Safety of intravenous metoprolol use in unmonitored wards: a single-centre observational study.

BACKGROUND AND AIM: This study aims to examine and quantify the risks associated with the use of intravenous metoprolol on unmonitored wards. METHOD: This study was a retrospective single-centre observational study from 1 January 2009 to 31 December 2013. The study hospital was a 415-bed, private hospital in Melbourne, Victoria. The study population was all patients who received intravenous metoprolol on an unmonitored ward. The primary outcome measure was the rate of serious adverse events (SAE), defined as a complication of intravenous metoprolol resulting in transfer to a critical-care environment, a medical emergency team call or death. RESULTS: Six hundred and nine patients received a total of 8260 doses of intravenous metoprolol. Seven cases were identified with a SAE deemed possibly related to beta-blocker use and there was one death. All SAE were hypotension, giving an overall rate of hypotension of 7/609 or 1.1% (95% confidence interval (CI), 0.5 to 2.4%) with a rate per dose delivered of 0.8/1000 doses (95% CI 0.3 to 1.7). The death occurred in a 94-year-old woman with abdominal sepsis. After case file review, consensus opinion deemed this to be unrelated to intravenous metoprolol. CONCLUSION: The use of intravenous metoprolol on unmonitored wards appears to be safe. The complication rate was low, suggesting that this may be a sensible approach to the management of in-hospital populations at risk of beta-blocker withdrawal.

Variation in functional pelvic tilt in patients undergoing total hip arthroplasty.

AIMS: The pelvis rotates in the sagittal plane during daily activities. These rotations have a direct effect on the functional orientation of the acetabulum. The aim of this study was to quantify changes in pelvic tilt between different functional positions. PATIENTS AND METHODS: Pre-operatively, pelvic tilt was measured in 1517 patients undergoing total hip arthroplasty (THA) in three functional positions - supine, standing and flexed seated (the moment when patients initiate rising from a seated position). Supine pelvic tilt was measured from CT scans, standing and flexed seated pelvic tilts were measured from standardised lateral radiographs. Anterior pelvic tilt was assigned a positive value. RESULTS: The mean pelvic tilt was 4.2° (-20.5° to 24.5°), -1.3° (-30.2° to 27.9°) and 0.6° (-42.0° to 41.3°) in the three positions, respectively. The mean sagittal pelvic rotation from supine to standing was -5.5° (-21.8° to 8.4°), from supine to flexed seated was -3.7° (-48.3° to 38.6°) and from standing to flexed seated was 1.8° (-51.8° to 39.5°). In 259 patients (17%), the extent of sagittal pelvic rotation could lead to functional malorientation of the acetabular component. Factoring in an intra-operative delivery error of ± 5° extends this risk to 51% of patients. CONCLUSION: Planning and measurement of the intended position of the acetabular component in the supine position may fail to predict clinically significant changes in its orientation during functional activities, as a consequence of individual pelvic kinematics. Optimal orientation is patient-specific and requires an evaluation of functional pelvic tilt pre-operatively. Cite this article: Bone Joint J 2017;99-B:184-91.

Ultrastructure of synapses in the cerebellar cortex after long-term activation of climbing fibres.

Adult male rats were treated for 24 or 48 h with harmaline which selectively activates neurones in the inferior olivary nucleus which give rise to climbing fibres projecting to the cerebellar vermis. Electrophysiological studies have shown that harmaline-induced climbing fibre activity completely blocks the responses of the Purkinje cell to parallel fibre input. Morphometric analysis of the ultrastructure of climbing and parallel fibre synapses revealed no significant differences in morphology between vermis (experimental) and hemisphere (control). These findings indicate that the decreased responsiveness of Purkinje cells to parallel fibre inputs induced by increased climbing fibre activity over 24 or 48 h is not accompanied by any observable structural changes in the cerebellar cortex.

Cardiovascular, haematological and neurological effects of the venom of the Papua New Guinean small-eyed snake (Micropechis ikaheka) and their neutralisation with CSL polyvalent and black snake antivenoms.

Cardiovascular and haematological effects of venom of the small-eyed Snake (Micropechis ikaheka) were examined in ventilated anaesthetised piglets. Neurotoxic effects were examined in chick biventer cervicis nerve-muscle preparations. Immunoreactivity of venom was tested against the monovalent antivenom components in a CSL Ltd Venom Detection Kit. Neutralisation was tested in vivo and in vitro with CSL Ltd polyvalent snake and Black Snake (Pseudechis australis) antivenoms. Venom in 0.1% bovine serum albumin in saline was infused into piglets in doses 1-2000 microg/kg. Pulmonary hypertension (P= 0.0007) and depression of cardiac output (P= 0.002) were observed up to 3 h after 150-160 microg/kg. The concentration of plasma free-haemoglobin increased more than 50-fold, indicating haemolysis. Neither coagulopathy nor thrombocytopenia occurred. Creatine phosphokinase and serum potassium levels did not increase suggesting absence of acute rhabdomyolysis. The venom caused post-synaptic neurotoxicty. Immunoreactivity of venom with Black Snake antivenom was observed at very high venom concentrations. Cardiovascular effects were absent and haemolysis was less after venom was pre-incubated at 37 degrees C for 30 min with polyvalent antivenom. Neutralisation by Black Snake antivenom was less effective. The neurotoxicity was neutralised by polyvalent or Black Snake antivenoms. Human envenomation may be treated with CSL Ltd polyvalent snake antivenom.

Venomous marine creatures.

BACKGROUND: Many venomous marine creatures inhabit Australian waters, causing significant morbidity and occasional fatalities. No antivenom is available for most of these creatures. Little is known about the venom or syndromes produced by many of these creatures. OBJECTIVE: This article discusses the features of envenomation by some of the more commonly encountered venomous marine creatures, and the recommended first aid and medical management of such envenomations. DISCUSSION: The information contained within this article is intended to provide the reader with an overview of some of the more common marine envenomations, and hopefully with the knowledge to effectively manage such problems.

Spider bite. A rational approach.

BACKGROUND: Spider bite is one of the most common envenomation problems in Australia. Australia is home to two spiders of major medical importance; the Sydney funnel web spider and the redback spider. OBJECTIVE: This paper describes the features of envenomation and discusses treatment for bites by the Sydney funnel web spider and the redback spider. Bites by other spiders are also discussed, as is the problem of necrotising arachnidism. DISCUSSION: It is hoped that the information contained within this article will be of help to medical practitioners dealing with spiderbite throughout Australia. There is, as yet, a great deal to be learned about spiderbite, particularly necrotising arachnidism.

Could this be snakebite?

BACKGROUND: Australian snakes are among the most venomous in the world. Although usually obvious, the occurrence of snakebite is occasionally unrecognised by the patient and/or physician, resulting in delayed or inadequate treatment, or even in death. OBJECTIVE: This article describes the historical, clinical and pathologic features associated with envenomation by various Australian venomous snakes, and discusses the investigation and management (including first aid) of suspected snakebite. DISCUSSION: A high index of suspicion should be maintained, particularly in rural areas and in patients unable to give a history. Investigations including creatine kinase, clotting profile and venom detection kit should be performed in cases of suspected snakebite. The choice of appropriate antivenom and its indications are discussed.

Acute and recurrent skin ulceration after spider bite.

We reviewed the records of the Australian Venom Research Unit and The Alfred Hospital Department of Hyperbaric Medicine from January 1992 to July 1998 and found 15 cases of skin ulceration after spider bite that could be followed up with the patient and the treating physician. Fourteen patients had skin ulceration attributed to white-tailed spider bites but in only three was this confirmed. One patient had skin necrosis after a confirmed black house spider bite. Recurrent skin ulceration occurred in nine of the 15 patients.

Funnel-web spider (Hadronyche infensa) envenomations in coastal south-east Queensland.

Five patients with confirmed funnel-web spider bites (Hadronyche infensa) presented to Nambour General Hospital, in south-east Queensland, between 1992 and 1998. Two patients required antivenom; low doses of antivenom were effective. Patients were bitten in spring and early summer. In areas such as this, where funnel-web spider bites are reported less frequently than in New South Wales, clinicians and the community should be aware of the risks and immediate management of these bites.