Page 31 - Journal of WALS

Anaam Majeed Hasson
11
procedure. The frequency of entry complications reported in women. Insertion at 45°, even from within the umbilicus, means
the international literature is very low (1-3%). The most serious that the needle has to traverse distances of 11 to 16 cm, which
7
complications may be life-threatening, but are very rare with is too long for a standard Veress needle. Using MRI and CAT
the incidence of major vascular perforation reported as being scans (on unanesthetized women in the supine position) to
0.9 per 1000 procedures and the incidence of bowel perforation measure the thickness of the abdominal wall and critical
12
reported as being 1.8 per 1000 procedures. Even if the reported distances to the great vessels. Hurd et al reported that the
prevalence is very low, the mortality rate arising from these position of the umbilicus was found, on average, 0.4, 2.4 and 2.9
lesions reportedly ranges between 8 and 17%. 13 cm caudally to the aortic bifurcation in normal weight (BMI < 25
2
2
kg/m ), overweight (BMI 25-30 kg/m ) and obese (BMI >
2
Challenges with the Laparoscopic 30 kg/m ) women respectively (Fig. 1). In all cases, the umbilicus
Entry Techniques in Obese was cephalad toward the left common.
Although abdominal thickness correlates with patient weight, Iliac vein crossed the midline at the sacral promontory.
short stature or truncal obesity may increase abdominal wall Preperitoneal placement and vascular injury with a standard
thickness out of proportion to patient weight. Routine Veress needle (11.5 cm in length) is least likely using the
evaluation of the abdominal wall prior to laparoscopy is standard approach in nonobese women. In the overweight
important because the success of trocar insertion may depend patient, however, similar outcomes require modifying the point
on altering the technique based on abdominal wall thickness. 7 of needle insertion to the base of the umbilicus. Preperitoneal
Standard gynecologic laparoscopic entry is through the insufflation is least likely to occur in very obese women only if
umbilicus. Blindly passing a sharp Veress needle, insufflating, the needle is placed through the base of the umbilicus at a
and then blindly passing a sharp trocar is the traditional 90º angle. The fact that the umbilicus is usually caudal to the
technique for laparoscopic entry. Although it has been bifurcation in this weight group helps support the relative safety
suggested that the angle of Veress needle entry should vary of this modified approach. 14,15
between 45º and 90º according to the BMI of the patient, it is Moreover, the saline drop test should be used to confirm
reasonable to state that, for obese, a controlled 90º angle entry intraperitoneal Veress needle placement. Entry related
of the Veress needle with insertion of not more than 2 cm of the complications may be reduced by filling the peritoneal cavity
2
needle tip with selective umbilical stabilization or elevation of with carbon dioxide (CO ) to a predetermined pressure level
the abdominal wall is the safest route of Veress needle insertion rather than to a preset volume. Trocars may be placed angled
12
for the vast majority of cases. The angle of insertion is more towards the operation site to avoid torquing the instruments.
critical as the adipose layer limits free rotational movement of They can be sutured in place to prevent slippage and longer
working ports. Patients who are grossly obese are at a cannulas should be used. Finally, long instruments and extra
significantly greater risk of complications when undergoing ports along with routine bowel preparation will improve bowel
laparoscopic surgery. In most women, the aortic bifurcation manipulation, decrease bowel excursion into the operative field
16
rests between the 4th and 5th lumbar vertebrae, or within and ultimately better visualization.
1.25 cm above or below a line drawn between the iliac crests. Alternative methods of entry for insufflation may be required
Nevertheless, due to anatomic variation it may be located either when faced with the very obese patient or when conventional
above or below these disk spaces. The umbilicus is most methods are contraindicated or fail to produce an adequate
commonly located between the 3rd and 4th lumbar vertebrae. pneumoperitoneum. Accordingly, the initial entry can also be
However, this relationship is quite variable. The position of the performed through other sites in the abdominal wall, as 9th or
umbilicus relative to the aortic bifurcation is negatively 10th intercostal space or upper-left quadrant insertion site
correlated with body mass; it more commonly rests caudal to
14
the bifurcation in overweight and very obese women. If a
Veress needle approach is used in the patient who is morbidly
obese, an ultralong Veress needle may assist, also it is important
to make the vertical incision as deep as possible in the base of
the umbilicus, since this is the area where skin, deep fascia and
parietal peritoneum of the anterior abdominal wall will meet. In
this area, there is little opportunity for the parietal peritoneum
to tent away from the Veress needle and allow preperitoneal
insufflation and surgical emphysema. If the needle is inserted
vertically, the mean distance from the lower margin of the
umbilicus to the peritoneum is 6 cm (± 3 cm). This allows
placement of a standard length needle even in extremely obese Fig.1: Effect of obesity on location of great vessels

98
JAYPEE