McCarthy Melissa L, Shokoohi Hamid, Boniface Keith S, Eggelton Russell, Lowey Andrew, Lim Kelvin, Shesser Robert, Li Ximin, Zeger Scott L
Department of Health Policy and Management, George Washington University Hospital, Washington, DC; Department of Emergency Medicine, George Washington University Hospital, Washington, DC.
Department of Emergency Medicine, George Washington University Hospital, Washington, DC.
Ann Emerg Med. 2016 Jul;68(1):10-8. doi: 10.1016/j.annemergmed.2015.09.009. Epub 2015 Oct 23.
Randomized controlled trials report inconsistent findings when comparing the initial success rate of peripheral intravenous cannulation using landmark versus ultrasonography for patients with difficult venous access. We sought to determine which method is superior for patients with varying levels of intravenous access difficulty.
We conducted a 2-group, parallel, randomized, controlled trial and randomly allocated 1,189 adult emergency department (ED) patients to landmark or ultrasonography, stratified by difficulty of access and operator. ED technicians performed the peripheral intravenous cannulations. Before randomization, technicians classified subjects as difficult, moderately difficult, or easy access according to visible or palpable veins and perception of difficulty with a landmark approach. If the first attempt failed, we randomized subjects a second time. We compared the initial and second-attempt success rates by procedural approach and difficulty of intravenous access, using a generalized linear mixed regression model, adjusted for operator.
The 33 participating technicians enrolled a median of 26 subjects (interquartile range 9 to 55). The initial success rate was 81% but varied significantly by technique and difficulty of access. The initial success rate by ultrasonography was higher than landmark for patients with difficult access (48.0 more successes per 100 tries; 95% confidence interval [CI] 35.6 to 60.3) or moderately difficult access (10. 2 more successes per 100 tries; 95% CI 1.7 to 18.7). Among patients with easy access, landmark yielded a higher success rate (10.6 more successes per 100 tries; 95% CI 5.8 to 15.4). The pattern of second-attempt success rates was similar.
Ultrasonographic peripheral intravenous cannulation is advantageous among patients with difficult or moderately difficult intravenous access but is disadvantageous among patients anticipated to have easy access.
在比较使用体表标志法与超声引导法对静脉穿刺困难患者进行外周静脉置管的初始成功率时，随机对照试验报告的结果并不一致。我们试图确定对于静脉穿刺难度不同的患者，哪种方法更具优势。
我们进行了一项两组平行随机对照试验，将1189例成年急诊科患者随机分为体表标志法组或超声引导法组，按穿刺难度和操作人员进行分层。急诊科技术人员进行外周静脉置管操作。在随机分组前，技术人员根据可见或可触及的静脉以及体表标志法的穿刺难度感知，将受试者分为穿刺困难、中度困难或容易三类。如果首次尝试失败，我们对受试者进行第二次随机分组。我们使用广义线性混合回归模型，比较了不同操作方法和静脉穿刺难度下的首次和第二次尝试成功率，并对操作人员进行了校正。
33名参与研究的技术人员纳入的受试者中位数为26例（四分位间距9至55例）。初始成功率为81%，但因技术和穿刺难度的不同而有显著差异。对于穿刺困难的患者，超声引导法的初始成功率高于体表标志法（每100次尝试多成功48.0例；95%置信区间[CI]35.6至60.3）；对于穿刺中度困难的患者，超声引导法的初始成功率也高于体表标志法（每100次尝试多成功10.2例；95%CI1.7至18.7）。在穿刺容易的患者中，体表标志法的成功率更高（每100次尝试多成功10.6例；95%CI5.8至15.4）。第二次尝试成功率的模式相似。
超声引导外周静脉置管对于静脉穿刺困难或中度困难的患者具有优势，但对于预计穿刺容易的患者则具有劣势。
