Damage Control: Management of Procedure-Associated Complications

Causes, Risk Factors, and Mechanisms

The main mechanisms or etiology for perforation are air insufflation, mechanical trauma, polypectomy, and thermal injury. The diagnostic colonoscopy-associated perforation largely results from mechanical force, due to looping and angulation of the scope shaft or simply the barotrauma from the tip of the scope. In contrast, therapeutic endoscopy–associated perforation is mainly the consequence of electrocoagulation, such as hot snare polypectomy, EMR, ESD, and ES, fistulotomy or sinusotomy, with EBD as an exception. The difference in the mechanisms may explain why the size of diagnostic colonoscopy–associated perforation is generally larger than that from therapeutic colonoscopy.

Risk factors associated with complications of EBD-associated perforation in patients with IBD included concurrent active mucosal inflammation, corticosteroid use, ileosigmoid or ileorectal anastomotic strictures, and disease-related primary strictures. A multivariate analyses of a Japanese national inpatient database of 345,546 patients undergoing therapeutic colonoscopy showed that the risk factors for bowel perforation were male, renal disease, ESD, tumor size ≥ 2 cm, and the use of drugs like warfarin, nonsteroidal antiinflammatory drugs (NSAID), and corticosteroids. The risk factors for other therapeutic modalities in interventional IBD have not been reported. We speculate that a high degree of underlying inflammation, anatomy of lesions, and endoscopist's expertise play a major role.

Diagnosis of Endoscopic Perforation

In most cases, iatrogenic perforation occurs during the endoscopic procedure, which can and should be recognized or diagnosed onsite, in endoscopy room or endoscopy recovery suite. The general rule is to diagnose earlier and intervene earlier, to prevent complication's complications, such as bowel resection and fecal diversion surgery. The symptoms and signs may occur and the diagnosis of perforation may be made: (1) immediately when the scope is still in situ; (2) at the time in endoscopy recovery room; (3) within 24 h after discharge; or (4) 24 h after the procedure.

The best time for the intervention is rescuing treatment immediately after diagnosis with the scope in situ. However, onsite diagnosis of perforation can be difficulty. Endoscopist may be able to directly see the unintended area of the therapy, such as muscalaris proparia, serosa, or abdominal or pelvic cavity ( Fig. 29.1 ). A second look at the treated area is recommended to identify perforation as well as to assess results of initially planned endoscopic treatment. However, it is not absolutely necessary to traverse all treated strictures with endoscopy. The deep tear from EBD ( Fig. 29.2 ) or electroincision ( Fig. 29.3 ), even in the absence of obvious perforation, should be treated, with endoscopic clips, as a precaution. Sometimes the diagnosis of onsite perforation may be suspected if the patient suddenly experiences abdominal pain, bloating, sweating, difficulty in breathing, tachycardia, drop of blood pressure, and requirement of excessive oxygenation or medications. Malfunction of balloon may cause incidental deep tear and the patient should be monitored closely ( Fig. 29.4 ). EBD for the treatment of stricture at stapled anastomosis can carry a higher risk for perforation than that for the stricture of handsewn anastomosis, based on this author's experience. Extreme precaution should be exerted ( Fig. 29.5 ).

The next critical time for the diagnosis of perforation follows the “30 min role” in the endoscopy recovery room. The index of suspicion should be raised if a patient has excessive pain and bloating, dyspnea, and chills. Stat abdominal imaging is indicated. The alarm for complication is not off even after the patient is discharged from the endoscopy suite. The patient should be closely monitored by him/her-self and family members for at least 24 h. Clear liquid diet is recommended, in case rescuing endoscopy is needed. Late-onset perforation can occur 1–4 days after the procedure, especially when the electrocauterization or electroincision is used. Therefore, patients should be advised to avoid NSAID or anticoagulants and strenuous physical activities for at least 5 days after the endoscopic procedure.

A plain abdominal X-ray is a quick way to diagnose perforation with demonstration of free air under the diaphragm. However, noncontrasted computed tomography (CT) scan is most sensitive modality for the detection of perforation, including demonstration retroperitoneal air which may be missed on plain abdominal radiograph ( Fig. 29.6 ). Another advantage of CT is to detect perforation to the mesentery sheath. For patients with chest pain and back pain who undergo distal large bowel procedure (such as distal rectal or distal ileal pouch stricture, fistula, sinus therapy), retroperitoneal air and pneumomediastinum from perforation is suspected CT chest along with CT abdomen/pelvis is a valuable tool for the diagnosis, although plain chest and abdominal X-ray may be helpful.

Classification of Endoscopic Perforation

Due to complex anatomy and various forms of diagnostic and therapeutic endoscopy in IBD, there is a wide spectrum of iatrogenic perforations in those patients. Iatrogenic, endoscopy-associated perforation can be classified, based on different criteria ( Table 29.2 ). There are correlations between the criteria. For example, the perforation from blunt trauma from the tip of endoscope or electroincision is often located at the endoscopy-treated site; perforation from the trauma from the shaft of looped endoscope is commonly seen at the segment of bowel distal to the endoscopy-treated area; and the perforation from the tip of forward-slippery balloon is usually seen at the bowel segment proximal to the endoscopy-treated area. There can be blunt trauma, unintended resection, dissection, excision, and thermal injury.

Colonoscopic perforation has been classified into postpolypectomy syndrome, perforation without leak, perforation with air leak, perforation with fluid leak, and perforation with feces leak, based on the substance of leak; perforation, pneumoperitoneum, and peritonitis, based on the presence and degree of infection. Endoscopic clips and abdominal decompression may be used in patients with postpolypectomy syndrome, perforation with no leak, or perforation with air leak. Patients with air leak, fluid leak, or feces leak is preferably managed surgically.

The onset of perforation of endoscopy-associated perforation in general can occur: (1) <24 h; (2) 24–48 h and (3) >48 h after the procedure. In contrast, therapeutic (e.g., EBD) IBD-associated bowel perforation often occurs and identified within 24 h after the procedure and late-onset onset of perforation is not common. Air or barotrauma-associated perforation normally present earlier than heat-related perforation. This author would like to propose the classification of onset of perforation in IBD endoscopy into: (1) onset; (2) <24 h; and (3) >24 h ( Table 29.2 ).

The common location of endoscopy-associated perforation is different in IBD versus non-IBD patients. The sigmoid colon is the most common location of colonoscopic perforation in general. In contrast, the common locations of IBD-associated colonoscopic perforation vary greatly, largely depending on the location of endoscopic treatment, diseased segment, and surgery-altered segment ( Table 29.2 ).

The degree of peritoneal contamination is determined by multiple factors: (1) quality of bowel preparation; (2) size of perforation; (3) interval between perforation to salvage endoscopic or surgical procedure; (4) size and depth of perforation; and (5) status of underlying disease ( Table 29.2 ).

The depth of perforation in IBD can be up to subserosa, full-thickness perforation, free full-thickness perforation without spillage of fecal materials, full-thickness perforation with contained abscess, perforation with peritonitis ( Table 29.2 ).

Consequences of Endoscopic Perforation

There are scant publications on the adverse consequence of endoscopic perforation in IBD patients. We previously studied 84 IBD and non-IBD patients who had endoscopy-associated perforation and reported that 4 (6.9%) died, directly resulting from the procedure-related perforation; 55 (65.5%) had other PAC: 3 (3.5%) underwent total colectomy with diverting ileostomy, 28 (33.3%) had bowel resection, fecal diversion, and secondary anastomosis; and 24 (28.6%) had bowel resection with primary anastomosis. We demonstrated that patients who were taking systemic corticosteroids at the time of lower GI endoscopy had a 13-fold higher likelihood of having PAC (95% confidence interval: 1.3, 1839.7; P = .007). Therefore, endoscopy-associated perforation can bear serious consequences.

The adverse consequence of iatrogenic perforation from EBD can be different between the ones from mesentery side and antemesenteric site ( Fig. 29.7 ). The latter results in free perforation with possible peritonitis, while the former can lead to formation of abscess of the mesentery. Both conditions often require bowel resection. However, the extent and technical difficulty of bowel resection for the treatment of iatrogenic mesentery abscess is greater. Therefore, endoscopist would rather pick the “devil” (antemesentery perforation) than the “evil” (mesentery perforation), if he or she would have a choice. This may be an advantage of endoscopic stricturotomy over EBD, as the endoscopist can have a control of depth and location of electroincision. The endoscopist may be able to tell which side of stricture is the antemesentery site, i.e., opposite wall of linear ulcers, and choose the location to cut.