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

10 Participants Needed

Trial Summary

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 data supports the effectiveness of the treatment Skin Surface Rewarming, Active Body Surface Warming, Forced-Air Warming, Preanesthetic Skin-Surface Warming?

Research shows that preoperative and intraoperative skin-surface warming can effectively prevent hypothermia (abnormally low body temperature) during surgery, which can reduce complications like shivering and improve recovery conditions. Studies indicate that warming methods, including forced-air warming, help maintain normal body temperature, which is crucial for minimizing blood loss and ensuring patient safety during operations. ^{1 2 3 4 5}

Is skin warming generally safe for humans?

Skin warming methods like forced-air warming and self-warming blankets are generally considered safe when used correctly. They help maintain normal body temperature during surgery, reducing risks like increased blood loss and infections. Proper use includes choosing the right device, protecting against burns, and following manufacturer guidelines. ^{2 6 7 8 9}

How does skin warming differ from other treatments for blood loss?

Skin warming is unique because it involves using heat applied to the skin to maintain body temperature, which can help reduce blood loss during surgery. Unlike other treatments that might focus on medications or surgical techniques, this method uses forced-air warming systems to prevent hypothermia (abnormally low body temperature) and shivering, which can indirectly affect blood loss. ^{1 2 3 6 10}

What is the purpose of this trial?

Assess the effect of skin rewarming during lower body negative pressure upon arterial blood pressure and tolerance to simulated blood loss after exercise in the cold.

Research Team

James Pearson, PhD

Principal Investigator

Univeristy of Colorado Colorado Springs

Eligibility Criteria

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

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

Treatment Details

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.

Participant Groups

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+

Findings from Research

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 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]

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]

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]

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]

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 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]

References

1. United States 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. [2019]

2. England pubmed.ncbi.nlm.nih.gov

The effect of short time periods of pre-operative warming in the prevention of peri-operative hypothermia. [2012]

3. China pubmed.ncbi.nlm.nih.gov

[The effect of intraoperative warming on patient core temperature]. [2006]

4. Korea (South) 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]. [2019]

5. United States pubmed.ncbi.nlm.nih.gov

Preoperative combined with intraoperative skin-surface warming avoids hypothermia caused by general anesthesia and surgery. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

The effects of forced-air warming on postbypass central and skin temperatures and shivering activity. [2019]

7. United States 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. [2023]

8. United States pubmed.ncbi.nlm.nih.gov

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

9. United States 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. [2017]

10. England pubmed.ncbi.nlm.nih.gov

Forced air warming and intraoperative hypothermia. [2014]