222
The scientific basis of the management of injury, wounds, and ulcers
REPAIR AFTER RESECTION
N A Matheson chM FRCS Consultant Surgeon, South Grampian (Aberdeen) Health District
Introduction Although the ways of intestinal surgery appear set and stable, recent years have seen the development of new attitudes that will in time mo,dify current practice and sulbtend improved standards. First, the emergency surgery of colonic lesions presenting with sepsis or obstruction is now more aggressive than before and the place of traditional staged procedures is called in question. Inquiry into the effect of changing attitudes in an audit of results in colonic and rectal cancer in the United Kingdomn by Fielding' has revealed very large differences in morbidity and mortality between centres and that in some centres as many as 3070 of elective colonic or colorectal anastomoses break down with clinical evidence of dehiscence and that as many as 2070 of patients die. Secondly, the analytical work of the University Department of Surgery in Leeds under the direction of Professor Goligher has focused attention on the particular problems of colorectal anastomosis. Their observation2 that leakage, albeit subclinical, may be found in some 50'7o of coborectal anastomoses is fundamentally important and has become a workbench upon which improvement may possibly be crafted. Unjustified complacency in intestinal surgery is therefore being dispelled and problems that were hitherto undisclosed now present themselves for solution. Currently in-terest is focused on suture technique and on the possible advantages of single-layer anastomosis. The method of study is familiar and may be termed 'piecemeal scientific engineering'-the dissection of isolated fragments of the problem. Such a dissection has limitations and while it might conceivably lead to improvement in respect of the incidence of radiographic leakage in centres of excellence, it is unlikely to be the foundation for eradication of unacceptable morbidity and mortality elsewhere. Improved standards in large-bowel surgery are likely to depend on a more comprehensive approach.
Foundations for safety First, there are circumstances that set the scene for safety in anastomosis. There is evidence that the faecal-loaded colon cannot be safely anastomosed'. Thus colonic obstruction, be it acute or simply sufficient to interfere with thorough mechanical cleansing, is a contraindication to anastomosis unless the obstructed segment is to be removed, as in ascending or transverse colon lesions treated by right hemicolectomy or extended right hemicolectomy. In left-sided obstruction Hartmann's procedure fulfils the ideals of urgency in resection with delay in anastomosis, although the magnitude of the operation required to restore continuity is a disadvantage. The traditional staged procedure with preliminary colostomy to permit mechanical cleansing is no less sound in concept. The important principle is that a clean colon is a prerequisite for safe colorectal anastomosis and whole-gut irrigation appears to be the most effective, economical, and humane method of colonic preparation. Further, sepsis is inimical to safe colonic anastomosis35. In sepsis of colonic origin, from free or localised perforation, eradication of the source by exteriorisation or resection is now mandatory, but anastomosis should be avoided. The principle that resection and repair be regarded as two separate and independent exercises requires emphasis: aggression in resection but caution in anastomosis are the watchwords of sound judgment in colonic surgery that satisfy the principles of emergency surgical management and set the scene for safety in repair.
Philosophy of anastomotic technique The aim of anastomosis is clearly to hold the divided bowel ends accurately opposed without tension until healed. Currently sutures, although alien, remain the most applicable device for this. The sole function of sutures is to approximate tissue with minimal inter-
The scientific basis of the management of injury, wounds, and ulcers
ference in healing. There is evidence that every suture causes dissolution of collagen in its vicinity'. Further, the placement of a suture inevitably results in a degree of ischaemia in the immediately incorporated tissue. In addition, sutures induce a variable degree of cellular response which may delay collagen deposition. For these reasons it is rational to bury the minimum of foreign material in a healing wound and to use a synthetic material, of which braided polyamide is an example that handles well. If approximation may be achieved with one rather than two layers of sutures so much the better, and a single layer of sutures which bite into the submucosa but spare the mucosa is theoretically appealing and has the additional advantages of avoiding complete penetration of the gut wall and of simplicity.' For anatomical reasons this argument is inapplicable in the special case of the oesophagus. A continuous suture has attractions of simplicity and speed and is appropriate unless the sutured wound is required to lengthen. However, the rectum in particular is distensible and will inevitably become distended by flatus or faeces within days of operation. A colerectal anastomosis therefore requires to be extensile. It follows froim the mathematics elaborated by Jenkins' on wound lengthening that extension in a circumferential wound sutured continuously is possible only at the expense of compression and ischaemia of the tissue incorpoirated in the continuous suture. Interrupted sutures which spare a bridge of normal intervening tissue result in an anastomosis which is obviously elastic and distensible.
Further considerations After completion of the anastomosis there are further practical considerations that may prevent morbidity. Firstly, faecal contamination of the operation field is similar in effect to sepsis and although a minor degree of faecal contamination does not prohibit anastomosis, it logically requires lavage of the operation field using an antibiotic with an anaerobic spectrum of activity. There is now sound evidence to support antibiotic lavage in peritonitis8' 9, and its routine use after colonic anastomosis whether contamination is obvious or not makes sense.
223
Secondly, drainage of an anastomosis to make a track for escaping intestinal contents lacks purpose. If an anastomosis leaks, sepsis may be subclinical or localised and intervention unnecessary. Otherwise contamination may be generalised and demand reoperation. Drains appear irrelevant to these considerations although, if necessary, there is purpose in fine suction drains for 24-48 h to remove blood. Thirdly, a 'protective' colostomy made at the time of anastomosis is misnamed inasmuch as it does not appear to influence the incidence of dehiscence although it may minimise subsequent morbidity and mortality2' 10. Finally, neostigmine given to reverse relaxation after abdominal closure may be a factor in anastomotic dehiscence" and so long as such a possibility remains, this drug should probably be avoided. Hypothesis The attractive logic of single-layer anastomosis is supported by personal experience'2 and also by experimental evidence on luminal reduction, tissue strangulation, and anastomotic strength"-'7. Yet the results of recent controlled clinical trials to test the merit of single-layer techniques in colorectal anastomosis are conflicting'8 19. The particular single-layer serosubmucosal technique which we use"0 has not yet been subjected to, controlled trial, but although differences in suture technique and material may matter, it seems doubtful whether these are important. The results of anastomosis are multifactorial in origin and are to a large extent a matter of surgical attitude and performance which is difficult to analyse. The surgeon who treats a high proportion of his patienits by anterior resection may have a higher incidence of anastomotic dehiscence than he who in the anticipation of difficulty takes refuge in abdominoperineal excision. So will he who makes an anastomosis despite proximal faecal loading or pus in the pelvis. He whose dissection is bloody risks diminished colonic blood flow". He whose craftsmanship in cutting and sewing is short of perfect may expect similar results. The immediate outcome of surgery for colonic and rectal cancer varies enormously in the United Kingdom and much depends upon who does the operation', but it is doubtful whether
224
The scientific basis of the management of injury, wounds, and ulcers
variations are attributable to the minutiae of anastomotic technique. Anastomotic safety depends on the integration of many factors, of which sound judgment, meticulous preparation, sound technique, of which the single-layer serosubmucosal method using braided polyamide is an example, antibiotic lavage, and avoidance of anastomotic drains and of neostigmine form a personal creed. Although these are some of the more tangible aspects of safety in repair after resection they are not only elusive of study but may also be individually less important. Together they make a 'package deal' that might possibly lend itself to evaluation and to adoption.
References I Fielding, L P (1978) Personal communication. 2 Goligher, J C, Graham, N G, and De Dombal, F T (1970) British Journal of Surgery, 57, I09. 3 Rosenberg, I L, Graham, N G, De Dombal, F T, and Goligher, J C (I97I) British Journal of Surgery, 58, 266. 4 Hawley, P R (1970) Proceedings of the Royal Society of Medicine, 63, 752. 5 Debas, H T, and Thomson, F B Surgery, Gynecology and Obstetrics, I35, 747. 6 Adamsons, R J, Musco, F, and Enquist, I F (I965) Surgery, Gynecology and Obstretics, 12I, 1028.
7 Jenkins, T P N (1976) British Journal of Surgery, 63, 873. 8 Stewart, D J, and Matheson, N A (1978) British Journal of Surgery, 65, 54. 9 Stewart, D J, and Matheson, N A (1978) British Journal of Surgery, 65, 57. io Schrock, T R, Deveney, C W, and Dunphy, J E (I973) Annals of Surgery, I77, 5I3. ii Bell, C M A, and Lewis, C B (I968) British Medical Journal, 3, 587. I2 Matheson, N A, and Irving, A D (I975) British Journal of Surgery, 62, 239. I3 Halsted, W S (I887) American Journal of the Medical Sciences, 94, 436. I4 Hamilton, J E (I967) Annals of Surgery, i65, 917. I5 Letwin, E, Williams, H T G, and Harrison, R C (I967) Journal of the Royal College of Surgeons of Edinburgh, 12, I 2I. i6 Orr, N W M (I969) British Journal of Surgery, 56, 771. I7 McAdams, A J, Meikle, A G, and Taylor, J 0 (I970) American Journal of Surgery, I20, 546. i8 Everett, W G (I975) British Journal of Surgery, 62, 135.
I9 Goligher, J C, Lee, P W G, Simpkins, K C, and Lintott, D J (1977) British Journal of Surgery, 64, 609. 20 Matheson, N A, and Irving, A D (1976) Surgery, Gynecology and Obstetrics, 143, 619. 2I Gilmour, D G, Aitkenhead, A R, Hothersall, A P, and Ledingham, I McA British Journal of Surgery. In press.
CLOSURE OF THE ABDOMINAL WOUND Thomas T Irvin PhD chM FRcSEd Consultant Surgeon, Royal Devon and Exeter Hospital (Wonford), Exeter. Formerly Reader in Surgery, University Surgical Unit, Royal Infirmary, Sheffield
Introduction Almost every general surgeon who is practised in the art of abdominal wound suture might reasonably regard himself as an expert on the subject of abdominal wound healing. Yet the undeniable fact is that abdominal wound dehiscence and incisional hernia are familiar complications in modem surgical practice. Wound dehiscence or burst abdomen occurs in 1-3% of patients undergoing laparotomy through vertical incisions13 and incisional hernias occur in 4-I0% of cases35. These are serious complications and are not confined to cachectic patients or patients with advanced malignancy. In a recent study3 they occurred most frequently after elective operations for
peptic ulcer or gallstones and in another study' almost 50% of the patients who burst their abdominal wounds failed to survive this complication. It is understandable, therefore, that much research has been carried out on abdominal wound healing. It has been shown7 that various local and systemic factors may adversely affect the process of wound repair, but Dudley8 and Jenkins9 have suggested that abdominal wound disruption is essentially a mechanical problem. The abdominal wound is subjected to considerable mechanical forces. Coughing or any other factor which results, in abdominal distension will exert a lateral pull on the wound which may cause the suture material to cut
The scientific basis of the management of injury, wounds, and ulcers
REPAIR AFTER RESECTION
N A Matheson chM FRCS Consultant Surgeon, South Grampian (Aberdeen) Health District
Introduction Although the ways of intestinal surgery appear set and stable, recent years have seen the development of new attitudes that will in time mo,dify current practice and sulbtend improved standards. First, the emergency surgery of colonic lesions presenting with sepsis or obstruction is now more aggressive than before and the place of traditional staged procedures is called in question. Inquiry into the effect of changing attitudes in an audit of results in colonic and rectal cancer in the United Kingdomn by Fielding' has revealed very large differences in morbidity and mortality between centres and that in some centres as many as 3070 of elective colonic or colorectal anastomoses break down with clinical evidence of dehiscence and that as many as 2070 of patients die. Secondly, the analytical work of the University Department of Surgery in Leeds under the direction of Professor Goligher has focused attention on the particular problems of colorectal anastomosis. Their observation2 that leakage, albeit subclinical, may be found in some 50'7o of coborectal anastomoses is fundamentally important and has become a workbench upon which improvement may possibly be crafted. Unjustified complacency in intestinal surgery is therefore being dispelled and problems that were hitherto undisclosed now present themselves for solution. Currently in-terest is focused on suture technique and on the possible advantages of single-layer anastomosis. The method of study is familiar and may be termed 'piecemeal scientific engineering'-the dissection of isolated fragments of the problem. Such a dissection has limitations and while it might conceivably lead to improvement in respect of the incidence of radiographic leakage in centres of excellence, it is unlikely to be the foundation for eradication of unacceptable morbidity and mortality elsewhere. Improved standards in large-bowel surgery are likely to depend on a more comprehensive approach.
Foundations for safety First, there are circumstances that set the scene for safety in anastomosis. There is evidence that the faecal-loaded colon cannot be safely anastomosed'. Thus colonic obstruction, be it acute or simply sufficient to interfere with thorough mechanical cleansing, is a contraindication to anastomosis unless the obstructed segment is to be removed, as in ascending or transverse colon lesions treated by right hemicolectomy or extended right hemicolectomy. In left-sided obstruction Hartmann's procedure fulfils the ideals of urgency in resection with delay in anastomosis, although the magnitude of the operation required to restore continuity is a disadvantage. The traditional staged procedure with preliminary colostomy to permit mechanical cleansing is no less sound in concept. The important principle is that a clean colon is a prerequisite for safe colorectal anastomosis and whole-gut irrigation appears to be the most effective, economical, and humane method of colonic preparation. Further, sepsis is inimical to safe colonic anastomosis35. In sepsis of colonic origin, from free or localised perforation, eradication of the source by exteriorisation or resection is now mandatory, but anastomosis should be avoided. The principle that resection and repair be regarded as two separate and independent exercises requires emphasis: aggression in resection but caution in anastomosis are the watchwords of sound judgment in colonic surgery that satisfy the principles of emergency surgical management and set the scene for safety in repair.
Philosophy of anastomotic technique The aim of anastomosis is clearly to hold the divided bowel ends accurately opposed without tension until healed. Currently sutures, although alien, remain the most applicable device for this. The sole function of sutures is to approximate tissue with minimal inter-
The scientific basis of the management of injury, wounds, and ulcers
ference in healing. There is evidence that every suture causes dissolution of collagen in its vicinity'. Further, the placement of a suture inevitably results in a degree of ischaemia in the immediately incorporated tissue. In addition, sutures induce a variable degree of cellular response which may delay collagen deposition. For these reasons it is rational to bury the minimum of foreign material in a healing wound and to use a synthetic material, of which braided polyamide is an example that handles well. If approximation may be achieved with one rather than two layers of sutures so much the better, and a single layer of sutures which bite into the submucosa but spare the mucosa is theoretically appealing and has the additional advantages of avoiding complete penetration of the gut wall and of simplicity.' For anatomical reasons this argument is inapplicable in the special case of the oesophagus. A continuous suture has attractions of simplicity and speed and is appropriate unless the sutured wound is required to lengthen. However, the rectum in particular is distensible and will inevitably become distended by flatus or faeces within days of operation. A colerectal anastomosis therefore requires to be extensile. It follows froim the mathematics elaborated by Jenkins' on wound lengthening that extension in a circumferential wound sutured continuously is possible only at the expense of compression and ischaemia of the tissue incorpoirated in the continuous suture. Interrupted sutures which spare a bridge of normal intervening tissue result in an anastomosis which is obviously elastic and distensible.
Further considerations After completion of the anastomosis there are further practical considerations that may prevent morbidity. Firstly, faecal contamination of the operation field is similar in effect to sepsis and although a minor degree of faecal contamination does not prohibit anastomosis, it logically requires lavage of the operation field using an antibiotic with an anaerobic spectrum of activity. There is now sound evidence to support antibiotic lavage in peritonitis8' 9, and its routine use after colonic anastomosis whether contamination is obvious or not makes sense.
223
Secondly, drainage of an anastomosis to make a track for escaping intestinal contents lacks purpose. If an anastomosis leaks, sepsis may be subclinical or localised and intervention unnecessary. Otherwise contamination may be generalised and demand reoperation. Drains appear irrelevant to these considerations although, if necessary, there is purpose in fine suction drains for 24-48 h to remove blood. Thirdly, a 'protective' colostomy made at the time of anastomosis is misnamed inasmuch as it does not appear to influence the incidence of dehiscence although it may minimise subsequent morbidity and mortality2' 10. Finally, neostigmine given to reverse relaxation after abdominal closure may be a factor in anastomotic dehiscence" and so long as such a possibility remains, this drug should probably be avoided. Hypothesis The attractive logic of single-layer anastomosis is supported by personal experience'2 and also by experimental evidence on luminal reduction, tissue strangulation, and anastomotic strength"-'7. Yet the results of recent controlled clinical trials to test the merit of single-layer techniques in colorectal anastomosis are conflicting'8 19. The particular single-layer serosubmucosal technique which we use"0 has not yet been subjected to, controlled trial, but although differences in suture technique and material may matter, it seems doubtful whether these are important. The results of anastomosis are multifactorial in origin and are to a large extent a matter of surgical attitude and performance which is difficult to analyse. The surgeon who treats a high proportion of his patienits by anterior resection may have a higher incidence of anastomotic dehiscence than he who in the anticipation of difficulty takes refuge in abdominoperineal excision. So will he who makes an anastomosis despite proximal faecal loading or pus in the pelvis. He whose dissection is bloody risks diminished colonic blood flow". He whose craftsmanship in cutting and sewing is short of perfect may expect similar results. The immediate outcome of surgery for colonic and rectal cancer varies enormously in the United Kingdom and much depends upon who does the operation', but it is doubtful whether
224
The scientific basis of the management of injury, wounds, and ulcers
variations are attributable to the minutiae of anastomotic technique. Anastomotic safety depends on the integration of many factors, of which sound judgment, meticulous preparation, sound technique, of which the single-layer serosubmucosal method using braided polyamide is an example, antibiotic lavage, and avoidance of anastomotic drains and of neostigmine form a personal creed. Although these are some of the more tangible aspects of safety in repair after resection they are not only elusive of study but may also be individually less important. Together they make a 'package deal' that might possibly lend itself to evaluation and to adoption.
References I Fielding, L P (1978) Personal communication. 2 Goligher, J C, Graham, N G, and De Dombal, F T (1970) British Journal of Surgery, 57, I09. 3 Rosenberg, I L, Graham, N G, De Dombal, F T, and Goligher, J C (I97I) British Journal of Surgery, 58, 266. 4 Hawley, P R (1970) Proceedings of the Royal Society of Medicine, 63, 752. 5 Debas, H T, and Thomson, F B Surgery, Gynecology and Obstetrics, I35, 747. 6 Adamsons, R J, Musco, F, and Enquist, I F (I965) Surgery, Gynecology and Obstretics, 12I, 1028.
7 Jenkins, T P N (1976) British Journal of Surgery, 63, 873. 8 Stewart, D J, and Matheson, N A (1978) British Journal of Surgery, 65, 54. 9 Stewart, D J, and Matheson, N A (1978) British Journal of Surgery, 65, 57. io Schrock, T R, Deveney, C W, and Dunphy, J E (I973) Annals of Surgery, I77, 5I3. ii Bell, C M A, and Lewis, C B (I968) British Medical Journal, 3, 587. I2 Matheson, N A, and Irving, A D (I975) British Journal of Surgery, 62, 239. I3 Halsted, W S (I887) American Journal of the Medical Sciences, 94, 436. I4 Hamilton, J E (I967) Annals of Surgery, i65, 917. I5 Letwin, E, Williams, H T G, and Harrison, R C (I967) Journal of the Royal College of Surgeons of Edinburgh, 12, I 2I. i6 Orr, N W M (I969) British Journal of Surgery, 56, 771. I7 McAdams, A J, Meikle, A G, and Taylor, J 0 (I970) American Journal of Surgery, I20, 546. i8 Everett, W G (I975) British Journal of Surgery, 62, 135.
I9 Goligher, J C, Lee, P W G, Simpkins, K C, and Lintott, D J (1977) British Journal of Surgery, 64, 609. 20 Matheson, N A, and Irving, A D (1976) Surgery, Gynecology and Obstetrics, 143, 619. 2I Gilmour, D G, Aitkenhead, A R, Hothersall, A P, and Ledingham, I McA British Journal of Surgery. In press.
CLOSURE OF THE ABDOMINAL WOUND Thomas T Irvin PhD chM FRcSEd Consultant Surgeon, Royal Devon and Exeter Hospital (Wonford), Exeter. Formerly Reader in Surgery, University Surgical Unit, Royal Infirmary, Sheffield
Introduction Almost every general surgeon who is practised in the art of abdominal wound suture might reasonably regard himself as an expert on the subject of abdominal wound healing. Yet the undeniable fact is that abdominal wound dehiscence and incisional hernia are familiar complications in modem surgical practice. Wound dehiscence or burst abdomen occurs in 1-3% of patients undergoing laparotomy through vertical incisions13 and incisional hernias occur in 4-I0% of cases35. These are serious complications and are not confined to cachectic patients or patients with advanced malignancy. In a recent study3 they occurred most frequently after elective operations for
peptic ulcer or gallstones and in another study' almost 50% of the patients who burst their abdominal wounds failed to survive this complication. It is understandable, therefore, that much research has been carried out on abdominal wound healing. It has been shown7 that various local and systemic factors may adversely affect the process of wound repair, but Dudley8 and Jenkins9 have suggested that abdominal wound disruption is essentially a mechanical problem. The abdominal wound is subjected to considerable mechanical forces. Coughing or any other factor which results, in abdominal distension will exert a lateral pull on the wound which may cause the suture material to cut
