Summary Ketamine is a very versatile inexpensive drug and plays an invaluable role in the developing world. In regions where access and funding for a wider range of drugs is problematic, its broad range of clinical applications is ideal. Its good safety profile and ease of storage makes it ideal for use in areas where refrigerators, complex monitoring, electricity and oxygen may all be in short supply or unreliable. Ketamine is also finding increasing use in both the acute and chronic pain settings and research is still ongoing into a potential neuroprotective effect for ketamine in brain injury.

This is a repository copy of Effectiveness of a national quality improvement programme to improve survival after emergency abdominal surgery (EPOCH) : a stepped-wedge cluster-randomised trial. Effectiveness of a national quality improvement programme to improve survival after emergency abdominal surgery (EPOCH) : a stepped-wedge cluster-randomised trial. The Lancet. ISSN 0140-6736 https://doi.org/10.1016/S0140-6736(18)32521-2 eprints@whiterose.ac.uk https://eprints.whiterose.ac.uk/ ReuseThis article is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs (CC BY-NC-ND) licence. This licence only allows you to download this work and share it with others as long as you credit the authors, but you can't change the article in any way or use it commercially. More information and the full terms of the licence here: https://creativecommons.org/licenses/ Implications of all the available evidenceDespite the success of some smaller projects, there was no survival benefit from a national quality improvement programme to implement a care pathway for patients undergoing emergency abdominal surgery. To succeed, large national quality improvement programmes need to allow for differences between hospitals and ensure teams have both the time and resources needed to improve patient care.

Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine.

SummaryIn this study we developed a model lung to compare the effectiveness of ventilation using four different cricothyrotomy devices. The Ravussin 13G cannula (VBM Medical), the Quicktrach cannula 4 mm ID (VBM Medical), the Melker cannula 6 mm ID (Cook) and a cuffed tracheal tube 6 mm ID were used in turn to ventilate the model lung through a cricothyrotomy over a range of upper airway resistances. The 6 mm cuffed tracheal tube provided consistently good ventilation independent of upper airway resistance. The 6 mm ID Melker device provided at least reasonable and at best very good ventilation, whatever the patency of the upper airway. The Ravussin cannula could ventilate well with the jet ventilator with low upper airway resistance but could not ventilate at all with complete upper airway obstruction. The Quicktrach performed poorly with low upper airway resistance but well with increased upper airway resistance. With its easier insertion, fewer complications compared to a surgical cricothyrotomy, and the ability to use it with a standard anaesthetic circuit, the authors feel that the 6 mm Melker canula is the technique of choice for emergency trans-tracheal ventilation.

We have studied response times of 30 anaesthetists to a standardized episode of arterial oxygen desaturation in a simulated patient, randomized to the use of either a fixed or variable pitch pulse oximeter. We wished to determine if a variable auditory signal was important in detecting adverse events. A variable pitch pulse signal had a shorter time to recognition of desaturation (P < 0.0001), with a mean response time of 32 s, compared with 129 s for the fixed pitch signal.

Impingement of the tracheal tube on upper airway structures occurs commonly during advancement over a fibreoptic bronchoscope or introducer. In this descriptive study a fibrescope was used to assess the site and mechanism of tracheal tube impingement during advancement over a variety of fibreoptic bronchoscopes and introducers during orotracheal intubation in anaesthetized adults. The effect of the 90° counterclockwise rotation manoeuvre in overcoming impingement was also assessed. We recorded impingement at the right arytenoid, left arytenoid, epiglottis, interarytenoid tissue and the left pyriform fossa. Our study found a wider range of sites at which impingement may occur than in previous studies. We also found that when 90° counterclockwise rotation of the tip of the tracheal tube was achieved, the impingement was reliably overcome.

The numbers of people affected by large-scale disasters has increased in recent decades. Disasters produce a huge burden of surgical morbidity at a time when the affected country is least able to respond. For this reason an international disaster response is often required. For many years this disaster response was not coordinated. The response consisted of what was available not what was needed and standards of care varied widely producing a healthcare lottery for the affected population. In recent years the World Health organisation has initiated the Emergency Medical Team programme to coordinate the response to disasters and set minimum standards for responding teams. Anaesthetists have a key role to play in Level 2 Surgical Field Hospitals. The disaster context produces a number of logistical challenges that directly impact on the anaesthetist requiring adaptation of anaesthetic techniques from their everyday practice. The context in which they will be working and the wider scope of practice that will be expected from them in the field mandates that deploying anaesthetists should be trained for disaster response. There have been significant improvements in recent years in the speed of response, equipment availability, coordination and training for disasters. Future challenges include increasing local disaster response capacity, agreeing international standards for training and improving data collection to allow for future research and improvement in disaster response. The goal of this review article is to provide an understanding of the disaster context and what logistical challenges it provides. There has been a move during the last decade from a globally uncoordinated, unregulated response, with no consensus on standards, to a globally coordinated response through the World Health Organisation (WHO). A classification system for responding Emergency Medical Teams (EMTs) and a set of agreed minimum standards has been defined. This review outlines the scope of the role of the anaesthetist in a Level 2 field hospital and some of the challenges that this scope and context present. It focuses mainly on natural disasters, but also outline some of the differences encountered in responding to other global disasters such as conflict and infectious outbreaks, and concludes with some of the challenges for the future.

P Pu ur rp po os se e: : To study the feasibility of using the Pro-Seal laryngeal mask airway (LMA) for airway maintenance during bronchoscopic guided percutaneous tracheostomy.M Me et th ho od ds s: : Observational study of 23 patients in an 11-bed general intensive care unit. The patient's tracheal tube was exchanged for a Pro-Seal LMA before undertaking percutaneous tracheostomy.R Re es su ul lt ts s: : Inspiratory pressure and tidal volumes achieved during the procedure were recorded. The median peak inspiratory pressure was 25 (standard deviation 4.2) cm H 2 O. There was no loss of tidal volume in 11 patients, a loss of less than 100 mL·breath -1 in 11, and loss of more than 100 mL in one. A Pro-Seal LMA successfully maintained the airway and allowed adequate ventilation during percutaneous tracheostomy in all 23 patients. In all patients bronchoscopy through the Pro-Seal LMA provided a clear view of the cords and trachea and there was no laryngeal or tracheal soiling at any stage of the procedure.C Co on nc cl lu us si io on n: : The Pro-Seal LMA provides a reliable airway and allows effective ventilation during percutaneous tracheostomy. The passage of a fibrescope through the Pro-Seal LMA and glottis is easy and provides a clear view of the upper trachea. URING percutaneous dilatational tracheostomy (PDT) the patient's airway is usually maintained with a tracheal tube, which is pulled back until the cuff is lying across the vocal cords. 1,2 In this position, the tracheal tube is unstable and may become dislodged with loss of the airway and risk of aspiration. Most commonly, bronchoscopy is undertaken during the procedure to aid correct placement of the guidewire. 3 An assistant is generally required to stabilize the tracheal tube while fibreoptic examination is performed and, as the glottis is not seen, it can be very difficult to determine the level at which the cannula enters the trachea. The tip of the tracheal tube may still lie low enough within the trachea to risk cuff puncture or tube transfixion by the needle. Use of the classic laryngeal mask airway (LMA) 4-6 or the intubating LMA 7 during PDT circumvents many of these problems. However, patients requiring PDT often have poorly compliant lungs requiring high inflation pressures. Gas leak from between the LMA and glottis increases as inspiratory airway pressure rises, particularly above 20 cm H 2 O. 8 This leads to a risk of hypoventilation in patients with poorly compliant lungs. Objectif : Étudier la faisabilité de l'utilisation du masque laryngé (ML) Pro-Seal pour maintenir la perméabilité des voies aériennes pendant la trachéotomie percutanée à guidage bronchoscopique. Méthode : L'étude par observation comportait 23 patients d'une unité de soins intensifs généraux. Un ML Pro-Seal a remplacé le tube trachéal avant la trachéotomie percutanée. Résultats : La pression inspiratoire et les volumes courants obtenus pendant l'intervention ont été notés. La moyenne de la pression inspiratoire maximale a été de 25 cm H 2 O (écart type de 4,2). Il n'y a...