In the “closed” laparoscopic access technique, cannulas can be inserted either after the successful creation of a pneumoperitoneum or without previously instilling intraperitoneal gas, also referred to as direct insertion. With open laparoscopy, there may be less risk of injury to the major blood vessels such as the aorta, inferior vena cava, and common iliacs. Open laparoscopy cannot prevent all insertion accidents because intestine can be entered inadvertently no matter how small the incision. There is little evidence that a pneumoperitoneum is necessary, at least in the absence of preexisting abdominal wall adhesions. In women with no previous surgery, the primary puncture can be performed with a trocar-cannula system, which reduces operating time. The first, or primary, cannula must be of sufficient caliber to permit passage of the laparoscope and usually is inserted in or at the lower border of the umbilicus. The incision should be extended only enough to allow insertion of the cannula; otherwise, leakage of gas may occur around the sheath. The patient should be in an unaltered supine position during placement of the primary cannula. For the primary puncture, either the surgeon or the assistant should elevate the abdominal wall as described previously. Both hands can be positioned on the device, using one to provide counter pressure and control to
Figure 23.7 Disposable access systems. These instruments are designed for single use. A 12-mm internal diameter blunt access system is shown in (A). The next device (B)hasa12mm internal diameter, but has a deployable blade that is used to cut through the abdominal wall. A smaller diameter blunt conical device is shown in (C) while a sharp conical access system is presented in (D). Both (C) and (D) have a 5-mm inside diameter. A narrow, 2.7-mm diameter cannula is shown in (E). The trocar for this system is a long insufﬂation needle with a spring deployable obturator.
prevent “overshoot” and resultant injury to bowel or vessels. The angle of insertion is the same as for the insufﬂation needle; adjustments are made according to the patient’s weight and body habitus (79). The laparoscope should be inserted to confirm proper intraperitoneal placement before the insufﬂation gas is allowed to ﬂow. Previous abdominal surgery increases the incidence of adhesions of the bowel to the anterior abdominal wall, frequently near the umbilicus and in the path of the primary trocar-cannula system (88,89). In such patients,
Figure 23.8 Reusable access systems. A: A sharp conical device, while (B) represents a pyramidal-tipped design. C and D (and inset): Images of the so-called EndoTip device that can be positioned in the abdominal wall by simply twisting or screwing it in without the requirement of a trocar.
another primary insertion site, such as the left upper quadrant, should be selected, even if it is used solely for conveying a narrow “scout” laparoscope, some types of which can be inserted through a trocar cannula system with a design similar to that of an insufﬂation needle (Fig. 23.9). Using such a laparoscope, the presence of adhesions under the incision can be identified and the umbilical cannula can be inserted under direct vision. If adhesions are noted under the incision, appropriate placement of secondary cannulas may be used to introduce instruments for adhesiolysis. Alternate insertion sites for primary cannulas are shown in Figure 23.6.
Figure 23.9 “Scout” laparoscope. The 2-mm laparoscope from Figure 23.8 and the 2.7-mm access system from Figure 23.7 are shown here assembled. The tubing is connected to inﬂow gas, usually carbon dioxide.