Overview
Definition:
Colonic perforation after colonoscopy refers to an iatrogenic injury to the colonic wall occurring during or immediately after a colonoscopic procedure
Laparoscopic repair is a minimally invasive surgical approach to manage such perforations.
Epidemiology:
The incidence of colonic perforation following colonoscopy is estimated to be between 0.02% and 0.2% of procedures, with higher rates in diagnostic colonoscopies compared to screening
Risk factors include polypectomy, older age, diverticulosis, and difficult colonoscopies
Laparoscopic repair is increasingly favored for contained perforations.
Clinical Significance:
Colonic perforation is a serious complication that can lead to peritonitis, sepsis, and death if not managed promptly and appropriately
Early diagnosis and surgical intervention are crucial for favorable outcomes, making this a high-yield topic for surgical trainees preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Sudden onset of severe abdominal pain
Abdominal distension
Fever and chills
Nausea and vomiting
Tachycardia and hypotension in severe cases
Signs of peritonitis may develop rapidly.
Signs:
Abdominal tenderness, guarding, and rebound tenderness
Absent bowel sounds or high-pitched tinkling sounds
Palpable abdominal masses in cases of contained perforation
Signs of hypovolemic shock if significant bleeding or fluid loss occurs.
Diagnostic Criteria:
Diagnosis is typically based on a high index of suspicion in a patient presenting with abdominal pain after a recent colonoscopy, confirmed by imaging
Clinical signs of peritonitis are highly suggestive
No specific laboratory criteria, but inflammatory markers may be elevated.
Diagnostic Approach
History Taking:
Detailed history of the colonoscopy: date, indication, any difficulties encountered, and immediate post-procedure symptoms
Onset, character, and severity of abdominal pain
Presence of fever, nausea, vomiting
Past surgical and medical history.
Physical Examination:
Thorough abdominal examination assessing for tenderness, rigidity, guarding, rebound tenderness, and bowel sounds
Assessment of vital signs for signs of shock or sepsis
Digital rectal examination may reveal gross blood or performation signs.
Investigations:
Plain abdominal X-ray (supine and erect) to detect free air under the diaphragm
CT scan of the abdomen and pelvis is the investigation of choice for accurate localization of perforation, assessment of free air and fluid, and identifying the extent of contamination
Routine blood tests: CBC (leukocytosis), electrolytes, renal function tests, coagulation profile, and liver function tests
Blood cultures if sepsis is suspected.
Differential Diagnosis:
Other causes of acute abdomen post-colonoscopy: mesenteric ischemia, appendicitis, diverticulitis, peptic ulcer perforation, bowel obstruction, inflammatory bowel disease flare-up.
Management
Initial Management:
Immediate resuscitation with intravenous fluids and broad-spectrum antibiotics
Nasogastric tube insertion for decompression if bowel obstruction or ileus is present
Pain management with analgesics
Correction of electrolyte imbalances.
Surgical Management:
Laparoscopic repair is the preferred approach for contained perforations, especially in stable patients
It involves identifying the perforation site, performing thorough peritoneal lavage, and repairing the defect with sutures or a patch (e.g., omental patch)
For large, uncontrolled, or extensively contaminated perforations, open laparotomy with resection and primary anastomosis or diversion (colostomy) may be necessary
Diverting loop ileostomy or colostomy may be considered for distal colonic perforations.
Supportive Care:
Close monitoring of vital signs, abdominal examination, and fluid balance
Nutritional support, often initiated with parenteral nutrition initially, progressing to enteral feeding as bowel function returns
Intensive care unit admission may be required for hemodynamically unstable patients or those with sepsis.
Complications
Early Complications:
Peritonitis, intra-abdominal abscess formation, sepsis, wound infection, prolonged ileus, anastomotic leak (if primary anastomosis is performed), bleeding.
Late Complications:
Adhesions leading to bowel obstruction, incisional hernia, stoma-related complications (if a stoma was created), chronic pain syndrome.
Prevention Strategies:
Careful technique during colonoscopy, particularly during insufflation and withdrawal
Avoiding excessive force
Using CO2 insufflation for faster absorption and reduced patient discomfort
Careful assessment and management of difficult procedures, such as those with diverticular disease or adhesions
Adequate bowel preparation
Patient selection and informed consent regarding risks.
Prognosis
Factors Affecting Prognosis:
Time to diagnosis and surgical intervention, extent of peritoneal contamination, patient's overall health status, presence of comorbidities, and the specific technique of repair
Early laparoscopic intervention in contained perforations generally leads to better outcomes.
Outcomes:
With prompt diagnosis and appropriate management, most patients can achieve a full recovery
Mortality rates are significantly lower for contained perforations managed with early laparoscopic repair compared to those presenting with generalized peritonitis and delayed treatment
Outcomes for open surgery or re-do surgery are generally poorer.
Follow Up:
Postoperative follow-up includes monitoring for signs of complications such as infection or anastomotic leak
If a stoma was created, education on stoma care and planning for its eventual closure
Regular clinic visits to assess recovery and address any long-term issues
Patients should be advised to report any new or worsening abdominal symptoms.
Key Points
Exam Focus:
Recognize symptoms of post-colonoscopy perforation
Understand the role of CT abdomen/pelvis
Differentiate between contained and free perforations
Know indications for laparoscopic vs
open surgery and when to consider stoma formation
Management of sepsis and peritonitis.
Clinical Pearls:
Always consider iatrogenic perforation in patients presenting with acute abdomen post-colonoscopy, even days later
CT scan is superior to plain X-ray for diagnosing and localizing the perforation
Laparoscopy is preferred for stable patients with contained perforations, offering faster recovery and less morbidity
Prompt antibiotics and fluid resuscitation are vital.
Common Mistakes:
Delaying diagnosis due to attributing symptoms to post-procedural discomfort
Inadequate workup when perforation is suspected
Opting for conservative management of a free perforation
Performing primary anastomosis in a grossly contaminated abdomen without adequate lavage or proximal diversion
Underestimating the severity of sepsis.