Analgesia anaesthesia

Local anaesthetics are drugs that reversibly interrupt impulse propagation in peripheral nerves thus leading to autonomic nervous system blockade, analgesia, anaesthesia and motor blockade in a desired area of the organism. 

Decreased breathing rate as brought on by analgesia/anaesthesia. 

G. W.A. Kenny, G.N.C. McArdle, C.S. The influence of patient characteristics on the requirements for postoperative analgesia. A reassessment using patient-controlled analgesia. Anaesthesia 1989, 44 (1), 2-6. 

Wigfull J, Welchew E. Survey of 1057 patients receiving postoperative patient-controlled epidural analgesia. Anaesthesia 2001 56(l) 70-5. 

Millo J, Siddons M, Innes R, Laurie PS. Randomised double-blind comparison of ondansetron and droperidol to prevent postoperative nausea and vomiting associated with patient-controlled analgesia. Anaesthesia 2001 56(l) 60-5. 

Higgins MJ, Ashury AJ, Brodie MJ. Inhaled nebulised fentanyl for postoperative analgesia. Anaesthesia 1991 46(ll) 973-976. 

Worsley MH, MacLeod AD, Brodie MJ, Ashury AJ, Clark C. Inhaled fentanyl as a method of analgesia. Anaesthesia 1990 45(6) 449-451. 

Harrison, P. D. (1975) Paraplegia following epidural analgesia. Anaesthesia, 30, 778. 

Intrathecal (IT) Into the subarachnoid space between two of the membranes (meninges) separating the spinal cord from the vertebral column. This route is used for drugs that do not penetrate the blood-brain barrier, but which are required for their central action (e.g., antibiotics). Drugs can also be injected spinally (into the epidural space) for local anaesthesia or analgesia. 

Shulman, M., and M.S.Sadove. 1967. 1,1,1,2-Tetrafluoroethane an inhalation anesthetic agent of intermediate potency. Anaesthesia Analgesia 46 629-633. 

Intrathecal A form of intraspinal anaesthesia or analgesia in which the agent is injected through the dura mater and arachnoid membrane into the cerebro-spinal fluid which surrounds the spinal cord. 

Paech MJ, Lim CB, Banks SL, Rucklidge MW, Doherty DA. A new formulation of nasal fentanyl spray for postoperative analgesia a pilot study. Anaesthesia. 2003 58 740-744. 

Senagore AJ, Delaney CP, Mekhail N, et al. Randomized clinical trial comparing epidural anaesthesia and patient-controlled analgesia after laparoscopic segmental colectomy. BrJ Surg. 2003 90 1195-1199. 

Most TA referred herein (e.g. hyoscyamine, scopolamine, N-buty 1-scopolamine, Fig. 1) primarily act as competitive antagonists of acetylcholine (anticholinergics) in the synaptic cleft (parasympatholytic) [29, 35], Thus therapeutic effects may include mydriasis, spasmolysis of the respiratory system, GIT and overactive bladder, anaesthesia and analgesia [33],... 

Anisodamine is a natural derivative of hyoscyamine mono-hydroxylated at the tropane skeleton (Fig. 1). The compound was extracted from traditional Chinese medicine Anisodus tanguticus evoking typical non-specific effects of cholinergic antagonists (spasmolysis, anaesthesia, mydriasis, analgesia) in combination with... 

Hall, L. (1971). Wrighfs veterinary anaesthesia and analgesia (7th ed.). London Tindall. 

Stacey R, Jones R, Kar G, Poon A. High-dose intrathecal diamorphine for analgesia after Caesarean section. Anaesthesia 2001 56(l) 54-60. 

METHOTREXATE ANAESTHETICS-NITROUS OXIDE t antifolate effect of methotrexate t toxicity of methotrexate Nitrous oxide is usually used for relatively brief durations when patients are anaesthetized, and hence this risk during anaesthesia is minimal. However, nitrous oxide may be used for analgesia for longer durations, and this should be avoided... 

Phencyclidine ( angel dust ) was made in a search for a better intravenous anaesthetic. It is structurally related to pethidine. Phencyclidine was found to induce analgesia without unconsciousness, but with amnesia, in man (dissociative anaesthesia). The postoperative course, however, was complicated... 

Balanced surgical anaesthesia (hypnosis with analgesia and muscular relaxation) with a single drug requires high doses that will cause adverse effects such as slow and unpleasant recovery, and depression of cardiovascular and respiratory function. In modem practice, different drugs are used to attain each objective so that adverse effects are minirnised. 

Usually intravenous pre-oxygenation followed by a small dose of an opioid, e.g., fentanyl or alfentanil to provide analgesia and sedation, followed by propofol or, less commonly, thiopental or etomidate to induce anaesthesia. Airway patency is maintained with an oral airway and face-mask, a laryngeal mask airway (LMA), or a tracheal tube. Insertion of a tracheal tube usually requires paralysis with a neuromuscular blocker and is undertaken if there is a risk of pulmonary aspiration from regurgitated gastric contents or from blood. 

Dissociative anaesthesia is a state of profound analgesia and anterograde amnesia with minimal hypnosis during which the eyes may remain open (see ketamine, p. 353). It is particularly useful where modem equipment is lacking or where access to the patient is limited, e.g. at major accidents or on battlefields. 

Uses. Nitrous oxide is used to maintain surgical anaesthesia in combination with other anaesthetic agents, e.g., isoflurane or propofol, and, if required, muscle relaxants. Entonox provides analgesia for obstetric practice, for emergency management of injuries, and during postoperative physiotherapy. 

Dosage and administration. For the maintenance of anaesthesia, nitrous oxide must always be mixed with at least 30% oxygen. For analgesia, a concentration of 50% nitrous oxide with 50% oxygen usually suffices. 

Ketamine is a phencyclidine (hallucinogen) derivative and an antagonist of the NMDA-receptor. In anaesthetic doses it produces a trance-like state known as dissociative anaesthesia (sedation, amnesia, dissociation, analgesia). 

Extradural (epidural) anaesthesia is used in the thoracic, lumbar and sacral (caudal) regions. Lumbar epidurals are used widely in obstetrics and low thoracic epidurals provide excellent analgesia after laparotomy. The drug is injected into the extradural space where it acts on the nerve roots. This technique is less likely to cause hypotension than spinal anaesthesia. Continuous analgesia is achieved if a local anaesthetic, often mixed with an opioid, is infused through an epidural catheter. 

Holley, F.O. van Steennis, C. Postoperative analgesia with fentanyl pharmacokinetics and pharmacodynamics of constant-rate IV and transdermal delivery. Br. J. Anaesthesia. 1988, 60, 608-613. 

Andersen R, Krohg K. Letter Post-operative analgesia combined with doxapram. Anaesthesia 1976 31(1) 114-15. 

Kuczkowski KM. Respiratory arrest in a parturient following intrathecal administration of fentanyl and bupivacaine as part of a combined spinal-epidural analgesia for labour. Anaesthesia 2002 57(9) 939 0. 

Hewer CL. In Recent Advances in Anaesthesia and Analgesia. Chmchill London, 1948 35. 

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