THE MOST SUCCESSFUL TREATMENT for extreme obesity is bariatric surgery, which reduces the amount of food a person can eat or digest, leading to significant weight loss. Since 1991, when the National Institutes of Health found that bariatric surgery was the only treatment that had a significant lasting impact on extreme obesity, more people have turned to surgery for weight control. In 2004, over 200,000 weight-loss surgeries were performed. In this article, I'll tell you who can benefit from the surgery, what surgical techniques are used, and how to care for your patient before and after surgery.
Tipping the scales toward obesity
An epidemic in the United States, obesity affects an estimated 30% of American adults. And the epidemic isn't slowing down: The estimated prevalence of obesity has doubled in the past 2 decades.
Obesity, which affects people of all ages, ethnic groups, and socioeconomic backgrounds, harms most body systems, increases the risk of cardiovascular disease and diabetes mellitus, and shortens life expectancy. (See Looking at risks of obesity systematically.) In 2000, weight-related problems ate up approximately 10% of U.S. health care spending.
A patient is considered obese if her body mass index (BMI) is 30 kg/m2 or more. Calculate BMI by dividing her weight (in kilograms) by her height (in meters) squared. Here's how to interpret the results:
- 18.5 to 24.9 kg/m2: normal
- 25 to 29.9 kg/m2: overweight
- 30 to 39.9 kg/m2: obese
- 40 kg/m2 or more: extremely obese.
A person would be considered for surgery if she has a BMI of 40 kg/m2 or above, or a BMI of 35 kg/m2 or above if she has certain weight-related health problems, such as hypertension or severe diabetes. She must be age 18 or older, have been obese for at least 5 years, and have tried but failed at other methods of losing weight. She must also be willing and able to follow through with diet and behavior changes after surgery.
She wouldn't be a candidate if her obesity is caused by a treatable disorder such as hypothyroidism. She may also be excluded if she has a recent history of substance abuse or a major psychiatric disorder.
Surgery weighs in
Bariatric surgery techniques can be classified as either restrictive or malabsorptive. With a restrictive procedure, the surgeon creates a small gastric pouch, which reduces the size of the stomach. When the patient eats, food is digested and absorbed normally, but she eats less because she quickly feels full. In malabsorptive procedures, the surgeon bypasses various lengths of the small bowel, which leads to weight loss because less food is absorbed. For more details, see Get the skinny on bariatric techniques.
Providing specialized nursing care
Most patients scheduled for bariatric surgery return to the surgical unit postoperatively (although some require monitoring in the intensive care unit a few days after surgery). You'll provide the same care any surgical patient requires, including monitoring the airway, maintaining hemodynamic stability, managing pain, providing nutritional support, caring for the wound, and providing education and emotional support.
But bariatric surgery and your patient's obesity will also present some unique challenges. Keep these additional considerations in mind as you prepare your patient for surgery and care for her afterward.
A patient who's extremely obese may have experienced years of discrimination in social and professional settings. She may have suffered psychological, physical, or even sexual abuse. Some patients compensate for past psychological trauma by developing a very strong personality; others have a poor self-image and believe that whatever care or attention they receive is more than they deserve.
Rest assured that your patient is acutely aware that her size makes it hard to care for her. She may believe that those who aren't obese can't possibly understand her problems. With mixed feelings of shame, embarrassment, hope, and fear, she's embarking on a life-altering journey, so be sensitive to her feelings as you provide care.
Tell the patient what to expect after surgery; for example, that she'll awaken with an intravenous (I.V.) catheter, a urinary catheter, and sequential compression stockings. She may also have a nasogastric tube and wound drain.
Also discuss postoperative pain. Besides incisional pain, she may experience referred shoulder pain after laparoscopy from the carbon dioxide used during surgery. Reassure her that her pain will be managed postoperatively so she can comfortably perform deep-breathing and coughing exercises and get out of bed as soon as possible. Teach her to use a 0-to-10 pain assessment scale and, if prescribed, explain how to use a patient-controlled anesthesia device. Explain that she'll receive antiemetics to treat nausea.
Standard hospital beds accommodate patients weighing up to 350 pounds (159 kg). Standard wheelchairs are 18 inches (45 cm) wide and are designed to hold a patient weighing up to 225 pounds (102 kg). Operating and exam tables, beds, stretchers, and wheelchairs that can support obese patients must be available for appropriate perioperative care, and they can be rented if necessary.
You'll also need a supply of oversized gowns and large blood pressure cuffs. Your patient will need a wide, strong bedside chair. She may also have obese visitors who'll need wide armless chairs when visiting.
Cardiac and pulmonary considerations
Because of your patient's obesity, heart sounds may be muffled. To hear them best, get yourself a good stethoscope and keep the room quiet while you listen. You may need to displace excess skin folds to hear heart, lung, or abdominal sounds. If you still can't hear heart sounds, have her lean forward or place her in a left lateral side-lying position.
An extremely obese patient may have obesity hypoventilation syndrome. The fatty tissue pressing on her rib cage prevents maximum expansion of the chest wall, leading to chronic respiratory insufficiency. To prevent atelectasis and pneumonia, teach her deep-breathing and coughing exercises and incentive spirometry. To decrease abdominal pressure on the diaphragm and maximize tidal volume, keep the head of the bed raised to a 30- to 45-degree angle unless contraindicated. If the head of the bed is raised more than 30 degrees, watch for signs of skin breakdown around the sacrum because of increased pressure in that area.
Obstructive sleep apnea, common in patients who are obese, is confirmed with a polysomnography study in a sleep lab. Severe sleep apnea is treated with continuous positive airway pressure (CPAP) or bi-level continuous positive airway pressure (BiPAP). If your patient is being treated for sleep apnea, instruct her to bring CPAP or BiPAP equipment from home to use after surgery.
Fluid balance and vital signs
After surgery, carefully monitor the patient's fluid and electrolyte balance. Monitor her vital signs at least hourly for the first several hours after surgery, then every 4 hours until discharge according to your facility policy. Make sure you have a blood pressure cuff that's large enough to fit her arm.
Watch for signs and symptoms of dehydration and hypovolemia from blood loss or third-space fluid shifts, including persistent tachycardia over baseline, decreased urine output, hypotension, and an increased need for oxygen. Document fluid intake and output and be prepared to give extra fluids to correct hypo volemia, if indicated.
During her recovery, monitor blood chemistries daily, paying particular attention to increased levels of blood urea nitrogen or creatinine and electrolyte imbalances. Remember that the patient's preoperative bowel-cleaning regimen may have depleted her electrolytes.
When your patient switches from I.V. to oral medications, consult an equianalgesic chart to make sure you're giving the correct dose. Keep in mind, however, that obesity can alter the pharmacokinetics of many medications. A pharmacist can help to calculate dosage changes.
Activity and ambulation
After bariatric surgery, a patient is at higher risk for deep vein thrombosis and pulmonary emboli because of stasis from immobility and an increase in red blood cell counts (polycythemia) from chronic respiratory insufficiency. Help her ambulate as soon as possible after surgery and give low-molecular-weight heparin subcutaneously as ordered to help prevent blood clots. Use sequential compression devices whenever she's at rest, whether in a bed or a chair. She may be more comfortable in a foot device than a long-leg device. Foot devices often fit better and also prevent the heat intolerance caused by long-leg devices.
To prevent falls, get extra help when the patient is ready to ambulate. Ideally, you should help her sit on the side of her bed the evening of surgery and walk three or more times a day, starting on the first day after surgery. Physical and occupational therapists can evaluate her readiness for ambulation and activities of daily living.
Skin, wound, and drain-site care
An obese patient is at particular risk for skin breakdown and delayed wound healing. Moisture from perspiration and other body fluids collecting in skin folds, difficulty turning in bed, and equipment that's too small for her can all cause problems. Provide frequent skin care, including daily bathing.
Pressure points over bony prominences can predispose the patient to tissue ischemia and pressure ulcers from immobility. When she's moved in bed, her weight increases friction and shear forces, which can lead to shear injuries.
She's also at risk for atypical pressure ulcers. If she has a large abdominal apron (panniculus), for example, reposition it frequently to prevent pressure injury to underlying abdominal tissue. Tubes and catheters can burrow into skin folds and cause tissue erosion. Whenever you reposition the patient, make sure she's not lying on any tubes or catheters.
Because of your patient's low ratio of skin area to body mass, she perspires excessively. Inspect skin often and keep it clean and dry. Place absorbent material (such as a cotton T-shirt) between the folds of skin, but don't use talcum powder or cornstarch. Use an antifungal powder such as nystatin powder to treat candidal infections (characterized by redness, itching, and maculopapular lesions). As prescribed, apply an antifungal agent for 14 days to eradicate the rash.
Because of the weight of her lower abdomen, the patient may have stress urinary incontinence. She may also have trouble using bedside commodes, bedpans, and bathrooms. A man may have trouble using urinals. Urine on the skin can contribute to skin breakdown. Frequently change linens and use skin sealants or moisture-barrier ointments in perineal skin folds to help prevent problems. But avoid using plastic pads, if possible, because they trap heat and hold moisture next to the skin.
If the patient has an open wound, change the dressing according to the surgeon's instructions. Monitor and document the type, color, and amount of drainage from open wounds and drain tubes.
Because adipose tissue is poorly vascularized, the patient may have delayed healing. Increased body fat creates tension on the wound, which also slows healing. You can use an abdominal binder as a support device for a patient with an open incision. Consult a wound, ostomy, and continence nurse about complex wound or skin problems.
Diet and nutrition
After bariatric surgery, a patient can't take anything by mouth until she's had a Gastrografin upper gastrointestinal series, followed by barium swallow, to rule out anastomotic leaks. This test is usually performed on the first postoperative day. After the test rules out leaks, the patient can start drinking water, then clear liquids, then a full-liquid diet. She'll need to abstain from caffeine and carbonated drinks and to consume only small or moderate amounts of sugar. She'll also need a nutritionally complete protein supplement.
Her new stomach pouch will hold only 15 to 30 ml. Encourage her to drink from a 30-ml medicine cup to help her learn to sip small amounts of fluid frequently.
Surgeons differ in how quickly they advance a patient to a soft diet, but typically a patient remains on a liquid diet for several weeks after surgery. Then she'll advance to a lifelong diet that's high in protein and low in fat and carbohydrates. Her diet generally provides 800 to 1,200 calories/day in four to six small meals. Tell her to expect to have a depressed appetite and to feel full quickly.
The Roux-en-Y gastric bypass procedure and biliopancreatic diversion surgical procedures can lead to deficiencies of iron, calcium, and vitamin B12 because food bypasses the duodenum, where these nutrients are primarily absorbed. Tell the patient she'll need to take a daily multivitamin containing iron and B complex vitamins and calcium supplements to prevent bone demineralization and osteoporosis. She may also need regular B12 supplements, either sublingually or intramuscularly.
Dumping syndrome (rapid gastric emptying), marked by nausea, weakness, sweating, faintness, cramps, and diarrhea for up to 90 minutes after eating, is a common long-term adverse effect of any bariatric surgery. It's believed to be caused by food entering the small intestine rapidly, without partial digestion by gastric enzymes. In general, the more extensive the bypass, the worse the syndrome will be. Patients learn to sidestep this problem by avoiding problem foods or by eating smaller amounts.
All bariatric-surgery patients should have a dietary consult before discharge.
If possible, put the patient in a private room to give her privacy and preserve her dignity. Get a fan for the room to help circulate room air. Because they're stronger, floor-mounted toilets are better than wall-mounted ones.
Before sending the patient to another department for a test or procedure, make sure it has equipment that's large and strong enough and make sure enough staff will be available to assist with patient transfers.
Reinforce postoperative teaching before discharge. Give your patient oral and written instructions about her procedure and postoperative care, emphasizing information about diet progression, vitamin and protein supplements, and adequate hydration. She'll also need general discharge instructions about medications, activity, resumption of driving, wound care, symptoms to report, and follow-up visits. Encourage her to use reliable birth-control methods to prevent pregnancy for the first year after surgery.
Discharge medications should include analgesics and antiemetics. If your patient uses antihypertensives, insulin, or oral antidiabetic medication, her health care provider may need to adjust her dosages before she's discharged.
Remind the patient that she should be as active as possible to maximize her weight loss. Unless contraindicated, she should aim to walk up to 1 mile/day within a few weeks.
Encourage her to attend nutrition classes and psychological counseling sessions. Local support groups can let her network with others sharing similar experiences. Your patient is off to a new and healthier way of life, but she'll need a generous amount of support to stay on track in the years ahead.
Looking at risks of obesity systematically
- Atherosclerotic disease
- Heart failure
- Venous insufficiency
- Obesity hypoventilation syndrome
- Obstructive sleep apnea
- Pulmonary hypertension
- Fatty liver
- Gallbladder disease
- Gastroesophageal reflux disease
- Irritable bowel syndrome
Endocrine system risks
- Menstrual irregularities
- Polycystic ovarian syndrome
- Stress urinary incontinence
- Anxiety disorders
Get the skinny on bariatric techniques
Bariatric procedures can be categorized as restrictive or malabsorptive. Here's a closer look.
Restrictive procedures: Less room for food
The Roux-en-Y gastric bypass procedure (RNYGBP) is the gold standard in North America. It's popular because it's proven to cause long-term weight loss and has excellent patient tolerance and low complication rates.
The RNYGBP works primarily by restriction, although malabsorption contributes a small part to weight loss. This surgery can be performed through an open abdominal incision or laparoscopically. The surgeon divides the stomach with a line of staples, which creates a small gastric pouch (approximately 15 to 30 ml). The jejunum is divided below the ligament of Treitz, the distal limb is brought up, and a gastrojejunostomy is created on the front of the gastric pouch. The proximal limb of the jejunum is anastomosed to the distal jejunum at a measured distance from the gastrojejunostomy. The Roux limb is usually about 40 inches (100 cm) long. The RNYGBP allows food to bypass 90% of the stomach, the duodenum, and a small segment of jejunum.
Vertical-banded gastroplasty (VBG) was for many years the most commonly performed type of restrictive surgery. The surgeon places a vertical line of surgical staples along the lesser curvature of the stomach, creating a small upper stomach pouch of approximately 30 ml, which is anchored distally by a polypropylene band. Food empties into the distal portion of the stomach through the small stoma. Because of the limited capacity of the gastric pouch and narrow gastric outlet, the patient feels full quickly and her gastric emptying is slowed, so she feels satiated and eats less.
The newest restrictive procedure is the Lap-Band System, an adjustable banding system placed laparoscopically. A silicone band placed around the fundus of the stomach creates a small gastric pouch. Within the band's inner lining is an inflatable balloon that's connected to a subcutaneous port tunneled from the band to subcutaneous tissue on the patient's abdomen. The band can be inflated or deflated, adjusting the stoma size as needed. The Lap-Band can be modified or reversed. Higher-risk patients may benefit from this less-invasive approach.
Malabsorptive surgery: Taking the bypass route
The most common malabsorptive procedure, shown below, is the biliopancreatic diversion (BPD), which is transection of the stomach with anastomosis of the duodenum to the distal ileum. Pancreatic enzymes and bile enter the ileum near the distal ileum, letting nutrients pass from the stomach to the distal ileum without being digested. The patient loses weight because of a partial gastrectomy that restricts intake and a shortened alimentary channel, which causes malabsorption. The patient can lose up to 70% of her excess weight and maintain the loss over the long term.
A variation of the BPD procedure reduces the risk of having bile reflux. The procedure includes a “duodenal switch,” which leaves a larger portion of the stomach intact, including the pyloric valve, and it also keeps a small part of the duodenum in the digestive pathway. Preserving the pyloric valve helps prevent dumping syndrome.
Hilary S. Blackwood is a clinical nurse practitioner at the Duke Weight Loss Surgery Center, Duke University Medical Center, in Durham, N.C. This article has been updated and adapted from “Obesity: A rapidly expanding challenge,” Nursing Management, May 2004.
The author has disclosed that she has no significant relationships with or financial interest in any commercial companies that pertain to this educational activity.