In this model of lung injury induced solely by mechanical forces, the prone position resulted in a less severe and more homogeneous distribution of ventilator-induced lung injury. These results parallel those previously obtained in oleic acid-preinjured animals ventilated with higher positive end-expiratory pressure.
We conclude that the ventilatory strategy most likely to overdistend the lungs while allowing repetitive opening and closure of alveoli (group 2) facilitated bacterial translocation from the alveoli to the bloodstream and increased lung injury, as determined by histologic and gravimetric analysis. PEEP ameliorated these effects, despite lung overdistention, but increased histologic and gravimetric indices of lung injury in dependent as compared with the nondependent regions.
After oleic acid-induced lung injury, animals ventilated with high tidal volume and PEEP undergo less extensive histologic change in the prone position than in the supine position. The prone position alters the distribution of histologic abnormalities.
Sequential blood and bone marrow specimens from 53 patients receiving recombinant granulocyte (G-CSF) or granulocyte macrophage colony stimulating growth factor (GM-CSF) for neutropenia were evaluated. The blood findings were marked by a neutrophilia with a prominent left shift, increased azurophilic granulation, Döhle bodies, and an elevated leukocyte alkaline phosphatase; circulating myeloblasts were observed but did not exceed 2% of the leukocytes. Nuclear segmentation abnormalities consisting of hyposegmentation, hypersegmentation, and ring nuclei were noted but were not a prominent finding. A leukoerythroblastosis was present in 54% of patients. No consistent effect on cell lines other than neutrophils was found. A monocytosis was present in 12 patients, a transient lymphocytosis in 2 and an eosinophilia in 1. No effect was evident on basophils. The morphologic changes in the neutrophils in the bone marrow specimens were most pronounced in the early period of growth factor therapy with a relative neutrophil hyperplasia with a marked increase in promyelocytes and myelocytes. With increasing duration of therapy, the myeloid to erythroid ratio normalized and the percentage of promyelocytes decreased while myelocytes and band neutrophils increased. Thirteen patients had no response to growth factor. The nonresponding patients were clinically diverse; all bone marrow biopsy specimens in this group were virtually acellular. No differences were noted between G-CSF and GM-CSF.
A markedly elevated prothrombin time (PT) and activated partial thromboplastin time (APTT) were observed in a 24-year-old man who was admitted with a history of ethylene glycol ingestion. Further laboratory evaluation suggested that the coagulopathy was related to acquired factor deficiencies. The PT and APTT improved transiently on usual doses of vitamin K, but rapidly became abnormal again. The coagulopathy was controlled only after large doses of vitamin K for at least 37 days. On further questioning, the patient admitted to consuming a large quantity of a rodenticide. The second generation anticoagulant rodenticides (superwarfarins) result in a potent and prolonged anticoagulant effect by reducing the activity of the vitamin K dependent factors (II, XII, IX, and X). To our knowledge, this is the first reported concomitant ingestion of both ethylene glycol and a superwarfarin compound. This case serves to illustrate how a logical laboratory evaluation can lead to the proper diagnosis, despite a misleading clinical history.
Warfarin therapy has traditionally been monitored using the prothrombin time (PT). A significant problem with this assay is the variable sensitivity of commercially available thromboplastin reagents to reduction of vitamin K-dependent coagulation factors. The International Normalized Ratio (INR) was developed as a means of standardizing PT values between laboratories that use different thromboplastins and types of instrumentation. Parallel testing of samples from 63 patients stabilized on oral anticoagulation with five different thromboplastins was undertaken. Forty-eight percent of all samples had INR values that were not identical but showed good correlation. Fifty-two percent of the samples had clinically significant discrepancies of their INR values. In this group, patients in the therapeutic range with one thromboplastin appeared over- or underanticoagulated based on the INR using a different thromboplastin. In order to determine whether use of a low-ISI thromboplastin reagent could provide more reproducible INR results, concurrent testing of specimens from 36 patients on stable oral anticoagulation was undertaken between our hospital laboratory and another, nonaffiliated institution. Both hospitals used similar instrumentation and thromboplastin reagents. Under these conditions, the INR values generated between laboratories correlated highly. The inability to generate consistent INR values in parallel testing using different thromboplastins with identical samples and instrumentation raises concern about the reliability of the INR, and suggests that further analysis is necessary to identify the source of these discrepancies. In the interim, our data show use of a recombinant thromboplastin with a low-ISI value substantially improves interlaboratory variation in INR value. Key Words: International Normalized Ratio—Prothrombin time—Thromboplastin—Anticoagulation monitoring.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.