bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetries and inequalities in the teaching of Arabic and Hebrew in the Israeli educational system
Authors: Or Iair G. , Shohamy Elana
Published: April 2016

The aim of this comparative study is to detect symmetries and asymmetries in the status of two major languages taught in Israel: Hebrew in Arabic-medium schools and Arabic in Hebrew-medium schools. The teaching of these two languages offers a unique case of language education policy where categories of ideology, policy, curriculum, methods, and assessment intersect. For Arabs, Hebrew is perceived as a major tool for upward mobility, but findings show they are alienated by a curriculum embedded in the hegemonic culture and ideology, with which they can hardly identify. For Jews, Arabic is a language of low prestige, and their motivation is hindered by a curriculum which focuses mostly on formal language and security needs, and not on communicative, interactive skills. Concluding the paper, we propose an outline for the creation of alternative teaching environments that defy existing power structures and reinvent inclusive ecologies for the learning of both languages.
Second Multiflow Summer School on Turbulence
Authors: Jiménez Javier
Published: April 2016

Multiflow is a research program, funded by the European Research Council, whose
goal is to improve our understanding of the multiscale dynamics of turbulence in fluids.
Its second Summer School on Turbulence took place at the School of Aeronautics of the
Technical University of Madrid from May 25 to June 26, 2015, with the goal of providing
a meeting place for theoreticians, experimentalists and simulators, in which to develop
and test new ideas on turbulence physics and structure. Around forty, mostly young,
participants from twenty international groups met for five weeks of collaborative work,
primarily using the computational data archived in the receiving institution but, in many
cases, also contributing their own. Although the format included a few invited formal
seminars and periodic plenary meetings, most of the work took place in small groups
that, in many cases, changed their composition during the workshop. The papers in these
proceedings reflect the results of the work of these groups which, in many cases, later
continued in the form of new collaborations.
Making progress on bycatch avoidance in the ocean salmon fishery using a transdisciplinary approach
Authors: Otto Saskia A. , Simons Sarah , Stoll Joshua S. , Lawson Peter
Published: April 2016

Transdisciplinary research that crosses disciplinary boundaries and includes stakeholder collaboration is increasingly being used to address pressing and complex socio-ecological challenges in the Anthropocene. In fisheries, we see transdisciplinary approaches being employed to address a range of challenges, including bycatch where fine-scale data are collected by fishers to help advance spatial approaches in which fishing effort is shifted away from bycatch hotspots. However, the spatio-temporal overlap of morphologically undistinguishable fish stocks, some of which are depleted, is a major concern for some fisheries, including the Pacific Northwest troll Chinook salmon (Oncorhynchus tshawytscha) fishery. In this study, we develop and evaluate a transdisciplinary approach to avoid bycatch in the commercial Chinook salmon troll fishery off northern and central Oregon. Based on a unique genetic dataset collected by fishers, fine-scale patterns of stock distribution and spatial stock overlap were assessed. Two hotspots of weak Klamath stock in the study region were identified and related to bathymetry. Results were then fed into a simple bioeconomic model to evaluate costs and benefits of reallocating effort under two scenarios of allowable catch of a weak stock (Klamath). The scenarios demonstrate that effort reallocation could lead to a reduction in Klamath catch as well as to increases in net profit, but outcomes depend on the distance from the fleets' home port to the new fishing area. The output of the model at its current stage should be regarded strategically, providing a qualitative understanding of the types of best fleet strategies. Despite some challenges in transdisciplinarity discussed in this study and the present limitations to incorporate fine-scale changes of Chinook salmon stock distributions in management regulations, we contend that this approach to research has the potential to lead to improved management outcomes.
T-cell adoptive immunotherapy using tumor-infiltrating T cells and genetically engineered TCR-T cells
Authors: Ikeda Hiroaki
Published: April 2016

Immunotherapy has received the expectation that it should contribute to the therapy of cancer patients for >100 years. At long last, recent clinical trials of immunotherapy with immune checkpoint inhibitors and adoptive cell therapy with genetically engineered T cells have reported their remarkable efficacies. Nowadays, it is expected that T-cell adoptive immunotherapy can not only control tumor progression but even cure cancer in some patients. Conversely, severe adverse events associated with efficacy have frequently been reported in clinical trials, suggesting that the assessment and control of safety will be indispensable in the future development of the therapy. New approaches in T-cell adoptive immunotherapy such as reduction of adverse events, targeting of new antigens or utilization of allogeneic cells will open a new gate for less harmful and more effective immunological treatment of cancer patients.
Neuroimaging in Multiple Sclerosis
Authors: Esch Megan , Sicotte Nancy L.
Published: April 2016

Magnetic resonance imaging (MRI) of the brain and spinal cord plays an integral role in establishing the diagnosis of multiple sclerosis (MS). The use of MRI leads to earlier recognition of MS, allowing for earlier treatment initiation and more efficient monitoring of disease treatment and progress. This chapter outlines conventional MRI imaging sequences that are used to evaluate MS white matter lesions in the central nervous system. It also addresses the incorporation of new imaging techniques that have increased understanding of clinically definite MS, its variants, and how various diseases can mimic traditional MS. Finally, it examines novel imaging protocols that have been implemented in MS research, which have elucidated radiographic and pathophysiologic nuances and involvement of deeper central nervous system structures and tracts that play a role in MS progression.
Temporal and Clinical Course of Multiple Sclerosis
Authors: Grazioli Erica , Kolb Channa , Weinstock-Guttman Bianca
Published: April 2016

The temporal and clinical course of multiple sclerosis is heterogeneous, varying among patients as well as over time in the same individual. Greater specificity in describing disease classification and course is important for conduct of clinical trials as well as prognosis for individual patients. This chapter reviews the results of recent consensus panels that have further defined the relapsing and progressive forms of multiple sclerosis through clarification of clinical relapse, subclinical relapse, active disease, and progressive disease. Clinical characteristics, conventional and nonconventional magnetic resonance imaging metrics, and immunologic and genetic biomarkers that can be used to predict disease severity and course are also discussed.
Disorders of Mobility in Multiple Sclerosis
Authors: Campea Scott , Haselkorn Jodie K.
Published: April 2016

Multiple sclerosis almost invariably affects a person’s ability to ambulate. Weakness, discoordination, spasticity, and decreased sensation may all directly contribute to impaired mobility. Multiple strategies can be used to enhance a person’s, mobility, including exercise, medications, orthotics, wheelchairs, and functional electrical stimulation. Complications of impaired mobility include skin breakdown, osteoporosis, and contractures.
Gender and Reproductive Issues in Multiple Sclerosis
Authors: Voskuhl Rhonda , Giesser Barbara S.
Published: April 2016

This chapter covers the interactions between the immune system and the reproductive system in persons with multiple sclerosis (MS). It includes detailed discussions of the immunomodulatory effects of sex hormones and sex chromosomes as they are involved in the pathophysiology of MS. Clinical effects of different hormonal states, such as pregnancy and menopause, in persons with MS are examined. Management of pregnancy in women with MS is outlined. Information on the U.S. Food and Drug Administration pregnancy category ratings for common symptom management and disease modifying therapies is provided.
Legal Planning Issues
Authors: Cooper Laura D.
Published: April 2016

As is the case with any chronic illness, multiple sclerosis can have dramatic financial and psychosocial consequences for affected individuals and their families. This chapter provides detailed information on regulations regarding the Americans with Disabilities Act and disability insurance. It outlines a practical approach to financial planning for persons with multiple sclerosis. Health care policy changes related to the Affordable Care Act are also reviewed. A section on advanced health directives is included.
Staffing models in the ICU
Authors: Buchman Tim , Sterling Michael
Published: April 2016

Three decades ago a critical care provider surplus was forecast. Projections changed at the turn of the century when the Committee on Manpower of Pulmonary and Critical Care Societies (COMPACCS) report was issued. Demographers, statisticians, and clinicians used population, patient, hospital, and provider data to forecast that the supply for critical care physicians would not keep pace with demand, and that the shortfall would be around 22% by 2020, climbing to 35% by 2030. In 2006, the Health Resources and Services Administration (HRSA) similarly forecast a significant shortage of intensivists by 2020. All signs suggest that the COMPACCS prediction is correct. This chapter describes and discusses three novel strategies by which intensivist expertise can be leveraged to provide care for a larger group of critically-ill patients. The three strategies include the use of hospitalists, engagement of affiliate providers (nurse practitioners and physician assistants with advanced critical care competencies), and investment in tele- ICU services. These strategies are complementary and can be combined to provide models tailored to local needs and resources.
Management of pandemic critical illness
Authors: Fowler Robert , Duggal Abhijit
Published: April 2016

Adequate and appropriate provision of critical care services during pandemics may dramatically alter vital outcomes of patients who develop acute respiratory distress syndrome and critical illness. Specific anti-viral therapy, antibiotics directed towards probable secondary infections, supportive ventilation and oxygenation, and adherence to multisystem critical care ‘best practices’ can prevent substantial mortality and morbidity, and lessen the pandemic’s impact on global health. However, severe acute respiratory syndrome and the 2009 H1N1 pandemic also highlighted the limited capacity for increased provision of critical care, even in well-resourced settings, and the potential for dramatic differences in mortality in under-resourced settings. Pandemic preparedness hinges on the development of appropriately-trained staff with well-defined roles, and the ability to manage surge in the number of patients. A rigorous infection control programme, and triage protocols based on equitable distribution of resources and ethical principles of justice, beneficence and non-maleficence. Research preparedness, with approved protocols, electronic case report forms and harmonized clinical trials is necessary.
Clinical skills in critical care
Authors: Nimmo Graham , Shippey Ben
Published: April 2016

This chapter provides a framework for the learning and teaching of both technical and non-technical skills. There is a deliberate weighting towards decision-making and behavioural skills because of their prevalence in practice, the importance of delivering them reliably, and the need to increase their profile in our wards, classrooms, skills centres, and curricula. The practice of clinical intensive care requires the application of a huge range of clinical skills each of which has its own knowledge base and where each necessitates the acquisition of a technique. It is necessary to consider the application of these skills in the ‘messy’, sometimes chaotic environment of the intensive care unit where multiple critically-ill patients are simultaneously requiring individual input and at the same time relatives require support, learners need teaching, and time and attention are invested in the crucial processes of audit, quality improvement and research.
Costs and cost-effectiveness in critical care
Authors: Wallace David J. , Angus Derek C.
Published: April 2016

Critical care accounts for a large and growing part of national health expenditures. Cost-effectiveness analyses are one way to identify therapies that maximize society’s return on investment. This chapter provides a broad overview of four cost study designs—cost-minimization, cost-benefit, cost-effectiveness, and cost-utility. Cost -effectiveness analysis allows the costs and benefits of different therapies to be directly compared. Within a constrained budget, cost-effectiveness analysis can identify the optimal therapies for funding. Policy informed by cost effectiveness should improve public health. The reader is introduced to the concepts of cost perspective, included costs and cost discounting. We conclude by describing policy implications of cost effectiveness evaluations and highlight their relevance to the Patient-Centered Outcomes Research Institute.
Informed consent in the ICU
Authors: Silverman Henry J.
Published: April 2016

The doctrine of informed consent is an important concept in medical care, but presents challenges in the critical care setting, where patients may have diminished capacity to provide their own informed consent. The elements of informed consent include adequate disclosure of information, cognitive capacity of individuals to make decisions, and the voluntary nature of such decisions. Currently, there are no universally accepted procedures regarding capacity assessment, especially in critically-ill patients. Such assessments remain subjective, but this chapter provides some guidelines on the subjective assessment of such capacity. When it is determined that patient lacks decision making capacity to provide consent, several mechanisms exist by which their autonomy can still be respected, including following any existing advance directives or family members or friends’ moral authority to make decisions for patients, based on either the substituted standard or the best-interests standard. Informed consent issues in the emergency clinical situations and in the context of research are also discussed.
The role and limitations of scoring systems
Authors: Wunsch Hannah , Kramer Andrew A.
Published: April 2016

Scoring systems for critically-ill patients provide a measure of the severity of illness of patients admitted to intensive care units (ICUs). They are primarily based on patient characteristics, physiological derangement, and/or clinical assessments. Severity scores themselves allow for risk-adjusting outcomes, but they can also be used to provide a prediction of the overall risk of death, length of stay, or other outcome for critically ill patients. This allows for comparison of outcomes between different cohorts of patients or between observed and predicted ICU performance. There are a number of general ICU scoring systems that are in use. All scoring systems have limitations. Future scoring systems may include prediction of longer-term outcomes, and assimilation of granular data temporally and at the molecular level that could result in more personalized severity scores to help guide individual care decisions.
Organ failure scoring
Authors: Moreno Rui
Published: April 2016

The general outcome prediction models were not, by design, developed to track individual patients. They provided an indication of death risks for groups of ICU patients. Hence, investigators created organ failure scores. Instruments, such as Sequential Organ Failure Assessment (SOFA), Multiple Organ Dysfunction Score, or Logistic Organ Dysfunction Score are designed to evaluate separately the six most important organ systems in critically-ill patients sequentially, taken on a daily basis. Easy to perform, designed to be done at bedside, they do not forecast ICU or hospital mortality (apart from the SOFA score), but are very useful in describing the patient and his response to therapy.
Oxygen in critical illness
Authors: Fullerton James N. , Singer Mervyn
Published: April 2016

Oxygen therapy is primarily administered to alleviate arterial hypoxaemia and tissue hypoxia, and to facilitate aerobic cellular respiration. Hypoxaemia (PaO2 < 8 kPa [60 mmHg], SaO2 <92%) is associated with end-organ damage and adverse clinical outcomes, serving as a proxy measure for reduced intracellular PO2. Increasing the fraction of inspired oxygen should form part of an overall strategy to maximize tissue oxygen delivery. Permissive hypoxaemia represents a valid treatment strategy in a selected patient cohort. Oxygen is a drug and oxygen therapy is not benign, and oxygen administration at high, sustained doses (FiO2 >0.5, >12 hours) may cause oxygen toxicity. Observational studies in both mechanically-ventilated patients and survivors of non-traumatic cardiac arrest indicate an independent association between increasing hyperoxaemia and mortality. Oxygen therapy may additionally precipitate hypercapnic ventilatory failure in those at risk and oxygen should be administered to achieve a prescribed target SaO2 or PaO2 range, via adjustment of dose and delivery device. If no monitoring is available, hypoxaemia should be avoided by giving high-flow oxygen to achieve a FiO2 of near 1.0 with subsequent titration once oxygenation status is established.
Vasodilators in critical illness
Authors: Groeneveld A. B. J. , Lima Alexandre
Published: April 2016

Vasodilators are commonly used in the intensive care unit (ICU) to control arterial blood pressure, unload the left or the right heart, control pulmonary artery pressure, and improve microcirculatory blood flow. Vasodilator refers to drugs acting directly on the smooth muscles of peripheral vessel walls and drugs are usually classified based on their mechanism (acting directly or indirectly) or site of action (arterial or venous vasodilator). Drugs that have a predominant effect on resistance vessels are arterial dilators and drugs that primarily affect venous capacitance vessels are venous dilators. Drugs that interfere with sympathetic nervous system, block renin-angiotensin system, phosphodiesterase inhibitors, and nitrates are some examples of drugs with indirect effect. Vasodilator drugs play a major therapeutic role in hypertensive emergencies, primary and secondary pulmonary hypertension, acute left heart, and circulatory shock. This review discusses the main types of vasodilators drugs commonly used in the ICU.
Muscle relaxants in critical illness
Authors: Pollard Brian J.
Published: April 2016

The place of neuromuscular blocking agents in the intensive care unit (ICU) has changed markedly over the last 20 years. Originally regarded as a mainstay of the process of ‘sedation’, they are now only used for specific indications. The principal disadvantage is probably the difficulty in neurological assessment when a muscle relaxant is used coupled with the increased risk of awareness, because inadequate sedation will be masked. Of the available agents, the intermediate acting ones are the most popular. The degree of relaxation can be readily controlled and they have few side effects. In the presence of renal and/or hepatic disease atracurium or cisatracurium are preferred. Succinylcholine is only used for securing the airway due to its very rapid onset of action. Rocuronium given in a higher dose also possesses a rapid onset in situations when succinylcholine might be contraindicated. When using a muscle relaxant, its effect should always be monitored with a simple train of four pattern of stimulation from a hand-held nerve stimulator. This will ensure that an adequate and not excessive block is secured. If a more rapid reversal is required then a dose of neostigmine with glycopyrrolate may be used. Alternatively, if rocuronium is the relaxant in use then the new agent sugammadex is effective.
Anticoagulants and antithrombotics in critical illness
Authors: McDonald Vickie , Scully Marie
Published: April 2016

Coagulation is best thought of using the cell-based model of coagulation. Patients commenced on heparin therapy should have their platelet count monitored early because of the risk of heparin-induced thrombocytopenia, which can occur on any type or dose of heparin. Emergency reversal of warfarin should be with prothrombin complex concentrate (containing factors II, VII, IX, and X) and not fresh frozen plasma. New oral anticoagulants have the advantage of predictable pharmacokinetics and do not require routine monitoring, but optimal reversal strategies for these agents are not clear. Thrombolytic agents lead to variable degrees of systemic lysis, which may cause haemorrhage, including intracerebral haemorrhage
Antimicrobial drugs in critical illness
Authors: Wilson A. P. R. , Panesar Preet
Published: April 2016

The pharmacokinetics of antimicrobials are altered in critically-ill patients, particularly in the presence of renal or hepatic failure. Maintaining a choice or diversity of antibiotics is important due to the emergence of resistance. Antibiotic use should also be kept to the minimum and local protocols need to be established. For community-acquired infection, co-amoxiclav or a parenteral cephalosporin can be used, while for hospital-acquired infection, piperacillin/tazobactam, ciprofloxacin, or ceftazidime are recommended. For suspected vascular catheter infection or methicillin-resistant Staphylococcus aureus (MRSA) infection, teicoplanin or vancomycin should be used, with meropenem or imipenem reserved for second line treatment. Prophylactic antibiotics should not be continued once a surgical patient has returned from the theatre. Patients with febrile neutropenia receive piptazobactam, meropenem, ceftazidime or ciprofloxacin and a glycopeptide. Antifungals, usually caspofungin or liposomal amphotericin, are used if fungal infection is suspected, especially after failed antibacterial treatment. Cephalosporin use has declined as they have been linked with emergence of MRSA and Clostridium difficile. However, this reflects overuse and they still have a place as part of a diverse choice of antibiotics. Vancomycin and teicoplanin use has increased greatly in order to treat MRSA and line infections, but resistance remains unusual. Carbapenem use has increased rapidly with the emergence of extended spectrum beta-lactamase producing Gram-negative bacteria.
Steroids in critical illness
Authors: Keh Didier
Published: April 2016

The benefit of prolonged application of moderate-dose corticosteroids in systemic inflammatory diseases remains controversial. In critical illness, the endogenous cortisol effect may become insufficient due to adrenal dysfunction and corticosteroid resistance to counterbalance an exaggerated and protracted inflammatory response, which has been termed ‘critical illness-related corticosteroid insufficiency’ (CIRCI). There is evidence that moderate-dose hydrocortisone (200–300 mg/day) significantly fastens shock reversal in patients with septic shock, but may improve survival probably only in patients with high risk of death. Thus, therapy should be considered only in refractory shock with poor response to fluid administration and vasopressor therapy. The indication should be based on clinical judgement and not on cortisol measurement. The application prolonged of moderate-dose methylprednisolone (1 mg/kg/day) was found to be most effective in early acute respiratory distress syndrome, and associated with improved lung function, reduction of mechanical ventilation, and faster discharge from the ICU, but a survival benefit was found only in pooled data, including cohort studies. A continuous infusion and weaning of corticosteroids may be preferable to bolus applications and abrupt withdrawal to avoid side effects such as rebound of inflammation and shock, glucose variability, or respiratory failure. There is currently no evidence that prolonged application of moderate-dose corticosteroids increase the risk of secondary infections or muscle weakness, but infection surveillance should be implemented and combination with muscle relaxants be avoided.
Diuretics in critical illness
Authors: Ostermann Marlies , Wan Ruth Y. Y.
Published: April 2016

Fluid overload and chronic hypertension are the most common indications for diuretics. The diuretic response varies between different types and depends on underlying renal function. In patients with congestive heart failure, diuretics appear to reduce the risk of death and worsening heart failure compared with placebo, but their use in acute decompensated heart failure is questionable. Diuretics are also widely used in chronic kidney disease to prevent or control fluid overload, and treat hypertension. In acute kidney injury, there is no evidence that they improve renal function, speed up recovery, or change mortality. In patients with chronic liver disease and large volume ascites, paracentesis is more effective and associated with fewer adverse events than diuretic therapy, but maintenance treatment with diuretics is indicated to prevent recurrence of ascites. Mannitol has a role in liver patients with cerebral oedema and normal renal function. The use of diuretics in rhabdomyolysis is controversial and restricted to patients who are not fluid deplete. In conditions associated with resistant oedema (chronic kidney disease, congestive heart failure, chronic liver disease), combinations of diuretics with different modes of action may be necessary. Diuresis is easier to achieve with a continuous furosemide infusion compared with intermittent boluses, but there is no evidence of better outcomes. The role of combination therapy with albumin in patients with fluid overload and severe hypoalbuminaemia is uncertain with conflicting data.
Defibrillation and pacing during cardiac arrest
Authors: Deakin Charles D.
Published: April 2016

Defibrillation is the passage of electrical current across the myocardium to allow synchronized repolarisation and return of a perfusing rhythm. It is now an established intervention for patients in shockable rhythms during cardiac arrest and is administered every 2 minutes during resuscitation until return of spontaneous circulation. Modern biphasic waveforms are more effective than older monophasic waveforms, achieving first shock success rate of approximately 90%. For ventricular fibrillation in adults, the initial shock should be delivered at 150 J, and if further shocks are required, escalating energy is probably more effective than a fixed energy strategy. All paediatric shocks should be delivered at 4 J/kg. Although it is important to stand clear of the patient when the shock is delivered, defibrillation should be administered with minimal interruption to resuscitation, ideally resulting in a pause to chest compressions of no more than 5 seconds. External pacing may be life-saving in patients refractory to pharmacological support of bradyarrhythmias, but is ineffective for asystole.
Ethical and end-of-life issues after cardiac arrest
Authors: Benson Carolyn , Young G. Bryan
Published: April 2016

Many survivors of cardiac arrest, especially out-of-hospital cardiac arrest, suffer varying degrees of anoxic-ischaemic brain injury. Accurate neurological prognostication to determine which patients will have poor neurological outcome is important to guide appropriate medical care and advise surrogate decision makers. Accurate prognostication generally requires the presence of two or more negative prognostic indicators, especially following treatment with therapeutic hypothermia. Medical care should be directed at achieving survival that the patient would consider acceptable. Poor quality survival is generally defined as severe disability with full dependency, minimally-conscious, or vegetative state. Discussions regarding prognosis and management of patients who remain unresponsive after resuscitation from cardiac arrest should be conducted in a professional manner and show respect for the individuals involved, their culture, and religion.
Imaging the respiratory system in the critically ill
Authors: Goodman Lawrence R.
Published: April 2016

Routine radiographs are not cost effective in the intensive care unit (ICU) setting. Most published guidelines agree that radiographs are worthwhile after insertion of tubes or catheters, and in patients receiving mechanical ventilation. Otherwise, they are required only for change in the patient’s clinical status. Picture archiving and communication systems utilize digital imaging technology. They provide superior quality images, rapid image availability at multiple sites, and fewer repeat examinations, reducing both cost and patient radiation. Disadvantages of picture archiving and communication systems include expensive equipment and personnel required to keep them functioning. The majority of chest X-ray abnormalities in the ICU are best understood by paying careful attention to the initial appearance of the X-ray in relation to the patient’s onset of symptoms and the progression of abnormalities over the next few days.
Pulmonary mechanical dysfunction in the critically ill
Authors: Lucangelo Umberto , Ferluga Massimo
Published: April 2016

In intensive care units practitioners are confronted every day with mechanically-ventilated patients and should be able to sort out from all the data available from modern ventilators to tailored patient ventilatory strategy. Real-time visualization of pressure, flow and tidal volume provide valuable information on the respiratory system, to optimize ventilatory support and avoiding complications associated with mechanical ventilation. Early determination of patient–ventilator asynchrony, air-trapping, and variation in respiratory parameters is important during mechanical ventilation. A correct evaluation of data becomes mandatory to avoid a prolonged need for ventilatory support. During dynamic hyperinflation the lungs do not have time to reach the functional residual capacity at the end of expiration, increasing the work of breathing and promoting patient-ventilator asynchrony. Expiratory capnogram provides qualitative information on the waveform patterns associated with mechanical ventilation and quantitative estimation of expired CO2. The concept of dead space accounts for those lung areas that are ventilated but not perfused. Calculations derived from volumetric capnography are useful indicators of pulmonary embolism. Moreover, alveolar dead space is increased in acute lung injury and its value decreased in case of positive end-expiratory pressure (PEEP)-induced recruitment, whereas PEEP-induced overdistension tends to increment alveolar dead space.
Pressure-controlled mechanical ventilation
Authors: Muders Thomas , Putensen Christian
Published: April 2016

Beside reduction in tidal volume limiting peak airway pressure minimizes the risk for ventilator-associated-lung-injury in patients with acute respiratory distress syndrome. Pressure-controlled, time-cycled ventilation (PCV) enables the physician to keep airway pressures under strict limits by presetting inspiratory and expiratory pressures, and cycle times. PCV results in a square-waved airway pressure and a decelerating inspiratory gas flow holding the alveoli inflated for the preset time. Preset pressures and cycle times, and respiratory system mechanics affect alveolar and intrinsic positive end-expiratory (PEEPi) pressures, tidal volume, total minute, and alveolar ventilation. When compared with flow-controlled, time-cycled (‘volume-controlled’) ventilation, PCV results in reduced peak airway pressures, but higher mean airway. Homogeneity of regional peak alveolar pressure distribution within the lung is improved. However, no consistent data exist, showing PCV to improve patient outcome. During inverse ratio ventilation (IRV) elongation of inspiratory time increases mean airway pressure and enables full lung inflation, whereas shortening expiratory time causes incomplete lung emptying and increased PEEPi. Both mechanisms increase mean alveolar and transpulmonary pressures, and may thereby improve lung recruitment and gas exchange. However, when compared with conventional mechanical ventilation using an increased external PEEP to reach the same magnitude of total PEEP as that produced intrinsically by IRV, IRV has no advantage. Airway pressure release ventilation (APRV) provides a PCV-like squared pressure pattern by time-cycled switches between two continuous positive airway pressure levels, while allowing unrestricted spontaneous breathing in any ventilatory phase. Maintaining spontaneous breathing with APRV is associated with recruitment and improved ventilation of dependent lung areas, improved ventilation-perfusion matching, cardiac output, oxygenation, and oxygen delivery, whereas need for sedation, vasopressors, and inotropic agents and duration of ventilator support decreases.
Therapeutic approach to bronchospasm and asthma
Authors: Sampson Brett G. , Bersten Andrew D.
Published: April 2016

The optimal management of bronchospasm and acute asthma is reliant upon confirmation of the diagnosis of asthma, detection of life-threatening complications, recognition of β‎2 agonist toxicity, and exclusion of important asthma mimics (such as vocal cord dysfunction and left ventricular failure). β‎2 agonists, anticholinergics, and corticosteroids are the mainstay of treatment. β‎2 agonists should be preferentially administered by metered dose inhaler via a spacer, and corticosteroids by the oral route, reserving nebulized (and intravenous) salbutamol, as well as intravenous hydrocortisone, for situations when these routes are not possible. A single intravenous dose of magnesium may be of benefit in severe asthma, but repeat dosing is likely to cause serious side effects. Parenteral administration of adrenaline may prevent the need for intubation in the patient in extremis. Aminophylline has an unfavourable side effect profile and has not been shown to offer additional benefit in adults. However, it does have a role in paediatric asthma. Unproven medical therapies with potential benefit include ketamine, heliox, inhalational anaesthetics, and leukotriene antagonists. The need for ventilatory support is usually preceded by worsening dynamic hyperinflation, exhaustion, hypoxia, reduced conscious state, or a combination of these. While non-invasive ventilation may have a temporizing role to allow time for response to medical therapy, there is insufficient evidence for its use, and should not delay invasive ventilation. If invasive ventilation is indicated, a strategy of hypoventilation and permissive hypercapnoea, minimizes barotrauma and dynamic hyperinflation. Extracorporeal support may have a role as a rescue therapy.
Lung recruitment techniques in the ICU
Authors: Kiss Thomas , Pelosi Paolo
Published: April 2016

Lung recruitment manoeuvres (RMs) have been suggested as a means of homogenizing the lung structure and distribution of the mechanical stress across the lungs. Such effects can be achieved provided enough pressure is applied for enough time at the airways, and maintained if adequate levels of positive end-expiratory pressure (PEEP) are used. When RMs effectively open atelectatic tissue, shear stress, and cyclic collapse/reopening are importantly reduced. The lung response to RMs is mainly determined by cause and severity of lung injury, and the position of the lungs with respect to the gravity gradient. RMs can be performed in several different ways, the most relevant RMs in terms of clinical applicability are sustained inflation manoeuvres, high pressure controlled ventilation, incremental PEEP, and intermittent sighs.
Arterial and venous cannulation in the ICU
Authors: O’Leary Ronan , Bodenham Andrew R.
Published: April 2016

Despite being almost ubiquitous within the critically- ill population, vascular access remains a frequent cause of iatrogenic injury, manifested as both procedural complications and later events, such as infection and thrombosis. Untoward events are minimized by expert tuition and meticulous practical technique. Consensus guidelines on training in vascular access are discussed. Vascular access, particularly central catheterization, should not be undertaken lightly. Can a patient be managed without vascular access or can the number of vascular access devices be rationalized? Other routes for drug and fluid administration exist, particularly enterally during the recovery phase. This chapter covers vascular access during critical illness and discusses the development of more advanced techniques.
Blood pressure monitoring in the ICU
Authors: Romagnoli Stefano , Zagli Giovanni
Published: April 2016

Two major systems are available for measuring blood pressure (BP)—the indirect cuff method and direct arterial cannulation. In critically-ill patients admitted to the intensive care unit, the invasive blood pressure is the ‘gold standard’ as a tight control of BP values, and its change over time is important for choosing therapies and drugs titration. Since artefacts due to the inappropriate dynamic responses of the fluid-filled monitoring systems may lead to clinically relevant differences between actual and displayed pressure values, before considering the BP value shown as reliable, the critical care giver should carefully evaluate the presence/absence of artefacts (over- or under-damping/resonance). After the arterial pressure waveform quality has been verified, the observation of each component of the arterial wave (systolic upstroke, peak, systolic decline, small pulse of reflected pressure waves, dicrotic notch) may provide a number of useful haemodynamic information. In fact, changes in the arterial pulse contour are due the interaction between the heart beat and the whole vascular properties. Vasoconstriction, vasodilatation, shock states (cardiogenic, hypovolaemic, distributive, obstructive), valve diseases (aortic stenosis, aortic regurgitation), ventricular dysfunction, cardiac tamponade are associated with particular arterial waveform characteristics that may suggest to the physician underlying condition that could be necessary to investigate properly. Finally, the effects of positive-pressure mechanical ventilation on heart–lung interaction, may suggest the existence of an absolute or relative hypovolaemia by means of the so-called dynamic indices of fluid responsiveness.
Mixed and central venous oxygen saturation monitoring in the ICU
Authors: Bloos Frank , Reinhart Konrad
Published: April 2016

Haemodynamic resuscitation should target goals that reflect the tissue oxygen needs of an individual patient. Venous oximetry may be such a tool. Oxygen saturation of blood in the pulmonary artery contains venous blood from the whole body and is referred to as mixed oxygen saturation (SvO2). Measurement of oxygen saturation in blood obtained from a central venous catheter is referred to as central venous oxygen saturation (ScvO2). Both values are not identical since a catheter placed into the superior vena cava only represents venous blood draining the upper body. While it is not possible, in the clinical setting, to predict SvO2 from ScvO2, changes in SvO2 are adequately mirrored by changes in ScvO2. Post-operative patients and patients admitted to intensive care with a low ScvO2 show a higher morbidity and mortality. Early goal-directed therapy (EGDT) combines several haemodynamic goals into a treatment algorithm, including a ScvO2 target. However, recent studies do not support the systematic use of this protocolized approach. A normal value of SvO2 or ScvO2 saturation does not always exclude tissue hypoxia, since it is not possible to identify an inadequate oxygen supply in single organs. A further limitation of this technique is that organ dysfunction can progress, or serum lactate increases, despite normal or even increased venous oximetry values.
Causes and diagnosis of chest pain
Authors: Patterson Caroline , Bell Derek
Published: April 2016

Differentiating life-threatening from benign causes of chest pain in the critical care setting is a challenge when the symptoms and signs overlap, and patients are unable to communicate fully. A high index of suspicion is required for occult disease. Once the clinician has ensured the patient is haemodynamically stable, it is imperative to rule out myocardial infarction in the first instance. Where possible, a thorough history and a full examination should be undertaken. Electrocardiogram, chest X-ray, and routine observations are often diagnostic. Targeted investigation such as computed tomography, or transthoracic or transoesophageal ultrasonography may be required to confirm these diagnoses. Timely intervention optimizes survival benefit. Treatment may be necessary prior to confirmation of diagnosis, based on high clinical suspicion and risk scoring. Other causes of chest pain should be considered once the immediately life-threatening conditions are excluded.
Diagnosis and management of shock in the ICU
Authors: Spevetz Antoinette , Parrillo Joseph E.
Published: April 2016

Sepsis is triggered by an infection and treatment of sepsis requires timely identification of the patient, and rapid treatment with antibiotics, source control, and fluids. In the absence of a true biomarker for sepsis, the clinician needs to recognize which patients are at risk, as well as the common signs and symptoms of infection. The site of infection, the patient’s phenotype, and the location of the patient will help drive decisions about initial antibiotic therapy. Patients with sepsis should be treated to ensure adequate cardiac output and organ perfusion, which usually requires infusion of intravenous fluids. Crystalloid fluids are most frequently infused, and patients will often require large doses in the first 6–24 hours of treatment. In addition to haemodynamic and fluid support, some patients require infection source control. Many sepsis patients require additional supportive therapy with vasoactive agents, mechanical ventilation, renal replacement therapy, and nutritional therapy. The use of these supportive therapies allows for a patients host defence system to work in conjunction with antibiotics to fight off the infection. When using these supportive therapies, the clinician should attempt to minimize the complications of the therapies and the causative infection. Once a patient starts to clinically improve, it is essential that therapies that are no longer necessary are withdrawn. Patients who do not respond to initial therapy should be evaluated for either resistant organisms, persistent sources, or alternate diagnoses.
Pathophysiology and causes of cardiac failure
Authors: Mebazaa Alexandre , Singer Mervyn
Published: April 2016

Organ congestion upstream of the dysfunctional left and/or right ventricle, with preserved stroke volume, is the most frequkeywordent feature of myocardial failure.Clinical manifestations do not necessarily correlate with the degree of left ventricular systolic dysfunction (i.e. left ventricular ejection fraction).Systolic and/or diastolic dysfunction may be present, with systolic dysfunction usually predominating.Pulmonary oedema is related to left ventricular diastolic dysfunction. Compensatory mechanisms (within the heart and/or periphery) may prove paradoxically disadvantageous on ventricular stroke work and stroke volume.
Pathophysiology and causes of pulmonary embolism
Authors: Singer Mervyn
Published: April 2016

Pulmonary embolus is predominantly due to thrombus breaking off from deep veins or from within the right heart, lodging within large or small vessels within the pulmonary vasculature, causing a variable degree of clinical features ranging from asymptomatic through to shock and cardiac arrest. Non-thrombotic causes include air or fat embolism. Outcome is predicated by the degree of right ventricular dysfunction. There are multiple risk factors including surgery, arrhythmias, prolonged immobility, venous stasis, pregnancy and an underlying pro-thrombotic tendency, either congenital or acquired. Numerous risk stratification scores have been developed derived from clinical features, imaging findings and biochemical markers of right ventricular strain and myocardial damage.
Imaging the abdomen in the critically ill
Authors: Niazi Imran Khalid , Ramachandran Navin
Published: April 2016

Abdominal evaluation of the critically-ill patient is challenging. The patient may have a vague presentation, sometimes with a poor clinical history, few localizing signs, multiple co-morbidities and multi-organ involvement. Often the patient will require resuscitation prior to diagnostic work-up, and support devices such as mechanical ventilators and haemofilters may hamper assessment. Such unreliability of clinical indicators and the myriad of abdominal pathologies in a critically-ill patient may lead to diagnostic uncertainty with consequent delays in treatment. These challenges make imaging one of the most critical steps in the management of such patients. The optimal imaging pathway should be sensitive, specific, and minimize delay in therapy, but should also account for the patient’s clinical state and overall radiation dose. The modalities that have a role in abdominal evaluation of the critically ill are covered in this chapter.
Diagnosis and management of lower gastrointestinal haemorrhage in the critically ill
Authors: Kobayashi Leslie M. , Coimbra Raul
Published: April 2016

Lower gastrointestinal bleeding (LGIB) is a common cause of anaemia, and can be a significant cause of bleeding and hypovolaemic shock. Initial treatment should always begin with protection of the airway, fluid resuscitation, and restoration of haemodynamic stability. Early colonoscopy should be utilized for all patients with brisk bleeding and elective colonoscopy for those who are stable. An alternative to endoscopy is angiography. Surgery is reserved for patients recalcitrant to endoscopy and/or angiography, or those with poor response to resuscitation. Patients with very slow haemorrhage or with occult sources of bleeding can be diagnosed with enteroscopy and CT scanning. CT is well tolerated, rapid, and repeatable, but enteroscopy has the benefit of being potentially therapeutic. Most cases of LGIB resolve spontaneously and those that do not tend to respond well to endoscopic treatment.
Pathophysiology, diagnosis, and assessment of acute or chronic hepatic failure
Authors: O’Brien Alastair
Published: April 2016

Cirrhosis is an increasing problem and prognosis following intensive care unit admission is poor. Acute on chronic liver failure (ACLF) is a separate entity to cirrhosis with organ failure at the core of this syndrome. Infection and the associated systemic inflammatory responses are the most important precipitants of ACLF. Clinical assessment should follow the standard airway breathing circulation disability exposure approach to the critically-ill patient.