Gastric Ultrasound in Pediatric Trauma Patients

Study Overview
=================
Brief Summary
-----------------
Gastric ultrasound has become increasingly utilized to examine volume and quality of gastric contents in the preoperative setting to guide anesthetic management and relay risk of aspiration in both adult and pediatric medicine. Gastric fluid volumes in trauma patients are thought to be elevated due to delayed gastric emptying in the setting of an over-attenuated sympathetic response to physical pain and stress, opioid analgesia, and other associated injuries (traumatic brain). However, there is a paucity of literature examining gastric fluid volumes (GFV), measured by gastric ultrasound, in the pediatric trauma population. The purpose of the study is to assess whether preoperative gastric ultrasound is an accurate method to identify pediatric trauma patients who have elevated GFV (>0.8mL/kg) and high-risk gastric contents (solids, complex liquids, in addition to large volumes).

Detailed Description
-----------------
There is longstanding evidence that GFV are elevated in trauma patients for several physiologic reasons. This has been corroborated in both adult and pediatric studies, suggesting that trauma patients may be at higher risk for gastric aspiration compared to healthy controls, and that anesthetic management should reflect this elevated risk. This often implies tracheal intubation with or without a rapid sequence induction. However, performing rapid sequence induction to decrease aspiration risk increases the risk of desaturation, hypoxia, bradycardia, and hemodynamic instability, especially in small children who have reduced functional residual capacity and who are difficult to adequately preoxygenate. This has presented a question-mark for anesthesia providers caring for children with traumatic injuries, and variations in practice. Bricker and authors examined gastric fluid volumes by aspiration of gastric contents in 1989 in pediatric trauma patients, and found that nearly 50% had elevated gastric contents and were at risk for potential aspiration, though no aspiration events were captured. Likewise, Schurizek and authors looked a cohort of pediatric patients presenting for emergency surgery, which included trauma, and found the nearly 38% of children presenting to the OR who had adequately fasted had elevated gastric contents. A recent study using gastric ultrasound in children with proximal limb fractures found a similar rate of elevated gastric contents with 37% of children meeting criteria, and 24% of those showing evidence of solids/complex gastric fluid. Again, no aspiration events were captured. Thus, little is known to inform anesthesiologists about which risk factors contribute to high gastric volumes in pediatric trauma patients or how long these children may be considered at additional risk for aspiration. Aspiration is an extremely rare event, typically estimated between 1-5/10,000 anesthetics or 0.01%, and the sample size needed to power a study to capture reducing the risk of aspiration is not feasible. Thus, the investigators hope to characterize gastric contents/GFV using ultrasound in pediatric trauma patients presenting with a wide variety of traumatic injury and at varying times from injury (urgent/emergent surgery versus semi-urgent surgery), to identify potential risk factors and guide anesthetic management in this vulnerable population.

Official Title
-----------------
Evaluation of Gastric Contents by Ultrasound in Pediatric Trauma Patients Undergoing General Anesthesia

Conditions
-----------------
Trauma; Complications, Aspiration

Intervention / Treatment
-----------------
* Diagnostic Test: Gastric Ultrasound


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Pediatric patients ages 0-17 years-old Patients suffering from a traumatic injury requiring urgent or emergent surgery. Inpatient or Same-Day Surgery Exclusion Criteria: Children with altered or abnormal gastric physiology, ie, history of Nissen Fundoplication, history of short-gut syndrome, history of bariatric surgery/gastric sleeve, history of gastroparesis or functional dysmotility, etc.

Ages Eligible for Study
-----------------
Minimum Age: 0 Years
Maximum Age: 17 Years

Sexes Eligible for Study
-----------------
All

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pediatric Trauma Patients<br>Pediatric patients (<18 years old) who have suffered a traumatic event requiring surgical fixation within 48 hours prior to time to arrival in the operating room. | Diagnostic Test: Gastric Ultrasound<br>* The investigators will compare gastric fluid volume as determined by ultrasound pre-induction vs. gastric volume aspirated via an orogastric tube post-intubation. The results will be stratified into low risk, moderate risk and high risk for aspiration based on ultrasound exam by an investigator off-line.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gastric fluid volume (GFV) | GFV will be estimated via obtained gastric antral cross-sectional area (CSA), measured by ultrasound, and calculated using the formula: GSV= 0.0093 * CSA [mm2] - 0.96. This calculated GFV will be compared to aspirated gastric volumes. | GFV will be measured immediately prior to induction of general anesthesia within the operating room. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Airway management patterns | We will also collect data on airway management patterns in pediatric trauma patients (rapid-sequence induction, laryngeal mask airway, etc). | This data will be collected up to 1 year. | 
| Aspiration | Number of patients with aspiration intraoperatively. | This data will be collected up to 1 year. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
pediatric, trauma, gastric, ultrasound