When to Use flow meter？

What is a peak flow meter(bn,zu,pt)?

A peak flow meter is a small, handheld device that measures how fast you can push air out of your lungs when you blow out (exhale) as hard and as fast as possible. This is your peak flow. Another name for peak flow is peak expiratory flow measurement.

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There are manual and digital peak flow meters. A manual peak flow meter has markers on the device that you use to track your peak flow. A digital peak flow meter displays your peak flow on a screen.

Peak flow meters come with a chart with average readings. It’s important to remember that you don’t need to aim for these numbers — they’re just an average.

What condition does a peak flow meter help manage?

A peak flow meter helps manage moderate to severe asthma. It measures how open the airways (bronchi) are in your lungs. Your peak flow may drop, even before you have an asthma attack. A drop in your peak flow tells you that your asthma might be getting worse.

How do I use a peak flow meter?

A peak flow meter is simple to use. To measure your peak flow:

• Sit or stand up straight. Standing up may make it easier to breathe deeply. Whichever you choose, make sure you do it this way each time you use a peak flow meter.
• Make sure the marker is at the bottom of the meter.
• Take a deep breath, filling your lungs completely, and hold it. A very deep breath will move your abdominal (belly) muscles, too, not just your chest muscles.
• Put your mouth around the mouthpiece and close your lips tightly. Make sure your lips form a seal so no air escapes around the outside of the mouthpiece.
• Blow all the air out of your lungs as hard and fast as possible in a single exhale.
• Write down the number by the marker on the meter.

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Repeat these steps three times. The highest of these three readings is your daily peak flow. Write down your daily peak flow on a sheet of paper, on your calendar, in your smartphone or in your asthma diary. You should also record:

• Any symptoms you have, including wheezing, chest tightness, shortness of breath or coughing.
• If you’ve taken your rescue inhaler or any other emergency medication (including bronchodilators or anti-inflammatory medicines).

What units does a peak flow meter measure in?

A peak flow meter measures liters per minute (L/min).

How do you find your “personal best” peak flow?

Your personal or usual best peak flow is the highest number you can achieve over a two-week period while your asthma is under good control. “Good control” means you feel good and don’t have any symptoms. You’ll compare your other peak flow readings to your best peak flow number.

To find your personal best peak flow:

• Perform peak flow testing twice a day for two weeks.
• Test at the same time in the morning and early evening.
• Perform the test before taking any inhalers or as instructed by a healthcare provider.

Once you determine your personal best peak flow, continue using your peak flow meter daily or as instructed by a healthcare provider. Regularly using your peak flow meter will help you recognize decreases in your airflow early. This can help guide your asthma treatment. A provider may use these numbers to create an asthma action plan to help manage your symptoms.

What is a normal peak flow meter reading?

It depends. Your “normal” peak flow may differ from another person’s “normal” peak flow. A healthcare provider will help determine your normal peak flow according to your:

• Age. Children have smaller lungs than adults.
• Height. The taller you are, the bigger your lungs.
• Sex. Men usually have bigger lungs than women.

Healthcare providers generally use a “traffic light” system that consists of three zones to determine your peak flow rate:

• Green zone. Your asthma is in good control. Your peak flow is 80% to 100% of your personal best.
• Yellow zone. Your asthma isn’t in good control or is getting worse. Your peak flow is 50% to 80% of your personal best.
• Red zone. Your asthma is severe. Your peak flow is less than 50% of your personal best. You need emergency care.

To find the number ranges for your zones, multiply your personal best peak flow by:

• (100%).
• 0.8 (80%).
• 0.5 (50%).

Record these ranges so you can reference them quickly. For example, if your personal best peak flow is 400 L/m, the zones will be:

• Green zone: 320 to 400 L/m (80% to 100%).
• Yellow zone: 200 L/m to 320 L/m (50% to 80%).
• Red zone: Less than 200 L/m (less than 50%).

If you’re in the yellow or red zones, you must adjust your medicine according to your healthcare provider’s instructions. Use the peak flow values and your symptoms to take action, if necessary. If you have an asthma action plan, make sure you understand and can follow it. Ask a healthcare provider if you have any questions.

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What should your lung capacity be on a peak flow meter?

Your peak flow will vary according to your age, height and sex. Peak flow numbers are usually higher in people who are younger, taller or male.

A normal peak flow in adults may be between 400 and 700 L/m. In children, a normal peak flow may range from around 150 to 450 L/m. Be sure to keep track of your peak flow readings. A healthcare provider can use this information to observe your numbers over time and determine if your results are changing.

What is a bad peak flow meter reading?

If your peak flow is in the yellow or red zones, immediately use your rescue inhaler or other emergency medications. If your peak flow doesn’t improve, call a healthcare provider immediately or go to the nearest emergency room.

Is 250 on a peak flow meter good?

It depends. A reading of 250 L/m may be good for some people but not others. Talk to a healthcare provider if you have questions about your peak flow meter readings.

FULL TRANSCRIPT (with timecode)

00:00:01;24 - 00:00:04;01

How to use a peak flow meter. 

00:00:05;15 - 00:00:08;17

Look at your peak flow meter to make
 sure the mouthpiece is

00:00:08;19 - 00:00:10;21

clean and clear of any
 objects.

00:00:11;22 - 00:00:14;12

Move the marker to the bottom of
 the numbered scale.

00:00:14;18 - 00:00:17;11

You may need to shake it
 to move the marker down.

00:00:18;12 - 00:00:19;29

Stand or sit up straight. 

00:00:21;09 - 00:00:24;10

Take a deep breath in through your
 nose, filling your lungs

00:00:24;12 - 00:00:25;03

all the way. 

00:00:26;25 - 00:00:29;06

Place the device between your teeth
 or gums,

00:00:29;08 - 00:00:30;13

biting down gently. 

00:00:30;25 - 00:00:33;19

Then seal your lips tightly around
 the mouthpiece.

00:00:34;22 - 00:00:38;07

Blow out as hard and as fast
 as you can with a single

00:00:38;09 - 00:00:39;03

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breath or blow. 

00:00:39;29 - 00:00:42;02

Read the number that is
 next to the marker.

00:00:42;13 - 00:00:43;15

Write down the number. 

00:00:44;13 - 00:00:45;21

To reset the meter, 

00:00:45;23 - 00:00:48;23

move the marker back to the bottom
 of the numbered scale

00:00:48;25 - 00:00:51;11

and repeat the same steps two
 more times.

00:00:52;18 - 00:00:54;18

The highest of the three numbers
 is your

00:00:54;20 - 00:00:55;21

peak flow number. 

00:00:56;13 - 00:00:59;02

Write down this number in a notebook
 or tracking chart.

00:00:59;15 - 00:01:02;19

Use the number to monitor your asthma
 and share with your

00:01:02;21 - 00:01:03;21

health care provider. 

00:01:04;18 - 00:01:07;02

If you coughed or did not
 do the steps in the

00:01:07;04 - 00:01:09;21

correct order, do not write down
 the number.

00:01:10;03 - 00:01:13;19

Instead, repeat the steps to get
 three good results.

00:01:14;15 - 00:01:18;03

If you become lightheaded, stop
 and rest and do it later.

00:01:19;06 - 00:01:20;19

Store in a safe place. 

00:01:20;30 - 00:01:22;29

Clean your peak flow
 meter according to

00:01:23;02 - 00:01:24;12

the package instructions. 

People who have asthma can benefit from the use of a peak flow meter, as well as some people with chronic bronchitis and emphysema. A peak flow meter may be most useful for people that are newly diagnosed and those with persistent asthma. If you need to adjust your daily medication for asthma, a peak flow meter can be an important part of your asthma management plan.

A peak flow meter can be especially helpful to use with young children who may not be able to communicate about trouble breathing. Children as young as five are usually able to use a peak flow meter to help manage their asthma.

Step 1: Before each use, make sure the sliding marker or arrow on the Peak Flow Meter is at the bottom of the numbered scale (zero or the lowest number on the scale).

Step 2: Stand up straight. Remove gum or any food from your mouth. Take a deep breath (as deep as you can). Put the mouthpiece of the peak flow meter into your mouth. Close your lips tightly around the mouthpiece. Be sure to keep your tongue away from the mouthpiece. In one breath, blow out as hard and as quickly as possible (like you are blowing out candles on a birthday cake). Blow a "fast hard blast" rather than "slowly blowing" until you have emptied out nearly all the air from your lungs.

Step 3: The force of the air coming out of your lungs causes the marker to move along the numbered scale. Note the number on a piece of paper.

Step 4: Repeat the entire routine three times. (You know you have done the routine correctly when the numbers from all three tries are very close together.)

Step 5: Record the highest of the three ratings. Do not calculate an average. This is very important. You can't breathe out too much when using your peak flow meter, but you can breathe out too little. Record your highest reading.

Step 6: Measure your peak flow rate close to the same time each day. You and your healthcare provider can determine the best times. One suggestion is to measure your peak flow rate twice daily between 7 and 9 a.m. and between 6 and 8 p.m. You may want to measure your peak flow rate before or after using your medicine. Some people measure peak flow both before and after taking medication. Try to do it the same way each time.

Step 7: Keep a chart of your peak flow rates. Discuss the readings with your healthcare provider.

Use of the peak flow meter depends on several things. Its use should be discussed with your healthcare provider.

If your asthma is well controlled and you know the "normal" rate for you, you may decide to measure your peak flow rate only when you sense that your asthma is getting worse. More severe asthma may require several measurements daily.

Don't forget that your peak flow meter needs care and cleaning. Dirt collected in the meter may make your peak flow measurements inaccurate. If you have a cold or other respiratory infection, germs or mucus may also collect in the meter.

Proper cleaning with mild detergent in hot water will keep your peak flow meter working accurately and may keep you healthier.