The humidification process of medical gases plays a crucial role in both invasive and non-invasive ventilation, aiming to mitigate the complications arising from bronchial dryness. While passive humidification systems (HME) and active humidification systems are prevalent in routine clinical practice, there is a pressing need for further evaluation of their significance. Additionally, there is often an incomplete understanding of the operational mechanisms of these devices. The current review explores the historical evolution of gas conditioning in clinical practice, from early prototypes to contemporary active and passive humidification systems. It also discusses the physiological principles underlying humidity regulation and provides practical guidance for optimizing humidification parameters in both invasive and non-invasive ventilation modalities. The aim of this review is to elucidate the intricate interplay between temperature, humidity, and patient comfort, emphasizing the importance of individualized approaches to gas conditioning.

Background: The nasogastric tube (NGT) is a widely used tool in the intensive care unit for managing critically ill patients in acute phases and ongoing care. Its application is necessary for evaluating or draining gastric residual volume and administering medications and enteral nutrition. It is typically inserted using a blind technique, and if improperly placed, it can lead to complications, even death. For this reason, over time, various verification methods have been developed to identify the correct positioning of the NGT tip in the stomach, thereby excluding tracheobronchial, esophageal, and duodenal placements. Given the critical nature of NGT placement and verification, direct visualization techniques have been developed in recent years, allowing for immediate confirmation of its correct positioning. Purpose of the Manuscript: The text describes practical techniques for the placement and verification of the NGT, presenting both blind techniques and direct vision techniques. Additionally, the text aims to provide an in-depth analysis on the ultrasonographic technique. Conclusions: Regarding the classical techniques for verifying NGT placement, X-ray remains the gold standard. However, clinical advancements are increasingly steering toward the use of direct visualization techniques. Among these, the most widely used and applicable in intensive care units is the ultrasound technique, which has enhanced operators' ability to place and verify NGTs.