Gastric sleeve surgery — also called laparoscopic sleeve gastrectomy — is the most commonly performed weight loss operation in Australia. It is highly effective, well tolerated, and produces life-changing results for the right patients. But is it right for you?
This is one of the most important questions in bariatric surgery — and it deserves a thorough, honest answer. Not everyone who wants gastric sleeve surgery is the best candidate for it, and not everyone who qualifies medically is ready for it psychologically and practically.
Dr Devesh Kaushal is an upper GI, bariatric, and general surgeon consulting at 4 Hyde Parade, Campbelltown. In this guide, he walks through the complete eligibility criteria for gastric sleeve surgery — including BMI thresholds, health conditions, lifestyle requirements, and factors that may mean a different approach is better suited to you.
Campbelltown Consulting Rooms | 4 Hyde Parade, Campbelltown NSW 2560 Appointments within 4–8 weeks | Book online at drdeveshkaushal.com.au | Call (02) 7906 8312 |
Why Eligibility Criteria Exist — and Why They Matter
Gastric sleeve surgery is a permanent, irreversible operation that carries real surgical risks. The eligibility criteria that exist for bariatric surgery are not arbitrary bureaucratic hurdles — they represent decades of clinical evidence about which patients benefit most, which patients face unacceptable surgical risk, and which patients are genuinely ready to commit to the lifelong lifestyle changes that make weight loss surgery successful.
Understanding these criteria helps you approach your consultation with realistic expectations. It also helps you identify — honestly — whether you are ready for this step or whether further preparation is needed first.
BMI Criteria: The Starting Point
Body Mass Index (BMI) is the primary numerical threshold used to assess eligibility for gastric sleeve surgery. BMI is calculated from your height and weight — it is an imperfect measure, but it is widely used as a practical screening tool.
BMI ≥ 40 Eligible | A BMI of 40 or above qualifies for gastric sleeve surgery regardless of whether you have other health conditions. At this BMI, the metabolic and health risks of ongoing obesity are well established, and the benefits of surgical weight loss reliably outweigh the surgical risk. |
BMI 35–39.9 Eligible with conditions | A BMI between 35 and 40 qualifies for gastric sleeve surgery when accompanied by at least one significant obesity-related health condition — such as type 2 diabetes, obstructive sleep apnoea, hypertension, osteoarthritis, fatty liver disease (NASH), or PCOS. The health condition must be documented and ideally under active management. |
BMI 30–34.9 Selected cases only | A BMI between 30 and 35 is generally below the standard threshold for sleeve gastrectomy. However, in patients with poorly controlled type 2 diabetes, metabolic syndrome, or severe sleep apnoea where non-surgical approaches have failed, surgery may be considered in selected cases. This requires careful individual assessment and multidisciplinary review. |
BMI < 30 Not eligible | Gastric sleeve surgery is not appropriate for patients with a BMI below 30. Non-surgical weight management — dietary, lifestyle, and pharmacological approaches — remains the appropriate pathway at this BMI. |
Obesity-Related Health Conditions That Support Eligibility
For patients with a BMI between 35 and 40, the presence of one or more of the following conditions strengthens the case for surgical treatment — both by qualifying you for surgery and by demonstrating that weight loss surgery will produce significant health benefits beyond weight alone:
Condition | Why It Supports Eligibility | Expected Outcome Post-Surgery |
Type 2 Diabetes | Strongest weight-loss surgery indication — diabetes remission is a primary goal | 60–80% remission rate |
Sleep Apnoea (OSA) | Obesity is the primary driver — weight loss produces dramatic improvement | Up to 85% improvement/resolution |
Hypertension | Excess weight drives elevated blood pressure — often resolves with weight loss | 60–75% improvement |
Fatty Liver (NASH) | Weight loss is the only proven treatment for NASH — surgery produces rapid improvement | Significant improvement |
PCOS | Insulin resistance is central — weight loss restores hormonal function | Hormonal normalisation, fertility improvement |
Osteoarthritis | Reduced joint load produces major symptom improvement | Significant pain reduction |
GORD / Acid Reflux | Note: sleeve may worsen GORD — discuss carefully. Bypass may be preferred. | Variable — discuss with Dr Kaushal |
Depression / Anxiety | Obesity-related depression improves with weight loss — but psychological clearance needed | Often improves with weight loss |
Lifestyle Readiness: Are You Truly Ready for Surgery?
BMI and health conditions determine whether you qualify medically for gastric sleeve surgery. But equally important is whether you are ready practically and psychologically for what surgery requires. Dr Kaushal considers the following at every bariatric consultation:
Previous weight loss attempts:
Have you genuinely tried to lose weight through diet, lifestyle change, and potentially medication — without achieving durable long-term results? Gastric sleeve surgery is not a first-line treatment — it is recommended for patients who have not been able to sustain meaningful weight loss through non-surgical means. This is both a clinical requirement and an important reflection of the role surgery plays: it is a powerful tool, but it still requires lifestyle change to work.
Understanding the commitment required:
Gastric sleeve surgery is a tool — not a cure. The operation creates the conditions for significant weight loss, but it does not do the work for you. Long-term success requires:
- Permanent changes to eating habits — smaller portions, slower eating, high-protein focus
- Lifelong daily vitamin and mineral supplementation — iron, calcium, vitamin D, B12, multivitamin
- Regular physical activity — building toward 150 minutes of moderate exercise per week
- Lifelong follow-up appointments — 1 month, 3 months, 6 months, 12 months, then annually
- Willingness to seek support — from dietitian, psychologist, and support groups as needed
- Commitment to avoid pregnancy for at least 18 months post-surgery
Honest self-reflection: Before your consultation, ask yourself honestly: Am I ready to change how I eat permanently? Am I willing to take supplements every day for the rest of my life? Will I attend follow-up appointments? These are not trick questions — they are the questions that determine whether surgery produces life-changing results or disappointing ones. |
Who May Not Be Suitable for Gastric Sleeve Surgery?
Not every patient who wants gastric sleeve surgery is the best candidate for it. The following factors may mean that surgery is contraindicated, needs to be deferred, or that a different procedure is more appropriate:
Medical contraindications:
- Severe, uncontrolled gastro-oesophageal reflux disease (GORD) or significant hiatus hernia — sleeve may worsen reflux. Gastric bypass may be preferable.
- Barrett’s oesophagus — pre-cancerous change in the oesophagus is a relative contraindication for sleeve due to acid exposure risk.
- Large or complex hiatus hernia requiring simultaneous repair
- Severe, uncontrolled inflammatory bowel disease
- Active malignancy or recent cancer treatment (within 5 years in most cases)
- Significant liver disease — cirrhosis increases surgical risk substantially
- Uncontrolled serious cardiac or respiratory disease that makes anaesthesia unsafe
- Pregnancy — surgery is deferred until after delivery and a minimum period of breastfeeding
Psychological and lifestyle contraindications:
- Active, untreated substance use disorder — alcohol or drug dependency requires treatment first
- Severe, untreated psychiatric illness that has not been assessed and stabilised
- Binge eating disorder that has not been addressed — surgery alone does not resolve binge eating and outcomes are significantly worse
- No clear understanding of or commitment to the required lifestyle changes
- Unwillingness to attend follow-up or take lifelong supplements
Important: Several of these factors are modifiable — meaning surgery can proceed once the condition is addressed. Active smoking, for example, significantly increases surgical risk but quitting before surgery makes the procedure much safer. Dr Kaushal will advise you on what needs to be optimised before surgery can safely proceed. |
When Gastric Bypass May Be Recommended Instead of Sleeve
Gastric sleeve is the most commonly chosen bariatric procedure — but it is not right for everyone. Dr Kaushal may recommend gastric bypass (Roux-en-Y gastric bypass) instead of sleeve in the following situations:
Significant GORD or hiatus hernia: Sleeve gastrectomy can worsen acid reflux in susceptible patients due to increased pressure in the narrowed stomach. Gastric bypass diverts stomach acid away from the oesophagus and typically improves rather than worsens reflux. |
Barrett’s oesophagus: The chronic acid exposure risk associated with sleeve is a significant concern in Barrett’s patients. Bypass is preferred in most cases. |
Very high BMI (over 50): Although sleeve produces excellent results across all BMI ranges, bypass may produce slightly greater and more sustained weight loss at very high BMI — and offers stronger metabolic effect in patients with severe diabetes. |
Type 2 diabetes as primary indication: Gastric bypass produces the highest diabetes remission rates of any bariatric procedure. For patients where diabetes control is the primary goal, bypass may be recommended. |
Previous sleeve with inadequate weight loss: If a patient has had a gastric sleeve and not achieved sufficient weight loss or has regained weight, conversion to gastric bypass is an effective revision option. |
Pre-Operative Assessment: What Happens Before Surgery Is Approved
Once Dr Kaushal has assessed your eligibility at consultation, a comprehensive pre-operative assessment is arranged before surgery is confirmed. This ensures you are fully optimised for the safest possible outcome:
- Blood tests: Full blood count, metabolic panel, liver function, thyroid, HbA1c, iron studies, B12, vitamin D, lipid profile, and coagulation screen.
- Gastroscopy: An endoscopy is performed before bariatric surgery to assess the oesophagus and stomach for conditions that may affect the choice of procedure — particularly GORD, hiatus hernia, Barrett’s oesophagus, H. pylori infection, and gastric ulcers.
- Sleep study: If obstructive sleep apnoea is suspected or known, a formal sleep study confirms the diagnosis and guides whether CPAP treatment is needed before surgery.
- Cardiac assessment: ECG and cardiac review as needed based on age, symptoms, and risk factors.
- Dietitian assessment: A consultation with a bariatric dietitian assesses your current diet, eating behaviours, and readiness to commit to the required dietary changes. The pre-operative liver-shrinking diet is also explained.
- Psychological assessment: A psychological evaluation assesses readiness, motivation, eating patterns, and mental health. This is not a test to pass or fail — it is designed to identify any areas where additional support before or after surgery will improve outcomes.
- Smoking cessation: Active smokers are strongly advised to stop at least 6 to 8 weeks before surgery. Smoking significantly increases anaesthetic risk, wound healing problems, staple line complications, and post-operative chest infections.
- Pre-operative liver-shrinking diet: A 2-week high-protein, low-carbohydrate diet is required before surgery. This shrinks the liver — which sits directly over the stomach — making the operation safer and technically easier to perform.
What Happens at Your First Consultation in Campbelltown?
Your first appointment with Dr Kaushal at 4 Hyde Parade, Campbelltown is an unhurried, thorough consultation. Here is what to expect:
- Dr Kaushal reviews your full medical history, current medications, obesity-related health conditions, weight history, and previous weight loss attempts
- Your BMI is confirmed and the specific eligibility criteria relevant to your case are discussed
- The gastric sleeve procedure is explained in detail — what happens during surgery, the expected results, the required lifestyle changes, and the risks
- Any factors that may make sleeve less suitable — such as significant reflux — are identified and discussed
- Alternative procedures are presented if relevant
- The pre-operative assessment pathway is outlined
- All your questions are answered — no question is too small or too basic
- You leave with written information and a clear plan for next steps — without any pressure to proceed
What to bring to your consultation: ✔ GP referral letter — required for Medicare rebates ✔ Medicare card and private health insurance card ✔ List of current medications and any allergies ✔ Any recent blood test results or previous medical investigations ✔ Your weight history — maximum weight, current weight, previous attempts at weight loss ✔ A list of questions you want answered |
Quick Self-Assessment: Are You Likely to Qualify?
Answer the following questions honestly. If you answer yes to the criteria shown, you are likely to qualify for a consultation assessment — and Dr Kaushal will determine the final answer based on your full history and examination.
Question | Yes | No |
Is your BMI 40 or above? | ☐ | ☐ |
Is your BMI 35–40 AND do you have type 2 diabetes, sleep apnoea, high blood pressure, or another obesity-related condition? | ☐ | ☐ |
Have you tried to lose weight through diet and lifestyle changes without lasting success? | ☐ | ☐ |
Are you aged between 18 and 65? | ☐ | ☐ |
Are you willing to commit to permanent dietary changes after surgery? | ☐ | ☐ |
Are you willing to take daily vitamin supplements for life? | ☐ | ☐ |
Are you free from active substance dependency? | ☐ | ☐ |
Is your obesity-related health condition affecting your quality of life? | ☐ | ☐ |
If you answered YES to most of these questions, you are very likely to qualify for a gastric sleeve consultation with Dr Kaushal. The only way to get a definitive answer is a consultation at the Campbelltown rooms — where Dr Kaushal can assess your individual circumstances in full. |
Frequently Asked Questions — Gastric Sleeve Eligibility Campbelltown
What BMI do I need for gastric sleeve surgery in Australia?
The standard BMI thresholds are: BMI of 40 or above regardless of other conditions, or BMI of 35 to 39.9 with at least one significant obesity-related health condition such as type 2 diabetes, sleep apnoea, or hypertension. Selected patients with BMI 30–35 and poorly controlled diabetes may also be considered. Dr Kaushal assesses eligibility based on your complete health picture — not BMI alone.
Does my age affect whether I can have gastric sleeve surgery?
Adults aged 18 to 65 are the primary candidate group. Patients over 65 are assessed individually — age alone is not a disqualifier, but surgical risk increases with age and multiple health conditions. Patients under 18 are not offered bariatric surgery at this service. For patients aged 60 to 65, a careful discussion of risk versus benefit is particularly important.
I have bad reflux — can I still have a gastric sleeve?
Significant pre-existing reflux (GORD) or a hiatus hernia is an important factor that needs careful assessment before choosing gastric sleeve. Sleeve gastrectomy can worsen reflux in susceptible patients. If you have significant reflux, Dr Kaushal will perform a gastroscopy as part of your pre-operative assessment, and may recommend gastric bypass as a more appropriate alternative. This is discussed openly at consultation.
Do I need to have tried diets before I can have gastric sleeve surgery?
Yes — in both a clinical and practical sense. The eligibility criteria require documentation of previous attempts at sustained weight loss through lifestyle approaches. More importantly, surgery produces the best results in patients who have genuinely engaged with dietary and lifestyle change — because the habits developed before surgery become the foundation for success after it. Dr Kaushal does not require a specific number of failed diet attempts, but will assess your weight loss history at consultation.
Can I have a gastric sleeve if I have depression or anxiety?
Mental health conditions do not automatically disqualify you from bariatric surgery. However, active, severe, or untreated psychiatric illness requires assessment and stabilisation before surgery. A psychological evaluation is part of the standard pre-operative assessment and is designed to identify any areas where additional support will improve your long-term outcomes — not to exclude patients with mental health conditions.
How do I find out if I qualify — and how do I book in Campbelltown?
The most reliable way to find out if you qualify is a consultation with Dr Kaushal at 4 Hyde Parade, Campbelltown NSW 2560. Book online at drdeveshkaushal.com.au or call (02) 7906 8312. You will need a GP referral for Medicare rebates. Appointments are available within 4 to 8 weeks.
Ready to Find Out If You Qualify? Book in Campbelltown Today
If you have been living with obesity and its health consequences, and are wondering whether gastric sleeve surgery is right for you — the next step is a consultation. Dr Devesh Kaushal provides honest, thorough bariatric surgical assessment at his Campbelltown rooms for patients across the Macarthur region.
In one appointment, you will receive a clear answer on whether you qualify, which procedure is most appropriate, what the process looks like, what results you can realistically expect — and what it will cost. No pressure. No commitment. Just the information you need to make the right decision.
Contact Dr Devesh Kaushal Campbelltown Consulting Rooms 4 Hyde Parade, Campbelltown NSW 2560 Phone: (02) 7906 8312 Email: [email protected] Book Online: drdeveshkaushal.com.au Office Hours: Monday – Friday, 9:00 AM – 5:00 PM Operating at: Sydney Southwest Private Hospital Liverpool | Campbelltown Public Hospital | Campbelltown Private Hospital | The George Hospital Appointments available within 4–8 weeks depending on urgency | Book online 24/7 | Medicare & Private Health Insurance Accepted |
Expert bariatric surgery assessment — available to Campbelltown and Macarthur region patients at 4 Hyde Parade, Campbelltown NSW 2560.
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