Introduction - Helpful Tips
- Use a 10 french or larger feeding tube.
- In addition to NPO, instruct parents to discourage their child from very active play.
- Restrain the child very well. Wrap well in a sheet and then in a "papoose board."
- Encourage the parents to leave the room. The whole process takes less than 5 minutes.
- Get everything ready before starting (the syringe needs to fit the NG tube).
- Before placing the NG tube, measure the estimated length carefully and mark your goal length with a pen rather than a piece of tape.
- As you insert the tube, stay away from the nasal septum and aim the tube straight down toward the bed (not up toward the nasal bridge).
- If the child does not swallow as the tube passes into the throat, give a short puff into the child's face. This frequently elicits a swallow and allows the tube to pass without coiling in the mouth.
- Before putting any water down, check your stomach placement with a stethoscope.
- If you don't get mucus: Try advancing and withdrawing the tube several inches; try turning the child on the stomach, side, sitting up, etc.
- Work hard to get a good specimen the first day - it is the best yield.
- Three consecutive morning gastric aspirates have the best yield. Only one may be necessary for a child with a good presumed source case. Start the TB drugs after the second gastric aspirate (if the child is clinically stable).
- Use each day of the specimen collection for history/physical and TEACHING, TEACHING, TEACHING:
- What TB is and how important it is to do aggressive contact investigation.
- What the medications are; how to give the medications; what the side effects are.
- The important role of the health department.
- Remind parents that the yield of the gastric aspirates is only about 40% (even for known active TB) - so the test is only helpful if it is positive.
- A negative test does not rule out TB!
- To prepare the bicarbonate solution for neutralization, dissolve 2 . 5 grams NaHCO3 in 100 cc deionized water. Filter the solution through a 45μm filter. Add approximately 1.5 cc to each specimen and measure the pH. Adjust the pH of the specimen until it is neutralized. Compress to: 2.5 grams. Add approximately 1.5 ml of the bicarbonate solution to each clinical specimen. The lab should measure the pH of the specimen and adjust the pH until neutral.
- For infants who feed frequently and do not sleep all night, collect several specimens in a single day and put them in the same container (after your lab confirms a neutral pH). Collect them after a long nap and before feeding. Babies have the very highest yield.