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General anaesthesia has been the most commonly used method for almost all types of thoracic surgery. Recently, there has been a growing interest in non-intubated anaesthetic techniques. The rationale being, to prevent complications related to general anaesthesia and positive pressure ventilation such as barotrauma or ventilation-perfusion mismatch. We present a case with severely impaired forced expiration volume (26%), carbon monoxide diffusing capacity (26%) and VO2max (13.9 mL/kg/min). According to current guidelines, this patient was suitable to undergo one-lung ventilation only with high risk of morbidity and mortality. Therefore, we chose the non-intubated technique for thoracotomy. Oxygenation was satisfactory throughout, the patient remained hemodynamically stable and the operation was uneventful. Oxygen supplementation was stopped from day 2 and he was discharged on day 7. To our knowledge, this is the first case report where a planned non-intubated method was applied for thoracotomy, and our results suggest that it might be a feasible and safe approach for open thoracotomy in difficult cases where severely impaired lung function indicates that one lung ventilation may carry significant risks.

The current protocol is a bleeding-resuscitation model intended to imitate the effects of severe blood loss and subsequent fluid resuscitation. The experimental subjects were Vietnamese pot-bellied pigs of both sexes weighing 33±4 kg. The animals underwent a 12-hours fasting pre-operatively but had free access to water. Anesthesia was induced by intramuscular injection of a mixture of ketamine (20 mg/kg) and xylazine (2 mg/kg) and maintained with a continuous iv. infusion of Propofol (50 µL/min/kg IV; 6 mg/kg/hr), while analgesia was maintained with intermittent nalbuphine (0.1 mg/kg). After endotracheal intubation, the animals were mechanically ventilated with a Hamilton C1 respirator (Hamilton Medical AG, USA). The tidal volume was set to 10 ml/kg, and the respiratory rate was adjusted to maintain the end-tidal carbon dioxide and partial pressure of arterial carbon dioxide within the range of 35–45 mmHg and the arterial pH between 7.35 and 7.45. The depth of anaesthesia was assessed by checking jaw tone. After induction of anaesthesia, catheters were inserted into the left jugular vein, left external carotid artery and the left femoral artery. For invasive hemodynamic monitoring, a transpulmonary thermodilution catheter (PiCCO, PULSION Medical Systems SE, Munich, Germany) was used. The femoral artery served as the site for arterial blood gas sampling, the central venous line was used for taking central venous blood gas samples and for the injection of cold saline boluses for the thermodilution measurements, whilst the carotid arterial catheter was used for draining blood. A transpubic catheter was placed into the urinary bladder for monitoring renal function. Animals were covered in scrubs and an external heating device was used to maintain physiological body temperature.

INTRODUCTION Fluid resuscitation is the cornerstone of treatment in hemorrhagic shock. Despite increasing doubts, several guidelines recommend to maintain mean arterial pressure (MAP) >65 mmHg as the most frequent indication of fluid therapy. Our aim was to investigate the effects of a MAP-guided management in a bleeding-resuscitation animal experiment. MATERIALS AND METHODS After anesthesia and instrumentation (tbsl) animals were bled till the initial stroke volume index dropped by 50% (t0). Fluid replacement was performed in 4 equivalent steps (t1-4) with balanced crystalloid solution to reach the baseline values of MAP. Invasive hemodynamic measurements and blood gas analyses were performed after each step. RESULTS Mean arterial pressure dropped from tbsl to t0 (114±11 vs 76.9±16.9 mmHg, p

Acrylic polymers in aqueous dispersions are very often used to prepare coating suspensions which contain insoluble particles. The mixing of the pigment suspension and the polymer dispersion is a very important step in the preparation of the liquid. The stirring can cause precipitation of the polymer and foam formation. Foam formation from different Eudragit dispersions was evaluated in this study. A high-speed mixer was applied and the foam and liquid phases formed were separated. The changes in concentration of the polymer in the two phases were studied by FT-IR with a horizontal attenuated total reflection (HATR) accessory. The presence of shape-holding foam can be detected at very different rates of stirring. The most intensive foam formation was detected for Eudragit FS 30 D. The Eudragit RL 30 D dispersion was the least sensitive to high-speed mixing. The relative content of the polymer in the foam was higher than that in the liquid. This is indicated by the accumulation of surface-active agent on the surface of the bubbles formed in the foam. This phenomenon differed considerably for the various dispersions. An exact knowledge of the foam formation from aqueous acrylic dispersions is very important in order to determine the parameters of mixing and the quantity of antifoaming agent.

The permeable polymer film-formation behavior of a Eudragit RS dispersion was investigated in response to stirring at various rates and for various times in an Ultra Turrax instrument. No additives were used. The minimum film-forming temperature of the liquid, the thermal behavior of the film and the compositions of the dispersion and the foam arising were investigated. It was found that, at a given mixing time, shape-retaining foam formation could be detected at over 17,500 rpm. The polymer was enriched in the foam, while its quantity was decreased in the liquid. The minimum film-forming temperature of the liquid phase did not vary significantly, with the exception of the rate of 24,000 rpm, when a uniform film was not formed because of the bubbles. The glass-transition temperatures of the films formed did not exhibit any differences. Film formation was not influenced by the stirring time at a given rate. It was found that the efficiency of homogenization should not be increased by using a high stirring rate, as a uniform, smooth film did not develop, such a film being indispensable to ensure appropriate drug release. Copyright © 2006 John Wiley & Sons, Ltd.