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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES 9. - Wound Healing
RADIO 4
TUESDAY 08/02/05 2100-2130
PRESENTER:
MARK PORTER
REPORTER: ALI AYRES
CONTRIBUTORS:
Gus McGrouther
SIMON CARLEY
NICK RANKIN
PHILIPPA POTTER
CHARLES RANOBOLDO
CATHERINE COLLINS
PRODUCER:
GERALDINE FITZGERALD
PAULA MCGRATH
NOT CHECKED AS BROADCAST
PORTER
Hello. Today's programme looks at wound healing.
I'll be finding out how the body repairs itself, and about the latest techniques used by surgeons to help the process.
CLIP
I can remember as a child being held down in an emergency department kicking and screaming while somebody put stitches into my face for a wound which nowadays would be cleaned, probably with minimal effort and discomfort, and would be simply glued and out the door.
PORTER
I'll be discussing the difference between stitches, glue and staples, and which are best for what - and asking why accident and emergency departments now clean wounds with water instead of antiseptic.
While Ali Ayres discovers what hospitals are doing to combat wound infections, like the notorious MRSA.
But first a salutary lesson - basic cleansing and the use of the right materials in the right place by someone who knows what they are doing all help a wound heal quickly. Poor cleansing, the use of the wrong materials in the wrong place by an inexperienced doctor or nurse is likely to have the opposite effect, and leave you with a permanent reminder. As Nick Rankin found out when he fell off his bike 30 years ago.
RANKIN
I was on a bicycle coming very fast down a hill and a car was coming the other way and somehow I put my feet down and I went straight over the handlebars. And so I ploughed up this Suffolk road with my face. What had happened was I'd hit the road, I'd cut my hair off, a mask of blood and hair and dust everywhere. But anyway I'd cut my forehead, I'd gauged my nose and I'd bitten through the inside of my lip. So I was a complete mess. My father drove me to the surgery to be sewn up. And he tried to use stitches on the inside of my lip, now that's very, very soft, it's almost like blubber and the stitches just didn't work, they just came out, they just cut through. But he put two stitches in my forehead, it's still very, very lumpy and about two weeks afterwards I remember feeling there was a big lump there and pulling out a piece of gravel - black with blood around it - and a little grainy pebble that came out. But as a result, 30 years on, I have a lumpy scar. I mean some people's scars are flat because they're sewn well, this was a bodged job.
PORTER
Simon Carley is a consultant at the Manchester Royal Infirmary Accident and Emergency Department and an expert in dealing with a wide variety of wounds. I asked him how he decides on the best approach.
CARLEY
So in terms of what we're looking at we're really thinking about how likely this wound is to get infected, how likely this wound is to be able to be closed with simple methods, such as steristrips, which you can use in areas which aren't particularly stretchable, so you couldn't use them say on an elbow but you could use them on say the forearm, which doesn't have a great deal of movement in. So it depends a lot on what the wound is like in what we actually decide to do.
I suppose if you wanted to know what my favourite ways are, I suppose the nice ones are the ones which are nice, clean straight wounds on a very simple area of the body that you can just clean with simple tap water and just glue, because that's a very good result for the patient, you get a great cosmetic outcome and it can all be over and done in 10-30 minutes. Although sometimes it's quite satisfying when you see say a nasty facial injury, which may not be a straight wound, it may be a star shaped wound, which may take a long time to sort out but you can great results from. I remember a young girl who got hit with a hockey ball and ended up with like a 10 centimetre laceration on her forehead, took us a long time to close that but she came back and saw me the other week and it's a fantastic result, you could hardly see the scar at all.
PORTER
What about using staples to hold the wound edges together?
CARLEY
Staples are great, staples are a very effective way of getting the wound closed but cosmetically they're not fantastic. We tend to use them in A&E principally for scalp wounds, so somebody who's had a nasty injury, often with fighting unfortunately in our present society, but you can get those closed quite quickly and cosmetically on the scalp it probably doesn't matter as much as say on the face - I mean we'd never dream of using staples on somebody's face for instance.
PORTER
Cosmetic considerations aside, how else does the site of the wound influence your approach to repairing it?
CARLEY
The ability of the body to heal varies enormously, depending on where your cut is. If you take the best option, which would be somewhere like the face or the head, there's a fantastic blood supply there, which is why it bleeds so much when you cut it, but that's fantastic for healing and to some extent you can get away with a lot of things on the face and the scalp by using stitches to close it up and even if there's a little bit of debris around the blood supply's so great it'll cope with that. You take the opposite extreme and the classical example is the shin, which has got an appalling blood supply for the body, we're not terribly well designed in that respect, and if you even sort of think about trying to put stitches into a laceration on the front of the shin then by putting the sutures in you'll reduce the amount of blood supply getting to the wound edges and they fall apart after a few days. And it's sad because it's terribly tempting sometimes when you see these very nasty shin lacerations that you want to stitch it to make it look good for when the patient leaves the department but sometimes you've got to hold yourself back and say look don't do that today, what we'll do is we'll give it a really good clean, try and bring those wound edges together with just simple things like steristrips and if there's some gaps we'll leave them and we'll just let it heal up over a period of weeks, sometimes even months, and sometimes they even need skin grafts to close them, but if you went for stitches there - absolute disaster.
PORTER
Dr Simon Carley from the A&E department at Manchester Royal Infirmary.
My guest today is Gus McGrouther - Professor of Plastic and Reconstructive Surgery at the University of Manchester.
Gus - perhaps we can start with the basics. What are the processes involved in wound healing, how does a - for instance - a surgical incision heal?
MCGROUTHER
Well more primitive creatures are even cleverer than us. If you look at a tadpole, if it loses a part of its body it grows a new one. We have to heal, we don't grow new parts sadly, sadly. And we heal by forming a wound which has all sorts of cells growing into it and it ultimately becomes a scar. So effectively all the wounds that we get heal by scar formation.
PORTER
And it's that scar tissue that pulls the tissues together.
MCGROUTHER
The scar contracts and shrinks and pulls the tissue together and then the skin grows over the top.
PORTER
What sort of timescale are we talking about, I mean if I was to put a - have my appendix taken out, how long will it be before those tissues return to normal strength?
MCGROUTHER
We say that wounds heal in a week because there's a skin layer over the top in a week. But in fact the process goes on for weeks and months and it will even take up to a year before the redness is disappearing from the scar. So the whole process goes on and on.
PORTER
It was quite interesting, we heard Simon talking about using tap water to clean wounds in his accident and emergency department. When I was doing casualty we used antiseptic, why has that changed?
MCGROUTHER
We are doing trials comparing different treatments, but if you think about, let's say, a trial on aspirin, the only variable is whether the person has the pill or not, the problem with a wound is that there are all sorts of variables like what the patient had for lunch, like the anaesthetic they had and so you can't really do such successful controlled trials. And in fact NICE - the National Institute for Clinical Excellence - reviewed the evidence for wound care products about three years ago and came to the conclusion that there wasn't really evidence either for or against any particular product.
PORTER
This is antiseptic cleaning lotions and ointments and creams and things, that a lot of people probably use at home.
MCGROUTHER
Yes, anything you might put in a wound or use to close a wound, it's very difficult to design a trial for this. And if you go back to Lord Lister, about 150 years ago, when antiseptics started, he used to spray carbolic, which is a very toxic acid, he sprayed an aerosol of this around the operating theatre. It was probably bad for the wounds and bad for the assistants but it was also bad for the bugs. Now we've stuck with antiseptics for a very long time but in fact if you put antiseptic into growing tissue it will actually kill a layer of cells in the tissue.
PORTER
But tap water - I mean tap water's not even sterile.
MCGROUTHER
Well tap water is pretty sterile in this country as it comes out the tap, I mean surgeons wash their hands in tap water. And there are very, very few bugs in it. So it's as near to being sterile as is necessary.
PORTER
So I mean the implications for people listening who might be treating minor cuts and grazes at home is that really antiseptics have fallen largely out of favour among doctors?
MCGROUTHER
I think there are two schools of thought - there are people who are moving towards the tap water and just making sure that a wound is adequately clean, that any dirt or lumps of tissue or anything loose comes out of the wound. And then there's still another school of thought that clings very religiously to antiseptics like iodine and products like that.
PORTER
Can you explain how glue works - we also heard Simon there talking about glue, that's a relatively new advance? It was just coming in when I was doing my training in hospital and I always thought that if you're putting glue into a wound that you're actually putting a foreign body in there that might inhibit the healing process. How does the scar tissue get through the glue?
MCGROUTHER
The principle of closing the wound whether we use glue or stitches or whatever it is to try and get the edges together, so that the healing process has the shortest possible distance to go and that way you get the least possible scarring. Now with the use of glue the ideal is to put the glue just on the surface, so that there's nothing between the wound edges that tissues have to grow through. But there is some evidence that you can make glue from proteins in the blood, this is being used in other countries, and this in a wound, such as let's say a wound in a nerve or in an internal structure, the body can grow through this glue. So I think we're probably looking to the future at having two sorts of glues - one that just seals the wound and another one that you can put in the wound that the body will grow through.
PORTER
What about infection - I mean that's probably the single biggest cause of delay in wound healing, you fall over and graze your knee, you're going to get bacteria in the wound, are they all bad?
MCGROUTHER
Bacteria are not all bad. There's now evidence that some bacteria in a wound may deter the growth of other more noxious bacteria. And there is science going on to try and work out what bacteria we might be putting in the wound. And I predict in the future we'll probably have some genetically engineered bacteria that we inoculate into a wound to keep the nasty ones out but I think that's a long way off.
PORTER
The NHS has a poor international record when it comes to hospital acquired infections - around 1 in 10 patients admitted to a British hospital pick up some sort of infection. Ali Ayres visited Salisbury District Hospital to find out what's being done to protect patients undergoing surgery.
AYRES
This is Britford Ward at Salisbury District Hospital and it's a busy general surgery ward, lots of patients being admitted today for various kinds of procedures. And I'm joined here by Philippa Potter, who's the associate director of nursing for the hospital. Philippa, how does someone contract a wound infection?
POTTER
A specific infection such as staphylococcus or streptococcus infections can be spread by skin contact, so a dirty hand for instance, or through droplets, so if you've got a sore throat, an infection in your throat, and cough and that can come out by droplet infection.
AYRES
Cutting the skin - even with surgical precision - will always leave a patient vulnerable to an infection at the site of the wound. Harmful bacteria might find their way in during the procedure itself, or soon afterwards before a scar has closed.
ACTUALITY
NURSE
I'm basically just going to go through some of the information that you need for actually after your operation about your wound care. Okay?
AYRES
Clifford Young is being admitted to Britford Ward for a straightforward hernia repair. The length of hospital stays for surgical procedures has shortened dramatically in the last 20 years and like most of the patients admitted here, Clifford will be home again within 24 hours. So nurses explain to him how he can look after his scars by himself.
ACTUALITY
NURSE
So what you should have are just three, perhaps four, tiny little holes through your belly button and just below. And they're about an inch long maximum. And when you come back to me from the theatre all you'll have on them is a little bit of a dry dressing. Sometimes you get a little bit of blood coming on to it, but that's fairly normal.
AYRES
The good news is that the majority of surgical wounds do heal normally at home and surgeons take care to make sure that's the case.
RANOBOLDO
I'm Charles Ranoboldo and I'm a general and vascular surgeon based here in Salisbury. Everything that's done in an operating theatre is designed to minimise the risk of wound infection. At a very simple level of course it's down to the preparation of the skin, we've now stopped shaving patients before they go to theatre because we know that the chance of them getting a wound infection if they're shaved the day before or even just a few hours before increases the risk simply because of minor abrasions and cuts that occur on the skin with a steel razor. We prepare the skin, using one of a number of solutions which cleanse the skin and also reduce the bacterial counts. We increasingly use what are known as incised drapes, rather like cling film, which are stuck to the skin before the operation starts. And we then operate through that by cutting through the film and the skin in one clean action, leaving the plastic sticking to the rest of the surrounding skin to prevent cross contamination. And we then aim to minimise the trauma to the tissues as we're operating. And that means gentle technique, avoiding using overly forceful retractors, avoiding causing too much damage to the tissues, particularly as we're controlling bleeding blood vessels.
AYRES
On the wards too, efforts are being made to reduce the number of infections. Hand hygiene campaigns are underway in many hospitals. And at Salisbury a new programme of identifying patients most at risk of infection, due to poor nutrition or an underlying medical condition, has just been started. I asked associate director of nursing Philippa Potter if patients are more wary of wound infections now that conditions like MRSA are making the news.
POTTER
I think so, because its so closely related to infection prevention and control which the public will be much more aware of these days. And we work closely with the health protection agency and have a very clear programme of surveillance - that is looking at what infections we have, their prevalence, i.e. how common they are, and their spread.
AYRES
Monitoring is a first step in reducing the numbers of wound infections and surveillance of individual procedures is taking place on Britford Ward. But with such rapid discharge most wound infections are diagnosed and treated out of sight of the hospital. Charles Ranoboldo admits few surgeons have an accurate picture of how many of their patients are affected.
RANOBOLDO
We know that it's much higher than the figures that we see just simply for hospital infection rates. And the reason for that is that most infections occur in the community and they're looked after by the patients' general practitioners and the patient never comes back to look the surgeon in the eye and tell them what a terrible time they had. The incidence of wound infections is probably almost ten times higher than the figures which are observed within hospital practice.
AYRES
That's a problem isn't it, I mean wouldn't you rather know how many of your patients have had to go to their GP, even if they've just had a week of penicillin or something?
RANOBOLDO
I think that's right. We don't have the - we don't have the joined up information systems at present to allow the hospital practitioners to see the whole of their practice. If surgeons were able to see more clearly for themselves the out turn of their work they would have a more powerful reason to be concerned about what happens in the operating theatre in the first place. But many surgeons today still haven't got a clear idea as to what happens to their patients once they leave the hospital.
AYRES
Many wound infections clear up with a simple course of antibiotics, but some can turn into more serious long-running problems. Philippa Potter encourages patients to be observant.
POTTER
A person would need to be looking out for redness, swelling, lack of mobility say in a joint and perhaps a smell. So they might start to notice themselves that something's wrong. Early detection is the key really and so the advice I would give to any patients is to see their GP as soon as possible, as soon as they have a worry about it.
RANOBOLDO
Surgical wounds do take quite a period to heal and although the stitches may not be visible or may have been removed the wound is still continuing to heal and will do so for many months in fact. And that needs to be respected by the patient and that's an issue for patient education as much as anything.
PORTER
Surgeon Charles Ranoboldo ending that report by Ali Ayres.
Gus, infection must be a particular problem in your field, in plastics and reconstructive surgery, not because the patients are dirty but because obviously the sort of surgery you're doing is very sensitive and if the wound doesn't heal properly you get a very poor result.
MCGROUTHER
Yes, an infected wound will leave a worse scar. But bacteria are only one factor in wound infection, the other things that are important is the delicacy of the surgery, if it's rough surgery - and this has been known for hundreds of years - then you bruise the tissues and that tissue is much more likely to get infected. And the other thing that's a big problem is the retention of fluid in a wound. So although there is a tendency to try and close all wounds up tightly, in most cases you're better to actually leave a few holes or even put in a drain so that no fluid can collect ...
PORTER
I was going to ask you about that because I mean your area one thing you really want to avoid is scarring - if you're removing something nasty from somebody's face you want the best cosmetic result possible. I was going to ask you how you're achieving these so-called invisible scars - is it because you're better surgeons or is it because you take more care, are you more gentle with the tissue?
MCGROUTHER
Well there are a number of tricks. I hope we take more care and we're more gentle. It's very important to stop bleeding before the wound is shut and we use little electrical coagulators to do that. If it's a situation where we can't stop all the bleeding we need to make sure blood doesn't collect in the wound because that will give infection. So we could use something like a drain to stop blood collecting or occasionally on a scalp, for example, we might use a tight bandage, but we tend not to use tight bandages very much nowadays.
PORTER
Are you using different needles or suture materials from other surgeons?
MCGROUTHER
I think plastic surgeons have introduced fine instrumentation, very fine needles and needle holders and instruments for gripping the tissue, we tend to lift the edge of the wound with a fine hook, rather than grabbing it with a big clamp. But other surgeons have adopted our tricks and I would think that the standard level of closure of a wound in an A&E department now is immensely better than it was 20 years ago because they've learned from techniques developed in the operating theatre.
PORTER
Why do some people scar more than others and can you predict where you're likely to run into trouble?
MCGROUTHER
You can spot certain people who will scar badly. Young people scar more and children scar a lot. And certain wounds scar badly, like burns. But there is also an individual variation - two people having the same operation might end up with a very different scar. And there are certain types of abnormal scarring - there's a type we call a keloid scar, which is very common in Afro-Caribbeans and is also common in people of Viking extraction. And it seems that certain genetic groups seem to be slightly more susceptible to it, although you find it in every country in the world. And that is a situation where the scar just keeps growing, so that the surgeon can do a nice job but the scar continues to grow for a long time, it may eventually settle down, in some people it can go on for many years.
PORTER
And these keloid scars you often - I mean see pictures of the African tribal scars, where people wear them on their face, you often see keloid there - the big lumps.
MCGROUTHER
Yes I think the reasons why Afro-Caribbeans possibly get this more often is that over centuries they've selected the gene for this because it was a respected thing, in groups who have used scarification as a form of decoration.
PORTER
It was more obvious ...
MCGROUTHER
It's more obvious and it's more common.
PORTER
What about lifestyle factors? Do things like smoking, for instance, affect your wound healing?
MCGROUTHER
There's some indirect evidence that smoking gives you more wound complications, like wound infection, but it's not good evidence, it's the sort of area where you can't really mount a good trial, it's very difficult to standardise the amount that somebody smokes and to exclude other factors.
PORTER
Is diet a consideration for you when you're getting people in for surgery, if you're planning a big operation on somebody?
MCGROUTHER
Diet's important in a big operation, if somebody has a big cancer operation it's important to get their nutrition up before you start. Generally for the run of the mill operations most people are fairly well nourished.
PORTER
Well Catherine Collins is chief dietician at St George's Hospital in London and I asked her what nutritional considerations are important after surgery.
COLLINS
After an operation the most important thing is hydration, you can tell if you're well hydrated if you're having to go and wee three or four times a day, if you don't go and wee three or four times you really are a bit on the dry side. In order for a wound to heal you've got to supply blood to it and the blood carries the nutrients, it carries the oxygen, it carries the white cells to fight infection and if you're dehydrated on a hospital ward you really will have problems getting the wound healing process started. And in addition eating little and often - the light diet which often is recommended by surgeons is usually a lowish fat diet because when you've got pain control, when you've been sedated for anaesthetic, your appetite is affected, you don't feel hungry. So having things to drink like milk or the supplement drinks, eating small amounts of food regularly, will help get you back on the road to recovery because food is absolutely key to recovery along with management of the wound and without adequate food intake the wounds will take longer to heal and it puts you at greater risk of hospital acquired infections and the like.
PORTER
Infection is the single most important cause of delayed healing after an operation, and good nutrition can help protect patients.
COLLINS
Infection risk depends on a number of things. From a nutritional point of view your protein intake affects your immune response. If you eat a very low protein diet, you've got very poor appetite, your immune system is compromised, so any infection in the wound will take longer to recover from. If you eat a good diet, a varied diet with plenty of protein and calories from other sources then you'll have a healthy immune system and that can try and override any infection in the wound that you may develop.
PORTER
But what about dietary supplements like vitamin C - widely promoted as boosting wound healing?
COLLINS
Taking single nutrient supplements are not really a good idea. And by that we mean, for example, taking a high dose vitamin C or a high dose zinc supplement, they certainly haven't been shown to improve the rate at which you heal your wounds. And in fact they could be detrimental. High levels of vitamin C can give some people the runs, high levels of zinc will lead to problems with the absorption of calcium and iron and anaemia, resulting from iron loss, is a major cause of problems in wound care.
PORTER
Dietician Catherine Collins who, like most hospital based dieticians, only advocates supplements for the majority of patients recovering from surgery if they are taken in a general mineral and vitamin preparation, that contains no more than the recommended daily amount of each ingredient. There are, of course, exceptions to this - and the dietician should intervene in cases where more aggressive dietary manipulation is required.
Gus - we've heard about glue and staples - both relatively recent innovations in wound closure - what's on the horizon?
MCGROUTHER
We'd like wounds to heal without scars and to do this we need to go back and look at the tadpole - how does it regenerate a part of its body? And by doing that we understand the mechanisms by which a wound heals, it's all done with the little cells in the tissues signalling to one another with little protein molecules, which we call growth factors, and we can now add growth factors or take them away or block their effect and by doing this we can alter the way in which a wound heals. So that we can perhaps remove some of the signals that are moving towards scarring and try and move more towards the regenerative pathway used by the tadpole.
PORTER
It goes back to my original question though, right at the beginning of the programme, I asked you how do we know what works because there are so many variables in people who are having surgical operations, how do you know that by manipulating these growth factors that that patient's actually got better than they would have if they'd not had the procedure done?
MCGROUTHER
Well we have trials underway just now where we're going to enormous lengths to quantitate the amount of scarring using things like photography and ultrasound, so that we can measure the scar objectively. And then we can alter the growth factor environment and measure whether they get less scar. Now to do this effectively you really need to have to two wounds in one patient because everybody's a bit different. And so we're doing that ...
PORTER
How are you doing that?
MCGROUTHER
Well we have people who are having operations where they have perhaps more than one procedure done at once and we can treat one wound, not the other, measure the scar ...
PORTER
Because it is difficult to get people to volunteer to be cut up and stitched back up again.
MCGROUTHER
Actually it's not, it's fascinating - we're doing volunteer studies. We've done volunteer wounds on hundreds of patients because people want to move this knowledge forward. And when we've advertised for volunteers we've had huge numbers of people coming forward. So we're now designing trials on - some of them are designed on people who need an operation anyway and some are designed on people on whom we make a very small wound - such as a scratch wound - but we can then analyse what happens.
PORTER
And what other things might we expect to see? I mean we're still some way off using - I'm thinking of the Star Trek type analogy where you have the fancy laser that sort of unzips the skin and zips it back up again - chance would be a fine thing.
MCGROUTHER
Well it's interesting, again if you go back to the tadpole, we have the same genes as the tadpole, we just have an awful lot more. So I think we will get round to a stage of being able to regenerate parts of the body. I think we'll have tissue regeneration, we'll have tissue engineering where we grow spare parts in the laboratory. And I think in terms of closure of the wound we probably will have machines that zip up the skin and possibly glue it shut and perhaps inject into the surface underneath a cocktail of chemicals that will allow the body to heal with less scarring.
PORTER
Professor Gus McGrouther thank you very much.
I'll be leaving the studio for next week's programme, which comes from the Moorfield's Eye Hospital, celebrating its bicentennial anniversary this year. I'll be discovery why it's so important for people with diabetes to have regular eye checks, and what leading eye specialists think of laser surgery for long and short sightedness - and if it really is that good, why do so many of the surgeons who do it still wear glasses?
ENDS
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