J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website http://www.jocmr.org

Original Article

Volume 11, Number 1, January 2019, pages 56-64

Acute Appendicectomy or Conservative Treatment for Complicated Appendicitis (Phlegmon or Abscess)? A Systematic Review by Updated Traditional and Cumulative Meta-Analysis

Figure 2. (a) Overall duration of hospital stay of the whole sample. (b) Overall duration of hospital stay of RCTs. (c) Overall duration of hospital stay of the high-quality RCTs.

Figure 3. (a) Abdominal/pelvic abscesses of the whole sample illustrating favor of the conservative treatment. (b) Statistically non-significant studies of St Peter et al [33] and Mentula et al [34] demonstrating an impact of preference for laparoscopic appendicectomy compared to conservative treatment.

Figure 4. Traditional and cumulative meta-analysis of complicated appendicitis. (a) Traditional meta-analysis; (b) cumulative meta-analysis.

**Table 1.** Characteristics of the Included Studies
Authors year study design	AA (n)	CM (n)	Age AA-CM (years ± SD)	Inclusion criteria*	Matching criteria**	NOS
AA: acute appendicectomy; CM: conservative management; RS: retrospective study; RCT: randomized controlled trial; NOS: Newcastle-Ottawa scale; NR: non-reported; HQ: high quality; ASA: American Society of Anesthesiologists. Inclusion criteria: 1 = pediatric cases, 2 = adults, 3 = clinical symptoms, 4 = appendicular mass, 5 = appendicular abscess, 6 = perforated appendix. *Matching criteria: 1 = sex, 2 = age, 3 = duration of symptoms, 4 = ASA, 5 = body mass index, 6 = heart rate, 7 = white blood cells, 8 = temperature, 9 = C-reactive protein, 10 = size of appendicular mass.
Mentula et al [34], 2015 RCT	30	30	45 ± 14 46 ± 13.75	2, 3, 5	1, 2, 3, 4, 5, 7, 9, 10	9
St Peter et al [33], 2010 RCT	20	20	10.1 ± 4.2 8.8 ± 4.2, P = 0.31	2, 3, 4, 5	1, 3, 5, 7, 8	9
Aranda-Narvaez et al [32], 2010 RS	15	15	35.8 ± 12 35.4 ± 12	2, 3, 4, 5	1, 2, 3, 4, 6, 7, 8, 9	7
Roach et al [31], 2007 RS	60	32	NR	1, 3, 4, 5, 6	1, 2, 7, 8	7
Henry et al [30], 2007 RS	48	48	8.5 - 9	1, 3, 6	1, 2, 7, 8	8
Erdogan et al [29], 2005 RS	19	21	8	1, 3, 4	1, 2, 3, 5, 7, 8	5
Kumar et al [28], 2004 RCT	20	20	31.6 ± 14.6 26 ± 12.4	3, 4	2	5
Ho et al [27], 2004 RS	27	32	12 - 11	1, 3, 4, 6	1, 2, 3, 5, 7, 8	9
Brown et al [26], 2003 RS	36	68	31 - 35	2, 4, 5	1, 2, 4, 6, 7, 8	7
Samuel et al [25], 2002 PS	34	48	7 - 7	1, 3, 4, 5	1, 2, 3	7
Tingstedt et al [24], 2002 RS	43	50	42 - 50	2, 3, 4, 5	1, 2, 3, 6, 7, 8	8
Oliak et al [23], 2001 RS	67	88	31 - 35	2, 3, 4, 5	1, 2, 3, 4, 6, 7, 8	9
Bufo et al [22], 1998 RS	46	41	10 - 11	1, 3, 4, 5, 6	1, 2, 3, 7, 8	8
Handa et al [21], 1997 RS	8	6	7 - 8	1, 3, 5	1, 2, 3, 7	7
Hume et al [20], 1995 RS	78	69	48 - 43	2, 3, 4, 5	1, 2	6
Gahukambe et al [19], 1993 RS	7	59	< 12	1, 3, 4	2	5
Hoffmann et al [18], 1991 RS	19	28	35 - 37	1, 2, 3, 4, 5	1, 3	4
Lewin et al [17], 1988 RS	95	98	49	2, 3, 4, 5	1, 2, 3	4
Gomez-Lorenzo et al [16], 1987 RS	89	106	39 - 53	1, 2, 3, 4	1, 2, 3, 7, 8	8
Foran et al [15], 1978 RS	13	30	30 - 34	2, 3, 4, 5	2, 3, 7, 8, 9	8
Gastrin et al [14], 1969 RS	36	23	< 15	1, 3, 4, 5	1, 2, 3	6
Pooled n = 1,864	810 (43%)	932 (57%)				HQ = 14

Table 1. Characteristics of the Included Studies

Authors year study design

AA (n)

CM (n)

Age AA-CM (years ± SD)

Inclusion criteria*

Matching criteria**

NOS

AA: acute appendicectomy; CM: conservative management; RS: retrospective study; RCT: randomized controlled trial; NOS: Newcastle-Ottawa scale; NR: non-reported; HQ: high quality; ASA: American Society of Anesthesiologists. *Inclusion criteria: 1 = pediatric cases, 2 = adults, 3 = clinical symptoms, 4 = appendicular mass, 5 = appendicular abscess, 6 = perforated appendix. **Matching criteria: 1 = sex, 2 = age, 3 = duration of symptoms, 4 = ASA, 5 = body mass index, 6 = heart rate, 7 = white blood cells, 8 = temperature, 9 = C-reactive protein, 10 = size of appendicular mass.

Mentula et al [34], 2015 RCT

45 ± 14
46 ± 13.75

2, 3, 5

1, 2, 3, 4, 5, 7, 9, 10

St Peter et al [33], 2010 RCT

10.1 ± 4.2
8.8 ± 4.2, P = 0.31

2, 3, 4, 5

1, 3, 5, 7, 8

Aranda-Narvaez et al [32], 2010 RS

35.8 ± 12
35.4 ± 12

2, 3, 4, 5

1, 2, 3, 4, 6, 7, 8, 9

Roach et al [31], 2007 RS

1, 3, 4, 5, 6

1, 2, 7, 8

Henry et al [30], 2007 RS

8.5 - 9

1, 3, 6

1, 2, 7, 8

Erdogan et al [29], 2005 RS

1, 3, 4

1, 2, 3, 5, 7, 8

Kumar et al [28], 2004 RCT

31.6 ± 14.6
26 ± 12.4

3, 4

Ho et al [27], 2004 RS

12 - 11

1, 3, 4, 6

1, 2, 3, 5, 7, 8

Brown et al [26], 2003 RS

31 - 35

2, 4, 5

1, 2, 4, 6, 7, 8

Samuel et al [25], 2002 PS

7 - 7

1, 3, 4, 5

1, 2, 3

Tingstedt et al [24], 2002 RS

42 - 50

2, 3, 4, 5

1, 2, 3, 6, 7, 8

Oliak et al [23], 2001 RS

31 - 35

2, 3, 4, 5

1, 2, 3, 4, 6, 7, 8

Bufo et al [22], 1998 RS

10 - 11

1, 3, 4, 5, 6

1, 2, 3, 7, 8

Handa et al [21], 1997 RS

7 - 8

1, 3, 5

1, 2, 3, 7

Hume et al [20], 1995 RS

48 - 43

2, 3, 4, 5

1, 2

Gahukambe et al [19], 1993 RS

< 12

1, 3, 4

Hoffmann et al [18], 1991 RS

35 - 37

1, 2, 3, 4, 5

1, 3

Lewin et al [17], 1988 RS

2, 3, 4, 5

1, 2, 3

Gomez-Lorenzo et al [16], 1987 RS

106

39 - 53

1, 2, 3, 4

1, 2, 3, 7, 8

Foran et al [15], 1978 RS

30 - 34

2, 3, 4, 5

2, 3, 7, 8, 9

Gastrin et al [14], 1969 RS

< 15

1, 3, 4, 5

1, 2, 3

Pooled n = 1,864

810 (43%)

932 (57%)

HQ = 14

**Table 2.** Outcomes of Interest
Outcome of interest	No. of studies, no. of patients	Statistical method, estimated effect, 95% CI	P value	I² (%)
RCTs: randomized controlled trials; IV: intravenous; MD: mean difference; RE: random-effects; FE: fixed-effects; OR: odds ratio.
Duration of first hospitalization [15, 17, 23-27, 30, 34]	9, 885	MD: -0.48, 95% CI: -3.11 -2.16	0.72	98
Overall duration of hospitalization [18, 21, 24-26, 28, 31, 33, 34]	10, 605	MD: -0.48, 95% CI: -2.86 -1.89	0.69	94
Overall duration of hospitalization RCTs [28, 33, 34]	3, 140	MD: 1.48, 95% CI: -2.60 -5.57 (RE) MD: -0.94, 95% CI: -1.26 to -0.62 (FE)	0.48 < 0.001	86 86
Overall duration of hospitalization high-quality RCTs [33, 34]	2, 100	MD: -0.99, 95% CI: -1.31 to -0.67 (FE)	< 0.001	0
Duration of IV antibiotics [22, 24, 25, 27, 34]	5, 383	MD: -0.52, 95% CI: -2.42 - 1.38	0.59	94
Re-operations [14, 16, 20, 22, 34]	5, 423	Peto OR: 1.41, 95% CI: 0.64 - 3.13	0.40	81
Overall complications [14-34]	20, 1,660	Peto OR: 2.90, 95% CI: 2.31 - 3.65	< 0.001	78
Abdominal/pelvic abscesses RCTs [33, 34]	2, 100	OR: 0.46, 95% CI: 0.17 - 1.29	0.14	0
Abdominal/pelvic abscesses [14, 16, 17, 23, 26, 30, 31, 32-34]	11, 1,116	OR: 3.13, 95% CI: 1.18 - 8.30	0.02	71
Wound infections [16, 17, 19, 20, 22, 23, 26-28, 30, 32]	12, 1,094	OR: 3.95, 95% CI: 1.95 - 8.00	< 0.001	43

Table 2. Outcomes of Interest

Outcome of interest

No. of studies, no. of patients

Statistical method, estimated effect, 95% CI

P value

I² (%)

RCTs: randomized controlled trials; IV: intravenous; MD: mean difference; RE: random-effects; FE: fixed-effects; OR: odds ratio.

Duration of first hospitalization [15, 17, 23-27, 30, 34]

9, 885

MD: -0.48, 95% CI: -3.11 -2.16

0.72

Overall duration of hospitalization [18, 21, 24-26, 28, 31, 33, 34]

10, 605

MD: -0.48, 95% CI: -2.86 -1.89

0.69

Overall duration of hospitalization RCTs [28, 33, 34]

3, 140

MD: 1.48, 95% CI: -2.60 -5.57 (RE)
MD: -0.94, 95% CI: -1.26 to -0.62 (FE)

0.48
< 0.001

86
86

Overall duration of hospitalization high-quality RCTs [33, 34]

2, 100

MD: -0.99, 95% CI: -1.31 to -0.67 (FE)

< 0.001

Duration of IV antibiotics [22, 24, 25, 27, 34]

5, 383

MD: -0.52, 95% CI: -2.42 - 1.38

0.59

Re-operations [14, 16, 20, 22, 34]

5, 423

Peto OR: 1.41, 95% CI: 0.64 - 3.13

0.40

Overall complications [14-34]

20, 1,660

Peto OR: 2.90, 95% CI: 2.31 - 3.65

< 0.001

Abdominal/pelvic abscesses RCTs [33, 34]

2, 100

OR: 0.46, 95% CI: 0.17 - 1.29

0.14

Abdominal/pelvic abscesses [14, 16, 17, 23, 26, 30, 31, 32-34]

11, 1,116

OR: 3.13, 95% CI: 1.18 - 8.30

0.02

Wound infections [16, 17, 19, 20, 22, 23, 26-28, 30, 32]

12, 1,094

OR: 3.95, 95% CI: 1.95 - 8.00

< 0.001