临床医学进展  >> Vol. 11 No. 2 (February 2021)

超声心输出量监测仪(USCOM)在重症肺炎合并脓毒性休克患儿血流动力学评估和治疗中的应用
Ultrasonic Cardiac Output Monitor (USCOM) Application in Severe Pneumonia Complicated Septic Shock of Hemodynamic Assessment and Treatment in Children

DOI: 10.12677/ACM.2021.112102, PDF, HTML, XML, 下载: 43  浏览: 75 

作者: 庞晓飞:青岛大学医学部,山东 青岛;宋爱琴:青岛大学附属医院,山东 青岛

关键词: 超声心输出量监测仪(USCOM)重症肺炎脓毒性休克血流动力学儿童

摘要: 目的:探讨超声心输出量监测仪(USCOM)对重症肺炎合并脓毒性休克患儿病情评估及指导治疗的应用价值。方法:选取2019年1月~2020年5月由门急诊收至青岛大学附属医院儿科重症医学科住院,诊断为重症肺炎合并脓毒性休克的患儿。行USCOM血流动力学监测患儿作为观察组,以同期未给予USCOM监测且资料完整患儿作为对照组。两组均按照儿童社区获得性肺炎与脓毒性休克诊疗常规治疗,观察组除接受常规治疗外,还根据USCOM监测数据调整液体入量及血管活性药物。观察组记录液体复苏及血管活性药物治疗前后的血流动力学参数并进行比较。记录并比较两组患儿液体入量及血管活性药物用量。比较两组患儿并发症发生率、机械通气时间、转为非危重病例时间、PICU住院时间和病死率。结果:① 截至2020年5月31日,共纳入病例57例,观察组29例,对照组28例。两组治疗前一般情况差异无统计学意义(P > 0.05)。② 观察组给予液体干预患儿共29例,治疗后HR、CI、SVRI、SVI、FTc、SMII均改善,较治疗前差异有统计学意义(P < 0.05);给予血管活性药物干预患儿共12例,治疗后HR、CI、SVRI、SVI、FTc、SMII均显著好转,较治疗前差异有统计学意义(P < 0.05)。③ 观察组液体复苏29例,液体量(43.7 ± 8.33 ml/kg);对照组28例,液体量(54.59 ± 6.15 ml/kg)。观察组应用多巴胺12例,用量(47.2 ± 4.76 mg/kg);对照组15例,用量(69.63 ± 7.45 mg/kg),观察组复苏液体入量及血管活性药物用量均少于对照组,差异有统计学意义(P < 0. 05)。④ 观察组并发症发生率、机械通气时间、转为非危重病例时间均少于对照组,差异有统计学意义(P < 0.05);两组PICU住院时间及病死率差异无统计学意义(P > 0.05)。结论:USCOM操作简便,能够精准评估重症肺炎合并脓毒性休克患儿血流动力学状态,个体化指导容量管理及血管活性药物应用,具有重要临床应用及推广价值。
Abstract: Objective: To evaluate the application value of ultrasonic cardiac output monitor (USCOM) on children with severe pneumonia complicated septic shock in condition assessment and diagnosis and treatment. Methods: Select January 2019 to May 2020 diagnosed as children with severe pneumonia complicated septic shock, admitted through the outpatient and emergency to Department of Pediatric Intensive Care Medicine, the Affiliated Hospital of Qingdao University. Using USCOM hemodynamic monitoring children as observation group, without giving USCOM monitoring children with complete data the same period as control group. Two groups are given treatment in accordance with community-acquired pneumonia in children with routine therapy of septic shock diagnosis, the observation group in addition to conventional treatment, also according to the USCOM monitoring data adjust the amount of liquid and vascular active drugs. The observation group compares the hemodynamic indicators before and after treatment. Record and compare the fluid resuscitation and vascular active drug dosage before and after treatment of two groups. Compare two groups of children with complications, mechanic ventilation time, into the non-severe cases, PICU hospitalization time and mortality. Results: ① As of May 31, 2020, 57 cases were included, observation group 29 cases, control group 28 cases. The general information two groups before treatment has no statistically significant difference (P > 0.05). ② The observation group was given liquid intervention with 27 cases. The HR, CI, SVRI, SVI, FTc SMII after treatment are improved compared with those before treatment, and the differences had statistically significant (P < 0.05). The observation group was given vascular active drug intervention with 12 cases. The HR, CI, SVRI, SVI, FTc SMII after treatment are significant improved compared with those before treatment,and the differences had statistically significant (P < 0.05). ③ There are 29 cases in observation group application liquid recovery, liquid volume (43.7 ± 8.33 ml/kg), 28 cases in the control group, the liquid volume (54.59 ± 6.15 ml/kg). There are 12 cases in observation group application dopamine, dosage (47.2 ± 4.76 mg/kg). 15 cases in the control group, dosage (69.63 ± 7.45 mg/kg), the observation group recovery liquid intake and vascular active drug dosage is less than the control group, the differences had statistically significant (P < 0.05). ④ The complication rate, mechanic ventilation time, into the non-severe cases time of observation group were less than the control group, the differences had statistically significant (P < 0.05). Two groups in PICU hospitalization time and mortality had no statistical significance difference (P > 0.05). Conclusion: USCOM is easy to operate, can accurately evaluate hemodynamic status in children with severe pneumonia with septic shock, individualized instruction capacity management and vascular active drug application, has the important clinical application and popularization value.

文章引用: 庞晓飞, 宋爱琴. 超声心输出量监测仪(USCOM)在重症肺炎合并脓毒性休克患儿血流动力学评估和治疗中的应用[J]. 临床医学进展, 2021, 11(2): 714-721. https://doi.org/10.12677/ACM.2021.112102

1. 引言

肺炎是儿科最常见的疾病之一,由于儿童呼吸系统解剖、生理和免疫功能发育不完善,儿童肺炎起病急、来势猛、并发症多,易进展为重症肺炎。脓毒症是重症肺炎的主要并发症之一,约有1/3的患者可能出现 [1],发生脓毒性休克后患儿病死率可达40% [2]。重症肺炎合并脓毒性休克者因严重全身炎症反应、多器官功能障碍等因素导致血流动力学不稳,除积极抗感染治疗外,还需要进行液体治疗甚至应用血管活性药物以维持血流动力学稳定。目前儿童血流动力学治疗多依据心电、血氧、血压、尿量监测结合医师个人经验进行,特别是对危重症患者难以达到精准评估与治疗,已广泛应用于临床的PiCCO、Swan-Ganz漂浮导管等循环监测技术 [3],因其有创性在儿科的应用受到极大限制。近年来USCOM开始应用于儿科,已有多项研究表明,USCOM在儿童和新生儿心输出量的监测中与PiCCO及超声检查结果具有较好的一致性与可靠性 [4] [5] [6]。本研究利用USCOM监测重症肺炎合并脓毒性休克患儿心功能及外周循环状态的变化,探讨其对临床评估病情,并指导治疗的价值及意义。

2. 资料与方法

2.1. 研究对象

自2019年1月1日至2020年5月31日,青岛大学附属医院儿科重症医学科由门急诊收住院,诊断为重症肺炎合并脓毒性休克患儿。重症肺炎诊断标准 [7]:(1) 一般情况差;(2) 拒食或脱失征;(3) 意识障碍;(4) 呼吸频率明显增快(婴儿心率 > 70次/min,年长儿心率 > 50次/min);(5) 发绀;(6) 呼吸困难;(7) 多肺叶受累或≥2/3的肺;(8) 胸腔积液;(9) 脉搏血氧饱和度 ≤ 0.92;(10) 肺外并发症;存在以上任何一项的患儿可诊断为重症肺炎。脓毒性休克诊断参照儿童脓毒性休克(感染性休克)诊治专家共识(2015 版) [8]。排除标准:住院不足24小时者;持续进行心肺复苏者、死亡者;存在遗传性疾病或合并其他严重基础病者。本研究经青岛大学附属医院医学伦理委员会通过,并在遵循家属知情同意下开展。共57例患儿纳入本研究,其中男30例,女27例,行USCOM血流动力学监测患儿作为观察组,以同期未给予USCOM监测且资料完整患儿作为对照组。

2.2. 方法

2.2.1. 一般治疗

所有患儿按照《儿童社区获得性肺炎管理指南(2013修订)上》 [9] 及《儿童脓毒性休克(感染性休克)诊治专家共识(2015版)》 [8] 给予积极抗感染治疗,高流量鼻导管吸氧或面罩氧疗,保持气道通畅,液体复苏和维持输液,应用血管活性药物,控制血糖、镇痛、营养支持等常规治疗。观察组除常规治疗外还予USCOM监测血流动力学指标,根据USCOM监测结果调整治疗方案。

2.2.2. USCOM监测指标及意义

USCOM (Pty Ltd., CoifsHarbour, NSW, Australia)监测指标包括心率(Heart Rate, HR)、心脏指数(Cardiac Index, CI)、外周血管阻力指数(Systemic Vascular Resistance Index, SVRI)、校正射血时间(Flow Time Corrected, FTc)、每搏输出量指数(Stroke Volume Index, SVI)、肌力指数(Smith Madigan Inotro-py Index, SMII)。1~12月龄婴幼儿USCOM测得的心功能指标正常参考值如下:HR 103~145次/min,CI 3.7~5.1 L/min∙m2,SVRI 919~1464 d∙s∙cm−5∙m2,FTc 339~386 ms,SVI 31~40 ml/m2,SMII 1.08~1.40 W/m2 [10] [11] [12]。

2.2.3. 检查操作方法

所有操作者均接受USCOM操作培训且考核合格。USCOM仪器定期通电运行并检修,保证仪器性能稳定和监测结果准确。操作过程:(1) 输入患儿信息:性别、身高、体重、血压、血红蛋白值、血氧饱和度等。(2) 在患儿安静或镇静状态下,取平卧位,探头频率2.2 MHz,将探头放置胸骨上窝紧贴皮肤采集主动脉血流频谱,听取最响和最强的信号音,前后左右小幅度调整探头位置,选择最合适的位置,获得呈三角形、线条平滑、填充饱满、有尖锐顶点的多普勒血流频谱,每次测量持续约30 s,连续测量3次取平均值。

2.2.4. 治疗干预

重症肺炎合并脓毒性休克者休克类型主要表现为低排高阻或低排低阻。USCOM检查结果常表现为CI、SVI、SMII降低,SVRI、FTc升高或降低。检查结果低于正常参考值下限给予干预处理。液体复苏首次按20 ml/kg晶体液5~10分钟快速输注,再行USCOM评估,如症状无改善或CI值仍低,继续给予液体复苏,1 h内液体总量可达40~60 ml/kg。对液体治疗后仍存在低血压和低灌注者加用血管活性药:多巴胺3~5 μg/(kg∙min)。对照组根据症状、体征、心电氧合监测及血压指标调整输液量及血管活性药物用量,输液最大量1 h内40~60 ml/kg,多巴胺3~5 μg/(kg∙min)。观察组每次干预治疗后6小时内完成USCOM复测,若治疗仍需调整或继续,则干预后6小时内再行复测。

2.2.5. 统计学分析

用SPSS 22.0统计软件进行分析,计量资料用 x ¯ ± s表示,组间比较用独立样本t检验,计数资料用百分位%表示,组内比较使用配对t检验;计数资料比较用x2检验。以P < 0.05为差异有统计学意义。

3. 结果

3.1. 两组患儿治疗前一般情况比较

观察组29例,其中男16例,女13例,年龄(5.39 ± 2.39)个月,处于休克代偿期25例,失代偿期4例;对照组28例,其中男14例,女14例,年龄(5.50 ± 2.54)个月,处于休克代偿期25例,失代偿期3例;2组患儿性别、年龄差异及休克分期均无统计学意义(P > 0.05)。两组患儿治疗前心率、呼吸频率、小儿危重症评分、pH值、平均动脉压、C-反应蛋白水平及血培养阳性率比较差异无统计学意义(P > 0.05),见表1

Table 1. Comparison of the general information before treatment between the control group and the observation group ( x ¯ ± s)

表1. 对照组与观察组患儿治疗前一般情况比较( x ¯ ± s)

注:HR:心率;RR:呼吸频率;PCIS:小儿危重症评分法;MAP:平均动脉压;CRP:C-反应蛋白。

3.2. 观察组治疗前及治疗后USCOM监测指标变化

观察组29例给予液体复苏。治疗后HR、CI、SVRI、SVI、FTc、SMII较治疗前有显著改善,差异有统计学意义(P < 0.05),见表2。12例给予多巴胺治疗。治疗后HR、CI、SVRI、SVI、FTc、SMII较治疗前明显好转,差异有统计学意义(P < 0.05),见表3

Table 2. Comparison of the USCOM indicators of the liquid treatment cases in the observation group before and after treatment ( x ¯ ± s)

表2. 观察组液体复苏病例治疗前后USCOM监测指标变化( x ¯ ±s)

注:USCOM:无创超声心输出量监测仪;HR:心率;CI:心脏指数;SVRI:外周血管阻力指数;SVI:每搏输出量指数;FTc:校正射血时间;SMII:肌力指数。

Table 3. Comparison of the indicators of the USCOM dopamine treatment cases in the observation group before and after treatment ( x ¯ ± s)

表3. 观察组多巴胺治疗病例治疗前后USCOM监测指标变化( x ¯ ± s)

注:USCOM:无创超声心输出量监测仪;HR:心率;CI:心脏指数;SVRI:外周血管阻力指数; SVI:每搏输出量指数;FTc:校正射血时间;SMII:肌力指数。

3.3. 两组患儿复苏液体量及血管活性药物用量比较

观察组液体复苏29例,液体量(43.7 ± 8.33 ml/kg);对照组28例,液体量(54.59 ± 6.15 ml/kg)。观察组应用血管活性药物12例,多巴胺用量(47.2 ± 4.76 mg/kg);对照组15例,多巴胺用量(69.63 ± 7.45 mg/kg),观察组复苏液体入量及血管活性药物用量均少于对照组,差异有统计学意义(P < 0.05)。

3.4. 两组患儿并发症发生率、机械通气时间、转为非重症时间及PICU住院时间、 死亡病例数比较

观察组发生并发症1例(4.3%),为心力衰竭1例;观察组8例(33.3%),其中呼吸衰竭4例,心力衰竭3例,凝血功能异常1例;观察组机械通气时间及转为非重症时间均少于对照组,差异均有统计学意义(P < 0.05);两组PICU住院时间及死亡病例数差异无统计学意义(P > 0.05),见表4

Table 4. Comparison of the incidence of complications, mechanical ventilation time, into the non-severe cases time and duration of PICU stay, number of deaths between the control group and the observation group ( x ¯ ± s)

表4. 对照组与观察组并发症发生,机械通气、转为非重症及PICU住院时间、死亡病例数比较( x ¯ ± s)

注:转为非危重病例参考标准:PCIS > 80分。

4. 讨论

重症肺炎是PICU常见的一种儿童危重症,除呼吸系统受累,在病原体毒素侵袭、炎症介质作用下可引起心力衰竭、呼吸衰竭、SIRS,甚至脓毒症休克及MODS等严重并发症,在短时间内威胁生命,病死率高 [13]。重症肺炎合并脓毒性休克本质是在感染因素作用下肺部炎性渗出继而出现全身炎症反应,导致血流分布异常,器官功能障碍的微循环障碍,早期治疗重点不仅是积极抗感染及氧疗,增加心输出量,改善循环,纠正体内液体分布,保障重要脏器供血、供氧 [14],在休克早期液体复苏与心功能不全时加用正性肌力药物 [15],可以有效防止炎症反应和循环衰竭的发生和发展。因此,对重症肺炎合并脓毒性休克患儿早期进行血流动力学监测,对评估病情及指导诊疗具有重要意义。

本研究发现,病例普遍存在HR增快,FTc、CI、SVI降低,SVRI升高,血流动力学变化以低排高阻多见,根据脓毒性休克诊断标准,儿童脓毒性休克早期可无血压下降,仅有组织低灌注表现,本研究病例大多处于休克代偿期。观察组在USCOM指导下进行液体复苏,相较于对照组,观察组输液量更少,血管活性药物用量更少,差异均具有统计学意义。分析该结果原因为:观察组除根据临床指标评估复苏效果,还在给予液体复苏及血管活性药物应用后实时进行USCOM监测,若血流动力学指标尚未恢复正常但已明显好转,提示液体反应性良好,可根据监测结果精准调整液体入量;若血流动力学指标无好转,提示液体反应性欠佳,可及时加用血管活性药物以维持血压灌注,后期再根据监测结果调整血管活性药物的应用,使得观察组病情变化发现更为早期,能够更早的调整治疗方案,让治疗更加精准。对照组缺乏明确血流动力学指标的指导,仅依据血气、血压、尿量、精神反应等临床指标并不能准确评估患儿容量及液体反应性,往往复苏液体量更大,使用血管活性药物时间更长。但小儿心脏代偿功能较低,若补液量过多, 可增加患儿心脏负担,易引起急性心衰、肺水肿、急性肾损伤等严重并发症;若补液量不足,则难以纠正并维持患儿循环,影响患儿疗效。本研究中,对照组并发症发生率、机械通气时间均高于观察组,差异有统计学意义;两组PICU住院时间及病死率差异无统计学意义。但既往研究显示 [16],液体超负荷10%与病死率升高有关。这一点尚需大样本、多中心随机对照实验进行进一步研究。其次,USCOM监测指标明确了患儿血流动力学类型,可对休克患儿进行病理分型,从而在治疗中可以更精确的选择合适的血管活性药物;本研究中,观察组USCOM监测结果表明大多数处于休克早期或代偿期患儿经积极地液体复苏后复测血流动力学参数可较治疗前明显好转并趋于稳定。少部分患儿液体复苏反应不佳,应用血管活性药物后可见显著改善。国外研究显示 [17],儿童脓毒性休克多表现为低心输出量和高循环阻力,与患儿死亡直接相关的指标是低心输出量,早期液体复苏可显著降低患儿病死率,多数患儿对积极液体复苏反应良好。这与我们的研究结果是一致的。

USCOM通过超声测量流经主动脉瓣处血流速度及每次心脏搏动时的血流动力,获得患儿心脏功能及整体循环状态的指标 [18],实现连续监测心脏泵血功能及整体循环状态 [19]。在血流动力学监测中CI提示机体功能或基础代谢的变;SVI反映每博输出量的变化,是血流量和心肌收缩发生变化的信号;FTc代表前负荷,提示循环血容量;SVRI代表血流在循环中遇到的阻力,指导血管活性药物应用。相较于PiCCO、Swan-Ganz漂浮导管等传统有创监测方法,USCOM同样可获得准确、可靠的数据 [20],其准确性已在成人与儿童患者中进行了验证 [21] [22],平卧位是检查的最佳体位 [23],且具有可重复性高、持续监测等优点。尤其适于在婴幼儿等不宜采取有创监测的患者中应用。在操作方面,USCOM装置轻便,使用简洁,研究证实接受培训的临床医生可以迅速掌握USCOM监测技术,并且能得出可靠的血流动力学监测数据 [24]。

综上,USCOM具有简便、准确、快速等优点,有助于临床医师在第一时间掌握患儿血流动力学状态,评估心功能,能够精准地指导危重患儿的早期治疗,个体化指导液体管理及血管活性药物的合理应用,故USCOM监测对危重患儿病情评估及指导诊疗具有重要的临床应用价值。

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