Table 2.

Variation in serum tryptase concentration in control children undergoing uneventful general anaesthesia. ΔT, intraoperative serum tryptase – baseline serum tryptase; ΔT%, % variation in serum tryptase; bST, baseline serum tryptase; Pre-school, 0–6 yr; School, 6–18 yr. P-values were calculated to compare bST and intraoperative serum tryptase in each subgroup.

	ΔT absolute value (ng ml−1) median (range)	ΔT as a % of bST median (range)	p-value	Total (n)
Total	–0.41 (–3.09 to 7.66)	–15.33 (–70.81 to 123.23)	<0.001	96
Age group  Pre-school  School	–0.51 (–3.09 to 2.33) –0.41 (–1.97 to 7.66)	–14.50 (–70.81 to 52.36) –15.53 (–60.23 to 123.23)	<0.001 <0.001	49 47
Sex  Female  Male	–0.37 (–2.33 to 0.40) –0.46 (–3.09 to 7.66)	–15.36 (–60.23 to 40.38) –15.33 (–70.81 to 123.23)	<0.001 0.004	28 68