Arvi Yli-Hankala

This study specifically addressed rebound EEG alterations within slow-wave frequency range upon withdrawal from N₂O in awake healthy participants. Short-term administration of N₂O increased power in theta, but not delta, frequency range upon gas withdrawal and this effect was readily reproduced with repeated dose.

The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the clinical practice guideline Regional anaesthesia in patients on antithrombotic drugs – a joint ESAIC/ESRA guideline. This clinical practice guideline serves as a useful decision aid for Nordic anaesthesiologists providing regional anaesthesia to adult patients on antithrombotic drugs.

The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the clinical practice guideline Surviving sepsis campaign: international guidelines for management of sepsis and septic shock 2021. The guideline serves as a useful bedside decision aid for clinicians managing adults with suspected and confirmed septic shock and sepsis‐associated organ dysfunction.

The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the Living WHO guideline on therapeutics and COVID-19. This trustworthy continuously updated guideline serves as a highly useful decision aid for Nordic anaesthesiologists caring for patients with COVID-19.

The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the clinical practice guideline Transfusion strategies in bleeding critically ill adults: a clinical practice guideline from the European Society of Intensive Care Medicine. This trustworthy clinical practice guideline serves as a useful decision aid for Nordic anaesthesiologists caring for critically ill patients with bleeding.

Background: The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the clinical practice guideline Surviving Sepsis Campaign International Guidelines for the Management of Septic Shock and Sepsis‐Associated Organ Dysfunction in Children. The guideline can serve as a useful decision aid for clinicians managing children with suspected and confirmed septic shock and sepsis‐associated organ dysfunction.

The Clinical Practice Committee of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine endorses the clinical practice guideline New clinical guidelines on the spinal stabilisation of adult trauma patients—consensus and evidence based. The guideline can serve as a useful decision aid for clinicians caring for patients with traumatic spinal cord injury. However, it is important to acknowledge that the overall certainty of evidence supporting the guideline recommendations was low, implying that further research is likely to have an important impact on the confidence in the estimate of effect.

Background: The depth of anesthesia (DOA) is estimated based on the anesthesia-induced electroencephalogram (EEG) changes. However, the surgical environment, as well as the patient him/herself, generates electrical interferences that cause EEG waveform distortion. Case presentation: A 52-year-old patient required general anesthesia due to the right femur necrotizing fasciitis. He had no history of epilepsy or head injury. His cardiovascular status was stable without arrhythmia under propofol and remifentanil anesthesia. The DOA was evaluated with Root® with SedLine® Brain Function Monitoring (Masimo Inc, Irvine, CA). The EEG showed a rhythmic, heart rate time-locked pulsation artifact, which diminished after electrode repositioning. Offline analysis revealed that the pulse wave-like interference in EEG was observed at the heart rate frequency. Conclusions: We experienced an anesthesia case that involves a pulsation artifact generated by the superficial temporal artery contaminating the EEG signal. Numerous clinical conditions, including pulsation artifact, disturb anesthesia EEG.

Purpose: Anesthesiologists have increasingly started to use EEG-based indexes to estimate the level and type of unconsciousness. However, the physiology and biophysics are poorly understood in anesthesiological literature. Methods: EEG was recorded from electrodes on the surface of head, including scalp, as well as DBS (deep brain stimulation) electrodes implanted deep in the brain. Mathematical modeling with a realistic head model was performed to create illustrative images of the sensitivity of electrode montages. Results: EEG pattern of anesthesia, burst-suppression, is recordable outside of scalp area as well in the depth of brain because the EEG current loops produce recordable voltage gradients in the whole head. The typical electrodes used in anesthesia monitoring are most sensitive to basal surface of frontal lobes as well as frontal and mesial parts of temporal lobes. Conclusions: EEG currents create closed-loops, which flow from the surface of the cortex and then return to the inside of the hemispheres. In the case of widespread synchronous activity like physiological sleep or anesthesia, the currents recorded with surface and depth electrodes return through the base of brain and skull.