202407072109
Status:
Tags: bariatric
Obesity
| Obesity Classification | BMI | BMI (Asian) |
|---|---|---|
| Class I | 30 – 34.9 | 25 - 29.9 |
| Class II | 35 – 39.9 | 30 - 34.9 |
| Class III (Morbid) | ≥ 40 | ≥ 35 |
| Morbid obesity | 40 – 49.9 | |
| Super obesity | 50 – 59.9 | |
| Super super obesity | > 60 | |
| obesity confers a chronic state of low-grade inflammation which results in metabolic derangements leading to impaired glucose utilization and increased insulin resistance |
Paed
in children, BMI varies with age and gender and it can be more appropriate to use centiles. BMI centiles can be determined using age and sex specific percentiles and interpreted in this fashion when evaluating children who are overweight and obese for appropriate treatment
BMI is a validated proxy measure of underlying adiposity that is replicable and can track weight status in children and adolescents and can be used for children >2 years old.
More than 90% of childhood obesity is due to excessive energy intake and insufficient energy expenditure; rarely, it is secondary to hormonal or genetic causes (e.g. Prader–Willi, Cushing's or Lawrence–Moon–Biedl syndromes) or use of medication (glucocorticoids, antidepressants)
Associated comorbidities
- SDB
- recurrent respiratory infections
- asthma
- hypertension
- left ventricular hypertrophy (adolescents)
- diabetes mellitus
- metabolic syndrome (central obesity, hypertension, impaired glucose tolerance, dyslipidaemia)
- GORD
- Preoperative anxiety; low self-esteem, poor school performance.
- Difficult venous access.
- Altered drug pharmacokinetics
IV drug dose in obese children
- IBW
- midazolam
- morphine
- non-depolarising NMBA
- LBW
- propofol induction
- thiopentone
- fentanyl
- remifentanil
- TBW
- propofol infusion
- suxamethonium
- sugammadex
- lignocaine
- neostigmine
IBW = (BMI at the 50th percentile for the child’s age) x (Height (m))^2
LBM (kg) = 3.8 x ECV Extracellular Volume (ECV) in litres = (0.0215) x (weight)^0.65 x (height)^0.72
Anaesthetic considerations
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Preoperative review to detect comorbidities and anticipate postoperative care requirements.
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If sedative premedication is given, dose appropriately and monitor oxygen saturations.
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Ensure adequately sized blood pressure cuff available.
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Ensure ultrasound availability for cannulation.
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Care with handling and positioning, use appropriate patient transfer equipment.
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Ensure optimal head up position for induction, adequately pre-oxygenate using PEEP, anticipate laryngoscopy and ventilation difficulties.
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Use regional anaesthetic techniques and multimodal analgesia to reduce opioid use.
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Monitor neuromuscular blockade and depth of anaesthesia.
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Extubate awake and sitting up.
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Monitor oxygen saturation continuously and give supplemental oxygen if required.
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Early mobilization and physiotherapy to reduce risk of respiratory complications and VTE.