For laparoscopic surgery, insufflation of the peritoneal cavity and establishment of entry ports must be completed. To achieve insufflation, the surgeon must first gain safe access to the peritoneal cavity. Several techniques for gaining access to the peritoneal cavity have been described involving various devices designed to minimize entry-related injury and complications. After pneumoperitoneum has been established, ports of entry and reentry are needed to allow retention of intraperitoneal gas and swift instrument exchange. To that end, different types of trocars have been developed and continue to be refined to improve ease of placement and use. In this chapter, we review and describe the various available techniques and devices for accessing the peritoneum and maintaining access ports during laparoscopic surgery.
Establishing access to the peritoneal cavity
In 1938, Hungarian surgeon Janos Veres invented a spring-loaded needle that consisted of a beveled-point cannula with an incising capability (VER-FLOW, Sterylab, Milan, Italy) ( Fig. 10.1 ). Inside the outer cannula, a blunt-tipped inner stylet would spring forward when it encountered a sudden decrease in tissue resistance. The decrease in tissue resistance correlates with entry into the peritoneal cavity. The deployment of the blunt inner stylet renders the needle into a blunt-tipped device that can safely come into contact with intraperitoneal viscera. Although Veres did not use the device for that purpose, the needle quickly gained popularity as the preferred method for establishing pneumoperitoneum. The modern-day Veress needle has an external diameter of 2 mm and comes in lengths varying from 12 to 15 cm.
Points of insertion
In the virgin abdomen, the umbilicus is an excellent site for needle insertion owing to the short distance between skin and peritoneum. Disadvantages include a short distance to the abdominal viscera and proximity to the great vessels. Two areas of resistance are typically felt as the Veress needle advances, representing the abdominal wall fascia and the peritoneum.
Alternative points of insertion could be used after failure to establish safe access in extremely thin or obese patients, in the presence of an umbilical hernia, or in a patient with prior midline or periumbilical incisions with expected midline adhesions. These alternative points of insertion can be used routinely based on surgeon comfort and preference.
Palmer’s point ( Fig. 10.2 ) is the point on the midclavicular line below the left subcostal margin that can be used as a point of Veress needle insertion. A mirror image point of Palmer’s point on the right side also can be used. These points should be avoided with known hepatosplenomegaly, prior left or right upper quadrant surgery, or portal hypertension. Gastric decompression before peritoneal access is essential to help reduce the risk of gastric and duodenal injury. Minor lacerattions to the liver may occur in up to 5% of these entries, but reports suggest that most, if not all, of these injuries may be managed conservatively.
An uncommon point of insertion is the ninth or tenth intercostal space along the anterior axillary line. This point has the advantage of the parietal peritoneum’s natural attachment to the lower surface of the rib. Entry near the lower surface of the rib should be avoided, however, to avoid injury to the neurovascular structures. Pneumothorax, as well as injury to the stomach, liver, or spleen, has been reported with this approach. In the gynecologic literature, alternative access points include the transuterine and trans–cul de sac paths, both with good results.
Although some authors advocate lifting or stabilizing the anterior abdominal wall (such as with towel clips or with a manual rectus abdominis grasp) before Veress needle insertion, others downplay the necessity of the maneuver. Similarly, some surgeons may place the patient in slight Trendelenburg position prior to supraumbilical needle insertion. Some surgeons prefer a skin incision before needle insertion. Angling of the needle at the time of insertion to 45 degrees in patients with a body mass index of less than 30 kg/m 2 can help avoid major vascular injury.
Safe placement of a Veress needle into the peritoneal cavity can be confirmed by the following series of maneuvers:
Measurement of the skin-to-peritoneum distance on preoperative imaging to help estimate the distance of needle advancement at the point of entry.
Aspiration through the Veress needle after placement to confirm absence of vascular or visceral injury before insufflation. Blood or debris may represent insertion into vascular or enteric structures, respectively.
Performance of the saline drop test, which allows a drop of saline to passively pass through the lumen of the needle. A quickly disappearing saline drop confirms intraperitoneal placement.
Confirmation of a starting pressure of 9 mm Hg or lower at entry to confirm intraperitoneal placement.
Performance of the advancement test, which allows the practitioner to make an assessment of whether they are through the preperitoneal space. Advancement of the needle approximately 1 cm without resistance suggests access to the peritoneal space.
Other less commonly used maneuvers include reliance on the “hiss” sound test to confirm correct placement and the use of ultrasonography to identify possible adhesions before needle placement attempts.
The Veress needle technique can be successfully performed to gain peritoneal access over 90% of the time, even in patients with prior abdominal surgeries, particularly if Palmer’s point access is used. Known complications include visceral or vascular injury, which occurs less than 0.5% of the time, and abdominal wall bleeding. An exceedingly rare, though potentially fatal, complication is a carbon dioxide (CO 2 ) embolism, which can occur if the Veress needle is placed into a vessel. This may manifest as decreasing end-tidal CO 2 , decreasing oxygen saturation, and hemodynamic compromise and requires prompt discontinuation of insufflation.
Enhancements to a standard Veress needle have been described. These include a fitted sensor to detect the position of the tip of the needle as it enters the peritoneal cavity and a wider optical Veress needle that allows a semirigid minilaparoscope, allowing insertion of the needle under direct vision. While this approach is not commonly used, studies have demonstrated that these types of Veress needles can be inserted expeditiously without increased rates of complications.
Open access: Hasson technique
Harrith M. Hasson first described the open laparoscopy technique in 1971. The open technique ( Fig. 10.3 ) is arguably the safest in the setting of prior abdominal surgery and adhesions. It can also be useful in pregnant patients or in extremely thin adults.
The steps of the Hasson technique are as follows:
A skin incision is made in the desired location.
The subcutaneous tissues are bluntly separated with adequate hemostasis.
The fascia is incised, and stay sutures are placed on the divided fascial edges.
The peritoneum is grasped and incised sharply.
The surgeon’s finger is used to confirm bowel safety.
The Hasson trocar is placed through the incision, and the stay sutures are used to secure the port in place.
Pneumoperitoneum is established through the port.
The fascia is closed at the conclusion of the surgery.
A balloon trocar can be used with the open technique as an alternative to the Hasson trocar. After trocar placement, the designated amount of air is injected into the internal retention balloon. An external sliding foam pad is positioned to maintain an airtight seal at the port site. The Hasson technique is generally considered a safe option, with a complication incidence as low as 0.2%. However, its universal use is limited by the time required to accomplish access, particularly in obese patients.
Direct trocar entry
Direct trocar entry was first described in 1978 by Dingfelder. The technique relies on the translucency of the dilating tip, allowing trocar introduction under direct vision with a laparoscope in place. The safety of the technique requires sound familiarity with abdominal wall anatomy and comfort with the appearance of each layer when viewed through an optical trocar and a gasless peritoneal cavity. Some reported complications include bowel injury related to entry in 0.11% of patients and vascular injury in 0.01% of patients, with other series reporting higher complication rates. Other studies showed fewer complications with direct trocar entry than with Veress needle entry, indicating that direct trocar entry is a safe alternative to Veress needle insertion and perhaps is an underused technique. Its advantages also include the short time required for completion and the avoidance of complications related to blind insufflation. Yet a survey of urologic surgeons revealed it is the least commonly used entry technique in urologic laparoscopic surgery.
The steps for direct trocar entry are as follows:
The skin is incised below the umbilicus or in the subcostal region.
The abdominal wall is lifted with clamps or with the surgeon’s hand.
The optical trocar is inserted under direct vision toward the pelvis with a laparoscope in place. Each layer is identified in sequence under vision.
Insufflation is started through the trocar.
The blade of the trocar is removed, and the laparoscope is reintroduced.
Typically, the hand-port access method is used for surgeons who may not feel comfortable with the aforementioned access techniques. It involves using an open technique to gain access to the peritoneum. Following this, a hand-port is placed and used to establish pneumoperitoneum by placing a blunt trocar through the hand-port device. Afterwards, the remaining ports may be placed, with the surgeon’s hand providing protection and guidance for the remaining access devices. This method of obtaining access is used infrequently.
Indirect laparoscopic access
Indirect access into the peritoneal cavity is typically used for secondary trocar placement after peritoneal insufflation has been accomplished by one of the aforementioned techniques. A variety of disposable and reusable trocars can be used for that purpose.
A laparoscopic trocar (also known as a port) is a hollow cylindric device that facilitates repeated access into the insufflated peritoneal cavity while maintaining a seal via an external valve mechanism. Most trocars also have a connector device for attachment to insufflation tubing. Each trocar is constructed of an outer cannula (or sheath) and an inner obturator for initial placement. Trocars typically fall into two categories: cutting (axial) and dilating (radial). Cutting trocars have a blade that is used to pass through the fascial layer. Cutting trocars have fallen out of favor because of increased risk of visceral or vascular injury. They also result in a larger fascial defect and thus are more likely to require fascial closure. Dilating trocars typically include a blunt-tipped obturator that allows insertion while resulting in a fascial defect that is smaller than half the diameter of the outer cannula, which allows avoidance of fascial closure in most situations. However, we recommend digitally examining the fascial defect of each trocar site (even those belonging to a dilating trocar) at the end of the procedure to assess the need for fascial closure.
Reusable metal trocars
Reusable metal trocars (Girish Surgical Works, Mumbai, India) ( Fig. 10.4 ) have a stainless-steel trumpet valve with an insufflation port. The valve ensures no gas loss after insufflation. The ports have easily detachable sleeves for expeditious replacement in case of damage or soiling. These ports are relatively inexpensive and are considered economical because they can be sterilized and reused.