Hybrid Appendectomy in Pediatric Appendicitis: A Comparative Analysis of Single-Port and Multiport Laparoscopic Appendectomy

Abstract

Background:

Hybrid appendectomy (HA) has the technical advantages of the excellent visual field provided by laparoscopic surgery and is fast and easy similar to open surgery. We aimed to compare the safety and effectiveness of HA with single- and multiport laparoscopic appendectomy (SPLA and MPLA) in pediatric patients with acute appendicitis.

Materials and Methods:

This retrospective study compared the short-term operative outcomes between HA, SPLA, and MPLA groups. From January, 2010 to December, 2019, 239 patients aged <12 years who underwent laparoscopic appendectomy for acute appendicitis were included. The primary outcome was the 30-day postoperative complication rate, stratified according to the modified Clavien–Dindo classification.

Results:

In 239 patients, HA was more frequently performed in patients with a low body mass index (17.42 versus 18.97 kg/m² in the SPLA group versus 18.44 kg/m² in the MPLA group, P = .029) and tended to be more frequently adopted in uncomplicated appendicitis. In uncomplicated appendicitis, the HA group had a significantly shorter operation time than the MPLA group (31.77 versus 40.09 min, P < .001), but had a comparable operation duration with the SPLA group. The rate of 30-day postoperative complications was not significantly different between the groups (HA 7.6% versus SPLA 7.8% versus MPLA 5.4%, P = .841). The postoperative time to resume water intake was significantly longer in the SPLA group than in the HA and MPLA groups (P = .008).

Conclusions:

HA showed a short operation time, fast functional recovery, and acceptable postoperative complication rate in patients with uncomplicated appendicitis and can be safely and effectively performed in these patients.

Introduction

Appendicitis is a prevalent non-neoplastic inflammatory disease and is most common in children between 10 and 19 years of age.^1,2 The treatment of choice for appendicitis is surgery, but open appendectomy has relatively severe postoperative pain, which requires a long hospital stay.³ Since the introduction of laparoscopic surgery for appendicitis by Semm,⁴ most surgeons prefer laparoscopic appendectomy as the treatment for acute appendicitis in children, because of the advantages of reducing postoperative pain and complications, reduced hospitalization, and improved cosmetic results.⁵ In recent years, new techniques have been developed to reduce the number of laparoscopic ports.⁶ Single-port laparoscopic appendectomy (SPLA) is a form of laparoscopic surgery performed by inserting one or more trocars through a small incision in the abdominal wall.

We have performed hybrid appendectomy (HA) in pediatric patients since 2010, in which the appendicitis is identified with a laparoscopic instrument and then the appendectomy is performed extracorporeally, similar to open appendectomy through an umbilical incision.⁷ HA has the advantages of improved visibility of laparoscopic surgery and the safety and speed of open surgery. Safety and efficiency are important for routine clinical application of HA in pediatric patients; however, no studies have compared multiport laparoscopic appendectomy (MPLA), SPLA, and HA. The aim of this study was to compare the clinical results of MPLA, SPLA, and HA in pediatric patients and to confirm the surgical safety and effectiveness of HA.

Materials and Methods

Patients

This retrospective comparative study included consecutive pediatric patients who underwent laparoscopic appendectomy for acute appendicitis at Chuncheon Sacred Heart Hospital, South Korea, between January 2010 and December 2019. The study protocol was approved by Hallym University Chuncheon Sacred Heart Hospital Institutional Review Board/Ethics Committee (CHUNCHEON 2020-08-003-001). Written informed consent was waived because this study was retrospective and observational. The study was conducted in accordance with the Declaration of Helsinki. We included pediatric patients with acute appendicitis who were diagnosed by preoperative abdominopelvic computed tomography scan or ultrasound. The exclusion criteria were (1) age >12 years; (2) open surgery; (3) an American Society of Anesthesiologists (ASA) score >3; (4) combined operation; and (5) loss to follow-up. After excluding 31 patients, 239 patients with acute appendicitis were included in the analysis (Fig. 1).

FIG. 1.

Study flow diagram. ASA, American Society of Anesthesiologists; MPLA, multiport laparoscopic appendectomy; SPLA, single-port laparoscopic appendectomy.

Surgical procedures

All surgical procedures were conducted by 8 surgeons who had previous experience with >300 laparoscopic appendectomies. Under general anesthesia, the patient was placed in a left-tilted supine position. The umbilicus was cleaned with 70% alcohol, and the abdomen was sterilized with iodine solution.

For HA, a 1.5 cm transumbilical incision was made. A homemade single-port platform consisting of an Alexis^® wound retractor (Applied Medical, Rancho Santa, CA) and a surgical glove was installed through the transumbilical entry. Three 5-mm trocars were inserted into the first and third fingers and thumb of the surgical glove for single-port laparoscopic procedures. Pneumoperitoneum with CO₂ gas up to 12 mmHg was established, and single-port laparoscopic exploration of the intraperitoneal cavity was performed with a 5-mm 0° or 30° scope and standard laparoscopic instruments. An inflamed appendix was identified and picked up outside the transumbilical entry. In some cases, the ileocecal duo was freed from the retroperitoneum for exteriorization, if needed. After removal of the surgical glove, an appendectomy was conducted by open methods.

For SPLA, a homemade single-port platform or commercial product was installed into the transumbilical entry and 5-mm 0° or 30° scope and rigid standard laparoscopic instruments were used in most cases. In some cases, articulated laparoscopic instruments were used to overcome the inherent limitations of SPLA, such as difficulty in making inter-instrumental triangulation and poor traction and countertraction for the target organs. After identifying the inflamed appendix, the appendiceal artery was ligated using a surgical energy device, and the appendix was ligated with one or two Endoloops (Ethicon, Inc., Cincinnati, OH). The resected appendix was retrieved through a single entry, and the intraperitoneal cavity was irrigated with normal saline.

For MPLA, a 10-mm trocar for the scope was inserted in the infra- or supraumbilical area, and two 5-mm trocars for the laparoscopic instruments were inserted in the left lower quadrant and suprapubic area. The technical details of the MPLA were identical to those of SPLA. The resected appendix was placed in the Lap Bag (SJ Medical, Paju, Korea) and removed through a periumbilical incision. A surgical drain was inserted through the transumbilical incision in the HA and SPLA, or through a 5-mm trocar site in the MPLA, as needed. The incision was closed with 2-0 Vicryl for the fascial layer and 3-0 nylon for the skin. Other technical details of the surgical procedure were determined according to the preferences of the individual surgeon.

Postoperatively, a second or third cephalosporin dose was administered intravenously in uncomplicated appendicitis, and intravenous metronidazole was added in complicated appendicitis cases. Water intake was usually resumed after first flatus, and progress of diet was determined by the surgeons based on the patient's appendix inflammation and postoperative condition. Discharge was permitted when the patient did not have fever or any evidence of postoperative surgical site infection, and when soft diet and pain were tolerable with oral pain killers.

Outcomes

Data were reviewed using electrical medical records and collected through the case reporting form. Corrected variables for baseline characteristics included sex, age, body mass index (BMI), ASA score, previous history of abdominal surgery, complete blood count with differential, and C-reactive protein (CRP) level at admission. The preoperative neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were calculated to assess the prognostic value of peritonitis. Data for operative results were type of appendicitis (uncomplicated or complicated); type of operation (HA, SPLA, or MPLA); operation time; conversion to open surgery; surgical drain insertion; 30-day postoperative complications, and grade according to the modified Clavien–Dindo classification⁸; postoperative time to functional recovery; postoperative length of stay; and mortality. The type of appendicitis was stratified according to intraoperative findings of perforated appendicitis and pathological results. Gangrenous or perforated appendicitis was classified as complicated appendicitis, regardless of abnormal fluid collection, abscess formation, or peritonitis.⁹

The primary outcome of the study was the 30-day postoperative complication rate. The definitions of postoperative complications were determined before data were collected in the study protocol. Wound seroma was defined as the presence of serous discharge at the incision site. Wound infection was defined as the presence of pus or purulent discharge that required frequent wound dressing. An intraperitoneal abscess was defined as abscess formation around the operation site or pelvis. Voiding difficulty was defined as urinary retention requiring insertion of an indwelling urinary catheter.

Statistical analyses

Statistical analyses were performed using Statistical Package for Social Science (SPSS, version 20.0, Chicago, IL), and the collected data were compared among the three groups (HA group versus SPLA group versus MPLA group). Categorical data were compared using Pearson's chi-square test. Continuous data were analyzed by Student's t-test and one-way analysis of variance (ANOVA), followed by post hoc Tukey's honestly significant difference multiple comparison test. Statistical significance was set at P < .05.

Results

A total of 270 consecutive patients with acute appendicitis were initially enrolled. After 31 patients were excluded, 239 patients (128 males and 111 females; mean age 8.53 years, range 3–12) were included in the analysis. HA was conducted in 93 patients, SPLA in 71, and MPLA in 75. Table 1 shows the patient baseline characteristics. Sex, age, ASA score, and history of abdominal surgery were similar in each group. However, BMI was significantly lower in the HA group, compared with SPLA (post hoc: HA 17.42 kg/m² versus SPLA 18.97 kg/m², P = .027). HA was less frequently conducted in complicated appendicitis than in SPLA and MPLA, but this difference was not statistically significant (P = .091).

Table 1.

Baseline Patient Characteristics

	HA (n = 93)	SPLA (n = 71)	MPLA (n = 75)	P
Male sex	45 (48.4%)	37 (52.1%)	46 (61.3%)	.235
Age, year	8.28 (3–12)	8.69 (4–11)	8.68 (4–11)	.329
BMI, kg/m²	17.42 (9.88–27.50)	18.97 (12.88–29.95)	18.44 (13.47–30.88)	.029
Post hoc HA versus SPLA P = .027; HA versus MPLS P = .202; SPLS versus MPLS P = .681
ASA score				.164
1	90 (96.8%)	71 (100%)	73 (97.3%)
2	3 (3.2%)	0 (0%)	2 (2.7%)
History of abdominal surgery	2 (2.2%)	2 (2.8%)	0 (0%)	.210
Type of appendicitis				.091
Uncomplicated	79 (84.9%)	51 (71.8%)	56 (74.7%)
Complicated	14 (15.1%)	20 (28.2%)	19 (25.3%)

Results are presented as numbers (%) or mean (range).

ASA, American Society of Anesthesiologists; BMI, body mass index; HA, hybrid appendectomy; MPLA, multiport laparoscopic appendectomy; SPLA, single-port laparoscopic appendectomy.

Uncomplicated appendicitis

In uncomplicated appendicitis, sex, age, ASA score, and previous history of abdominal surgery were similar among the three groups. BMI tended to be lower in the HA group, compared with that in the SPLA or MPLA group, but this difference was not statistically significant (HA 17.83 kg/m² versus SPLA 19.36 kg/m² versus MPLA 18.38 kg/m², P = .084). In the HA group, the mean white blood cell count at admission was significantly lower than that in the MPLA group and tended to be lower than that in the SPLA group (HA 11.66 × 10⁹/L versus SPLA 13.63 × 10⁹/L versus MPLA 13.84 × 10⁹/L, P = .017. Post hoc: HA versus SPLA, P = .065; HA versus MPLA, P = .030; SPLA versus MPLA, P = .983). The mean neutrophil count at admission was significantly lower in the HA group than in the SPLA and MPLA groups (HA 8.74 × 10⁹/L versus SPLA 11.00 × 10⁹/L versus MPLA 11.17 × 10⁹/L, P = .006). Post hoc: HA versus SPLA, P = .030; HA versus MPLA, P = .014; SPLA versus MPLA, P = .983). CRP, NLR, and PLR at admission were not significantly different among the three groups (Table 2).

Table 2.

Baseline Characteristics in Uncomplicated Appendicitis Patients

	HA (n = 79)	SPLA (n = 51)	MPLA (n = 56)	P
Male sex	39 (49.4%)	29 (56.9%)	36 (64.3%)	.223
Age, year	8.47 (3–12)	8.90 (4–11)	8.79 (4–11)	.412
BMI, kg/m²	17.83 (12.59–27.58)	19.36 (12.88–29.95)	18.38 (13.47–30.88)	.084
ASA score				.257
1	77 (97.5%)	51 (100%)	54 (96.4%)
2	2 (2.5%)	0 (0%)	4 (2.2%)
History of abdominal surgery	1 (1.3%)	2 (3.9%)	0 (0%)	.211
White blood cell count, 10⁹/L	11.66 (4.03–26.86)	13.63 (3.81–22.90)	13.84 (3.77–28.48)	.017
Post hoc HA versus SPLA P = .065; HA versus MPLA P = .030; SPLA versus MPLA P = .973
Neutrophil count, 10⁹/L	8.74 (1.50–27.90)	11.00 (2.40–19.80)	11.17 (2.40–26.30)	.006
Post hoc HA versus SPLA P = .030; HA versus MPLA P = .014; SPLA versus MPLA P = .983
Hemoglobin, g/dL	13.20 (11.30–15.40)	13.29 (11.50–15.90)	13.23 (10.90–14.90)	.798
CRP, mg/L	17.13 (0.20–68.60)	19.20 (0.44–103.10)	11.04 (0.10–29.00)	.309
NLR	6.91 (0.45–49.80)	8.60 (0.90–30.00)	7.83 (0.72–31.00)	.442
PLR	215.06 (52.42–975.00)	230.75 (71.03–1260.00)	216.07 (54.42–1075.00)	.853

Results are presented as numbers (%) or mean (range).

ASA, American Society of Anesthesiologists; BMI, body mass index; CRP, C-reactive protein; HA, hybrid appendectomy; MPLA, multiport laparoscopic appendectomy; NLR, neutrophil-to-lymphocyte ratio; PLR, platelet-to-lymphocyte ratio; SPLA, single-port laparoscopic appendectomy.

Table 3 lists the operative outcomes in the HA, SPLA, and MPLA groups. Operation time was significantly longer in the MPLA group than in the HA and SPLA groups (HA 31.77 min versus SPLA 31.27 min versus MPLA 40.09 min, P < .001. Post hoc: HA versus SPLA, P = .969; HA versus MPLA, P < .001; SPLA versus MPLA, P < .001). There was no conversion to open surgery in any of the groups. The rate of surgical drain insertion was similar in each group (HA 2.5% versus SPLA 2.0% versus MPLA 3.6%, P = .872).

Table 3.

Operative Outcomes in Uncomplicated Appendicitis Patients

	HA (n = 79)	SPLA (n = 51)	MPLA (n = 56)	P
Operation duration, minute	31.77 (15–70)	31.27 (15–65)	40.09 (22–80)	<.001
Post hoc HA versus SPLA P = .969; HA versus MPLS P < .001; SPLS versus MPLS P < .001
Conversion into open surgery	0 (0%)	0 (0%)	0 (0%)
Surgical drainage insertion	2 (2.5%)	1 (2.0%)	2 (3.6%)	.872
30-day postoperative complications
Overall	6 (7.6%)	4 (7.8%)	3 (5.4%)	.841
Grade 1	5 (6.3%)	2 (3.9%)	1 (1.8%)	.245
	Wound seroma (3); wound infection (2)	Wound infection (2)	Wound infection (1)
Grade 2	0 (0%)	2 (3.9%)	2 (3.6%)
		Intraperitoneal abscess (2)	Voiding difficulty (1); FUO (1)
Grade 3b	1 (1.3%)	0 (0%)	0 (0%)
	Intraperitoneal abscess (1)
Postoperative LOS, day	2.96 (2–5)	2.84 (2–6)	2.91 (2–7)	.768
Postoperative first flatus, day	1.25 (1–3)	1.48 (1–3)	1.14 (0–3)	.005
Post hoc HA versus SPLA P = .063; HA versus MPLS P = .477; SPLS versus MPLS P = .004
Postoperative resuming of sips, day	1.19 (0–3)	1.43 (1–3)	1.15 (0–2)	.008
Post hoc HA versus SPLA P = .030; HA versus MPLS P = .851; SPLS versus MPLS P = .011
Postoperative soft diet resumption, day	1.47 (1–3)	1.71 (1–3)	1.48 (1–4)	.088
Mortality	0 (0%)	0 (0%)	0 (0%)

Results are presented as numbers (%) or mean (range).

FUO, fever of unknown origin; HA, hybrid appendectomy; LOS, length of hospital stay; MPLA, multiport laparoscopic appendectomy; SPLA, single-port laparoscopic appendectomy.

The rate of overall 30-day postoperative complication did not differ among the groups (HA 7.6% versus SPLA 7.8% versus MPLA 5.4%, P = .841). The severity of postoperative complications according to the modified Clavien–Dindo classification was also not different among the groups (P = .245). However, wound-related complications were somewhat higher in the HA and SPLA groups than in the MPLA group (HA 6.3% versus SPLA 3.9% versus MPLA 1.8%). The postoperative time to first passage of flatus and to resume sips of water were faster in the HA and MPLA groups than in the SPLA group. However, the postoperative time to resume soft diet and postoperative length of hospital stay were not different among the three groups. No mortality was observed in any group.

Discussion

HA showed a short operation duration, fast functional recovery, and acceptable postoperative complication rate in patients with uncomplicated appendicitis. Scarless surgery is the goal of minimally invasive surgery. In particular, since scarring after surgery in pediatric patients can affect the psychosocial development of children, minimizing scarring is more important in pediatric surgery than in adults.¹⁰ Recently, efforts have been made to reduce the length of the incision, and for this, a method to reduce the number of ports was required.^6,11–13 However, since all instruments are inserted parallel to each other through a single incision, the surgical difficulty of not creating a triangular composition for proper traction appeared to be a limitation of the SPLA procedure. The difficulty of the surgical procedure causes disadvantages such as prolonged operation time,^6,14 increased conversion rate,¹⁵ and common additional port insertion.¹⁶

HA has the advantages of laparoscopic surgery and open surgery.⁷ In this study, HA was more common in uncomplicated cases, and pediatric patients aged 3–12 years were included in the analysis. This is because, in younger pediatric patients, the abdominal wall is thinner and the distance between the appendix and the umbilicus is shorter, making it easy to remove the appendix from the abdominal cavity in uncomplicated cases. In addition, decreased operation time can be induced by extracorporeal resection of the appendix with a simple procedure,¹⁷ and it is easy to educate trainees who are beginners in laparoscopic surgery, with a gentler learning curve.^18,19

Several studies demonstrated that HA shortens operation duration compared with SPLA or MPLA.^20–22 In this study, the operative times of HA, SPLA, and MPLA were all compared, and that of MPLA was longer than the other groups. In MPLA, more trocars having to be inserted, and wound repair of three or more incisions increases the operation time. In addition, the replacement time of various laparoscopic instruments (grasper, energy devices, endo-loop, endo-pouch, etc.) also increases the operation time. In general, the operation time reflects the degree of difficulty of the surgery. Owing to the technical difficulties of SPLA, it is inevitable to have a longer operation duration than HA for beginners who are not proficient in laparoscopic surgery. However, in the case of uncomplicated pediatric appendicitis, if a professional surgeon with experience in laparoscopic surgery performs the operation, as in this study, the operation time of HA and SPLA is shortened, so there may not be much difference in the operation time of the two procedures. In addition, the conversion rate can be reduced if the operation is performed by a laparoscopic specialist. Indeed, no open conversions were observed in this study.

In HA, there is a risk of wound infection at the incision site. In a recent large-scale study of single incision laparoscopic appendectomy, the superficial incision site infection rate was higher in the single incision group than in the conventional laparoscopic appendectomy group.²³ This suggests that the higher rate of wound infection may be due to the adverse effect of hypoxia on wound healing, due to small incisions and excessive traction.²³ In our study, wound-related complications were somewhat higher in the HA group with a small incision. However, there was no significant difference in the rate of 30-day postoperative complications as the primary outcome of the study in the HA, SPLA, and MPLA groups.

BMI, preoperative white blood cell count, and neutrophil count were lower in the HA group than in the other groups. This may suggest that the severity of preoperative appendicitis is related to the choice of surgical procedure, but there was no statistically significant difference in the inflammatory indices between the three groups. The recovery of bowel movement was significantly delayed in the SPLA group, possibly because the contact and manipulation of the gastrointestinal tract can increase due to the potential surgical difficulties of using instruments in a narrow space. Therefore, HA is more effective for rapid recovery after surgery for uncomplicated appendicitis in children.

To our knowledge, our study is the first to compare short-term surgical outcomes among three surgical approaches (HA versus SPLA versus MPLA). However, this study has several limitations. First, this study was retrospective in nature, and patients were not randomized. Second, the severity of appendicitis, which directly reflects the decision of the approach, lacks a universal scale and can potentially influence the analysis. Third, there are no data on long-term complications such as incisional hernia due to the lack of long-term follow-up data after surgery. Ultimately, randomized controlled trials are needed to validate the effectiveness and safety of HA.

In conclusion, HA is not associated with increased risk of postoperative complications and has a decreased operation duration and acceptable cosmetic results. This study demonstrated that HA is a valid, safe, and efficient surgical procedure in pediatric patients with uncomplicated appendicitis.

Footnotes

Authors' Contributions

J.H.H. and B.M.K. designed the study protocols and wrote the article. J.H.H., H.B.K., S.H.H., and B.M.K. collected the data and performed the statistical analysis. B.M.K. critically revised the article. All authors have read and approved the final version of the article.

Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

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