Anaesthesia & Intensive Care Medicine

Electrolyte disorders in the critically ill Publication date: Available online 6 February 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Dinusha Thanippuli Arachchige, Jason McClure Abstract Electrolyte disorders are ubiquitous in the critically ill patient, and their identification and management are vital for the patient's safe care. This article provides a guide to the aetiology, analysis and management of major electrolyte disorders in the critically ill.

The management of pulmonary embolism Publication date: Available online 6 February 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Tamara P. Banerjee, Juan Carlos. Mora Abstract Pulmonary embolism (PE) is a significant cause of hospitalization, morbidity and mortality, frequently requiring critical care services. Critically ill patients are also at increased risk of developing venous thromboembolism and acute PE. Critical care clinicians should be confident in their approach to the patient with suspected and diagnosed PE. Furthermore, the comorbid conditions in this patient group may present additional challenges both in diagnosis (e.g. safe access to radiology) and management (e.g. absolute and relative contraindications to anticoagulation/thrombolysis in critically ill patients). This brief review summarizes the contemporary evidence base regarding both diagnosis and treatment strategies and draws upon this to suggest a simple algorithm for investigation, risk stratification and management, particularly tailored to patients within a critical care setting.

Shock: causes, initial assessment, and investigations Publication date: Available online 4 February 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Gráinne Gallagher, Dashiell Gantner Abstract Shock is an umbrella term used to describe pathological processes that clinically manifest in a final common pathway of widespread cellular hypoxia. Shock develops through the interplay of disease processes and maladaptive host responses resulting in disrupted homeostasis. Central and generic components of shock include cellular hypoxia, hyperlactaemia and hypotension. Multiorgan failure usually ensues if left untreated or when management is delayed. The long-term effects include physical and psychological morbidity, as well as socioeconomic burden. As shock is a common feature of many life-threatening pathologies, its significance has been emphasized in medical education and public health campaigns globally in recent years. Key to preventing the morbidity and mortality caused by shock is early recognition, a structured approach to management, and understanding the rationale behind the different modalities of treatment. While it is beyond the scope of one article to discuss the vast subject of shock in as much depth as it deserves, this article provides an overview of shock syndromes, their context in the realms of normal physiology, and reviews the management of shock in a general context. The fundamental philosophy is that the appropriate and timely treatment of shock will save countless lives.

Ischaemic cardiogenic shock Publication date: Available online 3 February 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Carys Jones, Aidan Burrell Abstract The recognition of cardiogenic shock in the setting of myocardial ischaemia has important prognostic and therapeutic implications. Resuscitative efforts should focus on stabilizing circulatory and respiratory function, with early restoration of coronary blood flow to avoid multi-organ dysfunction and death. However, despite recent progress, the mortality rate remains high, in the order of 40–50%. This article highlights several key recent advances in the management of ischaemic cardiogenic shock, including the use of early bedside echocardiography to confirm the diagnosis, and culprit only lesion strategies of early revascularization. Furthermore, we appraise the variety of mechanical cardiac supports that are increasingly being used to assist the management of ischaemic cardiogenic shock in those cases refractory to pharmacological intervention.

Macronutrients, minerals, vitamins and energy Publication date: Available online 1 February 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Rahul Costa-Pinto, Dashiell Gantner Abstract Macronutrients comprise carbohydrates, fats and proteins and make up most of the body's soft tissue structure. Carbohydrates are organic molecules made of carbon, hydrogen and oxygen atoms. Fats are composed of carbon, hydrogen and oxygen, but the proportion of oxygen atoms to carbon and hydrogen is lower than in carbohydrates. Proteins are usually made up of more than 100 amino acids linked into chains by peptide bonds. Amino acids consist of an asymmetrical carbon atom with both an amino group (NH2) and a carboxyl group (COOH) attached. Energy used for metabolic homeostasis, thermoregulation, physical activity and normal organ function is obtained from the oxidation of these macronutrients. Micronutrients (trace minerals and vitamins) are dietary components necessary to sustain health. Most trace minerals appear to function as cofactors for a number of enzymes. Vitamins have many roles in intermediary metabolism and in the specialized metabolism of specifc organs.

Protective mechanisms of the body Publication date: Available online 1 February 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Clemente Chia, Jason McClure Abstract The skin and mucous membranes are the body's first line of defence against infection. The surface of the skin is acidic and inhibits the growth of organisms, and the openings to the various body cavities (respiratory tract, gastrointestinal tract, genitourinary tract) are lined with mucous membranes which trap bacteria and other particles. The body's outer surfaces produce chemicals which are bactericidal, skin is shed and membranes expectorate mucous in order to expel pathogens. Commensals, or non-pathogenic bacteria, further inhibit growth by competing for space and nutrients on the body's skin and mucous membrane linings. The next layer of defence is the lymphatic system, situated superficially just below the body surfaces, which drains by regional lymph nodes.

Self-assessment Publication date: Available online 27 January 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Viyayanand Nadella

Neonatal pharmacology Publication date: Available online 27 January 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Brian J. Anderson Abstract Neonatal anaesthesia dosing needs to be based on physiological characteristics of the newborn, pharmacokinetic knowledge, pharmacodynamic considerations and the adverse effects profile. Disease processes and treatments in this group are distinct from adults. Immaturity of enzyme, anatomical and physiological systems cause extensive variability of drug disposition and drug response in neonates. This is further compounded by pharmacogenomic influences. Postmenstrual age is a reasonable measure for maturation of clearance pathways. The neonatal response to drugs is altered and monitoring of effect that guides adult drug use is limited. While neuromuscular monitoring is robust, few other clinically applicable tools are available to provide pharmacodynamic effect feedback. Tools that assess depth of anaesthesia, sedation and pain in neonates have potential to improve effectiveness and safety.

Acute pain management in the neonate Publication date: Available online 25 January 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Peter Carachi, Glyn Williams Abstract Acute pain management in the neonatal period remains a challenge for the clinician. Responses to pain and analgesic intervention are developmentally influenced and cannot be directly extrapolated from the older child. Successful and safe intervention will minimize acute physiological and behavioural distress, reduce pain scores and potentially improve short- and long-term outcomes. This requires an understanding of the physiology and pharmacology in this age group alongside a multi-modal approach to treatment using both pharmacological and non-pharmacological interventions.

Anaesthesia for surgery in infancy Publication date: Available online 25 January 2020 Source: Anaesthesia & Intensive Care Medicine Author(s): Graham Knottenbelt, Amanda Dalton Abstract Specialist surgery in infancy provides challenges for paediatric anaesthetists. There is growing appreciation that the relatively higher rate of severe critical events in infants during the perioperative period requires appropriate competence, experience and resources for the safe conduct of anaesthesia. Both common (inguinal hernias and hypertrophic pyloric stenosis) and less common conditions (tracheo-oesophageal fistula, congenital diaphragmatic hernia, exomphalos, gastroschisis, and congenital lobar emphysema) require a sound understanding of the relevant pathology and the particular issues that may be encountered in these infants. In the last decade there has been a rise in the number of procedures in infancy being performed with a minimally invasive technique and this has a wide range of implications for anaesthesia.