The New Position of Radial Artery Puncture and Cannulation of the Patient with Surgery（RAPC-02）

Invasive arterial blood pressure monitoring is the gold standard for blood pressure monitoring. The radial artery is the most commonly used site of arterial puncture and catheterization. The traditional puncture site is located at 0-1.9cm above the second wrist transverse crease. Due to the large range of motion of the wrist joint, the ductus arteriosus bending, unstable blood pressure waveform, and puncture complications occur. We believe that changing the puncture site is beneficial to enhance the stability of the perioperative arterial catheter, improve the accuracy of blood pressure values, and reduce the puncture-related complications. The purpose of this randomized controlled trial is to study the effect of radial artery puncture 2-4cm above the second wrist transverse crease on perioperative arterial catheter stability, blood pressure numerical accuracy, puncture-related indicators, and complications, using the traditional radial artery puncture site as a control.

Invasive arterial blood pressure monitoring is the gold standard for blood pressure monitoring. Arterial catheter instability is a common problem in the process of Invasive arterial blood pressure monitoring, such as catheter bending or prolapse, catheter blockage, and the low level of arterial waveform or even disappear. This is an important factor affecting the accuracy of implantation artery blood pressure monitoring, and also poses a great threat to the medical safety of patients in the perioperative period. The replacement of catheter also increases the workload of medical staff and the burden of patients. The purpose of this randomized controlled trial is to study the effect of radial artery puncture 2-4cm above the second wrist transverse crease on perioperative arterial catheter stability, blood pressure numerical accuracy, puncture-related indicators, and complications, using the traditional radial artery puncture site as a control.

This study is a single-center, prospective, randomized controlled trial. The sample size was calculated by superiority test: (1) according to the results of a previous retrospective study of the research group, the incidence of instability in the control group was 22%; (2) Set the optimal efficacy boundary Δ to -4.4%, the actual efficacy boundary Δ to -10%, with α = 0.025 and 1 - β = 0.90; (3) the loss of subjects was 5%, and the sample size of 1956 cases should be included in the Anesthesia Surgery Center of the Sixth Affiliated Hospital of Sun Yat-sen University.

Patients will receive written and verbal information about the trial before written consent is obtained. The subjects will be then randomized into the trial group and the control group. The puncture point of the test group is located 2-4cm above the second wrist transverse crease, and the puncture point of the control group is located at 0-1.9cm above the second wrist transverse crease.The randomization is performed using concealed allocation where envelopes are prepared externally using a randomization list prepared by a statistician.

Under ultrasound guidance, the patient will be undergone the radial artery puncture and cannulation by a highly senior resident with at least 3 years of puncture experience. Fast flush tests are performed and non-invasive arterial BP versus arterial BP values are recorded at 30-minute intervals after successful puncture.The occurrence of catheter instability are recorded until the end of the procedure.Patients are followed up within 24h, 48h and 72h after catheter removal to observe any post-puncture complications on the arterial puncture side.

Eligibility Criteria:
Inclusion Criteria:

* (1) Patients scheduled for elective surgery who, based on the clinical judgment of the physician, require invasive arterial pressure monitoring via the radial artery or repeated arterial blood gas analysis during the surgery; (2) Patients in the supine position during the surgery; (3) Patients with an American Society of Anesthesiologists (ASA) physical status classification of I-III; (4) Patients aged 18-75 years.

Exclusion Criteria:

* (1) Patients with a negative modified Allen's test; (2) Patients with a history of radial artery puncture within the past 3 months, or with infection or trauma at or near the puncture site; (3) Patients with coagulation disorders or a hypercoagulable state; (4) Patients receiving anticoagulant therapy; (5) Patients with concomitant vascular diseases, such as vasculitis; (6) Patients undergoing a surgical procedure involving the same anatomical region; (7) Patients with pre-existing hemodynamic instability, including those already receiving vasoactive medications and those with atrial fibrillation, atrial flutter, second-degree or higher atrioventricular block, multifocal premature ventricular contractions, or R-on-T premature ventricular contractions.