Breast Reduction in Adults: Identifying Risk Factors for Overall 30-Day Postoperative Complications

Abstract

Background

Breast reduction is a commonly performed procedure. Understanding the postoperative complication profile is important for preoperative planning and patient education.

Objectives

The authors sought to assess complication rates following breast reduction in females and identify potential risk factors.

Methods

We assessed the records of the American College of Surgeons National Surgical Quality Improvement Program participant use files that include patients who underwent breast reduction for macromastia between 2005 and 2016. Relevant patient and postoperative data were extracted, and factors affecting complications were analyzed utilizing the logistic regression model.

Results

We identified 20,001 women aged a mean 43.9 years who underwent breast reduction. The number of patients who developed ≥1 complication was 1009 (4.3%). Our adjusted analysis revealed that outpatient setting (odds ratio [OR] = 0.600) and performance of the surgery by the attending surgeon alone (OR = 0.678) were associated with lower odds, whereas higher body mass index (OR = 1.046) and smoking (OR = 1.518) were associated with higher odds for complications following breast reduction. Outpatient setting (OR = 0.317) was also associated with lower odds whereas smoking (OR = 1.613) and American Society of Anesthesiologists class were associated with higher odds of returning to the operative room. These findings were consistent in our subgroup analysis for wound-related complications.

Conclusions

Our study shows that patient characteristics such as smoking and body mass index may increase complication rates after breast reduction. Clinical factors such as inpatient setting may also increase risk of complications following breast reduction. It is critical to understand the effect of these factors to better predict postoperative outcomes and ensure thorough patient education.

Macromastia, or abnormally enlarged breasts, is a burdensome condition that can cause significant physiological and psychosocial distress in women. Breast reduction mammoplasty is a surgical procedure designed to reduce excess glands, tissue, and skin to treat symptoms of macromastia or as an aesthetic procedure.¹ Macromastia often limits individuals physically by causing pain in the upper torso resulting from the amount of weight in the breasts straining the muscles and nerves.^2,3 This strain may lead to headaches, neck pain, shoulder pain, spinal pain, dermatitis of the inframammary fold, and pressure on the brachial plexus by brassiere straps.^4,5 Psychosocially, breast hypertrophy is often associated with kyphosis, as patients may hunch their back to attempt to conceal a source of embarrassment.³ Additionally, significant psychosocial health problems may arise as a result of low self-esteem and body image, wardrobe concerns, and social anxiety.³ Plastic surgeons performing a reduction mammoplasty aim to decrease breast volume, preserve as much sensation and function as possible, and contour the breasts into an aesthetically more superior shape that complements the patient’s anatomy.⁶

Reduction mammoplasty surgical techniques have been developed and modified over the last several centuries, beginning in Europe and then eventually in the United States.⁷ Mammoplasty techniques have been continually researched and modified to decrease risks of complications and scarring and to improve outcomes and patient satisfaction.^6-8 Patient satisfaction and outcomes vary with the patient’s perception of an esthetically pleasing breast, which in turn varies across populations. This results in diverse surgical techniques that may result in varying postoperative courses.⁹ The first breast reduction surgery was implemented by Paulus Aegineta (AD 625-690) for the treatment of gynecomastia, according to Letterman and Schurter.¹⁰ From that point, the surgery gradually was performed, improvised, and analyzed by mathematicians with geometrical foundations creating the ideal conical projection and shape.¹⁰ The surgery rapidly increased in the 1980s as surgeons aimed to create the most precise and concealed incision scars utilizing the classic techniques previously perfected.¹⁰ In the United States, approximately 40,000 reduction mammoplasties were performed in 1988, and this number doubled by the late 1990s.¹⁰ These early techniques included basic principles that laid the groundwork for the approximately 70 different techniques in the present day.¹⁰

Breast reduction was the seventh most commonly performed plastic surgery procedure in 2016, with 112,142 surgeries performed on women nationally.¹¹ This represents a 134.2% increase since 1997.¹¹ However, studies have reported variabilities in complication rates ranging from 43.0% to 53.9%.^12-14 These results may be influenced by details such as small sample sizes, risk factors associated with the complications, or an inpatient vs outpatient setting. According to a meta-analysis performed in 2016, the strongest predictor of complications was obesity (patients with a body mass index [BMI] > 30).¹⁵ These patients tend to have higher rates of infections due to relatively low vascularity of the adipose tissue, capillary recruitment, and acetylcholine-mediated vasodilation.^15,16 Smoking also was shown to be a high risk factor associated with wound dehiscence, tissue and nipple necrosis, decreased blood flow and endothelial walls, thrombogenicity, and increased catecholamines.^15,17 A study executed utilizing a population-level analysis indicated no statistically significant association with age and surgical complication. Other risk factors can include mass of resection, hypertension, fibromyalgia, and previous breast surgeries.¹⁵

The following retrospective study sought to assess complication rates following breast reduction in females with macromastia and identify potential risk factors. Identification of these risk factors is crucial for optimum preventative measures and for preparation of the patient-specific modifications to surgical care and techniques.

METHODS

The authors (C.S. and P.A.) conducted a retrospective review of the records of the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) participant utilization files that include patients who underwent breast surgery for various indications between January 2005 and December 2016. Patient characteristics and overall 30-day postoperative complication rates were extracted from the registry of patients by 2 authors (C.S. and P.A.) for statistical analysis. This research was conducted in accordance with the Declaration of Helsinki.

Database

The ACS NSQIP is a prospective database that collects data for more than 300 variables. Data are collected regarding preoperative risk factors and intraoperative factors. It also includes 30-day postoperative mortality and morbidity outcomes for patients who underwent major surgical procedures in both in-patient and out-patient settings. The database is compliant with the Health Insurance Portability and Accountability Act and is exempt from institutional review board review. We identified all patients in the registry who underwent breast reduction surgery employing the Current Procedural Technology code 19318, which is the code under the range “Repair and/or Reconstruction Procedures on the Breast.”

We accessed information regarding patient demographics and complications in these patients. All complications noted as part of the database occurred within a 30-day time period postoperatively. Important information regarding factors that affect complication rates in breast reduction surgery was also extracted based on existing literature. We also gathered information regarding patients returning for surgery.

Statistical Analysis

A logistic regression model was utilized to evaluate potential factors that may influence overall complication rates in adult women undergoing breast reduction surgery when assessed 30 days postoperatively. The following factors were included in our regression analysis: race, admission status, resident involvement, age, BMI, diabetes, smoking, American Society of Anesthesiologists (ASA) class, and surgery duration. Additionally, complications were subgrouped into (1) wound-related complications, and (2) other systemic complications and applied the logistic regression analyses to each subgroup. Wound-related complications included superficial and deep surgical site infections, wound dehiscence, and wound infection. We also utilized the logistic regression model and the same factors mentioned above to analyze the impact on rate of return to the operating room for breast reduction surgery in adult women.

All statistical analysis was conducted employing STATA (v0.13.0, StataCorp, College Station, TX).

RESULTS

A total of 20,001 patients who underwent breast reduction surgery from 2005 to 2016 had their data entered into the ACS NSQIP. Of these, 1009 (4.3%) developed ≥1 complications. Patient demographics are described in Table 1; a comprehensive list of all complications that occurred in this cohort may be found in Table 2.

Our analysis showed that outpatient setting (odds ratio [OR] = 0.600, 95% confidence interval [CI] = 0.487-0.739) as well as when the procedure was performed by the attending surgeon alone (OR = 0.678, 95% CI = 0.506-0.912) were both associated with lower odds of developing postoperative complications. Conversely, smoking (OR = 1.517, 95% CI = 1.196-1.925), increased BMI (OR = 1.046, 95% CI = 1.033-1.059), and increased duration of surgery (OR = 1.001, 95% CI = 1.000-1.002) were associated with higher odds of complications (Table 3). Our analysis of the wound-related complications identified the same factors as significant contributors. Wound-related complications had a higher odds of occurring with increased BMI (OR = 1.050, 95% CI = 1.037-1.064) and in patients with a history of smoking (OR = 1.751, 95% CI = 1.372-2.234); lower odds were seen when attendings performed the surgery alone (OR = 0.659, 95% CI = 0.481-0.904) compared with residents (reference group). These findings have been summarized in Table 4. For non–wound-related systemic complications, higher BMI (OR = 1.033, 95% CI = 1.006-1.061) and increased duration of surgery (OR = 1.005, 95% CI = 1.003-1.007) were associated with significantly increased odds of complications, whereas outpatient surgery was associated with lower odds (OR = 0.214, 95% CI = 0.145-0.318). These findings have been summarized in Table 5.

We also observed that treatment in the outpatient setting was associated with a lower odds of unplanned reoperation (OR = 0.317, 95% CI = 0.242-0.417), whereas smoking (OR = 1.613, 95% CI = 1.137-2.289) and higher ASA class (Table 6) were associated with a greater odds of returning to the operating room.

DISCUSSION

Our retrospective review evaluated national breast reduction complication rates from 2005 to 2016 utilizing NSQIP. Our analyses showed that smoking and increased BMI may be associated with increased risk of developing complications after breast reduction surgery. This risk was lower when the procedure was performed by an attending surgeon alone (ie, without resident involvement) and when the procedure was performed in an outpatient setting.

The ill effects of smoking on wound perfusion and thereby healing, possibly due to nicotinic vasoconstriction, have been well established. A wide consensus exists among plastic surgeons that patients must refrain from smoking prior to breast reduction surgery. Cunningham et al as part of their 9-month, prospective, multicenter trial, The Breast Reduction Assessment: Values and Outcomes study, showed that patient smoking status was directly related to delayed wound healing.¹² Bartsch et al measured cotinine, the most common metabolite of nicotine, in their mammaplasty reduction patients with delayed wound healing and found statistically significantly higher preoperative and postoperative values.¹⁸ Lewin et al found that smokers had a significantly higher rate of developing postoperative complications and were 2 times more likely to develop infections, which was the most common complication in their study.¹⁹ There is no consensus among plastic surgeons as to how long a patient must refrain from smoking before breast reduction surgery. A common recommended protocol is to refrain from smoking for 4 weeks, and if a surgeon suspects noncompliance this can be confirmed utilizing a urine nicotine test.²⁰

Increased BMI has been identified as an important risk factor for several diseases often requiring lifestyle modification as part of their treatment. Lista et al showed that patients with increased BMI were more likely to develop postoperative complications. Similarly, several surgical procedures also associate an elevated BMI with increased intra- and postoperative complications. Lewin et al found a significant association between high BMI and postoperative infections and fat necrosis.¹⁹ Chun et al showed that, of their 675 bilateral reduction mammaplasties, 75 patients (11%) developed complications; among these, patients with a BMI of 35.6 had twice the possibility of developing complications (OR = 2.002, P = 0.004).²¹ Considering that BMI and smoking are the most common factors influencing complication rates in breast reduction surgery, it may be beneficial to establish a standardized screening protocol based on these factors.

Resident involvement in assisting and performing surgical procedures is crucial to maintain continuity of skill and ability to the succeeding generation of surgeons. However, attending surgeons must take great care that training the surgeons of tomorrow does not negatively impact patient care. Krell et al documented complication rates and resident involvement in 17,057 patients who underwent primary laparoscopic gastric bypass. They noticed that resident involvement was independently associated with a higher incidence of wound infection (OR = 2.06, 95% CI = 1.24-3.43) and venous thromboembolism (OR = 2.01, 95% CI = 1.19-3.40).²² However, most studies in plastic and reconstructive surgery show similar wound complication and infection rates with and without resident involvement.^23,24 The cases with resident involvement were underrepresented in this dataset. Also, resident cases had a higher incidence of smokers; however, the mean age was comparable between the 2 groups and in fact the nonresident patient group had a higher BMI. Residents training at academic institutions are often involved in surgeries for patient populations with a greater likelihood of comorbidities, which could be a contributing factor. It is also possible that our findings were due to missed complications in the nonresident involvement cases if they occurred after 30 days. It must also be noted that the patient population presenting to academic institutions where residents train may differ from those seen in private practice settings. In any case, we believe that the results related to resident involvement should be interpreted with caution because many confounding factors may play a role.

Breast reduction surgery has shifted from being an inpatient procedure to more commonly an outpatient procedure. Short et al in 1996 reported their experience with 331 cases, of which 170 (51%) were inpatients and 161 (49%) were outpatients. Over a 5-year (1989-1993) period, their inpatients decreased from 91% to 21% and outpatients increased from 9% to 79%. Forty-one percent of their inpatients developed complications whereas only 29% of their outpatient cases developed complications.²⁵ It is important that surgeons and hospitals keep in mind relevant information regarding contributing factors to postoperative complications to maximize patient safety.

A previous study by our group outlined a comprehensive departmental model for patient service, quality, and excellence.²⁶ In particular, some of the interventions we employed include weekly comprehensive and multidisciplinary meetings to discuss patient safety concerns and identify possible causes and solutions; prospective monitoring of safety events, complications, and patient satisfaction; and implementation of quality improvement projects by faculty and residents. Such comprehensive measures implemented at a national level will enable the healthcare community to achieve excellence in patient care and value-based reimbursement.

Complications have a significant impact on healthcare cost. But the severity of complications is an important confounder in this analysis. Complications may be major—requiring readmission or reoperation, or may be minor—which may require minimal outpatient care or simply observation. Major complications have a significant impact on healthcare costs compared with minor complications, which in this context may be inconsequential. Furthermore, difference in timing of the complication—acute, subacute, or late, also may have a varying effect on cost. Predicting causes of complications and developing strategies to mitigate the same in a practical manner will no doubt help improve the efficiency of the healthcare system.

The limitations of our study include its retrospective nature. Some limitations also extend directly from those deliberately introduced as part of the database to safeguard the privacy of patients (eg, removal of absolute dates). Additionally, the database does not differentiate complication severity, and it is possible that some of the included wound complications were minor or superficial. Because severe complications often have a significant impact on patient care (eg, complications requiring wound debridement), ideally we would analyze these complications separately. Other limitations are due to resource constraints such as collection of generic variables only and the database’s 30-day postoperative follow-up time period, which subsequently omits any complications arising after that period.²⁷

CONCLUSIONS

Breast reduction has been associated with relatively few complications. However, our study shows that patient characteristics such as smoking and BMI may increase complication rates after breast reduction. Clinical factors such as inpatient setting may also increase risk of complications following breast reduction. Increased complication rates may also influence a return to the operating room for subsequent revision procedures. It is therefore critical to understand the effect of these factors to better predict postoperative outcomes and appropriately educate patients preoperatively.

Disclosures

The authors declared no potential conflicts of interest with respect to the research, authorship, and publication of this article.

Funding

The authors received no financial support for the research, authorship, and publication of this article.

REFERENCES