Pre-term babies are very delicate, so it is really important that suction pumps are set to give the correct amount of suction pressure, otherwise, you may harm the baby.

Pre-terms actually need a very small amount of pressure. But just to cause confusion, there are two different units commonly used to measure pressure.

The standard unit used on many devices is millimeters of mercury, written mmHg. So a pre-term needs between -60 and -100 millimeters of mercury.

However, on some devices, the pressure is shown in bars. A bar is a completely different unit of measurement.

To convert from millimeters of mercury to bars, you need to divide by 750.062. It is not a sum that you want to try to do in your head.

The important thing to know for suction pumps used in a neonatal unit is that -60 to -100 milligrams of mercury converts to roughly between -0.08 and -0.13 bars. On the Fazzini suction pump, the pressure gauge goes from zero to -1 bar of pressure.

The pressure you need for suctioning babies is therefore the area marked in green. As you can see, it is quite a small area, so the device needs to be able to set the pressure quite accurately.

If the device turns on but you are having problems setting the pressure, then it could be a fault with either the regulator knob or with the pressure gauge.

In this film, we will look at problems with the pressure gauge.

The pressure gauge or vacuum gauge measures the suction pressure inside the machine. It uses a spring-loaded mechanism that moves a needle based on the level of pressure.

Over time, the gauge can become inaccurate. This is known as calibration drift.

If not corrected, this can lead to unsafe pressure readings. In this case, the gauge is not starting at zero, showing an extreme amount of calibration drift. To fix this, we will need to calibrate the gauge by shifting the needle to the correct place.

First, turn off the device and ensure it is disconnected from the mains. Disconnect the downstream tubing by sliding the tubing out of the port.

Now take off the cover from the base and remove all the tubing from the cover by gently pulling it out using your hand.

You can leave in the short tube going to the patient port.

To remove the pressure gauge, access the hex nut from inside the casing.

Use locking pliers to loosen it while holding the gauge from the outside to prevent it from falling.

Once loosened, remove the hex nut by hand. The gauge will then come free.

To recalibrate the gauge, start by removing the protective transparent plastic cover to access the needle.

Hold the gauge firmly and use a flat screwdriver to gently pry the cover open from the side slots, working your way around carefully. Take care not to crack or damage the plastic.

Next, gently lift the needle using the screwdriver and reposition it so it aligns with the zero mark.

Press it down to secure it. Check the alignment by lifting it slightly and ensuring it returns to zero on its own. Once you are happy it is in the right place, put the protective cover back and press it in until it clicks into place. Finally, reinstall the gauge.

Hold it in position from the outside, then secure it from the inside by tightening the hex nut. Once it is secure, you can reconnect the tubing.

The other problem you may face is if the pressure gauge is not moving at all.

Pressure gauges on suction pumps have a curved metal spring, which is quite delicate and can be damaged, particularly if it gets wet or rusted because liquids enter the system.

If the gauge is damaged, it will need replacing. To do this, simply take out the old gauge and put in a new one. Once you have installed the gauge, you then need to reconnect all the tubing and put the device back together. We will show you how to do that in a later film.

Make sure you test the gauge to see if it is working. If you find that it is still not giving any reading, it may be that it is the pressure regulator which is faulty and not the gauge.