Primary and secondary postoperative hemorrhage in pediatric tonsillectomy

Table 1 The characteristics of the primary and secondary bleeding groups were compared with those of the nonbleeding group separately

Variables	Non-bleeding group, n = 4923	Primary bleeding group, n = 31			Secondary bleeding group, n = 61
		n	χ2	P value	n	χ2	P value
Sex
Female	1543	10	0.012	0.913	19	0.01	0.974
Male	3380	21			42
Age in yr
≤ 6	2763	18	0.047	0.828	19	15.242	0.000a
> 6	2160	13			42
Time of onset in yr
≤ 1	1759	10	0.162	0.688	14	4.293	0.038a
> 1	3164	21			47
Diagnosis
Chronic tonsillitis	1200	8	0.034	0.853	19	1.496	0.221
Tonsil hypertrophy	3723	23			42
Tonsillectomy
Monopolar electrical tonsillectomy	2500	9	5.830	0.016a	24	3.154	0.076
Coblation tonsillectomy	2423	22			37
Surgeon
Junior surgeon	1905	19	6.621	0.010a	25	0.133	0.715
Senior surgeon	3018	12			36
Time when the surgery started
Before noon	2010	10	0.937	0.333	23	0.243	0.622
After noon	2913	21			38
Monthly average air temperature
≤ 20 °C	2315	15	0.023	0.880	24	1.427	0.232
> 20 °C	2608	16			37

Junior surgeon: Surgeon with less than 5 years of experience; Senior surgeon: Surgeon with more than 5 years of experience.

^aP < 0.05.