小剂量芬太尼对七氟烷麻醉中小儿自主呼吸的影响

The effect of low-dose fentanyl on children's respiratory function during sevoflurane inhalation

目的 观察小剂量芬太尼对七氟烷麻醉中小儿自主呼吸功能的影响。方法 选择ASAⅠ~Ⅱ级拟择期于全麻下行斜视手术的患儿60例,随机分为Ⅰ、Ⅱ组,均吸入8%七氟烷诱导并置入喉罩;3%七氟烷维持麻醉,保留自主呼吸。Ⅱ组在手术开始前静脉滴注1μg/kg芬太尼,Ⅰ组则给予生理盐水1 ml。记录给予芬太尼或生理盐水前（0 min）,给药后5 min、10 min、15 min、20 min时的脉搏血氧饱和度（SpO2）、潮气量（VT）、呼吸频率（f）、呼气末二氧化碳分压（PETCO2）。于给药前,给药后20 min和停药后15 min测动脉血气。记录患儿苏醒时间和苏醒期躁动情况。结果Ⅱ组患儿苏醒时间长于Ⅰ组[（9.48±1.99）min vs.（6.53±1.29）min,P﹤0.05],躁动发生率低[13.3%（4例）vs.40.0%（12例）]。Ⅱ组患儿的呼吸频率在给药后5 min开始减慢,潮气量表现为抑制或代偿性增加,分钟通气量降低。给药后10 min均表现为呼吸频率减慢和潮气量代偿性增加,20 min时恢复至给药前水平。Ⅱ组患儿动脉二氧化碳分压（PaCO2）和PETCO2升高,pH值降低,苏醒期恢复至给药前水平。结论 1μg/kg芬太尼使七氟烷麻醉时小儿的呼吸频率减慢,潮气量代偿性增加,最终使分钟通气量下降,导致一过性高碳酸血症,多无需处理。PETCO2监测有助于术中呼吸管理。

Objective To evaluate the effects of low-dose fentanyl on children＆#39;s respiratory function during sevoflurane inhalation with spontaneous ventilation. Methods Sixty children scheduled to receive squint correction opera-tion were randomly assigned into two groups. All children were performed anesthetic induction with 8% sevoflurane and 5%oxygen followed by laryngeal mask airway（LMA） insertion. Anesthetic maintenance was performed with 3% sevoflurane and 2%oxygen, which allowed spontaneous ventilation. 1μg/kg fentanyl in group Ⅱ, or saline in groupⅠwas injected in-travenously before the operation. The respiratory parameters and blood gas data were recorded before and after medication in both groups. Recovery time and emergency agitation were evaluated after sevoflurane inhalation. Results There was no difference in operation time between the two groups. Recovery time in group Ⅱ [（9.48 ±1.99）min] was longer than that in groupⅠ [（6.53±1.29 ）min, P﹤0.05]. The incidence of emergency agitation was lower in group Ⅱ （13.3%） compared with groupⅠ （40.0%）. Two cases in group Ⅰreceived drug intervention with propofol. There was no change in respiratory pa-rameters after saline injection in group Ⅰ. Respiratory frequency started to decrease 5 min after medication in group Ⅱwhen tidal volume was decreased in some children and compensatory increased in others. The minute ventilation was de-creased significantly after fentanyl usage. All the children in group Ⅱ showed decreased respiratory frequency and com-pensatory increased tidal volume 10 min after medication, which returned to the level of premedication 20 min af-ter medication. Fentanyl didn＆#39;t cause significant change on PaO2. But PETCO2 and PaCO2 were increased and pH was de-creased correspondingly. There was no need to intervene. Conclusion 1μg/kg fentanyl depresses children＆#39;s spontaneous respiratory function partially during sevoflurane inhalation, which may lead to transient hypercapnia. The P ETCO2 monitor is useful for children＆#39;s ventilation management.