Incidence Rates and Predictors of Stomal-Related Complications: A 1-Year Prospective Study

Stomal-related complications (SRCs) increase health care expenditures, outpatient visit and hospital readmission rates, length of stay, and community care requirements while reducing quality of life.^1,2 SRCs are classified as stomal complications (SCs) and peristomal complications (PCs). Prolapse, necrosis, mucocutaneous separation, stoma retraction, stenosis, fistula, and stomal trauma are examples of SCs; parastomal hernia, varices, candidiasis, folliculitis, mucosal transplantation, pseudoverrucous lesions, pyoderma gangrenosum, suture granuloma, irritant contact dermatitis, allergic contact dermatitis, and peristomal trauma are categorized as PCs.³

A systematic review including 11 studies reported that the rates of SRCs range from 10% to 60% in patients with stomas.⁴ This variation can be attributed to the different types of SRCs and observational time points. A prospective study of 180 patients with stomas by Persson et al⁵ revealed that most complications occur 2 weeks after discharge for ostomy and that 53% to 79% of patients had 1 or 2 SRCs, depending on the type of stoma. The most common postoperative complication at ward review was stomal necrosis, which was observed in 20% of patients who underwent colostomy.⁵ This study also reported that peristomal skin problems were the most common SRCs observed in patients with ileostomies who had been followed for 2 years.⁵ Another prospective study of 192 patients who had enterostomies showed a 27.1% incidence rate of SRCs within 6 months after the surgery; stoma retraction and mucocutaneous separation were the most frequently observed.²

A secondary data analysis reported a 47.7% incidence of PCs and that commonly observed PCs were peristomal moisture–associated skin damage (PMASD) and mechanical trauma. After an average hospital stay of 23 days, the PCs of 39.7% of the patients resolved.⁶ Further studies are warranted to identify risk factors for different types of SRCs and to determine the underlying reasons for the low rate of PC resolution and the long time required for their resolution. For this purpose, heterogeneity in study quality, inclusion criteria, SRC type, and statistical methods used should be considered.

A prospective study including 192 patients with stomas reported that early SCs were related to stoma type of colostomies, short stoma length, high body mass index (BMI), emergency surgery, and no stoma marking before surgery.² Moreover, a retrospective study including 214 patients who did not have stoma site marking before surgery showed that a BMI of >25 kg/m² was related to PCs.⁷ Pilgrim et al reported a relationship between a BMI >35 kg/m² and parastomal hernia.⁸

Regarding the relationship between stomal configuration and SRCs, a study of 180 patients receiving elective enterostomy reported that a low stomal height (ileostomy with a height lower than 20 mm, and colostomy height lower than 5 mm) was related to leakage from the base of the stoma and peristomal irritant contact dermatitis.⁵ Furthermore, Lindholm et al reported that the incidence rate of parastomal skin problems was between 21% and 57% and related to a narrow or low stoma.⁹ Therefore, stomal size is a crucial factor influencing the incidence of SRCs.¹⁰

The purpose of the current prospective study was to investigate the incidence rates of both SCs and PCs at 30, 90, 180, and 360 days after ostomy and to determine the risk factors for SRCs.

Study design and procedures. This was a 1-year prospective study of patients undergoing ostomy in a medical center in eastern Taiwan from January 2014 through December 2016. Patients aged older than years and undergoing ostomy were recruited; patients with stoma created for nutritional feeding rather than for defecation were excluded.

After patient enrollment, the wound, ostomy, and continence nurses (WOCNs) explained the aim and methods of this study to the patients and their family members. All patients provided written informed consent before participation, and the study was approved by an institutional review board (Research Ethics Committee No.: IRB102-131). All patients were followed up by WOCNs at 5 time points spread over 1 year (3, 30, 90, 180, and 360 days after the surgery) in the hospital or outpatient clinic. The WOCNs reminded the patients of their appointments 14 days beforehand; the follow-ups could occur within 5 days before or after the targets. Baseline data were collected at the first time point, and SRCs were assessed at every following time point by a physician, a colorectal surgeon, and 2 WOCNs.

Measurement of variables and endpoints. In this study, participants were asked to complete a questionnaire with reference to related articles. The questionnaire included items on 1) demographics, including age, sex, marital status, occupation, and education; 2) the baseline characteristics of the patients, including weight, height, BMI, self-care status (ability to care for oneself or rquiring assistance from a caregiver), elective or emergency surgery, and surgical approach (open or laparoscopic); and 3) the baseline characteristics of the stoma, including diversion type (colostomy, ileostomy, or urostomy), stomal construction (single end, loop, or double barrel), stomal diameter, and stomal height.

In this study, the appropriate stomal location was considered to be within the rectus abdominis muscle and not within large/protruding/pendulous abdomen, abdominal folds, wrinkles, pendulous breasts, scars/suture lines, other stomas, waistline, or iliac crest or in the presence of a hernia. A digital Vernier caliper LCD micrometer was used to measure the diameter and height of the stoma. An abnormal diameter was defined as a stoma with a difference of > 3 mm between the major and minor axes. Stomal heights of < 5 mm and < 20 mm for colostomy and ileostomy, respectively, were considered low stomas.

The current study referenced the work of Beitz and Colwell to define SRC endpoints and grouped SRCs as SCs or PCs.³ SCs included stoma retraction, prolapse, ischemia/necrosis, mucocutaneous separation, and bleeding. PCs included PMASD, parastomal hernia, allergic contact dermatitis, abscess, and pyoderma gangrenosum. A physician and 2 WOCNs examined all SRCs, and all stoma sites were photographed.

Patient confidentiality. The patients were interviewed individually, and their medical data were decoded and unlinked with personal data. The data were analyzed by an independent researcher and saved encoded.

Data management. The incidence rate of SRCs was defined as the rate at which new cases of SRCs occurred during a certain observational period and was calculated using the following formula: incidence rate = (number of new SRCs / number of observations in the period) × 100. BMI was calculated as weight (kg) / height (m²). In the survival analysis, the numbers of SRC events at 5 time points were counted.

Data analysis. Continuous data were presented as means and standard deviations, and categorical data were presented as numbers and percentages. Percentages were calculated for overall SRCs and individual complications as well as for SCs and PCs. The incidence rate of SRCs (number/person-days) was calculated as the number of SRCs case per person-time. Survival and cumulative incidence rates of enterostomy complications were calculated by survival analysis. Logistic regression was used to estimate the odds ratio (OR) for incident SRCs. Means were compared through analysis of variance. A 2-sided P value < .05 was considered statistically significant. All statistical analyses were performed using SAS software, version 9.3 (SAS Institute Inc.).

Of the 215 patients included in this study, 215, 174, 136, 74, and 50 patients were followed at 3, 30, 90, 180, and 360 days, respectively. The mean patient age was 62.5 years, and 29.3% of patients were men; 42 (19.5%) were capable of self-care, whereas 173 (80.5%) received care from a caregiver. Of the 215 patients enrolled, 109 (50.7%) and 32 (14.9%) had colorectal cancer and pressure injury, respectively. Eighty-six (86) patients (40%) required emergency surgery, and the remainder (n = 129) underwent elective procedures. Open surgery was performed on 126 patients (58.6%), and 89 (41.4%) underwent laparoscopic surgery. Colostomy, ileostomy, and urostomy were performed in 148 (68.8%), 59 (27.4%), and 8 (3.7%) patients, respectively. Loop stomas were created in the majority of patients (n = 148; 68.8%); single-end stomas were created in 66 patients (30.7%), and a double-barrel stoma was created in 1 patient (0.5%).

The assessment of stoma location by WOCNs revealed that 112 stomas (52.1%) were created at inappropriate locations, and 25 stomas (11.6%) had diameters that varied >3 mm between the major and minor axes. In total, 112 patients (52.1%) had a stomal height considered to be low for its type. The characteristics of patients with and without SRCs are presented in Table 1, Part 1; Part 2, and Part 3; significant differences were observed in stoma location (P < .001) and diameter (P < .001).

In total, 98 patients (46%) experienced complications by 90 days postoperatively. The survival curves indicated that 27% to 86% of patients were free from SRCs from day 3 to 360 (Figure 1). The cumulative incidence rate of SRCs was 73% at 360 days.

The 145 SRCs (Table 2) were composed of 66 SCs (45.5%) (Table 3) and 79 PCs (54.5%) (Table 4). Among the SCs, 17.9%, 9.0%, 6.9%, 6.9%, and 4.8% were stomal retraction, stomal prolapse, stomal ischemia/necrosis, mucocutaneous separation, and bleeding, respectively. Among the PCs, 46.9%, 2.8%, 2.1%, 2.1%, and 0.7% were PMASD, parastomal hernia, peristomal allergic contact dermatitis, peristomal abscess, and peristomal pyoderma gangrenosum, respectively. The highest incidence of PCs was observed 30 days after the surgery (26.4%; Table 4). The trends of the incidence rates of SCs and PCs are shown in Figure 2. Figure 3 shows that, at 3 days after surgery, stomal ischemia/necrosis and mucocutaneous separation accounted for 25% of the overall SRCs, and PMASD accounted for 17.5%. However, PMASD accounted for 59.4% and 58.6% of SRCs at 30 and 90 days after surgery, respectively; at 180 days after surgery, stoma retraction was the most common SRC, accounting for 50% of the total.

Table 5 shows the predictors of SCs and PCs based on logistic regression. Emergency surgery for stoma creation was associated with an increased OR for SCs (OR = 2.78; P = .041). Laparoscopic surgery (OR = 2.91; P = .023), and inappropriate stoma location (OR = 19.23; P < .001) were similarly associated with increased risk for SCs.

Of the 215 patients in this prospective cohort study, approximately 86%, 77%, 63%, 54%, and 27% were free from SRCs at 3, 30, 90, 180, and 360 days after surgery, respectively. The incidence of inappropriate stoma location and abnormal stomal diameter significantly differed between patients with and without SRCs. The 145 SRCs comprised 66 (45.5%) SCs and 79 (54.5%) PCs. The highest incidence of SCs (13.5%) was observed 3 days after surgery; PCs (26.4%) were more commonly reported 30 days after surgery. Emergency surgery, laparoscopic surgery, and inappropriate stoma location were associated with a higher incidence of SCs. PCs were mainly associated with inappropriate stoma location.

In the present study, the cumulative incidence rate was 73% for patients who underwent stomal surgery and developed SRCs at 360-day follow-up. However, previous studies have reported that at least 50% of patients who undergo stomal surgery develop SRCs.⁵ These differences may be attributed to the fact that 1 patient may have more than 1 SRC. A meta-analysis showed that the incidence of SRCs ranges from 12% to 72%, owing to the different definitions of SRCs among studies.⁴

SRCs are divided into SCs and PCs.³ In this study, the incidence rates of these 2 categories of complications were determined. The highest incidence of SCs, 13.5%, was observed at 3 days after surgery; this decreased to 5.4% thereafter. Moreover, the most commonly observed SCs were stoma retraction, prolapse, ischemia/necrosis, mucocutaneous separation, and bleeding. Stoma retraction and prolapse were commonly observed at the 360-day follow-up, a finding that is consistent with that of Salvadalena et al.¹¹

In the present study, emergency surgery (OR = 2.78; P = .041), laparoscopic surgery (OR = 2.91; P = .023), and inappropriate stoma location (OR = 19.23; P < .001) were significant predictors of SCs. A previous study of patients who underwent emergency abdominal surgery with stoma creation found a 40.2% incidence of SRCs in the ward and 54.4% incidence at a 1-year follow-up.⁹ Compared with patients who underwent elective surgery, those who underwent emergency surgery had a significantly higher rate of stoma retraction (13.6% in elective surgery and 18.6% in emergency surgery) 10 days after surgery, but no significant difference was observed at 2 years postoperatively.¹²

The highest incidence rate of PCs was 20.4% at 30 days after the surgery. PMASD was the most common PC. A prospective study of patients who underwent stomal surgery reported a 60% and 73 incidence of stoma-related skin problems after end ileostomies and loop ileostomies, respectively.⁵ PCs are long-term problems related to the duration a patient has lived with a stoma and include peristomal skin folds and creases.⁸ PC severity is associated with the type of stoma and duration of time since its creation.⁶

Inappropriate stomal location was significantly associated with SRCs (OR = 19.23, P < .001 for SCs; OR = 7.70, P < .001 for PCs). Preoperative stoma site marking was suggested for patients undergoing colostomy or ileostomy,⁶ and a separate meta-analysis reported that preoperative non marking of the stoma site was related to SCs.¹³ Stoma site marking was not examined in the present study because it is not a routine procedure before stomal surgery in the study hospital, and stoma site marking might not be possible in patients who require emergency abdominal surgery or those who are in poor condition. Therefore, patients undergoing emergency surgery should be closely monitored for SRCs, and appropriate interventions should be implemented for prevention or treatment.

This study has some limitations. Preoperative marking of the stoma site was not evaluated in this study. Because of the 1-year follow-up period, long-term SRC outcomes could not be determined. This study was conducted in a hospital in eastern Taiwan, and the results are representative of that area. A transnational study should be performed to compare these results with those of studies conducted in different countries to increase the generalizability of the findings.

The data on potential risk factors for SRCs were collected at baseline. However, BMI, stomal diameter, and stomal height change over time. More research is warranted to study temporal variations in the risk factors for SRCs. The ability of patients with SRCs to care for themselves provides a measure of the extent of complications. Such factors as muscle power, skeletal muscle comorbidities, and self-care ability should be investigated to obtain more information that could be applied for clinical care and research.

This prospective study reports a cumulative incidence rate of 73% in patients with SRCs at 1 year after stomal surgery. Stoma retraction and prolapse were common SCs related to emergency surgery, laparoscopy surgery, and inappropriate stoma location; of these, PMASD was the most frequently observed PC related to inappropriate stoma location. The ranges of incidence rates of SRCs were from 0.7% to 46.9% attributable to the complication types. Therefore, clinicians and patients must be aware that the severity and extent of SRCs depend on the duration for which the patients are followed after ostomy.

Funding was received from Hualien Tzuchi Chi Hospital, Buddhist Tzu Chi Medical Foundation (No. TCRD103-63)

Ms M-Y Hsu and Ms H-H Hsu are wound, ostomy, and continence nurses, Hualien Tzuchi Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan, Republic of China. Dr Wu is an assistant professor and a wound, ostomy, and continence nurse, St Mary’s Journal College of Medicine, Nursing and Management, Taiwan, Republic of China.

Address all correspondence to: Yu-Lin Wu, PhD, RN, WCET, St. Mary’s Journal College of Medicine, Nursing and Management, No. 100, Ln. 265, Sec. 2, Sanxing Rd., Sanxing Township, Yilan County 266, Taiwan (R.O.C.); tel: 886-3- 9603060; email: w910230@gmail.com.