Asthma Severity
| Days with Symptoms | Nights with Symptoms | PEF or FEV1 | PEF variability | |
| Severe Persistent | Continual | Frequent | <60% | >30% |
| Moderate Persistent | Daily | >5/mo | 61-70% | >30% |
| Mild Persistent | 3-6x/wk | 3-4x/mo | >80% | 20-30% |
| Mild Intermittent | <2x/wk | <2mo | >80% | <20% |
Predicted Peak Flow
|
Age |
Height |
||||
| (Years) |
60"
|
65"
|
70"
|
75"
|
80"
|
|
20
|
554
|
602
|
649
|
693
|
740
|
|
25
|
543
|
590
|
636
|
679
|
725
|
|
30
|
532
|
577
|
622
|
664
|
710
|
|
35
|
521
|
565
|
609
|
651
|
695
|
|
40
|
509
|
552
|
596
|
636
|
680
|
|
45
|
498
|
540
|
583
|
622
|
665
|
|
50
|
486
|
527
|
569
|
607
|
649
|
|
55
|
475
|
515
|
556
|
593
|
634
|
|
60
|
463
|
502
|
542
|
578
|
618
|
|
65
|
452
|
490
|
529
|
564
|
603
|
|
70
|
440
|
477
|
515
|
550
|
587
|
|
Age |
Height |
||||
| (Years) |
55"
|
60"
|
65"
|
70"
|
75"
|
|
20
|
390
|
423
|
460
|
496
|
529
|
|
25
|
385
|
418
|
454
|
490
|
523
|
|
30
|
380
|
413
|
448
|
483
|
516
|
|
35
|
375
|
408
|
442
|
476
|
509
|
|
40
|
370
|
402
|
436
|
470
|
502
|
|
45
|
365
|
397
|
430
|
464
|
495
|
|
50
|
360
|
391
|
424
|
457
|
488
|
|
55
|
355
|
386
|
418
|
451
|
482
|
|
60
|
350
|
380
|
412
|
445
|
475
|
|
65
|
345
|
375
|
406
|
439
|
468
|
|
70
|
340
|
369
|
400
|
432
|
461
|
|
Height
(inches) |
Males &
Females |
|
43"
|
147
|
|
44"
|
160
|
|
45"
|
173
|
|
46"
|
187
|
|
47"
|
200
|
|
48"
|
214
|
|
49"
|
227
|
|
50"
|
240
|
|
51"
|
254
|
|
52"
|
267
|
|
53"
|
280
|
|
54"
|
293
|
|
55"
|
307
|
|
56"
|
320
|
|
57"
|
334
|
|
58"
|
347
|
|
59"
|
360
|
|
60"
|
373
|
|
61"
|
387
|
|
62"
|
400
|
|
63"
|
413
|
|
64"
|
427
|
|
65"
|
440
|
|
66"
|
454
|
*Leiner GC. et al: Expiratory peak flow rate. AM Rev Respir Dis 88:644, 1963.
1 Polgar G. Promadhat V: Pulmonary Function
Testing in Children: Techniques and
Standards. Philadelphia, W.B. Saunders Company, 1971.
Generalized Example of Asthma Flare Plan
| Zone | Interpretation | Action |
| Green Zone 80-100% predicted PEF |
Good Control | No change needed |
| Yellow Zone 50%-79% predicted PEF |
Inadequate Control | Add rescue medications; Increase dose of controllers |
| Red Zone <50% predicted PEF |
Medical Emergency | Add or increase rescue medications; call physician immediately |