Annals of the Royal College of Surgeons of England (1993) vol. 75, 46-51

SURGICAL DEBATE

Colostomy is no longer appropriate in themanagement of uncomplicated large bowelobstruction: true of false?

Nicholas J Carty MS FRCSSurgical Registrar

Allan P Corder MS FRCSSenior Registrar

Royal South Hants Hospital, Southampton

Colin D Johnson MChir FRCSSenior Lecturer

University Surgical Unit, Southampton General Hospital, Southampton

Key words: Colon, surgery; Colon obstruction; Colostomy

Traditionally, large bowel obstruction has been managedwith staged procedures of initial transverse colostomy,followed by subsequent resection and finally closure ofthe colostomy. Concern that this approach might leavethe tumour to disseminate before resection led to the use

of primary resection, again with formation of a colos-tomy. It was thought unsafe to perform resection withprimary anastomosis in the presence of obstruction, butrecent series have questioned this dogma. Some authorshave argued that not only is it safe to perform resectionwith primary anastomosis, but that this approach carriesthe lowest overall risk of complications and death.Resection with primary anastomosis spares the patient a

colostomy and achieves all the aims of treatment with theshortest hospital stay.

This debate therefore addresses the question ofwhether there is any place for colostomy in the manage-ment of large bowel obstruction.

Should patients who have large bowel obstruction(without any evidence of perforation or peritonitis) bemanaged by staged procedures including formation of a

colostomy and its subsequent closure? This approachavoids anastomosis of obstructed, possibly oedematous

bowel with a potentially impaired blood supply. Alterna-tively, is it safe to perform a resection with primaryanastomosis in these circumstances?

The case for the motion

The case that colostomy is no longer appropriate in themanagement of uncomplicated large bowel obstructioncan be summarised as follows.

Firstly, a colostomy is an unpleasant burden to any

patient and there is general merit in avoiding thisprocedure when possible. In particular, many patientswith carcinoma of the colon have a poor prognosis and so

it is especially worthwhile to avoid colostomy in thesepatients. Secondly, resection with primary anastomosiscan be achieved with a lower risk of complications anddeath than either of the staged approaches to large bowelobstruction, and a patient who has resection with prim-ary anastomosis will spend the shortest time in hospital.Many patients who are intended to undergo stagedresection and colostomy closure never complete allstages, and fewer than one-half live with a closed colos-tomy, while in contrast the great majority of patientstreated by resection and primary anastomosis survivetreatment and never need a colostomy.The argument that a colostomy is unpleasant and

should be avoided if possible is self-evident and incontro-

Correspondence to: Mr C D Johnson, University Surgical Unit,F Level, Centre Block, Southampton General Hospital,Tremona Road, Southampton, SO1 6HU

Colostomy is no longer appropriate in uncomplicated large bowel obstruction

vertible. It must apply particularly to patients whose lifeexpectancy is short. Obstructing large bowel cancertends to be advanced; when diagnosed 35-44% areincurable (1-5). Even in patients with obstruction whoundergo resection for 'cure', the outcome is worse than inunobstructed cases (6). Few would disagree that success-ful resection and primary anastomosis provides betterpalliation than any primary treatment which involvescreation of a colostomy, even if ultimately the patientmay require a colostomy, as a result of tumour recur-rence in the pelvis for example. It is hard to imagine amore discouraging sequence of events than colostomy,resection, closure of colostomy, and subsequent forma-tion of another colostomy in the terminal stages of theillness.The controversy in this debate centres around the

relative mortality and morbidity of the two approaches.It is reasonable to suggest that the safest initial manage-ment of left-sided colonic obstruction should be trans-verse colostomy, followed by a staged resection. Thisapproach can relieve the obstruction with the minimumof surgical intervention. This view is supported by theresults of series where staged resection was the usualtreatment. The reported mortality rates are 4% to 12%(1,4,7-9). In series that report a higher mortality of 20%to 30% for staged resection (3,5,10,11) it must beconceded that the least well patients were selected for thisprocedure, while the fitter patients had primary resectionof the tumour. However, the use of a defunctioningcolostomy as part of a staged resection does have its owncomplications. Decompression alone is contraindicatedin perforated lesions, and perforation may be missed,with fatal consequences, especially if a limited laparo-tomy is performed (2,12). Furthermore, the stoma maybe placed distal to the obstruction in 5% of patients ormay fail to decompress the bowel for technical reasons in10% (2). Finally, the stoma itself is liable to complica-tions such as prolapse in 5% to 10% of patients, retrac-tion in about 5% and necrosis in about 2% of patients(2,10,12).

Similarly, primary resection of the tumour withdelayed anastomosis has been demonstrated to carry alow mortality rate (13,14). In a recent review of sevenseries including 122 patients, the use of Hartmann'sprocedure in obstruction has a combined mortality rateof 9% (15). However, tumour resection without anasto-mosis entails the stomal complications of necrosis andretraction (in up to 20% of patients) and stump sepsismay occur in about 10% of patients after Hartmann'soperation (16,17).

Although staged resection and primary resection withdelayed anastomosis can be safe initial options, themortality and morbidity of the further interventions thatthey necessarily imply must also be considered. Thestaged option requires tumour resection, which is asso-ciated with a 6% to 27% mortality rate (2,9-11,18,19)and then closure of the loop colostomy, to which largereviews attribute a 1% mortality rate (20,21). Reversal ofa Hartmann's operation can also be a major task andcarries an appreciable mortality rate of up to 20% (3).

These late events must be included in any considerationof different strategies.

In contrast, primary tumour resection with immediateanastomosis has the advantages of removing the tumourand restoring bowel continuity in a single operation, andeliminates the mortality and morbidity resulting from thestaged approaches, as well as avoiding the inconvenienceof a stoma. Segmental resection of left-sided lesions withimmediate anastomosis can be performed safely, pre-ceded by antegrade lavage (15,22-26), decompressionand extrusion of solid faeces (27-31) or with no particu-lar clearance of faecal matter (32). These 12 seriesreporting the results of primary resection with immediatecolocolic anastomosis include 291 patients with an overallmortality rate of only 8.4% and an anastomotic leakagerate of under 10% (Table I).An alternative strategy, which also avoids a colostomy,

is to extend the conventional wisdom of resection andanastomosis of right-sided lesions (6) to the left colon bythe performance of subtotal colectomy (17,33). In areview of 200 cases of subtotal colectomy for obstructionfrom 11 series, there was a combined mortality rate of 8%and a major morbidity rate of 8%, including a 3%incidence of anastomotic dehiscence. The major morbi-dity of primary resection and anastomosis is of similarorder to that of patients undergoing more conventionaltreatment (7,17,31).

Resection and primary anastomosis reduces theduration of hospital stay. In a prospective multicentrestudy, the overall mean stay was 40 days for stagedresection, and 20 for primary resection (6). Hospital stayafter resection and immediate anastomosis has beenreported as low as a mean of 7 days (25), and inmany other series patients are, on average, dischargedwithin 2 weeks (2,4,15,27). This alone represents aconvincing argument in favour of resection and primaryanastomosis.A further argument in favour of immediate resection is

that this offers the psychological advantage that thepatient knows the tumour has been removed, and doesnot have to face a major operation shortly after recover-ing from the emergency procedure.There were early claims that the 5-year survival was

better in patients treated by primary rather than bystaged resection (4,34). This was rationalised on the basisthat either the greater manipulation of tumour, or thegreater delay before definitive resection, adversely affec-ted the results of the staged protocol (2,35). These claimshave not been substantiated in subsequent reports(6,7,36) and therefore considerations of long-termprognosis are probably not relevant to the presentdebate.The final advantage of resection with primary anasto-

mosis is the better outcome in terms of avoidance ofpermanent colostomy. Of those patients who embark ona course of staged resection less than one-half emergewith their bowel continuity restored (2,10,17,19,31,34,37). This is because of disease progression, poorgeneral health, or the depredations of cumulative opera-tive mortality. Similarly, between one-third and two-

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48 N J Carty et al.

Table I. Data from series of primary resection and immediate anastomosis for left-sided colonicobstruction. The number of cases is expressed as a proportion of the total number of cases in thoseseries that are consecutive

Morbidity(%)

Mean age Mortality Leak WI Mean staySeries (reference) Bowel preparation Number (years) rate (%) % % (days)

Koruth et al. (15) Lavage 47/52 74 8.5 8.5 2.1 13.4Konishi et al. (26) Lavage 25 59 4 4Thompson et al. (23) Lavage 20 67 4 5 4 17Pollock et al. (24) Lavage 41/46 79 17 10* 5 12Naraynsingh andAriyanayagam (25) Lavage 30/32 3.3 0 6.7 7Dorudi et al. (26) Decompression 18/18 68 5.1 0 0 11Foster et al. (27) Lavage 15 76 7 13 0 18Valerio and Jones (28) Decompression 13 8 0Amsterdam andKrispin (29) Decompression 25 66 12 4 40 15

White and Macfie (30) Decompression 33/34 70 9 9 18 18Mealy et al. (31) Decompression 25/31 70 9.6 8 10 19Irving andScrimgeour (32) None 14 70 3 0 16 12

* Radiological leak

thirds of patients who have a Hartmann's procedure diewith their colostomy in situ (14,16,17,38). The largemajority of patients would undoubtedly not have had a

colostomy at all if they had been managed initially withan anastomosis.

Current practice in Southampton confirms that routinecolostomy is no longer appropriate in the management ofuncomplicated large bowel obstruction. In a 12-monthperiod, 30 patients were treated under the care of eightconsultant general surgeons. Most of the operations were

performed by Senior Registrars or Registrars. Details ofpathology and the operation performed are shown inTable II. A variety of approaches were used. Fourpatients with extensive intra-abdominal or pelvic malig-nancy were treated by loop colostomy alone and one illpatient with sigmoid volvulus had a colopexy. Theremaining 25 patients underwent resection. Two patients

had primary anastomosis with transverse colostomy andsix patients had an end colostomy in the left iliac fossa.One of these had unresected pelvic malignancy. Of 25patients undergoing primary resection, 17 avoided colos-tomy altogether. There was only one death within 30days of operation, in a patient with extensive malignancywho had a loop colostomy and died from metastaticdisease.Both techniques described for the avoidance of a

colostomy were used. Five patients underwent subtotalcolectomy with ileosigmoid anastomosis without majorcomplications. Twelve patients had resection and prim-ary anastomosis. Of these, five had on-table colonicwashout and in one a caecostomy tube was left in place.This was withdrawn before the patient was dischargedfrom hospital and the caecostomy closed. Previous exper-

ience has supported (15,22-26) the good results that can

Table II. Large bowel obstruction in Southampton July 1990-June 1991

Pathology Number Operation Comment

Carcinoma 26 ERHC + ISA (5)RPA (10) OTCW in four*R + C (7) Resection, anastomosis and transverse colostomy in two

Extensive tumour in oneColostomy (4) Extensive tumour in four

Diverticular 1 R+C (1)Sigmoid volvulus 3 RPA (2) OTCW in one

Colopexy (1)

ERHC, extended right hemicolectomy; ISA, ileosigmoid anastomosis; RPA, resection and primaryanastomosis; R + C, resection and colostomy; OTCW, on-table colonic washout; * caecostomy tube left inone patient

Colostomy is no longer appropriate in uncomplicated large bowel obstruction

be obtained with on-table colonic washout and primaryanastomosis after resection. The present figures showthat in selected cases it is possible to achieve successfulprimary anastomosis without bowel washout as suggestedin several recent publications (27-32).

In conclusion, the evidence presented above indicatesthat routine colostomy is outdated in the treatment oflarge bowel obstruction. It is clear that in modernpractice resection and primary anastomosis should be therule and colostomy should be reserved for particularcircumstances. Although some authors have found thatthe results of more complex surgery are poorer in thehands of trainees than consultants (6,18), this has beenrefuted by others (17,27,31), and this argument shouldnot be allowed to influence management.

The case against the motion

The arguments presented above are persuasive, butinsufficient to lead to the abandonment of colostomy aspart of the primary treatment of large bowel obstruction.This technique still has a place because, firstly, decom-pression of the obstructed colon by a transverse colos-tomy is a simple and quick procedure which is especiallyuseful in patients who are acutely ill from other causes.This procedure also does not demand great technicalexpertise and can, if necessary, be performed by arelatively inexperienced surgeon. Secondly, althoughthere have been suggestions that delay in resection of aprimary tumour might allow dissemination, experiencehas shown that staged resection has no adverse effect onoutcome. Thirdly, the use of extended right hemicolec-tomy has not been shown convincingly to be applicable toall obstructions in the left colon, especially those situatedmore distally. Fourthly, resection of the left colon withprimary anastomosis requires experience, enthusiasmand expertise for good results. If any of these features arenot available, then a less demanding procedure is appro-priate. Finally, some patients with obstruction of the leftcolon also have peritonitis or bowel perforation andresection with an anastomosis may well be inappropriatein these patients.A colostomy is clearly a major handicap, especially to

an elderly person (39). For this reason, a patient shouldnot be given a colostomy without careful consideration ofthe alternatives, but there are certainly good reasons foradopting this approach in many cases. For most sur-geons, treatment of left-sided colonic obstructioninvolves the formation of a colostomy (6).

Proximal decompression by a defunctioning transversecolostomy followed by a staged resection is the traditionalmethod of treatment and has the virtue of being theeasiest emergency procedure to perform (5). It wassuggested that this form of treatment followed by astaged resection of the tumour might give inferior survi-val to that produced by primary resection at the time oftreatment for obstruction (35). Evidence subsequentlyobtained from the Large Bowel Cancer Project and otherstudies has now contradicted this view and has shown

equivalent long-term survival for patients treated byprimary and staged resections (6,7,36). However, prim-ary resection requires greater technical expertise thanformation of a transverse colostomy, which would seemto be the technique of choice for an inexperiencedsurgeon who may have to deal with the emergencypresentation. A defunctioning colostomy will buy time toprepare the patient fully for an elective resection by anexperienced surgeon. There is a wide variation in themorbidity and mortality following initial defunctioningcolostomy. Mortality was approximately 17% in theLarge Bowel Cancer Project (6), but there were no deathsin a small series of severely ill patients reported byHuddy et al. (13). It is likely that some of the poor resultsobtained with initial defunctioning colostomy could beexplained by the fact that relatively inexperienced sur-geons are operating on relatively ill patients.

Although three-stage resection is a lengthy under-taking, it is premature to discard it from the surgicalarmamentarium. A rapid transverse colostomy and lapar-otomy performed by an expert is an appropriate methodof treatment of a patient with acute left colon obstructionand a coexisting acute medical illness. It should also benoted that local anaesthesia may be used to close atransverse colostomy.

If the patient is fit, and the surgeon is experienced,there is no doubt about the advantage of removing theprimary tumour at the same time as treating the obstruc-tion. Many surgeons feel, however, that it is safer tocreate a colostomy rather than risk leakage from ananastomosis (6). Primary resection and colostomy leadsto a decreased length of hospital stay compared withthose having staged resections (6,13), and some authorsfind a greater mortality associated with ileocolic andcolocolic anastomoses than with resection and colostomy(13).The great advantage of resection and colostomy is that

this approach combines tumour removal and avoidanceof the risk associated with an anastomosis.A further alternative to resection and primary colonic

anastomosis is resection of the tumour and primaryileocolic anastomosis using an extended right hemicolec-tomy, subtotal colectomy or even a total colectomy withan ileorectal anastomosis. This approach has been pro-posed by a number of authors; Hughes et al. (40) reportthe greatest number of cases (n = 52). It is claimed thatthe inevitable increase in bowel frequency improves withtime and is rarely a problem in the long term. Stephensonet al. (17) reported that in patients with rectosigmoidlesions treated in this way, mean stool frequency at 6months after resection was three times per day with arange of 2-4. It is questionable whether a mean dailystool frequency of 4, with variations around the mean,constitutes an acceptable result in a patient who may beelderly and frail. Although 10 series of patients treated inthis way are cited by Stephenson et al. (17), four of theseseries contain fewer than 10 patients and eight containfewer than 20. In two of the larger series in which sites ofobstruction are clearly specified (17,41), there appears tobe an excessive proportion of obstructions at the splenic

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50 N J Carty et al.

flexure, ie the most proximal part of the left colon, whencompared with the frequency at various sites of obstruc-tion recorded in the Large Bowel Cancer Project. Itseems likely that this treatment has been selected for themore proximal left colon lesions although this is notstated in the papers. Hughes et al. (40) give what appearsto be a fair view of the part to be played by this approachin left colon obstruction: "colectomy especially subtotal,is acceptable for the acutely obstructed colon, but istechnically demanding and demands experience inpatient selection". One could argue that it is alsodemanding of the patient, who must cope with the highvolume fluid stool which is the consequence of ileosig-moid anastomosis.

Is there any place for resection with primary colonicanastomosis as an emergency procedure? It has long beenheld that primary colocolic anastomosis following resec-tion of obstructing left colon carcinomas is followed by ahigh incidence of anastomotic leakage (5,37). Because ofthe fear of anastomotic leakage following obstructiontreated in this way, it has been proposed that the colonshould be cleaned and decompressed by means of intra-operative saline lavage (42). This technique, however,lengthens the operating time considerably and was origi-nally described in a series of only six patients (42) and itis noteworthy that even in series reporting this tech-nique, in which there has been a clear commitment tominimise the use of colostomies, a number of patientswith uncomplicated distal colonic obstruction have stillrequired an initial defunctioning colostomy (15).More recently, acceptable results have been reported

in two series in which distal colonic obstruction has beentreated by resection and primary anastomosis withoutcolonic lavage or defunctioning colostomy (27,30). Theimportance of colonic decompression was emphasised bythese authors. It should be noted, however, that all theseoperations were performed by a small number of sur-geons with a special interest in the avoidance of colosto-mies. In addition, these series almost certainly containedonly a small proportion of the total cases treated in theinstitutions concerned. It is doubtful whether such goodresults would be obtained by a global policy of distalcolon resection and primary anastomosis, in view of someof the poor results reported previously (37) and in somemore recent series (13,17).

In the Large Bowel Cancer Project, there was an 18%incidence of anastomotic leakage when a primary anasto-mosis was performed after a left colon resection forobstruction, compared with a 6% leak rate in non-obstructed cases (6). If the variations in elective left colonanastomotic leak rates found in the Large Bowel CancerProject are also found after left colon resection andanastomosis (and there is no reason to suppose that theywould not be), then unacceptable leak rates will beobtained in the hands of some surgeons. It seems likelythat good results for primary segmental resection andanastomosis for acute left colon obstruction depend onexperience, enthusiasm and expertise, and when any oneof these three requirements is lacking, the patient will bebetter served by a colostomy and staged resection.

In a proportion of patients, neoplastic colonic obstruc-tion is complicated by perforation. This is mainly aproblem of left-sided colonic lesions (5); in about two-thirds of the cases the perforation is adjacent to thetumour, while in the remainder it is usually in thecaecum (7). There are few data on the results of treat-ment of these patients. Those with a perforation at oradjacent to a left colon carcinoma are most likely to besuccessfully treated by resection of the tumour andperforation and the creation of a terminal colostomy.

In summary, colostomy in acute large bowel obstruc-tion is not a thing of the past because decompression bytransverse colostomy is simple, quick, applicable inpatients who are acutely ill from other causes, and doesnot demand great technical expertise. This approachconfers no long-term disadvantage in terms of tumourrecurrence. Extended right hemicolectomy has not con-vincingly been shown to be applicable to all left colonobstructions (especially the most distal tumours). Leftcolon resection and primary anastomosis requires exper-ience, enthusiasm and expertise for good results, and isunsafe in the absence of any one of these. Finally, a smallproportion of left colon obstructions are complicated byperforation.

Chairman's comments

The arguments set out above illustrate the difficulties oftrying to fix treatment policies for particular diagnosticgroups. The reality is that many factors must be con-sidered in the choice of treatment for each individual. Inpractice some patients will be suitable for treatment byresection with primary anastomosis, whereas some wouldbe more safely managed in the first instance with adefunctioning colostomy. While it may be technicallypossible to perform resection with primary anastomosis,some patients may have residual tumour in the pelvis andtherefore a high risk of recurrent obstruction fromtumour invasion of the anastomosis. Such patients mightbe best managed with a terminal colostomy.

Nevertheless, the weight of evidence is convincing,that it is inappropriate to perform a procedure whichleads to colostomy in all patients. The cumulative morta-lity and morbidity associated with a three-stage pro-cedure of colostomy, resection, and closure of colostomymean that this approach should only be used in patientswith severe acute medical illness in addition to obstruc-tion. Such patients may well undergo resection moresafely when the acute condition has been treated.

In the absence of complications such as perforation,and if the patient is in satisfactory condition, few woulddisagree that a primary resection is appropriate. Thisreduces hospital stay and deals with the primary cause ofthe obstruction. It is arguable that if the expertise isavailable to perform a resection, then it is also available toperform primary anastomosis. Debate will continue as tothe best way to achieve this, whether by subtotal colec-tomy and ileosigmoid anastomosis, primary colonic anas-tomosis after on-table colonic washout, or by anastomosis

Colostomy is no longer appropriate in uncomplicated large bowel obstruction 51

without bowel preparation. The success of these tech-niques in different series, however, is adequate proof thatfor the majority of patients with uncomplicated largebowel obstruction, a colostomy need not be considered.

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Received 13 February 1992