Feasibility and Utility of Routine Point-of-Care Gastric Ultrasonography in Patients Undergoing Upper Gastrointestinal Endoscopy Procedures: A Prospective Cohort Study

OBJECTIVES

Previous studies have indicated that point-of-care ultrasonography (POCUS) of the gastric antrum can predict the adequacy of fasting before surgery and anesthesia. The aim of this study was to evaluate the utility of gastric POCUS in patients undergoing upper gastrointestinal (GI) endoscopy procedures.

METHODS

We performed a single-center cohort study in patients undergoing upper GI endoscopy. Consenting patient's gastric antrum was scanned before anesthetic care for endoscopy to determine the cross-sectional area (CSA) and qualitatively determine safe and unsafe contents. Further, an estimate of residual gastric volume was determined using the formula and the nomogram methods. Subsequently, gastric secretions aspirated during endoscopy were quantified and further correlated with nomogram and formula-based assessments. No patient required a change in the primary anesthetic plan except for using rapid sequence induction in those with unsafe contents on POCUS scans.

RESULTS

Qualitative ultrasound measurements consistently determined safe and unsafe gastric residual contents in 83 patients enrolled in the study. Unsafe contents were determined by qualitative scans in 4 out of 83 cases (5%) despite adequate fasting status. Quantitatively, only a moderate correlation was demonstrated between measured gastric volumes and nomogram (r = .40, 95% CI: 0.20, 0.57; P = .0002) or formula-based (r = .38, 95% CI: 0.17, 0.55; P = .0004) determinations of residual gastric volumes.

CONCLUSION

In daily clinical practice, qualitative POCUS determination of residual gastric content is a feasible and useful technique to identify patients at risk of aspiration before upper GI endoscopy procedures.

A Comparative Study of Fasting Gastric Volume in Diabetic and Non-diabetic Patients Undergoing Elective Surgeries Using Ultrasonography: A Prospective Observational Study

BACKGROUND

Gastric ultrasound can be used to evaluate the residual gastric volume (GV) and contents before anesthetizing a patient. Autonomic gastropathy in patients with diabetes increases the risk of pulmonary aspiration of gastric contents. Therefore, the present study was conducted to assess the fasting GV among diabetics and healthy individuals using point-of-care (POC) ultrasonography.

MATERIALS AND METHODS

This prospective observational study was conducted in a tertiary care hospital between January 2021 and February 2022. A total of 122 patients included in the study were divided into two groups: group D (n = 61) patients had a history of diabetes mellitus and group C (n = 61) patients were non-diabetics (control). Gastric ultrasound was performed in supine and right lateral decubitus (RLD) positions. The following parameters were measured: duration of fasting, craniocaudal (CC) diameter, anteroposterior (AP) diameter, cross-sectional area (CSA), and GV using CC and AP diameters.

RESULTS

The mean age of the participants was found to be 46.60 ± 13.77 years with 51.6% female patients and 48.4% male patients. Among the patients, there was a significantly higher mean level of CC diameter, AP diameter, and CSA in the supine position in diabetics compared to controls (p < 0.05). Similarly, there was a significantly higher mean level of CC diameter, AP diameter, and CSA in the RLD position in diabetics compared to healthy individuals (p < 0.05). The GV was significantly higher in diabetics (9.96 ± 14.520) compared to healthy individuals (-8.991 ± 20.95; p < 0.05).

CONCLUSION

Fasting GV assessed using POC ultrasonography in diabetic individuals was higher when compared to non-diabetics after similar periods of fasting.

Gastric emptying of preoperative carbohydrate in elderly assessed using gastric ultrasonography: A randomized controlled study

BACKGROUND

Preoperative carbohydrate loading enhances postoperative recovery and reduces patient discomfort. However, gastric emptying of liquids can be delayed in elderly populations. Therefore, this study aimed to evaluate the gastric emptying of 400 mL of a carbohydrate drink ingested 2 hours before surgery in elderly patients.

METHODS

In this prospective, randomized controlled study, patients aged >65 years were allocated to either fast from midnight (nil per os [NPO] group, n = 29) or drink 400 mL of a carbohydrate drink 2 hours before surgery (carbohydrate group, n = 29). The gastric antrum was assessed using ultrasonography in the supine position, followed by the right lateral decubitus (RLD) position. The gastric antrum was graded as grade 0 (fluid not seen in both positions), grade 1 (fluid only seen in the RLD position), and grade 2 (fluid seen in both positions). The gastric antral cross-sectional area (CSA) and aspirated residual gastric volume were measured.

RESULTS

In 58 patients, the incidence of grade 2 stomach was 13.8% in NPO group and 17.2% in carbohydrate group (P = .790). The gastric antral CSA in the supine position was larger in carbohydrate group than in NPO group (4.42 [3.72-5.18] cm2 vs 5.31 [4.35-6.92] cm2, P = .018). The gastric antral CSA in the RLD position was not different in NPO and carbohydrate groups (P = .120). There was no difference in gastric volume (2 [0-7.5] vs 3 [0-13.4], P = .331) in NPO group versus carbohydrate group.

CONCLUSION

The incidence of grade 2 stomach was not different between NPO group and carbohydrate group in elderly patients.

Type 2 Diabetes Mellitus: Relationships Between Preoperative Physiologic Stress, Gastric Content Volume and Quality, and Risk of Pulmonary Aspiration

Pulmonary aspiration is a potentially fatal anesthetic complication occurring when gastric contents enter the respiratory system. Fasting guidelines aim to decrease the risk of pulmonary aspiration by recommending a timeframe in which patients abstain from food and drink before surgery. Fasting guidelines recommended for healthy individuals fail to account for patients with type 2 diabetes mellitus (T2DM). Gastroparesis, a common condition associated with T2DM, is exacerbated during stress such as an impending surgery. This study sought to determine whether a relationship exists between stress levels and gastric contents in fasting patients with T2DM presenting for an elective surgical or diagnostic procedure. The quality and quantity of gastric contents and preoperative stress were evaluated using gastric ultrasonography and salivary α-amylase levels. No relationship existed between preoperative stress and gastric contents; however, glycated hemoglobin levels of 7% or greater were associated with increased gastric fluid, which was the most significant finding in this study. In addition, there was a significant difference between the mean gastric volume in healthy individuals and patients with T2DM. Performance of gastric ultrasonography preoperatively provides objective data that could influence the anesthetic plan and decrease the risk of pulmonary aspiration in patients with T2DM.