JAP  Volume 7 Issue 1 Feature


Paracetamol Paracetamol was discovered in Germany in 1883, but became


commercially available in 1947 and today it is one of the most commonly used safe analgesic drug. The acronym “PARACETAMOL” explains its pharmacology.


P Primary simple analgesic Prostagandin E synthesis inhibitor in anterior hypothalamus (central antipyretic effect)


A Absorption is rapid from gut in 30 minutes R Renal and hepatic function need to be normal for maximum safe dose


A Analgesic adjunct post-op C Cyclo-oxygenase-3 inhibition (recently discovered) is another mechanism of action Crosses blood brain barrier as it is lipid soluble and non-ionised


E Excretion is < five percent unchanged in urine T T1/2 (elimination) is nearly two hours A Antidote is N-acetyl cysteine and methionine M Metabolised to glucoronide, sulphates and N-acetyl-p. benzoquinone imine in liver


O Oral bioavailability is 70-90 percent Opiates requirements are decreased when used in combination therapy


L Liver toxicity results in irreversible centri-lobular necrosis Peri-operative hypothermia


Anaphylactic Reaction Anaphylaxis is a severe, life threatening, generalised or systemic


hypersensitivity reaction. This is characterised by rapidly developing, life-threatening airway and/or breathing and/or circulatory problems usually associated with skin and mucosal changes. Precipitants include insect bites, foods/additives, drugs, and IV infusions and blood products. This acronym must not be considered as an alternative to the already existing guidelines for anaphylaxis. Remember “REACTIONS”.


R Respond quickly and appropriately following ABC approach Remove the trigger for anaphylactic reaction


E Eminent airway obstruction can happen due to angio-oedema (12 percent of anaphylaxis)


A Adrenaline 0.5mg IM (1:1000 solutions) is first line of treatment


C Chlorpheneramine and hydrocortisone are part of management (both IV given)


T Treat bronchospasm with nebulised Salbutamol I


Icatibant (bradykinin receptor blocker, licensed in EU) 30mg SC Inotropic and vasopressor support should continue if not responding to treatment Investigate for mast cell tryptase (immediate sample, one to two hours and then 24 hours later) Idiopathic anaphylaxis (no cause found) could be up to 20 percent of reactions


Hypothermia exists when the body’s usual thermoregulatory mechanisms are unable to maintain heat in a cold environement and the core temperature falls below 35ºC. Peri-operative hypothermia does have implications for anaesthetists. The following acronyms may remind us of a few medical situations contributing to hypothermia. Remember “HYPOTHERMIA”.


H Hypothyroidism is a contributing factor Y Young age group is affected as a result of drugs e.g. phenothiazines and alcohol


P Pituitary dysfunction may lead to hypothermia O Open laparotomies and thoracotomies T Transfusion of cold stored blood is another cause H Hepatic failure may cause hypothermia E Extremes of age i.e. elderly and neonates are vulnerable to hypothermia


R Room temperature (cold) will contribute to hypothermia M Metabolic derangement e.g. hypoglycaemia can contribute to hypothermia


I


Inspired anaesthetic gases (cold) will contribute to hypothermia


A Arrhythmias such as AF and even VF could happen as a result 20 www.japractice.com


O Oxygen is an essential part of treatment N Nor-adrenaline infusion to start if vasodilatation not responding to treatment


S Specific allergy clinics should be involved for follow up


Regional vs general anaesthesia in obstetrics Regional analgesia/anaesthesia is considered to be the benchmark technique in labour and delivery suite. We have developed a few mnemonics to remember the advantages of RA and the risks associated with GA. All mnemonics start with “A” which makes them easy to remember.


Clinical Advantages of RA over GA Airway difficulty


It is anticipated in parturients that the airway management will be more difficult due to soft tissue oedema around neck, mouth and oropharynx. Enlarged breasts can make laryngoscopy difficult too. Functional residual capacity is low in pregnancy and the patient becomes hypoxic sooner than a not-pregnant counterpart. Regional analgesia and anaesthesia obviate this problem. Aspiration pneumonitis A pregnant patient undergoing emergency caesarean section


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44