Mahmoud Mohamed, Gunter Joel, Donnelly Lane F, Wang Yu, Nick Todd G, Sadhasivam Senthilkumar
Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
Anesth Analg. 2009 Sep;109(3):745-53. doi: 10.1213/ane.0b013e3181adc506.
Magnetic resonance imaging (MRI) sleep studies can be used to guide management of children with obstructive sleep apnea (OSA) refractory to conservative therapy. Because children with OSA are sensitive to the respiratory-depressant effects of sedatives and anesthetics, provision of anesthesia for imaging studies in this patient population can be challenging. Dexmedetomidine has been shown to have pharmacological properties simulating natural sleep with minimal respiratory depression. We hypothesized that, compared with propofol, dexmedetomidine would have less effect on upper airway tone and airway collapsibility, provide more favorable conditions during dynamic MRI airway imaging in children with OSA, have fewer scan interruptions, and require less aggressive airway interventions.
In this retrospective descriptive study, we reviewed the records of 52 children receiving dexmedetomidine and 30 children receiving propofol for anesthesia during MRI sleep studies between July 2006 and March 2008. Documentation of the severity of OSA by overnight polysomnography was available for 67 of the 82 subjects, who were analyzed separately. Data analyzed included demographics, severity of OSA, comorbidities, hemodynamic changes, use of artificial airways, additional airway maneuvers, and successful completion of the MRI scan.
Demographics, OSA severity by polysomnography, anesthetic induction, and baseline hemodynamics were comparable in both groups. An interpretable MRI sleep study was obtained for 98% of children in the dexmedetomidine group and 100% in the propofol group. Of 82 children, MRI sleep studies were successfully completed without the use of artificial airways in 46 children (88.5%) in the dexmedetomidine group versus 21 children (70%) in the propofol group (P = 0.03). An artificial airway was required to complete the study in five children (12%) in the dexmedetomidine group versus nine children (35%) in the propofol group (P = 0.06). Additional airway maneuvers (chin lift and shoulder roll) were required to complete the study in one child (2%) in the dexmedetomidine group and three children (10%) in the propofol group (P = 0.14). Children in the dexmedetomidine group experienced reductions in heart rate, whereas those in the propofol group experienced reductions in arterial blood pressure; these reductions were statistically, but not clinically, significant.
Dexmedetomidine provided an acceptable level of anesthesia for MRI sleep studies in children with OSA, producing a high yield of interpretable studies of the patient's native airway. The need for artificial airway support during the MRI sleep study was significantly less with dexmedetomidine than with propofol. Dexmedetomidine may be the preferred drug for anesthesia during MRI sleep studies in children with a history of severe OSA and may offer benefits to children with sleep-disordered breathing requiring anesthesia or anesthesia for other diagnostic imaging studies.
磁共振成像（MRI）睡眠研究可用于指导对保守治疗无效的阻塞性睡眠呼吸暂停（OSA）儿童的管理。由于OSA儿童对镇静剂和麻醉剂的呼吸抑制作用敏感，因此为该患者群体的影像学检查提供麻醉可能具有挑战性。右美托咪定已被证明具有模拟自然睡眠且呼吸抑制最小的药理学特性。我们假设，与丙泊酚相比，右美托咪定对上气道张力和气道可塌陷性的影响较小，在OSA儿童的动态MRI气道成像过程中提供更有利的条件，扫描中断更少，并且需要的积极气道干预更少。
在这项回顾性描述性研究中，我们回顾了2006年7月至2008年3月期间52例接受右美托咪定和30例接受丙泊酚进行MRI睡眠研究麻醉的儿童的记录。82名受试者中有67名可通过夜间多导睡眠图记录OSA的严重程度，并对其进行单独分析。分析的数据包括人口统计学、OSA严重程度、合并症、血流动力学变化、人工气道的使用、额外的气道操作以及MRI扫描的成功完成情况。
两组在人口统计学、多导睡眠图显示的OSA严重程度、麻醉诱导和基线血流动力学方面具有可比性。右美托咪定组98%的儿童和丙泊酚组100%的儿童获得了可解释的MRI睡眠研究结果。在82名儿童中，右美托咪定组46名儿童（88.5%）在未使用人工气道的情况下成功完成了MRI睡眠研究，而丙泊酚组为21名儿童（70%）（P = 0.03）。右美托咪定组有5名儿童（12%）需要人工气道来完成研究，丙泊酚组为9名儿童（35%）（P = 0.06）。右美托咪定组有1名儿童（2%）和丙泊酚组有3名儿童（10%）需要额外的气道操作（抬颏和肩部滚动）来完成研究（P = 0.14）。右美托咪定组儿童的心率降低，而丙泊酚组儿童的动脉血压降低；这些降低在统计学上有意义，但在临床上无意义。
右美托咪定为OSA儿童的MRI睡眠研究提供了可接受的麻醉水平，对患者的天然气道进行可解释研究的成功率很高。与丙泊酚相比，右美托咪定在MRI睡眠研究期间对人工气道支持的需求明显更少。右美托咪定可能是有严重OSA病史儿童MRI睡眠研究期间麻醉的首选药物，并且可能对需要麻醉或因其他诊断性影像学检查而进行麻醉的睡眠呼吸障碍儿童有益。
