KEY POINTS
- Distances between the entry trocar and the aorta bifurcation increase directly with body mass index, mainly because of the commensurate increase in abdominal wall thickness.
- The mean thrusting force for insertion of a disposable trocar is 10.2 lb versus 17.53 lb for a reusable device, and the time to penetrate is shorter for the disposable trocar: mean of 3.54 seconds versus 11.64 seconds. Thus, greater caution is warranted when inserting a disposable trocar.
- Thrust the primary trocar into the midline of the abdomen at a 45° to 60° angle relative to the plane of the abdominal wall, with the trocar pointing toward the uterus, to avoid injuring the iliac vessels.
- When injury occurs, call for a vascular surgeon immediately, perform a laparotomy using a vertical incision, and get accurate inputs, outputs, and blood-loss estimates.
Major vessel injury is a two-sided coin: It can occur with alarming speed, but it is preventable.
Fortunately, the laparoscopic surgeon can avoid the problem by following simple precautions and steering clear of scenarios that increase the risk of injury. This article tells how to accomplish both objectives.
In the process, it reviews the evidence, details management for any injuries that occur, and includes a comprehensive table listing typical distances between the entry trocar and vascular structures, to help the surgeon adjust entry strategy.
Adequate prevention depends on:
- familiarity with the vascular anatomy, particularly in relation to the umbilicus, presacral space, infundibulopelvic ligament, and ovarian fossa.
- creating a proper pneumoperitoneum, especially when using disposable trocars.
- careful attention to primary trocar thrusting techniques to ensure midline insertion at the proper angle. Also exercise caution when placing secondary trocars. Specifically, during far lateral insertion, avoid cleaving the inferior epigastric artery from the external iliac or directly hitting the external artery or vein.
- avoiding long trocars, which are unnecessary to penetrate the peritoneal cavity.
- reliance on laparotomy if trocar insertion proves too difficult, vision is obscured, or appropriate anatomic dissection planes cannot be developed.
- when injury occurs, performing laparotomy using a vertical incision.
Insufflating the wrong space: A recipe for disaster
A 36-year-old woman with a body mass index of 38.2, indicating severe obesity, is scheduled to undergo hysteroscopy and dilatation and curettage for irregular bleeding, as well as laparoscopic bilateral partial salpingectomy for elective sterilization. The setting is an outpatient surgery center without a blood bank.
After general anesthesia, the surgeon makes a 1.5-cm incision just below the umbilicus, inserts a Verres needle, and insufflates carbon dioxide gas to a volume of approximately 3.4 L. He then inserts a disposable trocar and places a laparoscope, but views fat. Unbeknownst to him, he has insufflated the properitoneal fat space rather than the peritoneum.
The surgeon finally enters the peritoneum with a “long” trocar after several more attempts. Since the uterus and adnexa appear to be normal, he inserts a second trocar and places a probe. As he is moving the intestines, however, he observes blood, and the field suddenly becomes unclear. He removes the probe and, when the gas-pressure valve of the secondary trocar is opened, blood spews from the site.
The surgeon removes all trocars and performs an emergency laparotomy using a Pfannenstiel incision. He and 2 general surgeons, who arrive within 20 to 30 minutes, work for 2 hours to repair what they believe is a hole in the inferior vena cava. The woman is brought out of anesthesia and transferred to the local community hospital, where she goes into cardiac arrest and dies. A postmortem reveals injury to the right common iliac artery and vein. No sutures were observed in either vessel. Cause of death: exsanguination.
What went wrong?
Three serious errors contributed to the patient’s death:
- He made multiple attempts to insert the trocar without considering the possibility that the wrong space had been insufflated.
- He inserted the trocar off the midline and at the wrong angle relative to the abdominal wall.
- In his frustration, he switched to a “long” trocar, which made it more likely that vascular structures would be injured.
Operating on an obese patient in a center without a blood bank also was unwise, as obese women of short stature are at greatest risk for vascular injury.
How big is the problem?
A French study1 of 103,852 laparoscopic procedures—of which 15.7%, or 16,000 operations, were gynecologic—reported 47 cases of major vascular injury for an incidence of 0.5 per 1,000 cases and a mortality rate of 17%. Several additional articles2-8 reported a range of vascular complications of between 0.1 and 6.4 per 1,000 laparoscopies.