Indian Journal of Anaesthesia  
About us | Editorial board | Search | Ahead of print | Current Issue | Past Issues | Instructions
Home | Login  | Users Online: 1660  Print this pageEmail this pageSmall font sizeDefault font sizeIncrease font size    

 Table of Contents    
Year : 2020  |  Volume : 64  |  Issue : 2  |  Page : 87-89  

Fasting for anaesthesia: Less is more!

1 Department of Anesthesiology and Critical Care, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, USA
2 Department of Anesthesia and Critical Care, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Date of Submission21-Dec-2019
Date of Decision08-Jan-2020
Date of Acceptance13-Jan-2020
Date of Web Publication4-Feb-2020

Correspondence Address:
Elizabeth M Elliott
Department of Anesthesiology and Critical Care, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ija.IJA_936_19

Rights and Permissions

How to cite this article:
Elliott EM, Isserman RS, Stricker P, Yaddanapudi S, Subramanyam R. Fasting for anaesthesia: Less is more!. Indian J Anaesth 2020;64:87-9

How to cite this URL:
Elliott EM, Isserman RS, Stricker P, Yaddanapudi S, Subramanyam R. Fasting for anaesthesia: Less is more!. Indian J Anaesth [serial online] 2020 [cited 2020 Jul 5];64:87-9. Available from:

In recent years, a large body of literature has been published questioning the dogma of fasting long durations before anaesthesia.[1],[2],[3],[4] Historically, fasting recommendations were that all patients preparing for surgery should be nil per os(NPO) from midnight prior to surgery. Guidelines from the American Society of Anesthesiologists (ASA) were first published in 1999 allowing (although not encouraging) clear fluids up until 2 hours prior to anaesthesia in response to studies that demonstrated the safety of this practice.[5] At the Children's Hospital of Philadelphia, the 2-hour clear fluid fasting policy actually resulted in children fasting for an average of 9 hours in an evaluation of 35,000 patients.[2] A similar period of fasting (average 9.5 hours) was observed in an audit of children undergoing CT scan under sedation at PGIMER, Chandigarh.[6] Other reports from different parts of the world also show prolonged duration of preoperative fasting.[7],[8],[9]

Since the first publication of the ASA guidelines in 1999, evidence has emerged on the benefit and the safety of drinking clear beverages up to 1 hour before anaesthesia for healthy children.[1],[2],[3],[4] As mentioned by Toms and Rai in the September 2019 issue,[10] a consensus statement from the European Society for Pediatric Anesthesiology (ESPA), the Association of Pediatric Anaesthetists of Great Britain and Ireland, and L'Association Des Anesthésistes-Réanimateurs Pédiatriques d'Expression Francçaise encouragesclear fluid up until 1 hour prior to anaesthesia. This statement has been endorsed by the Society for Pediatric Anaesthesia in New Zealand and Australia, the Canadian Pediatric Anesthesia Society, and the European Society for Pediatric Anesthesiology. Coinciding with a quality improvement project to decrease clear fluid fasting times and supported by evidence of the safety of shorter clear fluid fasting times, we changed our policy at Children's Hospital of Philadelphia in 2017 to a 1-hour fasting time for clear fluids. This gave our patients more opportunity to drink prior to anaesthesia and did not increase aspiration events in the 16,000 children we studied.[2] We encourage the Indian Society of Anaesthesiologists endorse similar fasting guidelines and track their aspirations rates with these changes.

Although pulmonary aspiration is a serious complication of anaesthesia, it remains a relatively uncommon event, with an incidence of 10 per 10,000 cases reported in the recent APRICOT study.[11] The vast majority of events have minor sequelae; serious complications are rare. Aspiration generally occurs in patients with other major comorbidities and risk factors, and in emergency situations.[12],[13] The guidelines published by our professional societies focus on healthy individuals having elective procedures. As such, we do not have specific recommendations to address these potentially higher-risk patients, and we are left using clinical acumen and best judgment to decide on appropriate fasting times.

One specific patient population that may benefit from a critical reassessment of feeding dogma is the critically ill patient with an endotracheal tube or a tracheostomy that are fed via post-pyloric enteral tube. Tube feeding formula itself fits into the 6-hour fast category for a light meal, infant formula and non-human milk, but fasting guidelines were created for a bolus meal, not the continuous infusion used in post-pyloric tube feeding. Of note, the ASA guidelines are based on evidence from patients without critical illness.[14] Gastric content residual from a continuous rate of feeding is likely to be significantly less than the single meal over short duration imagined by the guidelines, but data in critically ill children is sparse. Most studies of enteral tube feedings in children with endotracheal tube or tracheostomy are done within the critical care setting, rather than in the operating suite.[15],[16],[17],[18],[19],[20] Future studies are warranted to determine the safety of continuing feeds less than 6 hours prior to anaesthesia, especially if there is no airway intervention planned, and there is no intolerance of feeds.

There are many benefits to feeding patients prior to anaesthesia, especially when they are already intubated. Malnutrition in the intensive care setting can lead to loss of lean muscle mass and may contribute to infections, more ventilator days, longer ICU stay and mortality. Enteral feeding is superior to parenteral nutrition in patients able to tolerate it. In maintaining the mucosal integrity by feeding enterally, translocation of intestinal microbes may be reduced.[15],[18]

Children with burns are of special concern. Burn injury may increase metabolic requirements up to 200% of the normal, and can make it especially challenging to meet protein calorie demands when feeds are withheld for any reason.[21],[22] Burn centers regularly feed their patients during anaesthesia, especially if there is a post-pyloric tube in place. Aspiration events in these patients are exceedingly rare.[21],[22],[23] Shriner's Burns Institute in Cincinnati, USA, studied aspiration events with transpyloric feeds from 1986-1990 in 80 patients, matched for age and degree of burn injury who were either fed or fasted during surgery. There were no aspiration events in either group, and they found a significant caloric deficit and an increase in wound infections among children who were fasted during surgery.[22] There is ample evidence that actual preoperative fasting times far exceed required fasting times resulting in significant interruptions in feeds and caloric deficits.[2],[4],[7],[8],[9],[20],[24] It appears reasonable, therefore to continue post-pyloric feeds in burn patients up until, and even, during the course of surgery, provided airway or bowel manipulation are not part of the surgical plan.

As new evidence emerges regarding the safety of shortened fasting times for clear fluids in children, many national pediatric anesthesia societies are updating their fasting guidelines to reflect this data. However, recommendations may not be appropriate for all possible situations and clinical judgment remains critical for the safe practice of anaesthesia.

In light of evidence for the safety and benefit of continuing post-pyloric feeds in intubated children, we should modify our practice based on the evolution of medical knowledge.

   References Top

Andersson H, Zaren B, Frykholm P. Low incidence of pulmonary aspiration in children allowed intake of clear fluids until called to the operating suite. Paediatr Anaesth 2015;25:770-7.  Back to cited text no. 1
Isserman R, Elliott E, Subramanyam R, Kraus B, Sutherland T, Madu C, et al. Quality improvement project to reduce pediatric clear liquid fasting times prior to anesthesia. Paediatr Anaesth 2019;29:698-704.  Back to cited text no. 2
Schmidt AR, Buehler P, Seglias L, Stark T, Brotschi B, Renner T, et al. Gastric pH and residual volume after 1 and 2 h fasting time for clear fluids in children. Br J Anaesth 2015;114:477-82.  Back to cited text no. 3
Newton RJG, Stuart GM, Willdridge DJ, Thomas M. Using quality improvement methods to reduce clear fluid fasting times in children on a preoperative ward. Paediatr Anaesth 2017;27:793-800.  Back to cited text no. 4
Practice Guidelines for Preoperative Fasting and the use of Pharmacologic Agents to Reduce the Risk of Pulmonary Aspiration: Application to Healthy Patients Undergoing Elective Procedures: A Report by the American Society of Anesthesiologist Task Force on Preoperative Fasting. Anesthesiology 1999;90:896-905.  Back to cited text no. 5
Gupta A, Sen I, Bhardwaj N, Yaddanapudi S, Mathew PJ, Sahni N, et al. Prospective audit of sedation/anesthesia practices for children undergoing computerized tomography in a tertiary care institute. J Anaesthesiol Clin Pharmacol 2020 [In press]. DOI: 10.4103/joacp.JOACP_16_19.  Back to cited text no. 6
Al-Robeye AM, Barnard AN, Bew S. Thirsty work: Exploring children's experiences of preoperative fasting. Paediatr Anaesth 2020;30:43-9.  Back to cited text no. 7
Arun BG, Korula G. Preoperative fasting in children: An audit and its implications in a tertiary care hospital. J Anaesthesiol Clin Pharmacol 2013;29:88-91.  Back to cited text no. 8
[PUBMED]  [Full text]  
Beck CE, Rudolp D, Becke-Jakob K, Schindler E, Etspüler A, Trapp A, et al. Real fasting times and incidence of pulmonary aspiration in children: Results of a German prospective multicenter observational study. Paediatr Anaesth 2019;29:1040-5.  Back to cited text no. 9
Toms AS, Rai E. Operative fasting guidelines and postoperative feeding in paediatric anaesthesia-current concepts. Indian J Anaesth 2019;63:707-12.  Back to cited text no. 10
[PUBMED]  [Full text]  
Habre W, Disma N, Virag K, Becke K, Hansen TG, Jöhr M, et al. Incidence of severe critical events in paediatric anaesthesia (APRICOT): A prospective multicentre observational study in 261 hospitals in Europe. Lancet Respir Med 2017;5:412-25.  Back to cited text no. 11
Walker RW. Pulmonary aspiration in pediatric anesthetic practice in the UK: A prospective survey of specialist pediatric centers over a one-year period. Paediatr Anaesth 2013;23:702-11.  Back to cited text no. 12
Warner MA, Warner ME, Warner DO, Warner LO, Warner EJ. Perioperative pulmonary aspiration in infants and children. Anesthesiology 1999;90:66-71.  Back to cited text no. 13
Practice Guidelines for Preoperative Fasting and the Use of Pharmacologic Agents to Reduce the Risk of Pulmonary Aspiration: Application to Healthy Patients Undergoing Elective Procedures: An Updated Report by the American Society of Anesthesiologists Task Force on Preoperative Fasting and the Use of Pharmacologic Agents to Reduce the Risk of Pulmonary Aspiration. Anesthesiology 2017;126:376-93.  Back to cited text no. 14
Brown AM, Carpenter D, Keller G, Morgan S, Irving SY. Enteral nutrition in the PICU: Current status and ongoing challenges. J Pediatr Intensive Care 2015;4:111-20.  Back to cited text no. 15
Fineman LD, LaBrecque MA, Shih MC, Curley MA. Prone positioning can be safely performed in critically ill infants and children. Pediatr Crit Care Med 2006;7:413-22.  Back to cited text no. 16
Fremont RD, Rice TW. How soon should we start interventional feeding in the ICU? Curr Opin Gastroenterol 2014;30:178-81.  Back to cited text no. 17
Mehta NM. Approach to enteral feeding in the PICU. Nutr Clin Pract 2009;24:377-87.  Back to cited text no. 18
Schneider JA, Lee YJ, Grubb WR, Denny J, Hunter C. Institutional practices of withholding enteral feeding from intubated patients. Crit Care Med 2009;37:2299-302.  Back to cited text no. 19
Segaran E, Barker I, Hartle A. Optimising enteral nutrition in critically ill patients by reducing fasting times. J Intensive Care Soc 2016;17:38-43.  Back to cited text no. 20
Imeokparia F, Johnson M, Thakkar RK, Giles S, Capello T, Fabia R. Safety and efficacy of uninterrupted perioperative enteral feeding in pediatric burn patients. Burns 2018;44:344-9.  Back to cited text no. 21
Jenkins ME, Gottschlich MM, Warden GD. Enteral feeding during operative procedures in thermal injuries. J Burn Care Rehabil 1994;15:199-205.  Back to cited text no. 22
Varon DE, Freitas G, Goel N, Wall J, Bharadia D, Sisk E, et al. Intraoperative feeding improves calorie and protein delivery in acute burn patients. J Burn Care Res 2017;38:299-303.  Back to cited text no. 23
Pham CH, Collier ZJ, Webb AB, Garner WL, Gillenwater TJ. How long are burn patients really NPO in the perioperative period and can we effectively correct the caloric deficit using an enteral feeding “Catch-up” protocol? Burns 2018;44:2006-10.  Back to cited text no. 24


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article

 Article Access Statistics
    PDF Downloaded283    
    Comments [Add]    

Recommend this journal