Infusional therapy is one of the main methods of treatment of patients in critical states. It allows to carry out completion of intravascular volume, to carry out correction of electrolytic disturbances, to adjust carrying out parenteral food, administration of antibacterial drugs and so on.
Infusional therapy has to be sufficient on the volume, otherwise the therapeutic effect of it can be not reached. Introduction of enough liquid allows to gain effect necessary for the doctor from the patient's organism: increase in warm emission, improvement of perfusion of fabrics, restoration of normal water and electrolytic balance and so on.
At the same time, implementation of excess infusional therapy can cause the patient's overload liquid, disturbances in work of cardiovascular and respiratory systems, a hypervolemia, different types of an overhydratation. In the last researches it is shown that excess infusional therapy leads to deterioration in outcomes at the patients who are in intensive care units. In this regard, control of correctness and sufficiency of performing infusional therapy is of great importance.
There are several ways of control of sufficiency of infusional therapy in intensive care units. They can be divided into clinical, tool and laboratory. Let's consider one after another each group of indicators.
Clinical data represent the signs revealed at simple clinical inspection of the patient. Treat them: anamnesis, complaints of the patient, consciousness level, condition of integuments, thickness of a hypodermic and fatty fold, these auscultations, pulse rate, noninvasive arterial blood pressure, diuresis volume and so on. For example, the hypovolemic shock at the patient demanding immediate completion of intravascular volume are characterized by existence of cold integuments, a Crocq's disease, decrease in a diuresis. At a palpation of pulse tachycardia is noted, arterial blood pressure decreases. In the started cases consciousness disturbances join. On the contrary, the hypervolemia is characterized by increase in arterial blood pressure, an asthma, damp rattles in lungs, in the started situations there are consciousness disturbances. At dehydration patients show complaints to thirst, increase of pulse rate and a lowering of arterial pressure is observed, the diuresis decreases, thickness of a hypodermic and fatty fold decreases. It should be noted that clinical data need to be compared with tool and laboratory.
Tool inspections include a number of indicators which are measured directly at the patient's bed and also a number of researches which are applied to control of infusional therapy. The most often used indicator reflecting volemia degree at resuscitation patients is the central venous pressure (CVP). This pressure is measured by means of the central venous catheter which tip has to be in the top vena cava. At a sufficient volemia indicators of TsVD are normal, and at a hypovolemia begin to decrease. At a hypervolemia and also at decrease in warm emission, indicators of TsVD begin to grow. It is necessary to understand that volemia assessment by means of TsVD demands observance of all rules of measurement of this indicator.
In addition to TsVD, also more difficult methods of measurement of a volemia, such as pressure of jamming of a pulmonary artery and measurement of warm emission by a termodilyution method can be used, but they demand existence of more difficult equipment.
It is necessary to refer to tool methods of assessment of a volemia as well ultrasonic diagnostics. A key indicator of a volemia at abdominal ultrasonography is diameter of the lower vena cava and change of this diameter in the course of a respiratory cycle. At a hypovolemia the considerable difference in the diameter of the lower vena cava on a breath and on an exhalation is noted. The method is low-invasive, but insufficiently exact in some clinical situations.
Laboratory indicators of a volemia include first of all concentration indicators, such as hemoglobin and hematocrit. At dehydration increase in these indicators owing to concoction of blood because of liquid losses is noted. On the contrary, at a hypervolemia and an overload liquid notes decrease in indicators of hemoglobin and a hematocrit owing to blood cultivation.
In biochemical analysis of blood indicators of level of sodium and osmolarity are important. They allow to diagnose a type of dehydration or overhydratation and to appoint the correct treatment. It should be noted that measurement of indicators of sodium and osmolarity is noted only in case of hypertensive or hypotonic disturbances of a water balance, at isotonic disturbances they will not change.