Key messages
• Ultrasound guidance may lead to a higher first-attempt success rate and improved time to successful common femoral artery (CFA) access, while reducing the venipuncture rate (unintentionally accessing the vein instead of the targeted artery) and number of access attempts, compared to anatomic landmark guidance.
• Further research is needed to increase our confidence in the evidence.
What is the condition, and how is it treated?
Percutaneous (through the skin) common femoral artery (CFA) access is an essential step for various endovascular procedures (minimally invasive procedures that address issues within the arteries and/or veins), from diagnostic arterial angiograms (a type of picture taken to assess the inside of an artery and its potential disease) to therapeutic interventions (those used to treat conditions of the arteries), including, but not limited to, stenting (placement of a small device to maintain the openness of an artery), embolization (intentionally causing a clot to form to block off an unwanted portion of a blood vessel), and thromboembolectomy (removal of an unwanted clot from a blood vessel). These procedures make it possible to diagnose and treat occlusive arterial disease (blockages of the arteries) as well as aneurysms (bulge in the wall of an artery), dissections (tears in the wall of an artery), and arteriovenous fistulae (an abnormal connection between an artery and a vein). Traditionally, landmarks in the anatomy (anatomic landmarks) have been used to guide CFA access. More recently, ultrasound guidance has emerged as a possibly lower-risk and more effective option, although results of studies comparing ultrasound versus anatomic landmarks for guiding percutaneous CFA access have differed.
What did we want to find out?
We aimed to find out whether ultrasound guidance improves the rate and speed of successful CFA access, reduces the complication rate associated with percutaneous CFA access, and/or improves the patient's experience compared to anatomic landmark guidance for percutaneous CFA access.
What did we do?
We searched for studies comparing ultrasound guidance to anatomic landmark guidance using palpation (pressing the surface of the body with the fingers or hands) or fluoroscopy (X-ray guidance), or both, for obtaining percutaneous CFA access in people undergoing diagnostic or therapeutic endovascular procedures. We compared and summarized the results of the studies and rated our confidence in the evidence based on factors such as study methods and sizes.
What did we find?
We found nine studies enrolling 4447 participants. The studies suggest that ultrasound guidance may lead to a higher first-attempt success rate and improved time to successful CFA access, while reducing the venipuncture rate (unintentionally accessing the vein instead of the targeted artery) and number of access attempts, compared to anatomic landmark guidance.
What are the limitations of the evidence?
We have moderate to little confidence in the evidence because it is possible that people in the studies knew which treatment they were getting; some important outcomes could not be addressed due to limited evidence; and the studies failed to look at certain important patient populations, like those at high risk.
How up-to-date is this evidence?
The evidence is current to January 2024.
Ultrasound guidance may confer clinical benefit over anatomic landmark guidance for percutaneous CFA access regarding first-pass success, time to successful CFA access, and unintentional venipuncture, without increasing the risk of adverse events. Evidence for other outcomes including major bleeding, overall cannulation success, number of access attempts, retroperitoneal hematoma, minor bleeding, pseudoaneurysms, arterial dissection, arteriovenous fistulae, arterial occlusion, infection, or pain scores demonstrates no benefit to ultrasound guidance over anatomic landmark guidance. Data on higher-risk subgroups, including people with elevated BMI, extensive atherosclerosis or calcification, and high femoral artery bifurcation, are lacking. Generalizability was also limited by the high risk of bias across most studies and the exclusion of important subgroups (e.g. people with non-palpable pulses).
The use of percutaneous arterial access for endovascular procedures has broad applications, from diagnostic angiography in the coronary and peripheral arteries, to thromboembolectomy in people with ischemic stroke and percutaneous coronary intervention in those with acute myocardial infarction. The rise of these procedures worldwide underscores the importance of obtaining precise and timely arterial access while minimizing the risk of adverse events. Traditionally, anatomic landmarks, such as the anterior superior iliac spine and symphysis pubis, have guided percutaneous common femoral artery (CFA) access, along with manual palpation of the pulse and fluoroscopy to confirm bony landmarks. Anatomic landmarks can be deceptive, however, especially in certain subpopulations, such as those with a high femoral artery bifurcation, elevated body mass index (BMI), or non-palpable femoral pulses. Ultrasound has emerged as a promising tool to guide percutaneous CFA access, offering enhanced visualization and providing real-time guidance. Notwithstanding this theoretical advantage, trials have inconsistently demonstrated an advantage to ultrasound guidance over anatomic landmarks, and concerns surrounding added set-up time and training have limited its uptake both clinically and across society guidelines.
To assess the efficacy and safety of ultrasound compared to anatomic landmarks to guide percutaneous access of the CFA for the purpose of endovascular arterial imaging or treatment.
The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 25 January 2024.
We selected randomized controlled trials comparing ultrasound guidance to anatomic landmark guidance (using manual palpation or fluoroscopy, or both) for percutaneous CFA access in people undergoing endovascular therapy for diagnostic or therapeutic purposes.
We used standard Cochrane methods. Primary outcomes included first-pass success, time to successful CFA access, and major bleeding (including hematoma requiring transfusion, hematoma extending length of stay, hematoma ≥ 5 cm, unexplained hemoglobin drop, or major/severe bleeding as defined by each trial). Secondary outcomes included overall cannulation success, venipuncture, pain scores, number of access attempts, major complications (including retroperitoneal hematoma, pseudoaneurysms, dissections, arteriovenous fistulae, or occlusions), adverse events (including minor bleeding, infection, and neuropathy) up to 30 days, quality of life, re-intervention rate up to 30 days, and total number of access sites attempted. We conducted sensitivity analyses to determine whether the effect of ultrasound guidance on time to successful CFA access differed across studies that defined this endpoint differently, and to assess the impact of studies that permitted rescue ultrasound on study endpoints.
Of 1422 records identified through our search of the databases, nine randomized controlled trials enrolling 4447 participants fulfilled our inclusion criteria. All trials were at high risk of bias in at least one domain, with seven trials at overall high risk of bias and the remaining two at overall unclear risk of bias.
There may be increased first-pass success (odds ratio [OR] 3.35, 95% confidence interval [CI] 2.53 to 4.44; P < 0.001, I² = 69%; 7 trials, 4274 participants; low certainty evidence) and reduced time to successful CFA access (mean difference [MD] −17.24 s, 95% CI −27.04 to −7.43 s; P < 0.001, I² = 45%; 6 trials, 3570 participants; low certainty evidence) with ultrasound guidance compared to anatomic landmark guidance. Ultrasound guidance may also reduce unintentional venipuncture (OR 0.26, 95% CI 0.18 to 0.38; P < 0.001, I² = 33%; 7 trials, 4178 participants; low certainty evidence) and number of access attempts (MD −0.59, 95% CI −0.91 to −0.26; P < 0.001, I² = 96%; 5 trials, 3362 participants; very low certainty evidence), although the evidence for the latter outcome is very uncertain. Ultrasound guidance may have little to no effect on major bleeding (OR 0.60, 95% CI 0.32 to 1.13; P = 0.11, I² = 38%; 6 trials, 4016 participants; low certainty evidence), overall cannulation success (though the evidence is very uncertain) (OR 1.46, 95% CI 0.93 to 2.30; P = 0.10, I² = 59%; 4 trials, 2520 participants; very low certainty evidence), and likely has little to no effect on pain scores (MD 0.00, 95% CI −0.34 to 0.34; P = 1.00, I² not applicable; 1 trial, 939 participants; moderate certainty evidence). Ultrasound guidance may also have little to no effect on retroperitoneal hematoma, pseudoaneurysm formation, arterial dissection, arteriovenous fistulae, target vessel occlusion, minor bleeding, or infection compared to anatomic landmark guidance (P > 0.05 for all). Lack of data precluded an assessment of re-intervention rates, neuropathy, quality of life, or number of access sites.
Sensitivity analysis revealed that ultrasound guidance may reduce time to successful CFA access in studies that defined this outcome as time from administration of local anesthetic to successful sheath insertion (MD −23.65 s, 95% CI −34.28 to −13.01 s; 3 trials, 1517 participants), but not in studies that defined it as time from the first movement of the fluoroscopy table/application of the ultrasound probe to successful sheath insertion (MD −14.85 s, 95% CI −33.45 to 3.75 s; 2 trials, 1941 participants) or time from skin penetration by the access needle to sheath insertion (MD 11.00 s, 95% CI −43.06 to 65.06 s; 1 trial, 112 participants).
Sensitivity analysis excluding studies that permitted rescue ultrasound resulted in no change in the overall effect of ultrasound versus anatomic landmark guidance on any of the observed outcomes.