A Study of the Relationship between Recruitment Maneuvers and Blood Volume Status in Critically Ill Patients


  • Study type

  • Study IDs

  • Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • Site IRB
    • Rochester, Minnesota: 14-007423
    Sponsor Protocol Number: 14-007423

About this study

The purpose of this pilot study is to see if recruitment maneuvers performed during ICU care in patients who have a breathing tube are useful in assessing a blood volume status based on changes in their blood pressure during the recruitment maneuver. The recruitment maneuver consists of increasing the pressure of the breath given through the breathing tube, and is commonly done as a standard part of ICU care for patients who are connected to a machine that helps them breathe. Results will be compared to ultrasound measurements of the main vein of the body (inferior vena cava) which serve as a non-invasive standard of care technique.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria

Inclusion Criteria:

  1. Mechanically-ventilated patients admitted to the trauma-surgical ICU (Mary Brigh 7 B/G)  with a clinical diagnosis of hypovolemic or distributive shock, who are undergoing active resuscitation by the ICU team members,
  2. Blood pressure monitoring via arterial line
  3. Arterial line systolic blood pressure ≥90
  4. Age ≥ 18

Exclusion Criteria: 

  1. Patients who are not mechanically ventilated
  2. Patients who do not have an arterial line at time of enrollment
  3. Patients with abdominal dressings which prevent the use of ultrasonography in the epigastrium
  4. Pregnant patients
  5. Patients <18 years of age
  6. Prisoners/Incarcerated individuals
  7. Recent pneumonectomy
  8. Occult pneumothorax (i.e. pneumothorax only visible on chest CT without clinical symptoms)
  9. Patients with angulated, displaced rib fractures with associated pneumothorax and no thoracostomy tube in place at the time of enrollment.
  10. Patients with difficult to control elevated intracranial pressure
  11. Patients with history of emphysematous bleb and spontaneous pneumothorax.
  12. Patients with a tube thoracostomy and active air leak.
  13. Recently placed internal mammary grafts.

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Erica Loomis, M.D.

Closed for enrollment

Contact information:

Amy Headlee CCRP



More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

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