Postoperative Complications of Colectomy in Diabetes Patients

Research Article

Austin J Surg. 2017; 4(4): 1111.

Postoperative Complications of Colectomy in Diabetes Patients

Ramsey T, Giaccio SL and Navarro FA*

Department of General Surgery, University of South Carolina School of Medicine, USA

*Corresponding author: Fernando A. Navarro, Department of Surgery, Two Medical Park, Suite 306, University of South Carolina School of Medicine, Columbia, SC, 29203, USA

Received: November 20, 2017; Accepted: December 13, 2017; Published: December 20, 2017


Background: In this study, we sought to determine whether Insulin Dependent Diabetes (IDDM) and Non-Insulin Dependent Diabetes (NIDDM) have different risks in comparison to non-diabetics during perioperative period of colectomy using a large national-level database.

Study Design: In our study, de-identified patients who underwent colectomy from 2012 to 2015 were selected from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) using the following CPT codes: 44140, 44141,44143, 44144, 44145, 44146, 44147, 44150, 44151, 44155, 44156, 44157, 44158, 44160, 44204, 44205, 44206, 44207, 44208, 44210, 44211, and 44212. Descriptive analysis is used to compare postoperative complication rates in each diabetes group.

Results: IDDM increased the risk of postoperative infection across all studied parameters compared to non-DM. Superficial incision SSI, deep incision SSI, and wound disruption were significantly higher in IDDM compared to non-diabetics (OR 1.39 (1.28, 1.5), 1.36 (1.16, 1.60), and 1.48 (1.27, 1.73)) respectively. IDDM was 1.85 times (1.69, 2.03) more likely to develop pneumonia and 1.66 (1.49, 1.85) times more likely to develop UTI than non-DM. Sepsis, reoperation, and readmission were also higher in IDDM patients compared to the control with an odds ratio of 1.27 (1.17, 1.38), 1.36 (1.26, 1.48), 1.52 (1.42, 1.62) respectively. NIDDM had a smaller increase in risks of superficial incision SSI, pneumonia, UTI, and readmission; however, these risks were not as high as in IDDM.

Conclusion: Clinicians should inform DM patients about their risks with colectomy and encourage them to control their DM, especially to become independent on insulin injection, to avoid these potential perioperative complications.

Keywords: Diabetes; Colectomy; Colorectal surgery; Insulin dependent diabetes; Non-insulin dependent diabetes; Perioperative complications; Perioperative infection; Surgical site infection


Non-DM: without Diabetes; IDDM: Insulin Dependent Diabetes; NIDDM: Non-Insulin Dependent Diabetes; SSI: Surgical Site Infection; UTI: Urinary Tract Infection


A careful preoperative evaluation for surgical procedures is the first step in optimizing surgical outcomes, including gathering patients’ history and performing physical examination. A risks, benefits, and alternatives analysis is carried out and conveyed to patients so they can make the most informed decision of whether to proceed with the surgery. Therefore, understanding the preoperative risks is extremely important not only in the informed decision making process but also to monitor potential complications.

Diabetes, impacting 9.3% of the population in the United States, is one of the most common preoperative risk factors for poor surgical outcomes [1]. It impacts multiple organ systems in the body causing gastro paresis, chronic kidney disease, myocardial infarct, retinopathy, and limp amputation. Stress during surgery and general anesthesia causes release of stress-related hormones and inflammatory cytokines, which in turn induce hyperglycemic state by altering insulin regulation, and protein and lipid catabolism [2]. Thus, preexisting diabetes may pose a higher risk of preoperative complications compared to healthy individuals. Multiple studies report a high incidence of preoperative infections associated with poor glycemic control [3-5]. Therefore, preoperative laboratory studies and preoperative glucose control have been carefully evaluated to avoid marked blood sugar, and fluid and electrolyte imbalance.

Tsang S et al. [6] found that the Diabetes Mellitus (DM) was associated with an increased risk of Surgical Site Infection (SSI) (OR 2.04), urinary infection (OR 1.43), and lower respiratory tract infections (OR 1.95) in total hip replacement. Ata A et al. [7] found that the incidence of SSI in patients undergoing colorectal surgery was 3.8 times higher than in patients undergoing general surgery. For those patients undergoing colorectal surgery Insulin Dependent DM (IDDM) and Non-Insulin Dependent DM (NIDDM) were more likely than non-diabetics to develop SSI. For those patients undergoing general surgery, only IDDM were at increased risk.

Despite extensive research on diabetes related infections, there is limited data on the types of wound infections. Data on diabetes’s effect in cardiac and orthopedic surgeries is abundant, however, similar data surrounding the effect of diabetes on colectomy is lacking. Therefore, we sought to determine whether IDDM and NIDDM have different risks post-colectomy in comparison to non-diabetics using a large national-level database.


Database and study population

American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) collects preoperative, intraoperative, and 30-day postoperative information on a surgical patient from more than 250 participating hospitals. In our study, deidentified patients who underwent colectomy from 2012 to 2015 were selected from this database using the following CPT codes: 44140, 44141, 44143, 44144, 44145, 44146, 44147, 44150, 44151, 44155, 44156, 44157, 44158, 44160, 44204, 44205, 44206, 44207, 44208, 44210, 44211, and 44212.

All patients under the age of 18 were excluded. We collected the following variables from 2012 to 2015: diabetes status, age, gender, weight, SSI, UTI, pneumonia, sepsis, readmission, reoperation and length of stay. BMI was collected from 2013 to 2015 since height data for 2012 was not available.

We also collected variables such as indications, oral antibiotics, and postoperative leaks in a participant user file for colectomy separately. This file does not contain CPT codes and diabetes status, so we merged this file with the main file using Case ID as the fixed variable. There are cases listed in the main file that were not found in the colectomy specific file, and some of the CPT codes we used in the main data were not included (44155, 44156, 44157, 44158, 44211, 44212). Therefore, to limit data error, we used the merged data for only indications.

Variable definitions

Diabetes status is categorized into IDDM, NIDDM and nondiabetes. IDDM are those who require insulin alone or in conjunction with other non-insulin anti-diabetic agents to control their condition. NIDDM are those who take oral on-insulin anti-diabetic agents such as metformin. Patients who have never been diagnosed with diabetes or whose diabetes is controlled with diet and exercise alone are considered non-diabetes.

All postoperative variables must have occurred within 30 days of the procedure. SSI is limited to only postoperative findings and is categorized as superficial, deep, and organs/spaces. Superficial incision SSI involves the skin and subcutaneous tissue, deep incision SSI involves deep soft tissues including fascia and muscles, and organ/ spaces SSI involves any anatomy manipulated during the operations other than incision site. Wound disruption indicates reopening of a previously closed wound. Reoperation indicates a second operation to correct any complications at any surgical facility or hospital within 30 days of postoperative period.

Statistical analysis

We categorized our CPT filtered data into non-diabetes, NIDDM, and IDDM. In each category, we counted the number of cases and determined their percentage for specified postoperative complications and compared them across diabetic status using chisquare tests. Age was normally distributed but age above 90 was grouped as 90+, therefore, we opted to use median for the age. Age, weight, BMI, and length of stay are compared using ANOVA tests. Indications in the merged file were analyzed in a similar way.


A total of 169,325 patients were identified in the NSQIP database that underwent colectomy from 2012 to 2015. A total of 9,130 (5.39%) patients were IDDM, 14,999 (8.86%) patients were NIDDM, and 145,196 (85.75%) patients were non-diabetic. The median age of IDDM was 67, NIDDM was 68, and non-diabetics was 61 (Table 1). There was a 1:1 ratio of male to female patients who underwent colectomy despite diabetes status. Patients with IDDM weighed 26 pounds more on average than those without diabetes, while those with NIDDM weighed 20 pounds more on average compared to those without diabetes.BMI was higher in diabetic patients than nondiabetic patients (32.33 in IDDM, 31.24 in NIDDM, and 27.86 in non-diabetes).