Obesity as an Epidemic Proportions Around the World - Literature review Example

?OBESITY Introduction Obesity around the world is reaching epidemic proportions. The health risks of obesity touch on all parts of a patient's life and all parts of their medical treatment. Surgical teams have been and will continue to see more overweight, obese, and morbidly obese patients on their operating tables, and must know how to treat the specific needs of such patients. The aim of this review is to focus on the issues that impact on the safety of obese patients during the perioperative phase. There are four major themes that will be considered: 1. Obesity Measurement and Definition, 2. Co-morbidities, 3. Surgery, and 4. Anaesthesia. The following databases were searched for literature for this review: Pubmed, Cochrane library, Wiley, Cinhal Randomized Controlled Trial (RCT), Ovid, NHS Evidence, World Health Organisation Website and Medline. Keywords searched were obesity, obese, risks, co-morbidities, surgery, bariatric, anaesthesia, perioperative, prevention and airway. Obesity Measurement and Definition Obesity can be measured using total body weight, body mass index, body fat composition, fat mass index, and fat free mass index, and is specifically defined as having a body mass index greater than 30 kg/m2(Zhang & Wang, n.p.; Hjartaker, Langseth & Weiderpass, p 72). Risk for co-morbidities seems to be better indicated by measures of fat distribution, such as height-weight comparison or waist circumference, than by total weight (Zhang & Wang, n.p.; Hadaegh et al., p 310). Body mass index is not as accurate at determining true levels of overweight and obese nor at estimating risk factors, but it is a faster method at screening a larger population (Zhang et al., p 244). Overweight and obese adolescents tend to have poorer overall health than their normal weight peers, but they do not report more health issues requiring medical care. Those that do have other health issues tend to be overweight or obese currently, rather than having a history of weight problems. Weight loss can therefore help reduce many of the of the health risks associated with childhood obesity (Wake et al., p 162). However, those adolescents who have co-morbid type II diabetes and obesity are also more likely to have higher arterial stiffness than their peers (Urbina et al., p 1692). This is a concern due to the fact that paediatric type II diabetes is quickly becoming a public health crisis (Dea, p 42). Also, obese children with asthma have a much higher rate of nighttime desaturation, or lack of oxygen. They were also more prone to snoring and other respiratory issues that could lead to hypoxia (Ross et al., p 877). The presence of overweight and obesity in young children seems to be primarily a result of their home environment, and is especially related to the parental attitude toward food and exercise (Weker, p 3). We can extrapolate that a patient's attitude toward food and health in childhood will have a profound effect on their weight as an adult. Many children with congenital or acquired heart disease become overweight or obese as a result of restrictions imposed on their activity level. Healthy levels of exercise and healthy life style choices are often forgotten in patient education, as the focus is often solely on preventing the worsening of the existing heart condition and fail to protect the young patient's overall health (Pinto et al., p 1157). The best method for preventing obesity is to change the eating habits of children before they become overweight or obese. This can be done by increasing the attractiveness of healthy lifestyle choices and healthy foods, especially in schools, where most children spend the majority of their time away from home. Schools should offer and encourage sports and other after-school activities, and offer remedial physical education courses for any student in poor physical shape (Della Torre, Akre, & Suris, p 233). Co-morbidities Eighteen major co-morbidities have been identified that show statistically significant connections with obesity or overweight. The conditions and diseases that are most strongly correlated with overweight or obesity in adults are: “incidence of type II diabetes, all cancers except esophageal (female), pancreatic and prostate cancer, all cardiovascular diseases (except congestive heart failure), asthma, gallbladder disease, osteoarthritis and chronic back pain” (Guh et al., p 1). The most common co-morbid condition in overweight adults is Type II diabetes. This is the most strongly correlated co-morbidity for obese or overweight adult women (Guh et al., p 1). Mobility issues in obese adults are a vicious cycle, causing decreased levels of activity that can lead to increased body weight and even further reduced mobility. Increased levels of overweight and obesity are correlated almost perfectly linearly with decreased lower limb mobility. Obesity alone is a risk factor for decreased mobility in older adults, without any other metabolic syndrome or conditions needing to be present(Stenholm et al., p 84). Body mass index and waist circumference are shown to be good indicators of risk for impairment in walking, stair climbing, and chair rise activities. Losing the excess weight has been found to be the most effective method for returning mobility in all functions. (Vincent, Vincent, & Lamb, p 568). Chronic pain in elderly adults is also closely connected to mobility impairment and obesity (McCarthy et al., p 115). Obesity has been strongly tied to an increased risk of oesophageal adenocarcinoma and colorectal carcinoma, as well as gastric cardia adenocarcinoma, breast cancer, endometrial cancer and kidney cancer (Donohue et al., p 628; Hjartaker, Langseth & Weiderpass, p 72). Obesity can also cause chronic acid reflux, which has been linked to esophageal adenocarcinoma (Lofdahl, p 128). While a high body mass index and a high total body weight are strong indicators of possible cardiovascular disease, high blood pressure risk is most strongly tied to fat mass index, not total body weight. (Zhang & Wang, n.p.).Obesity is a risk factor for atherosclerosis by itself, and associated with many other risk factors. However, the exact relationship between cardiovascular disease and obesity is still not clear, due to the extremely large number of variables present in any analysis of this type. Even still, studies show that the best public health method to reduce the rate of atherosclerosis in older adults is to reduce the incidence of overweight and obesity in the general population (Grundy, p 2595). Compounding the mystery surrounding obesity is the finding that obese patients have a higher rate of survival after myocardial infarction or congestive heart failure than normal weight heart attack sufferers (Curtis et al., p 55). In addition to this finding is the fact that compared to normal-weight men with hypertension, obese men with hypertension have longer life spans (Amundson, Djurkovic, & Matwiyoff, p 583) Chronic pain brought on by obesity raises the chances of developing depression or anxiety in the elderly (McCarthy et al., p 115). Up to 35% of obese patients seeking treatment suffer from anxiety disorders and 30% suffer from mood disorders. Additionally, 28% of obese patients in one study were found to have a personality disorder and 18% to have an eating disorder (Carpiniello , p 119). It is extremely difficult to determine, however, if the disorders caused the patients to overeat and become obese, or if the psychiatric disorders were a result of low self-esteem, poor self image, and societal rejection due to the patients' obesity. Studies have linked obesity in women to difficulty conceiving. The major reason behind this is that obese women are more likely to suffer from a highly irregular menstrual cycle and have a disturbed hormone balance. The hormone balance is affected by the higher levels of leptin found in obese women, which has been found to lower fecundity. Also, women with poly-cystic ovary system who are also obese experience worse symptoms, including lower fertility, than others with the condition (Brewer & Balen, p 347). After becoming pregnant, obese women have a much higher rate of caesarean delivery and pre-eclampsia than other patients (Soens et al., p 6). The use of global anaesthesia to treat these conditions greatly increases the chances of health complications in the mother and the newborn (Vallejo, p 175). Early neonatal fatalities are much more common with maternal morbid obesity, and the risk rises with every increase in the mother's body mass index (Salihu et al., p 1410). Surgery Surgery in obese and overweight patients is much more risky than in normal weight patients. Despite this, the most cost-effective and efficient method of weight loss in morbidly obese adults, once a traditional diet has failed, is bariatric surgery. This is especially true when preventing weight gain in the long-term (Picot, p 215). Roux-en-Y bypass results in more weight loss and fewer surgical revisions than adjustable gastric banding surgery, which makes it a more efficient method for the money. Roux-en-Y patients were found to have lost nearly 75% of their excess body weight within five years of surgery (Christou & Efthimiou, p E249). Bypass surgery is also more effective than vertical banded gastroplasty, and approximately equal to isolated sleeve gastrectomy and banded gastric bypass methods, which are also better than the adjustable banding methods (Colquitt et al., p 2). Obesity greatly increases the chances of failed intubation or a difficult intubation (Soens, p 6). Especially in obese children, the risk of critical respiratory adverse events is much higher in obese and overweight patients. This is further increased if the patient has co-morbidities (Tait et al., p 375). Early intubation can help prevent adverse respiratory events in obese surgery patients, as can the use of laryngeal mask airway (Zoremba et al., “Comparison between intubation”, p 436; Vallejo, p 175). In fact, intubating laryngeal mask airway has been found to be equally successful in both lean weight and obese patients, with a 94% success rate for intubation in obese patients. One particular study found that use of intubating laryngeal mask airway was easier for surgical staff to use in obese patients than in lean patients (Combes et al., p 1106). Sleep apnoea is primarily a disease of the obese. The condition is caused when a partial or complete block of the airway occurs during sleep, with at least five episodes occurring per hour of sleep. Unfortunately for those individuals suffering from sleep apnoea, there is no drug treatment. The most effective treatment involves body fat loss and total body weight reduction (de Sousa et al., p 340). Obese adults are also at much higher risk for sleep hypo-ventilationn, which can be co-morbid with hypoxia and is the primary risk factor for acute hypercapnic respiratory failure (BaHammam, p 543). All of these factors increase the chance of an adverse respiratory event during surgery, bariatric or otherwise. Most bariatric surgeries can be carried out with either a traditional open method or a keyhole/laparoscopic method. The laparoscopic method results in a shorter healing time and fewer immediate complications; however, more surgical revisions may be needed with laparoscopic methods (Colquitt et al., p 2). Additionally, “safe bariatric short-stay surgery is feasible with a dedicated anaesthesiological concept in an expert surgical team” (Bergland, Gislason, & Raeder, p 1394). Anaesthesia Studies have found that anaesthesia in obese patients is better dosed by using a lean body weight measurement than using a total body weight measurement (Ingrande, Brodsky, Lemmens, n.p.). In fact, there is a linear relationship between lean body mass and clearance in morbidly obese surgery patients, unlike with total body weight. The delay in awakening from anaesthesia shows how unsafe the total body weight dosage method can be for those patients (McLeay et al., p 1626). Obese patients, especially children, have been found to have a much higher incidence of perioperative respiratory events than those of normal body weight (Veyckemans, 2008). This is partially due to the loss of muscle tonicity of the diaphragm under anaesthetic being amplified in the obese. Being obese can lead to a loss of postoperative lung capacity that is as high as fifty percent of the preoperative capacity (Zoremba, p 436). Therefore, such patients must be carefully monitored for oxygen saturation while recovering from anaesthesia and surgery. The use of an epidural in pregnant obese women can help mitigate the dangers of total anaesthesia during delivery (Soens et al., 2007). However, morbidly obese women have a much higher rate of failed epidural attempts and complications due to epidural anaesthesia than normal weight women. Early epidural placement can help reduce these dangers, but they are still extremely high (Vallejo, p 175). Overweight patients respond disproportionately strongly to propofol, with more highly reduced oxygen saturation and lung function for up to a full day after surgery is completed. This risk can be mitigated through the use of desflurane as an anaesthetic instead of propofol. Even as body weight increased, the loss of respiratory function with desflurane anaesthetic does not (Zoremba et al., “A Comparison of Desflurane”, n.p.). These findings suggest that the use of desflurane is more highly indicated in obese patients even when other safety factors are considered. Conclusion In order to better serve the high-risk obese patient, obesity measurement standards need to be updated. Use of body mass index as the sole tool for measuring obesity allows a significant portion of the population to be wrongly categorised as a lower risk than they actually are. Therefore, surgical centres could better control the surgical risks of these clients by using more exact tools such as waist circumference and body fat percentage. Increasing their risks during surgery, obese and overweight patients are prone to innumerable co-morbid conditions. Mobility limitations, for example, can slow the healing process by impeding rehabilitation activities. Chronic pain brought on by obesity could affect recovery care, as it could be difficult for the nursing staff to determine what pain is brought on by surgical complications and what is usual for that patient. Surgery is also more risky simply due to the layers of fat between the skin and internal organs. Intubation, for example, becomes considerably more difficult, as the surgical team may have difficultly placing the tube correctly. Earlier intubation and laryngeal mask airway methods cause fewer issues, but even those options come with possible complications and a high level of adverse event risk. The best option across all the studies found was generally laryngeal mask airway. Anaesthetists will have added difficulty with obese patients as the dosages do not scale correctly as body weight reaches very high levels. Using a measurement of lean body weight gives better results. Obese patients also benefit from the use of desflurane anaesthesia instead of propofol and the use of epidural anaesthesia. They need to be monitored very closely while in recovery, due to greatly lessened muscle tonicity compared to normal weight patients. Despite the many risks of surgery in the obese patient, bariatric surgery is the best option for morbidly obese patients. Traditional diet and exercise, while safer, do not have the same long-term success rates as surgical options. Bariatric surgery, in many cases, could be considered a life-saving procedure and must be performed. Therefore, it is vital that anaesthesiologists and surgeons work together to ensure the safest perioperative environment possible for the bariatric patient. Read More