6-High flow nasal cannula: (Flows up to 8 L/min are used on infants and up to 60 L/min on adults and provide an oxygen percentage of up to 100%) . In patient of hypoxemic respiratory failure, oxygen is applied via variable low-flow systems (e.g., nasal cannula, face masks or non-rebreathing reservoir mask) or high- flow systems (e.g., Venturi masks). These conventional systems have lot of disadvantages. They deliver unreliable fraction of inspired oxygen and provide inadequate warming and humidification of inspired gas. In a patients with acute respiratory failure, peak inspiratory flow rate is high and often exceeds the oxygen flow delivered by these traditional oxygen devices, which results in flow starvation. High-flow nasal cannula (HFNC) oxygen therapy overcomes these limitations. HFNC is a technique of Oxygen which delivers heated and humidified oxygen through a nasal cannula at high flow rates (~60 L/min) at higher oxygen concentration (FiO2 21%–100%) To ensure adequate flow rates, set the flowmeter to a rate that delivers a total flow of at least 40 L/min. Increasing the flow on the device does not increase delivered FiO2. , It only increases the total flow. Set High flow nasal cannula on FiO2 60% or higher may deliver a total flow rate less than 25–30 L/min.(because to increase Fio2 you should decrease the flow from the sitting or increase the flow from the flowmeter) ,Thereby it will not meet the patient’s inspiratory demands. To ensure adequate flow rate on a device along with high percentage of oxygen it is always better to use two flowmeters connected together instead of one.what is peak inspiratory flow in text
In the text, "peak inspiratory flow rate" refers to the maximum rate at which a patient inhales during breathing. It is particularly relevant in the context of patients with acute respiratory failure, where the demand for oxygen can exceed the flow delivered by traditional oxygen delivery systems. This high peak inspiratory flow rate can lead to "flow starvation," meaning that the patient may not receive enough oxygen to meet their respiratory needs. High-flow nasal cannula (HFNC) therapy is designed to address this issue by providing heated and humidified oxygen at high flow rates, ensuring that the oxygen delivery meets the patient's inspiratory