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Surgery for Morbid Obesity
AORN JOURNAL
MAY 1990, VOL. 51, NO 5
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Surgery for Morbid Obesity USING AN INFLATABLE GASTRICBAND
Lubomyr I. Kuzmak, MD; Ida S. Yap, RN; Lisa McGuire, RN; Joyce S . Dixon, RN; Myrna P. Young, RN ne of every five adult Americans is overweight, and, as a population, adult Americans carry more than 2.3 billion pounds of excess weight.' Of those who are overweight, one third qualify as morbidly obese: meaning their weight is 100 or more pounds over the ideal weight as recommended by the Metropolitan Life Insurance Company. Excess body fat accumulation occurs when the energy intake is greater than the energy expenditure. Environmental and genetic factors contribute to this imbalance along with metabolic and endocrine abnormalities. The availability of food combined with sedentary life-styles also may contribute to the obesity problem in America.
0
Many health problems arle associated with obesity, which shortens a person's life expectancy by 10 to 15 years and creates enormous psychological burdens. Obesity may increase the incidence of cardiovascular dislease, hypertension, and diabetes.3 Severely obese people tend to develop severe arthritis of the slpine and legs! The incidence of breast, endometrial, colon, and prostrate cancer is higher in obese p e ~ p l e . ~ Morbid obesity must be treated to prevent serious health problems. Dietiing combined with exercise and behavior modification is the safest method for weight reduction. L,ong term statistics, however, show that dieting has a failure rate close to 100%in the morbidly obese.6
Lubomyr I. Kuzmak, MD, ScD, Is a general and vascular surgeon in private practice in Livingston, NJ. He received his doctorate of medicine from the Medical Academy, Lodz, Poland, and his doctorate in science from the Silesian Academy of Medicine, Bytom, Poland.
Joyce S. Dixon, RN, BA, is a charge nurse, surgical unit, Irvington (NJ) Ge,rzeralHospital. She received her nursing diploma ffism Lyons Institute, Newark, NJ, and her bachelor. of arts degree in community health from Jersey City (NJ) State College.
Ida S. Yap, RN, BSN is a patient care coordinator, surgical and telemetry units, Irvington (NJ) General Hospital. She received her bachelor of science degree in nursing from Angeles University, A ngeles City, Philippines.
Myrna P. Young, W, MS, is the director of patient care for the operating room, short stay unit, recovery room, and emergency room, Irvington (NJ) General Hospital. She received her nursing diploma from the Marian School of Nursing, Manila, Philippines, her bachelor of science degree in nursing from the Far Eastern University, Manila, and her .master of science degree in nursing administrationfrom Seton Hall University, South Orange, NJ.
Lisa McGuire, RN, BSN, is a patient care coordinator, surgical services department, Irvington (NJ) General Hospital, She received her BSN from Seton Hall University, South Orange, NJ.
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Fig 1. The intestinal bypass. A short intestinal tract is created that bypasses most of the small intestine. The bypassed portion of the small intestine forms a blind loop. (All illustrations courtesy of Thomas Wenzel, Iowa Ci,ty)
To be effective in long-term weight loss, a method must have a permanent effect on the obese person. The high rate of failure in dieting and other weight-loss methods for controlling severe obesity led to the development of surgical procedures.
History of Surgical A lternatives
I
n general, surgeries for morbid obesity are divided into two groups: those that cause malabsorption (ie, shortening the common passage of food and digestive juices) and those that cause gastric restriction (ie, reducing the stomach size). The intestinal bypass, a procedure that results in malabsorption, was introduced in the 1950s
as the first surgery for controlling severe obesity? The surgeon divides the jejunum and connects the proximal segment to the terminal ileum to create a short intestinal tract that bypasses most of the small intestine (Fig 1). Thie bypassed portion of the small intestine forms a sort of “blind loop.” Modifications were tried in the intestinal bypass, mainly by changing the length of the functioning jejunum or ileum. Although patients lost considerable amounts of weight, the long-term follow-up showed severe and sometimes fatal complications.8 It is no longer performed in the United States. At present, the only accepted malabsorption surgery is the biliopancreatic d i ~ e r s i o nIn . ~contrast to the intestinal bypass, there is no blind loop or short loop of the small intestine, which is the source of serious complications with the intestinal 1309
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MAY 1990, VOL. 51, NO 5
Fig 2. The biliopancreaticdiversion. Food passage is separated from the digestive juices until it reaches the final segment of the terminal ileum. bypass. Instead, malabsorption is achieved by separating the food passage from the digestive juices until it reaches the 50-cm segment of the terminal ileum (Fig 2). To date, this surgery has not created the complications observed with an intestinal bypass. The advantage of this malabsorption surgery is that patients maintain normal eating habits with predictable weight loss. The surgery, however, is an extensive procedure that requires a partial gastrectomy and cholecystectomy in addition to the intestinal anastomosis. In 1966, gastric restriction surgery was introduced to reduce food intake.1° The surgeon 1310
forms a small pouch and a small opening (ie, stoma) that connects the pouch with the gastrointestinal tract. Initially, weight loss was minimal. By limiting the gastric pouch size and the stoma diameter, later surgeries significantly improved weight loss." In the first gastric bypasses, the stomach was divided to form a small pouch.I2Later, the stomach was partitioned with ~tap1es.l~Gastric bypass surgery still is performed although the Roux en Y gastric bypass is the most common (Fig 3).14 Gastric bypass surgery started the evolution of gastric restriction surgeries. In 1976, horizontal gastroplasty was reintroduced (Fig 4).'5 In
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Fig 3. Roux en Y gastric bypass. Stomach is divided to form a small pouch. horizontal gastroplasty, the food passage is not changed as it is in a gastric bypass. Also, the surgeon can inspect the distal stomach and the duodenum with a gastroscope. With a gastric bypass, such inspection is impossible. In the long term, however, the failure rate from staple disruption and stoma dilation was so high that horizontal gastroplasty was abandoned.16 In 1979, vertical stapling gastroplasty was introduced.l7 Initially, the stoma was reinforced with sutures, but stoma dilation caused a high failure rate. To solve the problem, some surgeons sutured a silicone tubing over the stoma to create a lesser curvature, a technique still in use.18 1312
In 1980, vertical-banded gastroplasty, a modification of vertical-stapling gastroplasty, was introduced (Fig 5).19 In this surgery, the surgeon forms a small pouch with four vertical rows of staples and reinforces the stoma with a 1.5-cm wide strip of polypropylene mesh.
Gastric Banding
G
astric banding was introduced in 1980.*O Because most of the materials used for gastric banding caused severe tissue reactions and adhesions, Lubomyr I. Kuzmak, MD (the senior author), began using a DacronTM
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Fig 4. Horizontal gastroplasty. The stomach is partitioned, but the food passage is not chLanged as it is in a gastric bypass. The surgery has a high failure rate because of stoma dilation and staple disruption.
Fig 5. Vertical-banded gastroplasty. A small pouch is formed with four vertical rows of staples. Stoma is reinforced with a strip of polypropylene mesh. 1313
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Fig 6. Gastric banding. A small pouch and a reinforced stoma are created in one step by placing and tightening the silicone gastric band around the stomach.
reinforced silicone band made to his specifications. Silicone is one of the most inert materials used in the medical field. Gastric banding is the least extensive surgery performed to control morbid obesity. The stomach is not cut or crushed by staples, no anastomoses are made, and the food passage is not changed. Instead, a small pouch and a reinforced stoma are created in one step by placing and tightening the band around the stomach (Fig 6 ) . To create a desirable stoma diameter and pouch capacity, Dr Kuzmak designed a calibrating tube with an electronic sensor to determine the stoma diameter (Fig 7). Pouch capacity is measured with an inflatable balloon. The stoma diameter is a crucial part of any gastric restriction surgery. Enlarging the stoma 1314
diameter by 1 to 2 mm will affect weight loss; restricting the diameter will cause excessive vomiting. Even with a properly calibrated and reinforced stoma, some individuals will be able to eat more than others. To individually tailor the stoma diameter and pouch size without additional surgery, Dr Kuzmak modified the original silicone band by adding a 4-cm inflatable balloon to it. The balloon is connected to a self-sealing reservoir by a thin silicone tube (Fig 8). The band is partially preinflated during surgery. Postoperatively, if there is excessive vomiting or any medical condition that requires better nutrition, the surgeon can enlarge the stoma diameter by withdrawing the saline solution via a spinal needle inserted percutaneously into the
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Fig Z Pouch and stoma calibrating tube designed by Dr Kuzmak.
Fig 8. Inflatable silicone band, nonkinking silicone tube, and self-sealing reservoir connected to gastric band. Stoma diameter and pouch size can be adjusted by adding or withdrawing fluid. reservoir. Conversely, additional saline can be injected into the reservoir to decrease the stoma diameter. Stoma adjustments are done on an outpatient basis. The modified band (ie, an inflatable silicone gastric band as opposed to a noninflatable silicone band) has improved postoperative weight loss and has given surgeons more control over patients. Since 1983, 173 noninflatable silicone gastric bands have been inserted in patients at Irvington
(NJ) General Hospital: 125 primary surgeries and 48 revisions of other gastric restriction surgeries. Since June 1986, 100 inflatable silicone gastric bands have been inserted: 68, primary surgeries and 32 revisions of other gastric surgeries. Table 1 shows that the percent of excess weight loss after two years with the inflatable silicone gastric bands are comparable to that produced by either the vertical-banded gastroplasty or a Roux en Y gastric bypass.*' 1315
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Table 1
A Comparison of Excess Weight Loss Noninflatable silicone gastric bands Inflatable silicone gastric bands Vertical banded gastroplast
I
Roux en Y gastric bypass
0
10
20
30
40
50
60
70
Percent excess weight loss after two years
Candidate Selection
C
andidates for gastric banding surgery are carefully evaluated. Guidelines for selection include patients 100lbs or more above the ideal weight for height, or if the patient weighs less, serious medical obesity related conditions known to be ameliorated by weight loss must be present.22The acceptable age range is 18 to 50 years. Potential candidates are sent a booklet containing general information about the surgery and an extensive questionnaire pertaining to their obesity and medical history. They are asked to return the questionnaire and contact the office for an appointment. It is our office policy not to call prospective candidates until they make the initial contact. Two office visits are required. The first visit is scheduled with the patient care coordinator who asks the patient detailed questions about his or her medical and psychological background. The
coordinator gives the patient a second booklet with several articles about surgery for obesity and silicone gastric banding. Information about surgical risks, postoperative life-style changes, and a copy of the postgastric banding diet also is included. During the second visit, the candidate views a videotape presentation on the surgical risks and how the surgery will change eating habits and life-style. After the videotape, the surgeon explains the silicone gastric banding surgery, the long-term results, and the possible postoperative complications and surgical risks. The dietitian stresses the changes in eating habits. Before the patient enters the hospital, a gastrointestinal series and an ultrasound of the gallbladder are done. Contraindications include an active peptic ulcer, a large hiatus hernia, or a malignancy of the stomach. When gallstones are found, a cholecystectoniy may be done simuftaneously with the inflatable silicone gastric banding surgery. Intraoperative cholangiogram or 1317
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common bile duct exploration should not be done because of potential infection around the band.
Patient Preparation
A
t Irvington General Hospital, care of the morbidly obese patient is based on a teamwork approach among the medicalsurgical unit nurses, the OR nurses, dietitians, and specialists from the anesthesiology, pulmonary medicine, gastroenterology, and internal medicine/cardiology departments. Members of the consulting medical team should be well informed about the type of surgery and the potential complications. They also should be aware of changes in the patient’s eating patterns after the surgery so that the prescribed medications and diet will be tolerated. The medical-surgical unit needs rooms prepared for severely obese patients with special beds, toilet bowls, wheelchairs, gowns, and blood pressure cuffs designed for morbidly obese patients. After admission to the surgical floor, the patient undergoes routine preoperative tests including complete blood count, serum chemistries, a urinalysis, an electrocardiogram, and a chest xray. Baseline arterial blood gases are obtained on all patients because common complications from major surgery in obese patients are pulmonary congestion, atelectasis, and/or pneumonia. Pulmonary consultation is obtained for all patients. For patients with known cardiovascular problems, a cardiac consultation is requested. A pregnancy test is ordered for females unless they have had a hysterectomy. Height and weight are recorded. The physician is notified of any abnormalities. The patient is started on a full-liquid diet. A nurse also completes an assessment and history with emphasis on the patient’s dietary habits and psychosocial background. As the nurse establishes rapport with the patient, he or she assesses the patient’s knowledge and expectations of the surgery and gives the patient an opportunity to express feelings. Informing patients of what to expect in pre- and postoperative instruction will help alleviate some of the anxiety that accompanies any surgical procedure.
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The nurse instructs the patient in deep breathing and leg exercises as well as turning side to side every two hours postoperatively. An overhead trapeze is mounted to help the patient with postoperative turning. A respiratory technician shows the patient how to use the spirometer. The night before surgery, the patient’s abdomen is shaved and he or she receives a subcutaneous injection of heparin and a sleeping medication, if desired. The patient also receives an enema. Patients are NPO after midnight.
Preoperative Care
T
he morning of surgery, the nurse completes the preoperative checkliist and administers an antibiotic injection and another dose of heparin. Any preoperative medication is given as ordered by the anesthesiologist. The patient is transported to the OR holding area. The OR nurse greets the patient and verifies his or her identification. The anesthesiologist inserts the intravenous (IV) line and begins IV therapy with 5% dextrose in half-normal saline with 20 mEq potassium chloride. The circulating and scrub nurses set up the operating room according to the surgeon’s preference card. Instruments include a major basic set, gastric banding set, additional long instruments, vessel clips, and the modified Gomez retractor. The banding set consists of a kidney pedicle clamp, stomach clamp, hook, two Hegar dilators, four tonsil clamps, a long plain forcep, long Metzenbaum scissors, two mosquito clamps, and the banding instrument, which tightens the band around the stomach and holds it until the band is sutured. Additional long instruments include a knife handle, clamps, and scissors. Sutures used are in accordance with the preference card. A 3-mL syringe with an 18-gauge intravenous catheter is filled with steriile saline to irrigate and partially inflate the band. The gastric band is soaked in a neomycin solution. The scrub nurse sets up the sterile saline for inflating the band in a separate medicine cup. After the setup is finished, the circulating and scrub nurses make the first count of the instruments and sponges, needles, and sharps. The nurses 1319
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Fig 9. Inflatable silicone gastric band placed around the stomach.
complete three counts of sponges, needles, sharps, and instruments-one preoperatively, one when the peritoneum is closed, and one when the skin is closed. The circulating nurse then brings in the patient and helps move him or her to the OR bed. The OR bed is put in reverse Trendelenburg position which shifts the weight off the patient’s chest to help him or her breathe while awake. This position also provides the surgeon better visualization of the surgical site. The arm boards are attached to the table and positioned. Compression antiembolic stockings are placed on the patient’s legs and connected to the pump, which is then turned on. Blood pressure and heart rate are measured. Pulse oximetry is measured by placing a device on the patient’s fingertip that determines oxygen saturation with infrared light. The nurse explains to the patient what is being done to allay fear and decrease anxiety. 1320
After the patient has been anesthetized, the circulating nurse inserts the Foley catheter and applies the electrosurgical dispersive pad. The circulating nurse then scrubs the abdomen with povidone-iodine and pats it dry with sterile towels provided by the scrub nurse. After the surgeon and assistant are gowned and gloved, they finish prepping and draping.
Surgery
T
he surgery begins with the surgeon making an upper midline incision and dissecting subcutaneous fat from the right anterior rectus sheath. A small part of the sheath and a small part of the right rectus muscle are cut with the electrocautery knife to prepare a space for the self-sealing reservoir. The surgeon then opens the abdomen. A modified Gomez retractor is assembled to
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Fig 10. Banding instrument tightens and holds the band while the surgeon calibrates the stoma and stomach pouch. obtain good exposure of the surgical site. The surgeon opens the avascular portion of the hepatogastric ligament and, by blunt dissection with fingers, makes a tunnel under the stomach and through the suspensory ligament of the fundus proximal to the short gastric vessels. A Penrose drain is placed through the opening and wound around the stomach. A small opening is made next to the lesser curvature of the stomach, approximately 2 cm below the gastroesophageal junction and medial to the gastric vessels and vagus nerve. The surgeon irrigates the tube and balloon of the inflatable silicone gastric band to remove any air. The balloon is preinflated with 0.8 mL of saline solution. The surgeon then threads the band through the opening next to the lesser curvature and around the stomach (Fig 9) and removes the Penrose drain. 1322
After the anesthesiologist inserts the pouch and stoma calibrating tube through the mouth and into the stomach, the surgeon tightens the band with the banding instrument (Fig 10). When the pouch and stoma have been calibrated, the surgeon sutures the band together and excises the buckle and any extra part of the band. He or she places the tube connected to the inflatable balloon under the diaphragm and into the space prepared within the right rectus sheath. The self-sealing reservoir then is filled with the saline solution and connected to the silicone tube. All incisions are closed in the usual fashion. During surgery, the circulating nurse helps the anesthesiologist and keeps accurate records of any added sponges, needles, sharps, or other equipment. Because of the amount of fatty tissue on very obese patients, items could be misplaced. The scrub nurse tries to anticipate the needs
MAY 1990, VOL. 51, NO 5
of the surgeon and monitor instrument and sponge locations. Laparotomy rings are always used with laparotomy sponges. Using a magnetic mat helps keep the field neat and prevents the instruments from sliding. The scrub nurse must secure any specimens. The circulating nurse labels and records all specimens in the logbook. After the wound is closed, the area is cleaned and covered with narrow strips of nonadhesive dressing. The surgeon places transcutaneous electrical nerve stimulation electrodes on opposite sides of the suture line to alleviate postoperative pain. An abdominal binder is placed in some patients. The scrub nurse clears away the instruments, and the circulating nurse stays with the patient and anesthesiologist to prepare the patient for transfer to the postanesthesia care unit (PACU). The circulating nurse records urine output and IV intake. The electrosurgical dispersive pad site is checked and the skin condition recorded. Documentation is essential for the surgical procedure. Both the scrub and circulating nurses sign the nursing operative record and instrument sheets. The label of the band is attached to the chart for record keeping. Before transferring the patient to the PACU, the circulating nurse informs the PACU nurses. He or she gives them a verbal report that includes the name of the patient, the surgeon, the anesthesiologist, the type of procedure, drains, types of anesthesia, intake and output, allergies, medical problems, antibiotic or blood products given, and any problems encountered during the surgery. The patient is transported to the PACU by the hospital attendant, the circulating nurse, and the anesthesiologist. The head of the bed is raised before transporting. The patient receives oxygen through a nasal cannula during transport.
Postoperative Care
W
hen the patient arrives in the PACU, the nurses assess and record his or her airway patency and vital signs. The patient is given oxygen by mask as ordered.
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The patient is encouraged to take deep breaths, move feet, and bend knees. F’atients are helped with turning if they request a position change. The head of the bed is kept elevated to make the patient more comfortable and enhance breathing. Nurses administer pain medications, record intake and output, and check the wound dressing. Compression antiemblolic stockings stay in place. Arterial blood gases ;ire checked on all patients who weigh more than 300 pounds or who have histories of asthma or chronic obstructive pulmonary disease. Nurses give the patient emotional support and reassurance throughout his or her stay in the PACU. A scoring system is used as a guide for discharging the patient from the PACU, normally in two to three hours. When tlhe patient is ready for transfer to the surgical unit, the nurses are notified and informed of any special needs, such as oxygen. Most patients go directly to the medicalsurgical unit from the PACU. The surgeon and anesthesiologist decide if the patient requires intensive care. After the patient is returned to the medicalsurgical unit, the nurse assess him or her for respiratory distress, vital signs, body temperature, signs of pain, bleeding, circulatory impairment, and body alignment. No nasogastric tube is inserted in a patient with a gastric band. The patient is allowed to take sips of water. The patient is instructed to take 10 to 15 deep breaths per hour and to exercise his or her legs and arms. Extra pillows are used to splint the abdomen when deep breaths are taken. Patients receive oxygen through a nasal cannula for 24 to 48 hours postoperatively. Antibiotics and heparin administration is continued. Pain medication is given, as neelded, to alleviate postoperative pain and provide comfort. On the second postoperative day, antibiotics and IV therapy are discontinued and the Foley catheter is removed. The postgastric banding diet is started and progressed daily. The patient is instructed to eat slowly, chew wdl, and stop eating when full. Small straws are used to sip beverages to reduce swallowed air. Independent inspiratory spirometry is continued. The patient walks with assistance. 1323
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By the seventh or eighth postoperative day, the patient is discharged. Before discharge, the surgeon removes the sutures and gives discharge instructions describing activities,diet, and follow-up visits. The nurse and dietitian reinforce the instructions. The dietitian gives the patient copies of a diet to follow. The patient then is weighed to determine weight loss during the hospital stay. The importance of office follow-up visits is stressed. Local patients are encouraged to visit monthly. Patients are not charged for postoperative visits. Out-of-state patients correspond through questionnaires mailed to the physician every three months. After discharge, the patients must begin changing life-style and eating habits because the success of the surgery depends on them. 0 Notes 1. B M Hannon, T G Lohman, “The energy cost of overweight in the United States,” American Journal of Public Health 68 (August 1978) 765-767. 2. Health Implications of Obesity (Bethesda, MD: National Institutes of Health Concensus Development Conference Statements, February, 1985). 3. P Berchtold et al, “Cardiovascular risk factors in gross obesity,” Infernational Journal of Obesiw 1 (March 1977) 219. 4. Health Implications of Obesity. 5. Ibid. 6. Ibid. 7. A N Kremen, J H Linner, C H Nelson, “Experimental evaluation of the nutritional importance of proximal and distal intestine,” Annals of Surgery (September 1954) 439-444; J H Payne, L T DeWind, R R Commons, “Metabolic observations in patients with jejunocolic shunts,” American Journal of Surgeiy 106 (July 1963) 273-289. 8. H W Scott, Jr et al, “Jejunoileal shunt in surgical treatment of morbid obesity,” Annals of Surgery 171 (May 1970) 770-782. 9. N Scopinaro et al, “Two years of clinical experience with biliopancreatic bypass for obesity,” American Journal of Clinical Nutrition 33 (February 1980) 506-514. 10. E E Mason, C Ito, “Gastric bypass in obesity,” Surgery Clinics ofNorth America 47 (December 1967) 1345-135 1. 11. E E Mason et al, “Gastric bypass for obesity after ten years experience,” International Journal of Obesity 2 no 2 (1978) 197-206. 12. Zbid; Mason, Ito, “Gastric bypass in obesity,” 1345-1351. 13. J F Alden, “Gastric and jejunoileal bypass: A comparison in the treatment of morbid obesity,” 1324
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Archives ofsurgery 112 (July 1977) 799-806. 14. W 0 Griffen, Jr, V L Young, C C Stevenson, “A prospective comparison of gastric and jejunoileal bypass procedures for morbid obesity,” Annals of Surgery 186 (October 1977) 500-509; E E Mason et al, “Gastric bypass in morbid obesity,” American Journal of Clinical Nutrition 33 (February 1980) 395405. 15. C A Gomez, “Gastroplasty in morbid obesity,” Surgery Clinics of North America 59 (December 1979) 1113-1120. 16. J B Freeman, H Burchett, “Failure rate with gastric partitioning for morbid obesity,” American Journal of Surgery 145 (January 1983) 113-119. 17. H L Laws, “Standardized gastroplasty orifice,” American Journal of Surgery 141 (March 1981) 393394. 18. G V Eckhout, J F Prinzing, “Surgery for morbid obesity: Comparison of gastric bypass with vertically stapled gastroplasty,” Colorado Medicine 78 (April 1981) 117-122; J P OLeary, “Partition of the lesser curvature of the stomach in morbid obesity,” Surgery, Gynecology & Obstetrics 154 (January 1982) 85-86; G V Eckhout, “Long-term results of vertical gastroplasty with chromic or Silastic ring supported gastric stomach vs gastric bypass for treatment of morbid obesity,” presented at the First Annual Meeting of the American Society of Bariatric Surgery, Iowa City, Iowa, June 1984. 19. E E Mason, “Vertical banded gastroplasty for obesity,” Archives of Surgery 117 (May 1982) 701706. 20. K Kolle, “Gastric banding,” presentation at the OMGI Seventh Congress, Stockholm. Abstract 145:37; 0 Bo, 0 Modalsli, “Gastric banding, a surgical method of treating morbid obesity: Preliminary report,” International Journal of Obesiw 7 no 5 (1983) 493499, M Molina, H Oria, “Gastric banding,” presentation at the Sixth Annual Bariatric Surgery Colloquium, Iowa City, Iowa, June 1983. 21. J B Holt, C L Castiglione, P E Trowbridge, ‘‘Immediate and long-term results of vertical banded gastroplasty for morbid obesity,” Connecticut Medicine 51 (October 1987) 638-642; H J Sugerman et al, “Weight loss with vertical banded gastroplasty and Roux-Y gastric bypass for morbid obesity with selective versus random assignment,” American Journal of Surgery 157 (January 1989) 93-102. 22. Guidelinesfor Selection of Patients for Surgical Treatment of Obesiw (San Francisco: The American Society for Bariatric Surgery, 1986).
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Surgery for Morbid Obesity USING AN INFLATABLE GASTRICBAND
Lubomyr I. Kuzmak, MD; Ida S. Yap, RN; Lisa McGuire, RN; Joyce S . Dixon, RN; Myrna P. Young, RN ne of every five adult Americans is overweight, and, as a population, adult Americans carry more than 2.3 billion pounds of excess weight.' Of those who are overweight, one third qualify as morbidly obese: meaning their weight is 100 or more pounds over the ideal weight as recommended by the Metropolitan Life Insurance Company. Excess body fat accumulation occurs when the energy intake is greater than the energy expenditure. Environmental and genetic factors contribute to this imbalance along with metabolic and endocrine abnormalities. The availability of food combined with sedentary life-styles also may contribute to the obesity problem in America.
0
Many health problems arle associated with obesity, which shortens a person's life expectancy by 10 to 15 years and creates enormous psychological burdens. Obesity may increase the incidence of cardiovascular dislease, hypertension, and diabetes.3 Severely obese people tend to develop severe arthritis of the slpine and legs! The incidence of breast, endometrial, colon, and prostrate cancer is higher in obese p e ~ p l e . ~ Morbid obesity must be treated to prevent serious health problems. Dietiing combined with exercise and behavior modification is the safest method for weight reduction. L,ong term statistics, however, show that dieting has a failure rate close to 100%in the morbidly obese.6
Lubomyr I. Kuzmak, MD, ScD, Is a general and vascular surgeon in private practice in Livingston, NJ. He received his doctorate of medicine from the Medical Academy, Lodz, Poland, and his doctorate in science from the Silesian Academy of Medicine, Bytom, Poland.
Joyce S. Dixon, RN, BA, is a charge nurse, surgical unit, Irvington (NJ) Ge,rzeralHospital. She received her nursing diploma ffism Lyons Institute, Newark, NJ, and her bachelor. of arts degree in community health from Jersey City (NJ) State College.
Ida S. Yap, RN, BSN is a patient care coordinator, surgical and telemetry units, Irvington (NJ) General Hospital. She received her bachelor of science degree in nursing from Angeles University, A ngeles City, Philippines.
Myrna P. Young, W, MS, is the director of patient care for the operating room, short stay unit, recovery room, and emergency room, Irvington (NJ) General Hospital. She received her nursing diploma from the Marian School of Nursing, Manila, Philippines, her bachelor of science degree in nursing from the Far Eastern University, Manila, and her .master of science degree in nursing administrationfrom Seton Hall University, South Orange, NJ.
Lisa McGuire, RN, BSN, is a patient care coordinator, surgical services department, Irvington (NJ) General Hospital, She received her BSN from Seton Hall University, South Orange, NJ.
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Fig 1. The intestinal bypass. A short intestinal tract is created that bypasses most of the small intestine. The bypassed portion of the small intestine forms a blind loop. (All illustrations courtesy of Thomas Wenzel, Iowa Ci,ty)
To be effective in long-term weight loss, a method must have a permanent effect on the obese person. The high rate of failure in dieting and other weight-loss methods for controlling severe obesity led to the development of surgical procedures.
History of Surgical A lternatives
I
n general, surgeries for morbid obesity are divided into two groups: those that cause malabsorption (ie, shortening the common passage of food and digestive juices) and those that cause gastric restriction (ie, reducing the stomach size). The intestinal bypass, a procedure that results in malabsorption, was introduced in the 1950s
as the first surgery for controlling severe obesity? The surgeon divides the jejunum and connects the proximal segment to the terminal ileum to create a short intestinal tract that bypasses most of the small intestine (Fig 1). Thie bypassed portion of the small intestine forms a sort of “blind loop.” Modifications were tried in the intestinal bypass, mainly by changing the length of the functioning jejunum or ileum. Although patients lost considerable amounts of weight, the long-term follow-up showed severe and sometimes fatal complications.8 It is no longer performed in the United States. At present, the only accepted malabsorption surgery is the biliopancreatic d i ~ e r s i o nIn . ~contrast to the intestinal bypass, there is no blind loop or short loop of the small intestine, which is the source of serious complications with the intestinal 1309
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Fig 2. The biliopancreaticdiversion. Food passage is separated from the digestive juices until it reaches the final segment of the terminal ileum. bypass. Instead, malabsorption is achieved by separating the food passage from the digestive juices until it reaches the 50-cm segment of the terminal ileum (Fig 2). To date, this surgery has not created the complications observed with an intestinal bypass. The advantage of this malabsorption surgery is that patients maintain normal eating habits with predictable weight loss. The surgery, however, is an extensive procedure that requires a partial gastrectomy and cholecystectomy in addition to the intestinal anastomosis. In 1966, gastric restriction surgery was introduced to reduce food intake.1° The surgeon 1310
forms a small pouch and a small opening (ie, stoma) that connects the pouch with the gastrointestinal tract. Initially, weight loss was minimal. By limiting the gastric pouch size and the stoma diameter, later surgeries significantly improved weight loss." In the first gastric bypasses, the stomach was divided to form a small pouch.I2Later, the stomach was partitioned with ~tap1es.l~Gastric bypass surgery still is performed although the Roux en Y gastric bypass is the most common (Fig 3).14 Gastric bypass surgery started the evolution of gastric restriction surgeries. In 1976, horizontal gastroplasty was reintroduced (Fig 4).'5 In
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Fig 3. Roux en Y gastric bypass. Stomach is divided to form a small pouch. horizontal gastroplasty, the food passage is not changed as it is in a gastric bypass. Also, the surgeon can inspect the distal stomach and the duodenum with a gastroscope. With a gastric bypass, such inspection is impossible. In the long term, however, the failure rate from staple disruption and stoma dilation was so high that horizontal gastroplasty was abandoned.16 In 1979, vertical stapling gastroplasty was introduced.l7 Initially, the stoma was reinforced with sutures, but stoma dilation caused a high failure rate. To solve the problem, some surgeons sutured a silicone tubing over the stoma to create a lesser curvature, a technique still in use.18 1312
In 1980, vertical-banded gastroplasty, a modification of vertical-stapling gastroplasty, was introduced (Fig 5).19 In this surgery, the surgeon forms a small pouch with four vertical rows of staples and reinforces the stoma with a 1.5-cm wide strip of polypropylene mesh.
Gastric Banding
G
astric banding was introduced in 1980.*O Because most of the materials used for gastric banding caused severe tissue reactions and adhesions, Lubomyr I. Kuzmak, MD (the senior author), began using a DacronTM
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Fig 4. Horizontal gastroplasty. The stomach is partitioned, but the food passage is not chLanged as it is in a gastric bypass. The surgery has a high failure rate because of stoma dilation and staple disruption.
Fig 5. Vertical-banded gastroplasty. A small pouch is formed with four vertical rows of staples. Stoma is reinforced with a strip of polypropylene mesh. 1313
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Fig 6. Gastric banding. A small pouch and a reinforced stoma are created in one step by placing and tightening the silicone gastric band around the stomach.
reinforced silicone band made to his specifications. Silicone is one of the most inert materials used in the medical field. Gastric banding is the least extensive surgery performed to control morbid obesity. The stomach is not cut or crushed by staples, no anastomoses are made, and the food passage is not changed. Instead, a small pouch and a reinforced stoma are created in one step by placing and tightening the band around the stomach (Fig 6 ) . To create a desirable stoma diameter and pouch capacity, Dr Kuzmak designed a calibrating tube with an electronic sensor to determine the stoma diameter (Fig 7). Pouch capacity is measured with an inflatable balloon. The stoma diameter is a crucial part of any gastric restriction surgery. Enlarging the stoma 1314
diameter by 1 to 2 mm will affect weight loss; restricting the diameter will cause excessive vomiting. Even with a properly calibrated and reinforced stoma, some individuals will be able to eat more than others. To individually tailor the stoma diameter and pouch size without additional surgery, Dr Kuzmak modified the original silicone band by adding a 4-cm inflatable balloon to it. The balloon is connected to a self-sealing reservoir by a thin silicone tube (Fig 8). The band is partially preinflated during surgery. Postoperatively, if there is excessive vomiting or any medical condition that requires better nutrition, the surgeon can enlarge the stoma diameter by withdrawing the saline solution via a spinal needle inserted percutaneously into the
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Fig Z Pouch and stoma calibrating tube designed by Dr Kuzmak.
Fig 8. Inflatable silicone band, nonkinking silicone tube, and self-sealing reservoir connected to gastric band. Stoma diameter and pouch size can be adjusted by adding or withdrawing fluid. reservoir. Conversely, additional saline can be injected into the reservoir to decrease the stoma diameter. Stoma adjustments are done on an outpatient basis. The modified band (ie, an inflatable silicone gastric band as opposed to a noninflatable silicone band) has improved postoperative weight loss and has given surgeons more control over patients. Since 1983, 173 noninflatable silicone gastric bands have been inserted in patients at Irvington
(NJ) General Hospital: 125 primary surgeries and 48 revisions of other gastric restriction surgeries. Since June 1986, 100 inflatable silicone gastric bands have been inserted: 68, primary surgeries and 32 revisions of other gastric surgeries. Table 1 shows that the percent of excess weight loss after two years with the inflatable silicone gastric bands are comparable to that produced by either the vertical-banded gastroplasty or a Roux en Y gastric bypass.*' 1315
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Table 1
A Comparison of Excess Weight Loss Noninflatable silicone gastric bands Inflatable silicone gastric bands Vertical banded gastroplast
I
Roux en Y gastric bypass
0
10
20
30
40
50
60
70
Percent excess weight loss after two years
Candidate Selection
C
andidates for gastric banding surgery are carefully evaluated. Guidelines for selection include patients 100lbs or more above the ideal weight for height, or if the patient weighs less, serious medical obesity related conditions known to be ameliorated by weight loss must be present.22The acceptable age range is 18 to 50 years. Potential candidates are sent a booklet containing general information about the surgery and an extensive questionnaire pertaining to their obesity and medical history. They are asked to return the questionnaire and contact the office for an appointment. It is our office policy not to call prospective candidates until they make the initial contact. Two office visits are required. The first visit is scheduled with the patient care coordinator who asks the patient detailed questions about his or her medical and psychological background. The
coordinator gives the patient a second booklet with several articles about surgery for obesity and silicone gastric banding. Information about surgical risks, postoperative life-style changes, and a copy of the postgastric banding diet also is included. During the second visit, the candidate views a videotape presentation on the surgical risks and how the surgery will change eating habits and life-style. After the videotape, the surgeon explains the silicone gastric banding surgery, the long-term results, and the possible postoperative complications and surgical risks. The dietitian stresses the changes in eating habits. Before the patient enters the hospital, a gastrointestinal series and an ultrasound of the gallbladder are done. Contraindications include an active peptic ulcer, a large hiatus hernia, or a malignancy of the stomach. When gallstones are found, a cholecystectoniy may be done simuftaneously with the inflatable silicone gastric banding surgery. Intraoperative cholangiogram or 1317
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common bile duct exploration should not be done because of potential infection around the band.
Patient Preparation
A
t Irvington General Hospital, care of the morbidly obese patient is based on a teamwork approach among the medicalsurgical unit nurses, the OR nurses, dietitians, and specialists from the anesthesiology, pulmonary medicine, gastroenterology, and internal medicine/cardiology departments. Members of the consulting medical team should be well informed about the type of surgery and the potential complications. They also should be aware of changes in the patient’s eating patterns after the surgery so that the prescribed medications and diet will be tolerated. The medical-surgical unit needs rooms prepared for severely obese patients with special beds, toilet bowls, wheelchairs, gowns, and blood pressure cuffs designed for morbidly obese patients. After admission to the surgical floor, the patient undergoes routine preoperative tests including complete blood count, serum chemistries, a urinalysis, an electrocardiogram, and a chest xray. Baseline arterial blood gases are obtained on all patients because common complications from major surgery in obese patients are pulmonary congestion, atelectasis, and/or pneumonia. Pulmonary consultation is obtained for all patients. For patients with known cardiovascular problems, a cardiac consultation is requested. A pregnancy test is ordered for females unless they have had a hysterectomy. Height and weight are recorded. The physician is notified of any abnormalities. The patient is started on a full-liquid diet. A nurse also completes an assessment and history with emphasis on the patient’s dietary habits and psychosocial background. As the nurse establishes rapport with the patient, he or she assesses the patient’s knowledge and expectations of the surgery and gives the patient an opportunity to express feelings. Informing patients of what to expect in pre- and postoperative instruction will help alleviate some of the anxiety that accompanies any surgical procedure.
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The nurse instructs the patient in deep breathing and leg exercises as well as turning side to side every two hours postoperatively. An overhead trapeze is mounted to help the patient with postoperative turning. A respiratory technician shows the patient how to use the spirometer. The night before surgery, the patient’s abdomen is shaved and he or she receives a subcutaneous injection of heparin and a sleeping medication, if desired. The patient also receives an enema. Patients are NPO after midnight.
Preoperative Care
T
he morning of surgery, the nurse completes the preoperative checkliist and administers an antibiotic injection and another dose of heparin. Any preoperative medication is given as ordered by the anesthesiologist. The patient is transported to the OR holding area. The OR nurse greets the patient and verifies his or her identification. The anesthesiologist inserts the intravenous (IV) line and begins IV therapy with 5% dextrose in half-normal saline with 20 mEq potassium chloride. The circulating and scrub nurses set up the operating room according to the surgeon’s preference card. Instruments include a major basic set, gastric banding set, additional long instruments, vessel clips, and the modified Gomez retractor. The banding set consists of a kidney pedicle clamp, stomach clamp, hook, two Hegar dilators, four tonsil clamps, a long plain forcep, long Metzenbaum scissors, two mosquito clamps, and the banding instrument, which tightens the band around the stomach and holds it until the band is sutured. Additional long instruments include a knife handle, clamps, and scissors. Sutures used are in accordance with the preference card. A 3-mL syringe with an 18-gauge intravenous catheter is filled with steriile saline to irrigate and partially inflate the band. The gastric band is soaked in a neomycin solution. The scrub nurse sets up the sterile saline for inflating the band in a separate medicine cup. After the setup is finished, the circulating and scrub nurses make the first count of the instruments and sponges, needles, and sharps. The nurses 1319
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Fig 9. Inflatable silicone gastric band placed around the stomach.
complete three counts of sponges, needles, sharps, and instruments-one preoperatively, one when the peritoneum is closed, and one when the skin is closed. The circulating nurse then brings in the patient and helps move him or her to the OR bed. The OR bed is put in reverse Trendelenburg position which shifts the weight off the patient’s chest to help him or her breathe while awake. This position also provides the surgeon better visualization of the surgical site. The arm boards are attached to the table and positioned. Compression antiembolic stockings are placed on the patient’s legs and connected to the pump, which is then turned on. Blood pressure and heart rate are measured. Pulse oximetry is measured by placing a device on the patient’s fingertip that determines oxygen saturation with infrared light. The nurse explains to the patient what is being done to allay fear and decrease anxiety. 1320
After the patient has been anesthetized, the circulating nurse inserts the Foley catheter and applies the electrosurgical dispersive pad. The circulating nurse then scrubs the abdomen with povidone-iodine and pats it dry with sterile towels provided by the scrub nurse. After the surgeon and assistant are gowned and gloved, they finish prepping and draping.
Surgery
T
he surgery begins with the surgeon making an upper midline incision and dissecting subcutaneous fat from the right anterior rectus sheath. A small part of the sheath and a small part of the right rectus muscle are cut with the electrocautery knife to prepare a space for the self-sealing reservoir. The surgeon then opens the abdomen. A modified Gomez retractor is assembled to
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Fig 10. Banding instrument tightens and holds the band while the surgeon calibrates the stoma and stomach pouch. obtain good exposure of the surgical site. The surgeon opens the avascular portion of the hepatogastric ligament and, by blunt dissection with fingers, makes a tunnel under the stomach and through the suspensory ligament of the fundus proximal to the short gastric vessels. A Penrose drain is placed through the opening and wound around the stomach. A small opening is made next to the lesser curvature of the stomach, approximately 2 cm below the gastroesophageal junction and medial to the gastric vessels and vagus nerve. The surgeon irrigates the tube and balloon of the inflatable silicone gastric band to remove any air. The balloon is preinflated with 0.8 mL of saline solution. The surgeon then threads the band through the opening next to the lesser curvature and around the stomach (Fig 9) and removes the Penrose drain. 1322
After the anesthesiologist inserts the pouch and stoma calibrating tube through the mouth and into the stomach, the surgeon tightens the band with the banding instrument (Fig 10). When the pouch and stoma have been calibrated, the surgeon sutures the band together and excises the buckle and any extra part of the band. He or she places the tube connected to the inflatable balloon under the diaphragm and into the space prepared within the right rectus sheath. The self-sealing reservoir then is filled with the saline solution and connected to the silicone tube. All incisions are closed in the usual fashion. During surgery, the circulating nurse helps the anesthesiologist and keeps accurate records of any added sponges, needles, sharps, or other equipment. Because of the amount of fatty tissue on very obese patients, items could be misplaced. The scrub nurse tries to anticipate the needs
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of the surgeon and monitor instrument and sponge locations. Laparotomy rings are always used with laparotomy sponges. Using a magnetic mat helps keep the field neat and prevents the instruments from sliding. The scrub nurse must secure any specimens. The circulating nurse labels and records all specimens in the logbook. After the wound is closed, the area is cleaned and covered with narrow strips of nonadhesive dressing. The surgeon places transcutaneous electrical nerve stimulation electrodes on opposite sides of the suture line to alleviate postoperative pain. An abdominal binder is placed in some patients. The scrub nurse clears away the instruments, and the circulating nurse stays with the patient and anesthesiologist to prepare the patient for transfer to the postanesthesia care unit (PACU). The circulating nurse records urine output and IV intake. The electrosurgical dispersive pad site is checked and the skin condition recorded. Documentation is essential for the surgical procedure. Both the scrub and circulating nurses sign the nursing operative record and instrument sheets. The label of the band is attached to the chart for record keeping. Before transferring the patient to the PACU, the circulating nurse informs the PACU nurses. He or she gives them a verbal report that includes the name of the patient, the surgeon, the anesthesiologist, the type of procedure, drains, types of anesthesia, intake and output, allergies, medical problems, antibiotic or blood products given, and any problems encountered during the surgery. The patient is transported to the PACU by the hospital attendant, the circulating nurse, and the anesthesiologist. The head of the bed is raised before transporting. The patient receives oxygen through a nasal cannula during transport.
Postoperative Care
W
hen the patient arrives in the PACU, the nurses assess and record his or her airway patency and vital signs. The patient is given oxygen by mask as ordered.
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The patient is encouraged to take deep breaths, move feet, and bend knees. F’atients are helped with turning if they request a position change. The head of the bed is kept elevated to make the patient more comfortable and enhance breathing. Nurses administer pain medications, record intake and output, and check the wound dressing. Compression antiemblolic stockings stay in place. Arterial blood gases ;ire checked on all patients who weigh more than 300 pounds or who have histories of asthma or chronic obstructive pulmonary disease. Nurses give the patient emotional support and reassurance throughout his or her stay in the PACU. A scoring system is used as a guide for discharging the patient from the PACU, normally in two to three hours. When tlhe patient is ready for transfer to the surgical unit, the nurses are notified and informed of any special needs, such as oxygen. Most patients go directly to the medicalsurgical unit from the PACU. The surgeon and anesthesiologist decide if the patient requires intensive care. After the patient is returned to the medicalsurgical unit, the nurse assess him or her for respiratory distress, vital signs, body temperature, signs of pain, bleeding, circulatory impairment, and body alignment. No nasogastric tube is inserted in a patient with a gastric band. The patient is allowed to take sips of water. The patient is instructed to take 10 to 15 deep breaths per hour and to exercise his or her legs and arms. Extra pillows are used to splint the abdomen when deep breaths are taken. Patients receive oxygen through a nasal cannula for 24 to 48 hours postoperatively. Antibiotics and heparin administration is continued. Pain medication is given, as neelded, to alleviate postoperative pain and provide comfort. On the second postoperative day, antibiotics and IV therapy are discontinued and the Foley catheter is removed. The postgastric banding diet is started and progressed daily. The patient is instructed to eat slowly, chew wdl, and stop eating when full. Small straws are used to sip beverages to reduce swallowed air. Independent inspiratory spirometry is continued. The patient walks with assistance. 1323
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By the seventh or eighth postoperative day, the patient is discharged. Before discharge, the surgeon removes the sutures and gives discharge instructions describing activities,diet, and follow-up visits. The nurse and dietitian reinforce the instructions. The dietitian gives the patient copies of a diet to follow. The patient then is weighed to determine weight loss during the hospital stay. The importance of office follow-up visits is stressed. Local patients are encouraged to visit monthly. Patients are not charged for postoperative visits. Out-of-state patients correspond through questionnaires mailed to the physician every three months. After discharge, the patients must begin changing life-style and eating habits because the success of the surgery depends on them. 0 Notes 1. B M Hannon, T G Lohman, “The energy cost of overweight in the United States,” American Journal of Public Health 68 (August 1978) 765-767. 2. Health Implications of Obesity (Bethesda, MD: National Institutes of Health Concensus Development Conference Statements, February, 1985). 3. P Berchtold et al, “Cardiovascular risk factors in gross obesity,” Infernational Journal of Obesiw 1 (March 1977) 219. 4. Health Implications of Obesity. 5. Ibid. 6. Ibid. 7. A N Kremen, J H Linner, C H Nelson, “Experimental evaluation of the nutritional importance of proximal and distal intestine,” Annals of Surgery (September 1954) 439-444; J H Payne, L T DeWind, R R Commons, “Metabolic observations in patients with jejunocolic shunts,” American Journal of Surgeiy 106 (July 1963) 273-289. 8. H W Scott, Jr et al, “Jejunoileal shunt in surgical treatment of morbid obesity,” Annals of Surgery 171 (May 1970) 770-782. 9. N Scopinaro et al, “Two years of clinical experience with biliopancreatic bypass for obesity,” American Journal of Clinical Nutrition 33 (February 1980) 506-514. 10. E E Mason, C Ito, “Gastric bypass in obesity,” Surgery Clinics ofNorth America 47 (December 1967) 1345-135 1. 11. E E Mason et al, “Gastric bypass for obesity after ten years experience,” International Journal of Obesity 2 no 2 (1978) 197-206. 12. Zbid; Mason, Ito, “Gastric bypass in obesity,” 1345-1351. 13. J F Alden, “Gastric and jejunoileal bypass: A comparison in the treatment of morbid obesity,” 1324
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Archives ofsurgery 112 (July 1977) 799-806. 14. W 0 Griffen, Jr, V L Young, C C Stevenson, “A prospective comparison of gastric and jejunoileal bypass procedures for morbid obesity,” Annals of Surgery 186 (October 1977) 500-509; E E Mason et al, “Gastric bypass in morbid obesity,” American Journal of Clinical Nutrition 33 (February 1980) 395405. 15. C A Gomez, “Gastroplasty in morbid obesity,” Surgery Clinics of North America 59 (December 1979) 1113-1120. 16. J B Freeman, H Burchett, “Failure rate with gastric partitioning for morbid obesity,” American Journal of Surgery 145 (January 1983) 113-119. 17. H L Laws, “Standardized gastroplasty orifice,” American Journal of Surgery 141 (March 1981) 393394. 18. G V Eckhout, J F Prinzing, “Surgery for morbid obesity: Comparison of gastric bypass with vertically stapled gastroplasty,” Colorado Medicine 78 (April 1981) 117-122; J P OLeary, “Partition of the lesser curvature of the stomach in morbid obesity,” Surgery, Gynecology & Obstetrics 154 (January 1982) 85-86; G V Eckhout, “Long-term results of vertical gastroplasty with chromic or Silastic ring supported gastric stomach vs gastric bypass for treatment of morbid obesity,” presented at the First Annual Meeting of the American Society of Bariatric Surgery, Iowa City, Iowa, June 1984. 19. E E Mason, “Vertical banded gastroplasty for obesity,” Archives of Surgery 117 (May 1982) 701706. 20. K Kolle, “Gastric banding,” presentation at the OMGI Seventh Congress, Stockholm. Abstract 145:37; 0 Bo, 0 Modalsli, “Gastric banding, a surgical method of treating morbid obesity: Preliminary report,” International Journal of Obesiw 7 no 5 (1983) 493499, M Molina, H Oria, “Gastric banding,” presentation at the Sixth Annual Bariatric Surgery Colloquium, Iowa City, Iowa, June 1983. 21. J B Holt, C L Castiglione, P E Trowbridge, ‘‘Immediate and long-term results of vertical banded gastroplasty for morbid obesity,” Connecticut Medicine 51 (October 1987) 638-642; H J Sugerman et al, “Weight loss with vertical banded gastroplasty and Roux-Y gastric bypass for morbid obesity with selective versus random assignment,” American Journal of Surgery 157 (January 1989) 93-102. 22. Guidelinesfor Selection of Patients for Surgical Treatment of Obesiw (San Francisco: The American Society for Bariatric Surgery, 1986).