Best practice & research. Clinical anaesthesiology
-
Best Pract Res Clin Anaesthesiol · Sep 2003
Case Reports Comparative StudyIntrathecal neurolytic blocks for the relief of cancer pain.
Intrathecal neurolytic blocks for the treatment of chronic pain were first described by Dogliotti in 1931. Since then, many authors have described the intrathecal injection of various neurolytic substances for the treatment of oncologic pain. In recent years, alcohol and phenol have been the substances most commonly used for this purpose. ⋯ Four cases of cancer patients whose intractable pain was treated by the authors using intrathecal neurolysis are presented. Pertinent literature is reviewed. In this account, the emphasis is on proper selection of patients and techniques.
-
The use of spinal anaesthesia in children has been primarily limited to situations in which general anaesthesia was considered to pose an excessive risk. The ex-premature infant and the neurologically impaired child account for the majority of spinal anaesthetics used today. Spinal anaesthesia, compared with general anaesthesia, in the ex-premature infant undergoing inguinal hernia repair has decreased postoperative respiratory complications (e.g. apnoeic events, prolonged mechanical ventilation). ⋯ Advances in spinal needle design have decreased the incidence of postdural puncture headache (PDPH). Catastrophic events have occurred with neuraxial techniques. Care must be taken in evaluating the relative risks of anaesthetic approaches in infants and children.
-
The elderly are an expanding population of patients presenting for anaesthesia. The pharmacokinetics of anaesthetic agents in the elderly deserves special attention because the normal ageing process and the effect of age-related diseases affect organ systems in a heterogeneous way with unpredictable consequences. The pharmacokinetics of each drug is also affected by these changes in a specific way and, together with the pharmacodynamic consequences, makes drug use and drug dosing challenging in this population. Although a decrease in bolus and infusion rates is a common theme, only pharmacokinetic modelling of drug disposition in the elderly will provide accurate dosing guidelines and increase the margin of safety.
-
Best Pract Res Clin Anaesthesiol · Jun 2003
ReviewCognitive function after anaesthesia in the elderly.
Despite advances in peri operative care, a significant percentage of elderly patients experience transient post operative delirium and/or long-term post-operative cognitive dysfunction (POCD). This chapter reviews the aetiology, clinical features, preventive strategies and treatment of these syndromes. Pre-operative, intra-operative, and post-operative risk factors for delirium and POCD following cardiac and non-cardiac surgery are discussed. ⋯ Currently there is no single therapy that can be recommended for treating post-operative cognitive deterioration. Primary prevention of delirium and POCD is probably the most effective treatment strategy. Several large clinical trials show the effectiveness of multicomponent intervention protocols that are designed to target well-documented risk factors in order to reduce the incidence of post-operative delirium and, possibly, POCD in the elderly.
-
An overview is given of the influence of age on the pharmacodynamics of drugs used during general and locoregional anaesthesia. For some groups of agents a distinct separation into age-related changes in the pharmacokinetics and pharmacodynamics is possible, whereas for others the literature indicates only that responses in the elderly are enhanced. I start with an overview of the influence of age on cardiovascular and neuroendocrine function and include a short account of the state-of-the-art in pharmacodynamic modelling. ⋯ For opioids and local anaesthetics applied for blockade of the central nervous system, the pharmacodynamic involvement is not always clear. For neuromuscular blocking agents, pharmacodynamic involvement appears to be nearly absent in the reduced dose requirements seen with age--so that the latter appear to be caused by altered pharmacokinetics. Future studies, using pharmacokinetic-pharmacodynamic (PK-PD) mixed-effects modelling, should further explore this area to obtain clinically applicable data for improving our insight into the delivery of anaesthetics to the elderly and improving the quality of anaesthesia in this fast-growing population.