- Updated on November 10, 2021
Medical and physiological studies and research articles about BHT (breath holding time) test, or CP (Control Pause), or Buteyko Control Pause, or body oxygen index, or body oxygen level in sick people
Here is a more detailed Table from the web page Breath Holding Time (Oxygenation Index – CP) in Sick People
Abbreviations for Table 5: “max” – maximum; “in” – inhalation; “out” – outhale or exhalation; “norm” – normal.
Table (Low Body-Oxygen Level or Body Oxygen Index in the Sick)
| Condition | # of subj. | CP, s | BHT, s | Test conditions (order of actions before BHT test) | % of BHT for CP | Reference |
| Hypertension | 95 | 12 s | 12 s | Norm out, stress | 100% | Ayman et al, 1939 |
| Neurocircular. asthenia | 54 | 16 s | 40 s | Max in | 40% | Friedman, 1945 |
| Anxiety states | 62 | 20 s | 28 s | Norm in | 73% | Mirsky et al, 1946 |
| Class 1 heart patients | 16 | 16 s | 48 s | Max: in, out, in | 33.3% | Kohn & Cutcher, 1970 |
| Class 2-3 heart patients | 53 | 13 s | 39 s | Max: in, out, in | 33.3% | Kohn & Cutcher, 1970 |
| Pulmonary emphysema | 3 | 8 s | 23 s | Max: in, out, in | 33.3% | Kohn & Cutcher, 1970 |
| Functional heart disease | 13 | 5 s | 15 s | Max: in, out, in | 33.3% | Kohn & Cutcher, 1970 |
| Asymptom. asthmatics | 7 | 20 s | 55 s | Max out, max in | 38 % | Davidson et al, 1974 |
| Asthmatics with sympt | 13 | 11 s | 27 s | Max in | 40 % | Perez-Padilla .., 1989 |
| Panic attack | 14 | 11 s | 34 s | Deep breath:50%O2 | 33.3% | Zandbergen .., 1992 |
| Anxiety disorders | 14 | 16 s | 49 s | Deep breath:50%O2 | 33.3% | Zandbergen .., 1992 |
| Outpatients | 25 | 17 s | 43 s | Max in | 40 % | Gay et al, 1994 |
| Inpatients | 25 | 10 s | 25 s | Max in | 40 % | Gay et al, 1994 |
| COPD or CHF | 7 | 8 s | 21 s | Max in | 40 % | Gay et al, 1994 |
| 12 heavy smokers | 12 | 8 s | 21 s | Max in | 40 % | Gay et al, 1994 |
| Panic disorder | 23 | 16 s | 16 s | Norm out | 100% | Asmudson…, 1994 |
| sleep apnea | 30 | 20 s | 20 s | Norm out | 100% | Taskar et al, 1995 |
| Success. lung transpl. | 9 | 23 s | 23 s | Norm out | 100% | Flume et al, 1996 |
| Success. heart transpl. | 8 | 28 s | 28 s | Norm out | 100% | Flume et al, 1996 |
| Outpatients with COPD | 87 | 8 s | 9.2 s | Norm out, supine | 90% | Marks et al, 1997 |
| Asthma | 55 | 14 s | 24 | Norm out, trained | 60 % | Nannini et al, 2007 |
Notes. “Handbook of physiology”, after analyzing numerous studies, suggested the following proportions for BHT test measurements (Mithoefer, 1965). If BHT test after full inhalation is 100%; then BHT test after normal inhalation is about 55%; BHT after normal exhalation is around 40%; BHT after full exhalation is about 24%. Taking an additional full exhalation or inhalation just before starting the test increases BHT test results by 5 to 15% respectively for each manoeuvre. Those subjects, who have repetitive breath holds many times in a day, experience the “training” effect. It gradually increases maximum BHT (up to 30%), but the BHT test done until the first stress or initial discomfort is not improved after such training. This data allows us to compare different BHT test results done during almost a century of physiological and clinical research investigations, if we chose some standard conditions for the test: the CP or BHT test after quiet or usual expiration and only until the first sensation of air-hunger (a stress-free version of the BHT test). For people who practiced breath holding test many times per day, maximum BHT (for as long as possible) after usual exhalation is around 2 times longer then the CP number due to the “training effect”.
**. Zandbergen et al, 1992 conducted their research experiments with the mixture of about 50% O2 and 50% N2. According to Ferris with his colleagues (1945), this mixture increases normal BHT test by about 50%.
These breath holding time or CP numbers for the sick can be compared with Normal Body-Oxygen Level Results – CP in Healthy People
References for Table 5 (CP in Sick People)
