Okay, so I have been ditching my posting duties. It has been a few months and you haven't heard one lick from me. I know, I know. You were wondering if I was abducted by aliens. Well, they did land in my backyard: I offered them lemonade, and sent them on their way, but inadvertently, no abductions. (Image taken from http://noliesradio.org/archives/1954)
Sorry, I know you're disappointed: I have no alien anal probe experiences to share, but I can tell you about a lot of colonoscopies I have assisted in if you're interested. Man, there were some colons that would reek so bad that--. Wait, you want me to talk about wound closure instead? Are you sure? I mean I can really give you a riveting story about the day that the Sick Colon Struck Back.
Oh, alright. Fine. Be that way. See if I ever tell you about colons again. ;)
Wound Care: Anesthesia
Since we have past the medieval ages, we have ways of numbing wounds. When I was looking up videos for lidocaine injections, I found a great site that gave the following list of subjects:
1. Inject insulin
2. Inject local anesthetic into a wound
3. Pick locks with a strategically placed bump key
4. Prepare an insulin syringe to inject a diabetic cat.
(Image derived from http://www.watercure2.org/pet_testimonials.htm)
Yes, that is the actual list. Hmmm, so let's ask: which of these doesn't belong? The picking locks or the diabetic cat? I think I will go with the cat. (please see: http://www.wonderhowto.com/topic/inject-lidocaine/). (Image taken from http://thegreatgeekmanual.com/blog/motivational-poster-lock-picking)
Back to the blog at hand: Last time we discussed wound irrigation and the different types of antiseptics. So I am going to leave that out of this discussion, except to say: Please irrigate and clean the wound before administering anesthetic.
Okay. Okay. There are a bunch of whiners out there that couldn't handle a wound cleaning if their life depended on it. So in their case, just sterilize your injection site first then give the local anesthetic then clean them. Whine whine complain.
But for everyone else:
3. Prep the area with an antiseptic.
4. Prepare a 27 or 30-gauge STERILE UNUSED needle synringe with around 3 cc of anesthetic. (Wipe the top of the anesthetic bottle with alcohol pad before inserting the needle. Draw out 3 cc or more solution.)
5. Infiltrate the skin (epidermis) at the edge of the wound with the needle bevel side up.
6. Create a skin wheal by slowly injecting approximately 0.5 cc of anesthetic into the area. (Note: To all the trigger fingers out there, refrain from turning the injection into a Nascar race. Rapid injection produces painful swelling of the tissues.)
7. Redirect the needle within the wheal if needed. Once the first wheal is created, you can always redirect the needle within it towards a different direction and add an additional 1 cc of local into the dermis. If needing to re-enter the skin for further injections, try to re-enter a site that is already blanched or part of the wheel you made previously. This will prevent further pain, because you will be entering a site that is more likely to be numb.
8. Go get a hamburger. Enjoy a good movie. No, just kidding, but you can afford to wait a couple minutes for the anesthetic to take affect. A good injection will leave a thick wheal line around the edges of the wound and take into account its depth.
9. Gently poke the wound area that you intend to suture with a sterile needle (you can use the one you injected them with). Now, this doesn't mean go for the gold and poke 'em like you mean it. Gently means gently.
The patient should feel pressure but nothing sharp. If they feel something sharp, one they may slug you; and two, you need to add more local to the area.
Anyway, I promised you that I would discuss lidocaine. Truthfully, I thought about running to South America before giving the lidocaine interview, but alas, the border patrol saw I was an Amercan with out papers and I got deported. :)
Lidocaine vs. Bupivicaine
This is the "Tastes great. Less filling" debate of wound care. You may see the anesthetic protests and WWF smackdowns at a local hospital if you are lucky. I think I saw a surgeon take out an ER doc over this once.
These two are the most commonly used local anesthetics. Lidocaine being the very most common. In fact, it is widely used for the majority of cases, but Bupivicaine is used in situations that needed a longer duration of coverage. Those type of situations generally involve complex wounds that would require a greater amount of time to close.
I have been known to make a Lidocaine-Bupivicaine cocktail. Mix in a little epinephrine and some Sodium Bicarbonate and my patients love it. Shaken not stirred.
Lidocaine with epinephrine (the most popular, kind of like the Homecoming Queen of anesthetics) generally lasts 2-6 hours.
Bupivacaine (Marcaine) with epinephrine generally lasts anywhere from 3 hours to 7 hours.
Note: if you want to be nice to your patient and you have it on stock, add some Sodium bicarbonate to the mixture. You just draw enough Sodium bicarb to cause the clear solution to turn cloudy. That is the chemical reaction of the Sodium bicarb neutralizing the acidity of the anesthetic, thus relieving the burning sensation of the acidic local.
So, let's take the ' why epinephrine?' quiz:
Why do you want to include epinephrine?
A. Because the pharmaceutical companies told you so.
B. It blanches the skin, helping you to better identify which areas that have been numbed.
C. Because it decreases bleeding. Nothing says, blood go away like epinephrine.
D. It increases the maximum dose of local you can apply to the area. It vasoconstricts blood vessels thus preventing systemic absorption of the anesthetic.
E. All of the above.
F. B,C, D and forget about A
The answer is F. Sorry to all those that chose A. I know, you were tempted to break down the pharmaceutical company doors for forcing you to add epinephrine to local anesthetics, but we must refrain.
When considering whether or not to use a mixture with epinephrine in it, please remember one important rule:
Epinephrine should NEVER be used in the following areas: Ears, Nose, Fingers, Toes and male anatomical parts.
Top Five reasons why you don't want systemic absorption of lidocaine:
1. Wastes lidocaine. Hello, you're in the middle of a disaster. Is the pharmacy going to be open. ;)
2. Aliens don't approve.
3. Your mother told you not to.
4. Because the cows might attack. Udderly terrifying. (Image taken from http://www.robmillard.com/archives/cat-off-the-wall-insights.html)
5. Lidocaine is used to treat disturbances in heart rhythms and can stop a normal working heart.
I don't know, I think number 4 is the most important. ;) Those cows can be dangerous.
Interestingly enough, lidocaine decreases the sensitivity of cardiac muscle to electrical impulses. No. We don't want insensitive hearts. We need sensitive hearts to cry, to love, and to live.
Lidocaine acts by slowing the conduction of electrical signals within heart muscle. Thus, it helps restore the heart's rhythm in conditions such as irregular and incresed contraction of the ventricles (ventricular tachyarrhythmias). (please see http://www.netdoctor.co.uk/medicines/100001501.html for more information on lidocaine and heart arrythmias, and also http://en.wikipedia.org/wiki/Lidocaine)
Here are a few good sites providing more information on anesthetics:
How Anesthetics work and their History
Why you shouldn't go Butt-crazy in administering local anesthetics
The following are some really great videos further explaining the administration of local into a wound as well as the basics of suturing. Yes, I'm being lazy. If there is a good video out on the subject, why should I have to write it? Besides, the aliens say no more writing until the mind probe is activated.
So until next time. TTFN.
Injecting a local anesthetic into a wound:
Basic Suture Technique:
Suture Technique Part 2