S.P. Gatt

‘Failed supraglottic airway’: an algorithm for suboptimally placed supraglottic airway devices based on videolaryngoscopy

Anaesthetists would not accept malpositioned tracheal tubes resulting in leak, inadequate ventilation, high airway pressures, or one-sided lung ventilation. Yet it is our impression that many, if not the majority, of surgeries are conducted with blindly placed and suboptimally sited supraglottic airway devices (SADs). The anaesthetic community appears to accept much lower standards for SAD placement than for tracheal tube placement.

Continuing to excel in anaesthesia through the ‘big five’: teaching, training, testing, quality, and research

A. A. J. Van Zundert1,*, S. P. Gatt2 and R. P. Mahajan3 1 Department of Anaesthesia and Perioperative Medicine, Royal Brisbane and Women’s Hospital – The University of Queensland, Butterfield Street, Herston, Brisbane, QLD 4029, Australia, 2 Department of Anaesthesia, Prince of Wales Hospital, University of NSW, Sydney, NSW, Australia, and 3 Department of Anaesthesia and Intensive Care, University of Nottingham, Nottingham, UK

Electron Microscopy of Dural and Arachnoid Disruptions After Subarachnoid Block

Background It has been customary to attribute postdural puncture headache (PDPH) incidence and severity to size and nature of the dural hole produced during major neuraxial blockade or diagnostic dural puncture. Needle orientation in relation to the direction of dural fibers was thought to be of importance because of the propensity for horizontal bevel placement to cause cutting rather than splitting of the dural fibers. Methods In vitro punctures of stringently quality-controlled human dural sac specimens were obtained with 27-gauge (27G) Whitacre needle (n = 33), with 29G Quincke used parallel to the spinal axis (n = 30), and with 29G Quincke in perpendicular approach (n = 40). The samples were studied with a scanning electron microscope, and the perimeter, appearance, and area (%) of the lesion were calculated. Results When using small 27G to 29G needles, neither needle tip characteristics nor needle orientation had a substantial bearing on the damage to dural fibers in the dural lesion. Of ultimate importance was the characteristic and size of the hole in the arachnoid. Arachnoid layer lesions produced by different types of spinal needles were not markedly different. Conclusions Accepted theories of the etiology of PDPH need to be revised. This article marks the first time that arachnoid layer damage has been quantified. Dural fibers tend to have sufficient “memory” to close back the hole created by a spinal needle, whereas arachnoid has diminished capacity to do so. The pathogenesis of PDPH and its resolution algorithm are a far more complex process that involves many more “stages” of development than hitherto imagined.