Postoperative Abdominal Distension After Lower Segment Cesarean Section
Postoperative abdominal distension after LSCS is most commonly caused by postoperative ileus, with key risk factors including opioid analgesia, significant blood loss (>1000 mL), blood transfusion, general anesthesia, and preeclampsia. 1
Primary Mechanism: Postoperative Ileus
The predominant cause of post-LSCS distension is postoperative ileus (POI), which occurs through three main pathways 2:
- Neurogenic mechanisms: Disruption of sympathetic/parasympathetic pathways to the gastrointestinal tract during surgery 2, 3
- Inflammatory response: Enteric molecular inflammation with leucocyte recruitment into the intestinal muscularis, impairing neuromuscular function 2
- Pharmacological factors: Opioid administration for postoperative pain control significantly reduces propulsive GI motility 2, 3
Specific Risk Factors for Post-LSCS Distension
High-Risk Surgical Factors
- Blood loss >1000 mL: Strongest predictor after multivariable analysis 1
- Blood transfusion: Independently associated with ileus development 1
- General anesthesia exposure: Significantly increases risk compared to neuraxial anesthesia 1
- Hysterectomy at time of cesarean: Associated with prolonged ileus 1
- Classical hysterotomy or midline vertical incisions: Higher risk than standard transverse approaches 1
Medical Comorbidities
- Preeclampsia: Identified as independent risk factor for postcesarean ileus 1
- Magnesium sulfate exposure: More common in cases developing distension 1
Medication-Related Causes
- Opioid analgesia in labor: Increases risk 4.67-fold for developing acute colonic pseudo-obstruction (ACPO) 4
- Meperidine for postoperative pain: Specifically implicated in adynamic ileus 5
Acute Colonic Pseudo-Obstruction (Ogilvie Syndrome)
A rare but serious variant occurring in approximately 1 in 800 cesarean sections 4:
- Clinical presentation: Severe colicky pain, vomiting, and marked abdominal distension occurring immediately or within 2 days postoperatively 5
- Pathophysiology: Functional ileus of the distal large bowel related to hormonal, autonomic, and metabolic changes from pregnancy and childbirth 4
- Danger: Insidious onset can lead to delayed diagnosis with risk of bowel ischemia, perforation, and sepsis 4
Other Contributing Factors
Perioperative Fluid Management
- Fluid overload: Increases risk of cardiovascular work and pulmonary edema, potentially contributing to ileus 6
- Hypovolemia: Unstable hemodynamic status from significant peripartum hemorrhage predisposes to adynamic ileus 5
Surgical Technique Factors
- Overt bowel manipulation: Direct handling increases inflammatory response 5
- Operative duration: Longer, more complex surgeries correlate with higher ileus risk 1
Critical Pitfalls to Avoid
Do not dismiss early distension as "normal postoperative gas" - ACPO can progress rapidly to bowel perforation if unrecognized 4. Obtain CT imaging if distension is severe or accompanied by severe colicky pain and vomiting within 48 hours 5.
Minimize opioid exposure - The ERAS Society strongly recommends multimodal analgesia with intrathecal morphine 50-100 μg, paracetamol, and NSAIDs to reduce systemic opioid requirements that drive ileus 6, 7.
Maintain euvolemia - Both fluid overload and significant blood loss contribute to distension; the ERAS Society provides strong recommendations for perioperative euvolemia 6.
Prevention Strategies Based on Guidelines
- Neuraxial anesthesia preferred: Regional techniques reduce ileus risk compared to general anesthesia 7, 1
- Early feeding: Regular diet within 2 hours after cesarean delivery 7
- Early mobilization: Recommended to facilitate bowel function recovery 7
- Avoid routine nasogastric decompression: Plays no preventive role and may increase complications 3