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Laparoscopic Entry Roundtable
Laparoscopic Entry Roundtable
Gary Frishman, MD, Moderator Associate Division Director of Reproductive Endocrinology and Residency Program Director at Women & Infants’ Hospital and Professor of Obstetrics of Gynecology at Warren Alpert Medical School of Brown University, Providence, Rhode Island William Hurd, MD, Participant Division Director, Reproductive Endocrinology at University Hospitals Case Medical Center and Professor of Reproductive Biology at Case Western Reserve University School of Medicine Richard Soderstrom, MD, Participant Professor Emeritus, University of Washington School of Medicine, Department of Obstetrics and Gynecology George Vilos, MD, Participant Professor, Department of Obstetrics and Gynecology, The University of Western Ontario, London, Canada Stephen Corson, MD, JMIG Editor Professor, Thomas Jefferson University, School of Medicine, Department Obstetrics and Gynecology, Philadelphia, Pennsylvania 37th AAGL Annual Meeting, The Paris Hotel, Las Vegas Nevada, Tuesday October 28, 2008 Dr. Frishman: Welcome and thank you for participating in this first JMIG-sponsored roundtable on minimally invasive gynecology. Our topic today is laparoscopic entry and technique. Our goal is to share our individual styles on the basis of our years of experience and our knowledge of the literature. Let’s start at the beginning. Should laparoscopy be considered a sterile procedure? Dr. Soderstrom: There has not been a large study for strict sterile technique for diagnostic or operative laparoscopy. Dr. Corson: Actually, we studied this question back in the days when the Association of Perioperative Registered Nurses insisted that scopes had to be gas sterilized and not soaked. As you can imagine, the inventory cost for a busy operating suite limited to 1 case per day per laparoscope was daunting. The results of our studies showed that soaking (in Cidex at that time) was sufficient for sterilization against all bacterial organisms except spore formers [1,2]. Peritoneal cultures demonstrated that the organisms present were driven in from the skin and not the instruments per se. 1553-4650/$ - see front matter doi:10.1016/j.jmig.2009.04.009
Dr. Frishman: It seems the risk of wound infection is very low in laparoscopy, and in many countries it has been traditional not to use a standard sterile technique nor wear a mask. Dr. Hurd: In the United States, sterile technique has become the standard, which becomes important if a procedure needs to be converted to laparotomy. Dr. Frishman: What are your thoughts on the height of the table in relation to the force and the ability to control the introduction of the Veress needle or trocar? Dr. Soderstrom: I teach the residents to adjust the height of the table to the comfort of the operator, because, if the table is too high, you may deviate laterally and increase the risk of vascular injury. Dr. Frishman: If the assistant surgeon is inserting the trocar or Veress needle, the table or step stools should be adjusted for the assistant. Dr. Frishman: What about the timing of placing the patient in the Trendelenburg position? Dr. Soderstrom: To decrease the risk of vascular injury, the patient should be flat during placement of the umbilical needle or trocar. Insert the telescope and inspect the omentum and bowel for possible injury before putting the patient into the Trendelenburg position. Dr. Hurd: Proper position is one of the most important factors for decreasing the risk of major vessel injury during trocar insertion. When the patient is in the Trendelenburg position, it is difficult to estimate the proper angle for trocar insertion. Dr. Frishman: What are people’s thoughts on direct trocar and other types of trocar insertion? Dr. Hurd: Trocar insertion after creation of pneumoperitoneum was the standard method used for years. Although direct trocar insertion has been adopted by many surgeons, large enough studies have not been performed to determine whether this approach is as safe as insertion after pneumoperitoneum. In fact, 1 study reported a significant risk of bowel injury even in the absence of adhesions, suggesting that the risk of bowel injury might actually be increased by direct trocar insertion [3]. The overall evidence does not support this. Direct insertion of the trocar is associated with less insufflation-related complications, and it is faster than the Veress needle technique [4]. Dr. Frishman: I am not aware of any individual studies adequately powered to address these questions. The Merlin meta-analysis did not show any meaningful differences from the perspective of significant complications [5].
Laparoscopic Entry Roundtable
Dr. Frishman: What do you recommend after the resident has made 2 to 3 unsuccessful passes with the Veress needle? The Royal College in the United Kingdom notes suggestions that, after 2 failed attempts to insert the Veress needle, an alternative such as Palmer’s point or open technique should be used [6]. Dr. Vilos: Three studies have shown that Veress insertion is successful 82% to 87% of the time after 1 attempt, 8% to 11% after 2 attempts, 2% to 4% after 3 attempts, and 0.7% to 3% after more than 3 attempts [7-9]. Dr. Soderstrom: If the attempts were made by doctors in training, I, as an instructor, would take over or switch to open laparoscopy. I am not aware of any data to prove whether that is the best thing to do outside of basic wisdom. Dr. Corson: The Richardson study correlated injury increases with the number of attempts made [7]. Dr. Hurd: Every laparoscopic surgeon should be comfortable using an alterative technique whenever multiple attempts using the closed technique have been unsuccessful. Two reasonable alternatives are Hasson’s open technique and the left upper quadrant approach with Palmer’s point. Dr. Soderstrom: I agree with Dr. Hurd regarding use of the upper left quadrant, and I believe this location works especially well with obese patients. I can not remember a single case where they could not insufflate with the left upper quadrant. I learned this from Dr. Jacques Rioux, who was taught by Dr. Raoul Palmer. The patient is first placed in the supine position, you place your hand on the left upper quadrant and pull down to make the skin taut, then about 3 cm from the midline and 2 cm below the costal margin, you insert the needle in cephalad. Dr. Frishman: Remember to place a nasogastric tube and that this is contraindicated if the patient has had surgery in the upper left quadrant. Dr. Corson: My understanding is that the original description was with use of 2 fingerbreadths from the midclavicular line and 15 degrees cephalad. Dr. Hurd: Currently, there are several recommendations for insertion angle at Palmer’s point, but there is no consensus. Dr. Soderstrom: I think we all agree that you should hear 2 pops rather than 3. Dr. Frishman: Is the left upper quadrant the technique of choice if you fail to obtain access via the umbilicus? Alternative sites include transfundal, cul-du-sac, and suprapubic; are there any cases to use these sites? Dr. Hurd: The left upper quadrant (LUQ) is a logical choice. Dr. Vilos: Yes, we use the LUQ after 3 failed attempts at the umbilicus and never failed entry at LUQ. Why not use this technique all the time because it is virtually failsafe? Dr. Soderstrom: The history of entry complications is interesting. A letter from August 23, 1996, was sent by the Food and Drug Administration (FDA) to the manufacturers of trocars, with the subject being shielded trocars and needles used for abdominal access during laparoscopy. The crux of the letter was the following sentence:
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Therefore the FDA is requesting in absence of clinical data showing reduced incidence of injury, manufacturers and distributors involuntary eliminate safety claims from labeling of shielded trocars and needles. The FDA does not object to labeling these devises as shielded trocars. Within 30 days of receipt of this letter please inform the office of compliance of your labeling indention. I don’t know if we have learned anything new since that letter [10]. Dr. Hurd: The injuries to retroperitoneal structures appear to be associated with the angle of insertion rather than the type of trocar used [11]. Dr. Corson: My colleague, Dr. Frances Batzer, and I measured the force needed to enter the abdomen (4-6 kg) with disposable and reusable trocars. We found that disposable trocars were generally sharper, required less force, and thus resulted in fewer injuries. The alloy for reusable trocars needed to be able to withstand repeated autoclaving and would become dull [12]. A similar study was done by Tarnay et al [13]. Dr. Frishman: I think we all agree that as long as the trocar is sharp, whether they are reusable or shielded does not matter. Dr. Hurd: Thousands of dollars have been spent on research, and no one has been able to reduce the risk of bowel and vessel injury with different types of trocars. In the early 1990s, with the introduction of disposable trocars, the number of complications actually increased [14]. Drs. Corson and Soderstrom have used the Ternamian device. This device uses the Archimedes screw principle to enter into the abdomen. Dr. Vilos: I am presenting at this AAGL annual meeting more than 4000 cases with this piece of equipment used with zero complications. The most reliable test for correct placement of the Veress needle is an initial peritoneal pressure of less than 10 mm Hg with evidence from 3 studies [8,9,15]. The Royal College of Obstetrics and Gynecology in England and our own [Canadian] guidelines indicate this conclusion [6]. In my own practice, I hook up the gas and have it flowing while observing the pressure as the needle goes through the abdominal wall. Once it penetrates the peritoneum, the pressure drops to less than 6 mm Hg in nearly all patients. In the slightly obese patients the pressure can be 7, 8 or 9, but essentially never greater than 10 mm Hg. This is true whether the Veress is inserted at the umbilicus or the LUQ because it is exactly the same. Dr. Hurd: Some people are concerned when the needle is hooked up to gas if you were to put it into a vessel, there is a possibility of more gas than you could safely insufflate getting into the venous system of the patient. Dr. Vilos: During that particular step, if a doctor is uncomfortable with the gas flowing, it is acceptable to first insert the Veress needle and then hook up the gas, or before they hook up the gas they could do an aspiration test to make sure it’s not in the vein. Dr. Frishman: Should the operator have the gas flow on low flow rate, not the high flow rate that many of these generators have for this step?
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Dr. Vilos: It does not matter what the insufflator is set at because flow is limited by the size of the Veress needle, and you would never get more than 3.0 L/min. Dr. Frishman: I believe that 1 L/min may be better during entry than 2 or 3. Dr. Hurd: If the needle is misplaced, preperitoneal insufflation can make the next insertion attempt more difficult. Dr. Vilos: I agree. However, if the needle is misplaced in the preperitoneal space, the initial pressure will rise very quickly to .10 mm Hg, warning the surgeon of its misplacement. I understand the objection people may have to the gas flow being on during the insertion. Dr. Soderstrom: What is the advantage, other than time, of having the gas flow on? Dr. Vilos: I like to see the pressure go up as the Veress traverses the abdominal wall and then down and know when I am in the abdominal cavity. Dr. Soderstrom: Would you know without the gas on? Dr. Vilos: Maybe, but this is how I started, and I am comfortable with this. Dr. Soderstrom: One of the things that I have taught my residents is to insert the needle hub with the valve closed and put a couple of drops of saline solution in the needle. Once you are in the subcutaneous fat or up against the fascia, open the valve, and as you drop into the abdominal cavity the saline solution will run through the needle. Dr. Vilos: Even if you are in the preperitoneal space, the saline solution will go right through the needle. Dr. Soderstrom: I understand, and this is to mainly show that you have gone through the tough tissue. Dr. Vilos: Two studies compared the various so-called Veress needle safety tests or checks including the saline drop test with the initial Veress pressure (the VIP-pressure). Both studies concluded that a VIP-pressure (,10 mm Hg) is the only reliable indicator for correct placement [9,15]. Dr. Vilos: How much CO2 is enough? It is an accepted fact that the pneumoperitoneum should be between 20 and 25 mm Hg, (although some doctors go to 30 mm Hg) before introducing the primary trocars. The British and Canadian guidelines agree on this. Although prolonged high intraabdominal pressure causes bradycardia, if you place your trocars within 2 minutes, there are no major changes to the cardiopulmonary system. We have measured the pulmonary compliance at pressures of 10, 15, 20, 25, and 30 mm Hg, and the compliance does decrease after 15 mm Hg by almost 30% to 40%. But the decrease is exactly the same as the compliance when the patient is in the Trendelenburg position at a pressure of 15 mm Hg, which is what we all use when we operate [16]. It is also recommended to insert the secondary trocars under high pressure and direct vision. I use Ternamian trocars, 10 mm at the umbilicus or LUQ and 5 mm laterally, with all of them inserted under direct vision. They are trocarless with no sharp components. I do not keep the pressure at 25 to 30 mm Hg but decrease it immediately after introduction of the primary cannula and insert the secondary trocars. For the last 2 years, I have used exclusively the Endo Tip
cannula. In our combined 4700 cases with Dr. Ternamian and Dr. Abu-Rafea from Saudi Arabia, using these 3 steps (insert Veress with flow on, high-pressure initial pneumoperitoneum, and Ternamian accessory trocar), we have not had a single entry complication [17]. Dr. Hurd: An advantage of not having the gas on when you insert the Veress is avoiding the rare incidence of intravascular insufflation and decreasing the less serious risk of preperitoneal insufflation. Dr. Corson: Dr. Vilos, why isn’t this device used by more people, and why isn’t it marketed more aggressively by Storz? Dr. Vilos: I am puzzled as well why Storz doesn’t market it more aggressively. I have talked to people at Storz, and I do not know their game plan. Dr. Soderstrom: I think it is because it is reusable and the company doesn’t make any money. Dr. Frishman: Let’s talk about the necessity of lifting the abdominal wall and different techniques like towel clips. I think we all agree that it is not possible to lift the abdominal wall away from the intraabdominal cavity without some insufflation. Dr. Soderstrom: I had a case that prompted me to do a study. An expert witness criticized a colleague for not lifting the abdomen when she impaled the vena cava before she inserted the trocar. The doctor inserted the needle, insufflated the abdominal cavity, then put the trocar in without lifting, which is the way I had taught her because her hands were small, and she wasn’t strong enough to lift the abdomen and had less control over the insertion of the trocar. So, during a laparoscopy after insufflation, I inserted a needle scope into the patient’s right flank. Under video control I had a 250pound resident try to lift abdominal fat and wall and demonstrated clearly that these efforts had no impact whatsoever on lifting the abdominal wall, and all it lifted was the fat. This was used as evidence in court, and they got a defense verdict. Dr. Hurd: It is important to remember that the goal is to minimize depression of the abdominal wall toward the vessels during Veress needle and trocar placement. Dr. Frishman: I think we are all in agreement that with direct trocar insertion everyone would lift the abdomen wall. Dr. Corson: Because there is no pressure in the abdomen, you can’t lift the wall off the organs. Dr. Hurd: But you may be able to lift the wall away from the major vessels. Dr. Vilos: Two studies, 1 with ultrasonography and the other with computed tomography (CT), determined the distance of the anterior peritoneum from the most adjacent bowel before lifting and after lifting. In the ultrasound study, the fascia was elevated with towel clips in 10 patients. The distance from the nearest bowel was 1.2 cm [18]. In the CT study, the fascia was elevated with sutures in 10 laparoscopic cholecystectomy patients. The distance from the nearest bowel was 1.9 cm [19]. In both studies, the space in between was taken up by omentum. Another study used a suprapubic port to compare the efficacy of manual lifting below the
Laparoscopic Entry Roundtable
umbilicus and of towel clips place within and 2 cm from the umbilicus. Only the towel clips provided significant elevation of peritoneum that was maintained during the force of the primary trocar insertion [20]. It must be pointed out, however, that the abdominal cavity had been breached and contained CO2. Dr. Soderstrom: I would suggest an observational exercise that I used to show my residents. When they are doing a laparotomy and have incised through the fascia and are observing the intact peritoneum, have them take 2 Kocher clamps and pull up on the fascia and view through the intact peritoneum for the bowel, which comes right up and is still contiguous with the peritoneum. Once you use a Veress needle, scissors, or scalpel to puncture that peritoneum, you hear the room air rushing in and see the bowel fall away. Dr. Frishman: Dr. Hurd, please comment on the angle of entry on the basis of the patient’s body mass index (BMI). Dr. Hurd: For heavier patients, the surgeon needs to use a near-vertical insertion angle to get through the abdominal wall. However, for thin patients the distance from the umbilicus to the vessels can be much smaller, and most vessel injuries happen in thin patients. For this reason we recommend that the angle of insertion should be 45 degrees from horizontal in patients with a BMI of ,30 kg/M [21]. Dr. Corson: I use the Z technique for thin patients, and it works particularly well. Dr. Frishman: Of note, the Z technique should only be used with the Veress needle and not the trocar; otherwise the tip of the trocar and, as such, the laparoscope is in the cul-du-sac. Dr. Soderstrom: If anyone is afraid of entry on an obese patient, use the left upper quadrant technique [22]. Dr. Vilos: I agree. The Consensus Document from Middleborough from 1999 recommends a perpendicular insertion of the Veress needle in all patients [23]. However, they do say at the same time the site of insertion should be stabilized by either lifting the umbilicus by hand or with a towel clip. I pull the lower abdominal wall below the umbilical caudally, essentially shifting the umbilicus away from the aortic bifurcation, and sacral promontory tethering the abdominal wall and inserting the Veress needle more perpendicularly in all patients. Dr. Hurd: That recommendation was made before anyone looked at the anatomy of the abdominal wall. Unfortunately, in patients who have a BMI of less than 25 kg/M2, the average distance from the umbilicus to the vessels is 2 to 4 cm [24]. There is no room for error in those patients who are at the highest risk for vessel injury. It makes sense to use a 45-degree angle on thin patients to avoid vessel injury. Dr. Vilos: I agree. Dr. Frishman: Dr. Hurd, do you use any particular maneuvers, such as towel clips, in the thin patient to minimize the risk of vessel injury? Dr. Hurd: I do not, but I have known surgeons who find this technique useful.
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Dr. Corson: I think that use of towel clips might cause more scarring. Dr. Frishman: Dr. Loffer taught this technique 30 years ago and thought it was very safe. I have used it with patients with a low BMI with no complications or problems. Dr. Frishman: Let’s go through a couple of points from the Royal College Guidelines. For our discussion, I will quote from this document. ‘‘In most circumstances the primary incision for laparoscopy should be vertical from the base of the umbilicus (not in the skin below the umbilicus). Care should be taken not to incise so deeply as to enter the peritoneal cavity’’ [6]. Dr. Soderstrom: That is according to the principle of Langer. Langer published an anatomic textbook at the turn of the century. The lines of Langer are associated with skin and are still the principle by which plastic surgeons do their work. By going against the Langer Principle, theoretically, you would get more scarring. Dr. Corson: When surgeons perform laparoscopic cholecystectomies, they go in the upper part of the umbilicus and point the needle upward. Do you think this is why they had more vascular injury? Dr. Soderstrom: Yes, agreed. Dr. Frishman: There are physicians who make a semicircular or half-moon incision below the umbilicus. I think going at the innermost base of the umbilicus is best both for cosmesis and because of the thin nature of the abdominal wall at that point. If you start from the most inner base of the umbilicus and incise caudally, you will be able to better control the total length of the incision and minimize how close it goes to the more visible inferior edge of the umbilicus. If you start from the inferior aspect of the outer edge of the umbilicus and then incise cranially, you are at greater risk of entering the abdomen with the scalpel in an uncontrolled manner if you slip, and your incision may be longer and less cosmetic because you don’t know how far out you have to start from the base of the umbilicus to achieve the necessary length for your trocar. Dr. Soderstrom: In 1973, the board of the AAGL got together to discuss how put the organization together. One thing they elected to do was teach each other their ‘‘tricks.’’ The first subject of the agenda was how and where to make the incision of the umbilicus. At that time people were using an elliptical incision because they were enthralled with the Pfannenstiel incision for abdominal hysterectomy and cesarean section. It wasn’t until a plastic surgeon pointed out they were going against the principles of Langer’s lines that they changed. Dr. Frishman: ‘‘Excessive lateral movement of the needle should be avoided, as this may convert a small needlepoint injury in the wall of the bowel or vessel into a more complex tear’’ [6]. I have read periodically about ‘‘waving’’ the Veress needle to make sure you are all the way through the abdominal wall. I feel strongly that this is not a good thing. Dr. Hurd: There has been a great deal of debate about this issue in Europe. Surgeons who support the use of the
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‘‘waggle test’’ say that an inability to move the Veress needle back and forth laterally indicates retroperitoneal placement and that it should be partially withdrawn before insufflation to avoid the rare but deadly complication of intravascular insufflation. Surgeons who oppose the use of the waggle test are concerned that it will enlarge any injury that has been made to vessel or bowel. I am not aware of any case where moving the needle laterally increased the size of an injury. Dr. Vilos: There was a case reported by Brosen [25] where an injury was increased from a 1.7-mm hole to an almost 1- to 2-cm hole. Dr. Frishman: Even though there are no data, if you look at the superficial omental vessels, they are large, unprotected, and fragile, and you can see where they might be easily damaged. Dr. Hurd: In my opinion, arguments for both sides of this controversy make some sense. However, because of the rarity of intravascular insufflation, it is unlikely that a study will ever be done to determine the best approach. Dr. Frishman: Does anyone want to comment on the size of the laparoscope and what you use routinely for standard laparoscopy? Dr. Hurd: It depends on the equipment available. With a state-of-the-art 3-chip camera and a good light cable, a 5-mm laparoscope has excellent optics. However, I have been in operating rooms that do not have the best equipment where a 5-mm laparoscope did not seem to have enough light. I think we all agree to use the best of what is available. Dr. Frishman: Does anyone use an angled laparoscope? All: No Dr. Hurd: Another advantage of using a 5-mm laparoscopic is that placement of a 5-mm trocar does not require as much force as a 10-mm trocar. Also, any bowel injury related to placement of the primary trocar is generally smaller and easier to repair. Finally, you can use the 5-mm laparoscope through ancillary ports for viewing the other trocar insertion sites if there is any concern. Dr. Frishman: Does anyone routinely look at their umbilical trocar site from below before they put the patient in the Trendelenburg position? Dr. Corson: You may have penetrated the bowel through and through and not realize it because you do not have a good view. Coming out you can look at as you withdraw the scope or move the scope to the inferior port to view the main trocar sheath. Dr. Hurd: I am familiar with a case where the primary port was placed completely through the small bowel adherent beneath the umbilicus, and this was not recognized by the surgeon until the patient returned with symptoms. In all cases, we inspect the abdomen with a complete 360-degree rotation of the laparoscope. Adhesions immediately behind the entry site become obvious with this technique. When an adhesion is found adjacent to the laparoscope port, you can inspect the insertion site through 1 of the other ports.
Dr. Frishman: Let’s talk about accessory trocars in terms of placement on the basis of anatomy and anticipated pathologic study. Dr. Hurd: We place our lower trocars more lateral and more cephalad than in the early days, using McBirnney’s point on the right and the equivalent point on the left to decrease the risk of hitting the inferior epigastric vessels, which are difficult to visualize in heavy patients. I try to avoid 10-mm trocars laterally unless it necessary because of the risk of Richter’s hernia and nerve damage. When needed, I place the 10- or 15-mm trocar in the midline whenever possible. Dr. Frishman: Please share with us the key anatomic landmarks. Dr. Hurd: It is important to attempt to laparoscopically visualize the epigastric vessels and upper margin of the bladder before trocar insertion in every patient. Unfortunately in the obese patients this is not always possible [26]. Dr. Frishman: How do you counsel the patient who is very interested in cosmesis about their incisions? You can bury the umbilical port, but what about the lateral ports? Dr. Hurd: For operative cases, cosmesis usually has to be a second. One helpful alternative is to use 5-mm instead of 8to 10-mm ports wherever possible. Dr. Soderstrom: I agree. Dr. Frishman: Would anyone would like to comment on the radially expanding trocars. I think that 1 positive is they are FDA approved with the claim that you do not have to close the fascia and have less risk of complications. Dr. Soderstrom: I do not have any experience with them. Dr. Vilos: Me neither. Dr. Hurd: It is possible that radially expanding trocars have not gained widespread acceptance because of cost. In Europe, conical tip trocars, as opposed to pyramidal tip trocars, are more commonly used in an attempt to minimize abdominal wall vessel injuries. The theory is that the tip moves vessels rather than transecting them. Dr. Frishman: Let’s talk about closing the fascia. Dr. Hurd, you have said that you don’t need to close the fascia if the trocar is 5 mm regardless of site. Dr. Vilos: The evidence shows that ports 10 mm or less do not have to be closed because it is not until you are above that size that hernias become more likely to occur. Dr. Frishman: It is important to note that significant manipulation of a smaller port, such as with suturing or specimen removal, will increase the size of the fascial defect. I personally always close a 10-mm regardless of location. Dr. Hurd: I do as well. Dr. Soderstrom: Historically, from the beginning of modern-day laparoscopy, only 10-mm laparoscopes were available, and the fascia was never closed. Dr. Frishman: This doesn’t mean people didn’t get hernias. Dr. Soderstrom: I taught use of the Z technique for insertion to decrease that risk [22]. Dr. Hurd: Although it remains controversial about whether you need to close a 10-mm umbilical site, most
Laparoscopic Entry Roundtable
people agree that you need to close lateral trocar sites that are 10 mm or larger. Dr. Frishman: Does anyone drop the pneumoperitoneum routinely or fill the pelvis with fluid at the end of the case to try to discern bleeding that might be hidden by the pressure associated with the pneumoperitoneum? Dr. Hurd: I close the large lateral ports under direct visualization with 1 of the various closure needles that are commercially available and observe the site of operation and trocar sites as I decrease the pneumoperitoneum to check for bleeding. Dr. Vilos: I remove all the trocars under direct vision, including the umbilical. I use an optical trocar so I can withdraw my laparoscope within the trocar sleeve seeing the layers closing behind me. The pressure is dropped before this technique with the camera in place, and I would be likely to see any significant vascular injury with this method. Dr. Frishman: What are people’s thoughts on preincisional and postincisional preemptive anesthesia? Do you use it and, if so, do you inject at the beginning or end and with what agent? Dr. Hurd: I have used Marcaine without epinephrine before making my incision except when doing an open laparoscopy because it makes the layers edematous. In these cases, I injection with Marcaine after the laparoscope has been successfully placed. I believe that it makes a significant difference in patient discomfort in the immediate postoperative period. Dr. Frishman: Why not with epinephrine? Dr. Corson: You don’t need epinephrine with marcaine. Dr. Hurd: My understanding is that epinephrine was used to slow vascular reabsorption with the shorter acting agents. Because Marcaine is relatively long acting, I have not used it with epinephrine. Dr. Frishman: There is a fair amount of literature on this, including meta-analysis, and it is far from clear [27]. My impression is that before is better than after and use of epinephrine makes sense. Certainly, I feel better doing it. Dr. Vilos: I use this routinely as well, although I think there may be data stating it does not decrease the requirement for postoperative analgesia. Dr. Corson: With these studies it is difficult to reach a consensus about whether it matters. Dr. Vilos: I agree. Dr. Frishman: Does anyone routinely use a nonsteroidal such as ketolorac? Dr. Vilos: I use it but not routinely. Dr. Frishman: Other than preincisional or postincisional anesthesia, is there anything you do, such as use smaller trocars, that you believe decreases postoperative pain? Dr. Vilos: I think it is important to address the issue of the removal of as much of the CO2 as possible. Dr. Hurd: This is particularly important when you use 5-mm trocars because the gas escapes more slowly, so you have to take your time. Dr. Corson: You should not push on the upper abdomen because it may push the bowel into the incision.
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Dr. Frishman: I instill 1 L or so of lactated Ringer’s solution to push the gas out. Dr. Vilos: I do this as well, using 0.5 to 1 L of Ringer’s lactate solution. Dr. Frishman: Also, this fluid improves your ability to see filmy adhesions and localize small bleeding vessels. Dr. Frishman: What do you prescribe for postoperative pain relief? I think we can agree that the pain should be diminishing each day, and the patient whose pain is not getting better needs to be seen. Dr. Vilos: I agree, and, if the pain is not better by the second postoperative day, something is going on. Dr. Frishman: Do you individualize your narcotics dose to the case, or is there a standard prescription you give to every patient? Dr. Vilos: For my patients, in the postoperative area they give intravenous narcotics, and when they go home I give a prescription for codeine with a nonsteroidal medication. Dr. Hurd: I routinely use hydrocodone rather than codeine because it seems to cause less nausea. Dr. Frishman: Does anyone have any experience with gasless laparoscopy, a technique that never became widespread? Dr. Vilos: I have no experience with this. Dr. Soderstrom: Me neither. Dr. Corson: This was popular in Asia. The Lap-O-Lift is popular with renal surgery and splenectomy. Dr. Frishman: Let’s turn to complications. How would you manage the transaction of an epigastric vessel? Dr. Hurd: Everyone should have a plan before they insert lateral trocars because occasionally abdominal wall vessel injuries will occur, often in the heaviest patients where you can’t see the vessels. My standard approach is first to try to stop the bleeding with bipolar electrosurgery placed through the opposite port. If I don’t have a side trocar in, I will put in a Foley catheter and lift it up to tamponade the vessel. Dr. Frishman: I will also try putting the bipolar through the trocar sleeve where the bleeding is, then pull the sleeve, leaving the bipolar device inside the abdominal wall up, permitting application of the bipolar within the incision. Dr. Hurd: If my first attempt does not work, I use the facial closure instruments to encircle the vessels below and above the trocar site. Dr. Corson: If you are using a fascial closure technique with a big needle to suture, you must remember the way the vessel runs and get perpendicular to it, tying the suture down over gauze so you don’t leave big suture marks. If you take a big bite, you should put some Marcaine in that incision because that will be very uncomfortable. Dr. Frishman: You can try to tie the suture in the incision line to drop the knot below the skin Dr. Hurd: I agree and attempt to leave the knot below the skin because of previous case reports of skin necrosis. Dr. Soderstrom: Dr. Corson and I wrote a paper long ago before the introduction of fascial closure devices to tie off the epigastric. You use a large curved needle and introduce it
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lateral to the vessel that is bleeding, starting out inside the trocar incision. With your laparoscope, observe the needle go through the peritoneum, go very deep below the vessel, and bring it back out through the abdominal wall. You then reverse directions and pass the needle back through that same exit hole, directing it now superficially and bringing it out again through the trocar incision, which allows you to tie the knot down inside the incision below the skin. This technique can be very difficult. Dr. Hurd: If you can not stop the bleeding from an injured epigastric vessel with any of these methods, I have made a small transverse incision through the skin and fascia and retracted the rectus muscle medially. The vessels, which lie immediately beneath the rectus muscle, can be clamped and tied without making a large incision. Dr. Frishman: To decrease the risk of bowel injury at the umbilical entry site, I have fallen in love with the visceral slide test. It is quick and easy to perform in the office or the preoperative area. For this, you place an abdominal ultrasound transducer over the umbilicus or your anticipated entry site and have the patient perform a big Valsalva maneuver, typically with a large breath. You then observe with ultrasonography the motion of the bowel underneath. The concept is if there is a significant sliding movement of the bowel with the Valsalva maneuver, then you know the bowel is not adherent directly underneath the probe. If the bowel wiggles in place without significant movement, it is possible there are adhesions in that region and then you can choose an alternate entry site. Dr. Ceana Nezhat took the visceral slide step a step further with his PUGSI test [28]. He reported on putting fluid in through a needle in the operating room with anesthesia, taking a large inspiration, and then observing the bowel’s movement; subsequently moving to other sites until a safe entry location is found as indicated. Dr. Frishman: Let’s talk about the risk of nerve damage resulting from a large lateral trocar site or manipulation of the lateral trocar. If a patient returns to the office with pain in that area, does anyone have a specific way they would handle this complaint? Dr. Hurd: I have also seen that kind pain after Pfannenstiel skin incisions. Treatment can be attempted with a local injection of Marcaine and steroid solution. Although few studies have evaluated the long-term effectiveness, this technique has long been used by pain specialists [29]. Dr. Corson: You need to make sure the patient doesn’t have a hernia. Dr. Frishman: Thank you all very much for your time and contributions. I would like to thank The Journal of Minimally Invasive Gynecology and Dr. Corson the editor for arranging this informative roundtable.
3. Kaali SG, Barad DH. Incidence of bowel injury due to dense adhesions at the sight of direct trocar insertion. J Reprod Med. 1992;37:617–618. 4. Vilos GA, Ternamian A, Dempster J, Laberge PY. The Society of Obstetricians and Gynaecologists of Canada. Laparoscopic entry: a review of techniques, technologies, and complications. J Obstet Gynaecol Can. 2007;29:433–465. 5. Merlin TL, Hiller JE, Maddern GJ, Jamieson GG, Brown AR, Kolbe A. Systematic review of the safety and effectiveness of methods used to establish pneumoperitoneum in laparoscopic surgery. Br J Surg. 2003; 90:668–679. 6. Gynaecologists RCoOa. Preventing entry-related gynaecological laparoscopic injuries. Green-top Guideline. May 2008;49. 7. Richardson R, Sutton CJG. Complications of first entry: a prospective laparoscopic audit. Gynecol Endosc. 1999;8:327–334. 8. Vilos GA, Vilos AG. Safe laparoscopic entry guided by Veress needle CO2 insufflation pressure. J Minim Invasive Gynecol. 2003;10:415–420. 9. Teoh BSR, Abbott J. An evaluation of four tests used to ascertain Veress needle placement at closed laparoscopy. J Minim Invasive Gynecol. 2005;12:153–158. 10. Yin LWC, Neidelman SM. Letter to manufacturers of laparoscopic trocars. FDA, Center for Devices and Radiological Health, Rockville MD. 1996, Aug 23. 11. Sharp HT, Dodson MK, Draper ML, Watts DA, Doucette RC, Hurd WW. Complications associated with optical-access laparoscopic trocars. Obstet Gynecol. Apr 2002;99:553–555. 12. Corson SL, Batzer FR, Gocial B, et al. Measurements of the force necessary for laparoscopic entry. J Reprod Med. 1994;34:282–284. 13. Tarnay CM, Glass KB, Munro MG. Entry force and intra-abdominal pressure associated with six laparoscopic trocar-cannula systems: a randomized comparison. Obstet Gynecol. 1999;94:83–88. 14. Deziel DJ. Complications of cholecystectomy. Incidence, clinical manifestations, and diagnosis. Surg Clin North Am. 1994;74:809–823. 15. Azevedo JLGR, Sorbella AA, et al. Evaluation of the positioning of the tip of the Veress needle during creation of closed pneumoperitoneum in pigs. Acta Cir Bras. 2006;21:385–391. 16. Abu-Rafea B, Vilos GA, Vilos AG, Ahmad R, Hollett-Caines J, Al-Omran M. High-pressure laparoscopic entry does not adversely affect cardiopulmonary function in healthy women. J Minim Invasive Gynecol. 2005;12:475–479. 17. Vilos GA, Ternamian AM, Vilos A, Abu-Rafea B, MacLeod NT, Tyrwhit J. Stepwise safe laparoscopic port establishment with trocarless cannulae under direct visual guidance. J Minim Invasive Gynecol. 2008; 15:s7. 18. Cakir TTD, Esmaeilzadem S, Atkan AO. Safe Veress needle insertion. J Hepatobiliary Pancreat Surg. 2006;13:225–227. 19. Shamiyeh AGK, Kratochwill H, et al. Lifting of the umbilicus for the installation of pneumoperitoneum with the Veress needle increased the distance to the retroperitoneal and intraperitoneal structures. Surg Endosc. 2009;23:313–317. 20. Roy GM, Bazzurini L, Solima E, Luciano AA. Safe technique for laparoscopic entry into the abdominal cavity. J Minim Invasive Gynecol. 2001;519–528. 21. Hurd WH, Bude RO, DeLancey JO, Gauvin JM, Aisen AM. Abdominal wall characterization with magnetic resonance imaging and computed tomography. The effect of obesity on the laparoscopic approach. J Reprod Med. 1991;36:473–476. 22. Soderstrom RM. Basic operative technique. In: Soderstrom RM, ed. Operative laparoscopy: the masters’ techniques. New York: Lippincott Raven Press. 1998:27-36. 23. Garry R. Towards evidence-based laparoscopic entry techniques: clinical problems and dilemmas. Gynaecological Endoscopy. 1999;8: 315–326. 24. Hurd WW, Bude RO, DeLancey JO, Pearl ML. The relationship of the umbilicus to the aortic bifurcation: implications for laparoscopic technique. Obstet Gynecol. 1992;80:48–51. 25. Brosen I, Gordon A. Bowel injuries during gynecological laparoscopy: a multinational surgery. Gynaecological Endosc. 2001;10:141–145.
References 1. Corson SL, Block S, Mintz C, Dole M, Wainwright A. Sterilization of laparoscopes. Is soaking sufficient? J Reprod Med. Aug 1979;23:49–56. 2. Corson SL, Dole M, Kraus R, Richards L, Logan B. Studies in sterilization of the laparoscope: II. J Reprod Med. Aug 1979;23:57–59.
Laparoscopic Entry Roundtable 26. Hurd WW, Amesse LS, Gruber JS, Horowitz GM, Cha GM, Hurteau JA. Visualization of the epigastric vessels and bladder before laparoscopic trocar placement. Fertil Steril. 2003;80:209–212. 27. Ong CK, Lirk P, Seymour RA, Jenkins BJ. The efficacy of preemptive analgesia for acute postoperative pain management: a meta-analysis. Anesth Analg. Mar 2005;100:757–773.
407 28. Nezhat C, Cho J, Morozov V, Yeung P Jr. Preoperative periumbilical ultrasound-guided saline infusion (PUGSI) as a tool in predicting obliterating subumbilical adhesions in laparoscopy. Fertil Steril. 2008 Jun 17. 29. Nazareno J, Ponich T, Gregor J. Long-term follow-up of trigger point injections for abdominal wall pain. Can J Gastroenterol. 2005;19: 561–565.
Gary Frishman, MD, Moderator Associate Division Director of Reproductive Endocrinology and Residency Program Director at Women & Infants’ Hospital and Professor of Obstetrics of Gynecology at Warren Alpert Medical School of Brown University, Providence, Rhode Island William Hurd, MD, Participant Division Director, Reproductive Endocrinology at University Hospitals Case Medical Center and Professor of Reproductive Biology at Case Western Reserve University School of Medicine Richard Soderstrom, MD, Participant Professor Emeritus, University of Washington School of Medicine, Department of Obstetrics and Gynecology George Vilos, MD, Participant Professor, Department of Obstetrics and Gynecology, The University of Western Ontario, London, Canada Stephen Corson, MD, JMIG Editor Professor, Thomas Jefferson University, School of Medicine, Department Obstetrics and Gynecology, Philadelphia, Pennsylvania 37th AAGL Annual Meeting, The Paris Hotel, Las Vegas Nevada, Tuesday October 28, 2008 Dr. Frishman: Welcome and thank you for participating in this first JMIG-sponsored roundtable on minimally invasive gynecology. Our topic today is laparoscopic entry and technique. Our goal is to share our individual styles on the basis of our years of experience and our knowledge of the literature. Let’s start at the beginning. Should laparoscopy be considered a sterile procedure? Dr. Soderstrom: There has not been a large study for strict sterile technique for diagnostic or operative laparoscopy. Dr. Corson: Actually, we studied this question back in the days when the Association of Perioperative Registered Nurses insisted that scopes had to be gas sterilized and not soaked. As you can imagine, the inventory cost for a busy operating suite limited to 1 case per day per laparoscope was daunting. The results of our studies showed that soaking (in Cidex at that time) was sufficient for sterilization against all bacterial organisms except spore formers [1,2]. Peritoneal cultures demonstrated that the organisms present were driven in from the skin and not the instruments per se. 1553-4650/$ - see front matter doi:10.1016/j.jmig.2009.04.009
Dr. Frishman: It seems the risk of wound infection is very low in laparoscopy, and in many countries it has been traditional not to use a standard sterile technique nor wear a mask. Dr. Hurd: In the United States, sterile technique has become the standard, which becomes important if a procedure needs to be converted to laparotomy. Dr. Frishman: What are your thoughts on the height of the table in relation to the force and the ability to control the introduction of the Veress needle or trocar? Dr. Soderstrom: I teach the residents to adjust the height of the table to the comfort of the operator, because, if the table is too high, you may deviate laterally and increase the risk of vascular injury. Dr. Frishman: If the assistant surgeon is inserting the trocar or Veress needle, the table or step stools should be adjusted for the assistant. Dr. Frishman: What about the timing of placing the patient in the Trendelenburg position? Dr. Soderstrom: To decrease the risk of vascular injury, the patient should be flat during placement of the umbilical needle or trocar. Insert the telescope and inspect the omentum and bowel for possible injury before putting the patient into the Trendelenburg position. Dr. Hurd: Proper position is one of the most important factors for decreasing the risk of major vessel injury during trocar insertion. When the patient is in the Trendelenburg position, it is difficult to estimate the proper angle for trocar insertion. Dr. Frishman: What are people’s thoughts on direct trocar and other types of trocar insertion? Dr. Hurd: Trocar insertion after creation of pneumoperitoneum was the standard method used for years. Although direct trocar insertion has been adopted by many surgeons, large enough studies have not been performed to determine whether this approach is as safe as insertion after pneumoperitoneum. In fact, 1 study reported a significant risk of bowel injury even in the absence of adhesions, suggesting that the risk of bowel injury might actually be increased by direct trocar insertion [3]. The overall evidence does not support this. Direct insertion of the trocar is associated with less insufflation-related complications, and it is faster than the Veress needle technique [4]. Dr. Frishman: I am not aware of any individual studies adequately powered to address these questions. The Merlin meta-analysis did not show any meaningful differences from the perspective of significant complications [5].
Laparoscopic Entry Roundtable
Dr. Frishman: What do you recommend after the resident has made 2 to 3 unsuccessful passes with the Veress needle? The Royal College in the United Kingdom notes suggestions that, after 2 failed attempts to insert the Veress needle, an alternative such as Palmer’s point or open technique should be used [6]. Dr. Vilos: Three studies have shown that Veress insertion is successful 82% to 87% of the time after 1 attempt, 8% to 11% after 2 attempts, 2% to 4% after 3 attempts, and 0.7% to 3% after more than 3 attempts [7-9]. Dr. Soderstrom: If the attempts were made by doctors in training, I, as an instructor, would take over or switch to open laparoscopy. I am not aware of any data to prove whether that is the best thing to do outside of basic wisdom. Dr. Corson: The Richardson study correlated injury increases with the number of attempts made [7]. Dr. Hurd: Every laparoscopic surgeon should be comfortable using an alterative technique whenever multiple attempts using the closed technique have been unsuccessful. Two reasonable alternatives are Hasson’s open technique and the left upper quadrant approach with Palmer’s point. Dr. Soderstrom: I agree with Dr. Hurd regarding use of the upper left quadrant, and I believe this location works especially well with obese patients. I can not remember a single case where they could not insufflate with the left upper quadrant. I learned this from Dr. Jacques Rioux, who was taught by Dr. Raoul Palmer. The patient is first placed in the supine position, you place your hand on the left upper quadrant and pull down to make the skin taut, then about 3 cm from the midline and 2 cm below the costal margin, you insert the needle in cephalad. Dr. Frishman: Remember to place a nasogastric tube and that this is contraindicated if the patient has had surgery in the upper left quadrant. Dr. Corson: My understanding is that the original description was with use of 2 fingerbreadths from the midclavicular line and 15 degrees cephalad. Dr. Hurd: Currently, there are several recommendations for insertion angle at Palmer’s point, but there is no consensus. Dr. Soderstrom: I think we all agree that you should hear 2 pops rather than 3. Dr. Frishman: Is the left upper quadrant the technique of choice if you fail to obtain access via the umbilicus? Alternative sites include transfundal, cul-du-sac, and suprapubic; are there any cases to use these sites? Dr. Hurd: The left upper quadrant (LUQ) is a logical choice. Dr. Vilos: Yes, we use the LUQ after 3 failed attempts at the umbilicus and never failed entry at LUQ. Why not use this technique all the time because it is virtually failsafe? Dr. Soderstrom: The history of entry complications is interesting. A letter from August 23, 1996, was sent by the Food and Drug Administration (FDA) to the manufacturers of trocars, with the subject being shielded trocars and needles used for abdominal access during laparoscopy. The crux of the letter was the following sentence:
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Therefore the FDA is requesting in absence of clinical data showing reduced incidence of injury, manufacturers and distributors involuntary eliminate safety claims from labeling of shielded trocars and needles. The FDA does not object to labeling these devises as shielded trocars. Within 30 days of receipt of this letter please inform the office of compliance of your labeling indention. I don’t know if we have learned anything new since that letter [10]. Dr. Hurd: The injuries to retroperitoneal structures appear to be associated with the angle of insertion rather than the type of trocar used [11]. Dr. Corson: My colleague, Dr. Frances Batzer, and I measured the force needed to enter the abdomen (4-6 kg) with disposable and reusable trocars. We found that disposable trocars were generally sharper, required less force, and thus resulted in fewer injuries. The alloy for reusable trocars needed to be able to withstand repeated autoclaving and would become dull [12]. A similar study was done by Tarnay et al [13]. Dr. Frishman: I think we all agree that as long as the trocar is sharp, whether they are reusable or shielded does not matter. Dr. Hurd: Thousands of dollars have been spent on research, and no one has been able to reduce the risk of bowel and vessel injury with different types of trocars. In the early 1990s, with the introduction of disposable trocars, the number of complications actually increased [14]. Drs. Corson and Soderstrom have used the Ternamian device. This device uses the Archimedes screw principle to enter into the abdomen. Dr. Vilos: I am presenting at this AAGL annual meeting more than 4000 cases with this piece of equipment used with zero complications. The most reliable test for correct placement of the Veress needle is an initial peritoneal pressure of less than 10 mm Hg with evidence from 3 studies [8,9,15]. The Royal College of Obstetrics and Gynecology in England and our own [Canadian] guidelines indicate this conclusion [6]. In my own practice, I hook up the gas and have it flowing while observing the pressure as the needle goes through the abdominal wall. Once it penetrates the peritoneum, the pressure drops to less than 6 mm Hg in nearly all patients. In the slightly obese patients the pressure can be 7, 8 or 9, but essentially never greater than 10 mm Hg. This is true whether the Veress is inserted at the umbilicus or the LUQ because it is exactly the same. Dr. Hurd: Some people are concerned when the needle is hooked up to gas if you were to put it into a vessel, there is a possibility of more gas than you could safely insufflate getting into the venous system of the patient. Dr. Vilos: During that particular step, if a doctor is uncomfortable with the gas flowing, it is acceptable to first insert the Veress needle and then hook up the gas, or before they hook up the gas they could do an aspiration test to make sure it’s not in the vein. Dr. Frishman: Should the operator have the gas flow on low flow rate, not the high flow rate that many of these generators have for this step?
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Dr. Vilos: It does not matter what the insufflator is set at because flow is limited by the size of the Veress needle, and you would never get more than 3.0 L/min. Dr. Frishman: I believe that 1 L/min may be better during entry than 2 or 3. Dr. Hurd: If the needle is misplaced, preperitoneal insufflation can make the next insertion attempt more difficult. Dr. Vilos: I agree. However, if the needle is misplaced in the preperitoneal space, the initial pressure will rise very quickly to .10 mm Hg, warning the surgeon of its misplacement. I understand the objection people may have to the gas flow being on during the insertion. Dr. Soderstrom: What is the advantage, other than time, of having the gas flow on? Dr. Vilos: I like to see the pressure go up as the Veress traverses the abdominal wall and then down and know when I am in the abdominal cavity. Dr. Soderstrom: Would you know without the gas on? Dr. Vilos: Maybe, but this is how I started, and I am comfortable with this. Dr. Soderstrom: One of the things that I have taught my residents is to insert the needle hub with the valve closed and put a couple of drops of saline solution in the needle. Once you are in the subcutaneous fat or up against the fascia, open the valve, and as you drop into the abdominal cavity the saline solution will run through the needle. Dr. Vilos: Even if you are in the preperitoneal space, the saline solution will go right through the needle. Dr. Soderstrom: I understand, and this is to mainly show that you have gone through the tough tissue. Dr. Vilos: Two studies compared the various so-called Veress needle safety tests or checks including the saline drop test with the initial Veress pressure (the VIP-pressure). Both studies concluded that a VIP-pressure (,10 mm Hg) is the only reliable indicator for correct placement [9,15]. Dr. Vilos: How much CO2 is enough? It is an accepted fact that the pneumoperitoneum should be between 20 and 25 mm Hg, (although some doctors go to 30 mm Hg) before introducing the primary trocars. The British and Canadian guidelines agree on this. Although prolonged high intraabdominal pressure causes bradycardia, if you place your trocars within 2 minutes, there are no major changes to the cardiopulmonary system. We have measured the pulmonary compliance at pressures of 10, 15, 20, 25, and 30 mm Hg, and the compliance does decrease after 15 mm Hg by almost 30% to 40%. But the decrease is exactly the same as the compliance when the patient is in the Trendelenburg position at a pressure of 15 mm Hg, which is what we all use when we operate [16]. It is also recommended to insert the secondary trocars under high pressure and direct vision. I use Ternamian trocars, 10 mm at the umbilicus or LUQ and 5 mm laterally, with all of them inserted under direct vision. They are trocarless with no sharp components. I do not keep the pressure at 25 to 30 mm Hg but decrease it immediately after introduction of the primary cannula and insert the secondary trocars. For the last 2 years, I have used exclusively the Endo Tip
cannula. In our combined 4700 cases with Dr. Ternamian and Dr. Abu-Rafea from Saudi Arabia, using these 3 steps (insert Veress with flow on, high-pressure initial pneumoperitoneum, and Ternamian accessory trocar), we have not had a single entry complication [17]. Dr. Hurd: An advantage of not having the gas on when you insert the Veress is avoiding the rare incidence of intravascular insufflation and decreasing the less serious risk of preperitoneal insufflation. Dr. Corson: Dr. Vilos, why isn’t this device used by more people, and why isn’t it marketed more aggressively by Storz? Dr. Vilos: I am puzzled as well why Storz doesn’t market it more aggressively. I have talked to people at Storz, and I do not know their game plan. Dr. Soderstrom: I think it is because it is reusable and the company doesn’t make any money. Dr. Frishman: Let’s talk about the necessity of lifting the abdominal wall and different techniques like towel clips. I think we all agree that it is not possible to lift the abdominal wall away from the intraabdominal cavity without some insufflation. Dr. Soderstrom: I had a case that prompted me to do a study. An expert witness criticized a colleague for not lifting the abdomen when she impaled the vena cava before she inserted the trocar. The doctor inserted the needle, insufflated the abdominal cavity, then put the trocar in without lifting, which is the way I had taught her because her hands were small, and she wasn’t strong enough to lift the abdomen and had less control over the insertion of the trocar. So, during a laparoscopy after insufflation, I inserted a needle scope into the patient’s right flank. Under video control I had a 250pound resident try to lift abdominal fat and wall and demonstrated clearly that these efforts had no impact whatsoever on lifting the abdominal wall, and all it lifted was the fat. This was used as evidence in court, and they got a defense verdict. Dr. Hurd: It is important to remember that the goal is to minimize depression of the abdominal wall toward the vessels during Veress needle and trocar placement. Dr. Frishman: I think we are all in agreement that with direct trocar insertion everyone would lift the abdomen wall. Dr. Corson: Because there is no pressure in the abdomen, you can’t lift the wall off the organs. Dr. Hurd: But you may be able to lift the wall away from the major vessels. Dr. Vilos: Two studies, 1 with ultrasonography and the other with computed tomography (CT), determined the distance of the anterior peritoneum from the most adjacent bowel before lifting and after lifting. In the ultrasound study, the fascia was elevated with towel clips in 10 patients. The distance from the nearest bowel was 1.2 cm [18]. In the CT study, the fascia was elevated with sutures in 10 laparoscopic cholecystectomy patients. The distance from the nearest bowel was 1.9 cm [19]. In both studies, the space in between was taken up by omentum. Another study used a suprapubic port to compare the efficacy of manual lifting below the
Laparoscopic Entry Roundtable
umbilicus and of towel clips place within and 2 cm from the umbilicus. Only the towel clips provided significant elevation of peritoneum that was maintained during the force of the primary trocar insertion [20]. It must be pointed out, however, that the abdominal cavity had been breached and contained CO2. Dr. Soderstrom: I would suggest an observational exercise that I used to show my residents. When they are doing a laparotomy and have incised through the fascia and are observing the intact peritoneum, have them take 2 Kocher clamps and pull up on the fascia and view through the intact peritoneum for the bowel, which comes right up and is still contiguous with the peritoneum. Once you use a Veress needle, scissors, or scalpel to puncture that peritoneum, you hear the room air rushing in and see the bowel fall away. Dr. Frishman: Dr. Hurd, please comment on the angle of entry on the basis of the patient’s body mass index (BMI). Dr. Hurd: For heavier patients, the surgeon needs to use a near-vertical insertion angle to get through the abdominal wall. However, for thin patients the distance from the umbilicus to the vessels can be much smaller, and most vessel injuries happen in thin patients. For this reason we recommend that the angle of insertion should be 45 degrees from horizontal in patients with a BMI of ,30 kg/M [21]. Dr. Corson: I use the Z technique for thin patients, and it works particularly well. Dr. Frishman: Of note, the Z technique should only be used with the Veress needle and not the trocar; otherwise the tip of the trocar and, as such, the laparoscope is in the cul-du-sac. Dr. Soderstrom: If anyone is afraid of entry on an obese patient, use the left upper quadrant technique [22]. Dr. Vilos: I agree. The Consensus Document from Middleborough from 1999 recommends a perpendicular insertion of the Veress needle in all patients [23]. However, they do say at the same time the site of insertion should be stabilized by either lifting the umbilicus by hand or with a towel clip. I pull the lower abdominal wall below the umbilical caudally, essentially shifting the umbilicus away from the aortic bifurcation, and sacral promontory tethering the abdominal wall and inserting the Veress needle more perpendicularly in all patients. Dr. Hurd: That recommendation was made before anyone looked at the anatomy of the abdominal wall. Unfortunately, in patients who have a BMI of less than 25 kg/M2, the average distance from the umbilicus to the vessels is 2 to 4 cm [24]. There is no room for error in those patients who are at the highest risk for vessel injury. It makes sense to use a 45-degree angle on thin patients to avoid vessel injury. Dr. Vilos: I agree. Dr. Frishman: Dr. Hurd, do you use any particular maneuvers, such as towel clips, in the thin patient to minimize the risk of vessel injury? Dr. Hurd: I do not, but I have known surgeons who find this technique useful.
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Dr. Corson: I think that use of towel clips might cause more scarring. Dr. Frishman: Dr. Loffer taught this technique 30 years ago and thought it was very safe. I have used it with patients with a low BMI with no complications or problems. Dr. Frishman: Let’s go through a couple of points from the Royal College Guidelines. For our discussion, I will quote from this document. ‘‘In most circumstances the primary incision for laparoscopy should be vertical from the base of the umbilicus (not in the skin below the umbilicus). Care should be taken not to incise so deeply as to enter the peritoneal cavity’’ [6]. Dr. Soderstrom: That is according to the principle of Langer. Langer published an anatomic textbook at the turn of the century. The lines of Langer are associated with skin and are still the principle by which plastic surgeons do their work. By going against the Langer Principle, theoretically, you would get more scarring. Dr. Corson: When surgeons perform laparoscopic cholecystectomies, they go in the upper part of the umbilicus and point the needle upward. Do you think this is why they had more vascular injury? Dr. Soderstrom: Yes, agreed. Dr. Frishman: There are physicians who make a semicircular or half-moon incision below the umbilicus. I think going at the innermost base of the umbilicus is best both for cosmesis and because of the thin nature of the abdominal wall at that point. If you start from the most inner base of the umbilicus and incise caudally, you will be able to better control the total length of the incision and minimize how close it goes to the more visible inferior edge of the umbilicus. If you start from the inferior aspect of the outer edge of the umbilicus and then incise cranially, you are at greater risk of entering the abdomen with the scalpel in an uncontrolled manner if you slip, and your incision may be longer and less cosmetic because you don’t know how far out you have to start from the base of the umbilicus to achieve the necessary length for your trocar. Dr. Soderstrom: In 1973, the board of the AAGL got together to discuss how put the organization together. One thing they elected to do was teach each other their ‘‘tricks.’’ The first subject of the agenda was how and where to make the incision of the umbilicus. At that time people were using an elliptical incision because they were enthralled with the Pfannenstiel incision for abdominal hysterectomy and cesarean section. It wasn’t until a plastic surgeon pointed out they were going against the principles of Langer’s lines that they changed. Dr. Frishman: ‘‘Excessive lateral movement of the needle should be avoided, as this may convert a small needlepoint injury in the wall of the bowel or vessel into a more complex tear’’ [6]. I have read periodically about ‘‘waving’’ the Veress needle to make sure you are all the way through the abdominal wall. I feel strongly that this is not a good thing. Dr. Hurd: There has been a great deal of debate about this issue in Europe. Surgeons who support the use of the
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‘‘waggle test’’ say that an inability to move the Veress needle back and forth laterally indicates retroperitoneal placement and that it should be partially withdrawn before insufflation to avoid the rare but deadly complication of intravascular insufflation. Surgeons who oppose the use of the waggle test are concerned that it will enlarge any injury that has been made to vessel or bowel. I am not aware of any case where moving the needle laterally increased the size of an injury. Dr. Vilos: There was a case reported by Brosen [25] where an injury was increased from a 1.7-mm hole to an almost 1- to 2-cm hole. Dr. Frishman: Even though there are no data, if you look at the superficial omental vessels, they are large, unprotected, and fragile, and you can see where they might be easily damaged. Dr. Hurd: In my opinion, arguments for both sides of this controversy make some sense. However, because of the rarity of intravascular insufflation, it is unlikely that a study will ever be done to determine the best approach. Dr. Frishman: Does anyone want to comment on the size of the laparoscope and what you use routinely for standard laparoscopy? Dr. Hurd: It depends on the equipment available. With a state-of-the-art 3-chip camera and a good light cable, a 5-mm laparoscope has excellent optics. However, I have been in operating rooms that do not have the best equipment where a 5-mm laparoscope did not seem to have enough light. I think we all agree to use the best of what is available. Dr. Frishman: Does anyone use an angled laparoscope? All: No Dr. Hurd: Another advantage of using a 5-mm laparoscopic is that placement of a 5-mm trocar does not require as much force as a 10-mm trocar. Also, any bowel injury related to placement of the primary trocar is generally smaller and easier to repair. Finally, you can use the 5-mm laparoscope through ancillary ports for viewing the other trocar insertion sites if there is any concern. Dr. Frishman: Does anyone routinely look at their umbilical trocar site from below before they put the patient in the Trendelenburg position? Dr. Corson: You may have penetrated the bowel through and through and not realize it because you do not have a good view. Coming out you can look at as you withdraw the scope or move the scope to the inferior port to view the main trocar sheath. Dr. Hurd: I am familiar with a case where the primary port was placed completely through the small bowel adherent beneath the umbilicus, and this was not recognized by the surgeon until the patient returned with symptoms. In all cases, we inspect the abdomen with a complete 360-degree rotation of the laparoscope. Adhesions immediately behind the entry site become obvious with this technique. When an adhesion is found adjacent to the laparoscope port, you can inspect the insertion site through 1 of the other ports.
Dr. Frishman: Let’s talk about accessory trocars in terms of placement on the basis of anatomy and anticipated pathologic study. Dr. Hurd: We place our lower trocars more lateral and more cephalad than in the early days, using McBirnney’s point on the right and the equivalent point on the left to decrease the risk of hitting the inferior epigastric vessels, which are difficult to visualize in heavy patients. I try to avoid 10-mm trocars laterally unless it necessary because of the risk of Richter’s hernia and nerve damage. When needed, I place the 10- or 15-mm trocar in the midline whenever possible. Dr. Frishman: Please share with us the key anatomic landmarks. Dr. Hurd: It is important to attempt to laparoscopically visualize the epigastric vessels and upper margin of the bladder before trocar insertion in every patient. Unfortunately in the obese patients this is not always possible [26]. Dr. Frishman: How do you counsel the patient who is very interested in cosmesis about their incisions? You can bury the umbilical port, but what about the lateral ports? Dr. Hurd: For operative cases, cosmesis usually has to be a second. One helpful alternative is to use 5-mm instead of 8to 10-mm ports wherever possible. Dr. Soderstrom: I agree. Dr. Frishman: Would anyone would like to comment on the radially expanding trocars. I think that 1 positive is they are FDA approved with the claim that you do not have to close the fascia and have less risk of complications. Dr. Soderstrom: I do not have any experience with them. Dr. Vilos: Me neither. Dr. Hurd: It is possible that radially expanding trocars have not gained widespread acceptance because of cost. In Europe, conical tip trocars, as opposed to pyramidal tip trocars, are more commonly used in an attempt to minimize abdominal wall vessel injuries. The theory is that the tip moves vessels rather than transecting them. Dr. Frishman: Let’s talk about closing the fascia. Dr. Hurd, you have said that you don’t need to close the fascia if the trocar is 5 mm regardless of site. Dr. Vilos: The evidence shows that ports 10 mm or less do not have to be closed because it is not until you are above that size that hernias become more likely to occur. Dr. Frishman: It is important to note that significant manipulation of a smaller port, such as with suturing or specimen removal, will increase the size of the fascial defect. I personally always close a 10-mm regardless of location. Dr. Hurd: I do as well. Dr. Soderstrom: Historically, from the beginning of modern-day laparoscopy, only 10-mm laparoscopes were available, and the fascia was never closed. Dr. Frishman: This doesn’t mean people didn’t get hernias. Dr. Soderstrom: I taught use of the Z technique for insertion to decrease that risk [22]. Dr. Hurd: Although it remains controversial about whether you need to close a 10-mm umbilical site, most
Laparoscopic Entry Roundtable
people agree that you need to close lateral trocar sites that are 10 mm or larger. Dr. Frishman: Does anyone drop the pneumoperitoneum routinely or fill the pelvis with fluid at the end of the case to try to discern bleeding that might be hidden by the pressure associated with the pneumoperitoneum? Dr. Hurd: I close the large lateral ports under direct visualization with 1 of the various closure needles that are commercially available and observe the site of operation and trocar sites as I decrease the pneumoperitoneum to check for bleeding. Dr. Vilos: I remove all the trocars under direct vision, including the umbilical. I use an optical trocar so I can withdraw my laparoscope within the trocar sleeve seeing the layers closing behind me. The pressure is dropped before this technique with the camera in place, and I would be likely to see any significant vascular injury with this method. Dr. Frishman: What are people’s thoughts on preincisional and postincisional preemptive anesthesia? Do you use it and, if so, do you inject at the beginning or end and with what agent? Dr. Hurd: I have used Marcaine without epinephrine before making my incision except when doing an open laparoscopy because it makes the layers edematous. In these cases, I injection with Marcaine after the laparoscope has been successfully placed. I believe that it makes a significant difference in patient discomfort in the immediate postoperative period. Dr. Frishman: Why not with epinephrine? Dr. Corson: You don’t need epinephrine with marcaine. Dr. Hurd: My understanding is that epinephrine was used to slow vascular reabsorption with the shorter acting agents. Because Marcaine is relatively long acting, I have not used it with epinephrine. Dr. Frishman: There is a fair amount of literature on this, including meta-analysis, and it is far from clear [27]. My impression is that before is better than after and use of epinephrine makes sense. Certainly, I feel better doing it. Dr. Vilos: I use this routinely as well, although I think there may be data stating it does not decrease the requirement for postoperative analgesia. Dr. Corson: With these studies it is difficult to reach a consensus about whether it matters. Dr. Vilos: I agree. Dr. Frishman: Does anyone routinely use a nonsteroidal such as ketolorac? Dr. Vilos: I use it but not routinely. Dr. Frishman: Other than preincisional or postincisional anesthesia, is there anything you do, such as use smaller trocars, that you believe decreases postoperative pain? Dr. Vilos: I think it is important to address the issue of the removal of as much of the CO2 as possible. Dr. Hurd: This is particularly important when you use 5-mm trocars because the gas escapes more slowly, so you have to take your time. Dr. Corson: You should not push on the upper abdomen because it may push the bowel into the incision.
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Dr. Frishman: I instill 1 L or so of lactated Ringer’s solution to push the gas out. Dr. Vilos: I do this as well, using 0.5 to 1 L of Ringer’s lactate solution. Dr. Frishman: Also, this fluid improves your ability to see filmy adhesions and localize small bleeding vessels. Dr. Frishman: What do you prescribe for postoperative pain relief? I think we can agree that the pain should be diminishing each day, and the patient whose pain is not getting better needs to be seen. Dr. Vilos: I agree, and, if the pain is not better by the second postoperative day, something is going on. Dr. Frishman: Do you individualize your narcotics dose to the case, or is there a standard prescription you give to every patient? Dr. Vilos: For my patients, in the postoperative area they give intravenous narcotics, and when they go home I give a prescription for codeine with a nonsteroidal medication. Dr. Hurd: I routinely use hydrocodone rather than codeine because it seems to cause less nausea. Dr. Frishman: Does anyone have any experience with gasless laparoscopy, a technique that never became widespread? Dr. Vilos: I have no experience with this. Dr. Soderstrom: Me neither. Dr. Corson: This was popular in Asia. The Lap-O-Lift is popular with renal surgery and splenectomy. Dr. Frishman: Let’s turn to complications. How would you manage the transaction of an epigastric vessel? Dr. Hurd: Everyone should have a plan before they insert lateral trocars because occasionally abdominal wall vessel injuries will occur, often in the heaviest patients where you can’t see the vessels. My standard approach is first to try to stop the bleeding with bipolar electrosurgery placed through the opposite port. If I don’t have a side trocar in, I will put in a Foley catheter and lift it up to tamponade the vessel. Dr. Frishman: I will also try putting the bipolar through the trocar sleeve where the bleeding is, then pull the sleeve, leaving the bipolar device inside the abdominal wall up, permitting application of the bipolar within the incision. Dr. Hurd: If my first attempt does not work, I use the facial closure instruments to encircle the vessels below and above the trocar site. Dr. Corson: If you are using a fascial closure technique with a big needle to suture, you must remember the way the vessel runs and get perpendicular to it, tying the suture down over gauze so you don’t leave big suture marks. If you take a big bite, you should put some Marcaine in that incision because that will be very uncomfortable. Dr. Frishman: You can try to tie the suture in the incision line to drop the knot below the skin Dr. Hurd: I agree and attempt to leave the knot below the skin because of previous case reports of skin necrosis. Dr. Soderstrom: Dr. Corson and I wrote a paper long ago before the introduction of fascial closure devices to tie off the epigastric. You use a large curved needle and introduce it
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lateral to the vessel that is bleeding, starting out inside the trocar incision. With your laparoscope, observe the needle go through the peritoneum, go very deep below the vessel, and bring it back out through the abdominal wall. You then reverse directions and pass the needle back through that same exit hole, directing it now superficially and bringing it out again through the trocar incision, which allows you to tie the knot down inside the incision below the skin. This technique can be very difficult. Dr. Hurd: If you can not stop the bleeding from an injured epigastric vessel with any of these methods, I have made a small transverse incision through the skin and fascia and retracted the rectus muscle medially. The vessels, which lie immediately beneath the rectus muscle, can be clamped and tied without making a large incision. Dr. Frishman: To decrease the risk of bowel injury at the umbilical entry site, I have fallen in love with the visceral slide test. It is quick and easy to perform in the office or the preoperative area. For this, you place an abdominal ultrasound transducer over the umbilicus or your anticipated entry site and have the patient perform a big Valsalva maneuver, typically with a large breath. You then observe with ultrasonography the motion of the bowel underneath. The concept is if there is a significant sliding movement of the bowel with the Valsalva maneuver, then you know the bowel is not adherent directly underneath the probe. If the bowel wiggles in place without significant movement, it is possible there are adhesions in that region and then you can choose an alternate entry site. Dr. Ceana Nezhat took the visceral slide step a step further with his PUGSI test [28]. He reported on putting fluid in through a needle in the operating room with anesthesia, taking a large inspiration, and then observing the bowel’s movement; subsequently moving to other sites until a safe entry location is found as indicated. Dr. Frishman: Let’s talk about the risk of nerve damage resulting from a large lateral trocar site or manipulation of the lateral trocar. If a patient returns to the office with pain in that area, does anyone have a specific way they would handle this complaint? Dr. Hurd: I have also seen that kind pain after Pfannenstiel skin incisions. Treatment can be attempted with a local injection of Marcaine and steroid solution. Although few studies have evaluated the long-term effectiveness, this technique has long been used by pain specialists [29]. Dr. Corson: You need to make sure the patient doesn’t have a hernia. Dr. Frishman: Thank you all very much for your time and contributions. I would like to thank The Journal of Minimally Invasive Gynecology and Dr. Corson the editor for arranging this informative roundtable.
3. Kaali SG, Barad DH. Incidence of bowel injury due to dense adhesions at the sight of direct trocar insertion. J Reprod Med. 1992;37:617–618. 4. Vilos GA, Ternamian A, Dempster J, Laberge PY. The Society of Obstetricians and Gynaecologists of Canada. Laparoscopic entry: a review of techniques, technologies, and complications. J Obstet Gynaecol Can. 2007;29:433–465. 5. Merlin TL, Hiller JE, Maddern GJ, Jamieson GG, Brown AR, Kolbe A. Systematic review of the safety and effectiveness of methods used to establish pneumoperitoneum in laparoscopic surgery. Br J Surg. 2003; 90:668–679. 6. Gynaecologists RCoOa. Preventing entry-related gynaecological laparoscopic injuries. Green-top Guideline. May 2008;49. 7. Richardson R, Sutton CJG. Complications of first entry: a prospective laparoscopic audit. Gynecol Endosc. 1999;8:327–334. 8. Vilos GA, Vilos AG. Safe laparoscopic entry guided by Veress needle CO2 insufflation pressure. J Minim Invasive Gynecol. 2003;10:415–420. 9. Teoh BSR, Abbott J. An evaluation of four tests used to ascertain Veress needle placement at closed laparoscopy. J Minim Invasive Gynecol. 2005;12:153–158. 10. Yin LWC, Neidelman SM. Letter to manufacturers of laparoscopic trocars. FDA, Center for Devices and Radiological Health, Rockville MD. 1996, Aug 23. 11. Sharp HT, Dodson MK, Draper ML, Watts DA, Doucette RC, Hurd WW. Complications associated with optical-access laparoscopic trocars. Obstet Gynecol. Apr 2002;99:553–555. 12. Corson SL, Batzer FR, Gocial B, et al. Measurements of the force necessary for laparoscopic entry. J Reprod Med. 1994;34:282–284. 13. Tarnay CM, Glass KB, Munro MG. Entry force and intra-abdominal pressure associated with six laparoscopic trocar-cannula systems: a randomized comparison. Obstet Gynecol. 1999;94:83–88. 14. Deziel DJ. Complications of cholecystectomy. Incidence, clinical manifestations, and diagnosis. Surg Clin North Am. 1994;74:809–823. 15. Azevedo JLGR, Sorbella AA, et al. Evaluation of the positioning of the tip of the Veress needle during creation of closed pneumoperitoneum in pigs. Acta Cir Bras. 2006;21:385–391. 16. Abu-Rafea B, Vilos GA, Vilos AG, Ahmad R, Hollett-Caines J, Al-Omran M. High-pressure laparoscopic entry does not adversely affect cardiopulmonary function in healthy women. J Minim Invasive Gynecol. 2005;12:475–479. 17. Vilos GA, Ternamian AM, Vilos A, Abu-Rafea B, MacLeod NT, Tyrwhit J. Stepwise safe laparoscopic port establishment with trocarless cannulae under direct visual guidance. J Minim Invasive Gynecol. 2008; 15:s7. 18. Cakir TTD, Esmaeilzadem S, Atkan AO. Safe Veress needle insertion. J Hepatobiliary Pancreat Surg. 2006;13:225–227. 19. Shamiyeh AGK, Kratochwill H, et al. Lifting of the umbilicus for the installation of pneumoperitoneum with the Veress needle increased the distance to the retroperitoneal and intraperitoneal structures. Surg Endosc. 2009;23:313–317. 20. Roy GM, Bazzurini L, Solima E, Luciano AA. Safe technique for laparoscopic entry into the abdominal cavity. J Minim Invasive Gynecol. 2001;519–528. 21. Hurd WH, Bude RO, DeLancey JO, Gauvin JM, Aisen AM. Abdominal wall characterization with magnetic resonance imaging and computed tomography. The effect of obesity on the laparoscopic approach. J Reprod Med. 1991;36:473–476. 22. Soderstrom RM. Basic operative technique. In: Soderstrom RM, ed. Operative laparoscopy: the masters’ techniques. New York: Lippincott Raven Press. 1998:27-36. 23. Garry R. Towards evidence-based laparoscopic entry techniques: clinical problems and dilemmas. Gynaecological Endoscopy. 1999;8: 315–326. 24. Hurd WW, Bude RO, DeLancey JO, Pearl ML. The relationship of the umbilicus to the aortic bifurcation: implications for laparoscopic technique. Obstet Gynecol. 1992;80:48–51. 25. Brosen I, Gordon A. Bowel injuries during gynecological laparoscopy: a multinational surgery. Gynaecological Endosc. 2001;10:141–145.
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407 28. Nezhat C, Cho J, Morozov V, Yeung P Jr. Preoperative periumbilical ultrasound-guided saline infusion (PUGSI) as a tool in predicting obliterating subumbilical adhesions in laparoscopy. Fertil Steril. 2008 Jun 17. 29. Nazareno J, Ponich T, Gregor J. Long-term follow-up of trigger point injections for abdominal wall pain. Can J Gastroenterol. 2005;19: 561–565.