"My blood vessels are so thin that it's hard to get an IV needle in."
- "My blood vessels are so thin that it's hard to get an IV needle in."
"my blood vessels" 「私の血管が」"my veins" 「私の静脈」も言えます。
"so thin" 「細くて」"too thin" 「細すぎ」も使えます。
"it's hard to get ~ in" 「〜が入りにくい」
"an IV needle" 「点滴の針」
My veins are not very big, so it's hard for the nurse to get the needle in my arm.
I don't have very good veins which makes it hard for the nurse to administer an intravenous drip.
血管が細いことは one's veins are not very big や don't have very good veins と言うと良いですよ。
ーMy veins are not very big, so it's hard for the nurse to get the needle in my arm.
「血管が細くて、看護師が私の腕に（点滴や注射の）針を入れづらい」
ーI don't have very good veins which makes it hard for the nurse to administer an intravenous drip.
「良い血管じゃないので、看護師が私に点滴をするのは大変だ」
点滴は intravenous drip を省略して IV と言うことが多いです。
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