JVA ISSN 1129-7298
J Vasc Access 2015; 16 (4): 321-326 DOI: 10.5301/jva.5000346
ORIGINAL ARTICLE
Ultrasound-guided peripheral venous access: a meta-analysis and systematic review Lori A. Stolz1, Uwe Stolz1, Carol Howe2, Isaac J. Farrell1, Srikar Adhikari1 1 2
Department of Emergency Medicine, University of Arizona Medical Center, Tucson, AZ - USA Information Services, Arizona Health Sciences Library, University of Arizona, Tucson, AZ - USA
ABSTRACT Objectives: The objective of this study was to determine through a systematic review of the literature and metaanalysis whether success rates, time to cannulation, and number of punctures required for peripheral venous access are improved with ultrasound guidance compared with traditional techniques in patients with difficult peripheral venous access. Methods: We conducted a systematic search of MEDLINE, Web of Science, The Cochrane Library, ClinicalTrials. gov, Cumulative Index to Nursing, and Allied Health Literature. Studies were included if they met the following criteria: patients of any age identified as having difficult peripheral venous access; real-time ultrasound guidance was used for peripheral venous cannulation; and inclusion of at least one of these outcomes (success rates, time to successful cannulation and number of punctures required). Results: Seven studies were selected for final analysis. Ultrasound guidance improved success rates when compared with traditional techniques [pooled odds ratio (OR) 3.96; 95% confidence interval (95% CI) 1.75-8.94]. No significant difference between ultrasound-guided techniques and traditional techniques was detected for time to cannulation or number of punctures required. Conclusions: In patients with difficult peripheral venous access, ultrasound guidance increased success rates of peripheral venous placement when compared with traditional techniques. However, ultrasound guidance had no effect on time to successful cannulation or number of punctures required for successful cannulation. Keywords: Cannulation, Peripheral venous access, Ultrasound
Introduction Peripheral venous access is essential for emergency care, for the delivery of life-saving medications, fluids, and laboratory analysis. Obtaining necessary peripheral venous access is difficult in approximately 35% of patients who present to the emergency department (1). With multiple failed attempts at peripheral venous access placement, patients experience pain, suffer delays in their care, and are also at risk for infection (2). In circumstances in which no peripheral venous access is possible, central venous access is often the alternative (3). Central venous lines have enormous risks, including infection, arterial puncture, bleeding, thrombosis, pneumothorax, hemothorax, air embolism, and catheter misplacement. Reducing central Accepted: December 7, 2014 Published online: February 4, 2015 Corresponding author: Srikar Adhikari, MD, MS Department of Emergency Medicine University of Arizona Medical Center P.O. Box 245057 Tucson, AZ 85724-5057, USA
[email protected] © 2015 Wichtig Publishing
line associated bacterial infections has become a priority of several governmental agencies, healthcare providers, insurers, and regulators due to the increased cost and morbidity associated with central lines (4, 5). The insertion of central lines due to poor peripheral venous access without other appropriate indications poses an unnecessary risk for the patient. One alternative to traditional landmark-driven, palpation, or blind techniques of placing peripheral venous lines is using ultrasound guidance for placement. Several studies have been published evaluating the efficacy of ultrasound-guided peripheral venous access, with some finding a benefit and others no benefit, compared with traditional techniques (6-12). The objective of this study was to determine through a systematic review of the literature and meta-analysis whether success rates, time to cannulation, and number of punctures required for peripheral venous access are improved with ultrasound guidance compared with traditional techniques in patients with difficult peripheral venous access.
Methods Study design A systematic review protocol was created to specifically address the study question. The protocol was reviewed and
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agreed upon by all co-investigators a priori. This study was approved as exempt by the institutional review board. Search strategy The following databases were selected for search: MEDLINE, Web of Science, The Cochrane Library, ClinicalTrials.gov, Cumulative Index to Nursing, and Allied Health Literature. A basic web search was also performed. The search strategy was designed by a medical librarian [CH] with experience in systematic reviews and the searches were conducted with the assistance of the librarian. No limits were used in any database search. All languages, ages, providers, and patient settings were included. The search was conducted in November 2012 and was not otherwise limited by date. Search terms included ultrasonography, sonography, intravenous, catheter, vein, venous access, intravenous lines, intravenous (IV) insertion, cannulation, and several variations of these words. Cited references from all selected articles were reviewed for any additional studies. Study selection Specific inclusion and exclusion criteria were chosen a priori to accurately answer the study question and minimize bias in the selection process. Studies were included in this metaanalysis if they met the following criteria: patients of any age identified as having difficult peripheral venous access; realtime ultrasound guidance was used for peripheral venous cannulation; and inclusion of at least one of these outcomes (success rates of peripheral venous placement, time to successful cannulation, and number of punctures required for successful cannulation). The definition of difficult peripheral venous access is variable throughout the literature. For the purposes of this analysis, minimum criteria were defined as a patient history of difficult peripheral venous access or a minimum of two failed traditional palpation or landmarkbased attempts. Peripheral venous access was defined as placement in a peripheral vein, a catheter length not exceeding 9 cm, and termination of the catheter in a peripheral vein. Literature was screened by title or abstract review by two independent reviewers [LS, IF]. Discrepancies were reviewed by a third party [US]. Full-text articles were assessed for eligibility by two independent reviewers [LS, IF] with discrepancies reviewed by a third party [US]. Chosen articles were assessed for study quality by LS and IF. Studies with risk of bias that was deemed to be serious were excluded. Outcome measures The primary outcome measure was success rate of peripheral venous placement. The secondary outcomes were time to successful cannulation and number of punctures. Data analysis Data were abstracted from reports using standardized forms by two extractors [US, LS]. Data were then compared and disagreements were discussed by abstractors and reviewed by a third party [IF].
Fig. 1 - A meta-analysis flow chart for study selection.
We used random effects models using the method of DerSimonian and Laird, with estimates of heterogeneity taken from the Mantel-Haenszel model (13) to estimate the pooled odds ratio (OR) for success, weighted mean difference for number of punctures, and time to cannulation. Forest plots were used to present results for each outcome. Funnel plots were used to look for evidence of publication bias. All analyses were done using Stata v.12.1 (StataCorp, College Station, Texas, USA) using the “metan” module.
Results After database review, removal of duplicates, title and abstract review, and full article review, seven studies were identified for final analysis (Fig. 1 and Tab. I) (6-12). These included six peer-reviewed publications and one peer-reviewed abstract. One governmental publication was excluded due to high risk of bias due to failure to use intention-to-treat analysis, failure to meet a priori power analysis, and lack of peerreview (14). The pooled random effects OR for ultrasound-guided peripheral venous access success versus traditional technique peripheral venous success was 3.96 [95% confidence interval (95% CI) 1.75-8.94), indicating that ultrasound-guided peripheral venous access was successful more frequently than traditional methods (Fig. 2). The heterogeneity Chi-squared p-value was 0.12; however, the overall I-squared (proportion of results attributable to heterogeneity] was 41% and the between-study variance Tau-squared equal to 0.465. The funnel plot showed no obvious asymmetry (Fig. 3). One study was identified as a potential outlier (9). Sensitivity analysis excluding this study gave a pooled random effects © 2015 Wichtig Publishing
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TABLE I - Characteristics of studies included in meta-analysis Study design
Location
Operator
Age group
Ultrasound-guided cannulation technique
Aponte 2007 (6)
RCT
Surgical suite
Nurse anesthetist
Adults
Transverse
Benkandra 2012 (7)
RCT
Surgical suite
Physician
