Short reflex expirations (expiration reflexes) induced by mechanical stimulation of the trachea in anesthetized cats

Cough

Table 1 The parameters of short reflex expirations induced by mechanical stimulation of the trachea (ERt) and expiration reflexes from the glottis (ERg).

	ERt	ERg	p (test)
Number of cats	50	31
Excitability (responses/trials)	67.6%	99.5%	< 0.001 (F)
Cats with several ERt/ERg ≥ 0.2 kPa	28 (out of 50)	27 (out of 31)	< 0.01 (F)
Duration of ABD	63 ± 3 ms	70 ± 3 ms	NS (t)
T (onset of ABD – ABD peak)	36 ± 3 ms	39 ± 2 ms	NS (t)
Relative amplitude of ABD	36 ± 4%	60 ± 9%	< 0.02 (W)
Expiatory pressure amplitude	0.49 ± 0.04 kPa	1.02 ± 0.16 kPa	< 0.01 (W)
Number of cats – PCA	23	22	NS (F)
T (onset of PCA – ABD peak)	52 ± 3 ms	61 ± 4 ms	NS (t)
T (peak of PCA – ABD peak)	14 ± 2 ms	25 ± 4 ms	< 0.02 (W)
T (ABD peak – offset of PCA)	24 ± 3 ms	18 ± 6 ms	NS (W)
Relative amplitude of PCA	67 ± 12%	137 ± 23%	< 0.001 (M)
Number of cats – ThAr	20	22	NS (F)
T (onset of ThAr – ABD peak)	77 ± 4 ms	74 ± 6 ms	NS (W)
T (peak of ThAr – ABD peak)	44 ± 3 ms	43 ± 3 ms	NS (t)
T (ABD peak – minimum of ThAr)	7 ± 4 ms	21 ± 8 ms	NS (W)
T (ABD peak – 2^nd peak of ThAr)	140 ± 20 ms	130 ± 10 ms	NS (W)
T (ABD peak – offset of ThAr)	440 ± 40 ms	730 ± 60 ms	< 0.001 (W)
Relative amplitude of 1^st ThAr peak	83 ± 10%	385 ± 77%	< 0.001 (W)
Relative amplitude of 2^nd ThAr peak	85 ± 20%	311 ± 70%	< 0.01 (W)

ABD, PCA, and ThAr, EMG activities of abdominal, posterior cricoarytenoid, and thyroarytenoid muscles during ERt or ERg; T (onset of ABD – ABD peak), the time interval from the beginning of the burst of ABD to the moment when the maximum of the moving average was reached (amplitude of ABD moving average); other time intervals (T) were measured as described in the table; p (test), the level of statistical significance and in brackets the appropriate test used; NS, non-significant (p > 0.05); F, Fisher's test; t, unpaired t-test; W, Welch corrected unpaired t-test; M, Mann-Whitney test.