Harrith M. Hasson
Table Of Contents
Harrith M. Hasson, MD
ADVANTAGES OF OPEN VERSUS CLOSED LAPAROSCOPY
Laparoscopy requires distention of the abdominal cavity with a suitable gas to create a clear space between the abdominal wall and abdominal contents, as well as the introduction of a lighted telescope into the abdominal cavity to visualize various organs and to perform different procedures.
Traditionally, laparoscopy has been performed using needles to introduce the gas and sharp trocars to introduce the laparoscope into the abdominal cavity. The abdomen is first insufflated with a needle inserted blindly through the abdominal wall. After abdominal distention, a small skin incision is made, and a cannula bearing a sharp trocar is thrust forcibly against the remaining layers of the abdominal wall into the peritoneal cavity. The blind introductions of the needle and trocar into the peritoneal space are guided by tactile sensations. The sharp trocar is withdrawn and replaced by the scope, and the appropriate endoscopic procedure is performed. At the end of the procedure, the cannula and scope are removed. The skin wound is approximated, but the fascial gap is not repaired because it is not accessible. It is becoming increasingly clear, however, that the use of such sharp instruments is not necessary for performing laparoscopy, and on some occasions, it is undesirable.
Laparoscopy can be easily performed with the use of a minilaparotomy incision. This variation is called open laparoscopy. The difference between open and traditional closed laparoscopy relates specifically to the method of abdominal entry, the sequence of entry/insufflation, and the type of abdominal wall closure. All other aspects of laparoscopy remain unchanged.
In open laparoscopy, the abdomen is first entered through a minilaparotomy incision developed under visual control. A specific cannula carrying a blunt obturator then is introduced through the incision into the abdominal cavity. Gas is insufflated directly through the cannula. The obturator is removed and replaced with the laparoscope, and the appropriate endoscopic procedure is carried out. When the procedure is completed, the cannula and scope are removed and the abdominal wall is closed in layers.1-3
The abdominal cavity may be entered through a minilaparotomy incision at any location on the anterior abdominal wall.4-6 For open laparoscopy, however, the lower border of the umbilicus is the preferred site of entry. In this location, the abdominal wall has the fewest layers, since it consists of skin fused with linea alba, transversalis fascia, preperitoneal adipose tissue, and peritoneum. The area is devoid of subcutaneous adipose tissue, Camper's fascia, and any muscles. It may be considered a window through which open laparoscopy can be most easily performed7 (Fig. 1). These unique anatomic relations result from developmental events that occur at the time of birth and shortly thereafter. Four ligaments resulting from closure of functional fetal structures attach to the inferior border of the umbilical ring and pull the skin against the deep fascia while the once-functional vessels and ducts retract and become fibrotic. The round ligament arises from the obliteration of the umbilical vein, the median umbilical ligament evolves from closure of the urachus, and the medial umbilical ligaments represent the obliterated umbilical arteries and allantoic duct (Fig. 2). In some subjects, the transversalis fascia is highly condensed into a strong layer called the fascia umbilicalis or Richet's fascia.8 The disposition of the umbilical ligaments about the umbilical ring, a fibrotic opening n the linea alba, and the presence and position of Richet's fascia are subject to wide individual variations,8 as shown in Figure 2. These variations influence the ease with which open laparoscopy is performed. Technical difficulty also is related to the tonal strength of the abdominal wall supports in the umbilical region. Other factors that increase technical difficulty include fibrosis and adhesions secondary to previous surgery or inflammation. Marked obesity per se has no effect on technical difficulty or cosmetic result. The larger incision (not to exceed 2.5 cm) that is needed to facilitate exposure of the linear alba can be made to disappear in one of the umbilical folds.
Surgical incisions made along or parallel to the lines of Langer,9 which define natural cleavage lines of the skin, heal better than incisions that cross those lines.10 In the area of the umbilicus, the lines of Langer are aligned vertically, giving a sunburst appearance. The use of vertical laparoscopy incisions in the area of the umbilicus results in a superior cosmetic scar when compared with transverse laparoscopy incisions.11 Furthermore, the use of a vertical incision consistently exposes the position of fascial attachment to the skin (see Fig. 1). The arterial blood supply of the umbilical region comes from the inferior epigastric, superior epigastric, and superficial epigastric vessels. These arteries form a communicating arcade around the umbilicus, which is accompanied by the periumbilical venous plexus (Fig. 3).
Standard instruments needed for open laparoscopy include two Allis clamps, a knife handle with a small blade, a straight scissors, two Kocher clamps, two small hemostats, a dissecting tissue forceps with teeth, and a short needle holder. S-shaped retractors formed with two retracting ends are used to expose the small operative field (Fig. 4). One of the retracting ends is acutely curved, and the other is more flattened. The curved end is used for retracting the superficial layers of the abdominal wall as it is anchored beneath the skin. The flatter end is more appropriate for retracting the deeper layers because it requires less space for insertion. The use of small, strong needles attached to sutures of adequate tensile strength is recommended to avoid breakage and to enhance the ease of manipulation.
Standard laparoscopic equipment is used, with the exception of the primary cannula and pneumoperitoneum needles. The open laparoscopy cannula is fitted with a cone-shaped sleeve that moves freely over the shaft of the cannula. The cone is locked into position along the shaft using a metal screw. A rubber cap seals the cone. V-shaped suture holders are mounted on the instrument. A blunt obturator replaces the conventional sharp trocar (Fig. 5). Pneumoperitoneum needles are not used.
Several instrument companies offer disposable and reusable blunt-tipped open laparoscopy cannulas with suture holders mounted on the cone or with a distal balloon.
Safe and effective performance of open laparoscopy is based on four tenets:
When satisfactory anesthesia has been achieved, the surgeon applies two Allis clamps on the lateral margins of the umbilicus and makes a vertical incision at the 6-o'clock position of the lower umbilical margin, extending inferiorly for a distance of 1 to 2.5 cm (Fig. 6). The Allis clamps are repositioned on the skin edges to be used for retraction. Closed scissors are introduced into the incision, and the blades are separated several times to dissect connective tissue fibers found between the skin and deep fascia. The surgeon directs a Kocher clamp toward the upper angle of the incision and grasps the inferior margin of the umbilical ring where the fascia is fused with the skin. The surgeon lifts and everts the fascia and applies a second Kocher clamp on it more inferiorly (Fig. 7). The fascia is clearly identified by separating it from surrounding fibrous, adipose, and areolar tissue with blunt or sharp dissection. The first Kocher clamp can be reapplied on the fascia to realize a more secure purchase, as indicated.
The surgeon raises the deep fascia with the Kocher clamps and incises the fascia carefully between the clamps while maintaining fascial elevation. Raising the fascia separates the abdominal wall from the bowel and omentum and minimizes the possibility of inadvertent damage during fascial incision. The initial size of incision need not exceed 0.5 cm. The incision then is enlarged using a spreading hemostat. Usually, the peritoneum is entered by the spreading hemostat. Otherwise, the flat end of one S-shaped retractor is introduced into the incisional gap and is pressed against the peritoneum for abdominal entry (Fig. 8). The surgeon passes a suture through each fascial edge and tags it. The S-shaped retractor lodged within the incision acts as a backstop to the needle. The second S-shaped retractor then is placed through the fascial gap into the peritoneal cavity, and the abdominal wall is raised with both retractors to confirm peritoneal entry by viewing the bowel and omentum. If the surgeon discovers that the abdominal cavity had not been entered, the surgeon identifies and retracts the rectus muscle, exposes the peritoneum, and enters it with a thrust of a small hemostat. The hemostat is opened inside the peritoneal cavity, and a retractor is placed in the abdomen between the open jaws of the hemostat. The hemostat is removed, and the other retractor is applied on the opposite side. Occasionally, abdominal entry is not possible with the previously described procedures because of the presence of a well-developed Richet's fascia. In this case, the surgeon should lift Ricket's fascia and peritoneum with two hemostats and incise them carefully to avoid nicking the small bowel. In any case, the surgeon must confirm peritoneal entry through visualization of the small bowel or omentum.
The surgeon prepares the open laparoscopy cannula for insertion by sliding the cone sleeve over the shaft and locking the cone in a position consistent with the individual thickness of the abdominal wall. The cannula then is introduced between the retractors into the abdominal cavity (Fig. 9). The fascial tag sutures are held tensely upward and threaded into the V-shaped suture holders (Fig. 10). This maneuver fixes the cannula on the abdominal wall and pulls the fascia against the cone to prevent escape of the gas (Fig. 11). Gas insufflation is initiated during threading of the fascial tag sutures into the suture holders. The blunt obturator is removed to permit a rapid flow of the gas.
The surgeon introduces the laparoscope, with or without an attached camera, through the open laparoscopy cannula and performs the intended procedure. When the endoscopic procedure is completed, the surgeon deflates the distended peritoneal cavity, withdraws the cannula, and closes the abdominal wall in two layers. The fascial tag sutures are used to approximate the fascia. The surgeon positions the sutures in parallel alignment (Fig. 12), ties a square knot on one side (Fig. 13), pulls the tied suture against the fascia, and ties a second knot on the opposite side of the fascia (Fig. 14). The skin is approximated loosely.
Although open laparoscopy is a simple operation, there are several pitfalls that increase technical difficulty. These are outlined in Table 1.
Other Procedures Using Similar Concepts
Several operations applying similar concepts of abdominal entry for laparoscopy have been proposed. These procedures use a standard laparoscopic cannula, not the open laparoscopy cannula. The modified techniques of open laparoscopy are safe and effective to the extent that they observe the basic tenets of the procedure and succeed in providing an airtight seal around the cannula. Additionally, care must be exercised while introducing the cannula into the abdomen without a protective blunt obturator to avoid internal injury by the sharp edge of the bare cannula.
Examples of methods described to block escape of the gas around a standard cannula include using a purse-string suture in the fascia (with or without a rubber tube choker)13, 14 or in the subcutaneous tissue,15 and applying towel clips,16-18 Allis clamps,19 or suture20 to the skin and subcutaneous tissue surrounding the cannula.
Certain misconceptions exist with regard to open laparoscopy:
|ADVANTAGES OF OPEN VERSUS CLOSED LAPAROSCOPY|
A consensus is emerging that most major complications of laparoscopy, defined as those leading to death or further surgery, occur as a result development of the pneumoperitoneum and blind insertion of the primary trocar, regardless of the complexity of type of laparoscopic procedure that follows.28-31 The elimination of these two potentially dangerous procedures is the main objective of open laparoscopy. Published reports of complications associated with closed laparoscopy indicate that most abdominal organs and structures have been punctured by pneumoperitoneum needles or sharp trocars.2 Misplacement of the needle and inappropriate gas insufflation has also caused emphysema of the subcutaneous tissues, the fascial compartments, and the omentum.2
For open laparoscopy, the rate of bowel injury in 26,178 patients was 0.08%, ranging from 0.03% in studies using the open method in all cases to 0.5% in those dealing exclusively with high-risk patients.2 There was one case report of a serosal bowel injury in a 2-year-old child who underwent an open laparoscopy procedure in which a standard bare 5-mm cannula and a purse-string suture were used. The suture caught the bowel. The injury was repaired, and the procedure continued as usual.32 There was one case of a major vessel injury with open laparoscopy in 26,178 patients, giving a rate of 0.004%. Occurrences of gas embolism or other visceral damage have not been reported.2 These complication rates compare favorably with those reported with closed laparoscopy.
Unlike closed laparoscopy, the use of open laparoscopy is not contraindicated by a history of previous abdominal surgery or by the presence of abdominal masses or marked obesity. Furthermore, because of increased safety, open laparoscopy can be used in clinical situations in which the potential risk of performing closed laparoscopy is greater than the potential benefits.
Consistency of Success
Failed attempt is a recognized problem of closed laparoscopy. Marked obesity or the development of significant abdominal wall emphysema (from inappropriate insufflation) may prevent the surgeon from completely traversing the abdominal wall with the needle or trocar. The presence of abdominal adhesions or metastatic disease also may prevent the surgeon from localizing the main compartment of the peritoneal cavity. These problems are less likely to occur with open laparoscopy because the abdomen is entered through an incision developed in a naturally occurring anatomical window, and gas is insufflated only after successful entry has been confirmed. The rate of failed attempts with open laparoscopy was 0.02% (two failures in 11,499 patients).2 Both patients had severe adhesions that prevented entry into the abdomen.
Correct Closure of the Abdominal Wall
In closed laparoscopy, the fascial tear induced by the sharp trocar is not accessible and therefore not repaired. Postoperative incisional hernias thus could develop through the unapproximated fascial gap. This complication has been reported frequently.2 Conversely, the fascial incision in open laparoscopy is clearly accessible and easily approximated. Routine closure of the fascia minimizes the possibility of postoperative herniation. The rate of umbilical hernia after open laparoscopy was 0.06% in 11,210 patients.2
Alleviation of Physician Stress
For many surgeons, the process of inserting needles and trocars into a closed abdomen is associated with a certain amount of stress. Supervising a novice while performing closed laparoscopy can produce even greater anxiety. Open laparoscopy frees the surgeon of such unnecessary stress because it uses a familiar and more predictable surgical technique.