Kore S, Vyavaharkar M, Akolekar R, Toke A, Ambiye V

Department of Obstetrics and Gynaecology, L. T. M. G. Hospital, Sion, Mumbai - 400 022, India
Address for correspondence: Dr. Shailesh Kore, Department of Obstetrics and Gynaecology, L. T. M. G. Hospital, Sion, Mumbai 400 022, India.

Code Number: jp00007

Abstract:

Aims: To evaluate the role of subcutaneous tissue closure in relation to wound disruption after abdomibal hysterectomy in obese patients. Material and Methods: In a prospective study at a tertiary referal centre in Mumbai, India, 60 obese patients with subcutaneous fat more than 2.5 cms were included in the study. In 30 patients, subcutaneous tissue was closed using synthetic suture (dexon) while in 30 control patients subcutaneous tissue was not closed. Average weight in the study and control groups were 69 kg and 63.3 kg respectively. Results: The wound disruption occurred in 5 patients in non-closure group as compared to only one in the closure group. Incidence of seroma, haematoma formation and other wound complications were higher in the non-closure group. CONLUSIONS: Closure of the subcutaneous tissue after abdominal hysterectomy of women with at least 2.5 cms of subcutaneous tissue lowers the overall rate of complications leading to disruption of the incision. (J Postgrad Med 2000; 46:26-28)

Key Words: Subcutaneous tissue, Wound Disruption, Obesity.

Disruption of the abdominal incision is a major source of morbidity after abdominal hysterectomy. Infection, haematoma or seroma formation can disrupt skin closure or necessitate opening the incision for drainage. Infection is the most common cause of wound disruption. The incidence of post-operative wound infection, though changes with population studied ranges between 2.5% to 29.7%. It is important to identify risk factors and treatment modalities that can decrease the incidence of these complications.

Obesity has been identified as strong independent risk factor for wound complications. The vascular supply to the subcutaneous fat is relatively poor, making this tissue susceptible to infection after contamination with pathogens. Serous fluid collection and haematoma collection even increase the risk of infection. Although closure of subcutaneous fat may decrease serous fluid collection, additional suture material may increase the risk of wound infection. The purpose of this study was to determine whether the closure of subcutaneous tissue in obese women decreases the rate of wound disruption without increasing the rate of wound infection.

Material and Methods

A prospective study comparing closure with non-closure of the subcutaneous tissue after abdominal hysterectomy was done at a large general hospital, Sion, Mumbai, over a period of two years. Only patients for abdominal hysterectomy for benign gynaecological conditions were included in the study. A total of sixty cases were included in the study, thirty in each group. All patients with at least 2.5 cms (one inch) of subcutaneous fat, found at time of surgery, were eligible for the study. The cases were distributed randomly so as to keep number of patients comparable in two groups as related to indication of abdominal hysterectomy, type of incision, medical complication, socio-economic status, pre-operative and intra-operative high risk factors.

After fascia closure, the subcutaneous tissue thickness was measured with sterile metallic ruler in middle of the incision, from skin surface to fascia. In Pfannensteil incision, the depth of subcutaneous fat was measured at the cephalic end. The wound was irrigated with sterile saline. In closure group, subcutaneous tissue was sutured with continuous running suture using 2-0 polyglycolic acid (dexon). The skin was sutured by black silk with vertical mattress sutures. The incision was dressed with sterile bandage that was removed on the fifth post-operative day and the new dressing was done. The sutures were removed on seventh post-operative day in patients without any complications. All patients received post-operative antibiotics (cephalosporins and metronidazole) for seven days.

Results

Majority of our patients were between 40-50 years of age. Table 1 summarises demographic information for two groups. Average depth of subcutaneous fat was 3-6 cms, while average weight was 66.5 kg in these patients. There were a total of three patients of diabetes mellitus taking insulin therapy in this study.

A majority of these patients were from lower middle class. The indications for abdominal hysterectomy are listed in Table 2. In 15 patients of closure group and 13 patients of non-closure group, midline vertical incision was used while pfannenstiel incision was taken in remaining patients.

Table 3 compares post-operative condition and results in these two groups. Incidence of post-operative fever (temperature more than 38 degree after first 24 hours lasting for at least 24 hours) was 10%.

An infection of wound, as diagnosed by purulent discharge with classical signs of erythema, induration and tenderness was found in two cases of closure group as compared to four cases in non-closure group. A wound draining sero-sanguinous fluid and not meeting criteria for infection was classified as having seroma. It was found in total five cases, one in closure and four in non-closure group.

All patients with infection were treated with higher antibiotics with or without drainage of pus by opening the wound.

The disruption of wound was observed in six cases. The superficial disruption of wound (meaning less than one cms deep disruption) was managed conservatively, while more than one cm thick gaping was of deep type and required secondary suturing. One patient in closure group and three in non-closure group, had a complete gaping of wound comprising full length and full thickness till rectus sheath. It also included one case of wound dehiscence in non-closure group. The incidence of overall complications was higher in control group and in patients with diabetes, previous scar or per-operative infection.

Discussion

Wound complications after abdominal hysterectomy are a major cause of morbidity and increased length of hospital stay. These complications can occur despite strict adherence to good surgical technique. Although, careful handling of tissue to minimise trauma, minimal use of cautery, observance of aseptic technique, adequate skin preparation and the use of prophylactic antibiotics are important in preventing wound complications. The additions of subcutaneous suture can further reduce wound disruption in women with at least 2.5 cms of subcutaneous fat.

The most important factor of subcutaneous closure appears to result from a reduction in the incidence of seroma formation. When the abdominal incision is closed by re-approximating only the fascia and skin, a potential space is left in the subcutaneous tissue. This dead space can serve as a reservoir for the collection of serous fluid or blood, increasing the possibility of seroma or haematoma. These pockets of fluid can easily get infected during surgery or in the post-operative period. Also, mechanical stress on the skin incision is increased when the subcutaneous tissues are not closed making disruption of the wound incision more likely. Del valle et al published a randomised study comparing closure of subcutaneous tissue with no closure during caesarean delivery and demonstrated a reduction of the post-operative wound disruption from dead space obliteration ¹ .

Although, subcutaneous closure prevent seroma formation and reduce the tension on skin incision, these sutures can cause necrosis and invite infection. Elek and Conen reported that the presence of suture material can decrease the inoculum of bacteria needed to cause infection by factor 10,000 ² . But most of the studies have not consistently shown any significant increase in infection rate in closure group. The type of suture material and technique of closure is important in this respect. Synthetic absorbable suture (dexon) was chosen because it has been demonstrated to be less inflammatory in human than gut suture ³ .

A horizontal running suture was used to distribute the tension evenly throughout the length and to lessen the possibility of tissue necrosis.

This study demonstrates that closure of the subcutaneous tissue after abdominal hysterectomy of woman with at least 2.5 cms of subcutaneous tissue lowers the overall rate of complications leading to disruption of the incision.

Thus, closure of subcutaneous tissue is desirable and should be done following abdominal hysterectomy in obese patients who are at high risk for wound complications.

Acknowledgement

We thank our Dean and Head of Department for allowing us to use and publish the hospital data.

References