Follow-up strategy for early detection of delayed pseudoaneurysms in patients with blunt traumatic spleen injury: A single-center retrospective study

Table 2 Characteristics of patients classified by the American Association for the Surgery of Trauma spleen injury grade and treatment methods

AAST grade	Number of patients, n	ISS, mean ± SD	NOM		Splenectomy, n (%)
			Close observation, n (%)	Angioembolization, n (%)
I	57	18.39 ± 9.96	47 (82.5)	5 (8.8)	5 (8.8)
II	114	18.80 ± 10.7	84 (73.7)	23 (20.2)	7 (6.1)
III	89	17.80 ± 10.22	25 (28.1)	59 (66.3)	5 (5.62)
IV	50	21.60 ± 8.01	4 (8)	36 (72)	11 (22)
V	13	27.23 ± 5.53	3 (23.1)	3 (23.1)	7 (53.85)

AAST: American Association for the Surgery of Trauma; ISS: Injury severity score; NOM: Nonoperative management.