RU2320275C2 - Method for predicting possible terms of thromboembolism of pulmonary artery after operation - Google Patents

Abstract

FIELD: medicine, surgery.

SUBSTANCE: one should detect hemocoagulation potential (P) by the following formula:

where t - time of plasma recalcification (min), i - prothrombin index, f - the quantity of fibrinogen (mg/l), a - a patient's age (yr), moreover, additionally it is necessary to detect the volume of infusion therapy (ml) (V) and the volume of operational blood loss (ml) (W), and the time for the onset of thromboembolism of pulmonary artery (T) should be determined by the following formula:

EFFECT: higher accuracy of prediction.

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Description

The invention relates to medicine, in particular to surgery, and can be used to predict the duration of a possible occurrence of pulmonary embolism after surgery.

A known method for predicting the possibility of pulmonary embolism using a combination of values of clotting tests. The method involves the use of formula E.V. Roitman in our (Klochkov N.D., Rumakin V.P., Kovalenko Yu.V., 2001) modifications:

Where

P - blood coagulation potential,

t is the plasma recalcification time,

i is the prothrombin index,

f is fibrinogen,

and - the age of the patient.

(Frequency of pulmonary embolism according to the materials of VMedA from 1989 to 1998. // Abstract. Report. Conf. Military-Scientific Society of students and clinical residents of the faculty of leading medical staff. - St. Petersburg, 2001. - P. 42).

This formula worked quite effectively in the logistic regression model to diagnose the development of thromboembolic complications.

The disadvantage of this method is the low accuracy of predicting the time of onset of pulmonary embolism.

The purpose of the invention to improve the accuracy of predicting the time of onset of pulmonary embolism.

The goal is achieved by examining laboratory data and clinical indicators, and the time to onset of pulmonary embolism is determined by the formula:

Where

T is the time of the possible formation of pulmonary embolism (h),

V is the volume of infusion therapy (ml),

W is the volume of operating blood loss (ml),

t is the plasma recalcification time (min),

i is the prothrombin index,

f is the amount of fibrinogen (mg / l),

and - the patient's age (year).

The method is implemented as follows. V is determined as the volume of infusion therapy (ml), W is the volume of operating blood loss (ml), t is the plasma recalcification time (min), i is the prothrombin index, f is the amount of fibrinogen (mg / l), and the patient's age (year) and substitute the obtained values in the formula

thus predicting the time after which the occurrence of pulmonary thromboembolism after surgery is possible.

We give a concrete example from clinical practice.

Patient S., 46 years old, was operated on for gastric ulcer, the volume of infusion therapy was 2000 ml, the volume of operating blood loss was 1500 ml, the plasma recalcification time was 1 min, the prothrombin index was 99, and the amount of fibrinogen was 4 mg / l. Substituting the known parameters into the formula, we determined that the onset of pulmonary embolism in this patient should be expected 1425 minutes after surgery, i.e. almost a day later. Observations of the patient showed that pulmonary thromboembolism was detected after 25 hours, resuscitation measures were taken in a timely manner.

Regardless of the underlying disease and the nature of the operation, the possibility of developing pulmonary embolism after surgery on all material was greatest during the first 24 hours in 46 (15.2%) cases. Starting from 2 days to 7 days, it increased, then remained at the same level until 16 days, sharply decreasing in the subsequent.

It was also found that the timing of the development of pulmonary embolism after surgery can be predicted by factor analysis using the principal component method. Using factor analysis, a model was built for the dependence of the time of onset of pulmonary embolism, including from the numerical value of the hemocoagulation potential. From among 12 factors, 3 factors were selected by the method of principal components, which were identified as the main ones and formed the basis for creating the factor model. The first major factor (V) can be defined as the volume of infusion therapy (r = 0.92). The second major factor (P) is the blood coagulation potential (r = 0.92). The third major factor (W) is the amount of operative blood loss (r = 0.76).

Claims (1)

A method for predicting the period of possible occurrence of pulmonary embolism after surgery, by determining the hemocoagulation potential (P) by the formula

where t is the plasma recalcification time (min), i is the prothrombin index, f is the amount of fibrinogen (mg / l), and is the patient's age (year), characterized in that the volume of infusion therapy (ml) is additionally determined (V) and the volume operating blood loss (ml) (W), and the time of onset of pulmonary embolism (T) development is determined by the formula