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Background and Aims Prosthetic joint infections can be challenging to treat and often require surgical intervention. We present a case of arthroscopic knee washout performed under peripheral nerve blocks due to the high risks of general and neuraxial anaesthesia.

Methods A 75 year old lady presented with an infected prosthesis, two years post total knee arthroplasty. She had a BMI of 40, hypertension, TIA one year ago (currently on Clopidogrel), moderate obstructive spirometry (FEV1 72% predicted), ASD repair 40 years ago and suspicion of pulmonary hypertension on CT thorax. She was positive for COVID-19 on admission. Surgical debridement was delayed due to the risks of both general and regional anaesthesia given her COVID status and anti-platelet medication. Clopidogrel was stopped and she was treated with IV antibiotics. After two days she was at risk of deteriorating; she had significantly elevated inflammatory markers and was repeatedly spiking temperatures. Given her ongoing anaesthetic risks we consented her to have a joint washout under awake peripheral nerve blocks. Ultrasound guided femoral and popliteal nerve blocks were performed with 16ml and 20ml 1% Prilocaine respectively. Aliquots of alfentanil were required intermittently during the procedure to a total of 800mcg, and the patient was reassured throughout.

Results Arthroscopic washout was successfully performed in this patient under femoral and popliteal nerve blocks using 1% Prilocaine, with supplemental intravenous analgesia.

Conclusions Peripheral nerve blocks can be used for washout of infected knee joints, allowing time for optimisation before definitive surgical intervention under neuraxial or general anaesthesia.