**4. Rehabilitation following bariatric surgery**

Formulation of an individually-tailored rehabilitation program based on each bariatric patients' clinical complexity should be the priority to holistically manage such clients using a multidisciplinary team approach. Multidisciplinary teams offer the best post-operative outcomes [28], addressing quality of weight loss, medical and psychiatric comorbidities, psychosocial problems and physical disability [29]. To ensure a smooth transition from prehabilitation through postoperative rehabilitation, the physical, biopsychosocial model continues to be relevant and emphasis should be placed on preventing surgical-related complications, secondary prevention of CVD, addressing bariatric-related disabilities, psychological and socio-environmental barriers, enhancing physical function through adapted physical activities, education on nutritional management as well as implementation of sustainable weight management strategies.

The post-bariatric surgery management will require coordinated care from a multidisciplinary team of healthcare providers starting from immediate post-op followed by long-term management. The integration of several medical specialties including clinical nutrition, endocrinology, psychiatry [1], rehabilitation medicine, as well as allied health professionals including physiotherapy, occupational therapy, and nursing should be included as part of the core management team. Each team member should provide detailed assessment of impairments, outline prevention strategies and provide solutions for disease management alongside implementation of a functional restoration program. A functional restoration program postoperatively should aim to not only achieve marked weight loss, but also prevention of weight regain, progression of obesity-associated comorbidities, restoration of physical functioning and increase health-related quality of life.

A post-op functional restoration program can be broadly grouped into two categories:

	- i.Nutritional management
	- ii.Weight management
	- i.Physical activity and exercise training
	- ii.Psychosocial

### **4.1 Medical**

#### *4.1.1 Nutritional management*

The goal of weight loss procedures in general is to either reduce the amount of consumed calories (restrictive) per day or to alter the absorption of the fat (malabsorption) in the food one consumes. For restrictive procedures such as vertical banded gastroplasty (VBG) or laparoscopic adjustable gastric banding (LAGB), that has no malabsorption effect, the volume of food intake will be reduced overall, hence, some nutritional deficiencies may occur. Malabsorptive surgeries such as or biliopancreatic diversion (BPD), gastric sleeve (GS) or Roux-en-Y gastric bypass (RYGB) causes alterations in the intestinal tract and creates challenges in maintaining healthy levels of nutrients including proteins, vitamins and minerals as well as reduction in the absorption of calcium and iron [30].

#### *From Prehab to Rehab: The Functional Restoration of a Bariatric Individual DOI: http://dx.doi.org/10.5772/intechopen.94418*

Management of these potential nutritional deficiencies is therefore paramount for patients undergoing bariatric surgery and strategies should be employed to compensate for food reduction or food intolerance to reduce the risk for clinically important nutritional deficiencies. Signs and symptoms of protein deficiency such as hair loss, fatigue and leg swelling should be monitored. Heber et al. recommended the nutritional management should include: an average of 60 – 120 g of protein daily in all patients to maintain a lean body mass during the weight loss and for the long term to prevent protein malnutrition and its effects, and this is especially important in those treated with malabsorptive procedures to prevent protein malnutrition and its effects [28].

Long-term vitamin and mineral supplementation is recommended in all patients undergoing bariatric surgery with those who have had malabsorptive procedures requiring potentially more extensive replacement therapy to prevent nutritional deficiencies [28]. Specific signs and symptoms of common vitamin and mineral deficiencies include bone pain (calcium), fatigue (iron, vitamin B12), brittle nails (zinc), poor wound healing (vitamin E), easy bruising (vitamin K), numbness and tingling in the hands and feet (vitamin B1). Deficiencies in fat-soluble vitamins A, D, E and K is expected therefore, it is essential for patients to take specially formulated vitamins (A, D, E, and K in water-soluble form). B-complex vitamins, iron, and calcium must also be supplemented at higher than daily recommended levels, because of the impact of the gastric bypass procedure on their absorption. Due to the body's limited ability to a absorb calcium postoperatively and the acidic environment needed for absorption, a citrated form of calcium is recommended and taken in amounts that meet or exceed daily recommended levels [30]. For maximal absorption, elemental calcium supplements should be taken in divided doses not to exceed 500 mg, three times daily [30]. Iron deficiency is also very common after malabsorptive procedures and iron-fortified foods such as leafy greens, legumes, seafood, iron-fortified grains, red meat and poultry should be consumed on a regular basis. Routine laboratory testing of the iron stores postoperatively may be required with iron supplementation either orally or parenterally administered accordingly by the healthcare provider.

Dumping syndrome may occur as a result of malabsorptive procedures such as RYGB where the food content empties into the small intestine faster than usual. Patients may experience symptoms such as abdominal cramping, nausea and vomiting due to the small intestine being unable to absorb the nutrients from food that have not been fully digested in the stomach. Reactive hypoglycaemia may also occur due to the large surge of insulin after "dumping". Dietary changes is the mainstay of treatment for dumping syndrome. Avoidance of simple carbohydrates such as white flour and sugar, consumption of more complex carbohydrates such as whole grain and sources of protein such as fish, meat, beans, legumes and soy are recommended. Frequent loose stools is also a potential side-effect of malabsorptive procedures. It is critical that patients stay adequately hydrated to reduce the risk of dehydration. Lack of mobility may also predispose patients with regular soiling of the perineum to skin pathologies including development of pressure areas. Nutritional education is vital to the success of the surgery and prevention of complications. Regular follow-up and periodic monitoring of nutritional deficiencies postoperatively will be required for detection and correction. Lifelong supplementation of daily mineral, multivitamin and micronutrients must be considered.

### *4.1.2 Weight management*

Following weight loss surgery, patients may lose weight fairly rapidly at first, and then as time passes the weight loss becomes more gradual. Commonly, weight will stabilise at about 18 months after RYGB [30]. During these 18 months, weight loss can be erratic with alternating periods of significant weight loss followed by a plateau. Other than the loss of fat mass, there are many other factors that may contribute to the fluctuations in weight loss during the initial phase. This includes variations in water weight which is dependent upon the individuals' hydration status, contents of the gastrointestinal tract, gain of muscle mass, or menstrual cycles [30].

Sustainable weight loss strategies should include tailored exercise programs with monitoring of the exercise frequency and intensity to boost metabolic rate for a more rapid weight loss. A generic exercise program with lack of progressive targeted goals may lead to weight loss plateaus. Increase in physical activity and strength training will cause slower weight loss as the fat is replaced by muscle mass, which are denser tissues. This should not be perceived as a deterrent, but rather a positive trend that will lead to a leaner frame and stronger body. The recommended nutritional plan should be adhered to diligently to ensure adequate nutrition and muscle mass is maintained. Most weight regain or plateaus in weight loss boils down to eating habits. It is recommended that a patient eat several small meals a day with the ultimate goal of eating a regular diet in smaller amounts. Binge eating, snacking or grazing should be avoided as the extra calories will add up to the weight gain.

Several anatomic factors may influence weight loss, and this include the size of the gastric pouch which may change over time with the RYGB. As it enlarges over time, it will accommodate larger meals, causing a reduction in weight loss. Anostomotic dilatation between the stomach pouch and the intestine may also occur and this allows quicker emptying of the pouch, reducing its effect on satiety and potential weight loss [30]. This is also the underlying reason why one should not drink during meals after gastric bypass as it will result in a more rapid transition of solid food from the gastric pouch, eliminating the effect on satiety resulting in ingestion of larger portions. The resultant change in anatomic structure after malabsorptive procedures such as the RYGB also alters the absorption of food with higher absorption of fats, thus reducing the benefit of the surgery [30]. Eating small meals high in protein may help mitigate this effect.

Plateaus and fluctuations in weight loss are to be expected throughout various phases post-surgery. Constant reassurance, providing patient education on the expected outcomes and exploring together the underlying causes of weight plateaus can increase understanding, avoid miscommunication, avert patient depression or frustration with the surgery. A regular exercise regimen and adherence to correct eating behaviour and nutritional intake may lead to greater outcome and a more sustainable long-term weight loss.

#### *4.1.3 Comorbidities*

Frequently, patients undergoing bariatric surgery have associated comorbidities including Type 2 Diabetes Mellitus, cardiovascular disease, lipid abnormalities, fatty liver, degenerative joint disease, hypertension, gastroesophageal reflux disease, and obstructive sleep apnea with considerable impact on disability and quality of life. To reduce the likelihood of weight regain and to ensure that comorbid conditions are adequately managed, all patients should receive careful medical follow-up postoperatively. Monitoring postoperative glycaemic control should consist of achieving glycated HBA1c of 7% or less with fasting blood glucose no greater than 110 mg/dl and postprandial glucose no greater than 180 mg/dl [28]. Lipid abnormalities should be monitored and treated with lipid-lowering therapy that remain above desired goals should be continued. However due to the dramatic reductions in lipid levels, the doses of lipid-lowering drugs should be periodically evaluated [28]. Ideally, a

multidisciplinary team should be in place before the operation is performed. The bariatric surgeon should be part of this comprehensive team that provides pre- and postoperative care. The inclusion of other medical specialties in the team including endocrinologists, gastroenterologists and rehabilitation physicians allow a more holistic approach for the treatment of patients with multiple comorbidities and associated impairments and disabilities.
