D-dimer correlates with proinflammatory cytokine levels and outcomes in critically ill patients.

STUDY OBJECTIVES: To determine the relationship between d-dimer (DD) and both proinflammatory and anti-inflammatory cytokine levels, and to confirm the association between DD status and outcomes in critically ill patients. DESIGN: Prospective observational study. SETTING: Medical ICU (MICU) of a tertiary care, academic medical center. PATIENTS: Individuals admitted to the MICU. INTERVENTIONS: Within 24 h of MICU admission, patients had DD status determined and interleukin (IL) levels (IL-6, IL-8, and IL-10) and tumor necrosis factor (TNF)-alpha measured. The strength of the DD level was also noted. Subjects were then monitored prospectively to determine mortality rate and the incidence of organ failure. MEASUREMENT AND RESULTS: The study cohort included 79 patients (mean age, 65.2 years; 54.5% male patients). DD was present in 53.2% of subjects. The DD reaction was weak (1+) in 15 patients and strong (2+) in 27 patients. The TNF-alpha, IL-6, and IL-8 levels all increased in parallel with the increasing strength of the DD level. IL-10 levels did not differ based on DD status. Similarly, the severity of illness as measured by the APACHE (acute physiology and chronic health evaluation) II score was highest among those with higher DD levels: 24.7 +/- 6.2 for those with 2+ DD vs 17.2 +/- 3.1 and 11.5 +/- 2.7 for those with 1+ DD and no circulating DD, respectively (p < 0.001). For patients lacking DD, the mortality rate was 8.1%, compared to 13.3% and 55.6% for those with 1+ and 2+ DD levels, respectively (p < 0.001). No patient without DD had multisystem organ failure (MSOF) develop, while the incidence of MSOF also increased with increasing DD levels. As a screening test for mortality, the DD performed as well as the APACHE II system. CONCLUSIONS: The coagulation system is active in critically ill patients, and DD levels correlate with activation of the proinflammatory cytokine cascade. The absence of a relationship between DD and anti-inflammatory cytokines (IL-10) suggests that the presence of DD may reflect the imbalance between proinflammatory and anti-inflammatory cytokines. DD identifies patients at increased risk for both MSOF and death.

Effect of driving pressure and nebulizer model on aerosol output during intermittent delivery with a dosimeter.

Recent guidelines reinforce the need for a standardized technique during inhalational bronchoprovocation challenge testing. We investigated the effects of nebulizer model and dosimeter driving pressure on nebulizer output using a nebulized saline model. Four nebulizers (Hudson 1720, Salter 8900, Baxter Airlife, and DeVilbiss 644) were evaluated at two driving pressures (20 and 50 pounds per square inch [psi]) via a dosimeter (Salter 700) that delivered a 0.6-sec actuation. Output was determined gravimetrically after 20 actuations of saline at constant respiratory flow and volume. Output per actuation at 20 psi was 2.83 +/- 0.41 mg (mean +/- SD), 4.58 +/- 0.66, 4.75 +/- 0.42, and 4.75 +/- 1.37 for the Hudson, Salter, Baxter, and DeVilbiss, respectively, and 6.75 +/- 0.61 mg, 9.17 +/- 0.88, 9.42 +/- 1.32, and 9.83 +/- 1.75 at 50 psi. The Hudson delivered a lower volume than the other nebulizers (p < 0.0005). At 20 psi, output from the DeVilbiss had greater variability (coefficient of variation = 28.8%) compared to the Baxter (CV = 8.8%; p = 0.045). The output was greater at 50 psi than 20 psi for all models (p < 0.0005). These results demonstrate that, when choosing a nebulizer driven by a dosimeter, it is important to base that selection on published data describing aerosol output under different driving pressures.

Long-distance air evacuation of blast-injured sailors from the U.S.S. Cole.

BACKGROUND: The U.S. military uses a Critical Care Air Transport Team (CCATT) to air evacuate critically ill patients to facilities that can provide definitive medical care. CCATT is comprised of highly trained personnel and each team uses specialized equipment to allow for in-flight intensive medical care of patients. CCATT has the capability of providing care over long duration and distance. This report describes our recent experience of long-distance fixed-wing medical air evacuation of multiple critically ill sailors with blast injuries from the U.S.S. Cole. CONCLUSION: CCATTs can safely transport multiple critical patients with blast injuries over long distance and duration by fixed-wing aircraft. Blast injuries can have multi-system effects and patients with subclinical pulmonary injury may be asymptomatic when hypoxemic in a hypobaric environment.