The CAlcium and VAsopressin following Injury Early Resuscitation trial, or simply CAVALIER, is a research study that will look at whether giving calcium, vasopressin, or both early in the course of treatment would help severely injured patients that lose a lot of blood survive their injuries.

Normally when a person loses a lot of blood, they may receive calcium, vasopressin, or both as part of standard medical care, but not until they arrive at the hospital or are admitted to an intensive care unit (ICU). After a patient is determined to be sick enough to enroll in the study, researchers will do a randomization (like flipping a coin) to determine if the patient will receive a study drug or a placebo (salt water).



Click here to complete a survey about CAVALIER.

For this study, some people who have injuries that caused them to lose a lot of blood will get calcium before arriving at the hospital, vasopressin before going to the ICU, and some people will get both. The other people will get a placebo. A placebo is not a drug but is designed to look like a drug to help compare with the study drugs to learn if the study drug as any real effect. Information from health records for all groups will also be collected as part of the study. Researchers will look at both groups of people and see if one group did better than the other.

The study is “double blinded” which means the study drug and placebo the care team will look identical to remove any bias against the drug. If something were to happen where the care team needs to know which was given, a plan is in place to give them that information quickly. For this study, researchers will compare these groups to see if one group recovers from their injuries better than the other. Additionally, researchers will compare the group of patients who received both calcium and vasopressin to see if they recover better.


Who will be included?

CAVALIER will enroll adults who are over 18 years old and less than 90 years old who are:

  • Severely injured patients that lose a lot of blood (at risk of hemorrhagic shock)
  • Being transported to or undergoing emergency surgery at a research site participating in CAVALIER.

Where is this research happening?

CAVALIER is being done at hospitals across the United States. Subjects enrolled at participating hospitals may be included in the prehospital phase (calcium or placebo), in-hospital phase (vasopressin or placebo), or both.

Subjects enrolled at Zuckerberg San Francisco General Hospital will only be enrolled in the in-hospital (vasopressin or placebo) phase.

To see the LITES sites in your region and which projects they are working on, including CAVALIER, please see the map.

Why this research?

Trauma is the leading cause of death and researchers think that providing two commonly used products earlier than typical care as adjuncts to blood products could improve chances of survival.

Why Calcium?

Why Vasopressin?

Patients who lose a lot of blood are often given blood or blood components. Patients who receive blood or blood components also receive calcium later in their care, which helps their blood to clot.

Researchers think that giving calcium sooner may be better at lowering the risk of death.

When   patients lose a lot of blood their blood pressure drops. Drugs called “vasopressors” or “pressors” are given to patients with low blood pressure to “squeeze” their veins to increase blood pressure to a healthy level.

Researchers think giving vasopressin early could improve the chances of recovery in patients who have sustained life threatening injuries with loss of blood.

What are the risks? Are there any benefits?

Patients who have lost a lot of blood often receive calcium, vasopressin, or both. Researchers believe that giving these drugs closer to the time of injury has similar risks to when they are given now.  The research could provide information that saves lives.


How are people enrolled in the study?

People who have traumatic injuries and lose a lot of blood (at risk of hemorrhagic shock) who are being transported to a research site participating in CAVALIER and patients who are also undergoing emergent surgery for their injuries may be included in this study.

Normally, researchers must ask a person for their consent before they can be in a study. Because traumatic injuries must be treated right away, there may not be time to get consent. Giving consent for medical research usually means reading information, talking with doctors and nurses, and having time to think about whether to join. A person with traumatic injury is often not able to do these things. Sometimes researchers can talk to the patient’s family to ask for consent. However, in the emergency of traumatic injury, the family is often not around or can’t be found before the injured person must be treated. This study could not be done without special permission to include people before getting consent. This permission is called Exception from Informed Consent, or EFIC. Once the enrolled person is better and can consent or their family arrives at the hospital, the researchers will ask for consent to continue with the study. For more information regarding EFIC, please visit this page.


How do I opt out of the study?

You can opt-out of the study by contacting us using any of the methods below and letting us know that you do not want to participate. Please make sure to give us your name and contact information so that we can get in touch with you. We can provide you with a hypoallergenic silicone bracelet to wear that indicates that you should not be enrolled into the study. Please note that opting out of the study only means that you will not receive calcium or vasopressin as part of the study. Opting out will not prevent you from getting these products as part of your normal care.



For questions or to learn more about this study, please call us at 1-800-664-0557 or email us at