Distributive ShockNCT07653659
Hemodynamic Effects of Norepinephrine Reduction on Critical Closing Pressure in Distributive Shock
An observational study of Distributive Shock and Hemodynamic Assessment, run by Peking Union Medical College Hospital at 1 site in China.
Trial summary
This study prospectively observes changes in critical closing pressure (Pcc) and derived hemodynamic parameters in mechanically ventilated distributive shock patients when clinically indicated norepinephrine dose reduction is performed by the attending physician. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Distributive Shock, Hemodynamic Assessment, Critical Illness
- What is being tested?
- Not applicable- observational study
- How many people
- 30 participants
- Where
- 1 siteChina
- Study dates
- 1 Sep 2025to 1 Sep 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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: Adult distributive shock patients receiving invasive mechanical ventilation and norepinephrine treatment
Who may be able to join
- Adult distributive shock patients aged ≥18 years;
- Receiving norepinephrine infusion with MAP in the 75-85 mmHg range;
- PiCCO catheter in situ;
- Under mechanical ventilation;
- Clinically indicated norepinephrine dose reduction per attending physician judgment.
Who cannot join
- Significant cardiac arrhythmia affecting CO measurement reliability;
- Contraindication to airway plateau pressure maneuver;
- Active titration of other vasoactive agents within 30 minutes prior to measurement;
- Hemodynamic instability making it impossible to reduce norepinephrine dose.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Peking Union Medical College Hospital
Beijing, Beijing Municipality, 100730
Bin Du, 86-15136289398, sunyaliii@163.com
About this study
Official title: Changes in Critical Closing Pressure and Derived Hemodynamic Parameters Following Norepinephrine Dose Reduction in Distributive Shock Patients: a Prospective Observational Study
This study prospectively observes changes in critical closing pressure (Pcc) and derived hemodynamic parameters in mechanically ventilated distributive shock patients when clinically indicated norepinephrine dose reduction is performed by the attending physician. Pcc is measured before and 30 minutes after dose reduction using a stepwise inspiratory hold maneuver via PiCCO monitoring.
Read the detailed description
In distributive shock patients receiving norepinephrine with MAP maintained in the 75-85 mmHg range, attending physicians may reduce norepinephrine dose based on clinical judgment. This study observes hemodynamic changes associated with such reductions without any investigator-initiated intervention. Critical closing pressure (Pcc) and derived parameters including tissue perfusion pressure (TPP), mean systemic filling pressure analogue (Pmsf), and vascular waterfall (VW) are measured at baseline and 30 minutes after dose reduction, provided MAP variability is less than 5 mmHg. Pcc is derived from linear regression of simultaneously measured cardiac output (CO) and mean arterial pressure (MAP) during stepwise inspiratory hold maneuvers. Steady-state CO and MAP values are recorded during the final 3 seconds of 12-second inspiratory holds at plateau pressures of 5, 15, 25, and 35 cmH2O. The x-intercept of the CO-MAP regression line is taken as Pcc.
- Conditions
- Distributive Shock, Hemodynamic Assessment, Critical Illness
- Being tested
- Not applicable- observational study
- Keywords
- Critical closing pressure, Tissue perfusion pressure, Vascular waterfall, Norepinephrine dose, Distributive shock
- Medical subject headings
- Critical Illness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Not applicable- observational studyOther
Observation of hemodynamic parameters before and after clinically indicated norepinephrine dose reduction. No investigator-initiated intervention was performed.
| Study group | Role | What they receive |
|---|---|---|
| Distributive shock patients undergoing norepinephrine dose reduction | Mechanically ventilated distributive shock patients in whom the attending physician clinically indicated norepinephrine dose reduction, with MAP transitioning from the 75-85 mmHg range to the 65-75 mmHg range. Receives: Other: Not applicable- observational study |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in critical closing pressure (Pcc, Unit: mmHg) before and after norepinephrine dose reduction
Pcc is derived from linear regression of simultaneously measured cardiac output against mean arterial pressure during stepwise inspiratory hold maneuvers via PiCCO monitoring. The x-intercept of the regression line (at zero flow) represents Pcc. Measurement is performed at baseline and 30 minutes after norepinephrine dose reduction.
Measured: Baseline and 30 minutes after norepinephrine dose reduction
Change in tissue perfusion pressure (TPP, unit: mmHg) before and after norepinephrine dose reduction
TPP is calculated as the difference between mean arterial pressure (MAP) and critical closing pressure (Pcc): TPP = MAP minus Pcc, unit: mmHg
Measured: Baseline and 30 minutes after norepinephrine dose reduction
Secondary outcomes (3)
Change in mean systemic filling pressure analogue (Pmsf, unit: mmHg) before and after norepinephrine dose reduction
Pmsf is estimated as the x-intercept of the linear regression of cardiac output against central venous pressure (CVP), representing the venous pressure at zero flow.
Measured: Baseline and 30 minutes after norepinephrine dose reduction
Change in Vascular waterfall (VW, unit: mmHg) before and after norepinephrine dose reduction
Vascular waterfall (VW) is calculated as Pcc minus Pmsf.
Measured: Baseline and 30 minutes after norepinephrine dose reduction
Change in capillary refill time (CRT, unit: seconds）
Capillary refill time is assessed by applying pressure to the fingertip for 5 seconds and measuring the time for color to return after release.
Measured: Baseline and 30 minutes after norepinephrine dose reduction
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Jun 2026
- Study start1 Sep 2025
- Primary completion1 Jul 2027 (estimated)
- Study completion1 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Distributive ShockStudies of the same condition, open and under way.
- More trials run by Peking Union Medical College HospitalThe 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
- Cohort
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Peking Union Medical College Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Bin Du, Peking Union Medical College Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07653659
- Sponsor's protocol ID
- pumch-micu202606
- Status last verified
- Jun 2026
- First submitted
- 8 Jun 2026
- Last updated
- 17 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Changes in Critical Closing Pressure and Derived Hemodynamic Parameters Following Norepinephrine Dose Reduction in Distributive Shock Patients: a Prospective Observational Study
- ClinicalTrials.gov ID
- NCT07653659
- Acronym / sponsor ID
- pumch-micu202606
- Conditions
- Distributive Shock, Hemodynamic Assessment, Critical Illness
- Keywords
- Critical closing pressure, Tissue perfusion pressure, Vascular waterfall, Norepinephrine dose, Distributive shock
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Peking Union Medical College HospitalUniversity, hospital or other
- Study start
- 1 Sep 2025 (actual)
- Primary completion
- 1 Jul 2027 (estimated)
- Study completion
- 1 Sep 2027 (estimated)
- First posted
- 17 Jun 2026 (actual)
- 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.
This study prospectively observes changes in critical closing pressure (Pcc) and derived hemodynamic parameters in mechanically ventilated distributive shock patients when clinically indicated norepinephrine dose reduction is performed by the attending physician. Pcc is measured before and 30 minutes after dose reduction using a stepwise inspiratory hold maneuver via PiCCO monitoring.
Detailed description
In distributive shock patients receiving norepinephrine with MAP maintained in the 75-85 mmHg range, attending physicians may reduce norepinephrine dose based on clinical judgment. This study observes hemodynamic changes associated with such reductions without any investigator-initiated intervention. Critical closing pressure (Pcc) and derived parameters including tissue perfusion pressure (TPP), mean systemic filling pressure analogue (Pmsf), and vascular waterfall (VW) are measured at baseline and 30 minutes after dose reduction, provided MAP variability is less than 5 mmHg. Pcc is derived from linear regression of simultaneously measured cardiac output (CO) and mean arterial pressure (MAP) during stepwise inspiratory hold maneuvers. Steady-state CO and MAP values are recorded during the final 3 seconds of 12-second inspiratory holds at plateau pressures of 5, 15, 25, and 35 cmH2O. The x-intercept of the CO-MAP regression line is taken as Pcc.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Distributive shock patients undergoing norepinephrine dose reduction | – | Other: Not applicable- observational studyMechanically ventilated distributive shock patients in whom the attending physician clinically indicated norepinephrine dose reduction, with MAP transitioning from the 75-85 mmHg range to the 65-75 mmHg range. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult distributive shock patients receiving invasive mechanical ventilation and norepinephrine treatment
Key inclusion criteria (5 listed)
- Adult distributive shock patients aged ≥18 years;
- Receiving norepinephrine infusion with MAP in the 75-85 mmHg range;
- PiCCO catheter in situ;
- Under mechanical ventilation;
- Clinically indicated norepinephrine dose reduction per attending physician judgment.
Key exclusion criteria (4 listed)
- Significant cardiac arrhythmia affecting CO measurement reliability;
- Contraindication to airway plateau pressure maneuver;
- Active titration of other vasoactive agents within 30 minutes prior to measurement;
- Hemodynamic instability making it impossible to reduce norepinephrine dose.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Not applicable- observational studyObservation of hemodynamic parameters before and after clinically indicated norepinephrine dose reduction. No investigator-initiated intervention was performed. | Other | Distributive shock patients undergoing norepinephrine dose reduction |
Primary outcome
Change in critical closing pressure (Pcc, Unit: mmHg) before and after norepinephrine dose reduction
Time frame: Baseline and 30 minutes after norepinephrine dose reduction
Pcc is derived from linear regression of simultaneously measured cardiac output against mean arterial pressure during stepwise inspiratory hold maneuvers via PiCCO monitoring. The x-intercept of the regression line (at zero flow) represents Pcc. Measurement is performed at baseline and 30 minutes after norepinephrine dose reduction.
Change in tissue perfusion pressure (TPP, unit: mmHg) before and after norepinephrine dose reduction
Time frame: Baseline and 30 minutes after norepinephrine dose reduction
TPP is calculated as the difference between mean arterial pressure (MAP) and critical closing pressure (Pcc): TPP = MAP minus Pcc, unit: mmHg
3 secondary outcomes
Change in mean systemic filling pressure analogue (Pmsf, unit: mmHg) before and after norepinephrine dose reduction
Time frame: Baseline and 30 minutes after norepinephrine dose reduction
Change in Vascular waterfall (VW, unit: mmHg) before and after norepinephrine dose reduction
Time frame: Baseline and 30 minutes after norepinephrine dose reduction
Change in capillary refill time (CRT, unit: seconds）
Time frame: Baseline and 30 minutes after norepinephrine dose reduction
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Jun 2026.
- Individual participant dataSharing planned: No
Related trials for Distributive Shock
RecruitingObservational study
Angiotensin II Stress Test. Renin Kinetics During Treatment of Vasoplegic Shock With Angiotensin II.
Shock, Vasoplegic Syndrome
RecruitingPhase 3
Efficacy and Safety of Angiotensin II Injection Versus Placebo in Patients With Refractory Distributed Shock
Vasodilatory Shock
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.
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 Distributive Shock and Hemodynamic Assessment, run by Peking Union Medical College Hospital at 1 site in China.
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 5 inclusion and 4 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: looking for participants now, as of the sponsor's last update on 17 Jun 2026. 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 China. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Bin Du, Dr (86+15136289398, sunyaliii@163.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in critical closing pressure (Pcc, Unit: mmHg) before and after norepinephrine dose reduction (time frame: Baseline and 30 minutes after norepinephrine dose reduction). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 17 Jun 2026.