Umbilically and Peripherally Inserted Thin Central Venous Catheters Have Similar Risks of Complications in Very Low-Birth-Weight Infants.

Catheter complications can be life-threatening in very low-birth-weight (VLBW) infants. We retrospectively evaluated non-elective removals of the first thin (1-2F) umbilical vein catheters (tUVCs (n = 92)) and peripherally inserted central venous catheters (PICCs (n = 103)) among 195 VLBW infants. Catheters were removed non-electively in 78 infants (40%), typically due to suspected infection (n = 42) or catheter dislocation (n = 30). Infants with complications had lower birth weights and gestational ages than others. The frequencies and causes of catheter removal were similar in the tUVC and PICC groups. Thirty-one infants had true catheter infections. The number of infections/1000 catheter days was higher in the tUVC group than in the PICC group. In a multivariable analysis, gestational age was associated with catheter infection, but catheter type was not. The odds of catheter complications decreased with increasing gestational age, but no clear association with thin catheter type was found.

Atipamezole increases medetomidine clearance in the dog: an agonist-antagonist interaction.

Medetomidine, an alpha 2-adrenoceptor agonist, is a potent sedative and analgesic agent in the dog. When necessary, its action can be effectively antagonized by atipamezole. The present work was designed to study the effects of these drugs on each others' pharmacokinetics when a single intramuscular dose of medetomidine (50 micrograms kg-1) was followed by a dose of atipamezole (250 micrograms kg-1). Three different treatments were used: medetomidine alone, atipamezole alone, and atipamezole after medetomidine. Drug concentrations in plasma were measured by GC-MS. Statistical analysis of the results (ANOVA) revealed significant differences between treatments in the kinetic parameters of medetomidine. Atipamezole decreased the AUC of medetomidine from 41.3 to 28.6 ng h ml-1 (P = 0.005), t1/2 from 1.44 to 0.87 h (P = 0.015), and increased Cl from 21 to 31 ml min-1 kg-1 (P = 0.017). Differences in Vz did not reach statistical significance. The only statistically significant effects of medetomidine on the pharmacokinetics of atipamezole in this study were the slight decrease of Cl and Cmax as well as the increase of AUC. It is suggested that the large dose of medetomidine used caused haemodynamic changes, resulting in decreased hepatic circulation and slower drug metabolism. Antagonism by atipamezole restored the hepatic blood flow and, consequently, increased the elimination of medetomidine by biotransformation.

On the metapsychology of schizophrenia.

The author's point of departure is schizophrenic fragmentation, which has been considered here from a drive-economic and structural point of view, starting from Freud's prestructural conceptions and Jacobson's metapsychological formulations. The view is arrived at in the essay that the central psychological mechanism in the schizophrenic disorder is a drive-energetic decathexis of the basic psychic tissue, or the primal representative matrix, which has far-reaching consequences within the entire psychic organization. The basic psychic tissue corresponds to that area of inner reality which, according to Freud, remains beyond the primal repression and is made up of the first representations of the instinctual drive. The entire psychic organization has then been woven out of this representational tissue, binding drive energies in a preliminary way. According to the view put forward here, schizophrenic fragmentation does not primarily represent a disintegration of the psychic macrostructures or a consequence of the ego's resorting to primitive defences but is a consequence of a drive-energetic crisis at the level of the basic psychic tissue. The disorder manifests itself as the disappearance of inner liveliness and as a diffuse dissociation of the entire representional world, which I have characterized as the disappearance of psychic transparence. Its influences naturally also extend to the realm of the more advanced psychic functions and macrostructures and will invalidate in a radical way the person's drive economy. Reference is made in the article to the possibility that the central task of the primal representative matrix may be the creation of lively connexions and a striving for synthesis throughout the entire psychic organization and that the schizophrenic disorder may be intimately related to the decathexis of this function.