Background
This article describes a pure single-port laparoscopic appendectomy (SPLA). Appendectomy is one of the most frequently performed surgical procedures in the United States. The lifetime risk of appendicitis is 8.6% for males and 6.7% for females. [1]
From the first laparoscopic removal of an inflamed appendix by Kurt Semm in 1980 to today's standard laparoscopic technique, minimally invasive surgical approaches have been widely recognized as offering significant advantages, including reduced postoperative pain, a shorter recovery time, and better cosmesis. [2]
The traditional approach to laparoscopic appendectomy employs three ports. Over the past decade, successful attempts to perform the procedure with fewer ports have been reported. The medical literature has described two-port techniques, [3] hybrid approaches, [4, 5] and single-port assisted techniques. [6, 7, 8]
The two-port appendectomy technique is very similar to the standard three-port technique, except that one port provides access for a rigid endoscope with a working channel, whereas the second port provides access for a grasping instrument that is used to retract the appendix. [3]
In the hybrid technique, the appendix is pulled through the umbilicus, and a traditional open appendectomy is then performed extracorporeally. [9, 10, 11, 12]
The single-port assisted technique is intriguing in that a stitch is placed through the anterior abdominal wall to pull the appendix to the abdominal wall; this creates the tension necessary for performing the appendectomy intracorporeally. [6, 13]
The total single-port approach, as described in this article, employs a technique resembling that of a puppeteer. [14] A "pulley" is constructed in the form of a loop to the anterior abdominal wall. This loop is used as an axle over which the appendix is elevated with a string to the abdominal wall; in this way, it compensates for the absence of the additional port traditionally needed for retraction of the inflamed appendix.
Although SPLA or multiport laparoscopic appendectomy (MPLA) is the gold standard for management of acute appendicitis, the laparoscopic approach may not yet be cost-effective in the developing world. The surgical-glove port single-incision laparoscopic appendectomy (SGP-SILA) has been proposed as a viable option in low- and middle- income countries in place of the conventional techniques and has been found to be a good alternative. [15]
Indications
Indications for single-port appendectomy include acute appendicitis, recurrent appendicitis, and chronic appendicitis. Whenever a single-port appendectomy is performed, it is important to maintain a low threshold for conversion to a standard laparoscopic or open approach. [11]
Contraindications
Absolute contraindications for SPLA include signs of perforation, pregnancy, and an American Society of Anesthesiologists (ASA) classification of 3 or 4. Patients with these contraindications are not suitable candidates for SPLA, and a standard laparoscopic appendectomy or open appendectomy should be performed instead.
Relative contraindications for SPLA include a retrocecal-lying appendix (because of the difficulty of mobilizing the appendix adequately) and adhesions from previous surgical procedures.
Technical Considerations
Anatomy
Anatomic considerations are of substantial clinical importance in the context of acute appendicitis; the location of the appendix often determines the symptoms and the site of pain if the appendix becomes inflamed.
The vermiform appendix is a vestigial structure that can range from less than 1 cm in length to more than 30 cm; on average, it is 6-9 cm long. Embryonically, the appendix first appears in the eighth week of life as an outgrowth of the terminal portion of the cecum. Throughout development, the cecum grows faster than the appendix does; as a result, the appendix is generally displaced more medially toward the ileocecal valve.
The three taeniae coli converge at the junction of the cecum with the appendix; this junction can and should be used as a landmark to identify the appendix. Appendiceal absence, duplication, and diverticula have all been described.
The appendiceal base is always just at the base of the cecum distal to the ileocecal valve. The tip of the appendix, however, has a more variable location and can be found in several different positions, including retrocecal, pelvic, subcecal, preileal, and right pericolic.
Outcomes
Studies comparing single-port and conventional laparoscopic techniques have not shown consistent findings.
Liang et al concluded that SILA resulted in rapid recovery, no increase in pain or complications, and a better cosmetic outcome. [16] Choi et al found that postoperative pain outcomes between SILA yielded reduced pain as compared with conventional laparoscopic appendectomy. [17] Qiu et al concluded that SPLA had no benefits over conventional laparoscopic appendectomy. [18] Antoniou et al concluded that the two methods showed similar postoperative morbidity and wound infection. [19]
With regard to the use of single-port appendectomy in pediatric populations, Zhang et al found that in children, single-port appendectomy, though safe and feasible, appeared to offer no significant advantages. [20] A transumbilical approach has also been found to be beneficial. [21, 11, 12]
In a study of conventional single-port appendectomy in children with complicated appendicitis, Karakus et al found the procedure to be associated with a reasonable operating time, a shorter hospitalization period, reduced rates of postoperative wound infection and adhesive intestinal obstruction, and equivalent operative costs as compared with open appendectomy and MPLA. [22]
A report evaluating patient-surveyed scar assessments with SPLA versus MPLA showed that the Patient Scar Assessment Questionnaire (PSAQ) administered to patients 6 weeks after surgery favored the SPLA approach. [23] There were significant differences in total score (48 vs 55), appearance (15 vs 18), and consciousness (8 vs 10); however, there were no significant differences with respect to satisfaction with appearance or symptoms scale.
Advances in surgical equipment and protocols for SPLA have led to improved care of patients with acute appendicitis in terms of hospital costs, number of surgical incisions, and postoperative hospital stay. [24] The issues that persist are longer single-incision length, higher complication rates, and longer operating time. Accordingly, to optimize outcomes, surgical instruments and techniques should be rationally chosen on the basis of individual disease status and specific patient needs.
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Single-port appendectomy: retraction of appendix.
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After string attached to appendix is threaded through loop, it is brought out through port for extracorporeal manipulation by surgeon.
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String is placed around appendix.
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Placement of surgical tie around appendix.
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String attached to appendix is threaded through loop.
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Exposure of appendiceal base.
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View of appendiceal base after placement of surgical tie.
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Dissection of mesoappendix.
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Placement of appendix in endoscopic specimen retrieval bag.
