UNLABELLED The mechanism of tourniquet-induced arterial pressure increase is not known. We investigated the effect of preoperative ketamine on tourniquet-induced arterial pressure and heart rate changes in 85 patients undergoing knee surgery with a tourniquet under general anesthesia. Patients were randomly assigned into three groups; Large Ketamine (n = 28; ketamine 1.0 mg/kg), Small Ketamine ...

emergence from general anesthesia can be associated with coughing, agitation, and hemodynamic disturbances. remifentanil may attenuate these responses. we have examined the effect of remifentanil on the hemodynamic response to the emergence from anesthesia and tracheal extubation. in a double-blind, randomized trial, we enrolled 50 adult patients undergoing abdominal surgery. all patients recei...

The possibility that venous blood could be withdrawn through a radial artery cannula when venous pressure is high was examined in 30 patients during cardiopulmonary bypass for coronary artery bypass operation. Progressive desaturation of radial artery blood occurred when venous pressure was equal to arterial pressure. Desaturation not only increased with duration of venous obstruction but also ...

IT IS WELL recognized that patients with sickle-cell disease may have a low saturation and tension of arterial blood oxygen. Although arterial anioxemia was first observed in 1942, its exact mechanism is still unknown.1 It has been shown that the hemoglobin dissociation curve of these patients is shifted to the right, probably because of a decrease in erythrocyte pH.2, 3 Therefore, a norimal le...

The severity of pulmonary hypertension was evaluated by right cardiac catheterization in 89 patients with stable chronic obstructive pulmonary disease, both at rest and during maximum treadmill exercise. Thirty-one patients were found to have pulmonary hypertension at rest, defined as a mean pulmonary arterial pressure of 20 mm Hg or more. Although the remaining 58 patients had normal mean pulm...

A 3-month-old infant of 33 weeks' gestation was hospitalized with pneumonia caused by Bordetella pertussis. Respiratory insufficiency worsened, and on hospital day 3, there was severe pulmonary dysfunction (arterial oxygen pressure/fraction of inspired oxygen ratio: 120), extreme leukocytosis (white blood cell count 104,000/mm3), and severe pulmonary hypertension as assessed by 2-dimensional ec...

OBJECTIVES Neurological impairment occurs in up to 25% of infants undergoing cardiopulmonary bypass with or without circulatory arrest. Potential causes include alterations in cerebral blood flow, hypoxia and embolisation. During cardiopulmonary bypass, arterial oxygen tension is maintained at levels which under normal conditions cause cerebral vasoconstriction; this is a potential mechanism fo...

We build an evolutionary scenario that explains the selection of core physiological quantities of the arterial network of mammals. We propose that the arterial network evolved under the constraint of its function as an organ. To support this hypothesis, we focus on one of the main function of blood network: oxygen supply to the organs. We consider an idealized organ with a given oxygen need and...

BACKGROUND AND PURPOSE Oxygen supplementation is the treatment most commonly used to relieve dyspnea in chronic obstructive pulmonary disease (COPD). There is a lack of data, however, on the response of the respiratory drive to low flow oxygen in severe stable COPD. The purpose of this investigation was to evaluate the magnitude of chemoresponsiveness to low flow supplemental oxygen in patients...