Guidelines on suicide amongst anaesthetists 2019

Anaesthetists are thought to be at increased risk of suicide amongst the medical profession. The aims of the following guidelines are: increase awareness of suicide and associated vulnerabilities, risk factors and precipitants; to emphasise safe ways to respond to individuals in distress, both for them and for colleagues working alongside them; and to support individuals, departments and organisations in coping with a suicide.     

Efficacy and safety of adenosine in the treatment of supraventricular tachycardia in infants and children.

One hundred and seventeen episodes of supraventricular tachycardia in 50 children, including 28 infants, were treated with intravenous adenosine. Adenosine was prepared in a sterile solution of 0.9% saline (1 mg/ml) and given in incremental doses of 0.05 mg/kg every two minutes to a maximum of 0.25 mg/kg. Ninety of the 117 episodes were terminated. This included 88 of the 102 episodes of junctional tachycardia (79 of the 92 episodes of atrioventricular reentry tachycardia, seven of the eight episodes of atrioventricular nodal reentry tachycardia, and both of the episodes of long R-P' tachycardia). Only one of four episodes of His bundle tachycardia and one of the eight episodes of ectopic atrial tachycardia were terminated. None of the three episodes of atrial flutter were terminated. Side effects were frequent but mild and included transient complete atrioventricular block (less than 6 s), sinus bradycardia (less than 40 s), ventricular extrasystoles, flushing, nausea, headache, and respiratory disturbance. Reinitiation (within 5 s) of supraventricular tachycardia occurred in 13 of the terminated episodes. Although reinitiation limited its clinical efficacy in some patients, intravenous adenosine offered a safe and efficient method of rapid termination of most episodes of supraventricular tachycardia and in some cases facilitated diagnosis of the mechanism.     

Syngeneic transplantation with peripheral blood mononuclear cells collected after the administration of recombinant human granulocyte colony-stimulating factor

Five syngeneic transplants were performed in four patients following myeloablative therapy using unmodified peripheral blood mononuclear cells (PBMCs) collected after the administration of recombinant human granulocyte colony stimulating factor (rhG-CSF) to normal donors. The only toxicity experienced by the four normal donors was bone pain. Four patients received two collections of PBMCs, and a second transplant was performed in one patient with one collection. The patients received a median of 20.53 x 10(8) total nucleated cells/kg (range 20 to 25.5), 11.3 x 10(8) total mononuclear cells/kg (range 6.52 to 17.2), 113.1 x 10(4)/kg CFU-GM (range 46.7 to 211.8) and 9.6 x 10(6) CD34+ cells/kg (range 1.6 to 12.6) Post-transplant growth factors were not administered. The median time to an absolute neutrophil count greater than 0.5 x 10(9)/L was 14 days (range 10 to 18). The median time to platelet transfusion independence was 11 days (range 10 to 13). Two patients had the number of CD3+ T lymphocytes determined in the pheresis product. An average of 3.04 x 10(10) CD3+ cells were collected per pheresis. This represents an approximate 1 log increase over the number of T lymphocytes in a typical bone marrow transplant. Rh-GCSF can be used to mobilize peripheral blood progenitor cells from normal donors with minimal toxicity. Studies of allogeneic transplants using PBMCs collected after rhG-CSF administration to determine permanent grafting ability and the incidence and severity of graft-versus-host disease are warranted.     

Accuracy of endoscopic optical coherence tomography in the detection of dysplasia in Barrett's esophagus: a prospective, double-blinded study

BACKGROUND: Endoscopic optical coherence tomography (EOCT) is a high-resolution, cross-sectional tissue-imaging technique that provides microscopic morphologic information. EOCT should detect dysplasia in Barrett's epithelium, but this has not been established in a prospective blinded study. This study evaluated the accuracy of EOCT for the diagnosis and the exclusion of dysplasia in patients with Barrett's esophagus. METHODS: A 2.4-mm diameter EOCT probe was modified for use with a cap-fitted, two-channel endoscope. Pairs of EOCT image streams and jumbo biopsy specimens were obtained. Endoscopy/EOCT procedures were performed by 4 endoscopists who separately reviewed the EOCT digital images for the absence or the presence of dysplasia (low grade, high grade, or cancer) for each biopsy specimen obtained. The endoscopists were blinded to the interpretation of the pathology. An experienced pathologist blinded to the endoscopic/EOCT findings evaluated each biopsy for the absence or the presence of dysplasia. The setting of the study was a major academic medical center. Adult patients with documented Barrett's esophagus greater than 2 cm were included in the study. The main outcome measurement was the accuracy of EOCT in the detection of dysplasia in patients with Barrett's esophagus. RESULTS: A total of 314 usable EOCT image stream/biopsy pairs were obtained in 33 patients. By using histology as the standard, the performance of EOCT was sensitivity, 68%; specificity, 82%; positive predictive value, 53%; negative predictive value, 89%; and diagnostic accuracy, 78%. Diagnostic accuracy for the 4 endoscopists ranged from 56% to 98%. Limitations of the study were the variability in endoscopists' accuracy rates, difficulty in real-time interpretation, and the need for refined criteria of dysplasia by EOCT imaging. CONCLUSIONS: The current EOCT system has an accuracy of 78% for the detection of dysplasia in patients with Barrett's esophagus. EOCT could be used to target biopsies to areas of Barrett's epithelium with a higher probability for the presence of dysplasia. However, further modifications, including increased resolution and identification of further potential OCT characteristics of dysplasia, are needed before EOCT can be used clinically.     

Isoprenoid biosynthesis in the diatoms Rhizosolenia setigera (Brightwell) and Haslea ostrearia (Simonsen)

Isoprenoid biosynthesis in the widespread diatomaceous algae, Rhizosolenia setigera (Brightwell) and Haslea ostrearia (Simonsen), results not only in the production of diterpenoids, triterpenoids, and sterols but, unusually for diatoms, also in the production of sesterterpenoids. By using 13C and 2H isotopic labeling techniques followed by NMR and mass spectrometry, specific inhibition of mevalonate (MVA) and methylerythritol (MEP) pathways, and comparison with the natural 13C/12C isotope ratios of the lipids, the different biosynthetic pathways of the sesterterpenes and other isoprenoids have now been determined. Surprisingly, whereas the sesterterpenes (Delta(7(20))-haslenes) in R. setigera were made by the MVA pathway, as were the related triterpenoid rhizenes and desmosterol, in H. ostrearia the structurally similar Delta(6(17))-haslenes and the major sterol, 24-ethylcholest-5-en-3beta-ol, were instead biosynthesized by the MEP route. Phytol was biosynthesized in both diatoms by the MEP route. Subfractionation of R. setigera cells revealed that although phytol was located in the chloroplasts, the haslenes, rhizenes, and sterols were present in the cytoplasm. The observations described here for R. setigera and H. ostrearia show that terpenoid biosynthesis in diatoms is species-dependent and cannot simply be grouped according to structural type. Triterpenes appear to be made by the MVA route as in higher plants, whereas sesterterpenes and sterols can be made by either the MVA or MEP routes. In neither organism were the isoprenoids biosynthesized by leucine metabolism. Sesterterpene and triterpene biosynthesis in diatoms has not been investigated previously.