Single-Port Surgery

Abstract

Conventional laparoscopy is the preferred approach for many, if not most, major gynecologic procedures that require abdominal access. Conventional laparoscopic instrumentation and access devices as well as robotic-assisted laparoscopic instrumentation are improving rapidly. Whether conventional or robotic laparoscopy is considered, we prefer to minimize the size and number of ports. Many surgical procedures are customarily performed via 3–5 ports through small incisions in the abdominal wall. Each additional port carries a small but not negligible risk for port site complications [1]. These risks include bleeding, infection, injury to nearby organs, soft tissue trauma, herniation, and decreased cosmesis [2, 3].

Introduction

Conventional laparoscopy is the preferred approach for many, if not most, major gynecologic procedures that require abdominal access. Conventional laparoscopic instrumentation and access devices as well as robotic-assisted laparoscopic instrumentation are improving rapidly. Whether conventional or robotic laparoscopy is considered, we prefer to minimize the size and number of ports. Many surgical procedures are customarily performed via 3–5 ports through small incisions in the abdominal wall. Each additional port carries a small but not negligible risk for port site complications [1]. These risks include bleeding, infection, injury to nearby organs, soft tissue trauma, herniation, and decreased cosmesis [2, 3].

Single-port laparoscopy was first described in gynecology when Wheeless et al. performed tubal ligation [4]. The first major single-port laparoscopy was described by Pelosi et al. with laparoscopic-assisted vaginal hysterectomy [5]. With new instrumentation and better visualization, gynecologists began re-exploring single-port laparoscopy again in 2007.

To this day, authors around the world use multiple terms to describe laparoscopy carried out via a single port. However, in 2010, a multispecialty international consortium recommended the name laparo-endoscopic single-site surgery (LESS) [6]. LESS is meant to recognize and include subtle differences in technique such as using a single port with or without multiple channels or using multiple ports through a single skin incision.

A consortium of LESS experts developed a standardized and reproducible technique using Core Principles to perform LESS surgery in gynecology (Table 4.1) [7]. This chapter will cover the basic concepts that are easily understood, replicated, and useful for beginning and advanced LESS surgeons. Challenges unique to the LESS surgical approach include an in-line view, instrument crowding, and lack of triangulation. Understanding the principles and techniques described here will help the surgeon proceed efficiently, avoid external and internal clashing, and prevent frustration.

Table 4.1 Core principles for LESS

Ports and Gaining Access

One of the benefits of LESS is the incision is concealed at the base of the umbilicus, rendering a virtually scarless result. Various access devices and techniques have been described for peritoneal access. Regardless of the method used, the skin incision should be created to provide a cosmetically appealing result. The umbilicus itself is a scar that differs from person to person. In many patients, a vertical skin incision is preferable. However, the omega incision first described by pediatric surgeons in 1986 can provide additional space for specimen removal while maintaining excellent cosmesis [8, 9] (Fig. 4.1). It has been postulated by some that an omega umbilical incision may carry an increased risk of infection. However, a retrospective study in gynecology compared vertical and circumferential umbilical incisions in 120 patients that underwent a LESS procedure and did not find a difference in rates of infection [10]. Special care should be taken to ensure careful reconstruction of the umbilicus for the best cosmetic result. If the umbilical stalk is detached from the fascia, it should be reattached to the fascia where it was previously attached [11]. Limiting the size of the incision may exert unnecessary tension on the skin edges that could lead to pressure necrosis. Although this condition usually heals well, this risk should be considered while making the skin incision and selecting the appropriate port for each patient.

Fig. 4.1

Incision options. Top, vertical skin incision before (left) and after (right). Bottom, omega incision before (left) and after (right)

The majority of commercially available LESS ports have two attachments that can be used for insufflation, outflow, smoke evacuation, or an additional insufflation port as necessary (Fig. 4.2). There are several patented port systems currently cleared by the US Food and Drug Administration for LESS, which will be discussed next.

Fig. 4.2

LESS ports. (a) The X-CONE™ (Storz Endoscopy, Tuttlingen, Germany). (b) AnchorPort® SIL Kit device (Surgiquest Inc., Orange, CT). (c) SILS™ Port (Covidien, Norwalk, CT). (d) GelPoint™ (Applied Medical, Rancho Santa Margarita, CA). (e) TriPort Plus™ (Advanced Surgical Concepts, Wicklow, Ireland). (f) TriPort 15™ (Advanced Surgical Concepts, Wicklow, Ireland)

The AirSeal port (SurgiQuest, Inc., Orange, Connecticut, USA) creates pneumoperitoneum by creating an air seal, which results from flow of air around the port at a higher pressure that what the pneumoperitoneum creates. One of the biggest advantages of this system is that the constant air circulation reduces smoke accumulation [12].

The GelPoint system (Applied Medical Resources Corp., Rancho Santa Margarita, California, USA) is comprised of a wound retractor that is placed in the incision. Next, a 10 cm gel cap is placed over the outer ring of the retractor. This cap is made of a gel interface that allows the surgeon to pass many instruments through this interface with the provided cannulas and decrease instrument crowding. The biggest disadvantage of this system is the potential for a gas leak if the gel interface has a large slit [12].

Covidien (Mansfield, Massachusetts, USA) developed a system called the SILS Port. It can accommodate up to three instruments through a single fascial incision up to 2 cm in length. The port is made of an elastic polymer. An advantage of this system is that each instrument has it’s own dedicated channel. Ports with dedicated channels provide less rubbing or unintended crossing of the instruments at the level of the fascia. A disadvantage is that the port requires a slightly larger incision 2.0–2.5 cm). Ports that utilize a single fascial incision maximize space for additional instruments.

TriPort by Advanced Surgical Concepts, Ltd., (Bray, County Wicklow, Ireland) comes in two configurations. Each has a retraction sleeve with two or three 5 mm ports and one 12 mm or 15 mm port. This system is very advantageous because it can be used on varying abdominal wall lengths, up to 10 cm. If the retraction sleeve is damaged, loss of pneumoperitoneum may result [12].

Karl Storz GmbH & Co. KG (Tuttlingen, Germany) developed the X-CONE and ENDOCONE; however, it is not currently approved by the US FDA for use in the United States.

Surgeons also successfully use noncommercial ports constructed from retractors, gloves, and other materials readily available in any operating room [13].

When necessary, conversion to two-port or multiport conventional laparoscopy should not be considered a complication.

Set Up and Instrumentation

The majority of gynecologic LESS surgical procedures can be performed using conventional straight instrumentation available in all operating rooms. Some surgeons use specialized articulating and curved instruments specifically designed for LESS surgery to help overcome the lack of triangulation. However, there is generally a learning curve associated with these devices.

An articulating camera has some significant advantages over conventional laparoscopes in LESS surgery and is preferred by most experts. However, bariatric length or longer, 30° or 45° laparoscopes can also be used in LESS surgery with the techniques and principles described here. Conventional laparoscopes have a light cable perpendicular to the scope, which can exacerbate external crowding and clashing, an obstacle already inherit to LESS procedures. In contrast, articulating cameras are designed with a single cord, which includes the light source in the same axis as the scope to help minimize external crowding (Fig. 4.3b). If a non-articulating laparoscope is used, we recommend using a 90° adaptor to minimize interference from the light cord (Fig. 4.3a and inset).

Fig. 4.3

Laparoscope options. (a) 30° or 45° laparoscope for LESS with 90° light cord adaptor (inset). (b) Articulating laparoscope (EndoEye™ (Olympus Surgical & Industrial America Inc., Center Valley, PA))

During LESS procedures, uterine manipulation is essential. A uterine manipulator can provide another means to retract the uterus. Common manipulators include systems such as the RUMI with KOH Colpotomizer (CooperSurgical, Trumbull, Connecticut, USA) and the VCare uterine manipulator (ConMed Corporation, Utica, New York USA). Both of these systems come with different sizes of colpotomy cups in order to help displace the ureters laterally and delineate the cervicovaginal junction [14].

Candidate Selection

There is no set criterion that defines the ideal patient for a LESS procedure. Fader and Escobar [15] studied outcomes and found no differences in groups stratified based on BMI, comorbidities, or previous surgeries. It has been suggested, however, that patients with a BMI greater than 28 kg/m² may pose a surgical challenge due to thicker abdominal walls or large amount of intraperitoneal fat [16]. Additionally, patients who’ve had prior surgeries may represent a challenge due to pelvic adhesions. Therefore, Chern et al. suggest that patients who are not ideal candidates for this procedure include those with high BMI, greater than two prior laparotomies, malignancy, or who do not have a native umbilicus [16]. Although the techniques described here work well for complex surgical cases, we strongly recommend surgeons first become familiar with the technique for simple procedures with benign indications. As with any surgical approach, complicating factors, such as endometriosis, large fibroid uteri, malignancy, and significant adhesions, represent an additional layer of complexity and are not addressed here. We recommended those cases be reserved for experienced LESS surgeons.

Key Steps

There are a few key steps and principles for an efficient LESS procedure. We present a simplified and efficient technique that is useful in all gynecologic procedures. This technique when strictly followed will eliminate extraneous or duplicative movements. Together with the Core Principles in Table 4.1, this technique will maximize space between instruments and avoid extracorporeal and intracorporeal clashing and crossing. The instructions that follow assume the primary surgeon is on the patient’s left side. This process could be reversed if the surgeon is standing on the opposite side.

Step 1: Orientation of the Port and Camera Placement

The surgeon should choose the port so that the advantages and disadvantages of the specific port are well suited to the complexity of the case. Once securely placed in the peritoneal cavity, the port should be oriented as in Fig. 4.4. The channels or valves should be oriented so that the laparoscope can be placed through the most cephalad channel. This allows the camera to be lowered externally toward the chest wall while elevating the internal end of the laparoscope toward the anterior abdominal wall. Then, use the articulation or angle of the scope to position the camera low and laterally (Fig. 4.5). Externally, this positions the assistant’s hand and the external aspect of the camera away from the umbilicus to allow space for other instruments and permit the primary surgeon to operate directly above the umbilical port without external clashing. The greater the angle of the laparoscope (30°, 45°, or flexible), the easier it is to get the camera away from the operative field and avoid clashing.

Fig. 4.4

Port orientation and camera placement. The laparoscope is placed through the cephalad channel, valve, or cannula

Fig. 4.5

Camera placement. The camera should be placed first prior to any additional instruments. Use the articulation or angle of the scope to position the camera and light cord low and lateral

Step 2: Insert the Assistant Instrument

According to the Core Principles, all retraction by any assistant grasper should be performed by lateral retraction of the handle away from midline. Always retract in such a way that the handle of the instrument moves laterally, away from the camera and central area above the umbilicus. This means that the tissue is actually being retracted across the pelvis toward the contralateral side. This maximizes room for the laparoscope and other instruments externally preventing extracorporeal clashing of instruments. For example, to retract a uterus to the right, an assistant grasper instrument is inserted through the left port channel and controlled by moving the handle laterally to deviate the uterus to the right (Fig. 4.6). If the instrument was inadvertently inserted through the right port channel and then the uterus is retracted toward the right (internally), the instrument handle would move toward the central area above the umbilicus—thus limiting space externally and causing clashing. Therefore, it is very important to place the assistant instrument through the port on the side in the direction of the lateral retraction so that the port channel and instrument move laterally, away from midline.

Fig. 4.6

(a and b) Insertion of the assistant grasper. Always retract so that the handle moves laterally, away from the midline

Step 3: Insert the Operating Electrosurgical Instrument

The operating instrument will be inserted through the right channel (Fig. 4.7). It will enter the internal operative field through the center and usually be directed straight toward the surgical target. In the event that the instrument handles interfere with each other or the camera, the handles should be positioned opposite of each other (Fig. 4.7).

Fig. 4.7

External instrument position. External view showing setup and instrument positions without clashing. Note handles of the bipolar device and assistant grasper are facing opposite directions

Early in the learning curve, we believe the simplest option is to set up and expose the surgical target in a systematic way and then insert the primary operative instrument (scissors, bipolar vessel sealer, etc.). In this way, the assistant grasper can be applied and maintain good exposure without movement of the assistant hand. Then the surgeon can focus on the dominant/operative hand. Until the surgeon is experienced with LESS, it is easy to get frustrated with retraction across the table or clashing when both hands are moving simultaneously. Therefore simpler procedures that can be accomplished in a straightforward routine process with little variation are most suited for learning a LESS approach. As the surgeon becomes more experienced, more complex procedures become easily feasible.

Specimen Extraction

One potential advantage of the LESS technique is for specimen extraction. Specimens can be more easily removed through the slightly larger skin incision (15–25 mm versus 12–15 mm for standard open laparoscopy). Extracorporeal morcellation can be accomplished through the larger incision. Some ports include a wound protector. These ports have a removable portion of the port that reveals a wound protector that facilitates easy extraction of specimens and allows easy replacement of the port, such as TriPort (Advanced Surgical Concepts, Wicklow, Ireland) and GelPoint (Applied Medical, Rancho Santa Margarita, California, USA). Because the camera and instruments enter through a single-port site, completely contained intracorporeal morcellation can be performed by inserting a large surgical bag through the port and then creating a pseudo-pneumoperitoneum directly within the bag. Purpose-built commercially available morcellation bags are under development. The camera, mechanical morcellator, and an assistant grasper can be inserted through the port and into the bag to perform the morcellation within a contained system. Any small pieces would remain in the bag. This would minimize or eliminate the risk of potential spread of benign or malignant tissue (Fig. 4.8).

Fig. 4.8

Contained morcellation in a bag. Internal view of the uterus and morcellator contained within a pseudo-pneumoperitoneum

Suturing

Laparoscopic suturing requires the most skill. Therefore, we recommend traditional suturing be considered only by those experienced with LESS. If laparoscopic suturing is necessary, we strongly suggest utilizing suturing assist devices such as the Endostitch (Covidien, Norwalk, Connecticut, USA), barbed suture, or Laparo-Ty (Ethicon Endo Surgery, INC. Cincinnati, Ohio, USA). In the case of a total hysterectomy, the authors suggest closing the vaginal cuff from a vaginal approach until the surgeon is experienced with LESS.

Challenges and Risks Specific to LESS

With the advent of LESS technique, instruments and ports have been developed to streamline the technique. However, many technical challenges still remain. When working within a small incision no larger than 3 cm, instrument crowding will always be an issue. Because of this, range of motion is restricted. To overcome this challenge, the surgeon may cross instruments; however, this may lead to counterintuitive motions.

LESS also leads to loss of triangulation due to the instruments and the camera all working within a small incision. This is a very important factor in order to safely perform laparoscopy. The basic surgical technique of traction-countertraction is best achieved with triangulation [17]. The best strategy to maintain the triangulation is to keep all instruments except the primary operating one away from the “target” zone. This zone is defined as the midline area that extends into the axial direction and in the highest plane above the abdominal wall [14]. This may be overcome by using instruments that already have a curve, therefore reducing the need for the surgeon to cross arms. Karl Storz and Olympus have manufactured curved instrumentation for LESS [12].

Another challenge with LESS is the learning curve. As with any new technique, new skill sets must be obtained. With LESS, a very high skill level is warranted, therefore potentially prolonging the learning curve and making it a difficult one. It is very important that surgeons adopting LESS be highly skilled and adept at conventional laparoscopy.

As with any laparoscopic technique, it is imperative that surgeons have thorough knowledge of electrosurgery to avoid electrosurgical complications. Surgeons should be aware of the different types of electrosurgical complications. There may be a theoretical increased risk of capacitive coupling when performing LESS. Working with instruments in close quarters may predispose them to insulation damage. Therefore, we recommend meticulous inspection of the instruments. Disposable electrosurgical instruments may have decreased risk of insulation damage and thus lower risk of direct coupling. We believe good technique should mitigate these risks.

Summary of Available Evidence

The feasibility of LESS in most laparoscopic procedures is demonstrated in multiple case reports and series in the medical literature. Several studies have addressed the potential advantages and disadvantages of LESS compared to conventional laparoscopy.

One of the first studies was performed by White et al. [18] in urologic patients. They looked at a series of eight patients in 2007–2008 who had undergone single-port retroperitoneal surgery and compared retrospectively to patients who had undergone retroperitoneal surgery with traditional laparoscopy. Based on their findings, they found no significant difference between the two groups, except that the LESS cohort had significantly decreased pain.

Most studies currently available comparing LESS hysterectomy to conventional laparoscopy have median uterine weights less than 300 g. However, Song et al. [19,20,21] demonstrated that LESS hysterectomy is also a safe and feasible option when removing a uterus weighing 500 g or more. Increasing uterine weight was associated with longer operative times and blood loss but was not associated with an increased need to convert to traditional laparoscopy [19,20,21]. With few exceptions, currently available studies demonstrate comparable operative times between LESS and standard laparoscopic technique. Escobar et al. [2, 3] examined the learning curve for LESS and found similar results when compared to published conventional laparoscopic learning curves.

There are few randomized trials. A recent meta-analysis of six randomized controlled trials by Song et al. [19,20,21] found no significant difference between any of their primary outcome measures including perioperative complications, conversation rates, postoperative pain, and cosmesis. Their conclusions were consistent with other studies with the exception of their assessment of cosmetic preferences. LESS may represent a superior alternative to traditional laparoscopy with respect to cosmetic results. At least three randomized controlled trials to date have shown superior patient satisfaction with LESS cosmetic results [19,20,21,22,23].

Another meta-analysis by Yang et al. [24] reviewed six randomized control trials and 12 retrospective studies, with a combined total of 3725 patients. This systematic review demonstrated that single-incision laparoscopy, compared to conventional laparoscopy, had higher procedure failure rates (3.59%), longer operative times, but shorter hospital course and faster return to bowel function. Additionally, this review showed no statistically significant differences in perioperative complications, postoperative pain, blood loss, or uterine weights. The higher failure rate of single-incision laparoscopy was due to the necessity of additional ports.

In 2015, Angioni et al. published a prospective case-control study exploring the perioperative outcomes between patients who underwent single-incision laparoscopic supracervical hysterectomy and conventional laparoscopic supracervical hysterectomy. The outcomes of this study demonstrated that patients in the single-incision group had longer operative times, shorter hospital course, decreased pain, and higher cosmetic satisfaction than the conventional laparoscopy group. These findings agree with the findings by Chen et al. [25] discussed earlier in this chapter. Additionally, a retrospective study by Yim et al. [26] studied the surgical outcomes and postoperative pain in patients undergoing hysterectomy either via single-port incision or conventional four-port laparoscopy. This study demonstrated a statistically significant difference in many parameters, including less intraoperative blood loss, shorter hospital stays, and faster recovery. Song et al. [19,20,21] performed a randomized controlled trial where they compared cosmetic satisfaction from LESS versus traditional laparoscopy and found that the LESS group had higher satisfaction rates.

Robotic LESS

LESS is also being introduced to the da Vinci (Intuitive Surgical, Sunnyvale, California, USA) robotic surgical sphere. Traditional robotic surgery has greatly improved postoperative pain while decreasing hospital stay and necessary analgesia when compared to open laparotomy. Escobar et al. [27] published a case report detailing an initial technique for robotic-assisted LESS. Since that time, a specialized robotic single-site platform with specific instrumentation has been introduced. Additional robotic LESS platforms are also being investigated.

Robotic-assisted LESS provides the advantage of enabling more rotational degrees of freedom, thereby reducing instrument crowding. It also enables triangulation, which is important to decrease the technical challenges associated with LESS. Additionally, this approach is also more ergonomically friendly [27].

Conclusion

LESS is a rapidly maturing minimally invasive modality that offers patients many benefits, including better cosmesis. As industries continue to develop newer technologies and instrumentation, the learning curve associated with this technique should decrease. It will be important for future residents, fellows, and practicing physicians to maintain a high level of dexterity in conventional laparoscopy prior to embarking on this modality. LESS still comes with technical challenges; however, as technology continues to advance, these should decrease. Studies have shown that LESS has favorable outcomes with patients and, therefore with continued study efforts, should be attainable for the majority of gynecologic surgeons.