CASE PRESENTATION – PATIENT 1:
An 88-year old female was scheduled for a low anterior resection and end-colostomy formation for a high grade invasive recto-sigmoid adenocarcinoma. She had suffered an acute kidney injury attributable to the mass effect of the tumour involving the bladder that required a rigid cystoscopy and stent insertion prior to laparotomy. Her past medical history included low body mass index, shingles, recurrent urinary tract infection, uterine prolapse and a single functioning kidney. Prior to her admission, she lived at home alone and was fully independent. She did not take any regular medications and had no known drug allergies. Her pre-operative bloods results demonstrated an iron-deficiency anaemia (Haemoglobin 10g/dL), acute kidney injury and raised inflammatory markers consistent with a contained colonic perforation. Coagulation studies were normal. She had been receiving a daily prophylactic dose of enoxaparin (20mg) in the preoperative period.
Prior to induction of anaesthesia, a 20G arterial catheter (Arterial Leader Cath (PE), Vygon Ref 115.090, 3Fr- L.8 cm-0.9 mm-24 ml/min) was inserted in the left radial artery using the Seldinger technique. The first attempt was successful and the arterial catheter was introduced without resistance. Blood could be withdrawn and a normal pulse tracing was shown on the monitor. No discoloration of the hand was noted. General anaesthesia was initiated uneventfully and the patient was positioned on the surgical table in lithotomy with all necessary padding and safety straps applied. All pressure areas including venous and arterial lines were padded and protected. There were no intra-operative issues with the arterial catheter. The surgery concluded after approximately five hours without any complications and minimal estimated blood loss.
At the end of the procedure, progressive dampening of the arterial line trace was noted on the monitor and blood could not be aspirated through it. On removal of the surgical drapes, the left hand was noted to be cold and pale with a prolonged capillary refill time of five seconds. The arterial catheter was disconnected from the transducer tubing and there was evidence of thrombus lodged in the catheter. The catheter was promptly removed and the hand was actively warmed. The patient was extubated and transferred to the recovery room where an urgent consultation with a vascular surgeon was obtained. On further examination, sensation and motor function in the left hand were intact. Doppler ultrasound examination was unable to detect radial, ulnar or palmar arch pulsations adequately. The brachial pulse was detectable.
Following on immediate advice from vascular and colorectal surgical colleagues, treatment with a heparin infusion was not favoured following major abdominal surgery. CT angiography was contraindicated due to her acute kidney injury. Surgical intervention was deemed infeasible. After obtaining consent from the patient, a left-sided stellate ganglion block was performed by an experienced pain specialist. After two hours, the patient’s hand colour and temperature improved with a commensurate reduction in capillary refill time. The patient was transferred to the high dependency unit for ongoing post-surgical observation and was reviewed by the vascular team on a daily basis thereafter.
Within 24 hours, doppler signals in the left radial and ulnar branches were detectable. The fourth and fifth digits remained cold to touch, with intact sensation, for a further 48 hours. Subsequently there was full resolution of symptoms with no requirement for further intervention.