Search

Objectives: Tissue oxygen saturation (StO(2)) assessed using Near Infrared Spectroscopy and its derived parameters during a vascular occlusion test (VOT) can detect microvascular changes in septic shock patients. General anesthesia (GA) impacts microcirculation. Our aim was to study the effects of general anesthesia on StO(2) and StO(2) derived parameters obtained during VOT in patients referred for cardiac surgery.Methods: We studied 15 patients referred for cardiac surgery before and after induction of GA. Before GA induction, we also studied 15 healthy volunteers (non patients) in order to compare baseline physiological data between patients and healthy subjects. Hemodynamic and microcirculatory (StO(2), ischemic slope, reperfusion slope, and hyperemic response) data were recorded at each step. We used the Inspectra StO(2) system (Hutchinson Inc, MN, USA) with a sensor placed on the thenar eminence. StO(2) values were obtained at baseline and during a VOT. A sphyngomanometer was placed on the forearm above the StO(2) probe and the cuff was then rapidly inflated 30 mmHg above systolic pressure and was maintained inflated until the StO(2) value reached 40%. It was then rapidly deflated.Results: Healthy volunteers had significantly higher reperfusion slope than patients (348 [251-393] vs. 261 [185-279] %/min; P < 0.05). GA induction induced no significant change in StO(2) value compared to baseline (79 [75-85] vs. 80 [76-86]%; P = 0.57). We observed a significant decrease in ischemic slope (from -12 [-16--8] to -8 [-10--6] %/min; P = 0.004) and in reperfusion slope (from 261 [185-279] %/min to 164 [151-222] %/min; P = 0.008) suggesting a decrease in local metabolic rate and a negative impact on reperfusion reserve induced by anesthesia.Conclusion: StO(2) derived parameters during a VOT are impacted by GA induction. These parameters may have potential for microcirculation assessment in patients undergoing surgery. [ABSTRACT FROM AUTHOR]

Infection in patients with serious burns is usually linked to care procedures. It occurs beyond the 48th hour and is the leading cause of mortality. The risk of infection is higher in certain elderly patients or those in a precarious situation. Its frequency can be controlled by high quality and well-organised care.

Background: In hemodynamically unstable patients, the management of retroperitoneal vascular trauma is both difficult and challenging. Endovascular techniques have become an alternative to surgery in several trauma centers., Methods: Between 2004 and 2006, 16 patients (nine men, mean age: 46 years, range: 19-79 years) with retroperitoneal vascular trauma and hemodynamic instability were treated using an endovascular approach. The mean injury severity score was 30.7 ± 13.1. Mean systolic blood pressure and the shock index were 74 mm Hg and 1.9, respectively. Vasopressor drugs were required in 68.7% of cases (n = 11). Injuries were attributable to road traffic accidents (n = 15) and falls (n = 1). The hemorrhage sites included the internal iliac artery or its branches (n = 12) with bilateral injury in one case, renal artery (n = 2), abdominal aorta (n = 1), and lumbar artery (n = 1)., Results: In all, 14 coil embolizations and three stent-grafts were implanted. The technical success rate was 75%, as early re-embolization was necessary in one case and three patients died during the perioperative period. Six patients died during the period of hospitalization (37.5%). No surgical conversion or major morbidity was reported., Conclusion: In comparison with particulates, coil ± stent-graft may provide similar efficacy with regard to survival, and thus may be a valuable solution when particulate embolization is not available or feasible., (Copyright © 2011 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)

Background: Growing evidence suggests that the microvascular dysfunction is the key element of the pathogenesis of septic shock. This study's purpose was to explore whether the outcome of septic shock patients after early resuscitation using early goal-directed therapy is related to their muscle tissue oxygenation., Methods: Tissue oxygen saturation (Sto2) was monitored in septic shock patients using a tissue spectrometer (InSpectra Model 325; Hutchinson Technology, Hutchinson, MN). For the purpose of this retrospective study, the Sto2 values were collected at the first measurement done after the macrohemodynamic variables (mean arterial pressure, urine output, central venous saturation in oxygen) were optimized., Results: After the hemodynamic variables were corrected, no difference was observed between the nonsurvivors and survivors, with the exception of pulse oximetry saturation (94% [92-97%] vs. 97% [94-99%], P = 0.04). The Sto2 values were significantly lower in the nonsurvivors than in the survivors (73% [68-82%] vs. 84% [81-90%], P = 0.02). No correlations were found between the Sto2 and Spo2 (P = 0.7)., Conclusions: In septic shock patients, tissue oxygen saturation below 78% is associated with increased mortality at day 28. Further investigations are required to determine whether the correction of an impaired level of tissue oxygen saturation may improve the outcome of these patients.

Parasites and parasitoids exert an important selection pressure on organisms and, thus, play an important role for both population dynamics and evolutionary responses of host species. We investigated host-parasite interactions in a brood-caring wasp, the European beewolf, Philanthus triangulum (Hymenoptera, Sphecidae), and asked whether females of this species might employ temporal or spatial strategies to reduce the rate of attack by a specialised brood parasitoid, the cuckoo wasp Hedychrum rutilans (Hymenoptera, Chrysididae). Females of the host species might shift their activity to periods of low parasitoid activity both in the course of the season and in the course of the day. On a spatial scale, aggregated or dispersed nesting might be favoured depending on the form of the density dependence of parasitism. The beginning and end of the flight season of host and parasitoid were nearly identical. Activity of chrysidids relative to beewolves did not change significantly during the flight season. However, relative parasitoid activity declined in the course of the day, suggesting the existence of temporal enemy-free space in the evening hours. Shifting the main activity to the evening hours might be a flexible response of beewolves to the presence of chrysidids. Activity of cuckoo wasps per nest was independent of nest density but the actual rate of parasitism as revealed by nest excavations indicated direct density dependence. Total mortality, however, was inversely density dependent. Thus, in the study population aggregated nesting did not reduce parasitism but minimised total mortality.