Abdominoplasty is one of the top six cosmetic procedures performed in the United States.1,2 Although abdominoplasty is widely performed, it carries the highest risk of complications among all cosmetic procedures.3 Many surgeons choose to not perform abdominoplasty on patients who are obese, fearing that patients with a high body mass index are at increased risk for perioperative complications such as wound dehiscence, surgical-site infection, deep vein thrombosis or pulmonary embolism, and seroma.3
Although the impact of a high body mass index as an independent factor on abdominoplasty complications is unknown, comorbid conditions commonly associated with obesity, such as diabetes, hypercholesterolemia, hypertension, and ischemic heart disease, have been shown to increase complication rates.4 Complications seen in these patients include bleeding, skin or fat necrosis, wound dehiscence, surgical-site infection, hematoma, pulmonary embolism, and seroma.3,5 Seroma formation is the most common of these complications; however, the reported incidence rates range broadly from 5 to 38 percent.4,6 Clinicians are divided as to whether performing abdominoplasty with liposuction increases the risk of seroma formation.7 The senior author (J.B.) of this study previously reported seroma incidence rates of 31.2 and 16 percent in patients with and without liposuction, respectively.8 In this study, we examined the influence of obesity on perioperative abdominoplasty complication rates.
PATIENTS AND METHODS
An institutional review board–approved retrospective chart review was conducted to elucidate the effects of obesity on perioperative abdominoplasty complication rates. Using International Classification of Diseases, 10th Revision, codes, we identified 83 patients who underwent abdominoplasty with or without liposuction performed by a single plastic surgeon over a 7-year period (2009 to September of 2016) from an outpatient surgical center. A cohort of 21 obese patients were included using the standard for obesity, a body mass index greater than or equal to 30 kg/m2, as outlined by the Centers for Disease Control and Prevention. In addition, patients were included in this study only if they had not previously undergone any type of bariatric surgery (e.g., gastric bypass) or abdominal aesthetic procedure, or if they had previously lost 75 pounds or more. Patients were excluded if they did not undergo a full abdominoplasty, underwent a combined surgical procedure, or underwent liposuction in an area outside of the abdomen or flanks at the time of the abdominoplasty. Sixty-two nonobese patients were also included in the study for comparison. Data collection for the eligible patients included demographics, preoperative and postoperative weight, preoperative and postoperative body mass index, allergies, medications, comorbidities, operative technique, perioperative antibiotics, number and type of drains used, and postoperative complications.
The patient was marked in the standing position, with the midline inferior incision approximately 7 cm from the vulvar commissure on stretch. After induction with general anesthesia, the umbilicus was circumscribed and the superior skin flap was undermined using electrocautery to the costal margins laterally and to the xiphoid process in the midline. All patients underwent vertical rectus fascial plication permanent sutures. Infiltration of tumescent solution was then performed in the flanks using a lidocaine with epinephrine solution. Liposuction of the flanks was then performed using a 4-mm cannula. The abdominal flap was not suctioned in any case. The patient was then placed in a semiflexed position and the senior author then tensioned the abdominal flap in exactly the same manner in all patients. The excess infraumbilical skin and fat were completely excised. Before the final wound closure, two closed suction drains were placed in the suprapubic area. No quilting sutures or fibrin glue was used in any of the patients.
Statistical analysis was performed on both categorical and continuous outcomes. The statistical significance between continuous variables in obese and nonobese abdominoplasty patients was calculated using two-tailed t tests. The variables analyzed included body mass index, age, lipoaspirate, average drain duration, and the seroma characterization endpoints. Chi-square or Fisher’s exact test was used as appropriate to compare the outcome measures. The level of significance selected was 0.05.
Finally, a power analysis was performed to calculate the sample size needed for body mass index and seroma characterization endpoints. Power was set to 0.8 to reduce the type II error to 0.2. The pooled standard deviation was calculated using the following formula: √[(SD12 + SD22)/2]. Then, the effect size was calculated using the Cohen d formula: (M2 − M1)/SDpooled. The minimum sample size required per group was 21 patients. Data management and statistical analyses were performed using IBM SPSS Version 24.0 (IBM Corp., Armonk, N.Y.).
Of the 21 patients in the obese cohort, 20 were female and one was male. The average time of follow-up was 291 days, with an average time of follow-up of 310 days in the obese group and 265 days in the nonobese group. The average obese patient age was 40.8 years (range, 29 to 54 years). The average preoperative body mass index was 34.9 kg/m2 (range, 30.0 to 43.8 kg/m2). Patient comorbidities included smoking (9.5 percent), diabetes (9.5 percent), hypercholesterolemia (9.5 percent), and hypertension (19.0 percent) (Table 1). The only difference regarding comorbidities between the two groups that reached statistical significance was hypertension, which was 19 percent in the obese group and 3.2 percent in the nonobese group (p < 0.03).
Of the 62 nonobese patients, 61 were women and one was a man. The average patient age in this group was 43.7 years (range, 27 to 62 years). The average postoperative body mass index was 25.1 kg/m2 (range, 21.8 to 29.1 kg/m2). Patients’ comorbidities included smoking (8.0 percent), diabetes (1.6 percent), hypercholesterolemia (4.8 percent), and hypertension (3.2 percent) (Table 1).
The senior author performed all procedures to ensure that operative technique for all patients was uniform without variability. Preoperative and postoperative instructions were the same for all patients. All patients underwent the abdominoplasty in the practice’s outpatient surgery center.
With regard to the complications we observed, wound dehiscence occurred in nine patients (10.8 percent). Surgical-site infection occurred in seven patients (8.4 percent), and two patients developed hematomas (2.4 percent) (Table 2). No patients developed clinically evident venous thromboembolism on physical examination.
Twenty patients (95 percent) in the obese cohort and 49 patients (79 percent) in the nonobese cohort had liposuction of the flanks and hips concurrently with abdominoplasty. The average lipoaspirate amount from the obese cohort was 1237 cc, whereas the amount in the nonobese cohort was 636 cc. This was found to be statistically significant p < 0.001 (Table 3).
Seroma in this study was defined as being present when two or more aspirations of at least 40 cc were performed to drain the collection or if the collection required catheter drainage or a sclerosing agent. The diagnosis of a postoperative seroma was made based on abdominal wall swelling along with the presence of a fluid wave. Once the number of postoperative aspirations reached our criteria for seroma formation, the decision to place a drain was based mainly on the overall volume of the aspirations. Those seromas with a larger volume had drains placed. When sclerosis of the seroma cavity was performed, alcohol was the sclerosing agent of choice. In the present study, the overall seroma formation rate occurred in 17 patients (20.4 percent). It was observed in three patients (14.2 percent) in the obese cohort and in 14 patients (22.5 percent) in the nonobese group. The difference did not reach statistical significance (p < 0.419). The average time of seroma formation was 22.3 days postoperatively in the obese patients and 18.8 days in the nonobese patients (p < 0.354). We then looked at various seroma characteristics between the two groups (Table 4). The average number of aspirations was 2.33 in the obese group versus 5.43 in the nonobese group (p < 0.332). The average aspirated amount was almost double in the obese group at 103.3 cc versus 57.98 cc in the nonobese group. This did not reach statistical significance (p < 0.213). When seromas were identified, we looked to see whether there was any difference in the management with either aspiration alone or aspiration with guided drain placement or a sclerosing agent. We did not observe a difference between the two groups (Table 5).
When looking at the duration of drains kept in the patient, there was a significantly longer duration in the obese patients at 10.8 days compared to the nonobese patients at 8.0 days (p < 0.013). It is the authors’ practice to place the patient on antibiotics postoperatively. There was no difference in length of antibiotic duration between the two groups at 6.52 days in the obese patients compared to the nonobese patients at 6.61 days (p < 0.743).
An odds ratio was performed to evaluate the various patient comorbidities we analyzed. We did see an increased risk of developing complications if the patient had a medical history of hypertension (OR, 7.06; p < 0.031) (Table 6). With regard to the various complications observed, we did not see any difference.
Despite various complications such a seroma, hematoma, surgical-site infection, and venous thromboembolism, abdominoplasty remains one of the top cosmetic procedures in the United States according to the American Society for Aesthetic Plastic Surgery. Obesity is on the rise in the United States and in other areas of the world. As obesity is considered a comorbidity for surgery in general, we sought to examine the effects of a high body mass index on abdominoplasty, an area that is seldom researched in nonbariatric patients.
A case-control study conducted by Murshid and colleagues examined the effect of body mass index on abdominoplasty complications.3 They noted that the incidence of seroma in their study was 15 percent, which is less than the reported worldwide rate of 30 percent. Complications affected both groups; however, complication rates were higher among the elderly, smokers, and those with other comorbid conditions, and no complications occurred in patients without comorbid conditions. Our study shows a similar complications rate for all complications analyzed, including that of seroma. Conversely, a similar study conducted by Kim and Stevenson did find a higher rate of seroma in overweight and obese patients combined.4 Our study divides the patients into obese and nonobese categories and therefore our article and the one by Kim and Stevenson are not comparable. In addition, we did not see any incidence of clinical venous thromboembolism in our patients studied. Our patients were given perioperative deep venous thrombosis prophylaxis based on their Caprini score. All patients had sequential compression devices placed on their lower extremities before induction of anesthesia, and patients with Caprini scores greater than 3 also received 5000 U of heparin subcutaneously. Although we did not see any of our patients with evidence of venous thromboembolism, we must disclose that patients were not screened postoperatively with lower extremity ultrasound. We relied on clinical suspicion and physical examination to determine whether further ultrasonographic studies were warranted. Given that we did not perform routine ultrasound on all of the patients, there remains the possibility of subclinical deep venous thrombosis.
With regard to seroma formation, we did not see a statistically significant difference between the two groups. However, based on the percentage of patients with seromas, there was a higher number of seromas in our nonobese patients compared with our obese patients. One reason for the increased number of seromas observed in the nonobese patients might be the ease with which they could be detected on physical examination. A thicker anterior flap in an obese patient could mask the seroma on examination.
A majority of the patients observed underwent liposuction of the flanks in both groups. No liposuction of the anterior flap was performed. We did see a difference in the amount of lipoaspirate in the obese patients compared with the nonobese patients. This difference is understandable, as the amount of liposuction needing to be performed in the obese patients is commensurate with the need to obtain a better contour in the face of more subcutaneous tissue. We did also notice a statistically significant difference in the drain duration in the obese patients compared with the nonobese patients. The difference was approximately 2 days on average. It is the senior author’s practice to remove the drains should their output be less than 30 cc over 24 hours. The increased length could be a reason for the overall decrease in seroma in the obese patients we observed; however, this was not statistically significant.
For patients with a high body mass index, quality of life may be enhanced following an abdominoplasty procedure. To our knowledge, there is limited evidence regarding the long-term outcomes of an abdominoplasty in nonbariatric patients with a high body mass index. Stevens and colleagues suggest that patient exclusion criteria should not be based on body mass index alone, but that obesity-related comorbidities be considered and patients evaluated on an individual basis.1 A similar study found a higher complication rate in the obese patients compared with the nonobese patients.9 The main difference between the complications rates was likely from the inclusion of patients who underwent weight loss procedures. Patients who have had significant weight loss are at increased risk of developing complications.10
Our study adds to the limited current body of knowledge regarding complication rates in nonbariatric patients with a high body mass index. Although we do acknowledge that having more patients in the study would make our findings much more powerful, we do believe that we have a sufficient number of patients to show that operating on obese patients is safe if not as safe as operating on nonobese patients. The results of our chart review suggest that physicians should not immediately advise obese patients against undergoing abdominoplasty. Moreover, our results suggest that abdominoplasty in these individuals may be a safe, efficacious procedure.
Our study results suggest that a body mass index greater than 30 kg/m2 in and of itself should not be viewed as a strict contraindication to abdominoplasty. Plastic surgeons should evaluate patients on a case-by-case basis and patients should be counseled as to the potential perioperative risks of this procedure. Moreover, surgeons should discuss realistic postoperative goals with potential candidates for surgery. In our study, postoperative complication rates were consistent with rates reported in the general population and much lower than in a previous report in the literature specific to obese patients. Thus, our results indicate that despite the high incidence of perioperative complications, anticipation of these complications should not immediately preclude the potential benefits of abdominoplasty for obese patients.
1. Stevens WG, Spring MA, Stoker DA, Cohen R, Vath SD, Hirsch EM. Ten years of outpatient abdominoplasties: Safe and effective. Aesthet Surg J. 2007;27:269–275.
3. Murshid M, Khalid KN, Shakir A, Bener A. Abdominoplasty in obese and in morbidly obese patients. J Plast Reconstr Aesthet Surg. 2010;63:820–825.
4. Kim J, Stevenson TR. Abdominoplasty, liposuction of the flanks, and obesity: Analyzing risk factors for seroma formation. Plast Reconstr Surg. 2006;117:773–779; discussion 780781.
5. Grazer FM, Goldwyn RM. Abdominoplasty assessed by survey, with emphasis on complications. Plast Reconstr Surg. 1977;59:513–517.
6. Araco A, Gravante G, Araco F, Sorge R, Cervelli V. Postoperative seromas after abdominoplasty: A retrospective analysis of 494 patients and possible risk factors. Plast Reconstr Surg. 2009;123:158e–159e.
7. Matarasso A. Discussion: Abdominoplasty, liposuction of the flanks, and obesity: Analyzing risk factors for seroma formation. Plast Reconstr Surg. 2006;117:780–781.
8. Najera RM, Asheld W, Sayeed SM, Glickman LT. Comparison of seroma formation following abdominoplasty with or without liposuction. Plast Reconstr Surg. 2011;127:417–422.
9. Rogliani M, Silvi E, Labardi L, Maggiulli F, Cervelli V. Obese and nonobese patients: Complications of abdominoplasty. Ann Plast Surg. 2006;57:336–338.
Copyright © 2019 by the American Society of Plastic Surgeons
10. Sanger C, David LR. Impact of significant weight loss on outcome of body-contouring surgery. Ann Plast Surg. 2006;56:9–13; discussion 13.