P A Naess

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UNLABELLED The effects of various degrees of compression and active decompression during cardiopulmonary resuscitation were tested in a randomized cross-over-design during ventricular fibrillation in eight pigs using an automatic hydraulic chest compression device. Compared with 4/0 (compression/decompression in cm), mean carotid arterial blood flow rose by(More)
The haemodynamic effects of variations in the relative duration of the compression and active decompression (4 cm/2 cm) during active compression-decompression cardiopulmonary resuscitation (ACD-CPR), 30/70, 50/50 and 70/30, were tested in a randomized cross-over design during ventricular fibrillation in seven anaesthetized pigs (17-23 kg) using an(More)
Circulating levels of the endothelium-derived vasoconstrictor peptide endothelin-1 (ET-1) are increased in association with myocardial ischemia and infarction. The present study investigates whether ET-1 is synthesized and produced locally in the ischemic heart. Sixteen pigs were divided into three groups. In the first group, the left anterior descending(More)
The importance of nitric oxide (NO) in coronary blood flow (CBF) regulation was examined in anesthetized pigs. NO synthesis was inhibited by intracoronary infusion of NG-monomethyl-L-arginine (L-NMMA) or NG-nitro-L-arginine (L-NNA). L-NMMA (30 mumol/min) reduced CBF (Doppler flowmetry) by 16.3% (13.1-20.2%; P < 0.001) and L-NNA (30 mumol/min) by 16.1%(More)
Nitric oxide plays an important role in the regulation of basal renal blood flow. This study was performed to examine whether selective inhibition of renal nitric oxide synthesis affects renin release in vivo. Accordingly, in six barbiturate-anaesthetized dogs renin release was examined before and after intrarenal infusion of the selective inhibitor of(More)
To examine whether an acute increase in plasma potassium concentration ([K]p) may inhibit proximal tubular transport, clearance studies were performed in seven anaesthetized, volume expanded dogs treated with amiloride (1 mg kg-1 body wt) to block tubular potassium secretion, and with bumetanide (30 micrograms kg-1 body wt) to inhibit NaCl reabsorption in(More)
The effects of adding active compression-decompression and abdominal binding separately or combined to standard compression CPR was tested in a randomized cross-over design during ventricular fibrillation in eight pigs. The flow and pressure effects of the two techniques appeared to be additive with no interference between the two. Carotid blood flow(More)
To investigate the effect of endothelin on renin release, experiments were performed in barbiturate-anaesthetized dogs with denervated kidneys. Intrarenal infusion of endothelin (1 ng min-1 kg-1 body wt) reduced renal blood flow (RBF) from 145 +/- 10 ml min-1 to 98 +/- 9 ml min-1 without altering renin release (1 +/- 1 microgram angiotensin I (AI) min-1).(More)
OBJECTIVE Endothelin is increased in plasma following myocardial infarction. Whether brief periods of myocardial ischaemia not leading to myocardial infarction increase plasma endothelin is not known. Thus, the present study was designed to examine cardiac endothelin balance in association with a 10 min coronary artery occlusion followed by reperfusion. (More)
In barbiturate-anesthetized dogs, the effects of intrarenal infusion of the two selective inhibitors of nitric oxide synthesis, NG-monomethyl-L-arginine (L-NMMA) and NG-nitro-L-arginine (NO-Arg), were compared. Basal renal blood flow (RBF) was reduced by 15 +/- 2% after L-NMMA at 0.28 mumol/ml, by 20 +/- 3% after NO-Arg at 0.07 mumol/ml, and by 31 +/- 5%(More)