Bioengineering - Gastric Balloon Development - Coursework Example

Name : Tutor : Title : Gastric balloon development Institution : Date : @ 2016 BIОЕNGINЕЕRING Gastric balloon development Introduction The gastric balloon, also known as the intra gastric balloon is soft, elastic and a silicone balloon available for the purpose of weight loss. The device is placed inside the stomach of the obese person through a camera that penetrates into the stomach via the mouth. Once the balloon is positioned in the stomach, it is filled with sterilized saline whose main function is to occupy the balloon and cause a feeling of fullness within the stomach. The obese person is thus able to reduce the quantities of food they take and hence help in reducing the body size (William 2008 pp. 27). The process is very simple and less disturbing as the placement of the balloon takes around 20 minutes and should be done by qualified gastroenterologists. The process does not involve any surgery. The balloons should be tested for quality and should be designed by highly qualified bio-engineers. The balloon is reversible and helps in reducing hunger temporarily, controlling the intake of food, initiating some changes in behavior and help in achieving an overall weight loss of 10 to 30kgs. The balloon is uninflated, ingestible and substantially liquid-impermeable with both an exterior and interior surface bounding the lumen. The balloon also encloses an emissive substance that liberates gas to inflate it upon contact with reactants (Sreenivasa 2015 pp.86). There is also a vessel within that comprises a receptacle fabricated of the gelatin and having a mouth. The receptacle is attached at the mouth to a septum (self-sealing valve) by a liquid-impermeable seal. This paper discusses the structure, the development and the design process of the most current and updated gastric balloon. I this paper, the use and application of the balloon is discussed as well as how the balloon design and features can be improved for future use. The origin of gastric balloons can be traced back in 1982 and was proposed as a way of controlling obesity by Nieben bringing in the use of the first artificial space occupying intragastric balloon for losing weight. It is often considered as a non-surgical restrictive procedure for losing weight as it theoretically affects both gastric capacity and stretch receptors thereby increasing satiety while decreasing the available residual volume for food (William 2008 pp. 38). The intragastric balloon is a saline-filled balloon that can hold a maximum volume of 700mL. It is technically inserted into the patient’s stomach in a similar way as other balloons such as BIB and Silimed. However, it is a bit more peculiar as the manufacturer is recommended to treat the outer surface of the balloon with a lubricant before it is implanted and also introduce the lubricant under the sheath so as to provide easy detachment of the balloon from the filling tube. After it is implanted, patients take antiemetics like metoclopramide and thiethylperazine for a few days at home. It is an effective method of slashing off weight temporarily with low mortality and morbidity. Its design comes from the design of the commonly approved Bioenterics Intragastric Balloon (BIB) (Sreenivasa 2015 pp.106). The operation of the intragastric balloon is best understood by considering the functional components of the device. The size of the balloon is determined by the pressure of the fluid that has been used to fill it. Before insertion through the esophagus, the balloon must be in an uninflated condition. This will allow ease of passage and also minimizes the size of the balloon’s lumen. During insertion as well as during the manufacturing of the device, it is sealed at ambient or reduced pressure relative to the pressure outside it. Other patients swallow the balloon and transported to the stomach via peristalsis. Upon positioning in the stomach, the balloon self-inflates in the stomach of the patient without the need of any external source like pump or syringe for delivering fluid (William 2008 pp. 87). There is a recent invention that achieves self-inflation by the reaction between acid and an emissive substance that is in the balloon’s lumen that results in generation of gas that inflates it. This inflation is possible from the fact that the balloon is substantially fluid-impermeable and the greater volume of the gas molecules of gas about the same molecule number of solid under same pressure and temperature. The acid solutions useful in the device include citric acid, acetic acid as well as hydrochloric acid solutions. The solvent commonly used to make the solutions is water, but substitution is allowed if the acid dissolves sufficiently in another solvent like ethanol provided that the substitute does not have diverse side effects to the subject. Emissive substance liberates gas upon contact with the solutions of the acid (William 2008 pp. 96). The preferred emissive substances include alkaline metal carbonates and bicarbonates and solutions (preferably aqueous) such as sodium bicarbonate (NaHCO3) combined with potassium bicarbonate (KHCO3) which is mainly used as they liberate carbon dioxide upon reaction with acid. The acid and the emissive substance are separated from each other until the device is implanted into the stomach of the patient so as to prevent premature inflation of the balloon. This is achieved by using solid acid and emissive substance. In such a state the two are unable to react and liberate gas. They can also be separated by positioning one in the vessel while the other on the lumen of the balloon (Familiari, Boskoski, Marchese, et al., 2011 pp. 69). This self-inflating intragastric device may be availed to sufficiently trained personnel or as part of a kit. The kit may also contain other things like the vial, ampule or pre-filled syringe containing an activating liquid. The nature of this activating liquid will depend on whether the acid in the balloon is a solid acid. The solutes of the liquid should not interfere with the inflation of the balloon (Sreenivasa 2015 pp.102). The kit should also contain instructions on how to activate, administer, use and stop using the device. The device is activated after an approximated delay time before administration when the acid and the emissive substance are caused to react. The activating fluid causes a breach of the vessel wall which allows the emissive substance to be in contact with the acid. The reaction of the two commences and reaction starts that generates a gas that inflates the balloon. This should occur only when the balloon is in the stomach of the subject. There should be an exact timing when the activating liquid is communicated such that it does not happen early as the inflation may obstruct the esophagus or if it happens late the balloon may pass to the intestines and cause an intestinal obstruction (Familiari, Boskoski, Marchese, et al., 2011 pp. 93). A self-sealing valve, preferably a septum, is used to administer the activating liquid into the balloon. The activating fluid is administered directly by insertion of the tip of the needle of the syringe that contains the activating liquid via the septum and then advancing the plunger, which may be pulled back and advanced again severally to allow air to escape the vessel (Benjamin et al., 1988 pp500). Alternatively, during fabrication, the vessel can be evacuated a process that may be accomplished coincidentally to the evacuation of the balloon. For the patients who swallow the device, swallowing is facilitated by having a container in place that is made of material that dissolves in gastric fluid more rapidly than the vessel. The uninflated balloon is then compacted and inserted into the container with lots of caution such that the self-sealing valve is allowed on the surface of the compacted balloon. The container may be transparent, semitransparent or is marked in order to ease the identification of the self-sealing valve after the balloon forced to be compacted (Sreenivasa 2015 pp.181). The device can be activated once the location of the self-sealing valve is visible by simply piercing the container with the needle that is used to inject the acid. This procedure has no effect on the delay as it is controlled by the degradation rate of the inner vessel. Water gulps and hard gelatin capsules may also be used to ease the swallowing of the device. The surgical procedure commences with the numbing of the throat of the patient with a spray in a treatment room set up. This numbing may feel strange, but it is vital as it helps the patient tolerate the instruments that are used in the procedure. Other options may be discussed with the patient beforehand such as injection that makes the patient sleepy such that he/she is sleepy. The nurse responsible for the procedure will then wait until the patient is comfortable and then insert a plastic mouth guard between the teeth of the patient to keep his/her mouth open for the scope. The scope is then passed through the mouth of the patient and into his/her stomach, a procedure that is not painful as the patient can breathe without worry. In order to have a clear view, the doctor may have to pass some air down the scope, a process that may feel strange too as it may make the patient have the urge of belching. The scope is then removed followed by the balloon being passed into the stomach of the patient and then inflated with air or saline solution. Then a second insertion of the scope into the stomach will follow to confirm or double check whether the balloon is in the right position and whether it is inflated properly (Sreenivasa 2015 pp.206). The FDA’s center for Devices and Radiological Health (CDRH) is the body responsible for the regulation of the firms who manufacture, repackage relabel and /or import medical devices sold in United States. Medical devices are classified into class I, II and II. WHO reinforces its role in providing support to its member states in an attempt to offer improved medical device regulatory systems to protect patients from the potential risks of unsafe technology. The classification schemes for medical devices in other regions like European Union and Canada are predominantly rule-based. The “Essential principles of safety and performance of medical devices” recommended by the GHTF (SG1-N020R5) clearly stipulates that medical devices should be designed and manufactured in such a manner that it will serve its intended use by the virtue of the experience, technical knowledge and the training of the users and not compromise the health safety of the subject. The International Organization for Standardization (ISO) has produced a document (ISO 14971:2000) that provides a framework for risk analysis, risk evaluation and risk control for the manufacturers during design and development of clinical devices as well as a way of monitoring the safety and performance of the same device after sale. The gastric balloon should then be designed in a manner that it adheres to these regulation and standards (Eckhauser et al., 1984 pp44). Before the surgeon and the team responsible for the surgery embark on the procedure, the patient is involved in a health a pre-procedure health assessment. Here the patient is asked questions about his/her medical history and medications as well as surgical history since some complications may crop up if the patient has ever had prior procedures on the stomach (Eid et al., 2011 pp. 16). The surgeon may enquire for certain tests like x-ray, ECG as well as blood tests. The patient is strictly advised to adhere to the instructions of the surgeon while preparing for the day of the procedure. The surgeon among other things will ask the patient to fast for 12 hours. Before the procedure, the patient will be asked to wear compression stockings (anti-embolic) as they help blood flow in the deep veins in the legs and also in reducing the risk of developing blood clots. The patient should extend this for six weeks after the procedure (Familiari, Boskoski, Marchese, et al., 2011 pp. 103). To be precise, the balloon procedure is much less complicated than the more aggressive weight loss surgery options. The gastric sleeve surgery for instance, which is the least complicated of the more aggressive options will take about 2 hours of surgery time and about 2 to 3 days in the hospital to recover. However, this gastric balloon procedure does not take more than half an hour, and most of the patients leave the hospital the very same day they had the procedure done (Eid et al., 2011 pp. 33). The recovery period as mentioned above for a typical balloon patient is mainly one day as the patients return home on the same day. It is highly recommended that the patient is accompanied by an individual who is willing and able to drive the patient home and take care of him for at least a whole day after the procedure. The throat of the patient will probably be sore following the procedure as the balloon was inserted via the mouth. The risks and issues of intragastric balloon are relatively low. However, there are potential risks and side effects just like in any other medical procedure. Much of the se are discussed by the doctor with the patient (Eid et al., 2011 pp. 56). The balloon is not recommended for patients with prior gastrointestinal surgery with sequelae (an abnormal condition related to the surgery), potential upper GI bleeding, inflammatory diseases of the GI tract, prior open or laparoscopic bariatric surgery as well as any medical condition that would not permit endoscopy. The balloon is also not recommended for the patients who are alcoholic or addicted to drugs, the ones who receive daily prescribed treatment with, anti-inflammatory agents, aspirin, anticoagulants or other gastric irritants, the ones not willing to participate in a diet that is medically-supervised as well as behavior modification program and the ones who are currently or may be pregnant or breast-feeding (William 2008 pp. 127). There is a possibility that complication will arise just as like any other surgery. The most common complications associated with the balloon include: the risks associated with the endoscopic procedure and sedation which involves being put into sleep. The esophagus too may be punctured during the procedure as the surgeon uses a scope while performing the procedure. There is a chance that the esophagus could be punctured by the scope, a case that is rare. There is also a possibility that the balloon may deflate in the stomach and cause blockage. However, this can be solved by one system, the ReShape Integrated Dual Balloon System that has two independent balloons such that if one deflates the other will keep the entire apparatus in the stomach. Most of the balloons are also filled with a dye that turns the urine of the patient into an unusual color so that he/she knows when to alert the surgeon in case there is an issue with the balloon. The surgeon will most likely prescribe anti-ulcer medication to reduce the risk of an ulcer in the stomach for the whole period that the balloon is in the stomach of the patient. Cases of stomach rapture are extremely rare and will mainly appear if the patient has had a prior stomach procedure (Familiari, Boskoski, Marchese, et al., 2011 pp. 172). Many surgeons will not be willing to perform the procedure if the patient has had a prior stomach procedure. In an event that the surgeon discovers a very large hiatus hernia, he/she will be forced to end the procedure prematurely for safety reasons in the middle of the procedure. Others include bleeding or perforation that may result from injuries during the process of insertion or removal. This may deem it necessary to have a surgical correction. The oxygen levels may be low in the blood and some patients experience an irregular heartbeat, which may result to a heart attack. This requires constant monitoring of the oxygen level and the pulse throughout the procedure. For the patients who are reluctant to tell the doctor that they have crowned teeth or bridgework, they expose themselves to a slight risk (William 2008 pp. 154). The chance of the occurrence of these risks is small, but it is imperative that the subject is aware of all of them and that he/she has all the information before the procedure commences. In the first couple weeks after the procedure is performed, the patient will experience nausea, cramps and possibly vomiting as the stomach is readjusting to the balloon presence. Others will experience bloat and are encouraged to keep in touch with the surgeon and not to feel discouraged as such a feeling is a clear indication that the balloon is doing its job. The patient is advised to adjust to his/her eating as well as drinking habits no matter how difficulty it may feel. The patient is advised to be on a liquids and soft-food-only diet for a couple weeks after the procedure, after which the patient will be forced to permanently adjust to a specific diet in order to reinforce and maintain the loss of weight (Familiari, Boskoski, Marchese, et al., 2011 pp. 201). During the first day, the patient is on clear liquids only such as water, ice chips, broth, crystal light, powerade with zero calorie only and propel fitness water with zero calorie only too. On top of this matter, there are other vital factors to consider too such as: the patient is advised to drink warm liquids over cold liquids, avoid carbonated drinks as they will cause gas and bloating. The patient is also advised to take at least 8 cups of liquid per day so as to keep hydrated and avoid constipation. Precautions also ensue as one should start by taking small sips and wait for a minute or two between sips and then increase the amount as he/she gets more comfortable. The patient should sit upright after drinking to allow gravity to help the system and if he/she is resting, he/she should use a recliner rather than lying flat. The patient should not drink more than one cup of coffee or caffeine drink per day as caffeine can cause dehydration and lead to cramping and diarrhea (Eckhauser et al., 1984 pp49). The victim must still maintain a liquid diet for 2 through 7 after surgery, but he/she can begin to include non-clear liquids and try to take about 2 liters a day with no more than 3 - 3.5 ounces (100 ml) in one sitting. The following are some of the recommended liquids to help in getting all nutrients: semi-skimmed milk to be taken at least 600 ml a day, herbal teas, low calorie/reduced sugar squash, clear beef or chicken broth soup, water or juice mixes as well as any protein drinks recommended by the surgeon (Benjamin et al., 1988 pp516). One should then switch to a pureed food diet about a week after surgery. The patient should work with the doctor to know the exact timing and the type of foods that he/she should eat. The food will likely consist of lean protein foods such as eggs, fish, poultry, cheese, or healthier dairy and soy products all of which should be accompanied by high ratios of fruits and vegetables. The victim can resume to the normal diet after the body has gotten used to the balloon with a few restrictions. The patient is advised to adhere to the dietitian or nutritionist’s instructions to the letter, with any vitamin or mineral regimen inclusive. The patient should sip water after every meal to reduce the risk of vomiting as the balloon is washed off and in any case that the patient vomits, he/she should give the stomach some time to rest. Pasta should also be avoided as it tends to stick to the balloon increasing the chances of vomiting (Benjamin et al., 1988 pp520). There is a risk of the balloon interfering with the stomach of the patient and hence I can say that the gastric balloon is not designed as a long term fix. It is either removed or replaced sometimes after a period of say 12 weeks to 1 year depending on the type of the patient has got. When the balloon is ready to be removed after six months of insertion, the hospital makes arrangements with the patient for removal and send an appointment later. The surgeon is the one who is responsible for coordinating the insertion of the balloon as well as the removal of the same. After the balloon is removed from the patient, he/she is then advised to stick to the managed weight loss program and then maintain the newly established diet for the rest of the life. Some patients combine the balloon with a lifestyle management program for 6 months after its removal to ensure that they maintain the weight lost when the balloon was in place (Eckhauser et al., 1984 pp52). The cases of the effects of the gastric balloon on regulation of hormones in obese bodies are minimal as the latter is a system that is complex and is regulated by other factors. The hormones that critically influence the regulation of food intake and body weight are leptin and ghrelin. Ghrelin, which is a 28-amino acid peptide secreted mainly by the stomach stimulates both energy gain and the secretion of growth hormone (GH) as well as insulin that leads to a gain of weight. The levels of ghrelin may be influenced by age, BMI, gender, glucose, growth hormone and insulin. On the other hand, leptin is a 167-amino acid protein that is produced by adipocytes, in the hypothalamus. It acts as an anorexigenic molecule, proportionally released to the amount of fat stored in the white adipose tissue. It also suppresses food intake in the hypothalamus as well as increasing energy expenditure. The levels of ghrelin increase significantly three months after the balloon is inserted into the patient’s stomach. But after this, the levels subsequently decreased. The adipose tissue and the plasma leptin levels also declined (William 2008 pp. 223). Researchers have invented a gastric balloon that deflates upon completion of a predetermined, prolonged period. This will imply that the convenience of the patient and the medical personnel will depend on whether the balloon has deflated itself automatically or whether it has to be manually withdrawn from the stomach of the subject. The balloon under the new invention will remain in the stomach of the topic for the entire period of inflation and deflation. It remains inflated for from 20 days to 60 days preferably. After the device has deflated itself, it can then pass through the rest of the digestive system without any injury. This minimizes the risks and complications that could have aroused from the medical procedure of removing the same (William 2008 pp. 264). This self-deflation technique is achieved in the present invention by the use of slowly biodegradable, acid degradable or degradable pepsin materials in its design. The preferred biodegradable materials that can be used for this purpose include polyglycolide (Dexon), poly(1-lactide), poly(lactide-co-glycolide), poly(d, 1-lactide), poly(dioxanone), poly(ξ-caprolactone), poly(glycolide-co-trimethylene carbonate), polyglyconate (Maxon) polyanhydrides poly(hydroxybutyrate-co-hydroxy valerate), or poly orthoesters. Polydioxanone, Monocryl® (poliglecaprone) and Vicryl are yet more preferred biodegradable materials. Polymeric material combinations may also be used if they contribute to better functioning of the device. A more resorbable polymer, for instance, can be blended with a more rigid and less rapidly degrading polymer to yield better quality rapid initial degradation of the device while maintaining a rigid framework for an extended period. The bladder of the degradable material can alternatively be fabricated by say making the balloon with Vicryl (Ethicon) or PDS. These self-deflating devices should then be packaged and stored under dry conditions. This will help prevent the possible premature degradation before they are implanted in subjects’ stomach (Sreenivasa 2015 pp.213). Conclusion The intragastric balloon system is a safe and effective procedure that has very minimal complications while treating morbidly obese patients. Individuals perceive the method as a restrictive surgery majorly by the patients awaiting bariatric surgical treatment. However, in the real sense, this method is purely unrestrictive. It is a positively affects the glucose homeostasis as well as the molecules that regulate lipid and energy metabolism. Complications and risks associated with the procedure are rare and minimal. For improved performance and reduction of the very rare cases I have discussed above, a gastric balloon that deflates upon completion of a predetermined, prolonged period has been invented. This will imply that the convenience of the patient and the medical personnel will depend on whether the balloon has deflated itself automatically or whether it has to be manually withdrawn from the stomach of the subject. Bibliography Marina .K, Bruce M., & Sayeed. I,(2015). Metabolic Syndrome and Diabetes: Medical and Surgical Management: Springer, - Medical - 270 pages Sreenivasa S., (2015). Gastrointestinal Endoscopy: New Technologies and Changing Paradigms: Springer - Medical - 222 pages William G. (2008).Biotechnology and Bioengineering: Nova Publishers - Science - 272 pages Benjamin et al., (1988). 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