Anaesthesia & intensive care medicine - Current Issue

Pain is a sensory and emotional experience that is personal and unique to an individual. Nociception is different from pain and considers the neural process of encoding and processing noxious stimuli. Anatomically noxious stimuli are transduced by nociceptors to an electrical signal carried by first-order neurons to the dorsal horn of the spinal cord. From the spinal cord second-order neurons project in tracts to the thalamus, where third-order neurons continue to higher cerebral centres. There is no known primary pain processing centre in the brain, instead multiple different areas activate and interact in response to noxious stimuli.

Pain is the most common reason for patients to see a doctor. Socio-economic issues including unemployment and difficulty accessing education are common in such patients. Pain is the third leading cause for absence from work. Patients frequently seek support from their multidisciplinary pain team for welfare support and staying in or returning to employment or education. Pain physicians perform a range of intervention procedures and need to have a clear grasp of the law of consent. They are also called on to give expert evidence in personal injury and medical negligence claims where claimants have been left with chronic pain.

Chronic pain is a major cause of disability. Outpatient pain management services take a multidisciplinary approach based on a bio-psychosocial framework, providing assessment and management of patients who suffer from chronic pain. The emphasis is on education and promotion of self-management. Appropriate facilities, management and cohesive working is essential to provide evidence-based effective pain management.

Early identification and anaesthetic assessment of high-risk patients in pregnancy is important and best delivered through a formal assessment clinic. It provides the opportunity to provide information, agree management plans, and carry out necessary investigations and referrals to other specialists prior to labour and delivery. Clear referral criteria and lines of communication are necessary for an effective service.

Paediatric pain is often poorly recognized and undertreated, and managing it effectively can be complex and challenging. Exposure to severe pain without adequate management in childhood can be detrimental and is associated with adverse long-term outcomes such as chronic pain, anxiety and depressive disorders later in life. A multimodal analgesic regimen is recommended, and is just one aspect of a multi-faceted approach to paediatric pain management.The aim of this review is to highlight systemic analgesic options for children, including important considerations for neonates.

Peripheral nerves blocks provide intra- and postoperative analgesia and are an important element of the multimodal approach to perioperative pain. This is particularly important in the paediatric population, where the side effects of opioids, such as respiratory depression, postoperative nausea and vomiting (PONV), and gastrointestinal motility issues, can be especially challenging. The addition of a block to the multimodal strategy allows in most situations for a significant dose reduction in opioid requirements and in some cases to a complete avoidance of opioids.

Sedation of children is often an unavoidable component of many diagnostic and therapeutic healthcare interventions in children. Traditional agents such as chloral hydrate and midazolam continue to be widely used in a safe and effective manner. However, experience with other agents has grown in recent years. This produced more options and shifted attitudes on how sedation may be defined, conceptualized and delivered. This article discusses these changes, as well as covering some of the non-pharmacological factors and issues involved.

Paediatric day case surgery is suitable for many children and procedures, offering benefits to patients, families and organizations. For day surgery units to be successful, thorough processes must be followed to ensure that patients are correctly selected and prepared, lists are organized appropriately, and resources are in place to manage day case smoothly. Techniques for anaesthesia and analgesia should be tailored to facilitate day case discharge with clear information provided to patients and families.

The placenta is an organ that connects a developing fetus to the uterine wall for the exchange of nutrients, antibodies and hormones between mother and fetus. The development of the placenta is essential for the removal of waste products, for fetal growth, development and the maintenance of a healthy pregnancy and it is an important endocrine organ.

Pre-eclampsia is a multisystem disorder associated with end-organ damage that forms part of the spectrum of hypertensive disorders of pregnancy. It occurs after 20 weeks’ gestation and contributes to significant maternal and fetal morbidity. In the UK, it was responsible for nearly 2.5% of maternal deaths in the recent maternal confidential death report. Placental growth factor-based testing and estimation of soluble fms-like tyrosine kinase 1 to placental growth factor (sFlt-1/PIGF) ratio can improve diagnostic accuracy and predict the risk of maternal complications.

Labour pain is one of the most painful experiences encountered in healthcare. Labour analgesia can be provided by neuraxial or non-neuraxial techniques. Non-neuraxial analgesia can be offered in women in whom neuraxial techniques are contraindicated or are unsuccessful. They may also be chosen as a first-line analgesia by some women. The use of patient-controlled analgesia using remifentanil is a useful alternative to an epidural and is being offered by increasing number of delivery units.

Neuraxial analgesia is the gold standard for managing pain during labour. Techniques employed to facilitate labour neuraxial analgesia include the use of an epidural catheter, the combined spinal epidural, the dural puncture epidural, and an intrathecal catheter. The adoption of these techniques for labour analgesia varies across different maternity units. Over time, numerous regimens have been developed for enhancing labour neuraxial analgesia effectiveness while minimizing maternal side effects.

Intravenous fluids are a core therapy in critical care and perioperative practice. Although most fluids that we use today are very similar to those of the mid 20th Century, our understanding of the physiology of the cardiovascular system, the microcirculation and the extravascular space has evolved considerably. In modern practice, thought should be given to the distribution of stressed and unstressed blood volume, the glycocalyx and the gelatinous interstitial matrix. All of these components change dynamically in volume depleted states.

The uterus serves the essential function of supporting the fetus throughout the duration of pregnancy until childbirth. It is anatomically divided into three main sections: the fundus, the body, and the cervix. The functioning of the uterus is primarily regulated by hormones, which induce considerable transformations during pregnancy. At the time of delivery, alterations in hormonal levels trigger cervical remodelling and uterine contractions, resulting in the expulsion of the fetus. Various medications can influence uterine activity and may be utilized to either initiate or inhibit labour.

Spinal-induced hypotension (SIH) is a common but potentially serious side effect of spinal anaesthetics during caesarean section, with potential maternal and fetal consequences. A number of non-pharmacological methods can be employed to reduce the incidence of SIH, including maternal positioning and fluids. However, these should be used in conjunction with pharmacological methods, which have been shown to be superior in reducing SIH. For many years phenylephrine has been the standard vasopressor in obstetrics, but emerging evidence indicates that there may be more appropriate pharmacological options, with a promising/recent focus on investigating noradrenaline.

Causes of childhood pain include peri-procedural, injury and disease. Systematic reviews have shown that pain can lead to anxiety, sleep disturbance, and have deleterious effects on daily life.Experienced pain is influenced by biological, psychological and social factors. Pain assessment in children is particularly challenging due to the wide variation in physiological responses, communication abilities and developmental stages of this group of patients. For example, their limited verbal repertoire can lead to an under-recognition of pain as compared to adults who may be better able to articulate their pain.

Which of the following is true regarding the interaction between infused fluids, volume status and interstitium?

Annually in the UK, around half a million children and infants undergo general anaesthesia. The provision of anaesthesia for this patient group can be a daunting task; the size of the patient is very variable, disease states and pathology are present that are not seen in other areas of practice, and there are substantial challenges of communicating and allaying anxiety. Additionally, unique medicolegal concepts exist. As those charged with the patients care during unique situations, it is important for anaesthetists to have a holistic understanding of the treatment they will be providing.