Skin Warming for Blood Loss

Overseen By James Pearson, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Colorado, Colorado Springs

Must not be taking: Cardiovascular, Pulmonary, Renal, CNS

Disqualifiers: Pregnancy, Cardiac, Respiratory, Neurological, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 5

Duration: 4 visits

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how warming the skin affects blood pressure and how the body manages simulated blood loss after exercising in the cold. The main focus is on skin surface rewarming, a method of externally warming the body, and its impact on blood flow and tolerance to blood loss. Ideal participants are healthy individuals not taking medications that affect the heart or lungs and who have normal blood pressure levels.

As an unphased trial, this study allows participants to contribute to innovative research that could enhance understanding of body temperature regulation and cardiovascular health.

Will I have to stop taking my current medications?

Yes, you will need to stop taking any medications that affect the heart, lungs, kidneys, or brain, as these are not allowed in the trial.

What prior data suggests that skin surface rewarming is safe for use during simulated blood loss?

Research has shown that warming the skin is generally safe. Studies have found that applying heat to the skin can help prevent issues caused by low body temperatures. Patients usually tolerate this method well. Reports from past studies indicate very few side effects. When used during surgery, skin warming even slightly reduced blood loss. Overall, its safe use in many situations supports its safety for new trials like this one. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about using skin surface rewarming for managing blood loss because it offers a novel way to stabilize patients without relying on traditional blood transfusion methods. Unlike current treatments, which often involve invasive procedures or medications, this approach uses controlled warming of the skin to potentially improve blood circulation and prevent shock after blood loss. By adjusting skin temperature, this method might enhance the body's natural response to blood loss, providing a non-invasive and easily applicable solution. This could be especially beneficial in emergency situations or environments where access to standard treatments is limited.

What evidence suggests that skin surface rewarming is effective for blood loss?

Research has shown that warming the skin can help prevent problems caused by low body temperature. Forced-air warming systems, which heat the body through the skin, have proven especially effective. For instance, one study found that these systems greatly reduced major heart-related issues. Additionally, using a forced-air warming system was the best method to warm elderly patients after surgery. In this trial, participants will experience different levels of skin warming after exercise in the cold to assess its impact on blood pressure stability and the body's response to simulated blood loss. These findings suggest that warming the skin might help maintain stable blood pressure and improve the body's handling of blood loss, especially after exercising in the cold. ^{1 2 3 4 6}

Who Is on the Research Team?

James Pearson, PhD

Principal Investigator

Univeristy of Colorado Colorado Springs

Are You a Good Fit for This Trial?

This trial is for healthy adults aged 18-40 with normal blood pressure, who speak English and have no known diseases. Smokers, pregnant or breastfeeding individuals, those on certain medications, with physical limitations, a history of appendectomy or weighing less than 80 pounds cannot participate.

Inclusion Criteria

Diastolic blood pressure <90 mmHg

Systolic blood pressure <140mmHg

I do not have any known diseases or illnesses.

Exclusion Criteria

Current use of tobacco or nicotine products

Currently pregnant or breast feeding

I have had my appendix removed.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Initial Assessment

Initial study visit to examine exercise capacity

1 day

1 visit (in-person)

Treatment

Participants undergo four trials with varying skin temperatures after exercise in a cold environment to assess arterial blood pressure and tolerance to simulated blood loss

4 visits

4 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Skin Surface Rewarming

Trial Overview

The study tests how skin warming affects blood pressure and tolerance to simulated blood loss after being in the cold and exercising. It involves rewarming the skin's surface using various methods while undergoing lower body negative pressure.

How Is the Trial Designed?

Group I: Skin Temperature Control During Simulated Blood Loss After Exercise Cold Stress Experimental Treatment 4 Interventions

After exercise in the cold and participants skin will remain cold (\~82°F), be returned to normal (\~90°F), be slightly warmed (\~93°F) or heated (\~95°F) sixty seconds after the onset of LBNP.

Who Is Running the Clinical Trial?

University of Colorado, Colorado Springs

Lead Sponsor

Trials

20

Recruited

5,500+

Published Research Related to This Trial

Preoperative warming combined with intraoperative skin-surface warming significantly maintained higher core temperatures in patients during the first two hours of anesthesia compared to those who were only warmed during surgery.

Patients who received both preoperative and intraoperative warming experienced no shivering and were more likely to be extubated early, highlighting the effectiveness of this warming strategy in preventing hypothermia and improving recovery conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preoperative combined with intraoperative skin-surface warming avoids hypothermia caused by general anesthesia and surgery. Vanni, SM., Braz, JR., Módolo, NS., et al.[2022]

Active body surface warming (ABSW) systems effectively maintain normothermia during and after noncardiac surgeries, significantly reducing the risk of wound infections and shivering, while also increasing patient satisfaction.

However, ABSW does not appear to influence postoperative pain levels or opioid consumption, indicating that while it helps with temperature regulation and some complications, it may not directly impact pain management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Perioperative Active Body Surface Warming Systems on Analgesic and Clinical Outcomes: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Balki, I., Khan, JS., Staibano, P., et al.[2023]

Maintaining normothermia during surgery is crucial to prevent complications like increased blood loss, cardiac issues, and wound infections, highlighting the importance of effective temperature management.

Forced-air warming devices are recommended for preventing hypothermia, but their safe use requires proper device selection, patient assessment, and staff education on hypothermia risks and warming technology.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The safe and efficient use of forced-air warming systems. Wu, X.[2013]

The BARRIER EasyWarm blanket significantly improved mean perioperative core body temperature in 246 adult patients undergoing elective surgery, with an average temperature of 36.5°C compared to 36.3°C for standard blankets (P<.001).

Using the BARRIER EasyWarm blanket reduced the incidence of inadvertent perioperative hypothermia from 60% to 38% intraoperatively and from 49% to 24% postoperatively, while also enhancing patient thermal comfort without serious adverse effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Active perioperative patient warming using a self-warming blanket (BARRIER EasyWarm) is superior to passive thermal insulation: a multinational, multicenter, randomized trial. Torossian, A., Van Gerven, E., Geertsen, K., et al.[2017]

In a study of 35 patients undergoing total knee arthroplasty, those using conductive fabric warming (HotDog® system) maintained significantly higher temperatures during surgery compared to those using forced-air warming combined with a water mattress.

Both warming methods achieved 100% normothermia by the end of surgery, indicating that while both methods are effective, conductive fabric warming may provide better temperature maintenance during the preoperative period.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Normothermia is Best Achieved by Warming Above and Below with Pre-warming Adjunct: A Comparison of Conductive Fabric Versus Forced-air and Water. Ohki, K., Kawano, R., Yoshida, M., et al.[2019]

In a study of 28 patients undergoing extensive thoracoabdominal surgeries, those using a forced air warming system maintained their body temperature effectively, with a mean temperature of 36.9°C after three hours of surgery.

In contrast, patients relying on passive heat preservation techniques experienced a significant drop in temperature to 35.1°C, highlighting the efficacy of forced air warming in preventing perioperative hypothermia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Forced air warming and intraoperative hypothermia. Lindwall, R., Svensson, H., Söderström, S., et al.[2014]

Using a fluid warming and forced-air warming system during surgery significantly maintained patients' core temperature (36.4°C) compared to the control group (35.3°C), which is crucial for patient safety and recovery.

The warming intervention also led to a shorter extubation time (18 minutes) and eliminated postoperative shivering, demonstrating its efficacy in improving recovery outcomes for patients undergoing elective abdominal surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[The effect of intraoperative warming on patient core temperature]. Xu, L., Zhao, J., Huang, YG., et al.[2006]

Skin surface warming (SSW) is more effective than intravenous fluid warming (IFW) in preventing hypothermia and maintaining acid-base balance in elderly patients undergoing abdominal surgery under general anesthesia, based on a study of 60 patients.

While SSW helped prevent decreases in bicarbonate levels and base excess, it did not maintain normal body temperature post-surgery, indicating that while SSW is beneficial, it may not fully address temperature regulation in this patient group.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[A comparison of the effects of intravenous fluid warming and skin surface warming on peri-operative body temperature and acid base balance of elderly patients with abdominal surgery]. Park, H., Yoon, H.[2019]

In a study of 47 patients recovering from hypothermic cardiopulmonary bypass, forced-air warming significantly reduced the incidence, duration, and severity of shivering compared to traditional warmed cotton blankets.

Forced-air warming effectively increased skin surface temperatures without causing excessive central temperature elevation, indicating it is a safer and more effective rewarming method post-surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effects of forced-air warming on postbypass central and skin temperatures and shivering activity. Mort, TC., Rintel, TD., Altman, F.[2019]

In a study of 200 patients undergoing surgery, pre-operative skin-surface warming significantly reduced the incidence of hypothermia, with only 6% of patients becoming hypothermic after 30 minutes of pre-warming compared to 69% in the non-pre-warmed group.

Pre-warming for just 10 or 20 minutes was effective in preventing hypothermia and also reduced postoperative shivering, indicating that even short durations of warming can have substantial benefits for patients undergoing general anesthesia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of short time periods of pre-operative warming in the prevention of peri-operative hypothermia. Horn, EP., Bein, B., Böhm, R., et al.[2012]

Citations

1.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC8687605/

Active body surface warming systems for preventing ...

We reviewed the effects of warming the body by transferring heat through the skin surface to prevent complications caused by unintended low body temperature ( ...

2.

pubmed.ncbi.nlm.nih.gov

pubmed.ncbi.nlm.nih.gov/27098439/

Active body surface warming systems for preventing ...

Only one study at low risk of bias observed a beneficial effect with forced-air warming on major cardiovascular complications (RR 0.22, 95% CI ...

3.

journals.lww.com

journals.lww.com/md-journal/fulltext/2019/05310/effect_of_forced_air_warming_system_in_prevention.80.aspx

Effect of forced-air warming system in prevention of...

The use of a forced-air warming system set at 42°C was shown to be the most effective way of rewarming elderly patients with postoperative hypothermia.

4.

clinicaltrials.gov

clinicaltrials.gov/study/NCT06597214

Intraoperative Warming: Comparison of Two Temperature ...

The study aims to determine whether the warmUP system is as effective as the Bair Hugger® in maintaining core body temperature. The main questions this trial ...

5.

cochranelibrary.com

cochranelibrary.com/cdsr/doi/10.1002/14651858.CD009016.pub2/full

Active body surface warming systems for preventing ...

We reviewed the effects of warming the body by transferring heat through the skin surface to prevent complications caused by unintended low body ...

6.

sciencedirect.com

sciencedirect.com/science/article/pii/S2049080121010098

Prevention and management of perioperative hypothermia ...

The aim of this systematic review is to develop a clear clinical practice protocol in prevention and management of perioperative hypothermia for elective adult ...