Introduction:

Ultrasonography is an indispensable tool in the diagnosis and monitoring of critically ill patients during the last three decades. Currently the diagnosis of hypovolemic shock is made through the monitoring of vital signs, the identification and quantification of blood loss and markers of tissue hypoperfusion. However, it has been amply demonstrated that hypotension and tachycardia are not specific or sensitive to perform such a diagnosis at the same time that they are altered in advanced stages of the shock state, so they are ineffective in the early identification and decision making. of tissue hypoperfusion are expensive and the necessary supplies are not always available.

Methodology:

The collapse of the inferior vena cava was measured in healthy patients before and after the 450 cm3 donation in the state blood bank of Ecatepec during the period from March to August 2017. It was performed in patients between 16 and 65 years of age, who were healthy, who agreed to participate in the study after signing an informed consent letter and in which it was technically feasible to measure the variables with ultrasound, taking as a universe the measurement performed in 87 patients of which 75% were male and 25% were female, inferior vena cava collapsibility was measured before and after performing the 450 cm3 exsanguination, the circulating blood volume and permissible bleeding were calculated, it was calculated the percentage of permissible bleeding equivalent to 450 cm3 in each patient and the blood loss was homologous with the percentage of blood loss proposed by the college of surgeons for the classification of hemorrhagic shock.

Conclusion:

With the universe of patients reviewed, it is proposed to add the measurement of inferior vena cava collapsibility as a complementary, accessible and inexpensive evaluation in the complementation of the diagnosis and monitoring of hypovolemic shock in ICU and emergency patients.