Anaesthesia and intensive care
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Anaesth Intensive Care · Dec 2007
Propofol-induced changes in myoplasmic calcium concentrations in cultured human skeletal muscles from RYR1 mutation carriers.
Malignant hyperthermia is a pharmacogenetic disorder caused by autosomal dominant mutations in the ryanodine receptor type 1 gene. Propofol has been reported as a safe anaesthetic for malignant hyperthermia susceptible patients but has not been tested on cultured cells from patients with the ryanodine receptor type 1 mutation. The aim of this study was to determine whether propofol could trigger abnormal calcium fluxes in human myotubes isolated from malignant hyperthermia susceptible patients harbouring the native ryanodine receptor type 1 mutation. ⋯ The half-maximal activation concentrations (EC50) for propofol from patients 1 and 2 were 181.1 and 420.5 microM, respectively. Increases in calcium concentrations in response to propofol dosage were limited to doses at least 100-fold greater than those used in clinical settings. These observations correlate well with clinical observations that propofol does not trigger malignant hyperthermia in susceptible humans.
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Anaesth Intensive Care · Dec 2007
Perioperative complications in patients with drug-eluting stents: a three-year audit at Geelong Hospital.
Drug-eluting stents are a recommended treatment for lesions in the coronary arteries. Stent insertion requires the patient remain on anti-platelet medication for a minimum of six months after insertion. A serious consequence of ceasing anti-platelet medication is late stent thrombosis leading to myocardial infarction in the territory of the drug-eluting stent. ⋯ The risk of myocardial infarction when clopidogrel is stopped prior to surgery is 20%, if alternative anti-thrombotic prophylaxis is not used. This risk persists beyond one year after insertion of drug-eluting stents. Some treatments appear to be effective in reducing the risk of myocardial infarction.
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Anaesth Intensive Care · Dec 2007
Case ReportsSupplemental jet ventilation in conscious patients following major oesophageal surgery.
Intensive care unit patients are at particular risk of respiratory failure after major abdominal surgery. Non-invasive ventilation or application of continuous positive airway pressure through a face mask may stabilise respiratory function and avoid the need for endotracheal re-intubation. However; there are various contraindications to non-invasive ventilation and/or tracheal re-intubation, such as recent oesophageal anastomosis, anastomotic leakage or tracheal stenting for tracheo-oesophageal fistula. A specific management strategy consisting of continuous intratracheal jet ventilation to support spontaneous respiratory function is described in two patients with contraindications to non-invasive ventilation or mask continuous positive airway pressure after major oesophageal surgery.
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Anaesth Intensive Care · Dec 2007
Comparative StudyA comparison of 4% succinylated gelatin solution versus normal saline in stable normovolaemic sheep: global haemodynamic, regional blood flow and oxygen delivery effects.
The objective of this study was to compare the effects on regional blood flow and regional oxygen delivery of 4% succinylated gelatin solution (Gelofusine, B. Braun) with those of normal saline. This was a randomised, controlled, cross-over large animal study, which took place at the animal laboratory of university physiology institute. ⋯ Normal saline and Gelofusine have transient, volume expansion-related systemic haemodynamic effects, which are greater for Gelofusine. Saline had a more pronounced early effect on mesenteric blood flow, while Gelofusine had a sustained and progressive greater effect on renal blood flow. The transient increase in urine output and creatinine clearance seen with both fluids occurred while renal oxygen delivery decreased.
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Anaesth Intensive Care · Dec 2007
The preoperative detection of risk of anaphylaxis during anaesthesia.
In 144 patients who were referred to an anaesthetic allergy clinic because of perceived risk of anaphylaxis during anaesthesia, the only 'at risk' group that could be identified was patients with a history of unexplained severe adverse reaction during previous anaesthesia. Twenty-two of 45 patients with such a history had positive skin tests to an anaesthetic drug. ⋯ On the contrary, investigation of patients without a previous adverse reaction did not appear to be of value. These findings suggest that those patients with a history of a severe undiagnosed adverse event during previous anaesthesia should be investigated with preoperative skin-testing before undergoing further elective surgery.