BNF for Children 2011-2012

516 10.3 Drugs for the relief of soft-tissue inflammation BNFC 2011–201210 Musculoskeletal and joint diseases10.3 Drugs for the relief ofsoft-tissue inflammationand topical pain relief10.3.1 Enzymes10.3.2 Rubefacients, topical NSAIDs,capsaicin, and poulticesExtravasationLocal guidelines for the management of extravasationshould be followed where they exist or specialistadvice sought.Extravasation injury follows leakage of drugs or intravenousfluids from the veins or inadvertent administrationinto the subcutaneous or subdermal tissue. It mustbe dealt with promptly to prevent tissue necrosis.Acidic or alkaline preparations and those with an osmolaritygreater than that of plasma can cause extravasationinjury; excipients including alcohol and polyethyleneglycol have also been implicated. Cytotoxic drugscommonly cause extravasation injury. Very young childrenare at increased risk. Those receiving anticoagulantsare more likely to lose blood into surroundingtissues if extravasation occurs, while those receivingsedatives or analgesics may not notice the early signsor symptoms of extravasation.Prevention of extravasation Precautions should betaken to avoid extravasation; ideally, drugs likely tocause extravasation injury should be given through acentral line and children receiving repeated doses ofhazardous drugs peripherally should have the cannularesited at regular intervals. Attention should be paid tothe manufacturers’ recommendations for administration.Placing a glyceryl trinitrate patch or using glyceryltrinitrate ointment distal to the cannula may improvethe patency of the vessel in children with small veins orin those whose veins are prone to collapse.Children or their carers should be asked to report anypain or burning at the site of injection immediately.The first method may be appropriate following extravasationof vesicant drugs and involves administrationof an antidote (if available) and the application of coldcompresses 3–4 times a day (consult specialist literaturefor details of specific antidotes). Spreading and dilutingthe offending substance involves infiltrating the areawith physiological saline, applying warm compresses,elevating the affected limb, and administering hyaluronidase(section 10.3.1). A saline flush-out technique(involving flushing the subcutaneous tissue with physiologicalsaline) may be effective but requires specialistadvice. Hyaluronidase should not be administered followingextravasation of vesicant drugs (unless it is eitherspecifically indicated or used in the saline flush-outtechnique).10.3.1 EnzymesHyaluronidase is used for the management of extravasationFor preparations, see BNF section 10.3.1.10.3.2 Rubefacients, topicalNSAIDs, capsaicin, andpoulticesClassification not used in BNF for Children.Management of extravasation If extravasation issuspected the infusion should be stopped immediatelybut the cannula should not be removed until after anattempt has been made to aspirate the area (through thecannula) in order to remove as much of the drug aspossible. Aspiration is sometimes possible if the extravasationpresents with a raised bleb or blister at theinjection site and is surrounded by hardened tissue, butit is often unsuccessful if the tissue is soft or soggy.Corticosteroids are usually given to treat inflammation,although there is little evidence to support their use inextravasation. Hydrocortisone or dexamethasone (section6.3.2) can be given either locally by subcutaneousinjection or intravenously at a site distant from theinjury. Antihistamines (section 3.4.1) and analgesics(section 4.7) may be required for symptom relief.The management of extravasation beyond these measuresis not well standardised and calls for specialistadvice. Treatment depends on the nature of the offendingsubstance; one approach is to localise and neutralisethe substance whereas another is to spread and dilute it.