Clamp-on flow meters help manage increased demand

Since the start of the COVID-19 global pandemic, NHS Trusts have experienced significant concerns around oxygen system deficiencies, especially with the increased use of high flow oxygen devices such as ventilators, and the significant increase in ICU beds across NHS hospitals.

Here, Andy Hammond, MD at Flexim Instruments UK, part of a privately-owned German manufacturer of non-invasive clamp-on flow metering, discusses the importance of achieving actual dynamic flow measurement at various delivery and take-off points in the piped oxygen delivery system, emphasising that the resulting real-time data can be used to help ensure efficient bed management and patient care by clinical staff.

The unprecedented COVID-19 oxygen demand has led to a genuine concern that existing oxygen systems are vulnerable to bottlenecks in supply pipework, or, worse still, overloading the VIE without advance warning, a situation with potential risk to life. Vacuum Insulated Evaporators (VIEs) driven at maximum delivery capacity of the evaporators and control panel are often operating at the edge of specification limits. Systems designed for ‘normal’ oxygen demand rates have quite simply insufficient capability to accommodate high, continuous flows, leading to overload, system freeze-up – resulting in evaporator inefficiency, and consequent oxygen delivery capacity limitations. Fortunately, oxygen capacity at most hospitals has largely been confirmed as at least adequate, with other, inherent, system design problems – such as inadequately sized (too small bore) copper pipework, and distribution system leakage and waste (excessive boil off), being responsible for the systems’ inability to support the number of increased patient ventilators with sufficient oxygen.