Venous and paradoxical air embolism in the sitting position. A prospective study with transoesophageal echocardiography

Abstract

This prospective study investigates the frequency of patent foramen ovale (PFO), venous air embolism (VAE) and paradoxical air embolism (PAE) by transoesophageal echocardiography (TOE) in neurosurgical patients operated on in the sitting position. The risk of PAE after exclusion of PFO is assessed. A PFO was identified by pre-operative TOE and VAE and PAE by continuous intraoperative TOE. Sixty-two patients were divided into two groups, 22 patients were studied in group 1 (posterior fossa surgery) and group 2 (cervical surgery) contained 40 patients. Pre-operative TOE demonstrated a PFO in 5 of the 22 patients in group 1 (23%). Patients with proven PFO were excluded from the sitting position. Two further patients of this group (12% of 17 patients), in whom a PFO had been excluded pre-operatively, nevertheless had PAE, air occurring in all cavities of the heart. In group 2 the incidence of PFO was 4 out of 40 patients (10%). No PAE was observed in this group. Three morphological types of VAE with different haemodynamic and ventilation changes were demonstrated. VAE was observed in 76% of all posterior fossa operations and in 25% of cervical laminectomies. We conclude that a pre-operative search for PFO is mandatory considering its incidence of 23% in group 1 and of 10% in group 2, and the risk of PAE. If a PFO is detected, the sitting position should be avoided. A residual risk for PAE remains despite exclusion of PFO because the reliability of TOE is limited. TOE is the method of choice for detecting VAE and PAE.

Distribution of artifactual gas on post-mortem multidetector computed tomography (MDCT)

“…venous pressure at the site of intervention [3] or gas forced under pressure into a body cavity [4]. Air embolism can be confirmed in three different ways: precordial ultrasound Doppler, transesophageal echocardiography, and multidetector computed tomography (MDCT).…”

Management of Inadvertent Injury to Superior Sagittal Sinus in Parasagittal Meningioma: Technical Note

“…The upper end of high risk was reported in posterior fossa surgery performed in the sitting position. The risk drops significantly in horizontal positions to a range between 1.4% and 12% [3,11,12].…”

Fatal venous air embolism in swine during surgical procedure

“…Εμβολές με αέρα στον άνθρωπο έχουν παρατη ρηθεί κατά τη διάρκεια νευροχειρουργικών επεμβά σεων (Buckland and Manners 1976, Albin et al 1978, Papadopoulos et al 1994 ιδιαί τερα όταν ο ασθενής βρίσκεται σε καθιστή θέση (Porter et al 1999) και σε πολΰ μικρότερη συχνότητα όταν ο ασθενής βρίσκεται σε πρηνή ή ΰπτια θέση (Albin et al 1991).…”