Understanding the IDDSI Framework
The International Dysphagia Diet Standardisation Initiative (IDDSI) provides a globally recognized framework with standardized terminology to describe food and drink consistencies. This consistency ensures that patients, caregivers, and clinicians all use the same language, significantly reducing the risk of error in preparing thickened liquids. The liquid scale ranges from Level 0 (Thin) to Level 4 (Extremely Thick), with specific criteria for each level. This framework empowers individuals with dysphagia and their caregivers to prepare and verify liquids consistently, which is critical for safe swallowing. Thickened liquids move more slowly through the mouth and throat, giving the individual more time to coordinate the swallow and protecting the airway from accidental aspiration.
Choosing and Using Commercial Thickeners
Commercial thickening products are designed for convenience and consistency, and are available in powder or gel formats. These products often come with specific instructions for achieving different IDDSI levels with various liquids.
Types of commercial thickeners
Commercial thickeners generally fall into two main categories: starch-based and gum-based.
- Starch-based thickeners: These typically use modified maize starch. They are known to have a less stable consistency, as they can continue to thicken over time and with changes in temperature. Some people may notice a grainy texture and starch-like taste.
- Gum-based thickeners: Often made from xanthan gum, these tend to provide a more consistent and stable thickness over time and across different temperatures. They are generally tasteless and clear, avoiding the opaque or cloudy appearance of starch-based thickeners.
How to mix thickeners
Proper mixing is essential to avoid lumps and achieve the correct consistency. Always refer to the specific manufacturer's instructions, but the general steps are:
- Measure: Use the scoop provided with the thickener or a precise measure for the specified amount of liquid. Accurately measuring is key to achieving the correct IDDSI level.
- Pour and Stir: Pour the measured liquid into a cup. Add the correct amount of thickener powder or gel. Stir briskly with a whisk or fork for the recommended amount of time (e.g., 30 seconds) to ensure it is fully mixed.
- Wait: Allow the liquid to stand for the time specified on the thickener package. This can range from a couple of minutes for gum-based thickeners to longer for starch-based ones, which may continue to thicken.
- Test: Always perform an IDDSI test before serving to confirm the liquid is at the prescribed level.
Special considerations for liquids
- High-fat liquids: Beverages like milk or cream-based soups can take longer to thicken, so additional waiting time may be needed.
- Acidic liquids: Juices with high acidity can sometimes affect the thickening process, especially with starch-based products.
- Carbonated drinks: Stir out the carbonation first to prevent fizzing, which can interfere with the thickening process.
Testing the Thickened Liquid for IDDSI Compliance
To ensure safety, you must confirm that the liquid reaches the correct IDDSI level. The IDDSI Flow Test is the gold standard for liquid levels 0-3.
- Obtain a 10ml syringe: Ensure it is a 'slip-tip' syringe, without a plunger.
- Cover the tip: Place a finger over the tip to prevent liquid from flowing out.
- Fill the syringe: Fill with 10ml of the prepared thickened liquid.
- Time the flow: Simultaneously release your finger from the tip and start a timer for 10 seconds.
- Check the residual volume: After 10 seconds, cover the tip again and measure the amount of liquid remaining in the syringe.
IDDSI Level Flow Test Results
| IDDSI Level | Name (Adults) | Flow Test Result (Residual in 10ml Syringe) | Other Characteristics |
|---|---|---|---|
| Level 0 | Thin | 0-1 ml | Flows like water, can be drunk from a cup or straw. |
| Level 1 | Slightly Thick | 1-4 ml | A little thicker than water, flows through a straw easily. |
| Level 2 | Mildly Thick | 4-8 ml | Some effort needed for a straw, can be sipped from a cup. |
| Level 3 | Moderately Thick | > 8 ml (but less than 10ml) | Pours slowly, can be drunk from a cup or taken with a spoon. |
| Level 4 | Extremely Thick | 10 ml (or no movement) | Spoon-thick consistency, no flow, eaten with a spoon. |
Preventing Common Thickening Problems
Lumps and inconsistency
- Always add the thickener to the liquid, not the other way around.
- Mix briskly and thoroughly with a whisk to break up any powder clumps immediately.
- Allow for the full recommended stand time to reach the final, stable consistency.
Avoiding dehydration
Thickened liquids can reduce the sensation of thirst and cause individuals to drink less.
- Offer smaller, more frequent portions of thickened liquid throughout the day.
- Ensure that pre-thickened items like gelatine and ice cream, which melt back to a thin liquid, are avoided.
- Include moist, IDDSI-compliant pureed foods like sauces, soups, and fruits to boost fluid intake.
Medication interactions
Certain thickening agents, particularly xanthan gum, can bind with positively charged medications and affect their bioavailability. Consult with a pharmacist to understand potential interactions.
- Administer medication separately with a small amount of liquid, or consider alternative formulations if possible.
- Avoid mixing starch-based thickeners with macrogol laxatives, as this can thin the mixture and pose an aspiration risk.
Conclusion
Thickening liquids according to IDDSI guidelines is a proven method for managing dysphagia and improving swallowing safety. By understanding the different IDDSI levels, selecting the appropriate commercial thickener, and performing the simple IDDSI Flow Test, caregivers and patients can ensure consistent and safe liquid intake. Consistent practice, coupled with careful monitoring for dehydration and medication effects, will provide the best outcome for individuals with swallowing difficulties. For further information and video demonstrations of the IDDSI tests, visit the official IDDSI website [www.iddsi.org].
Homemade Thickening Methods
For some situations or with a clinician's approval, household ingredients can be used for thickening liquids or pureed foods. However, these methods are less precise and often less stable than commercial products, requiring more frequent checks.
Natural thickening options
- Cornstarch or Flour: Mix with a small amount of cold water to form a 'slurry' before adding to hot puréed soups or sauces. Remember that cooking and cooling will continue to affect the final thickness.
- Infant Rice Cereal: Add to cold drinks like milk or shakes for thickening.
- Instant Potato Flakes: Works well for thickening boiling puréed soups and sauces.
- Pureed Fruits/Vegetables: Adds natural thickness and flavour to smoothies and other drinks.
Caveats of homemade thickeners
- Inconsistent Results: The final thickness can vary widely due to temperature, food acidity, and cook time.
- Stand Time: The thickness can change over time, requiring re-testing before each serving.
- Professional Guidance: These methods should only be used under the guidance of a healthcare professional to ensure the target IDDSI level is met consistently.
