Newly Published
Perioperative Medicine  |   May 2020
Preoperative Fluid Fasting Times and Postinduction Low Blood Pressure in Children: A Retrospective Analysis
Author Notes
  • From the Departments of Anesthesiology and Critical Care Medicine (A.F.S., L.W., O.N., J.A.G., J.M.T., J.O.W., W.T.M., F.-C.T., A.J.M., P.A.S.) and Biomedical and Health Informatics (A.F.S., L.W., J.A.G., J.M.T., J.O.W., F.-C.T., A.J.M.), Children’s Hospital of Philadelphia,Philadelphia, Pennsylvania; and the Department of Anesthesiology and Critical Care, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (A.F.S., J.A.G., J.M.T., J.O.W., W.T.M., F.-C.T., A.J.M., P.A.S.).
  • Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).
    Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).×
  • Part of the work presented in this article has been presented at the 10th European Congress in Pediatric Anesthesia in Brussels, Belgium, September 7, 2018, and the Society for Pediatric Anesthesia 2019 Annual Meeting in Houston, Texas, March 16, 2019.
    Part of the work presented in this article has been presented at the 10th European Congress in Pediatric Anesthesia in Brussels, Belgium, September 7, 2018, and the Society for Pediatric Anesthesia 2019 Annual Meeting in Houston, Texas, March 16, 2019.×
  • Submitted for publication April 13, 2019. Accepted for publication April 7, 2020.
    Submitted for publication April 13, 2019. Accepted for publication April 7, 2020.×
  • Correspondence: Address correspondence to Dr. Simpao: 3401 Civic Center Boulevard, Philadelphia, Pennsylvania 19104. simpaoa@email.chop.edu. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Article Information
Perioperative Medicine / Cardiovascular Anesthesia / Pediatric Anesthesia
Perioperative Medicine   |   May 2020
Preoperative Fluid Fasting Times and Postinduction Low Blood Pressure in Children: A Retrospective Analysis
Anesthesiology Newly Published on May 15, 2020. doi:https://doi.org/10.1097/ALN.0000000000003343
Anesthesiology Newly Published on May 15, 2020. doi:https://doi.org/10.1097/ALN.0000000000003343
Abstract

Background: Children are required to fast before elective general anesthesia. This study hypothesized that prolonged fasting causes volume depletion that manifests as low blood pressure. This study aimed to assess the association between fluid fasting duration and postinduction low blood pressure.

Methods: A retrospective cohort study was performed of 15,543 anesthetized children without preinduction venous access who underwent elective surgery from 2016 to 2017 at Children’s Hospital of Philadelphia. Low blood pressure was defined as systolic blood pressure lower than 2 standard deviations below the mean (approximately the 2.5th percentile) for sex- and age-specific reference values. Two epochs were assessed: epoch 1 was from induction to completion of anesthesia preparation, and epoch 2 was during surgical preparation.

Results: In epoch 1, the incidence of low systolic blood pressure was 5.2% (697 of 13,497), and no association was observed with the fluid fasting time groups: less than 4 h (4.6%, 141 of 3,081), 4 to 8 h (6.0%, 219 of 3,652), 8 to 12 h (4.9%, 124 of 2,526), and more than 12 h (5.0%, 213 of 4,238). In epoch 2, the incidence of low systolic blood pressure was 6.9% (889 of 12,917) and varied across the fasting groups: less than 4 h (5.6%, 162 of 2,918), 4 to 8 h (8.1%, 285 of 3,531), 8 to 12 h (5.9%, 143 of 2,423), and more than 12 h (7.4%, 299 of 4,045); after adjusting for confounders, fasting 4 to 8 h (adjusted odds ratio, 1.33; 95% CI, 1.07 to 1.64; P = 0.009) and greater than 12 h (adjusted odds ratio, 1.28; 95% CI, 1.04 to 1.57; P = 0.018) were associated with significantly higher odds of low systolic blood pressure compared with the group who fasted less than 4 h, whereas the increased odds of low systolic blood pressure associated with fasting 8 to 12 h (adjusted odds ratio, 1.11; 95% CI, 0.87 to 1.42; P = 0.391) was nonsignificant.

Conclusions: Longer durations of clear fluid fasting in anesthetized children were associated with increased risk of postinduction low blood pressure during surgical preparation, although this association appeared nonlinear.

Editor’s Perspective:

What We Already Know about This Topic:

  • Small studies of focused pediatric surgical patient populations demonstrate that prolonged fasting before surgery is associated with hypotension during anesthesia induction and surgical preparation

  • Consensus guidelines regarding the optimal fasting duration lack robust evidence across a broad range of ages and procedures

What This Article Tells Us That Is New:

  • Among 15,443 pediatric patients undergoing elective surgery with inhalational anesthetic induction, approximately 5% experience hypotension during anesthesia induction and 7% during surgical preparation

  • Compared with fasting less than 4 h, fasting between 4 and 8 h or more than 12 h is associated with a 30% increase in the risk of hypotension during surgical preparation

  • Hypotension during anesthesia induction is not associated with any specific duration of fasting