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Fasting for general anaesthesia

  • See also

    Fasting in PICU 
     Diabetes mellitus and surgery

    Key points

    1. The goal of these guidelines is to minimise fasting times
    2. If a child appears likely to fast for longer than these times, consult anaesthetist
    3. Children with a higher risk of hypoglycaemia (diabetes mellitus, certain metabolic disorders) will have special requirements; consult anaesthetist

    Background

    • Fasting prior to anaesthesia or sedation is designed to reduce the volume of gastric contents with the aim to reduce the risk of gastric regurgitation and the consequences of any pulmonary aspiration 

    • Aspiration during anaesthesia is a rare event in children 

    • The stomach empties clear fluids in an efficient and predictable manner; a shorter period of fasting is required for clear fluids 

    Definitions of fluids and food

    Clear fluids are those which when held to light, are transparent

    Type of fluid 

    Examples 

    Time before anaesthesia 

    Clear fluids 

    Water, clear juice, RCH supplied icy pole 

    ‘Sip til Send’ 

    Sips until called to theatre 

    Breast milk 

    Breast milk 

    3 hours 

    Infant formula 

    Formula 

    4 hours 

    Food / solids 

    Cow milk, flavoured milk, smoothies, food 

    6 hours 

    Chewing gum does not significantly affect fasting but should be discarded prior to anaesthesia or sedation 

    More information on classification of fluids and food in Appendix 1 (see below)

    'Sip til Send'

    Practice that allows children to safely sip on clear fluids when they are thirsty, up until the time they are brought to pre-op hold. Children should not be forced to sip.  

    Children who are nil by mouth for medical or surgical reasons should not be offered any fluids

    Classification of fluids and food


    Clear fluids
    ‘Sip til Send’

    Breast milk
    3 hours pre-op fasting

    Infant formula
    4 hours pre-op fasting

    Food / solids
    6 hours pre-op fasting

    Water

    Breast milk

    Formula

    Cow milk, flavoured milk, smoothies, milkshakes

    Diluted cordial

    Expressed breast milk (EBM)

     

    		 Other milks eg almond, soy

    Tea/coffee without milk (includes green tea, black tea)

    EBM with fortifier

     

    		 `Tea/coffee with large amount of milk (including flat white, latte)

    Clear juice without pulp eg. Apple juice (not cloudy apple juice)

     

     

    Fruit juice with pulp eg orange, cloudy apple, freshly squeezed juice  

    Glucose based drinks eg Nutricia PreOp™, Hydralyte™, Glucose 5-10% solution, Gatorade™, Powerade™

     

     

    Thickened fluids 
    RCH supplied icy poles eg lemonade icy pole  

     

     

    Broth/soup

    Maltodextrin additive when added to a clear fluid listed above 

     

     

    Jelly

    Specific considerations

    • Oral medications should be given with clear fluids unless otherwise directed by the anaesthetist 

    • If there is a clinical concern or history consistent with increased risk of regurgitation/aspiration, consult anaesthetist 

    • Some procedures have specialised fasting plans, eg patients undergoing nuclear medicine (PET scans) or colonoscopy. Seek specific instructions 

    • Children with enteral tube or gastrostomy feeding should be fasted according to the same guidelines as other children (see above) 

    • Interruptions to enteral nutrition for children in intensive care may lead to significant calorie deficits. See Fasting in PICU 

    Acute surgery and anaesthesia

    A fasting plan should be made at the time of booking 

    For surgical emergencies, risk is balanced between surgical delay and perceived aspiration risk

    Communication    

    Information given to families and staff should be accurate and consistent            

    RCH specific information

    • Elective cases: anaesthetist for the list should be contacted first for all queries related to fasting

    • Emergency cases: after hours or when unable to contact elective list anaesthetist, phone anaesthetist in charge 

    • Deviation from ‘Sip til Send’: Individual anaesthetists choosing to vary from ‘Sip til Send’ must communicate directly with the treating team/nursing team

    Parent information

    Fasting guide

    Last updated August 2024

  • Reference List

    1. Al-Robeye A, Barnard A, Bew S. Thirsty work: Exploring children’s experiences of preoperative fasting. Pediatr Anesth. 2020;30:43-49
    2. ANZCA PG07 Guideline on pre-anaesthesia consultation and patient preparation Appendix 1 2024.
      https://www.anzca.edu.au/getattachment/897f5bf5-b665-4c99-a56f-e72678f19f7e/PG07(A)-Appendix-1-%E2%80%93-Fasting-guideline
    3. Frykholm P, et al. Pre-operative fasting in children: a guideline from the European Society of Anaesthesiology and Intensive Care, Eur J Anaesthesiol 2022; 39:4-25
    4. Joshi GP, Abdelmalak BB, Weigel WA, Harbell MW, Kuo CI, Soriano SG, et al. 2023 American Society of Anesthesiologists practice guidelines for preoperative fasting: carbohydrate-containing clear liquids with or without protein, chewing gum, and pediatric fasting duration - A modular update of the 2017 American Society of Anesthesiologists practice guidelines for preoperative fasting. Anesthesiology. 2023 Feb 1;138(2):132-151. Available from: https://pubs.asahq.org/anesthesiology/article/138/2/132/137508/2023-American-Society-ofAnesthesiologists
    5. Sydney Children’s Hospital Practice Guideline No:  2015-1042 v3. 2024: Preoperative oral fluids. Available from:  https://resources.schn.health.nsw.gov.au/policies/policies/pdf/2015-1042.pdf
    6. Zhang E, Hauser N, Sommerfield A, Sommerfield D, von Ungern-Sternberg BS. A review of pediatric fasting guidelines and strategies to help children manage preoperative fasting. Pediatr Anesth. 2023; 33: 1012-1019. doi:10.1111/pan.14738