A newly designed flexible fiberoptic bronchoscope for use in intensive care units

A newly designed flexible fibroptic bronchoscope has been manufactured for use in intensive care units (ICU). It has an inside channel of large caliber, diameter 2.5 mm, through which pulmonary secretions can be aspirated directly via the suction tube. Furthermore, prompt bedside use is possible since handle type batteries can easily be attached to the bronchofibroscope. This new instrument is now employed in our ICU for: 1. The diagnosis and treatment of atelectasis. 2. Suction of retained secretions. 3. Detection of tracheal obstruction. 4. Evaluation of endotracheal and tracheostomy tubes whilst in position. 5. Observation of tracheal and bronchial changes. 6. Help in endotracheal intubation. It was used most frequently for the diagnosis and treatment of atelectasis and suction of retained secretions.

Effects of dibutyryl cyclic-AMP on cardiac output and myocardial contractility in dogs

Dibutyryl cyclic-AMP was administered to a group of anesthetized dogs at the doses of 5, 10, 20 and 40 mg/kg, and changes in stroke volume, cardiac output and myocardial contractility were observed. Also, effects of this substance on contractile performance of isolated cardiac muscle were investigated in another group of dogs. Results were as follows: 1) Dibutyryl cyclic-AMP increased heart rate, stroke volume and cardiac output in a dose-related manner in the range from 5 to 40 mg/kg. 2) As indices of myocardial contractility, Vmax and maximum dF/dt were examined. These also showed a dose-dependent increase in response to dibutyryl cyclic-AMP. In isolated dog hearts, dibutyryl cyclic-AMP raised the maximum velocity of shortening (V'max) dose-dependently. 3) Total peripheral resistance declined in a dose-related way. On the other hand, mean arterial pressure and CVP dropped slightly without showing dose-dependence. These results show that dibutyryl cyclic-AMP produces positive inotropic and chronotropic effects and cause dilatation of the peripheral vessels in dose-dependent manners.

Responses to exogenous dibutyryl adenosine 3',5'-monophosphate of cardiac output and blood flow in the renal, superior mesenteric and carotid arteries in anesthetized dogs

Changes in the cardiac output and blood flow in the renal, superior mesenteric and carotid arteries in anesthetized dogs were observed, using the non-cannulating electromagnetic flow meter. Dibutyryl cyclic-AMP, 5 mg/kg body weight, was given intravenously and the following results were obtained: 1) Dibutyryl cyclic-AMP increased the stroke volume and the cardiac output, and slightly increased the heart rate. These effects appeared 3 to 5 min after administration of dibutyryl cyclic-AMP. 2) The mean systemic blood pressure as well as the central venous pressure fell slightly. 3) The renal and the superior mesenteric artery blood flow increased markedly, but the carotid artery blood flow did not change. 4) Distribution of the cardiac output to the renal and superior mesenteric arteries did not change but distribution to the carotid artery decreased. 5) Total peripheral resistance, renal artery vascular resistance and superior mesenteric artery vascular resistance decreased, and carotid artery vascular resistance decreased slightly. 6) The cardiac output and blood flow were enhanced by aminophylline (3 mg/kg), and were not blocked by propranolol (0.3 mg/kg).