I. INTRODUCTION

A. Demographics of Gastrointestinal, Abdominal, and Anorectal Patients

There are a wide variety of operative procedures for treating gastrointestinal (GI), abdominal, and anorectal diseases. The circumstances of the operation can range from the emergent exploratory laparotomy for bowel obstruction to electively scheduled laparoscopic sigmoid colectomy for diverticulitis. The rate of complications can vary from 2% to 90% depending on the baseline health of the patient and on whether the surgery is elective or emergent. The surgical procedure may be more complex, such as a laparoscopic total proctocolectomy for ulcerative colitis, or less complex, such as a day surgery for hemorrhoidectomy. The patient can be young or elderly, and their baseline health can vary greatly.

B. Consideration of Patient Risk Factors

Patients undergoing emergent operations are not medically optimized and are at increased risk of perioperative complications. Patients undergoing an emergent operation for bowel obstruction, for example, tend to be dehydrated and require increased resuscitation.

The nutritional status of patients undergoing GI, abdominal, and anorectal surgery can also vary widely. Patients with poor preoperative nutritional status are at greater risk for anastomotic leak. Baseline nutritional status can be determined by looking at both longer term indicators of nutritional status, such as albumin (half-life 20 days), and shorter term indicators of nutritional status, such as pre-albumin (half-life 2 to 3 days).

Patients with cardiac risk factors undergoing elective GI, abdominal, and anorectal surgery should be medically optimized according to the American College of Cardiology/American Heart Association (ACC/AHA) Guidelines on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery. β-Blockers should be continued in patients receiving β-blockers prior to surgery, or should be started in patients with intermediate- and high-risk factors according to the ACC/AHA guidelines, if they are not already taking them preoperatively. Patients undergoing emergent GI, abdominal, and anorectal operations are at increased perioperative cardiovascular risk.

There are multiple risk score calculators that can help determine the risk of postoperative pulmonary complications for patients undergoing GI, abdominal, and anorectal surgery. Patients at higher risk of pulmonary complications include, but are not limited to, those with chronic obstructive pulmonary disease (COPD), asthma, smokers, obstructive sleep apnea (OSA), obesity, heart failure, pulmonary hypertension, poor general baseline health, and the elderly.

C. Disposition from the Operating Room

Following surgery, patients undergoing GI, abdominal, and anorectal procedures are commonly admitted to the postanesthesia care unit
(PACU). Patients undergoing more minor procedures such as hemorrhoidectomy, sphincterotomy, pilonidal cyst excision, or perirectal abscess drainage are generally discharged home from the PACU following a short period of observation. It is important to ensure that these patients are discharged with adequate pain medication because these procedures can be very painful.

Patients with multiple comorbidities who undergo emergent surgery often need the increased level of care provided by the intensive care unit (ICU). These unstable patients will proceed directly from the operating room to the ICU, and will not go to the recovery room postoperatively.

II. MANAGEMENT OF COMMON POSTOPERATIVE PROBLEMS

A. Hemorrhage

1. Workup

Postoperative bleeding after GI, abdominal, and anorectal surgery may present either early in the PACU or later on the floor. There are multiple possible etiologies for bleeding in the GI, abdominal, and anorectal patient. These include, but are not limited to, anastomotic bleeding, large vessel injury, splenic laceration, and presacral bleeding.

The signs of postoperative bleeding include tachycardia, hypotension, and low urine output. If there is concern for bleeding, an abdominal exam should be performed, vital signs and urine output should be assessed, and a complete blood count should be obtained.

Hypovolemia causing hypotension and tachycardia may result from underresuscitation, but this is a diagnosis of exclusion, and bleeding should be excluded. The amount of resuscitation the patient received in the operating room should be assessed, in order to determine whether it was appropriate for the duration of the patient’s operation, recorded estimated blood loss, and predicted insensible losses.

A patient who has had a large amount of bleeding in a short period of time may have a “stable” hemoglobin because the hemoglobin has not had time to equilibrate.

2. Management

Once it has been confirmed that there is bleeding, the source of the bleeding needs to be identified. Knowledge of intraoperative events can help to determine the source of the bleeding. For example, mobilization of the splenic flexure during an extended left colectomy or low anterior resection (LAR) would make splenic laceration more likely. Presacral bleeding that was temporized with sterile tacks intraoperatively would make a recurrence of this bleeding more likely.

Hemodynamically unstable patients with persistent transfusion requirements should return to the operating room for definitive management. Anastomotic bleeding may present as GI bleeding or intra-abdominal bleeding depending on the location of the bleeding relative to the GI lumen. If the bleeding is intraluminal, colonoscopy can be performed to control the bleeding.

If the patient remains hemodynamically stable, but there is evidence of ongoing bleeding, the source of bleeding can be further investigated with radiologic imaging. Endovascular angiography can serve as an effective alternative to surgical intervention for GI bleeding in some cases.

B. Pain

Pain is a common postoperative complication after GI, abdominal, and anorectal surgery.

The nature of the surgical procedure will determine the location and characteristics of the pain. Patients who undergo laparotomy primarily experience incisional pain, whereas patients who undergo laparoscopy
commonly experience shoulder pain that is referred from irritation of the diaphragm. Perianal procedures can result in significant pain and discomfort. The most common reason a post-hemorrhoidectomy patient presents to the emergency room is insufficient pain control.

1. Management

Several meta-analyses have investigated the benefits of epidural anesthesia for pain control in both laparoscopic and open colorectal surgery. The results of these studies have been mixed. Some studies report improved outcomes with decreased lengths of stay and complications, whereas others have shown the exact opposite with increased lengths of stay and a higher incidence of urinary tract infections.

An alternative to epidural analgesia is patient-controlled analgesia (PCA). In addition, adjuncts such as intravenous (IV) acetaminophen and, when the risk of bleeding has decreased, IV nonsteroidal anti-inflammatory drugs (NSAIDs), can result in significant improvement in postoperative pain control. Patients who have a history of chronic pain may require substantially increased doses of medication to achieve adequate postoperative pain control. For these patients, consultation of the acute pain service may be beneficial.

C. Enterotomy and Anastomotic Leak

Anastomotic leak is most commonly a delayed postoperative complication, occurring most often during the second postoperative week or, in some cases, up to a month following surgery. Although anastomotic leak presents later in the postoperative course, this does not exclude enterotomy or primary failure of the staple/suture line, both of which can present much earlier. Hypotension, tachycardia, low urine output, and peritoneal signs are all suggestive of a possible enterotomy or anastomotic leak.

When a leak is suspected, it can be further investigated with imaging. Computed tomography with PO contrast is the most common choice; however, fluoroscopy with either PO or rectal contrast is also an option, depending on the location of the suspected leak (Fig. 9.1).

1. Etiology

Multiple patient factors increase the risk of anastomotic leak, including male sex, obesity, coronary artery disease, pulmonary disease, diabetes, anticoagulation, decreased preoperative albumin, complications during the surgery, and high ASA score. The etiology of the anastomotic leak can vary. No difference has been found between the rates of anastomotic leakin open versus laparoscopic operations.