The need for a physiological classification of hemorrhagic shock

Abstract

Classifications mean to conceptualize in a cluster and rapidly summarize the assessment and management of a clinical scenario. In the specific case of a hemorrhagic shock (HS), a classification should serve the purpose of allowing a rapid clinical assessment of the shock level and the earliest or right timing of source control, possibly also on whether to apply damage control surgery (DCS) strategy or not. ATLS ® classification of HS is not sensitive and specific enough to help decision-making in reference to the timing of management, based only on the amount of blood loss that may be or may not rightly estimated, for example, blood loss on the floor in penetrating injuries before theatre. Moreover, it focuses also on other parameters, which are taken singularly, instead of the individual generalized physiological response to hemorrhage, which is the core by definition of the derangement we call “shock.” It is unhelpful, difficult, and impractical to apply as well. A new classification, which may well be called as the “physiological HS classification” or “therapeutic HS classification,” was proposed since 2010, following the new developments on microcirculation and an already going-on sensible praxis among some trauma surgeons. It bases on some physiological considerations such as the significance of fluid-blood resistant hypotension, body natural hemostatic mechanisms, the right definition of shock, and the relevance that hemorrhage-triggered ischemia-reperfusion toxemia and systemic inflammatory response have in critical illness scenarios as secondary insults from ischemia, which is what we mean to prevented with DCS. The key factor remains the persistence of hypotension, following fluid challenge.

Distinct morphologies of arterial waveforms reveal preload‐, contractility‐, and afterload‐deficient hemodynamic instability: An in silico simulation study

“…values from the literature, suggesting that the simulations produce realistic scenarios for HD instability and circulatory shock. In the simulation, a maximum BV reduction of 32% was reached, comparable with the 30% of total blood volume loss reported as a threshold for hypotensive shock due to hemorrhage (Bonanno, 2020). SVR was decreased till 0.22 mmHg*s/ml, which is much in line with the reported 0.33 mmHg*s/ml in septic patients (Melo & Peters, 1999).…”

In-Hospital and Long-Term Outcomes in Patients with Head and Neck Cancer Bleeding

“…Patients may expire in a short period if they develop hemorrhagic shock. Hemodynamic status is a plausible prognostic factor in patients with massive hemorrhage because hypovolemia and vasoconstriction contribute to tissue hypoperfusion and multiorgan failure [28][29][30][31].…”

Reanimación de control de daños: un enfoque racional para la atención del paciente politraumatizado

“…Tradicionalmente se han utilizado estos parámetros para clasificar el grado de choque en cuatro categorías según el volumen de sangre perdida 2,4 . Sin embargo se ha cuestionado la precisión de esta metodología, dada la variabilidad en la relación entre la pérdida sanguínea y el valor de estos parámetros, haciendo que solo el 10% de los pacientes con choque hemorrágico se puedan categorizar correctamente según esta clasificación 12 . Como alternativa se ha propuesto una combinación de parámetros clínicos y de laboratorio para identificar a los pacientes con sangrado importante y predecir en ellos la necesidad de trasfusión masiva (TM) y otras intervenciones 4,11 .…”