Public reporting of individual surgeon performance information: United Kingdom developments and Australian issues

The United Kingdom is currently introducing public reporting of performance information for individual cardiac surgeons. The reports will indicate whether a surgeon has an acceptable level of performance, measured by in-hospital mortality. In the United States, surgeon-specific performance data have been available for over a decade. Arguments from both safety and accountability perspectives provide strong justifications for public reporting of such data. Were Australia to adopt similar public reporting processes, we should learn from overseas experiences. Surgical associations should be actively involved in developing data standards and processes for data collection, validation, analysis and publication. Any Australian policy initiative for public reporting of individual surgeon data should be backed by a political commitment to adequate funding.     

Support of trigeminal sensory neurons by nonneuronal p75 neurotrophin receptors

The p75 neurotrophin receptor (p75NTR) binds all four mammalian neurotrophins, including neurotrophin-3 (NT-3) required for the development of select sensory neurons. This study demonstrated that many gustatory and somatosensory neurons of the tongue depend upon p75NTR. Each of thousands of filiform papillae at the front of the tongue as well as each somatosensory prominence at the back of the tongue has a small cluster of p75NTR-positive epithelial cells that is targeted by somatosensory innervation. This expression of p75NTR by epithelial target cells required NT-3 but not adult innervation. NT-3-secreting cells were adjacent to the p75NTR-positive target cells of each somatosensory organ, as demonstrated in NT-3(lacZneo) transgenic mice. In NT-3 null mutant mice, there were few lingual somatosensory neurons. In p75NTR null mutant mice, the lingual somatosensory axons were likewise absent or had deficient terminal arborizations. Cell culture indicated that substrate p75NTR can influence neuronal outgrowth. Specifically, dissociated trigeminal sensory neurons more than doubled their neurite lengths when grown on a lawn of p75NTR-overexpressing fibroblasts. This enhancement of neurite outgrowth by fibroblast p75NTR raises the possibility that epithelial target cell p75NTR may help to promote axonal arborization in vivo. The co-occurrence in p75NTR null mice of a 35% reduction in geniculate ganglion taste neurons and a shortfall of taste buds is consistent with the established role of gustatory innervation in prompting mammalian taste receptor cell differentiation.     

G protein-coupled receptor desensitization as a measure of signaling: modeling of arrestin recruitment to activated CCK-B receptors

Gastrin is one of the principle hormonal mediators of gastric acid secretion, and its cognate receptor (CCK-B) is a member of the superfamily of GPCRs. Patients with hypergastrinemia may present with a variety of symptoms, including gastric ulcers or malignant tumors. Thus, the molecular mechanisms that terminate CCK-B receptor signaling, as well as an ability to measure gastrin bioactivity in a timely manner, have important clinical implications. In order to assess CCK-B receptor regulation, we have constructed a single cell biosensor containing the CCK-B receptor and an arrestin/GFP chimera. The gastrin biosensor responded to both immunologically detectable gastrin-17 and undetectable pentagastrin, and was able to determine the gastrin bioactivity of serum from a patient with clinical hypergastrinemia. We determined that the CCK-B receptor binds arrestin with a pharmacology mirroring CCK-B receptor signaling through inositol phosphate, and that the rate of arrestin dissociation from internalized receptor mirrors receptor recycling to the plasma membrane. Moreover, the CCK-B recycling rate is intermediate between that of Class A GPCRs such as the beta2-adrenergic receptor and Class B GPCRs such as the vasopressin type 2 receptor. Mathematical modeling of these results indicates that a common receptor conformation may underlie both CCK-B signaling and desensitization. In addition to its use in drug screening, this methodology should generalize to other receptors for use in diagnosis and monitoring of bioactive ligands involved in GPCR-based disease.     

Intensive care of the trauma patient

Intensive care is a process and not a location and should commence as soon as major trauma is recognised. The management of severely injured patients requires all of the skills and resources of modern day intensive care medicine and can be challenging and expensive. Despite prolonged stays in the intensive care units and hospitals, the outcome for these patients is often excellent.     

Spinal cord stimulation: patient selection, technique, and outcomes

Spinal cord stimulation, as with neuromodulation procedures in general, is a nondestructive, screenable, and reversible treatment option. Because there are no long-term side effects that have been reported; spinal cord stimulation is generally preferable as a first step when other less invasive treatments have failed to produce acceptable control of the pain.     

Efficacy of continuous venovenous hemodialysis in the treatment of severe lithium toxicity

The syndrome of lithium toxicity has been well described. Hemodialysis is the recommended treatment for severe toxicity. We report a case in which continuous venovenous hemodialysis was used in the treatment of lithium toxicity. The calculated average lithium clearance was 23 mL per minute, comparing favorably with that of normal renal clearance (20-30 mL/min) and of intermittent hemodialysis (50-100 mL/min). This report discusses the potential benefits of this therapy in a hemodynamically unstable patient who may not tolerate hemodialysis.     

Evaluation of a coagulation analyzer

The CA-6000 compared favorably to the well-established 1600C in terms of clinical utility. Its enhanced reagent capacity and open nature make it a wise instrument selection option.     

Activity of pradimicin BMS-181184 against Aspergillus spp.

The pradimicins are a new class of antifungal agents with activity against the majority of human fungal pathogens. In this study, the in vitro activity of pradimicin BMS-181184 was investigated against a range of the most common species of Aspergillus. The results were compared with itraconazole and amphotericin B. BMS-181184 was found to be active against most Aspergillus spp., but at higher concentrations than itraconazole and amphotericin B.     

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.     

Evaluation of the Sheffield system for identifying children at risk from unexpected death in infancy. Results from Birmingham and Newcastle upon Tyne

The "at birth" system which is used in Sheffield to identify children likely to die unexpectedly in infancy, was tested retrospectively in Birmingham (83 cases) and in Newcastle upon Tyne (56 cases). The discrimination between cases and age-matched controls was poor in both cities. Analysis of the 8 factors used in the system showed that only 2 maintained significant case/control differences in Birmingham and Newcastle. Further investigation showed that other factors from maternity records showed significant case/control differences in these cities. Although the system used in Sheffield would not be of use in a prospective prevention programme in either Newcastle or Birmingham, the possibility of evolving an "at risk" system which might apply more widely is discussed.