Search

Presents a study which analyzes the increased plasma viscosity at extreme hemodilution levels in terms of microvascular tone, blood flow, functional capillary density and oxygen distribution to determine the functional state of the microvasculature under these conditions. Materials and methods used on the study; Results and discussion.

Looks at a study which examined the radial pO2 profiles in vivo for the periarteriolar tissue of the rat mesentery, using noninvasive phosphorescence quenching microscopy. Identification of the major function of the blood circulation; Regulation of the blood flow; Methodology used to conduct the study; Results of the study.

The microvascular distribution of oxygen was studied in the arterioles and venules of the awake hamster window chamber preparation to determine the contribution of vascular smooth muscle relaxation to oxygen consumption of the microvascular wall during verapamil-induced vasodilatation. Verapamil HC1 delivered in a 0.1 mg/kg bolus injection followed by a continuous infusion of 0.01 mg·kg-1·min-1 caused significant arteriolar dilatation, increased microvascular flow and functional capillary density, and decreased arteriolar vessel wall transmural Po2 difference. Verapamil caused tissue Po2 to increase from 25.5 ± 4.1 mmHg under control condition to 32.0 ± 3.7 mmHg during verapamil treatment. Total oxygen released by the microcirculation to the tissue remained the same as at baseline. Maintenance of the same level of oxygen release to the tissue, increased tissue Po2, and decreased wall oxygen concentration gradient are compatible if vasodilatation significantly lowers vessel wall oxygen consumption, which in this model appears to constitute an important oxygen- consuming compartment. These findings show that treatment with verapamil, which increases oxygen supply through vasodilatation, may further improve tissue oxygenation by lowering oxygen consumption of the microcirculation. [ABSTRACT FROM AUTHOR]

The relationship between flow motion and tissue oxygenation was investigated during hemorrhage/retransfusion with and without dopamine in 14 pigs. During 45% bleed, jejunal microvascular hemoglobin O[sub 2] saturation (HBjO[sub 2]) and mucosal tissue Po[sub 2] (PO[sub 2muc]) were recorded in seven control and seven dopamine-treated animals. Mean arterial pressure and systemic 02 delivery decreased during hemorrhage and returned to baseline after retransfusion. Hemorrhage decreased PO[sub 2muc] from 33 ± 2.8 to 13 ± 1.6 mmHg and HBjO[sub 2] from 53 ± 4.9% to 32 ± 3.9%, respectively, in control animals. During reperfusion, PO[sub 2muc] and HBjO[sub 2] remained low. Dopamine increased PO[sub 2muc] from 28 ± 4.3 to 45 ± 4.6 mmHg and HBjO[sub 2] from 54 ± 5.7% to 69 ± 1.5% and attenuated the decrease in Po[sub 2muc] and HBjO[sub 2] during hemorrhage. After retransfusion, dopamine restored Po[sub 2muc] and HBjO[sub 2] to baseline. Control animals developed rhythmic HBjO[sub 2] oscillations with increasing amplitude (frequency, 4.5 to 7.6 cycles/min) and showed an inverse relationship between PO[sub 2muc] and HBjO[sub 2] oscillation amplitude. Dopamine prevented regular flow motion. The association between decreased Po[sub 2muc] and increased oscillations in HBjO[sub 2] after normalization of systemic hemodynamics and O[sub 2] transport in control animals suggests a cause-and-effect relationship between low tissue Po[sub 2] and flow motion activity within the jejunal microcirculation. [ABSTRACT FROM AUTHOR]

The current study aims to evaluate whether prophylactic anticoagulation using argatroban or an increased dose of unfractionated heparin (UFH) is effective in achieving the targeted activated partial thromboplastin time (aPTT) of more than 45 s in critically ill heparin-resistant (HR) patients. Patients were randomized either to continue receiving an increased dose of UFH, or to be treated with argatroban. The endpoints were defined as achieving an aPTT target of more than 45 s at 7 h and 24 h. This clinical trial was registered on clinicaltrials.gov (NCT01734252) and on EudraCT (2012-000487-23). A total of 42 patients, 20 patients in the heparin and 22 in the argatroban group, were included. Of the patients with continued heparin treatment 55% achieved the target aPTT at 7 h, while only 40% of this group maintained the target aPTT after 24 h. Of the argatroban group 59% reached the target aPTT at 7 h, while at 24 h 86% of these patients maintained the targeted aPTT. Treatment success at 7 h did not differ between the groups (p = 0.1000), whereas at 24 h argatroban showed significantly greater efficacy (p = 0.0021) than did heparin. Argatroban also worked better in maintaining adequate anticoagulation in the further course of the study. There was no significant difference in the occurrence of bleeding or thromboembolic complications between the treatment groups. In the case of heparin-resistant critically ill patients, argatroban showed greater efficacy than did an increased dose of heparin in achieving adequate anticoagulation at 24 h and in maintaining the targeted aPTT goal throughout the treatment phase. [ABSTRACT FROM AUTHOR]

Diverticulosis of the sigmoid colon is a common condition and occurs more often in elderly patients. A well-known complication is infection or even perforation which often requires surgery. Necrotizing fasciitis as a complication of perforated diverticulitis is very rare. Here, we present a case of a covered perforated diverticulitis in an immunosuppressed patient leading to life-threatening necrotizing fasciitis requiring extracorporeal membrane oxygenation. Either hematogenous or local dissemination via the inguinal canal seemed the most probable mechanism of leg infection leading to hip articulation. [ABSTRACT FROM AUTHOR]