Indication
- 區分關節炎的種類(infective? crystalline?)
- 給予特定治療(關節腔注射)，ex. 葡萄糖水、玻尿酸、PRP
Contraindication
Absolute:
- Puncture site cellulitis or other infection
Relative:
- Coagulopathy(little harm)
- Bacteremia?
Procedure
- 先用echo掃描關節腔周圍四個象限+觸診，尋找關節液最多的地方，用棉棒末端定位(定位點再用兩個超音波平面確認入針處液體足夠)
- 無菌消毒*3，至少整個關節完成消毒
- 戴無菌手套、鋪設無菌洞巾
- 準備好抽吸針(18-22gauge)，針筒，確認定位後跟病人說明並且垂直入針
- 保持負壓進針直到抽到關節液，大約抽到20-40cc即可
- 用紗布將入針處蓋起來並加壓5-10分鐘
- 告知觀察是否有後續局部紅腫熱痛
(可局部麻醉不過病人須多挨一針)
Complication
- 感染(Infection)
- 出血(Bleeding)
- 過敏(Allergy)，主要是對關節內注射藥物過敏
Synovial fluid analysis
- 外觀(General appearance):
1)質地:透明、混濁
2)顏色:清澈、黃、紅
usmlepathslides: “ Synovial fluid tubes: From left to right, • normal • noninflammatory (e.g., osteoarthritis) • inflammatory (e.g., rheumatoid arthritis) • septic (e.g., gonococcal septic arthritis) • hemorrhage (e.g., trauma, hemophilia A) ”
- 關節液常規檢查(Joint fluid routine)
1) WBC
#Normal:<200
#Non inflammatory: 200-2000
#Inflammatory:2000-50000
#Septic:>50000
2) Neutrophil count
3) Gram stain
4) Crystal
#Gout: needle shape and negative birefringent
#Pseudogout(calcium pyrophosphate deposit): rhomboid and positive birefringent
