Diagnosis and management of respiratory adverse events in the operating room

Perioperative respiratory adverse events cause more than three-quarters of all perioperative critical incidents in pediatric anesthesia and approximately half of anesthesia-related cardiac arrests. We can define seven main clinical types of perioperative respiratory adverse events: upper airway obstruction, laryngospasm, bronchospasm, severe persistent cough, apnea, stridor, and oxygen desaturation. Depending on the definitions used for preoperative respiratory adverse events and the cohort of children examined, the incidence varies between 8 and 21 %. This review discusses the recognition and treatment of perioperative respiratory adverse events. Furthermore, it provides guidance on how to identify children who are at increased risk for developing perioperative respiratory adverse events and how to tailor the perioperative anesthetic management for the individual child in order to minimize the risk of perioperative respiratory adverse events

A 10-year experience in paediatric spontaneous cerebral hemorrhage: which children with headache need more than a clinical examination?

INTRODUCTION: When a child is seen in a clinic with a headache, stroke is certainly not the first on the list of differential diagnoses. In western countries, stroke is typically associated with adults and the elderly. Although rare, haemorrhagic strokes are not exceptional in the paediatric population, as their incidence is around 1/100 000/year. Prompt diagnosis is essential, since delayed treatment may lead to disastrous prognosis in these children. MATERIALS AND METHODS: This is a retrospective review of paediatric cases with spontaneous cerebral haemorrhage that presented in two university hospitals in the last ten years. The experience of these primary and tertiary referral centres comprises 22 consecutive cases that are analysed according to aetiology, presenting symptoms, treatment and outcome. RESULTS: 77% of the children diagnosed with haemorrhagic stroke presented with headaches. 41% of them had a sudden onset, while 9% developed headaches over a period of hours to weeks. While 9% presented only with headaches, the majority had either subtle (diplopia, balance problems) or obvious (focal deficits, unilateral weakness and decreased level of consciousness) concomitant neurological signs. 55% had an arteriovenous malformation (AVM), 18% had an aneurysm and 14% had a cavernous malformation. In 14% the aetiology could not be determined. The majority of haemorrhages (82%) were supratentorial, while 18% bled into the posterior fossa. All children underwent an emergency cerebral CT scan followed by specific investigations. The treatment was dependent on the aetiology as well as the mass effect of the haematoma. In 23% an emergent evacuation of the haematoma was performed. Two children (9%) died, and 75% had a favourable clinical outcome. CONCLUSION: Headaches in children are a common problem, and a small minority may reveal an intracranial haemorrhage with poor prognosis if not treated promptly. Although characterisation of headaches is more difficult in a paediatric population, sudden, unusual or intense headaches should lead to imaging work-up. Any neurological finding, even one as subtle as hemianopsia or dysmetria, should alarm the physician and should be followed by emergency imaging investigation. If the cerebral CT reveals a haemorrhage, the child should be referred immediately to a neurosurgical referral centre without further investigation. The outcome is grim for children presenting in coma with fixed, dilated pupils. The long-term result overall for children after spontaneous intracranial haemorrhage is not dismal and depends critically on specialised management

Effect of obesity and thoracic epidural analgesia on perioperative spirometry

Background. Lung volumes in obese patients are reduced significantly in the postoperative period. As the effect of different analgesic regimes on perioperative spirometric tests in obese patients has not yet been studied, we investigated the effect of thoracic epidural analgesia and conventional opioid-based analgesia on perioperative lung volumes measured by spirometry. Methods. Eighty-four patients having midline laparotomy for gynaecological procedures successfully completed the study. Premedication, anaesthesia and analgesia were standardized. The patients were given a free choice between epidural analgesia (EDA) (n=42) or opioids (n=42) for postoperative analgesia. We performed spirometry to measure vital capacity (VC), forced vital capacity, peak expiratory flow, mid-expiratory flow and forced expiratory volume in 1 s at preoperative assessment, 30-60 min after premedication and 20 min, 1 h, 3 h and 6 h after extubation. Results. Baseline values were all within the normal range. All perioperative spirometric values decreased significantly with increasing body mass index (BMI). The greatest reduction in VC occurred directly after extubation, but was less in the EDA group than in the opioid group: mean of −23(sd 8)% versus −30(12)% (P30) the difference in VC was significantly more pronounced than in patients of normal weight (BMI<25): −45(10)% versus −33(4)% (P<0.001). Recovery of spirometric values was significantly quicker in patients receiving EDA, particularly in obese patients. Conclusion. We conclude that EDA should be considered in obese patients undergoing midline laparotomy to improve postoperative spirometr

Effect of obesity and site of surgery on perioperative lung volumes

Background. Although obese patients are thought to be susceptible to postoperative pulmonary complications, there are only limited data on the relationship between obesity and lung volumes after surgery. We studied how surgery and obesity affect lung volumes measured by spirometry. Methods. We prospectively studied 161 patients having either breast surgery (Group A, n=80) or lower abdominal laparotomy (Group B, n=81). Premedication and general anaesthesia were standardized. Spirometry was measured with the patient supine, in a 30° head‐up position. We measured vital capacity (VC), forced vital capacity, peak expiratory flow and forced expiratory volume in 1 s at preoperative assessment (baseline), after premedication (before induction of anaesthesia) and 10-20 min, 1 h and 3 h after extubation. Results. Baseline spirometric values were all within the normal range. All perioperative values decreased significantly with increasing body mass index (BMI). The greatest reduction of mean VC (expressed as percentage of baseline values) occurred after extubation, and was more marked after laparotomy than after breast surgery (23 (sd 14)% vs 20 (14)%). Considering patients according to BMI (30), VC decreased after surgery by 12 (7)%, 24 (8)% and 40 (10)%, respectively. VC recovered more rapidly in Group A. Conclusion. Postoperative reduction in spirometric volumes was related to BMI. Obesity had more effect on VC than the site of surgery. Br J Anaesth 2004; 92: 202-

Business-IT-Alignment in Gemeinden – Qualitative Forschung anhand dreier größerer Berner Gemeinden

Durch die elektronische Vernetzung und die zunehmende Komplexität der IT in Verwaltungsorganisationen und insbesondere Gemeinden nimmt die Bedeutung des Business-IT- Alignments (BIA) zu. Je besser die Ausrichtung der IT am Business, so die Annahme, desto höher ist die Nutzenstiftung durch die IT. Allerdings wird dem BIA sowohl von Firmen als auch öffentlichen Verwaltungen häufig immer noch zu wenig Beachtung geschenkt [LB99], [LPB99]). Eine frühere Untersuchung zeigte, dass bei großen Gemeinden das BIA in der Regel besser ausgebildet ist als bei kleinen [BET13], [WEB14]. Aus diesem Grund beschäftigt sich der vorliegende Beitrag mit dem Thema BIA bei drei großen anonymisierten Berner Gemeinden A, B und C. Deren BIA wird qualitativ und auf Basis eines auf Basis der Literatur abgeleiteten spezifischen Reifegradmodells für das BIA in Gemeinden untersucht. Basierend auf Letzterem erfolgt die Ableitung eines Interviewleitfadens. Das Ziel des vorliegenden Beitrags ist es, die Ausprägungsund Wirkungsarten des strategischen und operativen BIA in großen Gemeinden vertiefter zu untersuchen. Im Hauptteil des vorliegenden Beitrags werden die verschiedenen BIA-Ausprägungen der untersuchten Gemeinden analysiert. Mittels des entwickelten Reifegradmodells ist feststellbar, welche Ausprägung das BIA den Gemeinden hat. Aus der Analyse geht hervor, dass die Reifegradkriterien bezogen auf die Informatik-Abteilungen der untersuchten Gemeinden einen tiefen bis mittleren Reifegrad aufweisen. Dies ist u.a. darauf zurückzuführen, dass die vorhandenen Strategie-Dokumente keinen Bezug zu Legislaturzielen der Gemeinden haben und dazu auch keinen Beitrag leisten. Weiter mangelt es teilweise an der Zusammenarbeit und der Kommunikation mit den internen Informatikkunden (Direktionen). Auch operative Gremien werden als Mittel zum BIA nicht bestmöglich eingesetzt. Zudem sehen sich die Informatik-Abteilungen häufig selbst nur als Dienstleister und Enabler, was ihr Verhalten beeinflusst und sie im proaktiven Handeln hemmt

Feature Recognition for Interactive Applications: Exploiting Distributed Resources

The availability of low-cost computational power is a driving force behind the growing sophistication of CAD software. Tools designed to reduce time-consuming build-test-redesign iterations are essential for increasing engineering quality and productivity. However, automation of the design process poses many difficult computational problems. As more downstream engineering activities are being considered during the design phase, guaranteeing reasonable response times within design systems becomes problematic. Design is an interactive process and speed is a critical factor in systems that enable designers to explore and experiment with alternative ideas during the design phase. Achieving interactivity requires an increasingly sophisticated allocation of computational resources in order to perform realistic design analyses and generate feedback in real time. This paper presents our initial efforts to develop techniques to apply distributed algorithms to the problem of recognizing machining features from solid models. Existing work on recognition of features has focused exclusively on serial computer architectures. Our objective is to show that distributed algorithms can be employed on realistic parts with large numbers of features and many geometric and topological entities to obtain significant improvements in computation time using existing hardware and software tools. Migrating solid modeling applications toward a distributed computing framework enables interconnection of many of the autonomous and geographically diverse software tools used in the modern manufacturing enterprise. (Also cross-referenced as UMIACS-TR-94-126.1

Manufacturing-Operation Planning Versus AI Planning

Although AI planning techniques can potentially be useful in several manufacturing domains, this potential remains largely unrealized. Many of the issues important to manufacturing engineers have now seemed interesting to AI researchers -- but, in order to adapt AI planning techniques to manufacturing, it is important to address these issues in a realistic and robust manner. Furthermore, by investigating these issues, AI researchers may be able to discover principles that are relevant for AI planning in general. As an example, in this paper we describe the techniques for manufacturing- operation planning used in IMACS (Interactive Manufacturability Analysis and Critiquing System). We compare and contrast them with the techniques used in classical AI planning systems, and point out that some of the techniques used in IMACS may also be useful in other kinds of planning problems. (Also cross-referenced as UMIACS-TR-95-3

Integrating DFM with CAD through Design Critiquing

The increasing focus on design for manufacturability (DFM) in research in concurrent engineering and engineering design is expanding the scope of traditional design activities in order to identify and eliminate manufacturing problems during the design stage. Manufacturing a product generally involves many different kinds of manufacturing activities, each having different characteristics. A design that is good for one kind of activity may not be good for another, for example, a design that is easy to assemble may not be easy to machine. One obstacle to DFM is the difficulty involved in building a single system that can handle the various manufacturing domains relevant to a design. In this paper we propose an architecture for integrating CAD with DFM. As the designer creates a design multiple critiquing systems analyze its manufacturability with respect to different manufacturing domains such as machining, fixturing, assembly, and inspection. Using this analysis, each critiquing system offers advice about potential ways of improving the design and an integration module mediates conflicts among the different critiquing systems in order to provide feedback to improve the overall design. We anticipate that this approach can be used to build a multi-domain environment that will allow designers to create higher-quality products that can be more economically manufactured. This will reduce the need for redesign and reduce product cost and lead time. (Also cross-referenced as UMIACS-TR-94-96

Management of brainstem haemorrhages

Among spontaneous intracranial haemorrhages, primary non-traumatic brainstem haemorrhages are associated with the highest mortality rate. Patients classically present with rapid neurological deterioration. Previous studies have found that the severity of initial neurological symptoms and hydrocephalus are predictors of poor outcomes. In addition, radiological parameters aim to classify brainstem haematomas according to volume, extension and impact on prognosis. However, previous studies have failed to agree on a differentiated radiological classification for outcome and functional recovery. Electrophysiology, including motor, auditory and somatosensory evoked potentials, is used to estimate the extent of the initial injury and predict functional recovery. The current management of brainstem haematomas remains conservative, focusing on initial close neurocritical care monitoring. Surgical treatment concepts exist, but similarly to general intracranial haemorrhage management, they continue to be controversial and have not been sufficiently investigated. This is especially the case for haematomas in the posterior fossa, as these are excluded from most current clinical trials. Existing studies were mostly carried out before the present millennium began, and limitations are evident in the adaptation of those results and recommendations to current management, with today&rsquo;s technological and diagnostic possibilities. We therefore recommend the re-evaluation of brainstem haemorrhages in the modern neurosurgical and intensive care environment

Manufacturing Feature Instances: Which Ones to Recognize?

Manufacturing features and feature-based representations have become an integral part of research on manufacturing systems, largely due to their ability to model correspondences between design information and manufacturing operations. However, several research challenges still must be addressed in order to place feature technologies into a solid scientific and mathematical framework. One challenge is the issue of alternatives in feature-based planning. Even after one has decided upon an abstract set of features to use for representing manufacturing operations, the set of feature instances used to represent a complex part is by no means unique. For a complex part, many (sometimes infinitely many) different manufacturing operations can potentially be used to manufacture various portions of the partand thus many different feature instances can be used to represent these portions of the part. Some of these feature instances will appear in useful manufacturing plans, and others will not. If the latter feature instances can be discarded at the outset, this will reduce the number of alternative manufacturing plans to be examined in order to find a useful one. Thus, what is required is a systematic means of specifying wllich feature instances are of interest. This paper addresses the issue of alternatives by introducing the notion of primary feature instances, which we contend are sufficient to generate all manufacturing plans of interest. To substantiate our argument, we describe how various instances in the primary feature set can be used to produce the desired plans. Furthermore, we discuss how this formulation overcomes computational difficulties faced by previous work, and present some complexity results for this approach in the domain of machined parts. (Also cross-referenced as UMIACS-TR-94-127