Primary Definitive Procedure versus Conventional Three-staged Procedure for the Management of Low-type Anorectal Malformation in Females: A Randomized Controlled Trial.

INTRODUCTION: Females with Krickenbeck low-type anorectal malformations - vestibular fistula (VF) and perineal fistula (PF) - are managed either by a primary definitive or conventional three-staged approach. Ultimate outcome in these children may be affected by wound dehiscence leading to healing by fibrosis. Most of the literature favors one approach over other based on retrospective analysis of their outcomes. Whether a statistically significant difference in wound dehiscence rates between these approaches exists needed to be seen.
MATERIALS AND METHODS: A randomized controlled trial for girls <14 years with VF or PF was done. Random tables were used to randomize 33 children to Group I (primary procedure) and 31 to Group II (three-staged procedure). Statistical analysis was done for significance of difference (P < 0.05) in the primary outcome (wound dehiscence) and secondary outcomes (immediate and early postoperative complications).
RESULTS: Of the 64 children randomized, 54 (84%) had VF. Both groups were comparable in demography, clinical profile and age at surgery. The incidence of wound dehiscence (39.4% vs. 18.2%; P = 0.04), immediate postoperative complications (51.5% vs. 12.9%; P = 0.001), and early postoperative complications (42.4% vs. 12.9%; P = 0.01) was significantly higher in Group I as compared to Group II. Six of 13 children (46.2%) with dehiscence in Group I required a diverting colostomy to be made.
CONCLUSIONS: Females with VF or PF undergoing primary definitive procedure have a significantly higher incidence of wound dehiscence (P = 0.04), immediate (P = 0.001) and early postoperative complications (P = 0.01).

RCT Entities:   Population Interventions Outcomes

Introduction

During the last 15 years, significant advances have been made in the management of children with anorectal malformation (ARM). Besides anatomic reconstruction, management of the functional sequelae has become one of the main objectives in the management of these children to provide them with a good quality of life.[1] Females with Krickenbeck low-type ARM - vestibular fistula (VF) and perineal fistula (PF) are managed either by a primary definitive or conventional three-staged approach.[2] Most of the literature favors one approach over other based on retrospective analysis of their outcomes. Repair without a protective colostomy avoids the potential morbidity of a colostomy and reduces the number of operations to one rather than three (colostomy, definitive repair and colostomy closure). However, this exposes the child to increased risk of wound dehiscence and therefore to a greater risk of damage to the sphincteric mechanism owing to severe fibrosis. A covering colostomy is still the safest way to avoid these complications. Whether the above statements stand for a fact or are just observational bias needed further exploration. Hence, a prospective randomized controlled trial was conducted between cases undergoing primary definitive procedure and those managed with a three-staged approach and outcomes evaluated.

Materials and Methods

A prospective randomized controlled trial was carried out at a single tertiary care institute over a period of 3 years (June 2012 - June 2015). All females <14 years age with low-type ARM according to the Krickenbeck classification – VF and PF, presenting during this period were included in the study. Any previously attempted definitive surgery for the ARM, local perineal abnormality that precluded the performance of the primary definitive procedure or refused parental consent to participate entailed exclusion from the trial. Randomization was done using random permuted blocks. Patients were randomized into Group I (primary definitive procedure) and Group II (three-staged procedure-colostomy, definitive procedure and colostomy closure). Ethical clearance was obtained from the Institute's Ethics Committee and fully informed parental consent was obtained for every patient.

Children randomized for the three-staged repair (Group II) underwent a high sigmoid loop colostomy using the standard surgical technique. Children randomized to Group I underwent primary definitive correction. At the time of definitive procedure, bowel preparation in Group I was done using rectal washouts for a week and total gut irrigation (TGI) (either with polyethylene glycol or normal saline) 24 h before surgery. In Group II, distal stomal washes and rectal washouts were given for 48 h before definitive surgery.

All the definitive procedures were performed by either of 3 surgeons with more than 15 years of experience in the field. Choice of definitive procedure was left to the surgeon's preference, which included either mini-posterior sagittal anorectoplasty (PSARP), PSARP or anterior sagittal anorectoplasty (ASARP). Rectal packing for 24 h, urethral catheter drainage for 5 days nil orally for 5 days, broad spectrum antibiotics for 7 days, and standard wound care were employed in all cases. Standard wound care included local wound cleaning and antibiotic ointment (polymyxin B + bacitracin + neomycin) application for 2 weeks. Sitz bath and warm compresses were added in children with wound infection. In case of major wound dehiscence (deep or circumferential), a diverting colostomy was constructed in cases of failure of conservative local measures.

Primary outcome measure was perineal wound dehiscence. Wound dehiscence was defined as disruption of skin sutures (superficial) or deeper muscle layer (deep) of perineal wound of definitive surgery. Secondary outcome measures included any immediate (0–7 days) postoperative complications such as fever, bleeding, wound erythema or pus discharge and early (8 days–1 month) postoperative complication such as mucosal prolapse, stenosis, recurrence or retraction.

Statistical analysis was done using software Stata® version 12.1 (StataCorp LP, Texas, USA). Data were presented as number (%) or mean ± standard deviation (range) as appropriate.

Results

A total of 64 females were randomized into two groups - 33 patients in Group I (primary definitive procedure) and 31 patients in Group II (three-staged procedure). Two females primarily randomized to Group I underwent a three-staged procedure due to various reasons. However, as an intention to treat analysis was followed, these were included in Group I for all statistical analyses.

Baseline characteristics

Both groups were comparable in terms of baseline characteristics such as age at presentation, age at surgery, type of anomaly (VF or PF), symptoms at presentation, and procedures performed. The median age at presentation was 14.8 ± 3.2 months (range 0–96 m) in Group I and 21.3 ± 6.9 months (range 0–149 m) in Group II [Figure 1]. This difference was not statistically significant (P = 0.272). The median age at definitive surgery was 15 ± 3.2 months (range 0–96 m) in Group I and 25.7 ± 6.9 (range 3–156 m) in Group II. This difference was also not statistically significant (P = 0.213). There were 25 (75.8%) VF and 8 (24.2%) PF in Group I and 29 (93.6%) VF and 2 (6.4%) PF in Group II. This difference was not statistically significant (P = 0.176). At presentation, 19 of the 33 patients (57.6%) in Group I and 19 of 31 (61.3%) in Group II were symptomatic, having either straining during defecation, constipation or a combination thereof. This difference in clinical presentation was not statistically significant (P = 0.762). Abdominal palpation revealed fecalomas in 9 of 33 (27.27%) in Group I and 8 of 31 (25.81%) in Group II. Both groups were comparable in terms of the presence of fecalomas (P = 0.894). The incidence of associated anomalies of the other systems for the entire cohort was 26.56% [Figure 2]. The incidence of associated anomalies of the other systems was 7 of 33 (21.21%) and 21 of 31 (67.74%) in Groups I and II respectively, and this difference was also not statistically significant (P = 0.416).

Figure 1

Age distribution at presentation

Figure 2

Associated anomalies. *Multisystem: when more than two systems involved

Minor colostomy complications were noted in 9 out of 31 children in Group II (29.03%). These were peristomal excoriation (6), bleeding (1), diarrhea (1) and obstruction (1). None had prolapsed or needed to be revised.

Definitive procedure

Among the 33 in Group I, 16, 15 and 2 underwent PSARP, mini-PSARP and ASARP respectively, while among the 31 in Group II, 17, 12 and 2 underwent PSARP, mini-PSARP and ASARP respectively. The definitive procedures employed in both the groups for various type of anomalies were not significantly different (P = 0.86).

Primary outcome

Wound dehiscence (superficial and deep) occurred in 13 of 33 (39.4%) children in Group I and in 6 of 31 (18.2%) children in Group II. This difference was significant (P = 0.038). On logistic regression analysis, the odds ratio of wound dehiscence associated with a staged procedure was 0.55 (95% confidence interval = 0.31–0.98; P = 0.042). Therefore, a staged procedure was associated with 45% less odds of dehiscence as compared to a primary definitive procedure. Dehiscence occurred after a mean 4.1 days (range 2–15 d) postoperatively in Group I and 3.6 days (range 3–4 d) in Group II (P = 0.76). Out of 13 children with wound dehiscence in Group I, 6 (46.2%) had superficial whereas 7 (53.8%) had deep dehiscence. In Group II, 4 of 6 (66.7%) had superficial and 2 (33.3%) had deep wound dehiscence. There was no significant difference in the severity of dehiscence among the two groups (P = 0.405). For the entire cohort of patients, the incidence of dehiscence in children with VF (16/54; 29.6%) was comparable to those with PF (3/10; 30%) (P = 0.98). Although a higher mean age was noted in children who had wound dehiscence (29.4 ± 41.9 months) as compared to those who did not (16.3 ± 23.3 months), this difference was not statistically significant (P = 0.115).

Of the 13 children in Group I who had a dehiscence, 6 (46.2%) had a fecaloma, while of the 6 children with dehiscence in Group II, only 1 (16.6%) had a fecaloma preoperatively. Intraoperative wound contamination with stool occurred in 6 out of 33 children (18.2%) in Group I and 1 of 31 (3.2%) in Group II (P = 0.055). Out of these 7, 6 (85.7%) had wound dehiscence (5 in Group I and 1 in Group II). This was significantly higher (P = 0.001) than those who did not have contamination (22.8%). Out of 33 Group I children, 14 (42.4%) passed stools <48 h postoperatively out of whom 7 (7/14, 50%) developed wound dehiscence. On the other hand, 6 of the 19 children who passed stools after 48 h had wound dehiscence (31.6%).

Secondary outcomes

The incidence of immediate postoperative complications among children of Group I (17/33; 51.5%) was significantly higher (P = 0.001) than Group II (4/31; 12.9%) [Table 1]. The incidence of early postoperative complications in Group I (14/33; 42.4%) was also significantly higher (P = 0.01) as compared to Group II (4/31; 12.9%) [Table 2].

Table 1

Immediate complications (0-7 days)

Table 2

Early complications (8-30 days)

Management of wound dehiscence

Out of 13 children who had dehiscence in Group I, 5 (38.5%) were managed conservatively with local wound care, 1 (7.7%) required secondary suturing, 6 (46.2%) required a diverting colostomy with either secondary suturing of the local wound immediately (n = 3) or redo definitive procedure at a later date (n = 3). One (7.7%) child, initially managed conservatively, developed a recurrent fistula and underwent redo PSARP later. This was done without a colostomy cover. Out of 6 children who had dehiscence in Group II, 3 (50%) were managed conservatively with local wound care, 2 (33.3%) required secondary suturing and 1 (16.7%) child underwent redo PSARP later because of retraction of mucosa.

Discussion

Surgeons have used both single stage and 3-staged strategies for management. Although a primary definitive procedure involves single surgery but has its risk of wound dehiscence and eventual fibrosis and sphincter damage. An incidence of perineal wound infection up to 53.1% after primary PSARP for ARM has been reported in literature. Once the sphincter mechanism is jeopardized, suboptimal results in terms of long-term continence may ensue. Wakhlu et al., in their series of 1206 females with low-type ARM treated by ASARP route, reported on outcomes in those undergoing a single-stage procedure (n = 1169).[3] Preoperative bowel preparation was done in all children. Washing of wound after passage of stools followed by povidone-iodine ointment application was done. Overall, complication rate was 5%. Postoperative wound disruption occurred in 8 (0.68%) and required colostomy in 4 (0.34%). Four patients (0.34%) had recurrence of VF which required redo definitive procedure in three and diversion colostomy followed by redo definitive procedure in the fourth child. In the present study, wound dehiscence (superficial and deep) rate of 39.4% was noted in the single-stage group whereas it was significantly lower (P = 0.038) in the staged group (18.2%). Another study by Menon and Rao assessed the feasibility of the primary definitive procedure in VF in 72 females.[4] None of them had wound dehiscence, and only 5 had minor wound infection that was managed conservatively. However, they excluded children with dilated rectosigmoid (on contrast enema) and presence of fecalomas from undergoing a single-stage procedure. In the present study, such exclusion was not performed. The presence of dilated bowel and/or fecalomas may have been one of the risk factors for wound dehiscence in the present study, which is taken care of with diversion in the three-staged group. Peña[5] and Heinen[6] felt the need for colostomy in females with low-type ARM. They asserted that satisfactory results can be achieved in these children up to 90%–95% times and any major complication would mean 3 additional operations, i.e. colostomy, redo repair and colostomy closure. In spite of this, same results cannot be achieved in subsequent redo surgery. In addition, the amount of dissection in these cases is almost the same as that of high lesions thereby justifying the need for a protective colostomy. Out of 35 females with VF evaluated by Wilkins and Peña, 10 had a mismanaged primary definitive procedure resulting in wound dehiscence in all of them.[7] Their re-repair after a diverting colostomy and the remaining 25 repairs under cover of a colostomy were successful. They thus strongly emphasized the importance of colostomy in these children.

The incidence of colostomy-related complications has been reported in literature from 28% to 74%.[89] In the present study, minor colostomy complications were noted in 9 out of 31 Group II children (29.03%). Peña et al. attribute the high colostomy complication rate to faulty technique and management of the stoma.[10] They reported their stoma complication rate as 8% and asserted that the high stoma-related complication rate should not be taken as a supportive argument for doing a primary definitive procedure. In the present study, however, stomal complications reported are mainly related to the improper management of stoma by parents at home and lack of affordability for stoma bags.

A major issue in our patient population, like in many other developing countries, is the delayed presentation of these children. In case of late presenters, bowel may be dilated and partially adynamic. In such cases, even after definitive surgery, the dilated rectum does not recover its normal peristalsis.[10] In a series of 14 cases of low ARM published by Haider and Fisher, there were 4 such cases (28.6%) that required a defunctioning colostomy to allow decompression and recovery of the rectum before delayed reconstruction up to 3–6 months later.[11] In the present study, an older mean age was noted in children who had wound dehiscence (29.4 ± 41.9 months) as compared to children who did not (16.3 ± 23.3 months) although this difference did not reach statistical significance (P = 0.115).

Menon and Rao, in their series of 72 females with low ARM who underwent primary PSARP, emphasized the importance of TGI and avoidance of fecal contamination of wound to achieve successful results (minor wound infection in 5, wound dehiscence in none).[4] In the present study, thorough bowel preparation (including TGI) was administered to all. Among the entire cohort, 6 of 7 children (85.7%) with intraoperative fecal contamination had wound dehiscence which was significantly higher than those who did not have fecal contamination (22.8%) (P = 0.001). It may be recommended based on above findings that in case fecal contamination occurs during the primary definitive repair, it will be prudent to do a diversion at the same time rather than risking the wound for dehiscence.

Immediate complications including fever, pus discharge, erythema and bleeding occurred in children of both groups. Their incidence was significantly higher (P = 0.001) in Group I (51.5%) as compared to Group II (12.9%). Similarly, early complications including mucosal prolapse, retraction, neonatal stenosis and recurrence of fistula were significantly higher (P = 0.01) in Group I (42.4%) as compared to Group II (12.9%).

The ultimate outcome in these females with low-type ARM may be affected by wound dehiscence and infection leading to healing by fibrosis and scarring. Whether these complications have any significance in the long-term outcomes still needs to be studied by their linear follow-up.

Conclusions

Females with low-type ARM treated with primary definitive procedure have a significantly higher incidence of wound dehiscence, immediate and early postoperative complications. Intraoperative fecal contamination of the surgical site significantly increased the incidence of wound dehiscence.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.