Local anaesthetic drugs can be used to perform a reversible blockade of motor and sensory nerves. Local anaesthetic drugs act by temporarily blocking sodium channels in excitable tissues such as nerves and muscle. This prevents the influx of sodium across the cell membrane, leading to an inhibition of action potential propagation along axons of nerves. Local anaesthetic can be used for infiltration. This is where the drug is infiltrated into an area of skin to block sensation and pain. There are many different local anaesthetic agents. The two commonly used drugs for local infiltration include lidocaine, also known as lignocaine and bupivacaine.<\/p>\r\n
Once you have watched this video, why not attempt the multiple choice quiz to test your knowledge?<\/p>\r\n","protected":false},"excerpt":{"rendered":"
Local anaesthetic drugs can be used to perform a reversible blockade of motor and sensory nerves. Local anaesthetic drugs act by temporarily blocking sodium channels in excitable tissues such as nerves and muscle. This prevents the influx of sodium across the cell membrane, leading to an inhibition of action potential propagation along axons of nerves. […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2,1],"tags":[],"class_list":["post-59","post","type-post","status-publish","format-standard","hentry","category-tomorrows-clinicians","category-uncategorized","entry"],"youtubeVideo":"511047472\/dcc22b21ab","question1":"Local anaesthetic agents perform a reversible blockade of nerves by temporarily blocking what type of channels in excitable tissues?","answers1":" Sodium channels\r\n| Magnesium channels\r\n| Potassium channels\r\n| Calcium channels","correctAnswer1":"0","correctAnswerText1":"This prevents the influx of sodium ions across the cell membrane and inhibits propagation of action potential.","question2":"Local anaesthetic preparations containing adrenaline must NEVER be used at which site?","answers2":"Areas where there is significant bleeding\r\n| End arteries such as digits\r\n| Scalp wounds\r\n| Injecting into joint surfaces","correctAnswer2":"1","correctAnswerText2":"Local anaesthetic containing adrenaline must never be used at end arteries as the effect of adrenaline can cause ischaemia.","question3":"Which of the following is not a complication of local anaesthetic toxicity?","answers3":"Peri-oral tingling\r\n| Seizure\r\n| Cardiac arrhythmia\r\n| Rash","correctAnswerText3":"Local anaesthetic toxicity, which is usually due to excessive dosing or incorrect route of administration, causes cardiovascular symptoms such as hypotension and cardiac arrhythmias. Local anaesthetic toxicity can also affect the central nervous system, causing symptoms such as peri-oral tingling, tinnitus, strange taste, loss of consciousness and seizures.","correctAnswer3":"3","question4":"What is the maximum dose of lidocaine without adrenaline that can be safely given?","answers4":"7 milligram per kilogram\r\n| 5 milligram per kilogram\r\n| 3 milligram per kilogram\r\n| 1 milligram per kilogram","correctAnswer4":"2","correctAnswerText4":"The maximum dose of lidocaine WITHOUT adrenaline that can be safely administered is 3 milligram per kilogram. The maximum safe dose of lidocaine WITH adrenaline that can be given is 7 milligram per kilogram.","question5":"What is the maximum safe dose of bupivacaine that can be administered?","answers5":" 1 milligram per kilogram\r\n| 2 milligram per kilogram\r\n| 10 milligram per kilogram\r\n| 20 milligram per kilogram","correctAnswer5":"1","correctAnswerText5":"The safest maximum dose of bupivacaine is 2 milligram per kilogram irrespective of whether it contains adrenaline. ","question6":"Before infiltrating local anaesthetic into a forearm wound, what must you check for?","answers6":"Neurological status of the limb\r\n| Vascular status of the limb\r\n| Presence of foreign bodies\r\n| All of the above","correctAnswer6":"3","correctAnswerText6":"","question7":"Local anaesthetic may be contained within a glass vial. When opening these vials, the safest method is to use an opening device and by...","answers7":" Applying pressure at the tip of the glass vial\r\n| Applying pressure at the marked spot at the neck of the glass vial\r\n| Applying pressure at the base of the glass vial\r\n| Applying pressure at the middle portion of the glass vial","correctAnswer7":"1","correctAnswerText7":"The glass vial is designed to be opened by applying pressure at the marked spot at the neck. Pressure applied anywhere else can cause the vial to break, resulting in spillage and risk of injury from broken glass.","question8":"The static technique of performing a local anaesthetic infiltration involves...","answers8":"Inserting the needle into the skin and injecting the local anaesthetic\r\n| Inserting the needle and continuously moving it around while injecting the local anaesthetic\r\n| Inserting the needle and pulling the plunger back before injecting the local anaesthetic\r\n| None of the above","correctAnswer8":"2","correctAnswerText8":"The static technique consists of inserting the needle into the skin, pulling back on the plunger to check that the tip of the needle is not in a blood vessel before inserting the local anaesthetic. Injection of the local anaesthetic should form a skin bleb and blanche the surrounding skin.","question9":"The continuous technique of performing a local anaesthetic infiltration involves...","answers9":" Inserting the needle into the skin and injecting the local anaesthetic\r\n| Inserting the needle and continuously moving it around while injecting the local anaesthetic\r\n| Inserting the needle and pulling the plunger back before injecting the local anaesthetic\r\n| None of the above","correctAnswer9":"1","correctAnswerText9":"The continuous technique of injecting local anaesthetic involves inserting the needle into the skin and continuously moving it. Any accidental injection into a blood vessel is transient as the needle is being continuously moved. A skin bleb should form and the nearby skin will blanche.","question10":"After infiltration of local anaesthetic into a superficial forearm wound has taken effect, the patient should experience...","answers10":"Sensation of deep pressure\r\n| Sensation of sharp pain\r\n| Sensation of both sharp pain and deep pressure\r\n| Sensation of permanent numbness","correctAnswer10":"0","correctAnswerText10":"Blockade performed by local anaesthetic is reversible and the sensation should be restored after the local anaesthetic wears off. The patient will still sense deep pressure but should not be able to sense any sharp pain if the infiltration has taken effect.","question11":"","answers11":"","correctAnswer11":"","correctAnswerText11":"","question12":"","answers12":"","correctAnswer12":"","correctAnswerText12":"","question13":"","answers13":"","correctAnswer13":"","correctAnswerText13":"","question14":"","answers14":"","correctAnswer14":"","correctAnswerText14":"","question15":"","answers15":"","correctAnswer15":"","correctAnswerText15":"","icon":"local-anaesthetic-infiltration","parentId":"","recapId":"421","_links":{"self":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/59"}],"collection":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=59"}],"version-history":[{"count":7,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/59\/revisions"}],"predecessor-version":[{"id":843,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/59\/revisions\/843"}],"wp:attachment":[{"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=59"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=59"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vapp.rguc.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=59"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}