Trocar placement and port sites

🛠️ Key Structures - Tools of the Trade

• Trocar & Cannula: A trocar is a sharp-tipped obturator inserted through a hollow tube (cannula/port). The trocar is removed, leaving the cannula for instrument access.
• Primary Port Placement (for insufflation):
  • Veress Needle (Closed): "Blind" insertion, typically at the umbilicus or Palmer's point (left subcostal margin).
  • Hasson Technique (Open): Small infraumbilical incision, direct visualization of fascia, and suture placement before port insertion. ⚠️ Preferred in patients with prior abdominal surgery to reduce bowel injury risk.

⭐ To avoid the inferior epigastric artery, place lateral ports lateral to the rectus sheath. The vessel is located roughly one-third of the distance from the pubic tubercle to the ASIS.

📍 Anatomy - Abdominal Entry Points

Primary entry establishes pneumoperitoneum. Secondary ports are for instrumentation. Site selection is critical to avoid vascular and visceral injury.

• Secondary Port Placement:
  • ⚠️ Primary Goal: Avoid the inferior epigastric artery.
  • This vessel arises from the external iliac artery and courses superiorly on the deep surface of the rectus abdominis muscle.
  • 💡 Technique: Place secondary trocars under direct intra-abdominal visualization. Transillumination can identify superficial vessels but is unreliable for the deep epigastrics.

⭐ Injury to the inferior epigastric artery is a common, preventable complication. It typically occurs with lateral port placement and can cause a large, rapidly expanding rectus sheath hematoma.

📍 Clinical Correlations - Ports & Perils

• Primary Entry Risks (Umbilicus):

  • Most common site for initial access.
  • ⚠️ High risk of major vessel injury (aorta, IVC) in thin patients or with improper technique.
  • Risk of bowel injury, especially with prior midline surgery (adhesions).

• Safe Alternative Entry: Palmer's Point

  • Located in the left upper quadrant, 2-3 cm below the costal margin in the mid-clavicular line.
  • 💡 Preferred in patients with suspected periumbilical adhesions or obesity.

⭐ High-Yield: Injury to the inferior epigastric artery is a classic complication of lateral port placement. It arises from the external iliac artery and can cause significant retroperitoneal hematoma. Always transilluminate the abdominal wall before insertion.

• Common Complications:
  • Nerve Injury: Ilioinguinal/iliohypogastric nerves are at risk with low lateral ports, causing groin pain/numbness.
  • Port-Site Hernia: Increased risk with ports >10 mm if fascia is not closed.

⚡ Biggest Takeaways

• Umbilicus is the primary port site; initial entry via Veress needle (blind) or Hasson technique (open).
• Palmer's point (LUQ) is a safer alternative entry site in patients with prior midline surgery or obesity.
• Avoid the inferior epigastric artery during lateral port placement; it's the most commonly injured vessel.
• Primary trocar insertion carries the highest risk of catastrophic aortic, IVC, or bowel injury.
• Maintain CO2 pneumoperitoneum at 12-15 mmHg; higher pressures risk hemodynamic compromise.
• Insert all secondary ports under direct visualization to prevent iatrogenic injury.