Massive arteriovenous air embolism after computed tomography-guided lung tumour biopsy.

Abstract

A 69-year-old male German patient with a poor English proficiency underwent a computed tomography (CT)-guided needle biopsy of a right upper lung mass at his local hospital (Fig. 1). A 19/20-gauge Cook Quick Core Biopsy Needle Set (Cook Medical, Bloomington, IN, USA) was used. The 19-gauge coaxial access needle was placed through the pleura in a single pass. Placement was confirmed by imaging. The patient was instructed via a family interpreter to hold his breath and the stylet of the coaxial needle was removed prior to obtaining a core sample biopsy of the nodule with the 20-gauge side cutting needle. The patient inhaled deeply as the biopsy needle was being placed into the coaxial needle. The next CT sequence revealed a systemic air embolism involving air in the aorta, superior vena cava and epidural venous plexus (Fig. 2). There was no air in coronary circulation and a head CT confirmed no cerebral air. The biopsy needle was removed and the patient was administered high-flow oxygen and placed in the Trendelenburg’s position. Vital signs were stable, the airways patent and breathing and circulation were adequate. Pupils were reactive to light and of equal size. The patient had normal level of consciousness (Glasgow coma scale score of 15) with intact cranial nerves, upper limbs and right leg neurology. There was reduced sensation to light touch over the left flank and the entire left leg. The patient was then transported to the emergency department. Because the patient’s condition was stable, he was placed back into a supine position. Soon afterwards, he developed sudden onset of abdominal pain, moderately reduced power in right hip flexion (3/5), severely reduced power in the left hip (1/5), knee, ankle and toe flexion and extension (2/5), and acute urinary retention. The patient was returned to the Trendelenburg’s position and catheterized and remained on high-flow oxygen while being transferred by Air Ambulance to a tertiary hospital for urgent hyperbaric oxygen therapy (HBOT). The patient underwent an initial session of HBOT using a maximally extended US Navy Treatment Table 6 protocol, totalling 7 h in the chamber, consisting of compression to 2.8 atmospheres absolute (ATA) (18 m seawater) breathing 100% oxygen for five 20min periods separated by 5-min air breaks, and then two 60-min and two 30-min periods at 1.9 ATA with 15-min air breaks. After this, his abdominal pain had completely resolved. Dramatic improvement in his left leg power was noted after two subsequent daily hyperbaric sessions using the 18:60:30 protocol, which involves compression to 2.8 ATA for 60 min breathing 100% oxygen followed by decompression over a 30-min period. After six daily sessions his leg power was essentially normal, with only mild reduction in left hip flexion, and he was able to walk unassisted, but some subjective sensory dysfunction remained. Although improved, his bladder and bowel dysfunction persisted and he was referred to a specialist spinal unit for rehabilitation in this regard and for further work to improve his gait. Subsequently, the patient underwent a left anterior mediastinotomy and lymph node biopsy followed by thoracoscopic right upper lobectomy for pT2a pulmonary adenocarcinoma, N1, M0. He continued to use infrequent urinary bladder self-catheterization and laxatives. Systemic air embolism after percutaneous CT-guided needle biopsy occurs in 0.2–0.4% of patients and is associated with 26% mortality. Procedure-related variables including avoidance of major pulmonary vessels and the use of a coaxial needle biopsy aspiration system, as well as patient-related risk factors such as coughing and the ability to follow the clinician’s instructions, influence the incidence of this iatrogenic complication. There are two main mechanisms of systemic air embolism during transthoracic needle biopsy. First, atmospheric air can enter the patient’s pulmonary venous circulation on inspiration at the time of the needle stylet removal, and second, air can enter the patient’s pulmonary blood stream via a needle track bronchovenous fistula during coughing, the Valsalva manoeuvre, or positive pressure ventilation. Our patient developed an air embolism via the pulmonary vein–needle–atmosphere communication on deep inspiration. We speculate that the air embolus had gained access to the superior

DOI: 10.1111/ans.14101

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Cite this paper

@article{Beliaev2017MassiveAA, title={Massive arteriovenous air embolism after computed tomography-guided lung tumour biopsy.}, author={Andrei M Beliaev and David G. Milne and Chris Sames and Bruce O'Brien and Tharumenthiran Ramanathan}, journal={ANZ journal of surgery}, year={2017} }