Decompression SicknessNCT01587209
Microparticles in Scuba Divers With Decompression Sickness
An observational study of Decompression Sickness and Dysbarism, run by University of Pennsylvania at 1 site in United States.
Trial summary
The investigators hypothesize that membrane microparticles (MPs) are liberated into the blood stream in response to decompression stress and that certain MPs characteristics initiate inflammatory responses that contribute to the clinical syndrome the investigators call decompression sickness. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Decompression Sickness, Dysbarism
- How many people
- 1 participants
- Where
- 1 siteUnited States
- Study dates
- Aug 2011to Sep 2014
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: SCUBA divers over age 21 that present for evaluation of suspected decompression sickness
Who may be able to join
- Patients who are given the diagnosis of decompression sickness will be offered entry into this study
Who cannot join
- Inability to provide informed consent
Trial locations and contacts
1 site in 1 country.
United States1 site
University of Pennsylvania
Philadelphia, Pennsylvania, 19104-6068
About this study
Official title: Phase 1 Study Investigating Alterations of Circulating Microparticles in Scuba Divers With Decompression Sickness
The investigators hypothesize that membrane microparticles (MPs) are liberated into the blood stream in response to decompression stress and that certain MPs characteristics initiate inflammatory responses that contribute to the clinical syndrome the investigators call decompression sickness. The research goal is to evaluate the number, type and time-course for elevations in MPs in sport SCUBA divers who present for treatment of decompression sickness. Blood samples are to be taken from consenting patients before and after they undergo treatment for decompression sickness and at a follow-up clinic visit from 1 to 3 weeks later (three samples total).
Read the detailed description
Microparticles (MPs) are small membrane bound vesicles shed from the surface of a variety of cells by what appear to be well regulated processes. They are elevated in many physiological and disease states and in some instances have been associated with organ injury. Shear stress - as can be caused by intravascular bubbles - is one of the stimuli known to cause cells to release microparticles. Most sport SCUBA dives have been shown to generate intravascular bubbles - even safe dives well within limits established by the US Navy and sports authorities. The investigators have reported elevations in several sub-types of MPs in a group of individuals undergoing a well monitored series of open-water SCUBA dives. There is no information of the occurrence of MPs in injured divers. The investigators have published results using a murine model which demonstrated that mice subjected to varying decompression stresses exhibit progressive elevations in circulating MPs derived from leukocytes, erythrocytes, platelets and endothelial cells. Using novel interventions the investigators demonstrated that MPs cause intravascular neutrophil activation and inflammatory perivascular injuries. Therefore, there is pathophysiological information to suggest that one or more element of MPs (number and/or pro-inflammatory subtype) may be proximal elements that precipitate the clinical syndrome the investigators call decompression sickness.
- Conditions
- Decompression Sickness, Dysbarism
- Keywords
- decompression, intravascular bubbles, neutrophil activation
- Medical subject headings
- Decompression Sickness, Barotrauma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Divers with decompression sickness | The sole group under study is SCUBA divers who have sustained decompression sickness |
What is being measured
The primary outcome is the main question the study is designed to answer.
Microparticle elevations in injured divers
We will quantify microparticles in plasma by standard flow cytometry techniques.
Measured: four years
Secondary outcomes (2)
Microparticle sub-types in injured divers
We will evaluate sub-types of microparticles to determine their cells of origin.
Measured: four years
Neutrophil activation in injured divers
We will evaluate presence of neutrophil activation in injured divers.
Measured: four years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Apr 2012 (estimated)
- Study startAug 2011
- Primary completionSep 2014
- Study completionSep 2014
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (3)Papers the sponsor has linked to this study.
- Other trials for Decompression SicknessStudies of the same condition, open and under way.
- More trials run by University of PennsylvaniaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case only
- Time perspective
- Prospective
- Enrolment
- 1 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Pennsylvania
- Sponsor type
- University, hospital or other
- Collaborators
- Office of Naval Research (ONR), University of Maryland
- Responsible party
- Sponsor
- Investigators
- Stephen R Thom, MD,PhD, Principal investigator, University of Pennsylvania
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01587209
- Sponsor's protocol ID
- 814139
- Status last verified
- Aug 2016
- First submitted
- 23 Apr 2012
- Last updated
- 22 Aug 2016
- Results posted
- No
- Data monitoring committee
- No
Publications
Thom SR, Yang M, Bhopale VM, Huang S, Milovanova TN. Microparticles initiate decompression-induced neutrophil activation and subsequent vascular injuries. J Appl Physiol (1985). 2011 Feb;110(2):340-51. doi: 10.1152/japplphysiol.00811.2010. Epub 2010 Oct 21.
PubMed 20966192Yang M, Milovanova TN, Bogush M, Uzun G, Bhopale VM, Thom SR. Microparticle enlargement and altered surface proteins after air decompression are associated with inflammatory vascular injuries. J Appl Physiol (1985). 2012 Jan;112(1):204-11. doi: 10.1152/japplphysiol.00953.2011. Epub 2011 Sep 29.
PubMed 21960660Thom SR, Milovanova TN, Bogush M, Bhopale VM, Yang M, Bushmann K, Pollock NW, Ljubkovic M, Denoble P, Dujic Z. Microparticle production, neutrophil activation, and intravascular bubbles following open-water SCUBA diving. J Appl Physiol (1985). 2012 Apr;112(8):1268-78. doi: 10.1152/japplphysiol.01305.2011. Epub 2012 Feb 9.
PubMed 22323646
Study at a glance
From the registry record, last updated by the sponsor on 22 Aug 2016. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phase 1 Study Investigating Alterations of Circulating Microparticles in Scuba Divers With Decompression Sickness
- ClinicalTrials.gov ID
- NCT01587209
- Acronym / sponsor ID
- 814139
- Conditions
- Decompression Sickness, Dysbarism
- Keywords
- decompression, intravascular bubbles, neutrophil activation
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 1 participants (actual)
- Lead sponsor
- University of PennsylvaniaUniversity, hospital or other
- Collaborators
- Office of Naval Research (ONR), University of Maryland
- Study start
- Aug 2011
- Primary completion
- Sep 2014 (actual)
- Study completion
- Sep 2014 (actual)
- First posted
- 30 Apr 2012 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The investigators hypothesize that membrane microparticles (MPs) are liberated into the blood stream in response to decompression stress and that certain MPs characteristics initiate inflammatory responses that contribute to the clinical syndrome the investigators call decompression sickness. The research goal is to evaluate the number, type and time-course for elevations in MPs in sport SCUBA divers who present for treatment of decompression sickness. Blood samples are to be taken from consenting patients before and after they undergo treatment for decompression sickness and at a follow-up clinic visit from 1 to 3 weeks later (three samples total).
Detailed description
Microparticles (MPs) are small membrane bound vesicles shed from the surface of a variety of cells by what appear to be well regulated processes. They are elevated in many physiological and disease states and in some instances have been associated with organ injury. Shear stress - as can be caused by intravascular bubbles - is one of the stimuli known to cause cells to release microparticles. Most sport SCUBA dives have been shown to generate intravascular bubbles - even safe dives well within limits established by the US Navy and sports authorities. The investigators have reported elevations in several sub-types of MPs in a group of individuals undergoing a well monitored series of open-water SCUBA dives. There is no information of the occurrence of MPs in injured divers. The investigators have published results using a murine model which demonstrated that mice subjected to varying decompression stresses exhibit progressive elevations in circulating MPs derived from leukocytes, erythrocytes, platelets and endothelial cells. Using novel interventions the investigators demonstrated that MPs cause intravascular neutrophil activation and inflammatory perivascular injuries. Therefore, there is pathophysiological information to suggest that one or more element of MPs (number and/or pro-inflammatory subtype) may be proximal elements that precipitate the clinical syndrome the investigators call decompression sickness.
Study design
- Observational model
- Case only
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Divers with decompression sickness | – | –The sole group under study is SCUBA divers who have sustained decompression sickness |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- SCUBA divers over age 21 that present for evaluation of suspected decompression sickness
Key inclusion criteria (1 listed)
- Patients who are given the diagnosis of decompression sickness will be offered entry into this study
Key exclusion criteria (1 listed)
- Inability to provide informed consent
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Microparticle elevations in injured divers
Time frame: four years
We will quantify microparticles in plasma by standard flow cytometry techniques.
2 secondary outcomes
Microparticle sub-types in injured divers
Time frame: four years
Neutrophil activation in injured divers
Time frame: four years
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Aug 2016.
- Background: PubMed 20966192Thom SR, Yang M, Bhopale VM, Huang S, Milovanova TN. Microparticles initiate decompression-induced neutrophil activation and subsequent vascular injuries. J Appl Physiol (1985). 2011 Feb;110(2):340-51. doi: 10.1152/japplphysiol.00811.2010. Epub 2010 Oct 21.
- Background: PubMed 21960660Yang M, Milovanova TN, Bogush M, Uzun G, Bhopale VM, Thom SR. Microparticle enlargement and altered surface proteins after air decompression are associated with inflammatory vascular injuries. J Appl Physiol (1985). 2012 Jan;112(1):204-11. doi: 10.1152/japplphysiol.00953.2011. Epub 2011 Sep 29.
- Background: PubMed 22323646Thom SR, Milovanova TN, Bogush M, Bhopale VM, Yang M, Bushmann K, Pollock NW, Ljubkovic M, Denoble P, Dujic Z. Microparticle production, neutrophil activation, and intravascular bubbles following open-water SCUBA diving. J Appl Physiol (1985). 2012 Apr;112(8):1268-78. doi: 10.1152/japplphysiol.01305.2011. Epub 2012 Feb 9.
Related trials for Decompression Sickness
Recruiting
Evaluating Potential Risk of Choking by Laryngeal Ultrasound in Patients With Acute Stroke
Acute Stroke
Recruiting
Comparing Pre-adaptation of In-stock Mesh Over In-house 3D Patient Specific Model to Reconstruct Unilateral Primary Orbital Fracture With and Without Intraoperative Navigation vs Conventional Intraoperative Free-hand Mesh Bending
Orbital Fractures, Unilateral
Recruiting
NASA Exercise Prebreathe Study
Decompression Sickness
Not yet recruitingObservational study
Health, Fitness, and Safety Knowledge as Determinants of Adverse Events in Recreational Divers in Poland
Decompression Sickness, Barotrauma
Not yet recruiting
Virtual Surgical Planning and Preoperative Plate Bending for Maxillofacial Fractures
Mandibular Fractures, Maxillofacial Injuries
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Stephen R Thom, MD,PhD principal investigator
University of Pennsylvania
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Decompression Sickness and Dysbarism, run by University of Pennsylvania at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 22 Aug 2016. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Microparticle elevations in injured divers (time frame: four years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01587209, which also lists 3 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 Aug 2016.