The location of abdominal wall blood vessels in relationship to abdominal landmarks apparent at laparoscopy

Anatomical characteristics of the inferior epigastric artery in Uygur and it's implication in the management of bleeding

OBJECTIVES

This study aimed to determine the locations of the inferior epigastric arteries in a group of Uygur by ultrasound and explore the anatomical characteristics of vessels in the management of inferior epigastric bleeding.

METHODS

The study included 61 patients. The locations of inferior epigastric arteries through ultrasound were determined at three levels, and the distance from the midline was correlated with patients' demographics by Pearson correlation coefficient.

RESULTS

This study included 52 males and nine females, with a mean age of 37.56 years (± SD 3.16) and a mean BMI of 24.34 kg/m2 (± SD 3.71). At the symphysis pubis level, the average distance from the inferior epigastric artery to the midline was 5.98 ± 0.13 cm on the right and 7.32 ± 0.15 cm on the left. At the anterior superior iliac spine level, the average distance of the inferior epigastric artery on the right was 4.12 ± 0.15 cm and 5.2 ± 0.15 cm on the left. The inferior epigastric arteries were 3.86 ± 0.17 cm on the right and 5.06 ± 0.16 cm on the left of the midline at the level midway between the umbilicus and anterior superior iliac spine.

CONCLUSION

Inferior epigastric arteries were located between 3.5 and 8 cm from the midline, with the right vessel being closer to the midline than the left. The invasive operations through the abdominal wall should avoid these areas to reduce vascular injury. The anatomical characteristics of inferior epigastric arteries may potentially manage inferior epigastric bleeding.

Intraoperative complications during laparoscopic total mesorectal excision

Intraoperative complication during laparoscopic mesorectal excision for rectal cancer is a common complication occurring in 11% to 15% of the cases. They are probably underestimated because not systematically reported. The most frequent intraoperative complications are haemorrhage (3-7%), tumour perforation (1-4%), bowel injury (1-3%), ureter injury (1%), urogenital injury (2%), other organ injury (<1%), and anastomotic complications (1%). The mechanisms, management and prevention of vascular port injury, inferior mesenteric artery bleeding, small bowel and colon perforation, ureteral and urethral injury, pelvic nerve damage, tumour perforation and anastomotic failure are described. This review underlines the necessity to prevent intraoperative complication to avoid operative death and severe side-effects.

Guidelines on the management of ascites in cirrhosis

The British Society of Gastroenterology in collaboration with British Association for the Study of the Liver has prepared this document. The aim of this guideline is to review and summarise the evidence that guides clinical diagnosis and management of ascites in patients with cirrhosis. Substantial advances have been made in this area since the publication of the last guideline in 2007. These guidelines are based on a comprehensive literature search and comprise systematic reviews in the key areas, including the diagnostic tests, diuretic use, therapeutic paracentesis, use of albumin, transjugular intrahepatic portosystemic stent shunt, spontaneous bacterial peritonitis and beta-blockers in patients with ascites. Where recent systematic reviews and meta-analysis are available, these have been updated with additional studies. In addition, the results of prospective and retrospective studies, evidence obtained from expert committee reports and, in some instances, reports from case series have been included. Where possible, judgement has been made on the quality of information used to generate the guidelines and the specific recommendations have been made according to the 'Grading of Recommendations Assessment, Development and Evaluation (GRADE)' system. These guidelines are intended to inform practising clinicians, and it is expected that these guidelines will be revised in 3 years' time.

Development of a safety zone for rectus abdominis fascia graft harvest based on dissections of the ilioinguinal and iliohypogastric nerves

BACKGROUND

As a result of the vaginal mesh controversy, surgeons are performing more nonmesh, autologous fascia pubovaginal slings to treat stress urinary incontinence in women. The rectus abdominis fascia is the most commonly harvested site for autologous pubovaginal slings, so it is crucial that surgeons are familiar with the relationship between this graft harvest site and the ilioinguinal and iliohypogastric nerves, which can be injured during this procedure.

OBJECTIVE

The aims of this study were as follows: (1) to estimate the safest area between the bilateral courses of the ilioinguinal and iliohypogastric nerves in which a rectus abdominis fascia graft could be harvested with minimal risk of injury to these nerves and (2) to determine the location and dimensions of a graft harvest site that maximized graft length while remaining close to the pubic symphysis.

STUDY DESIGN

The ilioinguinal and iliohypogastric nerves were dissected bilaterally in 12 unembalmed female anatomical donors. The distances of these nerves to a 10 × 2 cm rectus abdominis fascia graft site located 4 cm above the pubic symphysis were measured. Nerve courses inferior to the graft site were determined for each donor by linearly extrapolating measurement points; analysis was performed with and without extrapolation. Average nerve trajectories were estimated assuming a linear regression function to predict the horizontal measurement as a quadratic function of the vertical distance; 95% confidence bands were also estimated. An estimated safety zone was determined to be the region between all credible nerve bounds.

RESULTS

The largest safety zone that was closest to the pubic symphysis was located at 5.4 cm superior to the pubic symphysis. At this location, the inferior border of the graft could measure 9.4 cm in length (4.7 cm bilaterally from the midline). Extrapolated nerve courses below the study graft site yielded a smaller safety zone located 2.7 cm superior to the pubic symphysis, allowing for the inferior border of the graft to be 4.8 cm (2.4 cm bilaterally from the midline).

CONCLUSION

A rectus abdominis fascia graft harvested 5.4 cm superior to the pubic symphysis with the inferior border of the graft measuring 9.4 cm in length should minimize injury to the ilioinguinal and iliohypogastric nerves. These dimensions allow for the longest graft while remaining relatively close to the pubic symphysis. The closer a graft is harvested to the pubic symphysis, the smaller in length the graft must be to avoid injury to the ilioinguinal and iliohypogastric nerves.

Ex vivo radiocontrast description of the caudal epigastric arteries in horses

OBJECTIVE

To determine the location of the deep and superficial caudal epigastric arteries in relation to 3 midline positions and the relationship between the location of these arteries, body circumference, and body condition score.

STUDY DESIGN

Descriptive anatomical study.

SAMPLE POPULATION

Nine horses, aged 1-28 years (mean 10.61 ± 8.89 SD).

METHODS

Body condition score and body circumference were measured prior to euthanasia. Angiographic studies of the deep and superficial caudal epigastric arteries were performed on resected abdominal walls. The distances between the deep and the superficial caudal epigastric arteries and 3 midline positions were measured. Correlations among these distances, body circumference, and body condition score were analyzed.

RESULTS

The location of the deep caudal epigastric artery correlated with body circumference and body condition score at the umbilicus (r = 0.53 and 0.68, respectively), midpoint landmark (r = 0.79 and 0.83, respectively), and prepubic tendon attachment (r = 0.69 and 0.78, respectively). The course of this artery could be estimated by multiplying body circumference by 0.04 ± 0.02 at the umbilicus, 0.07 ± 0.01 at the midpoint landmark, and 0.03 ± 0.015 at the prepubic tendon attachment. The course of the superficial caudal epigastric artery did not correlate with anatomic landmarks.

CONCLUSION

The course of the deep caudal epigastric artery could be estimated at 3 midline landmarks on the basis of body circumference and body condition score in equine cadavers.

CLINICAL SIGNIFICANCE

Predicting the course of the caudal epigastric arteries in the equine abdomen based on correlation among location, body circumference, and body condition score may prevent iatrogenic damage during creation of laparoscopic portals.

A Review of Laparoscopic Salpingo-Oophorectomy: Technique and Perioperative Considerations

Hysterectomy is the most frequently performed major gynecologic surgery in women in the United States. This procedure is often accompanied by unilateral or bilateral removal of the fallopian tubes and ovaries. Although the overall incidence of bilateral salpingo-oophorectomy has been shown to be in a decreasing trend in recent years, it is possibly 1 of the most common scenarios that the gynecologic surgeon will encounter. As the field of minimally invasive surgery continues to expand, it is expected that most of these surgeries will be performed using a laparoscopic approach. In fact, data support that adnexal surgery is more likely to take place during a laparoscopic hysterectomy when compared with abdominal or vaginal routes. This article reviews the basic surgical principles and relevant anatomic relations that every pelvic surgeon should know and aims to serve as a guide for effectively and proficiently performing a salpingo-oophorectomy at the time of hysterectomy.

Location of the Deep Epigastric Vessels in the Resting and Insufflated Abdomen

STUDY OBJECTIVE

To determine whether the location of the superior and inferior epigastric vessels (deep epigastric vessels) change with abdominal insufflation.

DESIGN

Descriptive study (Canadian Task Force classification III).

SETTING

Tertiary care academic institution.

PATIENTS

Patients undergoing gynecologic laparoscopic surgery were recruited. A total of 35 subjects were enrolled.

INTERVENTIONS

Subjects underwent color Doppler ultrasound assessment of deep epigastric vessel location preoperatively and intraoperatively following abdominal insufflation. The deep epigastric vessels were identified at 5 points along the abdomen (pubic symphysis, anterior superior iliac spine [ASIS], umbilicus, xiphoid, and midpoint from umbilicus to xiphoid), with the distance from vessels to midline measured. Paired t tests and split-plot analysis of variance were used as appropriate.

MEASUREMENTS AND MAIN RESULTS

The mean patient age was 45.6 ± 16.5 years, and mean BMI was 29.8 ± 7.2. A significant difference between vessel location in the resting abdomen and insufflated abdomen was noted bilaterally at the ASIS, umbilicus, and midpoint from the umbilicus to the xiphoid. At each of these points, the deep epigastric vessels were found more laterally after insufflation on average, ranging from 0.6 ± 0.9 cm (p < .001) more laterally at the midpoint between the umbilicus and xiphoid to 1.1 ± 0.8 cm (p < .001) more laterally at the umbilicus. The most lateral location of the deep vessels after insufflation was seen at the ASIS (10.6 cm) and the umbilicus (10.9 cm). In a subanalysis of subjects grouped by body mass index (obese vs nonobese), deep epigastric vessels were more lateral in the insufflated abdomen of obese subjects compared with that of nonobese subjects at the ASIS, umbilicus, and midpoint from umbilicus to xiphoid (p < .05 for each point bilaterally).

CONCLUSION

The deep epigastric vessels shift laterally with abdominal insufflation, and may be found as far as 10.9 cm from the midline; this is more lateral than previously described and is clinically significant. Obesity is associated with a more lateral location of the deep epigastric vessels.

Topography of inferior epigastric artery relevant to laparoscopy: a CT angiographic study

PURPOSE

The incidence of inferior epigastric artery (IEA) injury is 0.2-2 %. The aim of this study was to trace the position and course of the inferior epigastric artery in the anterior abdominal wall above the inguinal ligament at three important landmarks, i.e., at the mid-inguinal point, Anterior Superior Iliac Spine (ASIS) and umbilicus in abdominal CT Angiograms. The study also correlates the relationship of body build and the position of the inferior epigastric artery.

METHODS

In 50 CT Abdominal angiograms, the course of the inferior epigastric artery was traced and distance between the artery and midline was measured at the above landmarks using measurement tool on the picture archival and communication system. The measurements were analyzed using SPSS version 16 and expressed as mean and standard deviation. Mann-Whitney test was used to compare the mean values and ratios in males and females. Linear regression was done to derive formulas by which the position of the inferior epigastric artery could be found.

RESULTS

The mean distance of the inferior epigastric artery from the midline was 5.17 ± 0.93 cm at the level of mid-inguinal point, 4.57 ± 1.05 cm at the level of ASIS and 5.27 ± 1.17 cm at the level of umbilicus. There was a definitive predictive pattern in the course of the artery as seen in correlation and regression analysis.

CONCLUSION

The security distance for safe trocar placement was 6 cm at the level of ASIS and 9 cm at the level of umbilicus. Preoperative IEA assessment is helpful in reducing injuries to IEA.

Hemorrhagic shock after minor laparoscopic procedures

Severe bleeding from injury to abdominal wall blood vessels during minor laparoscopic procedures can occur. Two cases of shock presenting several hours after surgery are presented.

Recognition and management of major vessel injury during laparoscopy

Laparoscopy is one of the most commonly performed procedures in the United States. Injury to a major retroperitoneal vessel occurs in 0.3% to 1.0% of procedures, most commonly during laparoscopic entry while placing the Veress needle or primary trocar. Fatal outcome can be related to massive gas embolism or exsanguination. Recommended treatment for gas embolism can range from supportive measures to external chest compression and insertion of a central line to withdraw gas from the right side of the heart. Recommended treatment of major vessel injury with massive hemorrhage consists of rapid laparotomy and control of hemorrhage using direct pressure until a surgeon experienced in vascular procedures arrives. When a major vessel injury occurs in a surgical facility distant from a medical center and without an available surgeon with vascular experience, based on the trauma literature, we recommend temporary control of blood loss using abdominal packing and closure (i.e., "damage control surgery") and judicious resuscitation (i.e., "damage control resuscitation") before transportation to a medical center.

Hand-assist laparoscopic surgery for the gynecologic surgeon

Hand-assisted laparoscopic surgery (HALS) has not been extensively used in gynecologic surgery. This approach may offer a safe, viable alternative for gynecological cases that might otherwise require a large laparotomy incision.

Background:

Hand assist laparoscopy (HALS) is a minimally invasive technique which allows for the placement of the surgeon's non-dominant hand through a hand-port device while maintaining pneumoperitoneum. There is no standardization of this procedure and it is rarely used in gynecology.

Methods:

The multidisciplinary team of authors, with experience in minimally invasive pelvic surgery, has developed a practical approach performing HALS over several years. Here we present our technique.

Conclusions:

There are several roles for HALS in the world of gynecology and pelvic surgery. Further experience will help improve upon a standard technique.

Anterior abdominal wall nerve and vessel anatomy: clinical implications for gynecologic surgery

OBJECTIVE

We sought to describe relationships of clinically relevant nerves and vessels of the anterior abdominal wall.

STUDY DESIGN

The ilioinguinal and iliohypogastric nerves and inferior epigastric vessels were dissected in 11 unembalmed female cadavers. Distances from surface landmarks and common incision sites were recorded. Additional surface measurements were taken in 7 other specimens with and without insufflation.

RESULTS

The ilioinguinal nerve emerged through the internal oblique: mean (range), 2.5 (1.1-5.1) cm medial and 2.4 (0-5.3) cm inferior to the anterior superior iliac spine (ASIS). The iliohypogastric emerged 2.5 (0-4.6) cm medial and 2.0 (0-4.6) cm inferior. Inferior epigastric vessels were 3.7 (2.6-5.5) cm from midline at the level of the ASIS and always lateral to the rectus muscles at a level 2 cm superior to the pubic symphysis.

CONCLUSION

Risk of anterior abdominal wall nerve and vessel injury is minimized when lateral trocars are placed superior to the ASISs and >6 cm from midline and low transverse fascial incisions are not extended beyond the lateral borders of the rectus muscles.

The feasibility of scarless single-port transumbilical total laparoscopic hysterectomy: initial clinical experience

OBJECTIVE

The purpose of the present study is to demonstrate the feasibility of single-port transumbilical laparoscopic surgery (SPLS) for hysterectomy and elaborate on our experience in order to introduce the single-port approach for gynecologic surgery.

METHODS

Between August 2008 and February 2009, 30 patients who initially planned to undergo single-port laparoscopic surgery at Yonsei University Health System in Seoul, Korea were enrolled in this study. The authors used a single-port three-channel system with a wound retractor, surgical gloves, and one 10/11-mm and two 5-mm trocars. All surgical procedures were performed with 30 degrees , 5-mm laparoscope, conventional laparoscopic instruments, and the LigaSure system (Valleylab, Boulder, CO, USA). Patient characteristics and surgical outcomes were prospectively evaluated. A visual analog score (VAS) scale was used to measure postoperative pain.

RESULTS

Twenty-nine of 30 patients underwent single-port laparoscopic surgery without conversion to laparotomy or conventional laparoscopic hysterectomy. Median operative time was 100 min (57-155 min), median blood loss was 100 ml (10-400 ml), median postoperative hospital stay was 3 days (2-6 days), and median weight of resected uteri was 167 g (45-482 g). VAS scoring of pain at 6, 24, and 48 h after surgery was 4, 3, and 2, respectively. There were no operative complications.

CONCLUSION

SPLS is a feasible approach for hysterectomy in terms of operative time, complication rates, and cosmetic results. However, the possible benefits for patients such as better cosmetic outcomes, reduced pain, and lower complication rates should be evaluated in randomized prospective studies.

Prevention and treatment of abdominal wall bleeding complications at trocar sites: review of the literature

Abdominal wall bleeding may complicate any laparoscopic procedure. Piercing or laceration of vessels transversing the abdominal wall during trocar placement is generally the cause. Bleeding may occur at the very beginning of the surgery but, in some cases, it may go unrecognized for a while complicating the operation and the postoperative course. Planned and careful trocar placement can prevent most of these instances that otherwise can be readily managed avoiding severe morbidity.

Use of inferior epigastric artery embolization to arrest bleeding at operative laparoscopy

OBJECTIVE

To describe an innovative approach of embolization of the inferior epigastric artery after vascular trauma due to lateral trocar insertion at operative laparoscopy.

DESIGN

Case report.

SETTING

Operating theater and interventional radiology suite of a university hospital.

PATIENT(S)

A 26-year-old woman with polycystic ovaries refractory to clomiphene citrate undergoing laparoscopic ovarian drilling.

INTERVENTION(S)

Percutaneous selective left external iliac and left inferior epigastric angiography followed by embolization with platinum microcoils and polyvinyl alcohol.

MAIN OUTCOME MEASURE(S)

Satisfactory hemostasis following traumatic injury to the inferior epigastric artery.

RESULT(S)

Hemostasis was achieved using a novel interventive radiologic approach of embolization of the inferior epigastric artery after conventional surgical techniques had failed.

CONCLUSION(S)

Arterial embolization is a novel additional measure in the armamentarium of the laparoscopic surgeon faced with intractable bleeding from the inferior epigastric vessels.

Surface anatomy of the inferior epigastric artery in relation to laparoscopic injury

The inferior epigastric artery (IEA) is at risk of injury in laparoscopic surgery. Current descriptions of the course of the IEA do not provide surface landmarks useful to the surgeon. This study aimed to define surface relations and propose guidelines for safer trocar placement. The posterior surfaces of the anterior abdominal walls of 30 preserved cadavers were dissected. The surface anatomy of 60 IEAs and their branches were defined. At the level of the anterior superior iliac spine (ASIS), the IEA is 38% +/- 18% (95% confidence interval [CI]) from the midline to the ASIS. At the mid-inguinal point the relation is 40% +/- 17% and at the umbilicus 40% +/- 22%. The pattern of branches is highly variable. Although giving guidelines for trocar insertion can be treacherous, we found the following to be of value: 1) the midline is avascular; 2) the main stem of the IEA will be avoided if trocars are inserted more than two-thirds of the distance along a horizontal line between the midline and the ASIS; and 3) IEA branches are least frequently found in the lowest part of the abdomen lateral to the artery.

Visualization of the epigastric vessels and bladder before laparoscopic trocar placement

OBJECTIVE

Transillumination and laparoscopic visualization are two techniques recommended to minimize the risks of injury to abdominal wall structures during insertion of secondary trocars. This study was designed to determine the effectiveness of these techniques to locate the epigastric vessels and superior bladder margin.

DESIGN

Prospective observational.

SETTING

Academic medical centers.

PATIENT(S)

One hundred five women undergoing laparoscopy for tubal sterilization, infertility, pelvic masses, or pelvic pain.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The ability to visualize the superficial and inferior epigastric vessels, and bladder margin; body mass index (BMI; in kilograms per meter squared); and skin color.

RESULT(S)

Transillumination successfully visualized 64% of superficial epigastric vessels and was less effective both as weight increased (BMI <25 kg/m(2): 86%; BMI = 25-30 kg/m(2): 61%; BMI >30 kg/m(2): 25%) and in dark-skinned women (69%) compared to those with lighter skin (42%). Laparoscopic visualization successfully identified 82% of inferior epigastric vessels and 46% of bladder margins, and was less effective as weight increased.

CONCLUSION(S)

Transillumination can successfully locate superficial epigastric vessels, and laparoscopic visualization can locate inferior epigastric vessels and the superior bladder margin in the majority of women undergoing laparoscopy. Transillumination is less effective in dark-skinned women, and both techniques are less effective with increasing body weight.

A simple, inexpensive method of specimen removal at laparoscopy

After completing operative laparoscopy, it is often necessary to enlarge a 5-mm port to 10 or 12 mm for tissue removal. This may increase the risk of vessel injury and herniation, and has obvious cosmetic drawbacks. A simple, cost-effective technique for tissue removal does not require enlarging the 5-mm port. A long, firm thread is sutured to a sterile plastic bag. When tissue removal is required, the optic telescope is removed and the bag is blindly introduced through the available optical 11- or 12-mm cannula. The telescope is reintroduced, keeping the end of the thread outside the cannula sleeve. The specimen is placed in the bag and the bag is removed by pulling the suture through the optical cannula after removing the telescope. This technique was performed successfully in over 300 patients, with no difficulty or complication either during or after surgery. The device is inexpensive and takes 2 minutes to assemble.

Office laparoscopy under local anesthesia for gamete intrafallopian transfer: technique and tolerance

OBJECTIVE

To describe our technique for laparoscopic GIFT under local anesthesia and to evaluate patient tolerance and surgeon satisfaction in 175 consecutive procedures.

DESIGN

Prospective cohort study.

SETTING

University infertility practice.

PATIENT(S)

All GIFT candidates from 1992 to 1996 were offered the procedure. Of 119 patients, 119 chose local anesthesia for 175 procedures and 1 patient elected to have general anesthesia.

INTERVENTION(S)

Transvaginal ultrasound-guided egg retrieval followed by GIFT in the clinic procedure room with a 5-mm laparoscope and two accessory 3-mm trocars with local anesthesia and i.v. sedation.

MAIN OUTCOME MEASURE(S)

Patient tolerance and acceptance, duration of the procedure, amount of analgesics, surgeon satisfaction, and pregnancy rate (PR).

RESULT(S)

The laparoscopic portion lasted an average of 27 minutes, with a mean dose of 1.41 mg of midazolam and 68 micrograms of fentanyl used. Sixty-nine percent of the patients scored "very good," 20% "good," 9% "acceptable," and 2% "poor." All 38 patients undergoing 97 repeat procedures selected local anesthesia again. For women < 40 years of age, clinical PR and delivery rate were 43% and 38%, respectively.

CONCLUSION(S)

Routine office GIFT under local anesthesia is effective and well accepted by the surgeon and is preferred by patients. It offers a significant cost containment and scheduling flexibility in addition to high success rates.

Laparoscopic transillumination for the location of anterior abdominal wall blood vessels

OBJECTIVE

To determine the efficacy of transillumination for locating abdominal wall vessels prior to trocar placement during laparoscopy.

DESIGN

Prospective clinical descriptive study.

SETTING

Normal human volunteers in an academic research environment.

PATIENTS

Forty-seven white and 21 black women of various weights undergoing laparoscopy for clinical indications unrelated to this study.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

The location and number of abdominal wall vessels visible by transillumination were recorded for each patient.

RESULTS

In women of normal weight, a single vessel could be seen approximately 5 cm from the midline in > 90% of the patients, and second vessel approximately 8 cm from the midline could also be seen in 51%. The more medial vessels did not correlate with the course of the inferior epigastric vessels seen laparoscopically. The ability to see vessels was decreased significantly by the patients' weight but not by skin color.

CONCLUSIONS

Superficial abdominal wall vessels may be located by transillumination in the majority of women of normal weight regardless of skin color, but is of less value in overweight and obese women. However, the deep (inferior) epigastric vessels cannot be effectively located by transillumination, and thus other techniques should be used to minimize the risk of injury to these vessels.

Repair of laparoscopic injury to abdominal wall arteries complicated by cutaneous necrosis

Operative laparoscopic techniques requiring placement of large-bore cannulas through the abdominal wall lateral to the midline result in increased numbers of injuries to abdominal wall vessels. Five cases of inferior epigastric artery hemorrhage were controlled by percutaneous transabdominal placement of polypropylene sutures, allowing the procedure to be completed with the cannula in place. In two patients the sutures were left in place for 72 to 96 hours, and cutaneous necrosis occurred requiring debridement and delayed primary closure. In the other three women, removal of the sutures less than 24 hours postoperatively resulted in satisfactory hemostasis and primary healing of the abdominal wound. Percutaneous placement of polypropylene sutures may provide effective hemostasis after inferior epigastric artery hemorrhage due to cannula injury. Early suture removal may avoid potential cutaneous necrosis.

A comparison of the relative risk of vessel injury with conical versus pyramidal laparoscopic trocars in a rabbit model

OBJECTIVE

Our purpose was to compare the relative risk of vessel injury after use of a 5 mm conical-tipped trocar, a 5 mm pyramidal-tipped trocar, and a 10 mm pyramidal-tipped trocar in a rabbit vessel model.

STUDY DESIGN

Plastic templates were placed in front of and behind 108 mesenteric vessels in 11 anesthetized New Zealand White rabbits. Laparoscopic trocars were inserted through the templates and mesentery. The incidence of vessel injury was determined at distances from the vessels ranging from 0 to 5 mm.

RESULTS

The 5 mm conical trocar resulted in a vessel injury rate of 88% at 0 mm from the vessel but 0% at 1 or 2 mm. The 5 mm pyramidal trocar resulted in 100%, 88%, and 62% injury rates of 0, 1, and 2 mm from the vessels, respectively. The 10 mm pyramidal trocar resulted in a 100% injury rate at 0, 1, 2, or 3 mm from the vessels and 80% and 40% at 4 mm and 5mm, respectively.

CONCLUSION

The relative risk of vessel injury is significantly increased by the use of pyramidal-tipped trocars when compared with conical-tipped trocars, especially if larger diameter trocars are used.