Preoperative Fasting in Children

Assessing Residual Gastric Fluid Volume after Administering Diluted Oral Contrast until One Hour Prior to Anesthesia in Children: An Observational Cohort Study

Background: Gastric fluid volume has been used as a surrogate marker for pulmonary aspiration risk in studies evaluating fasting protocol safety. This study measured residual gastric fluid volume in children using a protocol in which diluted oral contrast medium was administered up until one hour before anesthesia. Methods: This was a single-center prospective observational cohort trial of 70 children for elective abdominal/pelvic computed tomography (CT). Imaging was performed after diluted enteral contrast medium administration, beginning two hours before and ending at least one hour before induction. For each patient, gastric fluid volume was calculated using an image region of interest. The primary outcome measure was gastric fluid volume measured using the computed tomography image. Results: The median time from the end of contrast administration to imaging was 1.5 h (range: 1.1 to 2.2 h). Residual gastric volume, measured using CT was <0.4 mL/Kg in 33%; ≥0.4 mL/Kg in 67%; and ≥1.5 mL/Kg in 44% of patients. Residual gastric volumes measured using CT and aspiration were moderately correlated (Spearman's correlation coefficient = 0.41, p = 0.0003). However, the median residual gastric volume measured using CT (1.17, IQR: 0.22 to 2.38 mL/Kg) was higher than that of aspiration (0.51, IQR: 0 to 1.58 mL/Kg, p = 0.0008 on differences in paired measures). Three cases of vomiting were reported. No evidence of pulmonary aspiration was identified. Conclusions: Children who receive large quantities of clear fluid up to one hour before anesthesia can have a significant gastric residual volume.

[Use of ultrasound for gastric volume evaluation after ingestion of different volumes of isotonic solution]

BACKGROUND AND OBJECTIVES

The current preoperative fasting guidelines allow fluid intake up to 2hours before surgery. The aim of this study was to evaluate the gastric volume of volunteers after an overnight fast and compare it with the gastric volume 2hours after ingestion of 200 and 500mL of isotonic solution, by means of ultrasound assessment.

METHOD

Eighty volunteers underwent gastric ultrasound at three times: after 8hours of fasting; 2hours after ingestion of 200mL isotonic saline, followed by the first scan; and on another day, 2hours after ingestion of 500mL of the same solution after an overnight fast. The evaluation was quantitative (antrum area and gastric volume, and the ratio of participants' gastric volume/weight) and qualitative (absence or presence of gastric contents on right lateral decubitus and supine positions. A p-value<0.05 was considered significant).

RESULTS

There was no difference in quantitative variables at measurement times (p>0.05). Five volunteers (6.25%) had a volume/weight over 1.5mL.kg^-1 at fasting and 2hours after ingestion of 200mL and 6 (7.5%) after 500mL. Qualitatively, the presence of gastric fluid occurred in more volunteers after fluid ingestion, especially 500mL (18.7%), although not statistically significant.

CONCLUSION

Ultrasound assessment of gastric volume showed no significant difference, both qualitative and quantitative, 2h after ingestion of 200mL or 500mL of isotonic solution compared to fasting, although gastric fluid content has been identified in more volunteers, especially after ingestion of 500mL isotonic solution.

Ketamine Sedation After Administration of Oral Contrast: A Retrospective Cohort Study

BACKGROUND

The American Academy of Pediatrics and American Society of Anesthesiologists have published consensus-based fasting guidelines intended to reduce the risk of pulmonary aspiration. The purpose of our study was to compare the rate of adverse events in patients sedated with ketamine within 2 hours of oral contrast intake to those who were nil per os (NPO).

METHODS

A retrospective cohort review of a database of children between July 2008 and May 2011. The rate of adverse events in children sedated with ketamine after intake of oral contrast for an abdominal computed tomography were compared with those sedated without taking oral contrast.

RESULTS

One hundred and four patients sedated for a computed tomography scan; 22 patients were sedated within 2 hours of taking oral contrast, and 82 were NPO. The 2 groups were comparable with regard to gender, race, and American Society of Anesthesiologists status. The mean (SD) time between the second dose of oral contrast and induction of sedation was 58 (24) minutes. Vomiting occurred in 4 of 22 patients in the oral contrast group (18%; 95% confidence interval 2%-34%) and 1 of 82 patients in the NPO group (1%; 95% confidence interval, 0%, 4%; P < .001). There was no difference in oxygen desaturation between the groups (P = .6).

CONCLUSIONS

Children who received oral contrast up to 58 minutes before ketamine sedation had a higher rate of vomiting than those who did not receive oral contrast. We did not identify cases of clinical aspiration, and the incidence of hypoxia between the 2 groups was not statistically significant.

Gastric emptying in children with gastroesophageal reflux and in healthy children

PURPOSE

The aim of this report is to examine whether children with gastroesophageal reflux (GER) have delayed gastric emptying compared to healthy children.

METHODS

All patients had GER verified by 24-hour pH monitoring. Gastric emptying of cow's milk was examined by radionuclide scintigraphy in 51 patients with GER and in 24 controls. Gastric emptying rate was expressed as exponential half time (T1/2).

RESULTS

Median age was 4.4 years [range 0.1-15.4] in patients and 6.1 years [range 2.5-10.0] in controls (p=.10). A wide range of gastric emptying rates was observed both in GER patients [range 16-121] and controls [range 29-94]. One GER patient (2%) had slower gastric emptying (T1/2=121 min) than the healthy child with the longest T1/2 (94 min). Mean T1/2 was 49 minutes (SD 20.1) and 46 minutes (SD 14.2) in GER patients and controls, respectively (p=.51).

CONCLUSIONS

Gastric emptying rate of milk was not significantly different between children with GER and healthy children. A wide range of gastric emptying rates was observed in both groups.

An update on pediatric endoscopy

Advances in endoscopy and anesthesia have enabled gastrointestinal endoscopy for children since 1960. Over the past decades, the number of endoscopies has increased rapidly. As specialized teams of pediatric gastroenterologists, pediatric intensive care physicians and pediatric endoscopy nurses are available in many medical centers, safe and effective procedures have been established. Therefore, diagnostic endoscopies in children are routine clinical procedures. The most frequently performed endoscopies are esophagogastroduodenoscopy (EGD), colonoscopy and endoscopic retrograde cholangiopancreaticography (ERCP). Therapeutic interventions include variceal bleeding ligation, foreign body retrieval and percutaneous endoscopic gastrostomy. New advances in pediatric endoscopy have led to more sensitive diagnostics of common pediatric gastrointestinal disorders, such as Crohn's disease, ulcerative colitis and celiac disease; likewise, new diseases, such as eosinophilic esophagitis, have been brought to light.Upcoming modalities, such as capsule endoscopy, double balloon enteroscopy and narrow band imaging, are being established and may contribute to diagnostics in pediatric gastroenterology in the future.

ABM Clinical Protocol #25: Recommendations for preprocedural fasting for the breastfed infant: "NPO" Guidelines

A central goal of The Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient. These guidelines are not intended to be all-inclusive, but to provide a basic framework for physician education regarding breastfeeding.

Perioperative fasting in adults and children: guidelines from the European Society of Anaesthesiology

This guideline aims to provide an overview of the present knowledge on aspects of perioperative fasting with assessment of the quality of the evidence. A systematic search was conducted in electronic databases to identify trials published between 1950 and late 2009 concerned with preoperative fasting, early resumption of oral intake and the effects of oral carbohydrate mixtures on gastric emptying and postoperative recovery. One study on preoperative fasting which had not been included in previous reviews and a further 13 studies published since the most recent review were identified. The searches also identified 20 potentially relevant studies of oral carbohydrates and 53 on early resumption of oral intake. Publications were classified in terms of their evidence level, scientific validity and clinical relevance. The Scottish Intercollegiate Guidelines Network scoring system for assessing level of evidence and grade of recommendations was used. The key recommendations are that adults and children should be encouraged to drink clear fluids up to 2 h before elective surgery (including caesarean section) and all but one member of the guidelines group consider that tea or coffee with milk added (up to about one fifth of the total volume) are still clear fluids. Solid food should be prohibited for 6 h before elective surgery in adults and children, although patients should not have their operation cancelled or delayed just because they are chewing gum, sucking a boiled sweet or smoking immediately prior to induction of anaesthesia. These recommendations also apply to patients with obesity, gastro-oesophageal reflux and diabetes and pregnant women not in labour. There is insufficient evidence to recommend the routine use of antacids, metoclopramide or H2-receptor antagonists before elective surgery in non-obstetric patients, but an H2-receptor antagonist should be given before elective caesarean section, with an intravenous H2-receptor antagonist given prior to emergency caesarean section, supplemented with 30 ml of 0.3 mol l(-1) sodium citrate if general anaesthesia is planned. Infants should be fed before elective surgery. Breast milk is safe up to 4 h and other milks up to 6 h. Thereafter, clear fluids should be given as in adults. The guidelines also consider the safety and possible benefits of preoperative carbohydrates and offer advice on the postoperative resumption of oral intake.

Oral contrast for abdominal computed tomography in children: the effects on gastric fluid volume

BACKGROUND

Oral enteric contrast medium (ECM) is frequently administered to achieve visualization of the gastrointestinal tract during abdominal evaluation with computed tomography (CT). Administering oral ECM less than 2 hours before sedation/anesthesia violates the nothing-by-mouth guidelines and in theory may increase the risk of aspiration pneumonia. In this study we measured the residual gastric fluid when using a protocol in which ECM is administered up to 1 hour before anesthesia/sedation. We hypothesized that patients receiving ECM 1 hour before anesthesia/sedation would have residual gastric fluid volume (GFV) >0.4 mL/kg.

METHODS

Anesthesia and radiology reports, CT images, and department incident reports were reviewed between January 2005 and June 2009 for all patients who required sedation/anesthesia for abdominal CT. For each patient, the volume of contrast or stomach fluid was calculated using a region of interest outlining the stomach portion containing high-attenuation fluid and low-attenuation of other gastric contents. Information obtained from anesthesia/sedation reports included demographic characteristics, presenting pathology, drugs used for anesthesia/sedation induction and maintenance, airway interventions, method for securing endotracheal tube, and complications related to ECM administration, including oxygen desaturation, vomiting, coughing, bronchospasm, laryngospasm, and aspiration.

RESULTS

We identified 365 patients (mean age = 32 months; range = 0.66 to 211.10 months) who received oral/IV contrast material before anesthesia/sedation for abdominal CT and 47 patients (mean age = 52 months; range = 0.63 to 215.84 months) who received only IV contrast material and followed the traditional fast. For those who received oral contrast, the mean contrast volume administered was 18.10 mL/kg (range = 1.5 to 82.76 mL/kg). The median GVF 1 hour after completing the oral contrast was significantly higher than that in patients who received only IV contrast (0.38 mL/kg vs. 0.15 mL/kg, P = 0.0049). GFV exceeded 0.4 mL/kg in 189 patients (178 of 365 [49%] in the oral contrast group vs. 11 of 47 [23%] in the IV contrast group) (χ(2) = 10.7874, P = 0.0010). Among those who received oral contrast, 207 patients had general anesthesia and 158 patients had deep sedation. Two cases of vomiting were reported in the general anesthesia group with no evidence of pulmonary aspiration identified.

CONCLUSION

For children receiving an abdominal CT, the residual GFV exceeded 0.4 mL/kg in 49% (178/365) of those who received oral ECM up to 1 hour before anesthesia/sedation in comparison with 23% (11/47) of those who received IV-only contrast.

The effect of preoperative nutritional face-to-face counseling about child's fasting on parental knowledge, preoperative need-for-information, and anxiety, in pediatric ambulatory tonsillectomy

OBJECTIVE

The objective of this study was to define how preoperative nutritional face-to-face counseling on child's fasting affects parental knowledge, preoperative need-for-information, and anxiety, in pediatric ambulatory tonsillectomy.

METHODS

The participants in the prospective, randomly allocated study were parents (intervention 62/control 62) with children (4-10 years) admitted for ambulatory tonsillectomy. Data were collected by the knowledge test designed for the study and with The Amsterdam preoperative anxiety and information scale (APAIS). The intervention group was invited to a preoperative visit to receive written and verbal face-to-face counseling. They were initiated into the child's active preoperative nutrition. The parents of the control group received current information without face-to-face counseling.

RESULTS

The parents followed the instructions. Their knowledge about the child's fast increased (p=0.003), and need-for-information and anxiety decreased (p<0.0001) significantly.

CONCLUSION

The preoperative face-to-face counseling with written information improves parental knowledge about the child's fasting and active preoperative nutrition, and relieves their need-for-information and anxiety.

PRACTICE IMPLICATIONS

The primary responsibility remains with the health care professionals when the active preoperative nutrition of the child and counseling on it are introduced into nursing practice.

Hyperphosphatemia after sodium phosphate laxatives in low risk patients: prospective study

AIM

To establish the frequency of hyperphosphatemia following the administration of sodium phosphate laxatives in low-risk patients.

METHODS

One hundred consecutive ASA I-II individuals aged 35-74 years, who were undergoing colonic cleansing with oral sodium phosphate (OSP) before colonoscopy were recruited for this prospective study.

EXCLUSION CRITERIA

congestive heart failure, chronic kidney disease, diabetes, liver cirrhosis, intestinal obstruction, decreased bowel motility, increased bowel permeability, and hyperparathyroidism. The day before colonoscopy, all the participants entered a 24-h period of diet that consisted of 4 L of clear fluids with sugar or honey and 90 mL (60 g) of OSP in two 45-mL doses, 5 h apart. Serum phosphate was measured before and after the administration of the laxative.

RESULTS

The main demographic data (mean +/- SD) were: age, 58.9 +/- 8.4 years; height, 163.8 +/- 8.6 cm; weight, 71 +/- 13 kg; body mass index, 26 +/- 4; women, 66%. Serum phosphate increased from 3.74 +/- 0.56 to 5.58 +/- 1.1 mg/dL, which surpassed the normal value (2.5-4.5 mg/dL) in 87% of the patients. The highest serum phosphate was 9.6 mg/dL. Urea and creatinine remained within normal limits. Post-treatment OSP serum phosphate concentration correlated inversely with glomerular filtration rate (P < 0.007, R(2) = 0.0755), total body water (P < 0.001, R(2) = 0.156) and weight (P < 0.013, R(2) = 0.0635).

CONCLUSION

In low-risk, well-hydrated patients, the standard dose of OSP-laxative-induced hyperphosphatemia is related to body weight.

[Airway protection in children with a full stomach]

Recent surveys have reevaluated the risk of aspiration of gastric content during anesthesia in pediatric patients. Emergency, bowel obstruction and inadequate depth of anesthesia are the main high-risk situations. Airway protection requires the placement of cuffed tracheal tube. Cuffed tubes were considered as non-useful in children aged less than 6 to 8 years. They are however more frequently employed even in infants. Internal diameter of cuffed tubes should be reduced compared to uncuffed tubes. It is recommended to monitor cuff pressure if nitrous oxide is used during anesthesia. Crash induction is described with special reference to pediatric specificities.