This paper introduces Directional Pressure Failure (DPF) as a systems-level model of incomplete physiological regulation. DPF describes a state in which fluid distribution, pressure gradients, and regulatory signaling are misaligned, resulting in continued physiological response without restoration of equilibrium. The model is developed through a comparison of two distinct contexts: microgravity and hyperchloremic physiology associated with non–anion gap metabolic acidosis. In microgravity, the absence of gravitational gradients disrupts fluid distribution and degrades the reliability of pressure sensing. In hyperchloremic states, internal regulatory signaling does not accurately reflect physiological conditions, leading to persistent electrolyte and acid–base imbalance despite intact organ function. Across both conditions, regulatory systems remain active and organ systems function, but responses are generated from inaccurate inputs or signals that do not match physiological reality. As a result, fluid redistribution and metabolic clearance do not fully resolve. This paper positions DPF as a unifying failure pattern across environments, reframing microgravity as a model of directional loss and hyperchloremia as a model of signaling distortion. Rather than representing organ failure, these states illustrate a breakdown in alignment between physical conditions and regulatory interpretation. The framework is intended as a conceptual and translational model, providing a structured approach to understanding physiological instability across domains without reliance on a single organ-centered explanation.
Beth Ann Martell (Mon,) studied this question.