In this episode of PodMD, Melbourne-based surgeon and researcher, Dr Sean Mackay will be discussing the topic of patient selection obesity surgery.
- Transcript
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*As always, all in this PodMD podcast is intended for health professionals and the comments are of a general nature. Information given is not intended as specific medical advice pertaining to any given patient. If you have a clinical issue with one of your patients please seek appropriate advice from a colleague with expertise in the area.
Today I’d like to welcome to the Pod MD studio, Sean Mackay. Sean is a hepatobiliary, upper GI and bariatric surgeon. His public appointment is at the Eastern Health where he’s a consultant surgeon at Box Hill Hospital. He’s an associate professor in the Eastern Health Clinical School, which is part of Monash University, and his private practice is based at Eastern Epworth Hospital. Sean is also one of the co-founders of Pod MD. Sean, thank you for coming in to make this odcast today.
Sean: Well, thank you for the invitation.
We do hope you enjoy this podcast but please remember that the advice here is of a general nature and is not intended as specific advice about a given patient. The views and opinions expressed in this podcast are those of the doctor, not PodMD.
If you do have a patient on whom you require specific advice then please seek advice from a colleague with appropriate expertise in that area.The topic of today’s podcast is patient selection for weight loss surgery.
Sean: Yes, that’s right, ‘d like to offer an overview of the things we consider when assessing a patient for possible weight loss surgery.
Question 1
In broad terms, what are the important considerations?Sean: Well, there are a series of things that I might just offer a short list and then we can hopefully go through them one by one. I think the first thing and the most important thing is the patient has to understand that weight loss surgery is a tool that allows the patient to change, particularly their eating behaviours and achieve sustained weight loss. But it’s not a magic wand. The patient is the one who will be limiting their calorie intake and will be losing the weight. The second thing is we look for someone who has tried diet and exercise because that indicates that they have bought into the notion that ultimately it’s on them to lose the weight. It certainly is encouraging if someone’s previously had significant weight loss, the weight might have one back on, but the fact that they’ve achieved weight loss in the past means that they can lose weight and hopefully the surgery then further facilitates that. The third thing of course, is, whatever weight the patient is and what are the comorbidities, modern surgery is very safe, but nothing is without risk in surgery and we need to balance the potential benefit for a patient versus the risk that they that they suffer from their obesity. The fourth thing is whether a given patient has any potential contraindication. There are a few things which go against the likelihood of successful surgery. We need to look for those in the assessment of the patient.
Question 2
You describe surgery as a tool for weight loss can expand on that.Sean: Of course. The major operations around these days are the sleeve gastrectomy, which is the main operation, and various forms of bypass procedure. The gastric band has almost completely died out of clinical practice at the moment. The different operations work in different ways, but fundamentally in one way or another, they designed to allow the patient to substantially decrease food intake, calorie intake and yet not to be constantly in the grip of hunger and cravings. However, if the patient is going to continue to eat in response to non hunger cues, then the calorific intake will remain high. That patient will not lose weight. So the mere fact of having an operation doesn’t mean that you can drive through McDonald’s three times a day and get a thick shake and expect to lose weight and people sometimes seem to have an unrealistic view of how powerful the surgery is.
Question 3
Carrying on from that idea, what about the prior history of diet and weight loss?Sean: Well, as we just discussed, the surgery is meant to allow the patient to diet on an ongoing basis and to lose weight. If someone has done that in the past but ultimately they’ve failed because hunger has worn them down, that’s one thing, but if surgery controls the hunger, that person seems to be well set to do well with surgery. Someone who has not had any success with diets or who hasn’t really embraced the notion of dieting, we’re a little more guarded, but that doesn’t mean they couldn’t be offered surgery. But we need to think strongly, and the Dietetic assessment would be important about what they might achieve, and perhaps that patient needs to have a period of time on a diet, and perhaps on weight loss drugs as part of the assessment.
Question 4
You mentioned the degree of obesity and the comorbidities that a person might have. Can you tell us more about that.Sean Well, as I mentioned in clinical practice the BMI is all you need most of the time, but there are two things that it doesn’t do. It doesn’t take note of the individual patients natural physical build and it doesn’t take note of the distribution of the fat within the patient’s body. And both of those things can be important.
Question 5
So to deal with the first of those, what about the patients build?Sean: Caroline, someone who is naturally fixed, set broad shouldered, broad in the hips, will naturally have a higher BMI than the average person, and so any if they do gain weight, any degree of obesity will be overestimated by the BMI. And likewise, someone who has a relatively slender build, their degree of obesity will be underestimated by the BMI. And in fact, in clinical practice there are certain definable groups in whom we have to make an adjustment. Of most relevance in Australia is people from a Southeast Asian background, and we in fact add on 2.5 BMI points for people from a Southeast Asian background, rather than adjusting those BMI cut offs of 30, 35 and 40. It’s also true in the literature and not so much of an issue in Australia, but in the American literature, that African Americans we actually take off 2 BMI points, understanding that in general that they tend to be solidly built.
Question 6
So you mentioned the distribution of fat and the pattern of the person’s obesity. Tell us more about that.Sean: Yes, of course. The classification of obesity is probably the first thing to mention. There is a separate podcast on this I won’t go into detail, but obesity is now classified by the big professional groups into classes one, two and three of obesity. Class 1 is a BMI of 30 to 35. Class 2 a BMI of 35 to 40 and Class 3 40 and above. It’s now recommended that surgery is seen as an upfront treatment for any patient with class two or three obesity and for selected patients with Class 1 obesity. In other words, patients in that BMI 30 to 35 range who may have the substantial comorbidities and in particular, a type 2 diabetes, which in fact has its own classification and will have a separate podcast on that in the works as well. The trade off, of course, is between the upfront risk of the surgery and the down the track risk of the patient’s obesity. If someone is at the lower end of the obese weight range and hasn’t really. Tried diet and exercise and it doesn’t have existing comorbidities I think it’s always attractive to see how they will do without surgery because that would be the preferred option. But on the other end of the spectrum, if someone has substantial established comorbidities and has repeatedly failed with non surgical weight loss, then we need to be, I think a little more willing than we have been as a profession to offer that patient surgery. It’s not possible to offer in a podcast detailed guidelines on any individual patient that has to be assessed by the clinicians on a case by case basis.
Question 7
At the start you did mention contraindications. Can you discuss that topic?Sean: Well, there are, I suppose 3 broad categories. The first would be the patient who’s medically compromised for major surgery due to particularly cardiovascular disease or perhaps respiratory disease. Hopefully that patient can be optimized by our physician colleagues, but we do need to remember that it’s always a balance between the upfront risk of the surgery and the down the track risk of the comorbidities and we must make sure that we don’t bring people to operating room whose risk is excessive from that operation. The second group, and this is a technical thing for the surgeons, of course is the patient with what we call a hostile abdomen. So someone who would be expected to have enormous and very difficult to dissect adhesions, perhaps because there’s been prior surgery or something else like an episode of peritonitis, and that’s perhaps especially relevant in cases of rep-operative surgery. The third group are those who’ve got significant psychiatric illness. It’s a big topic and I can’t cover it in detail here, but there’s no doubt that patients with an eating disorder and active eating disorder that’s regarded as an absolute contraindication to surgery. It doesn’t mean that the patient can’t work with their psychiatrists and then potentially come back to their surgeon but that’s a process that takes, I think, years, not weeks or months. The second group are those who might have a psychotic illness, such that there’s a potential for delusions and the risk is that the patient will in some way incorporate their surgery into their delusional belief system and that can cause enormous suffering. Those patients need to be assessed by their psychiatrist and I think that in such a case I would like to speak to the psychist. Make sure the psychiatrist understands what I think about the surgery and what surgery is like for the patient, and then undertakes to see the patient and assess them for that problem. We have operated on patients who’ve got major psychiatric illnesses, but it certainly needs a very careful approach.
Question 8
Sean, this has been a very interesting and informative discussion. Thanks again for your insights.Sean: Well, that’s a pleasure. You’re certainly very welcome.
To wrap up, could you please give us your three take home messages from today’s discussion.
Sean: Well, I think the first thing is that it’s most important that the patient has bought into the notion that the surgeon does the surgery and the patient does the hard work. To say the dieting, surgery is not magic and weight loss is not automatic. The second thing is that I think the currently accepted indications for surgery are wider than I think most of the profession appreciate at the moment, and every patient does deserve expert assessment. The third thing is that modern weight loss surgery is safe and highly effective in the right patients. And it needs to be seen as a standard treatment option, just like medications for conditions such as hypertension or diabetes or surgery for cancer. The main treatment for morbid obesity is weight loss surgery.
