Abstract: Objective To investigate the effect of dexmedetomidine(DEX) combined with nalmefene hydrochloride in laryngeal mask anesthesia on the quality of resuscitation and stress indicators in children undergoing appendectomy. 
Methods A total of 98 children who underwent appendectomy in our hospital were selected. Of them, 42 children who received DEX combined with nalmefene hydrochloride for laryngeal mask anesthesia were included in the combination group, and 56 children who underwent laryngeal mask anesthesia were included in the control group. The operative conditions, intraoperative stress response, postoperative resuscitation quality, mental status and complications were compared between two groups. 
Results The awake time, laryngeal mask removal time, spontaneous breathing time, time of off-bed activity, anal exhaust time, and length of hospital stay in the combination group were significantly shorter than those in the control group(P＜0.05). Norepinephrine(NE), adrenaline(E), cortisol(Cor), and adrenocorticotropic hormone(ACTH) levels in two groups after surgery were significantly higher than those at T0, while the NE and E levels at T2 and T3 in the combination group were significantly lower than those in the control group at T1, suggesting no significant difference between the two groups(P＞0.05). The levels of fever Cor and ACTH at T1, T2, and T3 in the combination group were significantly lower than those in the control group(P＜0.05). There was no significant difference in Ramsay and FLACC scores between two groups of children at 5 min after the mask removal(P＞0.05). The Ramsay and FLACC scores of the two groups were significantly reduced at 30 min and 60 min after the mask removal, and the Ramsay score and FLACC score of the combination group were significantly lower than those of the control group(P＜0.05). The mental state of children in the combination group was significantly better than that of the control group(P＜0.05); The incidence of postoperative complications in two groups was not significantly different(P＞0.05). 
Conclusion DEX combined with nalmefene hydrochloride for laryngeal mask anesthesia in children undergoing appendectomy can help shorten the anesthesia recovery time, reduce the children′s stress response, improve the quality of postoperative recovery, and ease the postoperative pain, with good safety and reliability.

Key words: appendectomy, dexmedetomidine, nalmefene