Physiology of the Bariplastic Patient

by Marcelo M. Ghersi, MD; Martin I. Newman, MD, FACS; Michel C. Samson, MD, FRCS(C), FACS; and Laura DeOliveira, PC-S

INTRODUCTION
The increase in bariatric surgical procedures for weight loss seen in the last decade has had a significant impact on adjunctive medical and surgical services. The impact of these procedures on the field of plastic surgery is well established. An unprecedented influx of massive weight loss patients seeking body contouring has resulted in the development of a new branch of plastic surgery devoted to this patient population. The term bariplastic surgery has previously been used to describe this evolving subspecialty.[1]

Massive weight loss patients present a unique set of issues that pose a challenge for the plastic surgeon. In addition to the skin and soft tissue-related functional and aesthetic concerns for which they seek surgery, bariatric patients are characterized by a predictable set of physiologic, metabolic derangements. These are often interrelated, and include nutritional deficiencies, anemia, unstable weight loss, and poor patient compliance.[2]

In addition, much of the natural skin elasticity is lost in these individuals.Plastic surgeons who are considering surgery for these special patients must account for these specific issues in their initial evaluation and, when necessary, provide or refer patients to appropriate treatment prior to surgical intervention to optimize outcomes and ensure patient safety. This article aims to further describe the main management issues associated with the bariplastic patient and to offer recommendations for the plastic surgeon performing body contouring procedures.

Nutritional Deficiencies and Anemia
Surgical procedures designed to promote weight loss may be restrictive, malabsorptive, or a combination of restrictive and malabsorptive. Restrictive procedures result in the decrease of dietary intake. Malabsorptive procedures bypass portions of the gastrointestinal tract whose function is to take up critical metabolic factors. Combination procedures, such as the popular gastric bypass procedure, reduce both dietary intake as well as the absorption of critical metabolic elements.
Thus, massive weight loss patients will often present in a malnourished state. This may be especially true if they are early in their course of weight loss. Traditionally, surgeons have measured serum proteins, such as albumin and prealbumin, to assess nutritional state and the ability of a patient to heal wounds. In addition to functioning as a surrogate marker for a depleted nutrition state, low serum albumin concentrations may also reduce intravascular oncotic pressure. As a result, some authors have suggested that patients depleted of protein storages are more prone to seroma formation. Plastic surgeons experienced in managing this patient population are well familiar with the high rate of seroma seen following body contouring procedures. The ability to synthesize collagen is also an important task of the post-plastic surgery patient. Collagen synthesis requires a multitude of protein residues as well as elemental co-factors. For these reasons, it may be prudent to evaluate serum albumin and prealbumin levels as part of the preoperative workup. Deficiencies, if noted, can be treated through dietary adjustments.

Many clinicians have adopted a serum albumin concentration of 3.5g/dL or above as a marker of adequate protein stores.[3] In our practice, this is best managed by the dietitian of the multidisciplinary bariatric team. However, as bariatric surgery continues to become more popular, many primary care physicians are becoming adept at the management of these issues as well.

In addition to deficiencies of proteins, fats, and carbohydrates, deficiencies of vitamins, minerals, and critical co-factors may also be present in the post-bariatric patient. In our practice, preoperative evaluation involves, among other investigations, a complete metabolic profile. However, trace elements are less easily tested directly. Therefore, we place significant weight upon the initial interview to determine whether or not our patients are supplementing their diet with calcium, zinc, multivitamins, and B vitamins as well as folate and B12. Again, we specifically ask our bariatric patients if they take these supplements because many individuals do not consider these “medications.” If a post-bariatric patient does not take these supplements regularly, we investigate the reason. In some cases, their specific bariatric procedure does not require them to take these supplements. However, in other cases we learn that the patient has simply been noncompliant. This is an important component of a patient’s history and can be telling as to his or her plastic surgical compliance. Should a deficiency be identified either by laboratory investigation or by history, the operating surgeon may wish to refer the patient to a bariatric dietitian or a primary care physician familiar with the management of these issues prior to surgical intervention.

Nausea and vomiting, not uncommonly seen following bariatric surgery, further exacerbate these metabolic derangements. In some instances, such deficiencies may have profound effects on the overall health of the patient. Thiamine deficiency, for example, may progress to encephalopathy and eventually irreversible dementia unless it is promptly diagnosed and treated. Patients with severe and acute thiamine deficiency may develop Korsacoff’s syndrome, Wernicke’s syndrome, or cardiac beriberi. Mental status changes, ocular palsies, or peripherial neuritits should prompt the clinician to further study levels of thiamine. If low, almost immediate relief of symptoms can be achieved with intravenous supplementation.

It is also not uncommon for the bariatric patient to present to the plastic surgical practice in an anemic state. The ability to absorb folate and B12, factors critical in the synthesis of red blood cells, is compromised by malabsorptive procedures. In restrictive procedures, decreased dietary intake of iron, folate, and vitamin B12-containing foods may as well contribute to the chronic anemic state often seen.

The anemic patient is a concern on several fronts. On the one hand, patients must be medically stable for general anesthesia because many massive weight loss body contouring procedures require this. Severe anemia, especially with a cardiac history, may be a contraindication to elective surgical intervention. On the other hand, some body contouring procedures may be associated with significant surgical blood loss. Large perforating vessels are often encountered in the dissection of subcutaneous tissue in the massive weight loss patient. Failure to identify and obtain control of these large and numerous perforators can result in an unexpectedly high blood loss. Not only is surgical bleeding a consideration, in addition, large amounts of soft tissue may contain a significant amount of intravascular volume. The debridement of a massive pannus, for example, may impose a greater than appreciated surgical blood loss than expected. Finally, oxygen is a critical factor in wound healing. An anemic state may compromise the ability of the body to deliver adequate oxygen to healing wounds and therefore may contribute to wound healing problems.

Most patients who present to our practice routinely supplement their diet with folate and multivitamins and also undergo monthly B12 injections. However, during the initial patient interview, unless this is volunteered, the surgeon may wish to specifically ask these questions because many patients do not consider folate, B12, and multivitamins “medications.” Inadequate B12 and folate levels may also lead to elevated homocystine levels. Elevated homocystine levels have been implicated in myocardial infarction.[4] Should an anemic state be identified, as most often is the case, consideration should be given to the degree of anemia. If the anemia is considered significant by the operative surgeon, referral to a primary care physician or hematologist may be in order. Some plastic surgeons choose to treat this problem through their practice. However, one should note that anemias seen in the massive weight loss patient are not often easily corrected with simple supplemental iron.

Finally, in anticipation of surgical blood loss, which may compound a pre-existing anemic state, the surgeon may wish to discuss with the patient the possible need for blood transfusion at some point during his or her course. In our practice, during the initial interview process, we ask our patients if they have an aversion to accepting blood transfusion should this be necessary. Nevertheless, we do not routinely collect autologous blood except in special cases.

Compliance
Despite generally having good disposition and compliance as a group, some bariatric patients have a tendency to become less compliant as time unfolds. Individuals with severe preoperative eating disorders and those that come from lower socioeconomic backgrounds are particularly susceptible to poor compliance. Such individuals become less attentive to the quality and character of their diet, making them more prone to developing deficiencies of proteins, functional red blood cells, vitamins, and minerals.[5,6]

Massive weight loss patients benefit from complete care as provided by their primary care physicians and should be seen on a regular basis. Moreover, many continue to be afflicted with conditions related to obesity, such as diabetes, coronary artery disease, peripheral vascular disease, and arthritis, adding to the potential morbidities they may encounter with body contouring surgery. For these reasons, we recommend that all candidates for plastic surgery be cleared and monitored by physicians familiar with their overall profiles.

Skin Elasticity
The post-bariatric patient’s skin lacks the elasticity seen in non- massive weight loss patients. As a result, following even the most aesthetically admirable of operative results, laxity often recurs. Both the patient and the surgeon should be aware of this phenomenon as it may predispose this patient population to a higher revision rate to maintain aesthetic ideals.

Conclusion
Massive weight loss patients seeking body contouring present with specific and important management challenges that can be recognized and addressed by the plastic surgeon. Nutritional deficiencies, anemia, and compliance issues are just some of the several aspects that are important among this patient population.

Patient selection in post-bariatric body contouring surgery is of utmost importance as well. The ideal surgical candidate is motivated, stable in weight with body mass index less than 30, actively partakes in exercise, has healthy eating habits, and refrains from smoking. Once a patient has been selected, perioperative optimization of the nutritional status can be effectively achieved with the assistance of a multidisciplinary team and patient cooperation.

Body contouring surgery can be an excellent adjunct to bariatric surgery. It allows for functional as well as aesthetic benefits, which are important for the emotional and social wellbeing of these patients. The ability to detect and appropriately address the specific issues that affect their surgical welfare can only serve to provide them with the best possible outcome. Applying the principles and recommendations discussed herein will allow the body contouring surgeon to maximize the chances of a successful and safe outcome.

REFERENCES
1.    O’Connell JB. Bariplastic surgery. Plast Reconstr Surg. 2004;113(5):1530.
2.    Kenkel JM, et al. The Physiological Impact of Bariatric Surgery on the Massive Weight Loss Patient. Plast Reconstr Surg. 2006;117(1 Suppl): January 2006;14S–16S.
3.    Stahl S, Sernol A, Donovan W, Spira M. The perioperative management of the patient with pressure sores. Ann Plast Surg. 1983;11:347.
4.    Dixon JB, Dixon ME, O’Brien PE. Elevated homocysteine levels with weight loss after Lap-Band surgery: higher folate and vitamin B12 levels required to maintain homocysteine level. Int J Obes Relat Metab Disord. 2001;25(2):219–227.
5.    Toussi R, Fujioka K, Coleman KJ. Pre- and Postsurgery Behavioral Compliance, Patient Health, and Postbariatric Surgical Weight Loss. Obesity (Silver Spring). 2009.
6.    Elkins G, Whitfield P, Marcus J, et al. Noncompliance with behavioral recommendations following bariatric surgery. Obes Surg. 2005;15(4):546–551.

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