From the Guidelines
Clear fluids in the Enhanced Recovery After Surgery (ERAS) protocol are defined as transparent liquids that allow light to pass through them and do not contain solid particles or pulp, and can be consumed up to 2 hours before anesthesia induction, as recommended by the most recent guidelines 1. These include water, clear fruit juices without pulp (such as apple or white grape juice), clear sports drinks, clear tea or coffee without milk or cream, clear broths, clear carbonated beverages, and plain gelatin. The evidence suggests that clear fluids empty from the stomach rapidly (within 1-2 hours) and do not increase aspiration risk, which supports the ERAS protocol's approach of allowing patients to consume clear fluids up until 2 hours before anesthesia induction, rather than requiring traditional overnight fasting 1. Some key points to consider when defining clear fluids in the ERAS protocol include:
- The carbohydrate content in some clear fluids (like apple juice or carbohydrate-rich clear drinks) can help reduce insulin resistance, decrease protein breakdown, and minimize patient discomfort from prolonged fasting 1.
- Patients should be specifically instructed that milk-containing beverages, smoothies, juices with pulp, and alcoholic beverages are not considered clear fluids and should be avoided during the pre-operative period 1.
- Relative contraindications to clear fluids include gastro-oesophageal reflux, renal failure, some enteropathies, oesophageal strictures, achalasia, diabetes mellitus with gastroparesis, and/or surgical contraindications 1. It is essential to weigh the theoretical risk against the benefits on an individual basis when making decisions about clear fluid consumption in the pre-operative period 1.
From the Research
Definition of Clear Fluids in ERAS Protocol
The definition of clear fluids in the Enhanced Recovery After Surgery (ERAS) protocol is not explicitly stated in the provided studies. However, based on the context, clear fluids can be inferred to include:
- Carbohydrate-containing clear liquids, such as those recommended for preoperative hydration 2, 3
- Oral electrolyte solutions, such as glucose-containing reduced osmolarity World Health Organization ORS 4
- Other clear liquids, such as water or broth, although these may not be explicitly recommended for ERAS protocols
Key Characteristics of Clear Fluids
Clear fluids in the ERAS protocol are likely to have the following characteristics:
- Transparent or clear in appearance
- Low in solids and residue
- Able to be consumed orally
- May contain carbohydrates, electrolytes, or other nutrients to support hydration and recovery
Examples of Clear Fluids
Examples of clear fluids that may be included in the ERAS protocol are:
- Carbohydrate-containing clear liquids, such as sports drinks or oral rehydration solutions
- Broth or clear soups
- Water or other low-calorie, low-electrolyte beverages
- Electrolyte-rich beverages, such as coconut water or sports drinks with added electrolytes 4
Exclusions
The following fluids are not considered clear fluids in the ERAS protocol:
- Thick or opaque liquids, such as milkshakes or smoothies
- High-fiber or high-residue liquids, such as those containing pulp or sediment
- Liquids with high sugar or calorie content, such as soda or juice 4