An interventional study of Crushed ice and Frozen peas in Temperature, Blood Flow Velocity and Radial Artery Size, sponsored by Julio Alberto Mateos Arroyo. Suspended at 1 site in Spain. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-08-22.
Sponsored by Julio Alberto Mateos Arroyo · Not applicable, Interventional, and Supportive care
Low-intervention clinical trial. The thermal and hemodynamic effects of different cryotherapy devices are evaluated. This study is included in the doctoral thesis of the principal investigator.
Investigators:
Principal Investigator: Julio Alberto Mateos Arroyo (RN, MSc, PhD student) Directors: Ignacio Zaragoza García (RN, PhD), Ismael Ortuño Soriano (RN, PhD), Paloma Posada Moreno (PhD).
Setting: Faculty of Nursing, Physiotherapy and Podiatry of the Universidad Complutense de Madrid.
The three interventions to be evaluated are:
Hypothesis: There are differences in the reduction of temperature, dimensions of the internal lumen of the radial artery and blood flow inside it depending on the different modalities of cryotherapy (crushed ice or bag of frozen peas) applied in the anatomical area of the wrist, point of arterial puncture for blood gas analysis.
Main objective: To analyze the effect of 3 cryotherapy devices on the radial artery area.
Secondary objectives
Design: Randomized controlled clinical trial. This is a crossover clinical trial in which all participants will receive all interventions and will be randomized in the order in which they receive them.
Population: Adults with a good general state of health, who specifically do not have factors that could affect their thermoregulation or vascular pathologies.
Main variables:
Pain caused by arterial puncture for blood gas analysis is one of the most common problems with this procedure. The low utilization rates of effective methods by healthcare providers for pain reduction, such as subcutaneous infiltration of anesthetics, make it necessary to search for effective and simple methods. The use of cryotherapy devices has proven effective for this purpose because the decrease in temperature increases pain threshold and tolerance due to a reduction in nerve conduction velocity and inhibition of nociceptors. In order to standardize these devices, it is necessary to understand the specific thermodynamic and hemodynamic effects of these devices. At the hemodynamic level, the reduction in temperature can produce arterial vasoconstriction. This effect may decrease the palpation of the radial artery, a necessary step for the identification of the optimal point of arterial puncture. Our hypothesis is that there are differences in temperature reduction, radial artery internal lumen dimensions and blood flow inside the radial artery depending on the different cryotherapy modalities applied in the anatomical area of the wrist, the point of arterial puncture for blood gas analysis. In order to obtain an answer to this hypothesis, we will propose a randomized controlled clinical trial with a sham comparator and two active interventions: crushed ice and frozen peas. In addition, this trial has a crossover design with the aim of minimizing the differences that may arise due to individual particularities (within-group variability), and thus increase the possible effect of the interventions (between-group variability). This choice has its justification in that the application of cryotherapy, according to some studies, has a thermal reducing effect with high individual variability. In this study, adults with a good general state of health, who specifically do not have factors that could affect their thermoregulation or vascular pathologies, will be recruited.
This is the only study on the registry with Julio Alberto Mateos Arroyo as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Each subject will receive all interventions and the control and they will randomly assigned to a sequence order. In this arm the sequence order is: crushed ice - frozen peas - control.
Device: Crushed ice · Device: Frozen peas · Device: Room temperature gel
Each subject will receive all interventions and the control and they will randomly assigned to a sequence order. In this arm the sequence order is: crushed ice - control - frozen peas.
Device: Crushed ice · Device: Frozen peas · Device: Room temperature gel
Each subject will receive all interventions and the control and they will randomly assigned to a sequence order. In this arm the sequence order is: frozen peas - crushed ice - control.
Device: Crushed ice · Device: Frozen peas · Device: Room temperature gel
Each subject will receive all interventions and the control and they will randomly assigned to a sequence order. In this arm the sequence order is: frozen peas - control - crushed ice.
Device: Crushed ice · Device: Frozen peas · Device: Room temperature gel
Each subject will receive all interventions and the control and they will randomly assigned to a sequence order. In this arm the sequence order is: control - crushed ice - frozen peas.
Device: Crushed ice · Device: Frozen peas · Device: Room temperature gel
Each subject will receive all interventions and the control and they will randomly assigned to a sequence order. In this arm the sequence order is: control - frozen peas - crushed ice.
Device: Crushed ice · Device: Frozen peas · Device: Room temperature gel
Each participant will receive two active devices and one sham comparator in a crossover design.The cryotherapy device used consists of an opaque bag with a plastic outer cover and an aluminum interior filled with 80 grams of crushed ice. This device is applied on the skin where the optimal palpation point of the radial artery is located, where arterial puncture for blood gas analysis is usually performed to reduce skin temperature in ranges that decrease nerve conduction velocity and increase pain threshold.
Also known as: ih1
Each participant will receive two active devices and one sham comparator in a crossover design. The cryotherapy device used consists of an opaque bag with a plastic outer cover and an aluminum interior filled with 80 grams of frozen peas. This device is applied on the skin where the optimal palpation point of the radial artery is located, where arterial puncture for blood gas analysis is usually performed to reduce skin temperature in ranges that decrease nerve conduction velocity and increase pain threshold.
Also known as: ig2
Each participant will receive two active devices and one sham comparator in a crossover design. The sham comparator device used consists of an opaque bag with an external plastic cover and an aluminum interior filled with 80 grams of ultrasound gel at room temperature. This device is applied on the skin where the optimal palpation point of the radial artery is located, where arterial puncture for blood gas analysis is usually performed.
Also known as: ctrl
Skin temperature
Surface temperature measurements will be taken at different times since the application of the interventions. The thermal camera FLIR TG267 will be used, temperature range: -25ºC to 380ºC, sensitivity \<70ºC mK, resolution 160 X 120.
Time frame: Prior to application of the intervention
Skin temperature
Surface temperature measurements will be taken at different times since the application of the interventions. The thermal camera FLIR TG267 will be used, temperature range: -25ºC to 380ºC, sensitivity \<70ºC mK, resolution 160 X 120.
Time frame: After 5 minutes from the application of the intervention
Skin temperature
Surface temperature measurements will be taken at different times since the application of the interventions. The thermal camera FLIR TG267 will be used, temperature range: -25ºC to 380ºC, sensitivity \<70ºC mK, resolution 160 X 120.
Time frame: After 10 minutes from the application of the intervention
Skin temperature
Surface temperature measurements will be taken at different times since the application of the interventions. The thermal camera FLIR TG267 will be used, temperature range: -25ºC to 380ºC, sensitivity \<70ºC mK, resolution 160 X 120.
Time frame: After 15 minutes from the application of the intervention
Skin temperature
Surface temperature measurements will be taken at different times since the application of the interventions. The thermal camera FLIR TG267 will be used, temperature range: -25ºC to 380ºC, sensitivity \<70ºC mK, resolution 160 X 120.
Time frame: After 20 minutes from the application of the intervention
Change in radial artery size
Three measurements of the anteroposterior diameter of the radial artery will be taken in the same place and plane to ensure reliability at each time point studied. Samsung HS50 ultrasound scanner with a 3-14 Hz linear probe will be used for the measurement.
Time frame: 0-20 minutes
Change in radial artery blood flow
To obtain the blood flow of the radial artery, color Doppler mode will be used to correctly identify the vessel and then the pulsed Doppler mode will be used to obtain the peak systolic low (PSV), that is, the maximum systolic velocity (VSM). Three consecutive PSV measurements will be obtained in the same place and plane to ensure reliability at each time point studied. Samsung HS50 ultrasound scanner with a 3-14 Hz linear probe will be used for the measurement.
Time frame: 0-20 minutes
Discomfort
The discomfort generated by the interventions and the comparator will be recorded 5, 10, 15 and 20 minutes after their application. An ad hoc likert-type numerical scale will be used, where 1 means no discomfort and 10 means extreme discomfort.
Time frame: After 5 minutes from the application of the intervention
Discomfort
The discomfort generated by the interventions and the comparator will be recorded 5, 10, 15 and 20 minutes after their application. An ad hoc likert-type numerical scale will be used, where 1 means no discomfort and 10 means extreme discomfort.
Time frame: After 10 minutes from the application of the intervention
Discomfort
The discomfort generated by the interventions and the comparator will be recorded 5, 10, 15 and 20 minutes after their application. An ad hoc likert-type numerical scale will be used, where 1 means no discomfort and 10 means extreme discomfort.
Time frame: After 15 minutes from the application of the intervention
Discomfort
The discomfort generated by the interventions and the comparator will be recorded 5, 10, 15 and 20 minutes after their application. An ad hoc likert-type numerical scale will be used, where 1 means no discomfort and 10 means extreme discomfort.
Time frame: After 20 minutes from the application of the intervention
Adverse events
Number of participants with adverse events
Time frame: Through study completion, an average of 3 months
This study is suspended, as verified in Aug 2025. You cannot join it, but the record below documents what was studied.
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