Physiological and clinical significance of mean circulatory and mean systemic filling pressure
Bibliographic record
Abstract
A pressure distends blood vessels even when the heart is not beating and there is no blood flow. This is called mean circulatory filling pressure (MCFP). We will first discuss why it is physiologically necessary to have this base pressure. Although all pressures in the vasculature are the same when there is no flow, blood volume distributes based on the compliance of the walls in each compartment. The compliance of systemic venous compartment is by far the largest and contain most of the blood volume. When flow starts, volume redistributes among the vascular regions based on the compliance and resistance draining them. Because of it dominates the total compliance, pressure in the systemic venous compartment changes very little; it is called mean systemic filling pressure (MSFP). Under normal hemodynamic conditions, differences between MCFP and MSFP are trivial because venous compliance is so large compared to all other vascular regions. When cardiac function is maximal, MCFP determines the maximum possible cardiac output. MSFP is significant for two reasons. It is the upstream pressure driving blood back to the right heart. Importantly, it also is the downstream pressure for systemic capillary drainage. Thus, a high MSFP increases the risk of tissue edema. From our review of the studies, the pressure difference from MSFP to the right atrium (RAP) is generally in the 3 to 6 mmHg range so that MSFP can be approximated by adding values in this range to properly measured RAP. Ideally, MSFP should be less than 10 mmHg to limit capillary drainage.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".