compared with nifedipine and nicardipine in conscious, instrumented dogs following intravenous and oral administration. All agents produced similar reductions in arterial and ventricular pressures and increases in heart rate, dP/dt, and coronary blood flow velocity, following intravenous infusion. Following oral administration, all agents had qualitatively similar actions; however, there was a marked difference in potency.

Beneficial actions of superoxide dismutase and catalase in stunned myocardium of dogs.

Recent evidence suggests that oxygen free radicals may partially mediate irreversible ischemia-reperfusion injury in the myocardium. In the present study, the effect of a combination of two oxygen free radical scavengers, superoxide dismutase plus catalase (SOD + CAT), on the recovery of subendocardial segment function following 15 min of coronary artery occlusion followed by 3 h of reperfusion ("stunned" myocardium) was compared with a control group in barbital-anesthetized dogs. Myocardial segment shortening (%SS) in the subendocardium of nonischemic and ischemic areas was measured by sonomicrometry and regional blood flow by radioactive microspheres.

Enhanced subendocardial perfusion distal to a flow-limiting coronary artery stenosis in dogs: comparative effects of nicorandil, a potential new antianginal agent, and nitroglycerin.

The purpose of this study was to compare the effects of nicorandil [SG-75; 2-nicotinamidoethyl nitrate (ester)] and nitroglycerin on the distribution of blood flow between subendocardium and subepicardium [endocardial/epicardial blood flow ration (endo/epi)] distal to a proximal flow-limiting coronary artery stenosis in anesthetized dogs. Myocardial blood flow distribution was determined by use of 15-micron radioactive microspheres. Various indices of reactive hyperemia (peak flow, duration, volume) and poststenotic coronary pressures were used to assess the severity of ischemia in the area distal to the stenosis.

Cardiotonic effects of anthopleurin-A (AP-A), a polypeptide from a sea anemone, in dogs with a coronary artery stenosis.

The positive inotropic effect of AP-A was studied in anesthetized dogs with a severe stenosis of the left anterior descending coronary artery. Peak positive dP/dt (mm Hg/s) and % segment shortening (%SS) were used as indices of contractile function. AP-A (1.

Effects of nicorandil, a new antianginal agent, and nifedipine on collateral blood flow in a chronic coronary occlusion model.

The effects of nicorandil and nifedipine on collateral blood flow were compared in anesthetized dogs with a well-developed collateral circulation produced by Ameroid constriction (6-8 weeks) of the left anterior descending (LAD) coronary artery. The radioactive microsphere technique was used to determine myocardial perfusion in the normal left circumflex (LC) region and in the LAD region distal to the Ameroid constrictor. Low and high doses of nicorandil (25 and 50 micrograms/kg/min) or nifedipine (1 and 3 micrograms/kg/min) were infused i.

Effects of three bradycardiac drugs on regional myocardial blood flow and function in areas distal to a total or partial coronary occlusion in dogs.

The effectiveness of three bradycardiac drugs for increasing distal coronary perfusion pressure and decreasing stenosis resistance (SR) in partially occluded vessels, and thereby for increasing collateral blood flow and segmental function (%SS) in an occluded area dependent on the stenotic vessel, was studied in anesthetized dogs. Initially, the distal portion of the left anterior descending (LAD) coronary artery was occluded followed by subsequent stenosis of the left circumflex (LC) coronary artery that supplies collateral flow to the ischemic LAD area. A decrease in LC flow (35 +/- 3 to 24 +/- 3 ml/min) and distal coronary pressure (109 +/- 4 to 47 +/- 4 mm Hg) resulted in an increase in SR (0.

Comparative effects of two slow channel calcium entry blockers, FR 34235 and nifedipine, on true coronary collateral blood flow.

The effect of a new dihydropyridine calcium entry blocker, FR 34235, on coronary collateral blood flow was compared with that of nifedipine in anesthetized dogs following acute ligation of the left anterior descending coronary artery. A special technique was used to separate true coronary collateral blood flow from overlap flow due to interdigitation of normally perfused tissue contained within the ischemic region. During infusion of doses of both agents, which produced nearly equivalent decreases (15-20 mm Hg) in mean arterial pressure, flow was significantly increased in normal myocardium; however, no change in collateral perfusion to ischemic myocardium was observed.

Transmural gradient of coronary blood flow following dihydropyridine calcium antagonists and other vasodilator drugs.

The effects of the dihydropyridine calcium antagonists, nifedipine, nitrendipine and FR 7534 on the transmural distribution of coronary blood flow (endo/epi) were compared to the structurally unrelated calcium antagonists, verapamil and diltiazem and to the non-calcium antagonist vasodilator drugs, chromonar and dipyridamole in anesthetized dogs. The increase in transmural blood flow produced by diltiazem, verapamil, chromonar and dipyridamole was equally distributed between subendocardium and subepicardium (no change in endo/epi). On the other hand, the increase in myocardial blood flow produced by the dihydropyridine calcium antagonists nifedipine, nitrendipine and FR 7534 was relatively selective for subepicardial regions resulting in a significant and dose-related decrease in endo/epi.

Effects of histamine receptor stimulation on regional myocardial blood flow.

The effect of histamine (H) and specific H1 and H2 agonists and antagonists on regional myocardial blood flow was studied in anesthetized dogs by use of tracer microspheres. Intracoronary infusion of histamine (15 and 34 micrograms/min) produced a dose-related increase in transmural myocardial blood flow (from 0.82 to 1.

Comparative effects of FR 34235, a new slow channel calcium blocker, and nifedipine on hemodynamics and myocardial oxygen consumption in the anesthetized dog.

Five doses of two dihydropyridine calcium antagonists, FR 34235 and nifedipine, were given intravenously to anesthetized dogs to determine effects on hemodynamics and myocardial oxygen balance. Both agents produced dose-related decreases in mean arterial blood pressure and tension time index with little effect on heart rate, dP/dt or myocardial contractile force except at high doses where small decreases were observed. Coronary blood flow increased markedly in the presence of both agents with a maximum increase observed at doses of 10 and 30 micrograms/kg for FR 34235 and nifedipine, respectively.

Role of autoregulation in the beneficial action of propranolol on ischemic blood flow distribution and stenosis severity in the canine myocardium.

The effect of propranolol (0.1 mg/kg i.v.

Separation of overlap and collateral perfusion of ischemic canine myocardium: important considerations in the analysis of vasodilator-induced coronary steal.

Coronary steal was studied in dogs with a left anterior descending (LAD) coronary artery occlusion by use of a special technique to exclude contamination from overlapping circulations with true collateral blood flow. Different degrees of vasodilation in nonischemic myocardium were produced by the selective coronary dilator, chromonar, at a constant heart rate and aortic blood pressure. A map of the ischemic area was made, and criteria used to identify ischemic tissue samples included: (1) all samples within the LAD perfusion area, as defined by a dye technique; (2) tissue samples with blood flows less than 25% normal area flow; (3) samples from within the central ischemic zone; and (4) tissue samples with overlap blood flow less than 2% normal area flow.

Determination of experimental myocardial infarct size.

Myocardial infarction was produced in anesthetized dogs by a 2-hr occlusion and 30-min reperfusion of the left anterior descending cornary artery. A balloon-reservoir perfusion system was used for reperfusion and delineation of perfusion bed size (area at risk) with Patent blue dye. Infarct mass was determined by a histochemical staining technique with triphenyl tetrazolium chloride.

Changes in ischemic blood flow distribution and dynamic severity of a coronary stenosis induced by beta blockade in the canine heart.

The effects of equipotent beta 1-receptor-blocking doses of propranolol, metoprolol and sotalol on distal coronary pressure, stenosis resistance and regional myocardial blood flow (endo/epi) were studied in anesthetized dogs with a severe noncircumferential stenosis of the left circumflex coronary artery. No significant differences between the three beta blockers were observed for overall hemodynamics and regional myocardial blood flow. After drug treatment, subendocardial blood flow (0.

Redistribution of myocardial blood flow distal to a dynamic coronary arterial stenosis by sympathomimetic amines: comparison of dopamine, dobutamine and isoproterenol.

The effects of dopamine, dobutamine and isoproterenol on coronary hemodynamics, severity of stenosis, distal bed resistance and transmural myocardial perfusion gradients with radioactive microspheres were studied in dogs with a mild obstruction of the left circumflex coronary artery anesthetized with morphine-chloralose. Changes in transmural blood flow were related to the ratio of the diastolic aortic pressure-time index to tension-time index (DPTI/TTI) and the ratio of the distal diastolic coronary pressure-time index to tension-time index (DDPTI/TTI). At doses of 5 microgram/kg per min, dopamine had no significant effect on DPTI/TTI, DDPTI/TTI or endocardial/epicardial flow ratio; however, dobutamine produced a slight decrease in this flow ratio and in DDPTI/TTI.

Comparison of two dihydropyridine calcium antagonists on coronary collateral blood flow in acute myocardial ischemia.

Effects of two dihydropyridine calcium antagonists on regional myocardial blood flow produced by acute ligation of the left anterior descending coronary artery were examined in the pentobarbital-anesthetized open-chest dog. Equivalent hypotensive doses of nifedipine (1.25 and 2.

Evidence for a caudal brainstem site of action for cannabinoid induced hypothermia.

delta 9-Tetrahydrocannabinol (THC), 11-hydroxy delta 9-tetrahydrocannabinol (11-OH-THC) and the synthetic dimethylheptyl analogue of THC (DMHP) were injected intracerebrally into proven chemosensitive sites in the hypothalamus of unanesthetized cats with implanted microinjection guide tubes. 100 micrograms of each compound was administered in a volume of 8 microliters. Chemosensitivity of all injection sites was established by microinjection of carbamylcholine to induce hyperthermia and tetrodotoxin to induce hypothermia.