Jeffrey J. Runge, DVM, Diplomate ACVS
In both animals and humans, minimally invasive surgery has revolutionized modern surgical practices; it has significantly changed modern surgical thinking, surgical techniques, and patient care.1 Compared with similar open procedures,2 these new techniques are readily available for companion animals with proven advantages, such as:
- Decreased postoperative pain3
- Improved postoperative recovery.
As the number and variety of minimally invasive procedures increase and become proven as safe alternatives to open surgery, practitioners should ensure that they continually educate pet owners about the entire range of treatment options available for their pets.
REDUCED PORT SURGERY
Due to the progressive ingenuity within the laparoscopic environment, efforts in human and veterinary surgery are now directed at further minimizing morbidity. One of the emerging concepts is a platform called reduced port surgery. This platform has led to the development of new techniques, devices, and instruments that allow laparoscopic procedures to be performed through a small single skin incision 1- to 2-cm in length (often hidden within the umbilicus of human patients).
This platform is an advanced minimally invasive operative approach that may be considered a bridge between conventional multiport laparoscopic surgery and natural orifice transluminal endoscopic surgery (NOTES),4 which uses natural orifices, such as the mouth, anus, and vagina, for access into the abdomen to avoid making a skin incision. NOTES may represent the ultimate goal of avoiding external incisions completely in minimally invasive major abdominal surgery.
Reduced port surgery was pioneered in Philadelphia by Paul G. Curcillo, MD, and Stephanie King, MD, in 2007; at that time their group deemed the technique single port access (SPA).5 The SPA technique enabled the reduced port surgical platform to enter mainstream human laparoscopy and gain widespread acceptance as a safe and viable platform for laparoscopic surgery. Seeing an opportunity to extend the breadth of this new platform, a collaborative effort between human surgeons (Curcillo and King) and a veterinary surgeon (Runge) in 2010 enabled the SPA technique to be adapted for clinical veterinary laparoscopy (Figure 1).6
Since the first description of SPA cholecystectomy,7 a wide array of commercially available multitrocar ports have become available. This has led to two platforms available for reduced port surgery. These platforms come with their own acronyms as well; hence, the commercial entities who have developed these ports have adopted their own trademark nomenclature for the laparoscopic techniques used through their multitrocar ports.
Currently, the two platforms are the:
- Single port access (SPA) technique platform
- Single port device platforms.
The SPA technique maintains use of standard instruments and multiple trocars inserted through a single skin incision (ie, port of entry) with multiple fascial incisions within the abdominal wall. The single port device platforms utilize novel multitrocared ports that can be placed through a larger fascial incision.
Descriptions for the use of commercially available multitrocar ports are present throughout the human laparoscopic literature and include but are not limited to:
- SILSTM port (Single Incision Laparoscopic Surgery); covidien.com (Figure 2)
- TriPort+TM access system for laparo-endoscopic single-site surgery (LESS); olympusamerica.com (Figure 3)
- GelPOINTTM access system; appliedmedical.com (Figure 4).
At present, all techniques (SPA and single port device platforms) have been demonstrated to be equally as effective in humans with respect to operative times, outcomes, and complications compared to multiport laparoscopy. There has not been a strong demonstration showing any benefit in terms of pain, recovery, or return to activity compared to multiport laparoscopy.
SINGLE PORT ACCESS TECHNIQUE PLATFORM
In 2007, SPA introduced a novel approach to abdominal entry for human laparoscopic procedures. A single, often concealed, skin incision through the umbillicus5 (generally < 18 mm in length) was used and a wide variety of human surgical procedures have been successfully performed, including cholecystectomy7 and oophorectomy.9
In 2010, our group at University of Pennsylvania School of Veterinary Medicine reported on the successful use of the SPA technique in canine patients.6 SPA maintains standard instrumentation and techniques and cost control, while preserving safe dissection techniques defined by multiport laparoscopy.10,11 With the SPA technique, the large triangle of trocar positioning seen in multiport laparoscopy is simply moved—the trocars are arranged in a smaller triangle completely within a single incision.
Step by Step: SPA Technique
- The SPA technique in canine patients is accomplished by creating a 1- to 2-cm incision midway between the umbilicus and the xyphoid.
- Using the Hassan abdominal access technique (direct trocar insertion without prior pneumoperitoneum), a 5-mm blunt laparoscopic trocar is inserted into the abdomen. Using minimal blunt dissection, 2 subcutaneous tunnels are undermined approximately 1- to 2-cm laterally on either side of the initial camera trocar.
- Through these tunneled incisions, 2 additional, very low profile (head size < 2 cm) 5-mm trocars (Hunt trocar, coopersurgical.com) are inserted caudolaterally; then carefully inserted into the abdominal wall using the sharp trocars.
- The 3 trocars are arranged in a triangulated position, each through separate fascial openings, but exiting through the same skin incision (Figure 1).
Switching to the SPA Surgical Technique
The SPA surgical technique introduces an innovative approach to abdominal entry and trocar placement through a single skin incision. This technique is based on standard exposure and dissection of multiport laparoscopy. It requires the surgeon to learn only one new method of access and then become comfortable performing the familiar dissection and surgical techniques with a new arrangement of standard, familiar instruments in close proximity.5,7,10
The efficacy and learning curve of this access system in veterinary surgery is currently being evaluated clinically for select procedures in canine and feline patients at University of Pennsylvania School of Veterinary Medicine (Figure 5).
SINGLE PORT DEVICE PLATFORMS (Multitrocar Ports)
SILS Port (Single Incision Laparoscopic Surgery)
The SILS multitrocar device is an FDA-approved access system used for reduced port laparoscopic surgery in humans. This port allows the clinician to simultaneously pass multiple instruments through a single access point (Figure 2).
The SILS multitrocar port is packaged and supplied as a sterile single-use device. It is a blue flexible port made from hourglass-shaped elastic polymer that conforms and fits snugly within the abdominal incision.
- The port contains 4 openings: 1 for insufflation and 3 to accommodate separate rigid trocars from 5 to 12 mm in size.
- The port is inserted through a 2-cm fascial incision by placing 2 staggered, curved Rochester carmalt clamps at the base of the port and directing the tips of the carmalt into the abdomen.
- The compressibility of the port allows it to expand and fit snugly in the fascial incision, extending down to the level of the peritoneum.
- The height of the rigid trocars that pass through the port is staggered, allowing the heads to have freedom of movement without touching.
- Specimen and liberated tissue can be extracted either during or after the procedure is completed by gently pulling the SILS port out of the incision.
- The port can be repeatedly inserted or removed through the fascial incision during the procedure.
As with all laparoscopic surgery, adequate visualization of the operative field is essential. A basic tenet of laparoscopic surgery requires a degree of triangulation of instruments in order to produce adequate intracorporeal working space for dissection and manipulation of tissue.
When using the SILS port with standard laparoscopic instruments, the parallel and close proximity of the left and right hands may result in crowding, ultimately preventing adequate triangulation. This problem is offset by using novel instruments that have the capability to articulate (Figure 6).
- The technique of criss-crossing 2 reticulating instruments (“cross handed”) has been described to perform various SILS procedures.12
- Others have advocated using 1 reticulating instrument and 1 straight instrument.13
In veterinary medicine, the efficacy and limitations of the SILS multitrocar port with use of articulating and straight instruments is currently under evaluation.
Triport+ Access System for Laparo-Endoscopic Single-Site (LESS) Surgery
The Triport+ multitrocar device is an FDA-approved multitrocar access port used for reduced port surgery in humans (Figure 3). It allows the clinician to pass multiple instruments simultaneously through the port’s single incision (Figure 7).
This port is packaged and supplied as a sterile single-use device.
- In animals, this port requires a 1.5- to 2-cm fascial incision along the midline at the level of the umbilicus. The sheath of the multitrocar port is inserted through this fascial opening into the peritoneum with an introducer device.
- The sheath of the Triport+ has a self-expanding ring, which allows the base of the port to remain inside the peritoneum. The sheath is also adjustable; the port sits flush against the skin regardless of abdominal wall thickness or patient size.
- The outer portion of the port has three 5-mm ports and a 10-mm port (reducible to 5 mm), enabling a surgeon to perform a 4-port laparoscopic procedure. The ports have a duckbill-lip seal, which facilitates introduction and removal of instruments while maintaining a pneumoperitoneum.
- The ports are also flexible and accommodate different types and sizes of laparoscopic instruments, including those that are curved or bent. The TriPort+ multitrocar device has specifically designed curved instruments that enable triangulation within the abdomen. The curves and bends allow the instruments to pass into the abdomen through any of the flexible ports.
The system can be used in combination with a deflectable tip EndoEYETM optical camera (olympusamerica.com) for visualization (Figures 7 and 8). This optical system allows the camera operator to visualize organs from different angles, bending and flexing the scope tip as needed to create the necessary view of the surgical procedure.
The outer portion of the port can be removed without having to disengage the inner sheath from its snug fit against the abdominal wall. This allows for specimen retrieval without port removal.
The clinical benefits and limitations of the TriPort+ access device are being assessed in both human and veterinary surgery. Efficacy in veterinary patients is currently being clinically evaluated in select canine and feline cases at University of Pennsylvania School of Veterinary Medicine. As of yet, no data exist within the veterinary literature comparing Triport+ to standard multiport laparoscopy.
GelPOINT Access System
The GelPOINT multitrocar device (Figure 4) is an FDA-approved multitrocar access system used for reduced port surgery in humans.
- This multitrocar port consists of 3 components: Alexis wound retractor, GelSeal cap, and a set of 4 instrument cannulas.
- The supplied wound retractor has a large distal ring that can accommodate a range of abdominal incisions from 1.5 to 7 cm as well as a wide range of abdominal wall thicknesses. The wound retraction sheath enables 360o of atraumatic retraction.14
- The outer portion of this multitrocar port is composed of flexible GelSeal that acts as a resealable barrier.
- The GelSeal allows all cannulas to be repeatedly introduced and removed during a procedure.
- Specimen removal can be safely repeated during a procedure without removing the Alexis portion of the port, which provides a protective barrier for the incision site (Figure 9).14
- The port requires a fascial incision approximately 2 cm wide; however, this incision can be increased up to 5 cm, allowing removal of larger tissues, such as a spleen or kidney.
- The port is typically placed midline at the level of the umbilicus; however, in my experience, the port can be placed in alternate locations off the midline (eg, the flank region), accommodating such procedures as reduced port nephrectomy or splenectomy.
- To place the port, the Alexis retractor is inserted through the skin incision.
- Once the Alexis portion enables sufficient 360° radial wound retraction, the GelSeal portion of the port is then latched onto the outer ring of the Alexis.
- The ports are placed through the GelSEAL portion as needed once the desired arrangement of instruments is determined for that particular procedure.
The clinical benefits and limitations of the GelPOINT access system are currently being evaluated in veterinary surgery. Select canine patients are currently participating in trials at University of Pennsylvania School of Veterinary Medicine. To date, no data in the veterinary literature compares this system to standard multiport laparoscopy.
Current efforts in human laparoscopy are focused on reducing overall surgical morbidity and veterinary laparoscopy has continued to follow suit. However, reduced port surgery in veterinary medicine is in its infancy. Further refinements in instrumentation and operative techniques are required before this method of surgical access can be widely accepted.
Ongoing advancements in human laparoscopy have inspired our group to improve existing minimally invasive surgical techniques and evaluate the reduced port platform’s use in veterinary laparoscopy (Tables 1 and 2). Our initial experience is promising. The combination of successful use of SPA techniques in canine patients and multitrocar devices in cats and dogs for specific laparoscopic procedures have provided evidence that, with appropriate patient selection, the reduced port platforms have a role in companion animal veterinary medicine.
LESS = laparo-endoscopic single-site surgery; NOTES = natural orifice transluminal endoscopic surgery; SILS = single incision laparoscopic surgery; SPA = single port access
Figure 2: Courtesy of Covidien (covidien.com)
Figures 3, 7, and 8: Courtesy of Olympus America, Inc (olympusamerica.com)
Figure 4: Courtesy of Applied Medical (appliedmedical.com)
- Darzi A, Munz Y. The impact of minimally invasive surgical techniques. Annu Rev Med 2004; 55(1):223-237.
- Davidson EB, Moll HD, Payton ME. Comparison of laparoscopic ovariohysterectomy and ovariohysterectomy in dogs. Vet Surg 2004; 33:62-69.
- Culp WTN, Mayhew PD, Brown DC. The effect of laparoscopic versus open ovariectomy on postsurgical activity in small dogs. Vet Surg 2009; 38(7):811-817.
- Kalloo AN, Singh VK, Jaggannath SB, et al. Flexible transgastric peritoneoscopy: A novel approach to diagnostic and therapeutic interventions in the peritoneal cavity. Gastrointest Endosc 2004; 60(1):114-117.
- Podolsky ER, Rottman SJ, Poblete H, et al. Single port access (SPA) cholecystectomy: A completely transumbilical approach. J Laparoendosc Adv Surg Tech A, 2009; 19(2):219-222.
- Runge JJ, Curcillo PG, King SA, et al. Reduced port surgery: Single port access (SPA) technique for laparoscopic canine ovariectomy. Vet Endosc Soc Proc, 2011.
- Curcillo PG, Wu A, Podolsky E, et al. Single port access (SPA) cholecystectomy—initial validation of a single incision approach. Soc Am Gastrointest Endosc Surg Proc, 2008.
- Gill IS, Advincula AP, Aron M, et al. Consensus statement of the consortium for laparoendoscopic single-site surgery. Surg Endosc 2010; 24(4):762-768.
- King SA, Atogho A, Podolsky E, Curcillo PG. Single port access (SPA) bilateral oophorectomy and hysterectomy. Laparosc Today 2008; 7:2.
- Podolsky ER, Rottman SJ, Curcillo PG. Single port access (SPA) cholecystectomy: Two year follow-up. J Soc Laparosc Surg 2009; 13(4):528-535.
- Curcillo PG, Wu AS, Podolsky ER, et al. Single port access (SPA) cholecystectomy: A multi-institutional report of the first 297 cases. Surg Endosc 2010; 24(8):1854-1860.
- Romanelli JR, Roshek TB, Lynn DC, Earle DB. Single port laparoscopic cholecystectomy: Initial experience. Surg Endosc 2010; 24(6):1374-1379.
- Stolzenburg JU, Kallidonis P, Hellawell G, et al. Technique of laparoscopic-endoscopic single-site surgery radical nephrectomy. Eur Urol 2009; 56(4):644-650.
- Horiuchi T, Tanishima H, Tamagawa K, et al. Randomized controlled investigation of the anti-infective properties of the Alexis retractor/protector of incision sites. J Trauma 2007; 62(1):212-215.
Jeffrey J. Runge, DVM, Diplomate ACVS, is a lecturer in small animal surgery at University of Pennsylvania School of Veterinary Medicine. He specializes in companion animal and exotic species surgery and focuses on laparoscopic and thoracoscopic minimally invasive surgery. Through ongoing collaboration with leading human laparoscopic surgeons, Dr. Runge and the University of Pennsylvania School of Veterinary Medicine have become leaders in veterinary reduced port surgery. Dr. Runge’s group applies newer human laparoscopic single-site techniques, such as single port access (SPA), single incision laparoscopic surgery (SILS), and laparo-endoscopic single-site surgery (LESS), to minimally invasive surgery for companion animals. Dr. Runge lectures internationally on both single port and multiport laparoscopic surgery.