水合氯醛对豚鼠听性脑干反应的影响

目的 探讨水合氯醛麻醉对成年豚鼠听性脑干反应检测的影响.方法 分别在清醒状态(w aking state,W)及水合氯醛(chloral hydrate,CH)麻醉状态下对20只健康成年雄性白色豚鼠进行短声(click)诱发的听性脑干反应(auditory brainstem response,ABR)检测,以引出率最高的波来判断反应阈值,比较两种状态下90 dB peSPL刺激声强下ABR各波的潜伏期、波间期及不同强度下的Ⅱ 、Ⅲ 、Ⅳ波振幅及引出率.结果 20只豚鼠水合氯醛麻醉状态与清醒状态下ABR反应阈分别为25.50±2.76、28.5±3.66 dB peSPL,差异无统计学意义(P>0.05).水合氯醛麻醉状态下ABR各波潜伏期较清醒状态均延长,Ⅲ 、Ⅳ 、Ⅴ波差异有统计学意义(P<0.05),而Ⅰ 、Ⅱ波差异无统计学意义(P>0.05);水合氯醛麻醉状态下Ⅰ-Ⅴ 、Ⅲ-Ⅳ 、Ⅳ-Ⅴ波间期较清醒状态下延长(P<0.05),而Ⅰ-Ⅱ 、Ⅱ-Ⅲ波间期差异无统计学意义(P>0.05);水合氯醛麻醉状态和清醒状态均显示波Ⅱ振幅及引出率最高;水合氯醛麻醉状态波Ⅱ 、Ⅲ振幅在高强度刺激声时较清醒状态高,而波Ⅳ振幅较清醒状态低(P<0.05).结论 水合氯醛麻醉及清醒状态下豚鼠ABR反应阈无明显差异,但水合氯醛麻醉会使豚鼠ABR的波Ⅲ 、Ⅳ 、Ⅴ潜伏期明显延长,并对振幅产生影响;豚鼠ABR波Ⅱ出现率最高,可以Ⅱ波判断反应阈.

Chloral Hydrate Effect on Audrtory Brainstem Response in Guinea Pig

Objective To study the effect of chloral hydrate on click sound evoked auditory brainstem re-sponse (ABR) in healthy adult guinea pig .Methods A total of 20 healthy wild type albino male guinea pigs were se-lected for ABR assessment with click sound stimulation conscious and cholral hydrate anesthesia conditions .The ABR threshold was determined according to the wave that presents highest occurrence rate under different stimulus intensity .The latency ,interpeak latency of each wave at 90 dB peSPL stimulation as well as the amplitude of waveⅡ ,Ⅲ ,Ⅳ under different stimulus intensity were recorded .Results The ABR threshold in chloral hydrate anes-thesia was 25 .50 ± 2 .76 dB peSPL and at the waking state was 28 .5 ± 3 .66 dB peSPL from control group (P>0 .05) .The latencies of each wave recorded under chloral hydrate anesthesia state were prolonged compared to those of under waking state ,wave Ⅲ ,Ⅳ and Ⅴ had significance differences (P<0 .05) ,but wave Ⅰ ,Ⅱ had no significant differences (P>0 .05) .The interpeak latency between wave Ⅰ - Ⅴ ,Ⅲ - Ⅳ ,Ⅳ - Ⅴ in chloral hydrate anesthesia were longer compared to those of under waking state with significant differences (P<0 .05) ,while interpeak latency between Ⅰ - Ⅱ ,Ⅱ - Ⅲ had no significant differences (P> 0 .05) .The amplitude and occurrence rate of wave Ⅱwere the highest among all the waves in both experimental group and control group .The amplitude of wave Ⅱ and Ⅲ in chloral hydrate anesthesia was higher than that of the waking state under acoustic stimulation conditions ofhigh intensity(P<0 .05) while the amplitude of wave Ⅳ was lower than the waking state (P<0 .05) .Conclusion The chloral hydrate anesthesia may be able to apparently lengthen the ABR latencies of wave Ⅲ ,Ⅳ ,Ⅴ and affect the amplitude .This effect should be considered during the assessment of ABR under anesthesia state in guinea pig ;The ABR threshold of guinea pig could be determined according to the wave Ⅱ because it 's highest occurrence rate .