INTRODUCTION

Lower gastrointestinal (GI) endoscopy can be broadly classified into diagnostic and therapeutic. Diagnostic lower GI endoscopy includes colonoscopy, flexible sigmoidoscopy, pouchoscopy, ileoscopy or colonoscopy via stoma, and endoscopy of diverted bowel. Diagnostic lower GI endoscopy usually requires tissue biopsy, and occasionally a tattoo. Therapeutic lower GI endoscopy includes endoscopic hemostasis, polypectomy, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), endoscopic full-thickness resection (EFTR), endoscopic balloon dilation (EBD), endoscopic stricturotomy (ESt), endoscopic strictureplasty (ESTx), endoscopic sinusotomy (ESi), endoscopic fistulotomy, endoscopic banding, endoscopic ligation, endoscopic stenting, percutaneous endoscopic colostomy, endoscopic detorsion and decompression, endoscopic suturing, and endoscopic removals of foreign bodies or bezoars.

Commonly performed colorectal surgeries for inflammatory bowel disease (IBD), colorectal cancer (CRC), and other colorectal diseases are examination under anesthesia (EUA), total, subtotal, segmental colectomy, total proctocolectomy, and proctectomy with various forms of anastomosis, low anterior resection (LAR), abdominopelvic resection (APR), restorative proctocolectomy (RPC) with ileal pouch–anal anastomosis (IPAA), continent ileostomy, ileostomy, colostomy, coloplasty, fistula repair, mucosal or muscle flaps, hemorrhoidectomy, and topical stem cell injection therapy. The surgery is performed in an open, laparoscopic, robotic, or hybrid fashion.

All those lower GI endoscopies and colorectal surgeries are associated with procedure-associated complications.

COMMON ENDOSCOPY AND SURGERY-ASSOCIATED COMPLICATIONS

Complications can occur after diagnostic or therapeutic lower GI endoscopy, with the latter carrying a high risk. The main endoscopy-associated adverse events are abdominal pain and discomfort, cardiopulmonary complications, perforation, bleeding, infection, and even mortality. Other complications include post-polypectomy electrocauterization syndrome and gas explosion. The American Society for Gastrointestinal Endoscopy (ASGE) and the European Society of Gastrointestinal Endoscopy (ESGE) have published a series of guidelines on adverse events of GI endoscopy. The ASGE and UESG classifications are based on the type of endoscopy (upper or lower GI), and the frequency, location, and nature of complications. For colonoscopy, the ASGE guidelines listed the following categories: cardiopulmonary complications, perforation, hemorrhage, postpolypectomy electrocoagulation syndrome, infection, gas explosion, abdominal pain or discomfort, mortality, and miscellaneous complications. Complications from special endoscopic procedures, such as colonic dilation stent placement and foreign body removal, are described. ^,

Most of these endoscopy-associated complications can be managed conservatively (e.g., nasogastric tube placement, intravenous fluids, and antibiotics) or with corrective endoscopy. Some of these complications may require surgical intervention, such as corrective surgery.

Postoperative complications are common following colorectal surgery. Early complications include surgical site infections (SSIs), thromboembolic events, anastomotic leaks (ALs), abdominopelvic abscess or sepsis, postoperative bleeding from vascular injury or the use of anticoagulants or antiplatelets, anastomotic bleeding, postoperative ileus (POI), urinary rection and urinary tract infection, bowel obstruction, the adverse consequence of iatrogenic injury to adjacent organs, and cardiopulmonary complications. SSIs are the most common cause of morbidity for patients undergoing colorectal surgery. The Centers for Disease Control and Prevention defines an SSI as an infection that occurs after surgery in the part of the body where the surgery took place. SSIs can be superficial infections involving the skin only. Other SSIs are more serious and can involve tissues under the skin, organs, or implanted materials. Incisional SSIs can be superficial or deep, primary, or secondary (e.g., from hematoma). ALs can lead to abscess or sepsis, requiring radiographic, endoscopic, or surgical drainage. With routine prophylaxis, deep vein thrombosis (including portomesenteric vein thrombosis) and pulmonary embolism are not common but can occur in patients at risk, such as those with IBD and CRC. POI is also common after colorectal surgery. On rare occasions, increased intraabdominal pressure can cause abdominal compartment syndrome, leading to organ failure.

Late complications after colorectal surgery include anastomotic bleeding, anastomotic strictures, anorectal strictures (e.g., anorectal surgery, such as distal rectal, ESD, and hemorrhoidectomy), anastomotic sinus or fistula from chronic AL (e.g., vaginal fistulas, bladder fistulas, enterocutaneous fistulas, and perianal fistulas), bowel dysfunction, fecal incontinence, genitourinary complications, sexual dysfunction (e.g., erectile dysfunction, retrograde ejaculation, and dyspareunia), and infertility. LAR is increasingly performed in patients with rectal cancer. LAR syndrome consists of a collection of symptoms of fecal incontinence or leakage, bowel frequency or urgency, loose stools, incomplete evacuation, and tenesmus. Abdominal cutaneous nerve entrapment syndrome (ACNES) can occur after colorectal surgery, causing chronic postoperative abdominal pain. Stoma-related complications can develop in patients with ileostomy or colostomy, dehydration, electrolyte derangements, or renal insufficiency from high volume output, retraction, necrosis, prolapse, and parastomal hernia. These late complications usually persist unless corrective endoscopic or surgical procedures are performed.

CLASSIFICATION OF ADVERSE EVENTS OF ENDOSCOPY AND SURGERY

Lower GI endoscopy is performed in an office, endoscopy suite, intensive care unit (ICU), or intraoperative setting. Simple surgical procedures can be performed in the office or operating room. In the United States, almost all patients undergoing endoscopy or surgery require sedation or anesthesia. The American Society of Anesthesiologists (ASA) classification is routinely used to quantify the risk before endoscopic or surgical procedures. The ASA classification is initially designed to grade physical status and assess patients’ anesthetic risk. ASA class I is a normal healthy patient; ASA class II is a patient with mild systemic disease; ASA class III is a patient with severe systemic disease; ASA class IV is a patient with severe systemic disease that is a constant threat to life; ASA class V is a moribund patient who is not expected to survive without the operation; ASA class VI, a declared brain-dead patient whose organs are being removed for donor purposes. The ASA class is found to be associated with the risk of postoperative complications. Using the Clinical Outcomes Research Initiative National Endoscopic Database, investigators identified 192 perforation events during 1,144,900 colonoscopies and found that a higher ASA class along with age, female sex, hospital setting, delivery of therapy, and polyps >10 mm are risk factors. In a study of 23 patients with colonoscopic perforation, a high ASA class was found to be associated with a longer hospital stay and a poor prognosis after colonic perforation than those with a lower ASA class. Therefore, documentation of the ASA class before endoscopy or surgery is critical for the prevention and management of complications.

The 100-point Charlson Comorbidity Index (CCI) has also been used in the preparation and execution of colorectal surgery. CCI consists of prior myocardial infarction, congestive heart failure, peripheral vascular disease, cerebral vascular disease, dementia, chronic pulmonary disease, rheumatological disease, peptic ulcer disease, mild liver disease, diabetes (1 point each); cerebrovascular events, moderate-to-severe renal disease, diabetes with chronic complications, cancer without metastases, leukemia, lymphoma (2 points each); moderate-to-severe liver disease (3 points each); metastatic solid tumor, and acquired immunodeficiency syndrome (6 points each). ^, CCI are comorbidity-based measures that are developed to predict mortality within 1 year of hospital admission in patients without trauma.

The Clavien-Dindo Complication Classification (CDCC) system has been used for scoring surgical complications, including complications from colorectal surgery. CDCC is widely used for assessing and reporting postoperative morbidity. Grade I is any deviation of the normal postsurgical course without a need for pharmacological therapy or intervention; grade II is surgical complications requiring pharmacological therapy; grade IIIa is surgical complications requiring surgical, endoscopic, or radiologic intervention not under general anesthesia; grade IIIb is complications requiring surgical, endoscopic, or radiological intervention under general anesthesia; grade IVa is life-threatening complication requiring management in the intensive care unit with single organ failure; grade IVb is life-threatening complication requiring ICU management with multiorgan failure; and grade V is patient’s death. For example, presacral sinus treated by endoscopic sinusotomy with patients under conscious sedation or monitored anesthesia care is grade IIIa. CCDC grade I–II is considered minor complications while CCDC grade III–V is categorized as severe complications.

The correlation between CCI and CDCC has been investigated in colorectal surgery. A study of 958 consecutive patients hospitalized for colonic cancer showed a correlation between CCI and CDCC (r = 99.4%; 95% confidence interval [CI]: 99.3–99.5%). However, the CCI showed a greater ability than the CDCC to predict hospital stay, particularly in patients with multiple postoperative complications. CCI better predicts readmission than CDCC in the subgroup of patients with more than one complication.

Modified from the Clavien-Dindo classification, the adverse events in gastrointestinal (GI) endoscopy (AGREE) classification was proposed. The AGREE classification consists of no adverse event; grade I is an adverse events with any deviation of the standard postprocedural course, without the need for pharmacological treatment or endoscopic, radiological, or surgical interventions, presentation at the emergency room, without any intervention, or hospital admission <24 hours, without any intervention, or allowed therapeutic regimens such as drugs as antiemetics, antipyretics, analgesics, and electrolytes, or allowed diagnostic tests, such as radiology and laboratory tests; grade II is an adverse events requiring pharmacological treatment with drugs other than those allowed for grade I adverse events or blood or blood product transfusions or hospital admission >24 hours; grade III is an adverse events requiring endoscopic, radiologic, or surgical intervention; grade IIIa is an endoscopic or radiological intervention; grade IIIb is a surgical intervention; grade IV is an adverse events requiring intensive care unit/critical care unit admission; grade IVa is single organ dysfunction; grade IVb is multiorgan dysfunction; and grade V is death of patient.

Other instruments have been proposed and compared postoperative morbidities, such as the Association of Surgery of the Netherlands and the Trauma Registry of the American College of Surgeons. The two different classification systems are not necessarily correlated in colorectal surgery.

FECAL INCONTINENCE

Structural or functional bowel dysfunction can result in major morbidities in patients undergoing colorectal surgery, especially surgery in the rectum and pouch. The clinical presentations range from diarrhea, constipation, and dyschezia to incontinence. Various instruments have been developed to measure the degree of fecal incontinence in general, including the Memorial Sloan Kettering Cancer Center Bowel Function instrument, the Working Party on Anal Sphincter Replacement instrument, the International Consultation on Incontinence Modular Questionnaire-Bowels (ICIQ-B), the Modified Manchester Health Questionnaire (MMHQ), the Gastrointestinal Quality of Life (GIQoL), the Direct Questioning of Objectives (DQO) scale, the Childhood Incontinence Quality of Life scale, the Fecal Incontinence Quality of Life (FIQL), the Fecal Incontinence Severity Index (FISI), and the Cleveland Clinic Incontinence Score (CCFIS; or the Wexner Incontinence Score). Some of the fecal incontinence instruments (such as FIQL, FISI, and CCFIS) have been used to measure the severity of incontinence in patients after colorectal surgery, including LAR, rectal pexy, RPC and IPAA, and transanal endoscopic microsurgery. FIQL assesses lifestyle, coping/behavior, depression, self-perception, and embarrassment.

Endoscopic submucosal dissection (ESD) has been used for the treatment of rectal dysplasia. Fortunately, fecal continence or rectal strictures are rare. One of the authors (B.S.) has routinely used endoscopic stricturotomy with a circumferential fashion to treat anorectal ring stricture, pouch-anal anastomotic strictures at the distal diverted rectum, or pouch. To date, no patients reported fecal continence.

Corrective colorectal surgery, such as J-pouch reconstruction, conversion of a J-pouch to a Kock pouch, pouch excision, completion proctectomy, and revision of distal bowel anastomosis, is believed to carry a high risk for the development of fecal incontinence. Unfortunately, there is scant literature on the topic.

SEXUAL DYSFUNCTION

Various existing instruments are used to characterize male and female sexual dysfunction. Colorectal surgery, pelvic surgery, and pouch surgery can cause male and female sexual dysfunction. The International Index of Erectile Function-5 (IIEF-5) is commonly used to assess male sexual dysfunction. The IIEF-5 consists of five questions reflecting global erectile function and the score ranges from 0 to 25. The severity of male patients’ erectile dysfunction is set at the standard of severe (<7), moderate (8–11), mild to moderate (12–16), mild (17–21), and no dysfunction (22–25). ^, The Female Sexual Function Index (FSFI) is commonly performed to assess female sexual dysfunction. The FSFI is a self-reported questionnaire containing six domains in desire, arousal, lubrication, orgasm, satisfaction, and pain. FSFI has been widely used in the assessment of female sexual dysfunction following colorectal surgery procedures, including IPAA. ^, A simplified form of Sexual Function Questionnaires has also been used to measure sexual dysfunction, for example in female patients with IPAA.

Corrective colorectal surgery involving the pelvic area may carry a higher risk for male or fecal sexual dysfunction than index colorectal surgery, although the literature is limited. In this author’s experience, corrective, therapeutic lower GI endoscopy rarely results in sexual dysfunction.

SUMMARY AND RECOMMENDATIONS

The ASA classification or the CCI should be routinely used for preprocedural risk stratification for endoscopy and surgery that require sedation, monitored anesthesia care, or general anesthesia. The CDCC system and AGREE are used for scoring surgical and endoscopic complications, respectively. Existing instruments for fecal continence and sexual dysfunction can also be used for the measurement of procedure-associated complications. We should develop procedure-specific (e.g., EBD) or complication-specific (e.g., EBD perforation) instruments to stratify the severity of the adverse events and guide rescue strategies. More data are needed to stratify the severity of systemic and functional complications after corrective lower GI endoscopy or colorectal surgery.