Describe the different techniques of creating pneumoperitoneum during laparoscopic surgery.

Techniques for Creating Pneumoperitoneum

The various methods for creating pneumoperitoneum can broadly be categorized into closed, open, and direct/optical entry techniques. Each approach has distinct characteristics, advantages, and disadvantages that influence a surgeon's choice based on patient factors, surgeon experience, and specific surgical requirements.

1. Veress Needle Technique (Closed Technique)

The Veress needle technique is arguably the most widely used and traditional method for establishing pneumoperitoneum.

• Procedure: A small skin incision is made, typically at the umbilical crease. A spring-loaded Veress needle, which has a blunt inner obturator that retracts to expose a sharp tip when encountering resistance and springs forward to protect organs once inside a cavity, is inserted "blindly" through the abdominal wall. The surgeon often lifts the abdominal wall to increase the distance from underlying organs. Correct intra-abdominal placement is verified by various tests, such as the hanging drop test, aspiration test, or saline injection test, and confirmed by low initial insufflation pressures. Carbon dioxide gas is then insufflated into the peritoneal cavity to create the pneumoperitoneum, typically to a pressure of 12-15 mmHg.
• Advantages:
  • Cost-effective and requires minimal equipment.
  • Relatively quick to perform for experienced surgeons.
  • Small skin incision.
• Disadvantages:
  • Blind insertion carries a risk of injury to major vessels or viscera (e.g., bowel, bladder, aorta). Studies suggest that a significant percentage of major complications in laparoscopy are related to initial blind access.
  • Risk of preperitoneal insufflation or gas embolism.
• Indications: Generally preferred in patients without a history of previous abdominal surgeries where adhesions are less likely.

2. Hasson Technique (Open Technique)

The Hasson technique, also known as open laparoscopy, was developed to mitigate the risks associated with blind entry.

• Procedure: A small incision (typically 1-2 cm) is made, usually at the umbilicus. The abdominal wall layers (skin, subcutaneous tissue, fascia) are dissected bluntly or sharply under direct visualization until the peritoneum is exposed. The peritoneum is then carefully incised, allowing direct visualization of entry into the abdominal cavity. A specialized blunt-tipped Hasson cannula, often secured with fascial sutures, is then inserted. Carbon dioxide is insufflated through this cannula.
• Advantages:
  • Direct visualization of abdominal wall layers minimizes the risk of visceral and vascular injuries during entry.
  • Considered safer for patients with previous abdominal surgeries due to the potential for adhesions, as it allows for meticulous dissection through scar tissue.
  • Reduced risk of gas embolism and preperitoneal insufflation.
• Disadvantages:
  • Requires a slightly larger incision compared to the Veress technique, potentially increasing the risk of wound complications and port-site hernia.
  • Can be more time-consuming for initial access.
  • Risk of gas leakage around the cannula if not properly sealed.
• Indications: Often preferred in patients with a history of prior abdominal surgeries, suspected adhesions, or in obese patients where anatomical landmarks might be obscured.

3. Direct Trocar Insertion (DTI)

The direct trocar insertion technique involves inserting the first trocar directly into the abdominal cavity without prior insufflation via a Veress needle.

• Procedure: After a small skin incision, a sharp trocar (often shielded) is inserted directly into the peritoneal cavity with a controlled, continuous twisting motion, without prior pneumoperitoneum. Entry is typically confirmed by a palpable "pop" as the trocar passes through the fascia and peritoneum, followed by immediate insertion of the laparoscope to visualize the abdominal cavity. Insufflation is then initiated.
• Advantages:
  • Faster technique than Veress needle as it eliminates the insufflation step before trocar insertion.
  • Reduces the number of "blind steps" compared to the Veress technique.
  • Some studies suggest it has a lower rate of insufflation-related complications like gas embolism.
  • Immediate recognition of any injury upon camera insertion.
• Disadvantages:
  • It is still a blind technique until the camera is inserted, carrying a risk of injury, especially if the abdominal wall is not adequately elevated or if there are underlying adhesions.
  • Requires significant surgeon experience and skill.
• Indications: Can be used as an alternative to the Veress needle in selected patients, particularly by experienced laparoscopic surgeons.

4. Optical Trocar Insertion

Optical trocars are specialized devices designed to allow visual confirmation during abdominal wall penetration.

• Procedure: An optical trocar, which incorporates a camera or fiber-optic light source, is inserted through a small skin incision. As the trocar advances, the surgeon can visualize the layers of the abdominal wall in real-time on a monitor, ensuring safe entry into the peritoneal cavity. Some optical trocars are bladed, while others are blunt or radially expanding. Once inside, insufflation can commence.
• Advantages:
  • Provides direct visual feedback during entry, significantly reducing the risk of injury to underlying structures, especially in complex cases or patients with altered anatomy (e.g., morbid obesity, previous surgeries).
  • Enhanced safety and precision.
• Disadvantages:
  • Requires specialized and more expensive equipment.
  • May require a slightly larger incision compared to the Veress needle.
• Indications: Particularly useful in patients with a high risk of adhesions, obesity, or where there is a concern for occult pathology at the entry site.

Comparative Overview of Techniques

The choice of technique often depends on a surgeon's preference, experience, and specific patient characteristics. There is no single universally superior method, and each has its own risk-benefit profile.

Technique	Entry Type	Key Feature	Primary Advantage	Primary Disadvantage
Veress Needle	Closed/Blind	Spring-loaded needle for gas insufflation	Minimal incision, quick for experienced users	Blind entry, risk of visceral/vascular injury
Hasson Technique	Open/Direct Visualization	Dissection of layers, blunt trocar insertion	Direct visualization, safer with adhesions	Larger incision, potentially more time-consuming
Direct Trocar Insertion	Blind (until camera)	Trocar inserted without prior insufflation	Faster access, immediate injury recognition	Still a blind technique, requires skill
Optical Trocar	Visualized	Camera within trocar for real-time visualization	Direct visualization of abdominal layers, enhanced safety	Higher cost, specialized equipment