Topic summary

Follow-up: Dead volume across syringe and needle combinations

Devices › Syringes & needles syringe units worked example subcutaneous injection dead volume needle gauge & length Solved

This is a generated summary. It shows the 9 most-liked posts from a topic of 99, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

journalclub_wrenTL3Regular Solution4 Jul 2024 · edited#6

steady_state, post #4: post #3 is right about the mechanism and I think understates the practical bit. Needle length: typical lengths for subcutaneous injection are 4-6 mm (short), 8 mm (standard), or 10-12 mm (longer). Longer needles are needed for deeper tissue or if you have abdominal adiposity. Go to post

Picking up post #3: that is the part I would want checked first.

Syringe barrel size: common sizes are 0.3 mL, 0.5 mL, and 1.0 mL. Smaller barrels are more legible for small doses. Larger barrels hold larger volumes. Choose based on your dose.

26 likes in reply to #4 2.1y

fr.translation_moTL2Translator · FR7 Aug 2024#18

On post #14 — agreed on the reasoning, with one qualification.

Needle length: typical lengths for subcutaneous injection are 4-6 mm (short), 8 mm (standard), or 10-12 mm (longer). Longer needles are needed for deeper tissue or if you have abdominal adiposity.

30 likes 2y

e.roosTL2 Moderator21 Aug 2024#24

n.ekstrom, post #2: Reading units correctly: look at the marking from the side, not from above or below. The bottom of the plunger tip is the reading. Parallax error (wrong angle) is a source of dosing error. Go to post

Insulin syringe graduations: U-100 syringes are marked in units where 100 units = 1 mL. Always confirm your syringe is U-100. Confusion between insulin units and milligrams is the most common syringe error.

25 likes in reply to #2 23mo

ppm_errorTL3Analytical chemist15 Sep 2024#35

b.wikstrom, post #26: Picking up post #23: that is the part I would want checked first. For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use. Go to post

Needle gauge: smaller numbers (30G) are finer and less painful. Larger numbers (25G) are courser. For subcutaneous injection, 27-30G is typical. Finer needles take longer to draw up but hurt less.

25 likes in reply to #26 22mo

o.vogelTL2 Moderator28 Sep 2024#41

s.antonsen, post #38: Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive. Go to post

Sharps disposal: needles and syringes should be disposed in a sharps container (a rigid, puncture-resistant container). Do not put them in regular trash. Many pharmacies accept filled sharps containers.

27 likes in reply to #38 22mo

k.kuuselaTL2 Moderator26 Oct 2024#55

Reading units correctly: look at the marking from the side, not from above or below. The bottom of the plunger tip is the reading. Parallax error (wrong angle) is a source of dosing error.

29 likes in reply to #38 21mo

e.steinerTL2 Moderator30 Nov 2024#74

I read post #72 twice before replying, because I had assumed the opposite.

Needle gauge: smaller numbers (30G) are finer and less painful. Larger numbers (25G) are courser. For subcutaneous injection, 27-30G is typical. Finer needles take longer to draw up but hurt less.

27 likes 20mo

da.bakkerTL2 Moderator23 Dec 2024#87

Coming back to post #85, because the follow-up matters more than the original answer.

28 likes 19mo

system_suitabilityTL3Analytical chemist1 Jan 2025#92

I read post #90 twice before replying, because I had assumed the opposite.

Needle gauge: smaller numbers (30G) are finer and less painful. Larger numbers (25G) are courser. For subcutaneous injection, 27-30G is typical. Finer needles take longer to draw up but hurt less.

31 likes 19mo

Read the full topic (99 posts)

This topic was referenced in

0.3 mL versus 0.5 mL versus 1 mL barrels: resolution mattersDevices › Syringes & needles · 114 replies
Reading U-100 graduations, with a conversion table — one year onDevices › Syringes & needles · 7 replies
Second pass at: Gauge and length selection for subcutaneous injectionDevices › Syringes & needles · 58 replies

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