H. A. Bruining

Correlations of serum potassium fluctuations with body temperature after major surgery

We have observed an association between hypothermia and hypokalemia in a number of postoperative patients. In order to analyze the incidence and consequences of this correlation, 108 patients undergoing major operations were prospectively studied. Rectal temperature, serum and urinary potassium, arterial blood gases, blood glucose, and routine monitoring were analyzed. Hypothermia occurred in 35 (32%) patients, of whom 20 (57%) suffered from hypokalemia. Hypothermia was accompanied by an undercompensated metabolic acidosis in 15 (75%) and hyperglycemia in 18 (89%), while nine (45%) patients had cardiac dysrhythmias. Urinary potassium excretion was lower in hypothermic patients and therefore cannot explain the finding of hypokalemia.Administration of NaHCO3, insulin, digitalis, and calcium in patients suffering from hypothermia must be done with caution because hypokalemia may coexist with low body temperature and predispose the patients to lethal dysrhythmias.

Design and validation of an automatic metabolic monitor

A self-calibrating fully automatic instrument for the measurement of oxygen consumption, carbon dioxide production and the respiratory quotient of mechanically ventilated patients has been developed. The instrument is based on commercially available conventional oxygen and carbon dioxide gas analysers and a domestic natural gas volumetric flow meter. The distribution of the different gas flows, i.e. calibration gases, the inspiratory mixture sample and the expiratory mixture sample, are controlled by in inexpensive microprocessor, which also performs the necessary calculations. The accuracy of the instrument has been validated by bench tests. The present prototype has been in use for over 3000 h without major failures.

Design and validation of an indicator gas injector for multiple gas washout tests in mechanically ventilated patients.

A device to produce a stepwise indicator gas fraction variation to initiate a washout test in mechanically ventilated patients is described. The device, which can be used in conjunction with the commonly used Siemens-Elema series 900 ventilators, is based on simple, off-the-shelf technology. It features the simultaneous use of two indicator gases (so that the influence of diffusion processes in the gas exchange to the patient can be measured) and maintains a nearly constant FIO2 during a washout procedure. With this indicator gas injector, the transition time of the indicator gas fraction at the beginning of a washout proved to be short enough to detect ventilation inhomogeneity by visual inspection of the washout curves. Functional residual capacity measurements using this device are presented on a test lung with known volume, on healthy volunteers, and on critically ill patients. (Crit Care Med 1990; 18:754)

Outcome prediction in critically ill patients by means of oxygen consumption index and simplified acute physiology score

AbstractBoth oxygen consumption index (

Total parenteral nutrition in critically ill surgical patients: fixed vs tailored caloric replacement

\dot V_{O_2 }

Effect of propranolol on surgical bleeding and hemostasis: An in vivo study in the rat

) and simplified acute physiology score (SAPS) are reported to be reliable predictors of the ultimate out-come in critically ill patients. The purpose of this study was to verify whether survivors and nonsurvivors have different

Oxygen Delivery and Oxygen Uptake in Postoperative and Septic Patients

\dot V_{O_2 }