Measurement of left mainstem bronchus using multiplane CT reconstructions and relationship between patient characteristics or tracheal diameters and left bronchial diameters.

STUDY OBJECTIVES: To measure the tracheal diameters (TDs) [transverse (Tr) TD, and anteroposterior (AP) TD] and left main bronchus diameters (LBDs) [Tr and AP] using multiplane CT scan reconstructions with a tridimensional correction of the declination. To evaluate the relationship between clinical variables and CT scan diameters of the tracheobronchial tree. To aid in the selection of a double-lumen tube of appropriate size. DESIGN: Prospective observational study. SETTING: Private and university hospitals. PATIENTS: A total of 206 patients (105 women and 101 men) undergoing a CT scan for medical investigations or preoperative evaluation. INTERVENTION: No intervention. MEASUREMENTS AND RESULTS: TDs and LBDs are greater in men (p < 0.001). The Tr-TD is smaller than AP-TD for men (p < 0.001). The Tr-LBD is greater than AP-LBD in both sexes (p < 0.001). In men, height, Tr-TD, and AP-TD are predictive factors for Tr-LBD, while Tr-TD and AP-TD are the only predictive factors for AP-LBD. In women, Tr-TD and AP-TD are the only predictive factors for Tr-LBD and AP-LBD. The smallest LBD (ie, the lesser of the Tr-LBD or the AP-LBD [called the smallest LBD]) is the Tr-LBD in 25.2% of the cases. The mean (+/- SD) ratio of the smallest LBD/Tr-TD is 0.70 +/- 0.14 for men and 0.65 +/- 0.12 for women. The estimated (Est) LBD is calculated using this ratio. The mean value for Est-LBD minus the smallest LBD is 1.6 +/- 1.3 mm, and this difference is < 1 mm in 40% of male patients and 39% of female patients. CONCLUSIONS: In conclusion, the left main bronchus is most often elliptic, and the smallest LBD cannot be accurately evaluated using patient characteristics or a ratio from TD.

High levels of catalytic antibodies correlate with favorable outcome in sepsis.

Sepsis is the leading cause of death in intensive care units and results from a deleterious systemic host response to infection. Although initially perceived as potentially deleterious, catalytic antibodies have been proposed to participate in removal of metabolic wastes and protection against infection. Here we show that the presence in plasma of IgG endowed with serine protease-like hydrolytic activity strongly correlates with survival from sepsis. Variances of catalytic rates of IgG were greater in the case of patients with severe sepsis than healthy donors (P < 0.001), indicating that sepsis is associated with alterations in plasma levels of hydrolytic IgG. The catalytic rates of IgG from patients who survived were significantly greater than those of IgG from deceased patients (P < 0.05). The cumulative rate of survival was higher among patients exhibiting high rates of IgG-mediated hydrolysis as compared with patients with low hydrolytic rates (P < 0.05). An inverse correlation was also observed between the markers of severity of disseminated intravascular coagulation and rates of hydrolysis of patients' IgG. Furthermore, IgG from three surviving patients hydrolyzed factor VIII, one of which also hydrolyzed factor IX, suggesting that, in some patients, catalytic IgG may participate in the control of disseminated microvascular thrombosis. Our observations provide the first evidence that hydrolytic antibodies might play a role in recovery from a disease.