[need to shorten this post & stick to the subject, so edited it somewhat].
use of "super"/"crazy" glue (cyanoacrylate) is an old trick. long before Doctors were using it to close some types of wounds and incisions (one type is call "Derma-bond" by medical personnel), other more resourceful types (who did not have to worry about malpractice law suits and insurance premiums) were using it when a suture kit was not available.
so, it's a legitimate suggestion. good point, David - glad you brought it up.
generally, as David pointed out, you shouldn't get it inside of the wound. i have messed up and gotten in the wound (i'm a bit of a klutz). no ill effects.
if you have a painful cut/broken blister/toe nail coming off (many other possible injuries), the superglue will stabilize the wound as well as prevent oxygen from entering it, pain is reduced markedly. i've used it to glue two big toe nails back on (amongst numerous other injuries - i'm a klutz, remember) for a period of time before the injury started to heal somewhat. you'll need to re-apply it anywhere from daily to every 3-4 days depending upon the site, nature, and severity of the injury. oh...also, because it prevents oxygen from entering the wound, it shouldn't be used to seal a puncture wound - never good to seal a puncture wound from the top. very nasty bacteria can thrive in that anaerobic (no-oxygen) environment when a puncture wound is sealed from the top. so, don't seal a puncture wound with superglue. it's difficult to thoroughly clean and disinfect a puncture wound.
also, as was previously pointed out by David, make sure the the wound is CLEAN and DISINFECTED before applying the superglue or any other bandages/wound dressings. as the wound size gets (not grows, i'm referring to the initial size of the wound) larger, it becomes much more difficult to close.
depending upon the circumstances (wound size and your location; how far to a ranger station, professional med help, etc.) it may or may not be advisable to use superglue to attempt to close a large wound.
[later edit: "large wound" this is a poor choice of words on my part, as it is too vague. one picture is in my mind, another "picture" may be in the mind of the reader. certainly, any wound penetraing deep tissue is not a candidate for closing. i could elaborate here, but the "Doc", who was kind enough to reply further on, with some very helpful and expert info covers it much better than i ever could - so, be sure to read his posts.]
sometimes it's just better to clean, disinfect, and cover it so that no dirt can get into it. you must then be careful crossing water sources (streams, rivers, etc.). if you can seal it in a plastic bag using duct tape to keep it dry while you cross the stream, that would be good.
also, next time you're at a doctor's appt, ask your physician for some pointers on cleaning, disinfecting, closing (using superglue), and bandaging wounds/cuts. have him show you how large/deep a wound you should attempt to close. obviously, these "Docs" are real pros at this (esp. ER/Trauma Docs - wish we had one or two particpating regularly in a Thread devoted to Wilderness First-Aid & Medicine - or a regular "column" in the BPL on-line mag; each month/issue covering a different aspect (with pictures!) of Wilderness First-Aid & Medicine).
after cleaning and disinfecting the wound and before applying the superglue, try to "line up" the edges of skin/wound to be "closed" so that the position of the skin looks as much as possible like it did before the wound [see the "Doc's" more explicit instruction in another post in this Thread about when it is advisable to try to "line up" the edges of the wound]. if you can use only one hand, it's a little difficult and you may need the assistance of a hiking "bud", if you're not out solo on that trek.
[note: a deep, penetrating wound should not be closed in the field as a pocket, susceptible to infection and which also won't heal quickly/properly may be left beneath the closed wound. see elsewhere for how to deal with a gaping or deep penetrating wound.]
after applying the superglue, hold the wound in postion for maybe 20seconds - it bonds real fast on skin. if too much glue came out, have a clean tissue handy & immediately just touch the excess with the tissue - it soaks in pretty quickly. if too much glue is NOT used on the skin, then it dries plenty fast. Best course of action if too much is used is to, once again, just touch the corner/edge of a piece of tissue to the excess glue to soak it up via capillary action. don't place the tissue flat on the wound/skin or it will end up sticking to the skin. you'll have to scrape it off & you don't want to do that on/around the wound (unless you've been bad and want to punish yourself).
the liquid superglue dries faster than the gel, but runs more easily & gets were it shouldn't (esp. if one is a klutz, like me). i've used both. don't get it or the concentrated fumes near plastic (many eye-glass lenses are made out of plastic. the fumes need to ventilate into a larger air volume. many plastics will be damaged by the concentrated fumes.
also, make sure that you and anyone else who will assist in cleansing, treating, and closing the wound disinfect their hands with alcohol gel, first, before coming near the wound. you should disinfect the area around the wound also.
well...'nuff said on superglue. hope you took notes. there will be a test later on.
hope this info helps some.
Roger, makes a good point on infection and drainage. for large or deep wounds, Dr's usually put one or more "drains" in the wound to allow fluid/serum, blood, and pus to drain from the wound. a drain can be nothing more than a strip of gauze. i've found that larger wounds open partly nearly daily or the next day if in an area that experiences a lot of movement (obviously if an ER had been handy & they were stitched/stapled then they wouldn't open). smaller wounds stay closed up to 3-4 days. smaller wounds are often not as deep, large, or long and easier to clean. while i've never had a wound become infected, it is a possibilty. remember to clean and disinfect before either closing and/or dressing the wound. you could also use wound closure strips or butterfly bandages to close a wound. this would probably be a real Dr's recommendation. in most cases, i prefer superglue as long as was stressed above the wound can be CLEANED and DISINFECTED properly. remember, the wound must be closed within 6-8 hours or it cannot be closed due to the much higher risk of infection. allowing the wound to heal without closing it will increase the healing time. exceptions to the 6-8 hour rule are the scalp & face. the rule there for wound closure is around 24hrs as i recall. there is more to wound treatment that is beyond the scope of this thread. so please, don't take this post as an all encompassing dissertation on wound care. talk to your Dr. or find a good book on backcountry/wilderness medicine. sorry, i can't recommend any book since i'm not familiar with any.
LET ME ADD ONE MORE THING HERE: there are times when emergency measures need to be taken which otherwise would be inadvisable. a decision needs to be made. sometimes it's the right one; sometimes the wrong one. this discussion has focused on ONE POSSIBLE decision in an emergency situation lacking more appropriate options. it's more a "what CAN be done." rather than under different circumstances a "is this really a good idea?" for example, if at home & can get to an ER is it advisable to boil fresh garlic & use the water to irrigate a wound? or, use honey to keep the wound sterile? or, use some sphagnum moss (contains low levels of iodine) to help combat infection? or, make a poltice out of "boneset" and/or other medicinal wild herbs? of course not. modern medical means are generally superior. my point is just that there are times to use both non-traditional or other methods that normally wouldn't be employed in a different environment. however, perhaps, in my hurry to post, i've explained this poorly. from the responses, apparently i have. my apologies.]
please don't understand this post to mean that superglue is a panacea for any and all trauma including, but not limited to cuttings, woundings, slashings, burnings, lacerations, abrasions, and penetrations. i feel that, under some circumstances it is an overlooked option. like, if i hadn't had superglue when i lost both big toe nails, i'd still be stuck in the deep woods and y'all wouldn't have the great displeasure of reading this post.
as 'Tigger' used to say: "TTFN - ta ta for now".
[note: i'm still not happy with some of the wording here in this post. i think perhaps some confusion results from such non-specific words, such as large, deep, small - these words mean one thing to a Med. Pro. & another to the hiker. to an ER Doc who sees this stuff frequently, what i'm calling large, might be considered to be minor/small. for me, if it happened at home & it requires a trip to the ER, it's more than minor. it's already far too long & adding more detail on "what constitutes large and small wounds" would only add to it. please be sure to read the "Docs" excellent comments further on. ]