US Guidance for Radial Arterial Puncture in Shock

Ultrasound Guidance Versus Conventional Technique for Radial Arterial Puncture in Patients With Shock in the Emergency Department: A Randomized Controlled Trial

Doctors in the emergency department often need to take blood samples from an artery to understand how well a patient is breathing and how the body is responding to serious illness. This is usually done by inserting a needle into an artery at the wrist. In patients with shock, this procedure can be difficult because blood pressure is low and the pulse may be hard to feel.

In this study, two different methods for obtaining arterial blood samples were compared in adult patients presenting to the emergency department with shock. In one group, the radial artery puncture was performed with ultrasound guidance, allowing direct visualization of the artery. In the other group, the procedure was carried out using the conventional palpation technique based on manual detection of the pulse.

Patients were randomly assigned to one of the two techniques. The study assessed the success of the procedure on the first attempt, the total number of attempts required, the time needed to obtain a successful sample, and whether puncture of the femoral artery was required when radial access could not be achieved.

The aim of the study was to evaluate whether the use of ultrasound improves the efficiency and success of radial artery blood sampling in patients with shock treated in the emergency department.

Study Overview

• Status: Completed
• Conditions: Shock; Shock Circulatory
• Intervention / Treatment: Procedure: Ultrasound-guided radial arterial puncture for arterial blood gas sampling; Procedure: Conventional radial artery puncture for arterial blood gas sampling

• Study Type: Interventional
• Enrollment (Actual): 100
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Antalya
    • Alanya, Antalya, Turkey (Türkiye), 07400
      • Alanya Alaaddin Keykubat University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients aged 18 years and older
• Patients diagnosed with shock
• Patients with an indication for arterial blood gas analysis due to respiratory or metabolic disorders
• Patients who provided written informed consent, either personally or through their legal representatives.

Exclusion Criteria:

• Patients who declined to participate
• Patients presenting with cardiac arrest
• Patients with a positive Allen test
• Patients with a history of coagulopathy
• Patients with evidence of infection at the puncture site
• Patients with evidence of trauma at the puncture site
• Patients with an arteriovenous fistula at the puncture site

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ultrasound-Guided Radial Artery Puncture; Participants undergo radial artery puncture for arterial blood gas sampling using real-time ultrasound guidance.	Procedure: Ultrasound-guided radial arterial puncture for arterial blood gas sampling; Radial artery puncture for arterial blood gas sampling performed under real-time ultrasound guidance. The artery is visualized on the screen and the needle is advanced under direct visualization until arterial blood flow is obtained.
Experimental: Conventional Palpation-Guided Radial Artery Puncture; Participants undergo radial artery puncture for arterial blood gas sampling using the conventional palpation technique, which represents the standard practice.	Procedure: Conventional radial artery puncture for arterial blood gas sampling; Radial artery puncture for arterial blood gas sampling performed using the conventional palpation technique. The artery is identified by manual palpation and the needle is advanced until arterial blood flow is obtained.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
First-Attempt Success of Radial Artery Puncture	In the ultrasound-guided group, a stopwatch was started when the ultrasound transducer made contact with the skin over the radial artery. The artery was visualized on the screen, and the needle was advanced under real-time ultrasound guidance until arterial blood flow was obtained. The stopwatch was stopped when arterial blood flow was observed in the syringe, and the procedure was considered successful. Each new puncture attempt was recorded as a separate attempt. In the conventional palpation group, a stopwatch was started when the physician made skin contact after identifying the radial artery by palpation. The needle was advanced into the radial artery until arterial blood flow was obtained. The stopwatch was stopped when arterial blood flow was observed in the syringe, and the procedure was considered successful. Each new puncture attempt was recorded as a separate attempt.	During procedure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The Number of Attempts	Secondary outcomes included the number of attempts until successful puncture, time to successful puncture, and the need for a rescue femoral artery puncture.	During procedure

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Procedure-Related Complications	Occurrence of any procedure-related complications during or following radial artery puncture.	within the emergency department stay (up to 4 hours after procedure)

Collaborators and Investigators

• Sponsor: Ismail Erkan Aydin

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2024
• Primary Completion (Actual): March 31, 2025
• Study Completion (Actual): March 31, 2025

Study Registration Dates

• First Submitted: January 9, 2026
• First Submitted That Met QC Criteria: January 15, 2026
• First Posted (Actual): January 23, 2026

Study Record Updates

• Last Update Posted (Actual): January 23, 2026
• Last Update Submitted That Met QC Criteria: January 15, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Ultrasound; Shock; Emergency department; Arterial blood gas; Radial artery puncture
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Pathological Conditions, Signs and Symptoms; Emergencies; Shock
• Other Study ID Numbers: September 11, 2024 ID: 20-09

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data related to the primary and secondary outcomes will be shared upon reasonable request to the corresponding author.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No