Series
Studydesign
Number of patients
Included inflammatory disease?
MeanBMI(kg/m2)
Conversion multi-port laparoscopy (%)
Conversion open (%)
Mean operative time (Min)
Length of stay (days)
Morbidity (%)
Mortality (%)
Champagne et al.
Prospective Case Control
165
Yes
27
11
2.4
135
4.3
26.1
0.6
Geisler et al.
ProspectiveCase Series
102
Yes
26
17.6
1
99
5.9
38
1
Miller et al.
Prospective Case Series
31
Yes
26.5
3.2
9.6
164
5.7
22.6
0
Moftah et al.
Prospective Case Series
33
Yes
21.3
0
15
120
6
39
0
Olson et al.
Retrospective Case Control
20
Yes
24.8
0
10
218
7.9
40
0
Rieger et al.
Prospective Case Series
7
No
24.3
0
0
89
5.4
0
0
Rijcken et al.
Retrospective Case Control
20
Yes
21.5
0
5
137.4
9
20
0
Rizzuto et al.
Prospective Case Series
488
Yes
29
0.6
0.2
103
5
0.6
0
Ross et al.
Prospective Case Series
39
Yes
25.6
7.7
5.1
120
4.4
7.7
0
Vestweber et al.
Prospective Case Series
329
Yes
26.3
3.4
6.1
154
8
18.3
0.3
It also is important to remember that this technology is still in its relatively early stages. As such, the bulk of the data currently available is retrospective or prospectively collected cohorts in which surgeons control the population, and is no doubt the subject of significant selection bias—as the majority of included patients had low BMI, no bulky malignancy, and no inflammatory disease, and the operations were performed by surgeons who were very experienced in the technique.
Indications
While SILS uses only one incision in the abdominal wall and the entire procedure is performed through this opening and traditional laparoscopy uses multiple ports, the basic tenets of minimally invasive surgery remain the same: adequate exposure, tension and counter-tension, triangulation, and safe tissue handling. Major differences may include the use of instruments and devices tailored for in-line viewing, differences in ergonomics, and relative propensity for instruments to cross with SILS. However, it is important to again point out that all types of colorectal operations have been performed safely and effectively through a SILS procedure, from a stoma to a total proctocolectomy and ileal pouch-anal anastomosis [8, 11, 12]. While opponents may claim SILS is a “gimmick” or marketing maneuver, the reality is that SILS has become the preferred approach for many surgeons.
Preoperative Planning
Regardless of the operative approach used, every patient should undergo a thorough history and physical examination, along with a generalized risk stratification to determine the potential for morbidity and mortality (Table 2.2). In addition, patients undergoing a major abdominal operation should, in general, have a complete blood count, chemistry panel and carcinoembryonic antigen [(CEA) in cases of malignancy]. Additional radiological and endoscopic examinations will allow for appropriate localization of the disease and staging for cases of malignancy. Surgeons should make a special point of ensuring prior tattooing with India ink or clips has been performed, as reliance on descriptive reports with regard to tumor location is fraught with potential for error. While still controversial, the authors prefer a mechanical bowel preparation with oral antibiotics for all colorectal resections. Intravenous antibiotics should be given perioperatively for all patients in conjunction with appropriate Surgical Care Improvement Project (SCIP) guidelines. Intraoperatively, it is important to ensure appropriate blood glucose control, normothermia, and that supplemental oxygen therapy is given [13].
Table 2.2
Revised cardiac risk index
Risk factors | |
1. High-risk type of surgery (intraperitoneal, intrathoracic, or suprainguinal vascular procedures) | |
2. Ischemic heart disease | |
3. Congestive heart failure | |
4. History of cerebrovascular disease | |
5. Insulin therapy for diabetes | |
6. Preoperative serum creatinine >2.0 mg/dl | |
Risk classification (1 point is assigned to each risk factor present) | Rates of major cardiac complications a |
Class 1 (0 points) | 0.5% |
Class II (1 point) | 1.3% |
Class III (2 points) | 3.6% |
Class IV (≥ 3 points) | 9.1% |
Considerations in Select Populations
Ultimately, all patients eligible for laparoscopy may be considered potential candidates for SILS in the right hands. While there may be no definitive contraindications for SILS, the surgeon should carefully consider each patient and procedure individually when deciding the appropriate surgical approach. Three patient populations pose particular challenges and deserve special consideration: the obese, those with inflammatory disease, and colorectal cancer patients.
SILS and Obesity
It is well understood that obesity, particularly visceral obesity, significantly increases the complexity of any laparoscopic procedure (Fig. 2.1). While the effect of obesity on outcomes following traditional laparoscopy is still an area of active investigation, evidence clearly supports that traditional multi-port laparoscopy is safe and feasible in obese patients, with outcomes similar to those of non-obese patients, especially when compared to open surgery [14–23].
Fig. 2.1
Obese patients may amplify challenges in the application of minimally invasive approaches
SILS is undeniably more technically challenging than traditional multi-port laparoscopy in this population, amplifying the effect of obesity on the difficulty of the procedure. The presence of high amounts of visceral fat makes the identification of the correct surgical plane more difficult and impedes proper surgical exposure (Fig. 2.2). Therefore, it is not surprising that much of current literature demonstrating the feasibility of SILS has centered on non-obese patients [3, 7–10]. It is revealing that in two separate systematic reviews of single-incision laparoscopic colectomy, the mean BMIs of patients included in the literature were found to be 25.5 and 25.8 kg/m2, respectively [24, 25].
Fig. 2.2
Sigmoid colon with a large amount of visceral fat. The straight line marks location of the inferior mesenteric artery and the circle identifies the sacral promontory
Nevertheless, there have been some published data on short-term outcomes of obese patients undergoing single-incision laparoscopic colectomy. Regrettably, these studies are all based on small patient numbers and the data are somewhat conflicting. In some, visceral obesity has been associated with longer operative times, increased blood loss, and was a primary factor leading to conversion to an open procedure [26, 27]. Contrarily, others have found no difference in conversion rate, operative time, estimated blood loss, time to return of bowel function, length of stay, or reoperation and readmission rates between multi-port and single-port approaches in obese patients [15, 28]. This contrast more likely highlights the variations in surgeon experience and expertise with this approach.
Key points to consider are adhering to the simple principles of all minimally invasive surgery: proper exposure, appropriate definition of anatomy, apposite tissue handling, and technically sound operative steps. One of the initial major issues encountered is the lack of domain when establishing a pneumoperitoneum with any minimally invasive approach that often occurs in the obese patient (Fig. 2.3). Positioning the omentum in the upper abdomen, rotating the operating table to the extremes to facilitate gravity effects on the bowel, and “flipping” the mesentery of the small bowel to allow it stay in place are tricks to help ensure adequate exposure (Fig. 2.4).
