ROC trials update on prehospital hypertonic saline resuscitation in the aftermath of the US-Canadian trials

The objectives of this review are to assess the current state of hypertonic saline as a prehospital resuscitation fluid in hypotensive trauma patients, particularly after the 3 major Resuscitation Outcomes Consortium trauma trials in the US and Canada were halted due to futility. Hemorrhage and traumatic brain injury are the leading causes of death in both military and civilian populations. Prehospital fluid resuscitation remains controversial in civilian trauma, but small-volume resuscitation with hypertonic fluids is of utility in military scenarios with prolonged or delayed evacuation times. A large body of pre-clinical and clinical literature has accumulated over the past 30 years on the hemodynamic and, most recently, the anti-inflammatory properties of hypertonic saline, alone or with dextran-70. This review assesses the current state of hypertonic fluid resuscitation in the aftermath of the failed Resuscitation Outcomes Consortium trials.

Effects of three different types of exercise on blood leukocyte count during and following exercise

CONTEXT: High-intensity exercise causes tissue damage, production of stress hormones, and alterations in the function and quantity of various immune cells. Many clinical-physical stressors such as surgery, trauma, burns and sepsis induce a pattern of hormonal and immunological response similar to that of exercise. It has thus been suggested that heavy exercise might be used to cause graded and well-defined amounts of muscle trauma, thereby serving as an experimental model for inflammation and sepsis. OBJECTIVE: In order to explore whether some form of strenuous exercise might provide an useful model for the inflammatory process, we studied the effects of three different exercise protocols on blood leukocyte count during and following exercise. DESIGN: Four different experimental conditions, using a randomized-block design. SETTING: Defence and Civil Institute of Environmental Medicine, North York, Ontario, Canada. PARTICIPANTS: Eight healthy and moderately fit males. PROCEDURES: Participants were each assigned to four experimental conditions. Subjects performed 5 minutes of cycle-ergometry exercise at 90 percent, 2 hours of cycle-ergometry exercise at 60 percent, a standard circuit of resistance exercises with 3 sets of 10 repetitions at 60 to 70 percent of one-repetition maximum (1-RM) force at each of 5 different stations; or they remained seated for 5 hours. DIAGNOSTIC TEST USED: Flow cytometric analysis. MAIN MEASUREMENTS: Blood samples were analyzed for total leukocyte counts, total T cells, T helper/inducer cells, T suppressor/cytotoxic cells, B cells, cytolytic T cells, and natural killer cells. RESULTS: The peak aerobic and prolonged submaximal exercise induced similar alterations in cell counts. These changes were generally larger than those produced by the resistance exercise, although both resistance and peak aerobic exercise resulted in a significantly longer-lasting decrease in the CD4+/CD8+ ratio than the submaximal exercise bout did. CONCLUSION: The data suggest that, of the three exercise patterns tested, prolonged aerobic exercise induced the largest and most readily measured patterns of immune response. Nevertheless, the changes provided only a partial model for the clinical inflammatory process