Can paralytic ileus occur on the second postoperative day after Coronary Artery Bypass Grafting (CABG)?

Paralytic Ileus After Coronary Artery Bypass Grafting (CABG)

Yes, paralytic ileus can occur on the second postoperative day after CABG surgery, as gastrointestinal complications including paralytic ileus are recognized complications following cardiac surgery. 1

Incidence and Risk Factors

• Paralytic ileus is the most common gastrointestinal complication after cardiac surgery, accounting for approximately 36% of all abdominal complications following cardiopulmonary bypass 1
• The overall incidence of gastrointestinal complications after cardiac surgery is approximately 1.21%, with paralytic ileus occurring in a subset of these patients 2
• Risk factors that increase the likelihood of developing paralytic ileus after CABG include:
  • Extended cardiopulmonary bypass time (longer CPB time correlates with higher risk) 1
  • Valve surgery or combined procedures (higher risk compared to isolated CABG) 1
  • Low cardiac output states 2
  • Advanced age (>70 years) 2
  • Use of narcotic analgesics 3
  • Electrolyte imbalances 4
  • Use of intraaortic balloon pump 2

Pathophysiology

• The pathophysiology of post-CABG paralytic ileus is multifactorial:
  • Systemic inflammatory response syndrome (SIRS) triggered by cardiopulmonary bypass 5
  • Splanchnic hypoperfusion during and after surgery 2
  • Effects of anesthesia and opioid analgesics on gastrointestinal motility 3
  • Electrolyte disturbances, particularly hypokalemia 4

Clinical Presentation

• Symptoms typically develop within the first few postoperative days, including:
  • Abdominal distension 3
  • Absence of bowel sounds 3
  • Nausea and vomiting 3
  • Inability to tolerate oral intake 3
  • Delayed passage of flatus or stool 3

Management

• Regular evaluation and correction of electrolytes, particularly potassium 4
• Review and adjustment of analgesic regimen:
  • Minimize narcotic use by substituting with non-opioid alternatives like acetaminophen and NSAIDs when not contraindicated 4
  • Consider tramadol as an alternative to traditional opioids 4
• Nasogastric decompression for patients with significant nausea, vomiting, or abdominal distension 4
• Fluid management:
  • Isotonic dextrose-saline crystalloid maintenance fluids administered within a restrictive regimen 4
  • Balanced isotonic crystalloid replacement fluids containing supplemental potassium 4
• Early mobilization and ambulation to stimulate bowel function 4
• Nutritional support:
  • Providing controlled, comprehensive dietary intake once bowel function returns 6
  • Consider parenteral nutrition if unable to tolerate adequate oral intake for more than 7 days post-operatively 4

Monitoring and Complications

• Regular abdominal examinations to monitor for signs of resolution or worsening 7
• Vigilance for signs of more serious complications such as intestinal ischemia, which can present similarly but carries a much higher mortality risk 2
• Early consultation with the surgical team if symptoms persist beyond 3-4 days or if clinical deterioration occurs 7

Prevention

• Implementing blood conservation strategies to limit hemodilutional anemia 6
• Early mobilization when hemodynamically stable 4
• Minimizing opioid use in the postoperative period 3
• Maintaining adequate perfusion pressure during and after surgery 2

Prognosis

• Most cases of paralytic ileus after CABG resolve with conservative management within 3-5 days 3
• Prolonged ileus (>3 days) may require more aggressive intervention 3
• The overall mortality associated with gastrointestinal complications after cardiac surgery is approximately 34.1%, though isolated paralytic ileus typically has a better prognosis than other GI complications 2