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Summary Sepsis continues to be a major unresolved medical challenge of the present. Despite earlier diagnosis and treatment initiation, source control, improvements in the standard of care and attempts at standardization of treatment and resuscitation protocols intensive care unit mortality rates for severe sepsis is 32.2% and 54.1% for septic shock. Further reduction in mortality may be achievable through knowledge and use of the expanding field of adjunctive therapy: a supplement to optimal, supportive, intensive therapy and antibiotic treatment. Numerous and unsuccessful trials targeted at inhibiting various essential inflammatory mediators and receptors involved in the sepsis syndrome have failed to show a reduction in mortality, raising the question whether mortality in sepsis actually derives from an uncontrolled pro-inflammatory response. Thus, more broad based attempts at modulating the inflammatory response to infection like corticosteroids and drotrecogin alfa (activated) are to date the only drugs to have demonstrated mortality benefits in large randomized controlled trials. Advances in understanding the pathophysiology of sepsis as a heterogeneous, dynamic syndrome caused by imbalances in the inflammatory network have provided newer hemofiltration techniques with a strong treatment rationale. Furthermore, endotoxin adsorption, if effective, has the potential to prevent further progression of the biological cascade of gram-negative sepsis.

Background Gut ischaemia may contribute to morbidity in sepsis, but little is known about the metabolic state of the gut mucosa in such patients. Methods Nine patients with abdominal septic shock treated with norepinephrine, and ten healthy subjects, were subjected to equilibrium dialysis with a rectal balloon. pH, P co 2 and concentrations of l -lactate were measured by auto-analyser. Results In rectal dialysis fluid from patients with septic shock, acidosis was present (pH 7.23, 95% CI 7.11–7.36) and concentrations of l -lactate were approximately five times greater than controls (2.5–5.8 vs 0.5–1.2 mmol litre−1). The lactate concentration was related to the dose of norepinephrine (P co 2 did not differ significantly between patients and controls (6.4–11.0 vs 8.9–13.8 kPa). Conclusions The results suggest that, either lactic acidosis in rectal mucosa is related to shock severity, or that norepinephrine causes mucosal ischaemia. In any case, metabolic dysfunction is present in the rectal mucosa in patients with abdominal septic shock treated with norepinephrine.

The need for revision total hip arthroplasty has been increasing. The early results have been poor, and different revision techniques have been introduced. We report our results of 84 consecutive cemented first-time revisions of femoral components performed from 1981 through 1988 using a long-stem revision component. The average time to follow-up was 11.4 years (range, 7.9–15.0 years). Patients with 47 revisions had died; 2 of these had been rerevised. Two additional patients were lost to follow-up for other reasons. Of the living patients, 12 had been rerevised, leaving 23 patients (23 hips) for complete follow-up evaluation, including clinical and radiographic assessment. Of 23 patients, 15 reported no pain, 4 had only slight pain, and 4 had more severe pain. In 4 cases, there were definite radiographic signs of loosening of the femoral component. Kaplan-Meier survivorship analysis showed an overall 10-year survival of the femoral component of 77.9%. Using rerevision because of aseptic loosening or definite radiographic loosening as endpoint, the 10-year survival was 80.7%. Simple recementation is well indicated in elderly patients with only minor bone loss.

The development of the leak telescope as a tool for detecting minute leaks inside a vacuum chamber is described. A more detailed model for the leak telescope that takes into account a variety of real-life effects has been developed. The model was experimentally verified and refined. Experimental results demonstrated that a fairly primitive leak telescope can detect the position of relatively small leaks (i.e. 1*10/sup -5/ torr-l/s) at large distances (i.e. 1 m) in high vacuum (i.e. 1*10/sup -7/ torr). The concept of an oscillating leak telescope holds promise for even better performance. >

The motions of the DIII-D vacuum vessel during vertical instabilities of elongated plasmas have been measured and studied over the past five years. The currents flowing in the vessel wall and the plasma scrapeoff layer were also measured and correlated to a physics model. These results provide a time history load distribution on the vessel which was input to a dynamic analysis for correlation to the measured motions. The structural model of the vessel using the loads developed from the measured vessel currents showed that the calculated displacement history correlated well with the measured values. The dynamic analysis provides a good estimate of the stresses and the maximum allowable deflection of the vessel. In addition, the vessel motions produce acoustic emissions at 21 Hz that are sufficiently loud to be felt as well as heard by the DIII-D operators. Time history measurements of the sounds were correlated to the vessel displacements. An analytical model of an oscillating sphere provided a reasonable correlation to the amplitude of the measured sounds. >

Experimentally measured growth rates of the positional instability of vertically elongated plasmas in Doublet III are compared with those obtained from a numerical code based on linear perturbation theory. The relevant elements of the circumstances of the experiment have been included in the code. The perturbations of plasma currents and currents in the wall of the vacuum vessel as well as in the coils surrounding the plasma are included in the model. The modelling of the complicated external circuitry of the coils is based on a simple assumption which was supported by observation. Comparison of the measured growth rates with those calculated suggests that the essential phenomena are adequately described by the model.