Australian and New Zealand Anaesthetic Allergy Group/Australian and New Zealand College of Anaesthetists perioperative anaphylaxis management guideline 2022.

Perioperative anaphylaxis is a potentially life-threatening emergency that requires prompt recognition and institution of life-saving therapy. The Australian and New Zealand College of Anaesthetists and Australian and New Zealand Anaesthetic Allergy Group have partnered to develop the anaphylaxis management guideline along with crisis management cards that are recommended for use in suspected anaphylaxis in the perioperative setting. This is the third version of these guidelines with the second version having been published in 2016. This article contains the revised Australian and New Zealand Anaesthetic Allergy Group/Australian and New Zealand College of Anaesthetists perioperative anaphylaxis management guideline, with a brief review of the current evidence for the management of anaphylaxis in the perioperative environment.

Updated guideline on equipment to manage difficult airways: Australian and New Zealand College of Anaesthetists.

The Australian and New Zealand College of Anaesthetists (ANZCA) recently reviewed and updated the guideline on equipment to manage a difficult airway. An ANZCA-established document development group, which included representatives from the Australasian College for Emergency Medicine and the College of Intensive Care Medicine of Australia and New Zealand, performed the review, which is based on expert consensus, an extensive literature review, and bi-nationwide consultation. The guideline (PG56(A) 2021, https://www.anzca.edu.au/getattachment/02fe1a4c-14f0-4ad1-8337-c281d26bfa17/PS56-Guideline-on-equipment-to-manage-difficult-airways) is accompanied by a detailed background paper (PG56(A)BP 2021, https://www.anzca.edu.au/getattachment/9ef4cd97-2f02-47fe-a63a-9f74fa7c68ac/PG56(A)BP-Guideline-on-equipment-to-manage-difficult-airways-Background-Paper), from which the current recommendations are reproduced on behalf of, and with the permission of, ANZCA. The updated 2021 guideline replaces the 2012 version and aims to provide an updated, objective, informed, transparent, and evidence-based review of equipment to manage difficult airways.

Los mitos en torno de la relación entre presión sanguínea y flujo / Myths surrounding the relationship between blood pressure and flow

La hipotensión asociada con la vasodilatación inducida por el uso de agentes anestésicos es muy frecuente, un fenómeno que ha motivado la utilización casi generalizada de vasopresores, con la finalidad de restaurar la presión sanguínea a los niveles registrados antes de la anestesia. En Australia, entre todas las medicaciones que se usan en la anestesia, el costo de los vasopresores es un factor significativo en los costos de los sistemas de salud. La utilización de vasopresores debe basarse en los posibles beneficios y riesgos asociados. Desde hace tiempo se acepta que la presión arterial debe mantenerse con la finalidad de preservar la perfusión. Sin embargo, la evaluación detallada indica que este concepto podría surgir de la interpretación errónea de las leyes básicas de la física, como las leyes de Newton y de Ohm. En este trabajo se propone, en función de los principios de la física, que sólo las fuerzas pueden motivar el aceleramiento de los objetos. Para que la presión sea un conductor del flujo, debería ser una fuerza. Sin embargo, la presión es el resultado de fuerzas que actúan sobre una superficie determinada y, por ende, no representa en sí misma una fuerza y no puede ser un conductor de flujo. El flujo sanguíneo es resultado del equilibrio entre las fuerzas de propulsión y de resistencia; en este contexto se debe reconsiderar el supuesto beneficio de aumentar las fuerzas de resistencia, un fenómeno que, en realidad, motivará una reducción del flujo. En el estudio se cuestiona el uso de vasopresores, como también la relación básica, ampliamente aceptada, entre la presión sanguínea y el flujo sanguíneo.

Hypotension resulting from vasodilatation associated with administration of anaesthetic agents is very common. This has resulted in the almost ubiquitous use of vasopressors with a view to restoring blood pressure to pre-anaesthesia levels. In Australia, of all the medications used in anaesthesia, the cost of vasopressors is a significant factor in contributing to healthcare costs. The rationale for use of vasopressors warrants consideration with regard to their benefits as well as potential harm arising from their use. It has long been accepted that blood pressure needs to be maintained in order to maintain perfusion. However, on close scrutiny such thinking may simply be a misinterpretation of the basic laws of physics with respect to both Newton's laws and Ohm's law. This article develops the physics-based argument that only forces can cause objects to accelerate. For pressure to be a driver of flow it must therefore be a force. However, pressure is the result of forces acting over an area, and consequently is not a force in itself. Therefore, it cannot be a driver of flow. Blood flow is the result of the balance of propulsive and resistive forces, which raises the question as to the benefit of increasing resistive forces, which in fact will reduce flow. The use of vasopressors is challenged in this article as is the basic accepted relationship between blood pressure and blood flow.

Contamination of an Unpreserved Semisoft Baked Cookie with a Xerophilic Aspergillus species.

An Aspergillus mold was isolated that had contaminated an unpreserved semisoft baked cookie with visible mycelial growth. Due to the xerophilic nature of the contaminating mold, the Aspergillus isolate went undetected using conventional plating media and incubation times. Spread plating onto rose bengal osmophilic potato dextrose (rose-osmo) agar, a reduced water activity (aw) medium, was used for isolation and enumeration of the isolate from contaminated cookies and in microbiological assessments of the production facility. Rose-osmo plates were sealed in plastic and incubated at 25°C for up to 6 weeks to allow the isolate to sporulate. The minimum aw that permitted growth was determined by inoculating both MY70GF agar plates and production cookies with fresh spores of the Aspergillus isolate. Inoculated samples were incubated for up to 6 weeks in humidity chambers adjusted to various moisture levels. The minimum aw required for growth of the Aspergillus isolate was found to be between 0.60 and 0.65 on MY70GF agar and approximately 0.65 on the cookie. To evaluate the potential delayed growth of the isolate on reformulated cookies of a lowered aw, long-term growth studies were conducted on cookies adjusted to various aw levels and monitored for up to 280 days. In these studies, the minimum aw test range found to support visible mycelial growth of the Aspergillus isolate was 0.67. Microbiological assessment of the production facility identified potential sources of xerophilic molds and the Aspergillus isolate (teleomorph Eurotium chevalieri ) and identified the manner in which the cookies became contaminated. These methods and results proved helpful in both production and process risk assessments and in successful reformulation of the cookie at an aw low enough to prevent spoilage and provide an organoleptically acceptable product.