Acta anaesthesiologica Scandinavica
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Acta Anaesthesiol Scand · May 2000
Randomized Controlled Trial Clinical TrialThe effect of dopexamine on regional tissue oxygenation, systemic inflammation and amino acid exchange in major abdominal surgery.
Beta-adrenergic agents are frequently used to improve cardiac performance in surgical and intensive care patients. Beta-adrenergic agents have metabolic and anti-inflammatory effects in addition to their cardiovascular effects. Splanchnic metabolic activity increases in response to surgery and inflammation. Dopexamine is believed to favor blood flow distribution to the splanchnic region. ⋯ Dopexamine, when added to a preoperative stabilization protocol with fluids, did not augment the postoperative hemodynamic response, and had no effect on postoperative metabolic and inflammatory responses.
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Acta Anaesthesiol Scand · May 2000
Evaluation of pressure/volume loops based on intratracheal pressure measurements during dynamic conditions.
The aim of this study was to evaluate and compare information about lung mechanics obtained by dynamic pressure/volume loops based on Y-piece and intratracheal airway pressure. ⋯ By measuring airway pressure at the trachea the effect of endotracheal tube resistance during inspiration is excluded while it is included during expiration, yielding correct end-points of inspiration and expiration. This makes it possible to calculate accurately total compliance of the respiratory system during dynamic conditions. By monitoring of airway pressure in the trachea, respiratory mechanics can be assessed more accurately and ventilatory settings adjusted to attenuate ventilator induced lung injury.
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Acta Anaesthesiol Scand · May 2000
Pulsatility does not change cerebral oxygenation during cardiopulmonary bypass.
To determine the effect of pulsatility during cardiopulmonary bypass (CPB) on cerebral oxygenation, we measured oxyhaemoglobin (HbO2), deoxyhaemoglobin (Hb) and oxidised cytochrome aa3 (CtO2) with near-infrared spectroscopy (NIRS) in 14 patients electively scheduled for cardiac surgery. ⋯ Neither oxygenated haemoglobin, nor intracellular oxygenation, represented by CtO2, indicated a beneficial effect of pulsatile perfusion during hypothermic CPB. These results, however, are only valid for short time effects within 10 min before rewarming from CPB and patients without flow-limiting stenoses of the carotid artery.
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Acta Anaesthesiol Scand · May 2000
Case ReportsTwo instances of central nervous system toxicity in the same patient following repeated ropivacaine-induced brachial plexus block.
We describe two instances of central nervous system (CNS) toxicity in the same patient following repeated brachial plexus blocks induced by high doses of ropivacaine (6 mg x kg(-1) and 4.5 mg x kg(-1), respectively). Although very high total and free plasma concentrations of ropivacaine were found up to 98 min after induction of the blocks, no signs of cardiovascular toxicity apart from hypertension and sinus tachycardia were observed. ⋯ These high doses, however, resulted in severe toxic CNS symptoms. Therefore, it is stressed that the dose in relation to the weight of the patient must be calculated when administering a large volume of local anesthetic.
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Acta Anaesthesiol Scand · May 2000
A new method for non-invasive, manoeuvre-free determination of "static" pressure-volume curves during dynamic/therapeutic mechanical ventilation.
Lung mechanics are usually measured using static or quasistatic methods, abandoning normal ventilatory treatment. We have developed a method to calculate the alveolar pressure during dynamic/therapeutic conditions, "the dynostatic pressure" (P(dyn)), using airway pressure (P) measured in the trachea and volume (V) and flow (V) at the Y-piece. ⋯ The dynostatic method gives a breath-by-breath reflection of the interaction between ventilatory settings and lung mechanics in patients during ordinary ventilator treatment. It is only marginally affected by the moderate differences in inspiratory versus expiratory resistances present in patients with ALI.