Postoperative small bowel and colonic anastomotic bleeding. Therapeutic management and complications.

INTRODUCTION: Postoperative small bowel or colic anastomotic bleeding (PSCAB) is often a mild complication and is generally treated by a conservative approach. Other therapeutic options are surgery, endoscopic management and angiographic embolization. Our aim is to review our cases of postoperative anastomotic bleeding in patients with small bowel or colic anastomosis, with special attention to their treatment and complications. PATIENTS AND METHODS: Observational retrospective study including patients with PSCAB in the department of General and Digestive Surgery in Vall d'Hebron University Hospital, between 2007 and 2012. Demographic and bleeding characteristics as well as therapeutic management were reviewed, including complications derived from the different therapeutic options. RESULTS: There were 44 cases of bleeding after performing small bowel or colic anastomosis, 25 patients were men (56.8%), with a mean age of 68.2 years (R: 28-92). The mean hematocrit decrease was 8 points (R: 0-17), and hemodynamic instability was detected in 13 patients (29.5%). A conservative management was undertaken in 27 patients (61.3%), surgery in 6 (13.6%), endoscopic treatment in 2 (4.5%) and embolization in 9 (20.5%). 4 patients of cases treated with embolization presented anastomotic leak (44.5%). Mortality was 13.6% (6 patients). A total of 4 of 6 deaths were in the group of patients treated with embolization. CONCLUSIONS: Most patients with PSCAB have a good response to conservative management. When there is failure of this approach, there are different therapeutic options, including angiographic embolization. In our series, we have seen a high incidence of post embolization anastomotic leak; further trials will be necessary to provide valuable evidence of the risk of this therapeutic option.

Hexose-specificity of hexokinase and ADP-dependence of pyruvate kinase play important roles in the control of monosaccharide utilization in freshly diluted boar spermatozoa.

Incubation of boar sperm from fresh ejaculates in a minimal medium with 10 mM glucose induced a fast and intense activation of glycolysis, as indicated by the observed increases in the intracellular levels of glucose 6-phosphate (G 6-P) and ATP and the rate of formation of extracellular L-lactate. The effect of glucose was much more intense than that induced by fructose, sorbitol, and mannose. The greater utilization of glucose was related to a much greater sensitivity to hexokinase when compared with the other monosaccharides. Thus, the presence of 0.5 mM glucose induced total hexokinase activity in supernatants from sperm extracts of 1.7 +/- 0.1 mIU/mg protein, while the same concentration of both fructose, mannose, and sorbitol induced total hexokinase activity from 0.3 +/- 0.1 mIU/mg protein to 0.60 +/- 1 mIU/mg protein. Kinetic analysis of the total pyruvate kinase activity indicated that this activity was greatly dependent on the presence of ADP and also showed a great affinity for PEP, with an estimated Km in supernatants of 0.15-0.20 mM. Immunological location of proteins closely related to glycolysis, like GLUT-3 hexose transporter and hexokinase-I, indicated that these proteins showed the trend to be distributed around or in the cellular membranes of both head and midpiece in a grouped manner. We conclude that glycolysis is regulated by both the specific availability of a concrete sugar and the internal equilibrium between ATP and ADP levels. Furthermore, localization of proteins involved in the control of monosaccharide uptake and phosphorylation suggests that glycolysis starts at concrete points in the boar-sperm surface.

Utilization of citrate and lactate through a lactate dehydrogenase and ATP-regulated pathway in boar spermatozoa.

Incubation of boar spermatozoa in Krebs-Ringer-Henseleit medium with either 10 mM lactate or 10 mM citrate induced a fast and robust increase in the intracellular levels of ATP in both cases, which reached a peak after 30 sec of incubation. Utilization of both citrate and lactate resulted in the export of CO(2) to the extracellular medium, indicating that both substrates were metabolized through the Krebs cycle. Incubation with citrate resulted in the generation of extracellular lactate, which was inhibited in the presence of phenylacetic acid. This indicates that lactate is produced through the pyruvate carboxylase step. In addition, there was also a significant increase in tyrosine phosphorylation induced by both citrate and lactate. Boar sperm has a sperm-specific isoform of lactate dehydrogenase (LDH), mainly located in the principal piece of the tail. Kinetic studies showed that boar sperm has at least two distinct LDH activities. The major activity (with an estimated Km of 0.51 mM) was located in the supernatants of sperm extracts. The minor LDH activity (with an estimated Km of 5.9 mM) was associated with the nonsoluble fraction of sperm extracts. Our results indicate that boar sperm efficiently metabolizes citrate and lactate through a metabolic pathway regulated by LDH.

The presence of a high-Km hexokinase activity in dog, but not in boar, sperm.

The presence of a high-Km hexokinase activity was tested in both dog and boar spermatozoa. Hexokinase kinetics from dog extracts showed the presence of a specific activity (dog-sperm glucokinase-like protein, DSGLP), in the range of glucose concentrations of 4-10 mM, whereas boar sperm did not show any DSGLP activity. Furthermore, dog-sperm cells, but not those of boar, showed the presence of a protein which specifically reacted against a rat-liver anti-glucokinase antibody. This protein also had a molecular weight equal to that observed in rat-liver extracts, suggesting a close similarity between both the proteins. This glucokinase-like protein was distributed in the peri- and post-acrosomal zones of the head, and the midpiece and principal piece of tail of dog spermatozoa. These results indicate that dog spermatozoa have functional high-Km hexokinase activity, which could contribute to a very fine regulation of their hexose metabolism. This strict regulation could ultimately be very important in optimizing dog-sperm function along its life-time.

Metabolic strategy of boar spermatozoa revealed by a metabolomic characterization.

Metabolomic characteristics in boar spermatozoa were studied using [1,2-(13)C(2)]glucose and mass isotopomer analysis. In boar spermatozoa, glycolysis was the main pathway of glucose utilization producing lactate/pyruvate, whereas no gluconeogenesis was seen. Slight glycogen synthesis through the direct pathway and some incorporation of pyruvate into the Krebs cycle also took place. Neither RNA ribose-5-phosphate nor fatty acid synthesis from glucose occurred despite the detection of pyruvate dehydrogenase activity. In contrast to the known metabolic activities in dog sperm, boar spermatozoa have low levels of energy production and biosynthetic activities suggesting two different metabolic profiles for the two different phenotypes.