Background Midazolam is a benzodiazepine commonly used in procedural sedation and general anaesthesia. Current anaesthetic guidelines advise the avoidance of benzodiazepines in elderly patients due to concerns of an increased risk of delirium. Delirium is associated with significant patient morbidity and mortality, while also increasing health costs. Despite this, midazolam is often used in elderly patients undergoing low risk procedures due to the benefits of rapid onset, anxiolysis and haemodynamic stability compared to other sedatives. To date, studies describing the relationship between midazolam use and delirium in elderly patients undergoing low risk procedures, such as endoscopy, are limited. Method This was a prospective observational cohort pilot study identifying the prevalence of delirium pre-procedure and incidence of delirium post-procedure in elderly endoscopy patients receiving midazolam. The study population was elderly patients greater than 65 years of age, without underlying cognitive dysfunction, undergoing elective endoscopy. Electronic databases were used for collection of demographic and clinical information. Delirium was identified through the administration of the Family Confusion Assessment Method survey; this was administered to carers of the study population 24–48 h pre and post procedure to categorically identify the presence or absence of delirium. Results Fifty-eight participants were recruited for this study and eighteen were subsequently excluded based upon additional exclusion criteria. Forty patients were included in the final results. American Society of Anaesthesiology Classification (ASA) of patients were as follows: 1 (9 patients), 2 (12 Patients), 3 (16 Patients) and 4 (3 patients). Patients underwent gastroscopy, colonoscopy or combined gastroscopy and colonoscopy. This study identified no cases of delirium in elderly patients after administration of midazolam for elective endoscopy procedures 24–48 h post-procedure. Additionally, a high proportion of elderly patients were found to have received midazolam. Conclusion No episodes of delirium were identified in this study. This finding runs counter to current guideline recommendations regarding midazolam use in the elderly patient and that elderly patients undergoing elective endoscopy represent a significantly different patient population compared to those previously studied. This study suggests that in the study population that the risk of delirium in patients exposed to midazolam in elective endoscopy was not demonstrated and that it may be safe to perform experimental studies to elucidate the safety of midazolam in larger studies.

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The issues of caprock integrity have been thrust into the forefront of consideration and regulation. There have been several documented steam and bitumen leaks to surface and recently the AER has placed a moratorium on the licensing of shallow thermal in-situ oilsand projects. They have also sent out a series of draft requirements. In the interim, the draft letters are a good indicator of future requirements.A brief description will be made of the main technical issues in determining caprock integrity. A detailed discussion will also be made of the 5 separate documents issued by the AER. A practical approach to deal with these technical and regulatory requirements will be outlined. The foundation of all of this analysis is a good understanding of the conditions in the ground. The paper will concentrate on core acquisition, storage, analysis and preservation from the drill site to the laboratory. This is the starting point for laboratory testing, MOP determination, geomechanical modelling and thermal reservoir simulation.Failure to properly quantify the geomechanical properties and in-situ stress can increase the potential for failure. This could end a project, tie up capital, produce environmental liabilities and risk public safety. Responsible development of thermal projects requires that caprock integrity be quantified. Geomechanical Processes in SAGDThere are numerous processes that occur in a SAGD operation, which affects the geomechanical response of caprock. Figure-1 illustrates the influence of the SAGD operation on the geomechanical processes in the subsurface and at the ground surface. Geological and mechanical properties of the strata also influence the geomechanical processes in a system.The main forces that will be discussed include:• Thermal expansion -which increases stresses in the heated zone.

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