The evidence comparing fasting with protein-containing clear liquids in adults was limited to single trials for each patient-reported outcome (table 4). Preoperative nil per os (NPO) guidelines have been in existence since the recognition of the risk of perioperative aspiration. Consistent with the 2017 ASA guideline intended population,1 healthy individuals are defined as those without coexisting diseases or conditions that may increase the risk for aspiration, including esophageal disorders such as significant uncontrolled reflux disease, hiatal hernia, Zenkers diverticulum, achalasia, stricture; previous gastric surgery (for example, gastric bypass); gastroparesis; diabetes mellitus88,89; opioid use; gastrointestinal obstruction or acute intraabdominal processes; pregnancy; obesity; and emergency procedures.24 Anesthesiologists should recognize that these conditions can increase the likelihood of regurgitation and pulmonary aspiration and should modify these guidelines based upon their clinical judgment. 1 Clear liquids include water, tea, black coffee, pulp-free juice, and carbohydrate-rich drinks. To evaluate potential publishing bias, a fail-safe n value was calculated. Effects of preoperative carbohydrates drinks on immediate postoperative outcome after day care laparoscopic cholecystectomy. Differences were not detected in patient-reported hunger or thirst, incidence of aspiration or regurgitation, and gastric pH among pediatric patients fasting for 1h compared with 2h (table 7). Evaluation of effects of a preoperative 2-hour fast with glutamine and carbohydrate rich drink on insulin resistance in maxillofacial surgery. An acceptable significance level was set at P< 0.01 (one-tailed). 6. buick lacrosse for sale under $10,000. In the carbohydrate arms, liquids were allowed an average of 2.25h before surgery (80% until 2h). However, only the findings obtained from formal surveys are reported in the current update. Influence of preoperative fasting time on maternal and neonatal blood glucose level in elective caesarean section under subarachnoid block. The guideline topics were approved by the Guidelines Committee and the ESAIC Board after a consultation process within the subcommittees of the ESAIC Scientific Committee. Gastric residual volume by magnetic ressonance after intake of maltodextrin and glutamine: A randomized double-blind, crossover study. Braz J Anesthesiol (English Edition). Editorials, letters, and other articles without data were excluded. It is illegal to commercially import or sell smokeless tobacco products in Australia - this includes oral snuff, tobacco paste and powder and chewing tobacco. colonel frank o'sullivan interview; beverly hills high school football A carbohydrate-rich beverage prior to surgery prevents surgery-induced immunodepression: A randomized, controlled, clinical trial. The term gastroesophageal reflux disease refers to positional reflux and its consequent symptomology, rather than food intolerances (e.g., tomatoes do not agree with me). Pre-operative intravenous co-administration of ranitidine and metoclopramide: effect on gastric content in laparascopic cholecystectomy. Category B: Membership Opinion. The literature relating to seven evidence linkages contained enough studies with well-defined experimental designs and statistical information to conduct formal meta-analyses. Welcome! The outcomes of interest for this update include the adverse consequences of fasting (hunger, thirst, and preoperative nausea and vomiting) and pulmonary aspiration. (Chair). Effects of preoperative oral carbohydrate therapy on perioperative glucose metabolism during oralmaxillofacial surgery: Randomised clinical trial. This current update consists of a literature evaluation and an update of the evidence-based guideline nomenclature. In addition, practice guidelines developed by the American Society of Anesthesiologists (ASA) are not intended as standards or absolute requirements, and their use cannot guarantee any specific outcome. Is fasting duration important in post adenotonsillectomy feeding time? For each key question, the evidence synthesis and summary tables of benefits and harms were presented to the task force. The updated searches covered a 6.5-yr period from January 1, 2010, through May 31, 2016. The mean age of participants was 43.2 yr, and 64% were female. Search for other works by this author on: Address correspondence to American Society of Anesthesiologists: 1061 American Lane, Schaumburg, Illinois 60173. Actively encouraging clear liquids in healthy children as close to 2h before procedures as possible is important to avoid them. Guidelines to the practice of anesthesia Revised edition 2022. A randomized placebo controlled trial of preoperative carbohydrate drinks and early postoperative nutritional supplement drinks in colorectal surgery. American Society of Anesthesiologists Committee. About Us; Staff; Camps; Scuba. The task force reaffirms the previous recommendations for clear liquids until 2h preoperatively. Preanesthetic cimetidine and metoclopramide for acid aspiration prophylaxis in elective surgery. Safety and benefit of pre-operative oral carbohydrate in infants: A multi-center study in China. All protein-containing clear liquids also contained carbohydrates. 17, https://links.lww.com/ALN/C935) or gastric pH46,50,51,69,71 after fasting or drinking carbohydrate-containing clear liquids (moderate strength of evidence). Titles with abstracts and full-text screening were performed using systematic review software (DistillerSR,9 Evidence Partners, Ottawa, Canada). The evidence suggests there is not a clinically meaningful increase in gastric volume after chewing gum. Chewing gum, sucking hard candy on the morning of surgery may stimulate . 1 Smokeless Tobacco and Oral Disease Smokeless tobacco can cause white or gray patches inside the mouth (leukoplakia) that can lead to cancer. 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. Supplemental digital content is available for this article. Inadequate literature cannot be used to assess relationships among clinical interventions and outcomes because a clear interpretation of findings is not obtained due to methodological concerns (e.g., confounding of study design or implementation) or the study does not meet the criteria for content as defined in the Focus of the guidelines. Exclusion criteria (except to obtain new citations): For the systematic review, potentially relevant clinical studies were identified via electronic and manual searches of the literature. The body of evidence included 139 studies (adult surgical: 99 randomized controlled trials,2334,3664,6886,91,118157 7 nonrandomized trials,65,66,87,152,158160 3 prospective cohort studies,90,161,162 2 retrospective cohort studies,163,164 1 case-control study,165 and 2 beforeafter studies67,166; adult nonsurgical: 1 randomized controlled trial,167 9 crossover,168176 and 2 nonrandomized trials177,178; pediatric surgical: 9 randomized controlled trials,100,113,179185 1 prospective cohort186; and pediatric nonsurgical: 2 randomized controlled trial,102,104 1 crossover,35 and 1 prospective cohort103) comparing carbohydrate-containing clear liquids (simple, complex) with water, placebo, or fasting. Additional fasting time (e.g., 8 or more hours) may be needed in cases of patient intake of fried foods, fatty foods, or meat. Comparisons and questions of interest include, Carbohydrate-containing clear liquids (simple and complex) compared with fasting and noncaloric clear liquids, Simple carbohydratecontaining clear liquids compared with complex carbohydratecontaining clear liquids, Carbohydrate-containing clear liquids (simple and complex) compared with clear protein-containing liquids alone, Protein-containing clear liquids alone compared with fasting and other clear liquids, Adding milk or cream to coffee or tea versus fasting and other clear liquids, The impact of carbohydrate-containing clear liquids on glycemic levels in patients with diabetes, There is a need for studies evaluating gastric volume, gastric emptying, and aspiration in patients with high risk of regurgitation. CINeMA: An approach for assessing confidence in the results of a network meta-analysis. The results were then summarized in tabular form by outcome. Because gum chewing and 1-h fasting in pediatric patients were new in this guideline, studies published beginning in January 1990 were eligible. The purposes of these guidelines are to provide direction for clinical practice related to preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration and to reduce the severity of complications related to perioperative pulmonary aspiration. Fasting Guidelines. Randomized clinical trial comparing an oral carbohydrate beverage with placebo before laparoscopic cholecystectomy. A light meal or nonhuman milk may be ingested for up to 6 h before elective procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia.. The authors declare no competing interests. When the relevant data were not reported in the published work, attempts were made to contact the authors. Trial participants ingested a median of 400ml of carbohydrate-containing clear liquids (interquartile range, 300 to 400ml) up to 2h before anesthesia administration. All Rights Reserved. Fluid deprivation before operation. NPO Guidelines NPO Guidelines Guidelines for Adults and Teenagers Adults and teenagers over the age of 12 may have solid foods and dairy products until 8 hours before their scheduled arrival time at the hospital or surgery center. Medications that block gastric acid secretion may be preoperatively administered to patients at increased risk of pulmonary aspiration. Outcomes: adverse effects of fasting (preoperative hunger, thirst, and nausea) and pulmonary aspiration. Rigorous comparisons for equivalence or superiority between 1-h versus 2-h fasting durations in pediatric patients are needed. Furthermore, it would be necessary to update related policies, printed literature, and wall posters/charts to ensure that patients are receiving consistent messages and instructions from all medical personnel. The intended population for this update is the same as for the 2017 ASA guideline, limited to healthy patients undergoing elective procedures.1 Healthy patients are those without coexisting diseases or conditions that may increase the risk for aspiration, including esophageal disorders such as significant uncontrolled reflux disease, hiatal hernia, Zenkers diverticulum, achalasia, stricture; previous gastric surgery (for example, gastric bypass); gastroparesis; diabetes mellitus; opioid use; gastrointestinal obstruction or acute intraabdominal processes; pregnancy; obesity; and emergency procedures.24 Anesthesiologists should recognize that these conditions can increase the likelihood of regurgitation and pulmonary aspiration and should modify these guidelines based upon clinical judgment. I doubt I could have made it even these four days without a IF lead in. Antacids may be preoperatively administered to patients at increased risk of pulmonary aspiration. Preoperative carbohydrate loading in patients undergoing coronary artery bypass or spinal surgery. scented chewing tobacco (tobacco with added flavours) naswar, nas, niswar (tobacco with slaked lime, indigo, cardamom, oil, menthol, water) chillam (heated tobacco) paan (tobacco, areca. First, the Task Force reached consensus on the criteria for evidence. Complications of aspiration include, but are not limited to, aspiration pneumonia, respiratory compromise, and related morbidities. Safe pre-operative fasting times after milk or clear fluid in children. 1 Smokeless tobacco can cause gum disease, tooth decay, and tooth loss. Preparation of these guidelines followed a rigorous methodological process. appropriate fasting period. Aspiration pneumonitis and aspiration pneumonia. Effects of preoperative oral carbohydrate on cirrhotic patients under endoscopic therapy with anesthesia: A randomized controlled trial. Comparative trial of the effect of ranitidine and cimetidine on gastric secretion in fasting patients at induction of anaesthesia. Advise tobacco users to quit. Second, original published research studies from peer-reviewed journals relevant to preoperative fasting and pulmonary aspiration were reviewed and evaluated. Previous ASA guidelines recommend that clear liquids such as water, black coffee, black tea, and juice without pulp are safe to drink until 2h before general anesthesia, regional anesthesia, or procedural sedation for elective procedures.1. Paediatric glucose homeostasis during anaesthesia. Anesthesiology 2023; 138:132151 doi: https://doi.org/10.1097/ALN.0000000000004381. Effects of preoperative carbohydrate loading on glucose metabolism and gastric contents in patients undergoing moderate surgery: A randomized, controlled trial. According to the American Lung Association, chewing tobacco contains at least 28 chemicals that can lead to various illnesses, including mouth, esophageal, and pancreatic cancers, gum disease, and tooth decay and loss. Gastric emptying abnormalities in diabetes mellitus. Anesthesiology, V 126 No 3 376 March 2017: 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 In addition, findings from both the Fisher and weighted Stouffer combined tests must agree with each other. Differences were not detected in rates of nausea36,39,4345 (low strength of evidence) or patient-rated nausea (low strength of evidence). In this framework, randomized control trials start as high strength of evidence, and nonrandomized studies start as low. Both the consultants and ASA members agree that for infants, fasting from the intake of nonhuman milk for 6 or more hours before elective procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia should be maintained. asa npo guidelines 2020 chewing tobacco. Effects of a preoperative carbohydrate-rich drink before ambulatory surgery: A randomized controlled, double-blinded study. Pre-operative carbohydrate loading prior to elective caesarean delivery: A randomised controlled trial. Studies with multicomponent interventions (for example, enhanced recovery after surgery protocols) were excluded if the effect of fasting on outcomes could not be independently ascertained. The effects of preoperative carbohydrate loading on the metabolic response to surgery in a low resource setting. Are you thirsty?Fasting times in elective outpatient pediatric patients. appropriate fasting period. Randomized trial comparing overnight preoperative fasting period. Home. Pre-operative oral carbohydrate treatment before coronary artery bypass surgery. Randomized controlled trial of preoperative oral carbohydrate treatment in major abdominal surgery. The body of evidence was first described according to study characteristics and treatment arms. Key Points. GRADE guidelines: 15. Ninety-six percent of the respondents indicated that the guidelines would have no effect on the amount of time spent on a typical case. There is no clinically relevant increase in residual gastric volume after chewing gum92,9497 (low strength of evidence, supplemental fig. Age limits It is illegal to sell or supply tobacco products to young people under the age of 18. Oral rehydration solutions were classified as simple carbohydrates. Anesthesiology 2013; 118:291307. There is insufficient evidence concerning benefits and harms to recommend pediatric patients drink clear liquids until 1h versus 2h before procedures with general anesthesia, regional anesthesia, or procedural sedation (no recommendation). Patients chewing gum had a minimally increased residual gastric volume at anesthesia induction compared with fasting (table 6). Most patients in the studies were ASA Physical Status I or II with mean or median body mass index of 25kg/m2 (range, 21 to 33kg/m2; see Appendix). Six additional studies provided data on gastric volume over time.35,102-106 Three of the studies102104 were consistent with a return to baseline gastric volume close to 2h, while three studies35,105,106 were consistent with a return at 1h (very low strength of evidence; supplemental table 20, https://links.lww.com/ALN/C934). Effects of 2-, 4- and 12-hour fasting intervals on preoperative gastric fluid pH and volume, and plasma glucose and lipid homeostasis in children. The effect of preoperative oral carbohydrate or oral rehydration solution on postoperative quality of recovery: A randomized, controlled clinical trial. Seventh, all available information was used to build consensus within the Task Force to finalize the updated guidelines. When available, Category A evidence is given precedence over Category B evidence for any particular outcome. The effect of a small drink. The consultants agree and the ASA members strongly agree that for otherwise healthy neonates (< 44 gestational weeks) and infants, fasting from the intake of breast milk for 4 or more hours before elective procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia should be maintained. Effects of preoperative oral carbohydrates and trace elements on perioperative nutritional status in elective surgery patients. Safety of oral glutamine in the abbreviation of preoperative fasting: A double-blind, controlled, randomized clinical trial. The use of gastrozepin as a prophylaxis against pulmonary acid aspiration: a new muscarinic receptor antagonist. Comfort, safety and quality of upper gastrointestinal endoscopy after 2 hours fasting: A randomized controlled trial. Cochrane Bias Methods Group, Cochrane Statistical Methods Group. Both the consultants and ASA members agree that for neonates and infants, fasting from the intake of infant formula for 6 or more hours before elective procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia should be maintained. Effects of preoperative oral carbohydrate loading on preoperative and postoperative comfort in patients planned to undergo elective cholecystectomy: A prospective randomized controlled clinical trial. Mixed treatment comparisons did not support the superiority of complex carbohydrates over simple carbohydrates with respect to residual gastric volume or hunger (network meta-analysis; supplemental figs. Effect of low-concentration carbohydrate on patient-centered quality of recovery in patients undergoing thyroidectomy: A prospective randomized trial. For example, a rapid-sequence induction/endotracheal intubation technique or awake endotracheal intubation technique may be useful to prevent this problem during the delivery of anesthesia care. The role of H2 receptor antagonist premedication in pregnant day care patients. This guide was updated in . All other recommendations from the 2017 guideline still apply. Anesthesiologists and other anesthesia providers should recognize that these conditions can increase the likelihood of regurgitation and pulmonary aspiration, and that additional or alternative preventive strategies may be appropriate. The addition of protein to preoperative carbohydrate-containing clear liquids did not seem to either benefit or harm healthy patients. Aspiration,49,53,55,57,80 regurgitation,55,68 and preoperative vomiting85 were not reported in any studies comparing protein-containing clear liquids with noncaloric clear liquids. Complications associated with anaesthesiaa prospective survey in France. However, if a patient chews gum for personal comfort or preference, we recommend not delaying the scheduled elective procedure, due to inconclusive evidence of harm. Total hip arthroplasty and perioperative oral carbohydrate treatment: A randomised, double-blind, controlled trial. A carbohydrate-rich drink reduces preoperative discomfort in elective surgery patients. Level 2: The literature contains noncomparative observational studies with associative statistics (e.g., relative risk, correlation, sensitivity and specificity). Gastric fluid volume and pH after fentanyl, enflurane, or halothane-nitrous oxide anesthesia with or without atropine or glycopyrrolate. Impact of enhanced recovery after surgery with preoperative whey protein-infused carbohydrate loading and postoperative early oral feeding among surgical gynecologic cancer patients: An open-labelled randomized controlled trial. The consultants agree and the ASA members strongly agree that fasting from the intake of a light meal ( e.g ., toast and a clear liquid) of 6 or more hours before elective procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia should be maintained. Industry support was reported in 16 trials, and author conflict of interest was reported in 12 (10%) studies. Practice guidelines are subject to revision as warranted by the evolution of medical knowledge, technology, and practice. Gastric residual volume in infants and children following a 3-hour fast. They also strongly agree that patients should be informed of fasting requirements and the reasons for them sufficiently in advance of their procedures. mjk funeral home obituaries; san jose state university graduate programs deadlines Men umschalten. 8,061. About the Guidelines The Guidelines Committee has established several task forces to elaborate guidelines on the related subject. Comparators of interest include, Carbohydrate- and protein-containing clear liquids alone and in combination. No differences in the occurrence of regurgitation were detected. All opinion-based evidence (e.g., survey data, open forum testimony, internet-based comments, letters, and editorials) relevant to each topic was considered in the development of these updated guidelines. Gastric emptying of preoperative carbohydrate in elderly assessed using gastric ultrasonography: A randomized controlled study. Aspiration of gastric contents is associated with increased perioperative morbidity and mortality [ 1-3 ], with highest risk associated with high volume, acidic, or particulate aspiration. Please be advised that if you have any questions regarding NPO status, call or email our office prior to the day of surgery for an answer. In addition, both the consultants and ASA members strongly agree that verification of their compliance with the fasting requirements should be assessed at the time of the procedure. Prospective nonrandomized comparative studies (e.g., quasi-experimental, cohort). These recommendations may be adopted, modified, or rejected according to clinical needs and constraints and are not intended to replace local institutional policies. Category A evidence represents results obtained from randomized controlled trials (RCTs) and Category B evidence represents observational results obtained from nonrandomized study designs or RCTs without pertinent comparison groups. In adults, evidence comparing fasting with chewing gum was inconsistent with respect to patient-rated hunger92 or thirst92,93 (very low strength of evidence). 18 to 20, https://links.lww.com/ALN/C935, and supplemental tables 5 and 6, https://links.lww.com/ALN/C934). Lansoprazole reduces preoperative gastric fluid acidity and volume in children. Effect of metoclopramide on gastric fluid volumes in diabetic patients who have fasted before elective surgery. Assessment of gastric emptying of maltodextrin, coffee with milk and orange juice during labour at term using point of care ultrasound: A non-inferiority randomised clinical trial. Supplemental Digital Content is available for this article. A complete bibliography used to develop these updated guidelines, arranged alphabetically by author, is available as Supplemental Digital Content 1, http://links.lww.com/ALN/B340. Excluded studies with reasoning are shown in the Supplemental Digital Content (https://links.lww.com/ALN/C933). Copyright 2023, the American Society of Anesthesiologists. Supplemental tables 13 and 14 (https://links.lww.com/ALN/C934) detail the strength-of-evidence ratings. These practice guidelines are a modular update of the 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. The guidance focuses on topics not addressed in the previous guideline: ingestion of carbohydrate-containing clear liquids with or without protein, chewing gum, and pediatric fasting duration. Rectal and oral cimetidine for prophylaxis of aspiration pneumonitis in paediatric anaesthesia. Comparative trial of the effect of ranitidine and cimetidine on gastric secretion in fasting patients at induction of anaesthesia. Home glucometer readings may help guide the patients choice of a carbohydrate or a noncaloric clear liquid. Girish P. Joshi, M.B.B.S., M.D., Dallas, Texas; Basem B. Abdelmalak, M.D., Cleveland, Ohio; Wade A. Weigel, M.D., Seattle, Washington; Monica W. Harbell, M.D., Phoenix, Arizona; Catherine I. Kuo, M.D., Downers Grove, Illinois; Sulpicio G. Soriano, M.D., Boston, Massachusetts; Paul A. Stricker, M.D., Philadelphia, Pennsylvania; Tommie Tipton, B.S.N., R.N., C.N.O.R., Dallas, Texas; Mark D. Grant, M.D., Ph.D., Schaumburg, Illinois; Anne M. Marbella, M.S., Schaumburg, Illinois; Madhulika Agarkar, M.P.H., Schaumburg, Illinois; Jaime Friel Blanck, M.L.I.S., M.P.A., Baltimore, Maryland; Karen B. Domino, M.D., M.P.H., Seattle, Washington. Search terms consisted of the interventions indicated above guided by the appropriate inclusion/exclusion criteria as stated in the Focus section of these updated guidelines. Meaningful differences were not apparent for either residual gastric volume34,38,41,44,46,4851,62,6871 (supplemental fig. 15 to 16, https://links.lww.com/ALN/C935) and thirst2342 compared with fasting patients (moderate strength of evidence). The consultants and ASA members both disagree that preoperative antacids should be routinely administered before elective procedures requiring general anesthesia, regional anesthesia, or procedural sedation and analgesia in patients with no apparent increased risk for pulmonary aspiration. Effects and safety of preoperative oral carbohydrates in radical distal gastrectomyA randomized clinical trial. Hypoglycaemia in children before operation: its incidence and prevention. Although the literature is insufficient to evaluate the influence of preoperatively adding milk or milk products to clear liquids (e.g., tea or coffee) on either pulmonary aspiration, gastric volume, pH, or gastric emptying, some studies with healthy volunteer subjects have reported equivocal findings for gastric volume and gastric emptying when these products are added to clear liquids.5254. Both simple and complex carbohydratecontaining clear liquids were slightly more advantageous compared with noncaloric clear liquids in patient satisfaction. Observational (e.g., correlational or descriptive statistics). Reaction score. All discrepancies were resolved. Differences were not detected in regurgitation43,49,55,66,68,69 (very low strength of evidence) or preoperative vomiting39,5052,62 (low strength of evidence). All protein-containing clear liquids also contained carbohydrates. Effects of preoperative oral carbohydrate supplementation on postoperative metabolic stress response of patients undergoing elective abdominal surgery. Guideline panels should seldom make good practice statements: Guidance from the GRADE working group. This article is featured in This Month in Anesthesiology, page A1. Airway management techniques that are intended to reduce the occurrence of pulmonary aspiration are not the focus of these guidelines. Perform a review of pertinent medical records, a physical examination, and patient survey or interview as part of the preoperative evaluation. Use of ultrasound for gastric volume evaluation after ingestion of different volumes of isotonic solution. The goal for preoperative fasting is to reduce the risk of aspiration of gastric contents. Menthol chewing gum on preoperative thirst management: Randomized clinical trial. Preoperative fasting guidelines in pediatric anesthesia: Are we ready for a change? The American Society of Anesthesiologists (ASA) recommends patients to fast from fatty food or meats eight (8) hours prior to surgery, non-human milk or light meal for six (6) hours prior, breast milk for four (4) hours prior, and clear liquids including water, pulp-free juice, and tea or coffee without milk for two (2) hours prior to the Only 2 of the trials randomized participants into 1- and 2-h fasting protocols; the remaining studies were not designed to compare 1- and 2-h fasting; however, they included results from pediatric patients fasted less than 2h. Most children were ASA Physical Status I or II, although one trial enrolling patients with cyanotic congenital heart disease were more likely of higher ASA Physical Status (ASA Physical Status not reported). Reduction of complications associated with pulmonary aspiration. asa npo guidelines 2020 chewing tobaccohershey high school homecoming 2019. Level 2: The literature contains multiple RCTs, but the number of RCTs is not sufficient to conduct a viable meta-analysis for the purpose of these updated guidelines.