Genesis of Antibiotic Resistance (AR) LXXXIII: Turbulence Modeling(TM) of Hemodynamics in Simplified Severe Sepsis Protocol‐2 (SSSP‐2)‐NCT01663701: Mechanism(S) of Von Kármán Vortex Street Induced Aberrant Velocity Pattern (Dean Number) Spur In Hospital Mortality (ihm)

Abstract

Based on Flow‐3DÒ Hydro FD simulation Model 04; 05_sediment_transport FLOW‐3D HydroÒ, (Courtesy: Flow‐3D HydroÒ), and clinical hemodynamic data (& derived) from SSSP‐2 trial, here we present a plausible physiological basis for the effect of fluid bolus augmented Von Kármán Vortex Street, thrust velocity profile which may have been the cause that leads to 100% ihm usual care cohort of SSSP‐2 (PMID: 28973227). Hypothesis:Fluid bolus‐induced fluid volume expansion causes the cerebral vessel collapse by a secondary flow of fluid moving away from the vessel wall (boundary layer separation). Rationale:The Dean number (De) is the ratio of the viscous force on the fluid flowing in a curved pipe to the centrifugal force. When the fluid flow fails to develop at the inlet, a possible vortex in the core of the fluid could incur velocity skewing towards the inner wall of the curve. However, if the fluid flow is fully developed the velocity skewing could be toward the outer wall. A secondary flow may develop as a counter‐rotating vortices in the center of the tube tending the flow to move towards the outer side which could be separated by high De along the inner wall. Pulsatile flow is also known to induce secondary flow through the curvature of blood vessels by three possible types of velocities formed by the fluid flow namely a. axial velocity(nz), b. radial velocity(nr), c. angular velocity(nq). Geometry: Approximate geometry, blood velocity and function of human blood vessels, Table 2.1 p63; BP range in systemic and pulmonary circulation vessels for a normal adult, Table 2.3, p64. ISBN 978012802408‐9. Governing Equation: Part A: Dean Number (De) is the ratio of viscous force on a fluid flowing in a curved pipe to the centrifugal force. The De for a channel or curved pipe is defined as: De=Re ·√Dh/2R, where Re = Reynolds number, Dh = hydraulic diameter (m), R=radius of the curvature of the pipe (m) (p18, Equation: 1.21). Derivation:Based on the hemodynamic parameters (BP, MAP, PP, RR, JVP, SAPS‐3 score, of SSSP‐2 (PMID: 28973227), baseline characteristics of patients (Table 1, p1237) and elements of fluid resuscitation (Table 2, p1238), it is suggested that blood vessel outlet with low De, likely to have fluid flow pattern shown in Fig 2.12 panel 2, within 6hrs after the ERP‐Fluid bolus in usual care and SSSP‐2 protocol cohort. However, after 6 hrs. fluid flow patterns in the vessel outlet of usual care, with high De as presented in Fig 2.12, panel 3. Prospects:Taken together, an increase in von Kármán vortex street in turn, caused an increase in ZoO, stalling of the fluid flow, the consequent increase in pressure at the upstream of ZoO, compared to that of downstream causing a burst in cerebral arteries and in turn ihm. A clinical correlation defines, aforesaid state as “distal ischemic steal syndrome (ISS), caused by a substantial decrease or even reversal of blood flow (“steal”) through the cerebral arteries. Such clinical manifestation may have been the cause for the increase in CPPopt resulting in a 100% ihmin usual care.