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Review
Management of bleeding and perforation after colonoscopy Expert Rev. Gastroenterol. Hepatol. 8(8), 963–972 (2014)
Konstantina D Paraskeva1‡ and Gregorios A Paspatis*2‡ 1 Department of Gastroenterology, Konstantopoulio General Hospital, Athens, 14233, Greece 2 Department of Gastroenterology, Benizelion General Hospital, Heraklion-Crete, 71409, Greece *Author for correspondence: Tel.: +30 281 036 8017 Fax: +30 281 036 8018 [email protected]
Bleeding is a relatively rare complication occurring mainly after snare polypectomy. The majority of cases can be managed successfully by endoscopic means leaving very few cases which will ultimately need an operation. Colonic perforation, on the other hand is a serious complication that requires intensive and careful management. Prompt recognition of the perforation during the procedure allows, in selected cases, immediate endoscopic closure with an uneventful and full recovery followed by close monitoring and surgical management in case of clinical deterioration. The criteria for the right selection of perforation cases amenable to endoscopic treatment do still need to be confirmed by prospective studies and further experience is required before a standard algorithm on the endoscopic management of perforations is developed. KEYWORDS: colonoscopy complication • endoscopic closure • perforation • postpolypectomy bleeding
‡
Authors contributed equally
Colonoscopy is considered globally the most reliable and easy to access endoscopic technique for detecting and manipulating mucosal colonic lesions. It is provided in highly different settings such as private practice endoscopy suites, hospital-based outpatient departments and tertiary referral centers, and performed by endoscopists with different experience and annual case volume. The complexity of the procedures performed depends on the available facilities and varies from purely diagnostic colonoscopy with or without basic polypectomy to complex endoscopic resections using endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) techniques. Colonoscopy is generally considered safe and well tolerated by the majority of patients, especially when no advanced procedures are conducted. Thus, complications are closely related to the complexity of colonoscopy, endoscopists’ experience and skills and facilities availability [1,2]. The incidence of major colonoscopy complications and 30-day outcome are set as quality indicators [3,4]. It is the endoscopist’s duty to assess the risk of complications in each specific case, to implement strategies to minimize the risk and last but not least once complications occur, to informahealthcare.com
10.1586/17474124.2014.925797
be able to recognize them and treat them accordingly. The endoscopist has to discuss with the patient and his family members the risk for complications, management options and potential consequences and informed consent should be obtained. A lexicon including standard terminology and a classification system of adverse events was proposed recently by the American Society of Gastrointestinal Endoscopy [5]. According to this, events that should be recorded as complications are the ones that result in an unscheduled admission; lengthening of hospital stay; a second unplanned endoscopic procedure; urgent intervention, including blood transfusion; urgent surgery; or lethal outcome. For grading the severity of complications, a scale from mild to major was used, depending on the duration of additional hospital stay and the need for transfusion or surgery. There are no large studies on the management of colonoscopy complications and no consensus algorithms are provided regarding the care of these patients due to the rarity of these events. Most of the data come from retrospective studies reporting on the incidence of complications and not focusing on the management of these cases. This review summarizes current literature and
Ó 2014 Informa UK Ltd
ISSN 1747-4124
963
Review
Paraskeva & Paspatis
expert consensus on the management of major colonoscopy complications. Management of bleeding complications of colonoscopy
Expert Review of Gastroenterology & Hepatology Downloaded from informahealthcare.com by University of Queensland on 03/13/15 For personal use only.
Risk assessment
Diagnostic colonoscopy is not associated with bleeding events unless cold biopsy samples are taken. The vast majority of these events are mild, although clinically significant bleeding cases have been reported, mainly in patients with underlying coagulopathy [1,6]. Bleeding occurs mainly after polypectomy either as an early (intraprocedural or within 24 h) or a late (>24 h) event. A small amount of bleeding, following polypectomy, that is controlled by endoscopic means or spontaneously ceased is common and is not considered as a complication [5]. Postpolypectomy bleeding (PPB) is defined as visible blood loss or melena occurring at any time up to 2 weeks following the procedure requiring transfusion, surgery or further endoscopic therapy [4]. Patient’s need for transfusion or surgery makes a bleeding episode major, otherwise it is characterized as minor. Intraprocedural bleeding is not considered as a complication unless it results in hospitalization, transfusion or operation [5]. Late-onset bleeding poses a more significant problem since it leads to urgent re-hospitalization or unplanned interventions. The lag time between baseline colonoscopy and the occurrence of bleeding may reach up to 2 weeks, and the patient may visit a different hospital without the initially treating endoscopist being notified about the referral. Delayed occurrence is the main reason why many complications remain underreported [7]. Endoscopic series suggest that the overall risk for PPB should be less than 1%, otherwise a review of polypectomy practices for inadequate performance detection should take place [3,8]. The reported incidence for PPB shows a great variation (0.3–6.2%), mainly due to differences in the definition of bleeding, the complexity of polyp cases and study set up [6,9–13]. Factors associated with the incidence of PPB are either related to polyp characteristics such as size, morphology and location of the polyp, or to the patient’s health status such as age >65 years, the presence of hypertension, renal disease and anticoagulant intake [14,15]. The size of the polyp has been reported as a major risk factor for PPB [10,14,16–19]. Polyps larger than 10 mm carry a 4.5-fold greater risk than smaller ones [10]. The risk for PPB is further increased by 9% for every additional millimeter of polyp size [19]. Right-side colon polyps, sessile morphology and polyps with thick stalks are also reported to be at an increased risk for PPB [11,20,21]. In general, the risk of adverse events after colonoscopy is positively correlated with polypectomy complexity. Adjusted risk of cumulative adverse events is gradually increasing with the use of cold forceps (1.21, 95% CI: 1.01–1.44), ablation (3.75, 95% CI: 2.97–4.72), hot forceps (5.63, 95% CI: 4.97– 6.39), snares (7.75, 95% CI: 6.95–8.64) or complex colonoscopy (8.83, 95% CI: 7.70–10.12) [1]. The use of cautery is associated with a 6–9-fold increased risk of PPB compared with cold techniques [1,22]. Nowadays, cold snare polypectomy 964
is considered as the gold standard technique for the removal of diminutive polyps [23]. The use of hot biopsy technique is no longer recommended. The type of the electrosurgical current applied for the polypectomy affects the incidence and the time of PPB occurrence. It has been found that the use of pure cut or blended current increases the risk of immediate PPB, while the use of pure coagulation current is associated with late-onset PPB [14,24]. Although most endoscopists use blended or pure coagulation current, some may choose to use pure cut waveforms for EMR and ESD [25]. The selection of the electrocautery waveform may be adjusted in a case-specific manner as it may be more practical to treat an early PPB event. Endoscopists should evaluate the risk of PPB or thermal injury for each individual case and engage the therapeutic option with the lowest risk, when clinically appropriate. Modern electrosurgical units with microprocessor control are associated with lower rates of PPB compared with the use of pure cut or coagulation current [15]. Clinical assessment
Most episodes of postcolonoscopy bleeding occur within 48 h, with only about 10% of the events occurring later on [9,10,26]. In about 40–60% of the cases, bleeding is self-limited without transfusion requirement [10,26,27]. However, some patients are readmitted with hemodynamic instability and multiple recurrent bloody bowel movements spaced at close intervals. (i.e., 30’–60’), indicating a likelihood of ongoing arterial hemorrhage. Patient management includes adequate volume resuscitation and transfusion of blood products as appropriate (target hemoglobin levels of 8–9 g/dl in most patients). Hypotension usually responds to fluid resuscitation. Ideally, patients should have normal clotting function, with an INR of less than 1.6 and platelet count of more than 50,000 to 70,000. Resuming anticoagulation within a week following polypectomy is an independent risk factor for delayed PPB (OR 5.2) [19]. The decision to reverse anticoagulation or consider platelet or fresh frozen plasma transfusion depends on the severity of the bleeding episode and should be weighed against patient’s risk for a thrombotic event. Urgent colonoscopy
Whether all patients presenting with rectal bleeding within 2–3 weeks following polypectomy need an urgent colonoscopy or clinical signs are available to safely spare unnecessary procedures is still under debate. No relative study has been conducted to answer this question with only experts’ opinion existing. The most common approach is to offer colonoscopy within 24 h to all patients presenting with bloody stools, similarly to gastroscopy being the gold standard in peptic ulcer bleeding [10,19]. Patients with no major stigmata (adherent clots, nonbleeding visible vessels and severe active bleeding) that are otherwise healthy can be quickly discharged. The prognostic value of endoscopic stigmata during urgent colonoscopy has not been adequately studied. Expert Rev. Gastroenterol. Hepatol. 8(8), (2014)
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Management of complications after colonoscopy
Another option is to perform urgent colonoscopy selectively in those with more than three bowel movements in 24 h and/or persistent hemodynamic instability or recurrent bleeding, and observe those who respond to initial resuscitation, always having in mind the risk for a poor outcome or the need of an urgent intervention [28]. Since bleeding is self limited in most cases, close clinical and hemodynamic monitoring might be enough for those who pass one or two semiformed black stools per day. An alternative clinical test for selecting patients suitable for urgent colonoscopy is to check the effluent for blood after providing colonic preparation [29]. Patients may receive colonic purge rapidly (usually a total of 4–6 l of polyethylene glycol solution within 3 h) after resuscitation and only proceed to colonoscopy if the effluent indicates ongoing bleeding. If the bloody effluent clears with preparation, and the patient is clinically stable, with minor comorbidities, withholding colonoscopy may be a reasonable option. Due to the cathartic properties of intraluminal blood, the use of bowel preparation depends on the endoscopist’s discretion and patient’s clinical condition and in cases of severe hematochezia someone may choose to go directly for urgent colonoscopy after patient resuscitation [30]. Since there are no validated therapeutic algorithms, the safest and the most efficacious approach remains to be proved in large-scale prospective, randomized trials. Using a decision model, it was calculated that a tandem colonoscopy for identification and treatment of PPB is beneficial in about 22% of patients, corresponding to a number needed to treat of 4.5 patients [31]. In elective colonoscopies on the following day in an otherwise stable patient, standard colonic preparation is the proper decision. The use of water pump in actively bleeding patients is strongly encouraged despite the absence of literature data. Choosing the proper endoscopic method
There are no strict rules stating which is the preferable endoscopic method for applying hemostasis in cases of PPB. Technique selection is based on endoscopist’s preference and device availability depending also on certain characteristics of the lesion and location of bleeding. The most commonly applied method is through the scope (TTS) clips, alone or in combination with a thermal method and/or adrenaline injection [6,21,32]. In cases of immediate massive PPB, the snare may be used to grasp the upper part of the remaining stalk, temporally stopping the bleeding and revealing the bleeding site more clearly. An endoloop or a clip can be subsequently applied [33]. The use of two endoscopes has been reported as an option to facilitate the procedure [34]. Injection of 1:10,000 diluted epinephrine into the site of bleeding is also used to reinforce instant hemostasis [35]. Bleeding that occurs after resection of a pedunculated polyp can be stopped mechanically by applying a clip or an endoloop [36–39]. A residual stalk must be present for the endoloop to remain in place. Endoscopic band ligation has also been used to treat PPB in cases of pedunculated or informahealthcare.com
Review
semipedunculated polyps [40–42]. In the cases of sessile polyps, recognition of the bleeding vessel allows hemostasis using clips or a thermal method. Urgent colonoscopy for PPB following EMR for large sessile polyps reveals a cautery ulcer covered with adherent clot or marginal bleeding. Removal of the blood clots by irrigation or with a cold snare guillotining technique allows the exposure of visible vessels that may be treated via endoscopic clipping. Bleeding from the margins is usually stopped with the application of a thermal method such as Argon Plasma Coagulation. The combination of endoclips with endoloop to close off the polypectomy ulcer, similar to the one used for perforation sites closure, has also been reported in successful treatment of late-onset PPB [43,44]. Caution is necessary during the application of hemostatic techniques as transmural injury from thermocoagulation and perforation during clipping have been reported among other complications [21,45]. Recently, an over-the-scope clip (OTSC; Ovesco Endoscopy AG, Tuebingen, Germany) has become available. This clip has a set up that works similarly to variceal band ligation system. Although the OTSC has been primarily used for the closure of perforations, it was also shown to be effective for PPB control refractory to other endoscopic modalities [46]. The advantage of using this device is that it can grasp a much wider area and larger volume of tissue than TTS clips. For ESD procedures, an excellent endoscopic tool to prevent or stop bleeding from the large submucosal vessels exposed during the procedure is the purposed designed coagulation forceps (Coagrasper; Olympus Medical Systems, Tokyo, Japan) [47]. Reported success rate of endoscopic treatment is very high (up to 90%) [48]. What if endoscopy fails to control bleeding?
Decisions on such, indeed, rare refractory cases should be based on local expertise and individual experience. Interventional radiologists can selectively embolize the feeding artery with absorbable gelatin sponge (Gelfoam) or coins [49]. Subtotal colectomy is always kept for patients with continuous bleeding that fails to be controlled by endoscopic means or embolization, when available [50,51]. Studies with PPB cases and their management are included in TABLE 1. Management of perforation after colonoscopy
A colonic perforation is usually defined as evidence of air, luminal contents or instrumentation outside the gastrointestinal tract [4]. A small perforation that is recognized during colonoscopy and sealed endoscopically without interfering with completion of the procedure or lead to a change in the management plan is considered as an event [5]. Grading the severity of a perforation is based on the prolongation of hospital stay and the need for surgery [5]. Intra- and/or postprocedural perforation that needs surgery is graded by definition as serious complication. The use of CO2 insufflation is routinely recommended in gastrointestinal endoscopy [52] and especially in cases with an iatrogenic perforation. If colonoscopy is undertaken under 965
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Table 1. Studies with postpolypectomy bleeding cases and their management. Ref.
Study (year)
Type of study
Bleeding cases (number of patients)
Endoscopic treatment (number of patients)
Angiography and embolization (number of patients)
Surgery to control bleeding (number of patients)
Heldwein et al. (2005)
Prospective
36
33
0
3
[11]
Sorbi et al. (2000)
Retrospective
83
80
1
2
[90]
Parra-Blanco et al. (2000)
Retrospective
63
62
0
0
[32]
Paspatis et al. (2008)
Retrospective
80
79
0
1
[6]
Singh et al. (2009)
Retrospective
21
7
0
2
[26]
Yousfi et al. (2004)
Case control
81
51
1
2
[27]
Burgess et al. (2014)
Prospective
62
21
1
2
[13]
room air and a perforation occurs, switch to CO2 insufflator should ideally be performed, if available (FIGURE 1). Risk assessment: causes of perforation
Intraprocedural perforation during diagnostic colonoscopy is extremely rare and occurs as a result of mechanical factors. It may occur by sideway pressure of a formed loop, and even more uncommonly because of a direct scope trauma or when taking biopsies from a distended cecal wall in an elderly patient. Preventive measures for this type of perforations include engaging the shortening technique of colonoscopy and avoiding high-risk maneuvers such as ‘pushing through’ or ‘sliding by’ or taking biopsies from a distended cecum. Patients with signs of colonic inflammation are also more likely to have a perforation. Preexisting conditions associated with an increased risk include acute colitis, a tumor or diverticula-based stricture, a fixed loop due to adhesions, prior radiation therapy and therapeutic procedures such as endoscopic resection and stenosis dilatation. The most common site of perforation is the sigmoid colon and the rectosigmoid junction (70%) [6,53]. Most commonly, perforations are induced by therapeutic interventions such as polypectomy with electrocautery application. This is either due to thermal injury beyond the submucosa or due to full thickness cut with the snare during standard polypectomy and EMR, or with the knife during ESD. Highdensity or prolonged current application can cause full thickness burn of the bowel wall. The right side of the colon is by far the most frequently reported site of perforation after polypectomy due to its thinner wall and the relative complexity in removing proximal lesions. The reported incidence of perforation in published series including diagnostic colonoscopies ranges from 0.016 to 0.2% and up to 1.1% for conventional polypectomy [6,11,54–57]. For more advanced therapeutic techniques, such as colonic ESD, incidence of perforation can be up to 5%, depending on the lesion morphology and location and the endoscopist’s skills [58]. However, recent data have shown perforation rates in colorectal ESD as low as 1.6% [59]. Corresponding rate of perforation during colonic EMR is 1.3% [60]. 966
It has been suggested that perforation rates greater than 1 in 500 for all colonoscopies or 1 in 1000 for screening colonoscopies should prompt evaluation of endoscopic practices [3]. Preventive measures include submucosal injection, although its efficiency in limiting the depth of thermal injury has only been proven in animal models. Today it is performed by about 80% of practicing clinical gastroenterologists for the piecemeal removal of large sessile lesions, particularly those located in the right colon and for ESD technique [61]. Clinical presentation
Perforations recognized during the procedure range from 25 to 60%, depending on the type of the therapeutic intervention performed and the endoscopist’s awareness [11,62]. Direct endoscopic recognition of a perforation forms a favorable scenario in which diagnosis is achieved before the patient develops any symptoms, and the options for either endoscopic on site repair or urgent surgery is on the table (FIGURE 1). Clinical suspicion of a perforation that is not endoscopically apparent should be raised on the presence of unremitting pain during or immediately after the colonoscopy and abdominal distension accompanied with patients’ inability to expel the air. Clinical deterioration within hours after colonoscopy requires radiological assessment and surgical review (FIGURE 2). This is often the case of a perforation during diagnostic colonoscopy because of the large size of the bowel defect created in these cases [63]. The majority of perforations present within 24 h [64]. Only a few cases may develop symptoms after that period mainly due to the formation of a coagulation eschar that is necrotized and drops in up to 2–3 days [64]. There are few reports of small perforations covered with omentum that remain silent and diagnosed with a delay of up to 14 days [65]. Clinical status and symptoms in postpolypectomy perforations are related to the severity of induced tissue injury. This ranges from a transient transmural burn without frank perforation (postpolypectomy coagulation syndrome), to perforations sealed by omentum and expand to free perforation with extensive leakage of bowel content and induction of diffuse peritonitis. Expert Rev. Gastroenterol. Hepatol. 8(8), (2014)
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Management of complications after colonoscopy
Review
Postpolypectomy syndrome (PPS) Intra-procedural expresses symptoms that reflect irritation recognition of the overlying serosa. PPS presents with localized pain, low fever and mild leukocytosis and its discriminating features Switch to CO2 over true perforation is the lack of severe (if available) symptoms and of free intraperitoneal or subdiaphragmatic air. The diagnosis of PPS may be misleading, therefore Endoscopic closure Endoscopic closure patients need very close follow-up due to feasible impossible the natural course of the syndrome, which either subsides with conservative treatment or leads to a frank perforation. Clinical deterioration Patient Surgery The incidence of PPS seems to be higher (sepsis signs, peritonitis) clinically stable at present due to the increasing application of advanced endoscopic polypectomy techniques. Especially after colon ESD of Conservative large polyps in sites other than the rectomanagement sigmoid, the risk of PPS may be up to 40.2% [66]. Figure 1. Algorithm for the management of intraprocedural recognized colonic A small perforation is usually covered perforations. with intestinal creeping fat and omentum. The patient suffers from localized pain and tenderness, accompanied by free air detected in and efficient and furthermore allows continuing the procedure abdominal x-rays and CT scan, but without signs of sepsis. In such as ESD. Studies on endoscopic closure of iatrogenic perfothese cases, 24 h of close clinical follow-up is mandatory. rations were initially conducted in porcine models followed by Rapid patient improvement favors conservative treatment while retrospective reports of clinical outcomes. Clips were shown to clinical deterioration prompts surgical intervention. In clinical produce a successful approximation of mucosa and submucosa practice, this decision may be a real dilemma in selected layers, while apposition of muscularis propria and serosa are not possible because of the superficial clipping. This partial situations. The time of recognition of the perforation followed by effec- thickness approximation has been shown to be effective and tive management is very important for the outcome. Data sufficient for the healing of perforation in animal models [74]. show that when the perforation was recognized within 24 h the mortality was very low, while a delay in recognition of more than 24 h after colonoscopy increased mortality up to Late diagnosis (>4 h post procedure) 66% [67]. Endoscopic management of perforations
Several case series report on the feasibility of conservative treatment of colonic perforation (TABLE 2) [11,68–71]. No prospective studies exist and no sufficient data to make clear recommendations on the indications of the endoscopic treatment of perforation. Endoscopic repair of perforation prerequisites that the damage is recognized during the endoscopy, the colon is clean to prevent leakage of bowel content outside the bowel and complete closure of the gap is achieved in order to reduce the risk of peritonitis. Occasionally, a perforation is diagnosed postprocedurally and if preparation is still adequate (within 4 h after the procedure) endoscopic therapy may also be considered [72,73]. The TTS clips Quickclip2 and EZ (Olympus Medical Systems, Tokyo, Japan); Resolution Clip (Boston Scientific, Natick, MA, USA); Instinct Endoscopic Hemoclip (Cook Medical, Winston–Salem, NC, USA) are currently the standard tools for sealing acute perforations. Their use is simple, fast informahealthcare.com
Stable clinical condition, + CT: no fluid collections
Unstable clinical condition, ± CT: fluid collections
Conservative management
Deterioration of clinical condition (sepsis signs, peritonitis)
Surgery
Figure 2. Algorithm for the management of late recognized colonic perforations.
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Table 2. Series of endoscopic closure of iatrogenic colonic perforations. Ref.
Study (year)
Type of study
Perforations (number of patients)
Initial endoscopic closure (number of patients)
Method
Successful endoscopic closure (number of patients)
Transferred to surgery out of clipped cases (number of patients)
Cho et al. (2012)
Retrospective multicenter
32
29
TTS clip
22
7
[76]
Magdeburg et al. (2013)
Retrospective
105
71
TTS clip
60
11
[91]
Voermans et al. (2012)
Prospective multicenter
13
13
OTSC
12
1
[83]
Kim et al. (2013)
Retrospective
27
16
TTS clip
13
3
[92]
Gubler (2012)
Case series
9
9
OTSC
6
3
[93]
OTSC: Over-the-scope clip; TTS: Through the scope.
Endoscopic clip closure however demonstrates certain limitations. It may be very difficult to succeed and verify the complete sealing of the perforation. The open prongs of the clip should reach and bridge the edges of the defect and this is not always feasible, especially in defects larger than 2 cm or round in shape or having reverted edges. Efforts to apply the clips may take time during which air and liquid luminal contents may leak into the peritoneal cavity. Technical advice and maneuvers to enhance successful clip closure have been recently published [75]. If clip closure is incomplete or the clips detach early, minor leakage can develop producing ambiguous symptoms and surgery may be delayed beyond optimal period. Perforation cases that undergo surgery after failure of endoscopic closure may have peritoneal abscess formation and fistula and might need aggressive surgical treatment including colon resection with diversion [76]. In expert centers performing ESD, while the perforation rate is higher and therefore endoscopists are alert for a possible deeper layer dissection, endoscopic closure is more frequently attempted and successfully applied. This type of perforations is usually less than 10 mm in size and its immediate recognition is eased by the use of indigo carmine dye of the muscularis propria and the high definition vision [77]. In the cases where the noncolored muscularis propria is visible in the base of the polypectomy ulcer like a target, early endoscopic treatment is warranted since this is a sign of deeper burn and potential perforation. Recognition of the so-called ‘target sign’ allows prompt endoscopic diagnosis and treatment sparing the need for prolonged medical management or surgical intervention [78]. Successful endoscopic closure of colon perforation after failure of TTS clip placement has been achieved with band ligation [79,80]. In these cases, a gastroscope is used to fit with the band ligator, and the perforation site is suctioned into the band ligator cup, resulting in the closure of the perforation. For larger defects, TTS clips may be used in combination with a detachable snare (Endoloop-Olympus Medical Systems, Tokyo), whereas the clips are placed around the circumference of the perforation and lassoed together with the Endoloop [81]. 968
Another technique described for large defects closure is the omental patch technique first applied on large perforations after gastric EMR and ESD [79]. It is based on the principle of pulling the omentum when visible, through the defect and clip it with the edges of the perforation. Recently, the OTSC has shown impressive results on the endoscopic closure of colonic perforations and fistulae [46,82]. The OTSC performs full thickness closure of gaps up to 20 mm in size. It also provides the possibility of tissue approximation with the use of a grasping device and retraction of the defect into the OTSC cap. Small perforations (
Review
Management of bleeding and perforation after colonoscopy Expert Rev. Gastroenterol. Hepatol. 8(8), 963–972 (2014)
Konstantina D Paraskeva1‡ and Gregorios A Paspatis*2‡ 1 Department of Gastroenterology, Konstantopoulio General Hospital, Athens, 14233, Greece 2 Department of Gastroenterology, Benizelion General Hospital, Heraklion-Crete, 71409, Greece *Author for correspondence: Tel.: +30 281 036 8017 Fax: +30 281 036 8018 [email protected]
Bleeding is a relatively rare complication occurring mainly after snare polypectomy. The majority of cases can be managed successfully by endoscopic means leaving very few cases which will ultimately need an operation. Colonic perforation, on the other hand is a serious complication that requires intensive and careful management. Prompt recognition of the perforation during the procedure allows, in selected cases, immediate endoscopic closure with an uneventful and full recovery followed by close monitoring and surgical management in case of clinical deterioration. The criteria for the right selection of perforation cases amenable to endoscopic treatment do still need to be confirmed by prospective studies and further experience is required before a standard algorithm on the endoscopic management of perforations is developed. KEYWORDS: colonoscopy complication • endoscopic closure • perforation • postpolypectomy bleeding
‡
Authors contributed equally
Colonoscopy is considered globally the most reliable and easy to access endoscopic technique for detecting and manipulating mucosal colonic lesions. It is provided in highly different settings such as private practice endoscopy suites, hospital-based outpatient departments and tertiary referral centers, and performed by endoscopists with different experience and annual case volume. The complexity of the procedures performed depends on the available facilities and varies from purely diagnostic colonoscopy with or without basic polypectomy to complex endoscopic resections using endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) techniques. Colonoscopy is generally considered safe and well tolerated by the majority of patients, especially when no advanced procedures are conducted. Thus, complications are closely related to the complexity of colonoscopy, endoscopists’ experience and skills and facilities availability [1,2]. The incidence of major colonoscopy complications and 30-day outcome are set as quality indicators [3,4]. It is the endoscopist’s duty to assess the risk of complications in each specific case, to implement strategies to minimize the risk and last but not least once complications occur, to informahealthcare.com
10.1586/17474124.2014.925797
be able to recognize them and treat them accordingly. The endoscopist has to discuss with the patient and his family members the risk for complications, management options and potential consequences and informed consent should be obtained. A lexicon including standard terminology and a classification system of adverse events was proposed recently by the American Society of Gastrointestinal Endoscopy [5]. According to this, events that should be recorded as complications are the ones that result in an unscheduled admission; lengthening of hospital stay; a second unplanned endoscopic procedure; urgent intervention, including blood transfusion; urgent surgery; or lethal outcome. For grading the severity of complications, a scale from mild to major was used, depending on the duration of additional hospital stay and the need for transfusion or surgery. There are no large studies on the management of colonoscopy complications and no consensus algorithms are provided regarding the care of these patients due to the rarity of these events. Most of the data come from retrospective studies reporting on the incidence of complications and not focusing on the management of these cases. This review summarizes current literature and
Ó 2014 Informa UK Ltd
ISSN 1747-4124
963
Review
Paraskeva & Paspatis
expert consensus on the management of major colonoscopy complications. Management of bleeding complications of colonoscopy
Expert Review of Gastroenterology & Hepatology Downloaded from informahealthcare.com by University of Queensland on 03/13/15 For personal use only.
Risk assessment
Diagnostic colonoscopy is not associated with bleeding events unless cold biopsy samples are taken. The vast majority of these events are mild, although clinically significant bleeding cases have been reported, mainly in patients with underlying coagulopathy [1,6]. Bleeding occurs mainly after polypectomy either as an early (intraprocedural or within 24 h) or a late (>24 h) event. A small amount of bleeding, following polypectomy, that is controlled by endoscopic means or spontaneously ceased is common and is not considered as a complication [5]. Postpolypectomy bleeding (PPB) is defined as visible blood loss or melena occurring at any time up to 2 weeks following the procedure requiring transfusion, surgery or further endoscopic therapy [4]. Patient’s need for transfusion or surgery makes a bleeding episode major, otherwise it is characterized as minor. Intraprocedural bleeding is not considered as a complication unless it results in hospitalization, transfusion or operation [5]. Late-onset bleeding poses a more significant problem since it leads to urgent re-hospitalization or unplanned interventions. The lag time between baseline colonoscopy and the occurrence of bleeding may reach up to 2 weeks, and the patient may visit a different hospital without the initially treating endoscopist being notified about the referral. Delayed occurrence is the main reason why many complications remain underreported [7]. Endoscopic series suggest that the overall risk for PPB should be less than 1%, otherwise a review of polypectomy practices for inadequate performance detection should take place [3,8]. The reported incidence for PPB shows a great variation (0.3–6.2%), mainly due to differences in the definition of bleeding, the complexity of polyp cases and study set up [6,9–13]. Factors associated with the incidence of PPB are either related to polyp characteristics such as size, morphology and location of the polyp, or to the patient’s health status such as age >65 years, the presence of hypertension, renal disease and anticoagulant intake [14,15]. The size of the polyp has been reported as a major risk factor for PPB [10,14,16–19]. Polyps larger than 10 mm carry a 4.5-fold greater risk than smaller ones [10]. The risk for PPB is further increased by 9% for every additional millimeter of polyp size [19]. Right-side colon polyps, sessile morphology and polyps with thick stalks are also reported to be at an increased risk for PPB [11,20,21]. In general, the risk of adverse events after colonoscopy is positively correlated with polypectomy complexity. Adjusted risk of cumulative adverse events is gradually increasing with the use of cold forceps (1.21, 95% CI: 1.01–1.44), ablation (3.75, 95% CI: 2.97–4.72), hot forceps (5.63, 95% CI: 4.97– 6.39), snares (7.75, 95% CI: 6.95–8.64) or complex colonoscopy (8.83, 95% CI: 7.70–10.12) [1]. The use of cautery is associated with a 6–9-fold increased risk of PPB compared with cold techniques [1,22]. Nowadays, cold snare polypectomy 964
is considered as the gold standard technique for the removal of diminutive polyps [23]. The use of hot biopsy technique is no longer recommended. The type of the electrosurgical current applied for the polypectomy affects the incidence and the time of PPB occurrence. It has been found that the use of pure cut or blended current increases the risk of immediate PPB, while the use of pure coagulation current is associated with late-onset PPB [14,24]. Although most endoscopists use blended or pure coagulation current, some may choose to use pure cut waveforms for EMR and ESD [25]. The selection of the electrocautery waveform may be adjusted in a case-specific manner as it may be more practical to treat an early PPB event. Endoscopists should evaluate the risk of PPB or thermal injury for each individual case and engage the therapeutic option with the lowest risk, when clinically appropriate. Modern electrosurgical units with microprocessor control are associated with lower rates of PPB compared with the use of pure cut or coagulation current [15]. Clinical assessment
Most episodes of postcolonoscopy bleeding occur within 48 h, with only about 10% of the events occurring later on [9,10,26]. In about 40–60% of the cases, bleeding is self-limited without transfusion requirement [10,26,27]. However, some patients are readmitted with hemodynamic instability and multiple recurrent bloody bowel movements spaced at close intervals. (i.e., 30’–60’), indicating a likelihood of ongoing arterial hemorrhage. Patient management includes adequate volume resuscitation and transfusion of blood products as appropriate (target hemoglobin levels of 8–9 g/dl in most patients). Hypotension usually responds to fluid resuscitation. Ideally, patients should have normal clotting function, with an INR of less than 1.6 and platelet count of more than 50,000 to 70,000. Resuming anticoagulation within a week following polypectomy is an independent risk factor for delayed PPB (OR 5.2) [19]. The decision to reverse anticoagulation or consider platelet or fresh frozen plasma transfusion depends on the severity of the bleeding episode and should be weighed against patient’s risk for a thrombotic event. Urgent colonoscopy
Whether all patients presenting with rectal bleeding within 2–3 weeks following polypectomy need an urgent colonoscopy or clinical signs are available to safely spare unnecessary procedures is still under debate. No relative study has been conducted to answer this question with only experts’ opinion existing. The most common approach is to offer colonoscopy within 24 h to all patients presenting with bloody stools, similarly to gastroscopy being the gold standard in peptic ulcer bleeding [10,19]. Patients with no major stigmata (adherent clots, nonbleeding visible vessels and severe active bleeding) that are otherwise healthy can be quickly discharged. The prognostic value of endoscopic stigmata during urgent colonoscopy has not been adequately studied. Expert Rev. Gastroenterol. Hepatol. 8(8), (2014)
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Management of complications after colonoscopy
Another option is to perform urgent colonoscopy selectively in those with more than three bowel movements in 24 h and/or persistent hemodynamic instability or recurrent bleeding, and observe those who respond to initial resuscitation, always having in mind the risk for a poor outcome or the need of an urgent intervention [28]. Since bleeding is self limited in most cases, close clinical and hemodynamic monitoring might be enough for those who pass one or two semiformed black stools per day. An alternative clinical test for selecting patients suitable for urgent colonoscopy is to check the effluent for blood after providing colonic preparation [29]. Patients may receive colonic purge rapidly (usually a total of 4–6 l of polyethylene glycol solution within 3 h) after resuscitation and only proceed to colonoscopy if the effluent indicates ongoing bleeding. If the bloody effluent clears with preparation, and the patient is clinically stable, with minor comorbidities, withholding colonoscopy may be a reasonable option. Due to the cathartic properties of intraluminal blood, the use of bowel preparation depends on the endoscopist’s discretion and patient’s clinical condition and in cases of severe hematochezia someone may choose to go directly for urgent colonoscopy after patient resuscitation [30]. Since there are no validated therapeutic algorithms, the safest and the most efficacious approach remains to be proved in large-scale prospective, randomized trials. Using a decision model, it was calculated that a tandem colonoscopy for identification and treatment of PPB is beneficial in about 22% of patients, corresponding to a number needed to treat of 4.5 patients [31]. In elective colonoscopies on the following day in an otherwise stable patient, standard colonic preparation is the proper decision. The use of water pump in actively bleeding patients is strongly encouraged despite the absence of literature data. Choosing the proper endoscopic method
There are no strict rules stating which is the preferable endoscopic method for applying hemostasis in cases of PPB. Technique selection is based on endoscopist’s preference and device availability depending also on certain characteristics of the lesion and location of bleeding. The most commonly applied method is through the scope (TTS) clips, alone or in combination with a thermal method and/or adrenaline injection [6,21,32]. In cases of immediate massive PPB, the snare may be used to grasp the upper part of the remaining stalk, temporally stopping the bleeding and revealing the bleeding site more clearly. An endoloop or a clip can be subsequently applied [33]. The use of two endoscopes has been reported as an option to facilitate the procedure [34]. Injection of 1:10,000 diluted epinephrine into the site of bleeding is also used to reinforce instant hemostasis [35]. Bleeding that occurs after resection of a pedunculated polyp can be stopped mechanically by applying a clip or an endoloop [36–39]. A residual stalk must be present for the endoloop to remain in place. Endoscopic band ligation has also been used to treat PPB in cases of pedunculated or informahealthcare.com
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semipedunculated polyps [40–42]. In the cases of sessile polyps, recognition of the bleeding vessel allows hemostasis using clips or a thermal method. Urgent colonoscopy for PPB following EMR for large sessile polyps reveals a cautery ulcer covered with adherent clot or marginal bleeding. Removal of the blood clots by irrigation or with a cold snare guillotining technique allows the exposure of visible vessels that may be treated via endoscopic clipping. Bleeding from the margins is usually stopped with the application of a thermal method such as Argon Plasma Coagulation. The combination of endoclips with endoloop to close off the polypectomy ulcer, similar to the one used for perforation sites closure, has also been reported in successful treatment of late-onset PPB [43,44]. Caution is necessary during the application of hemostatic techniques as transmural injury from thermocoagulation and perforation during clipping have been reported among other complications [21,45]. Recently, an over-the-scope clip (OTSC; Ovesco Endoscopy AG, Tuebingen, Germany) has become available. This clip has a set up that works similarly to variceal band ligation system. Although the OTSC has been primarily used for the closure of perforations, it was also shown to be effective for PPB control refractory to other endoscopic modalities [46]. The advantage of using this device is that it can grasp a much wider area and larger volume of tissue than TTS clips. For ESD procedures, an excellent endoscopic tool to prevent or stop bleeding from the large submucosal vessels exposed during the procedure is the purposed designed coagulation forceps (Coagrasper; Olympus Medical Systems, Tokyo, Japan) [47]. Reported success rate of endoscopic treatment is very high (up to 90%) [48]. What if endoscopy fails to control bleeding?
Decisions on such, indeed, rare refractory cases should be based on local expertise and individual experience. Interventional radiologists can selectively embolize the feeding artery with absorbable gelatin sponge (Gelfoam) or coins [49]. Subtotal colectomy is always kept for patients with continuous bleeding that fails to be controlled by endoscopic means or embolization, when available [50,51]. Studies with PPB cases and their management are included in TABLE 1. Management of perforation after colonoscopy
A colonic perforation is usually defined as evidence of air, luminal contents or instrumentation outside the gastrointestinal tract [4]. A small perforation that is recognized during colonoscopy and sealed endoscopically without interfering with completion of the procedure or lead to a change in the management plan is considered as an event [5]. Grading the severity of a perforation is based on the prolongation of hospital stay and the need for surgery [5]. Intra- and/or postprocedural perforation that needs surgery is graded by definition as serious complication. The use of CO2 insufflation is routinely recommended in gastrointestinal endoscopy [52] and especially in cases with an iatrogenic perforation. If colonoscopy is undertaken under 965
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Table 1. Studies with postpolypectomy bleeding cases and their management. Ref.
Study (year)
Type of study
Bleeding cases (number of patients)
Endoscopic treatment (number of patients)
Angiography and embolization (number of patients)
Surgery to control bleeding (number of patients)
Heldwein et al. (2005)
Prospective
36
33
0
3
[11]
Sorbi et al. (2000)
Retrospective
83
80
1
2
[90]
Parra-Blanco et al. (2000)
Retrospective
63
62
0
0
[32]
Paspatis et al. (2008)
Retrospective
80
79
0
1
[6]
Singh et al. (2009)
Retrospective
21
7
0
2
[26]
Yousfi et al. (2004)
Case control
81
51
1
2
[27]
Burgess et al. (2014)
Prospective
62
21
1
2
[13]
room air and a perforation occurs, switch to CO2 insufflator should ideally be performed, if available (FIGURE 1). Risk assessment: causes of perforation
Intraprocedural perforation during diagnostic colonoscopy is extremely rare and occurs as a result of mechanical factors. It may occur by sideway pressure of a formed loop, and even more uncommonly because of a direct scope trauma or when taking biopsies from a distended cecal wall in an elderly patient. Preventive measures for this type of perforations include engaging the shortening technique of colonoscopy and avoiding high-risk maneuvers such as ‘pushing through’ or ‘sliding by’ or taking biopsies from a distended cecum. Patients with signs of colonic inflammation are also more likely to have a perforation. Preexisting conditions associated with an increased risk include acute colitis, a tumor or diverticula-based stricture, a fixed loop due to adhesions, prior radiation therapy and therapeutic procedures such as endoscopic resection and stenosis dilatation. The most common site of perforation is the sigmoid colon and the rectosigmoid junction (70%) [6,53]. Most commonly, perforations are induced by therapeutic interventions such as polypectomy with electrocautery application. This is either due to thermal injury beyond the submucosa or due to full thickness cut with the snare during standard polypectomy and EMR, or with the knife during ESD. Highdensity or prolonged current application can cause full thickness burn of the bowel wall. The right side of the colon is by far the most frequently reported site of perforation after polypectomy due to its thinner wall and the relative complexity in removing proximal lesions. The reported incidence of perforation in published series including diagnostic colonoscopies ranges from 0.016 to 0.2% and up to 1.1% for conventional polypectomy [6,11,54–57]. For more advanced therapeutic techniques, such as colonic ESD, incidence of perforation can be up to 5%, depending on the lesion morphology and location and the endoscopist’s skills [58]. However, recent data have shown perforation rates in colorectal ESD as low as 1.6% [59]. Corresponding rate of perforation during colonic EMR is 1.3% [60]. 966
It has been suggested that perforation rates greater than 1 in 500 for all colonoscopies or 1 in 1000 for screening colonoscopies should prompt evaluation of endoscopic practices [3]. Preventive measures include submucosal injection, although its efficiency in limiting the depth of thermal injury has only been proven in animal models. Today it is performed by about 80% of practicing clinical gastroenterologists for the piecemeal removal of large sessile lesions, particularly those located in the right colon and for ESD technique [61]. Clinical presentation
Perforations recognized during the procedure range from 25 to 60%, depending on the type of the therapeutic intervention performed and the endoscopist’s awareness [11,62]. Direct endoscopic recognition of a perforation forms a favorable scenario in which diagnosis is achieved before the patient develops any symptoms, and the options for either endoscopic on site repair or urgent surgery is on the table (FIGURE 1). Clinical suspicion of a perforation that is not endoscopically apparent should be raised on the presence of unremitting pain during or immediately after the colonoscopy and abdominal distension accompanied with patients’ inability to expel the air. Clinical deterioration within hours after colonoscopy requires radiological assessment and surgical review (FIGURE 2). This is often the case of a perforation during diagnostic colonoscopy because of the large size of the bowel defect created in these cases [63]. The majority of perforations present within 24 h [64]. Only a few cases may develop symptoms after that period mainly due to the formation of a coagulation eschar that is necrotized and drops in up to 2–3 days [64]. There are few reports of small perforations covered with omentum that remain silent and diagnosed with a delay of up to 14 days [65]. Clinical status and symptoms in postpolypectomy perforations are related to the severity of induced tissue injury. This ranges from a transient transmural burn without frank perforation (postpolypectomy coagulation syndrome), to perforations sealed by omentum and expand to free perforation with extensive leakage of bowel content and induction of diffuse peritonitis. Expert Rev. Gastroenterol. Hepatol. 8(8), (2014)
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Management of complications after colonoscopy
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Postpolypectomy syndrome (PPS) Intra-procedural expresses symptoms that reflect irritation recognition of the overlying serosa. PPS presents with localized pain, low fever and mild leukocytosis and its discriminating features Switch to CO2 over true perforation is the lack of severe (if available) symptoms and of free intraperitoneal or subdiaphragmatic air. The diagnosis of PPS may be misleading, therefore Endoscopic closure Endoscopic closure patients need very close follow-up due to feasible impossible the natural course of the syndrome, which either subsides with conservative treatment or leads to a frank perforation. Clinical deterioration Patient Surgery The incidence of PPS seems to be higher (sepsis signs, peritonitis) clinically stable at present due to the increasing application of advanced endoscopic polypectomy techniques. Especially after colon ESD of Conservative large polyps in sites other than the rectomanagement sigmoid, the risk of PPS may be up to 40.2% [66]. Figure 1. Algorithm for the management of intraprocedural recognized colonic A small perforation is usually covered perforations. with intestinal creeping fat and omentum. The patient suffers from localized pain and tenderness, accompanied by free air detected in and efficient and furthermore allows continuing the procedure abdominal x-rays and CT scan, but without signs of sepsis. In such as ESD. Studies on endoscopic closure of iatrogenic perfothese cases, 24 h of close clinical follow-up is mandatory. rations were initially conducted in porcine models followed by Rapid patient improvement favors conservative treatment while retrospective reports of clinical outcomes. Clips were shown to clinical deterioration prompts surgical intervention. In clinical produce a successful approximation of mucosa and submucosa practice, this decision may be a real dilemma in selected layers, while apposition of muscularis propria and serosa are not possible because of the superficial clipping. This partial situations. The time of recognition of the perforation followed by effec- thickness approximation has been shown to be effective and tive management is very important for the outcome. Data sufficient for the healing of perforation in animal models [74]. show that when the perforation was recognized within 24 h the mortality was very low, while a delay in recognition of more than 24 h after colonoscopy increased mortality up to Late diagnosis (>4 h post procedure) 66% [67]. Endoscopic management of perforations
Several case series report on the feasibility of conservative treatment of colonic perforation (TABLE 2) [11,68–71]. No prospective studies exist and no sufficient data to make clear recommendations on the indications of the endoscopic treatment of perforation. Endoscopic repair of perforation prerequisites that the damage is recognized during the endoscopy, the colon is clean to prevent leakage of bowel content outside the bowel and complete closure of the gap is achieved in order to reduce the risk of peritonitis. Occasionally, a perforation is diagnosed postprocedurally and if preparation is still adequate (within 4 h after the procedure) endoscopic therapy may also be considered [72,73]. The TTS clips Quickclip2 and EZ (Olympus Medical Systems, Tokyo, Japan); Resolution Clip (Boston Scientific, Natick, MA, USA); Instinct Endoscopic Hemoclip (Cook Medical, Winston–Salem, NC, USA) are currently the standard tools for sealing acute perforations. Their use is simple, fast informahealthcare.com
Stable clinical condition, + CT: no fluid collections
Unstable clinical condition, ± CT: fluid collections
Conservative management
Deterioration of clinical condition (sepsis signs, peritonitis)
Surgery
Figure 2. Algorithm for the management of late recognized colonic perforations.
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Table 2. Series of endoscopic closure of iatrogenic colonic perforations. Ref.
Study (year)
Type of study
Perforations (number of patients)
Initial endoscopic closure (number of patients)
Method
Successful endoscopic closure (number of patients)
Transferred to surgery out of clipped cases (number of patients)
Cho et al. (2012)
Retrospective multicenter
32
29
TTS clip
22
7
[76]
Magdeburg et al. (2013)
Retrospective
105
71
TTS clip
60
11
[91]
Voermans et al. (2012)
Prospective multicenter
13
13
OTSC
12
1
[83]
Kim et al. (2013)
Retrospective
27
16
TTS clip
13
3
[92]
Gubler (2012)
Case series
9
9
OTSC
6
3
[93]
OTSC: Over-the-scope clip; TTS: Through the scope.
Endoscopic clip closure however demonstrates certain limitations. It may be very difficult to succeed and verify the complete sealing of the perforation. The open prongs of the clip should reach and bridge the edges of the defect and this is not always feasible, especially in defects larger than 2 cm or round in shape or having reverted edges. Efforts to apply the clips may take time during which air and liquid luminal contents may leak into the peritoneal cavity. Technical advice and maneuvers to enhance successful clip closure have been recently published [75]. If clip closure is incomplete or the clips detach early, minor leakage can develop producing ambiguous symptoms and surgery may be delayed beyond optimal period. Perforation cases that undergo surgery after failure of endoscopic closure may have peritoneal abscess formation and fistula and might need aggressive surgical treatment including colon resection with diversion [76]. In expert centers performing ESD, while the perforation rate is higher and therefore endoscopists are alert for a possible deeper layer dissection, endoscopic closure is more frequently attempted and successfully applied. This type of perforations is usually less than 10 mm in size and its immediate recognition is eased by the use of indigo carmine dye of the muscularis propria and the high definition vision [77]. In the cases where the noncolored muscularis propria is visible in the base of the polypectomy ulcer like a target, early endoscopic treatment is warranted since this is a sign of deeper burn and potential perforation. Recognition of the so-called ‘target sign’ allows prompt endoscopic diagnosis and treatment sparing the need for prolonged medical management or surgical intervention [78]. Successful endoscopic closure of colon perforation after failure of TTS clip placement has been achieved with band ligation [79,80]. In these cases, a gastroscope is used to fit with the band ligator, and the perforation site is suctioned into the band ligator cup, resulting in the closure of the perforation. For larger defects, TTS clips may be used in combination with a detachable snare (Endoloop-Olympus Medical Systems, Tokyo), whereas the clips are placed around the circumference of the perforation and lassoed together with the Endoloop [81]. 968
Another technique described for large defects closure is the omental patch technique first applied on large perforations after gastric EMR and ESD [79]. It is based on the principle of pulling the omentum when visible, through the defect and clip it with the edges of the perforation. Recently, the OTSC has shown impressive results on the endoscopic closure of colonic perforations and fistulae [46,82]. The OTSC performs full thickness closure of gaps up to 20 mm in size. It also provides the possibility of tissue approximation with the use of a grasping device and retraction of the defect into the OTSC cap. Small perforations (
