Orthostatic test. Why is this research method used?
Problems with the cardiovascular system area compelling reason for seeking medical help. Such diseases often lead to severe complications, disability and even death. For this reason, it is necessary to be examined on time and begin treatment. Pathologies of the cardiovascular system can arise for many reasons and have different manifestations. Some patients have an asymptomatic course of ailments, this complicates timely diagnosis and often leads to decompensation of the process. There are many examinations that allow to assess the state of the cardiovascular system. One of them is an orthostatic test. It is given to patients who are difficult to identify the disease or its cause due to the lack of a characteristic pattern or the initial stage.
Orthostatic test: indications for the study
The study is conducted at variousdiseases associated with the violation of the functions of the cardiovascular system and its innervation. Orthostatic test is necessary for evaluation of blood flow, as in pathologies it can be slowed down or, conversely, strengthened. Most often, with disease, there is a delay in venous return. As a result, various orthostatic disorders occur. They are expressed by the fact that a person can feel discomfort when the position of the body changes from horizontal (or sedentary) to vertical. Most often there is dizziness, darkening in the eyes, lowering blood pressure and fainting. Complications of orthostatic disorders are: ischemia of the heart with the development of angina pectoris and myocardial infarction, collapse. The causes can be not only changes in the blood flow itself, but also the nervous structures responsible for it. In this regard, violations can be associated with both cardiac pathology and the central nervous system. The main indications are: changes in blood pressure (both hyper- and hypotension), insufficiency of the coronary circulation, autonomic nervous system.
Types of orthostatic samples
The study can be conducted in different ways. There is both an active and a passive orthostatic test. The difference lies in the functional load on the patient's muscular apparatus. An active test involves an independent transition of the patient from the horizontal to the vertical position. As a result, almost all skeletal muscles are reduced. To conduct a passive test, a special table is necessary, to which the researcher is fixed. In this case, the load on the muscles can be avoided. This study allows you to assess the state of hemodynamics before and after a change in body position. Normally, each person's main indicators change due to a small change in pressure, as well as due to physical exertion. If the cardiovascular system is insufficient, there is an increase (less often - a decrease) in the difference between blood pressure and heart rate before and after the sample.
Orthostatic test methods
Depending on the type of orthostatic test,the methods of conducting are somewhat different from each other. The most common is the way of Schellong. This method is regarded as an active orthostatic test. How to conduct a study on Schellong?
- The patient lies on the couch, he should be as calm as possible. A special blood pressure meter is connected to it.
- The doctor makes a pulse measurement, then records the results of heart rate and blood pressure for the last 15 minutes.
- The patient is asked to stand up and be in an upright position.
- During this time, a continuous measurement of the pulse and BP occurs.
- The patient lies down again, and the doctor records the results after 0.5, 1 and 3 minutes.
- After the test, a graph of the pulse and blood pressure versus time is plotted.
Interpretation of results
Despite the fact that changes in indicatorsHemodynamics with a change in the position of the body occur in every person, there are average indicators. Deviation from the norm in the direction of increase and decrease in heart rate and blood pressure indicates a violation of the cardiovascular or nervous system. When the patient is lying down or sitting, blood is distributed throughout the body and slows down. When a person gets up, she comes in motion and heads through the veins to the heart. With stagnation of blood in the lower extremities or the abdominal cavity, the orthostatic test parameters differ from normal ones. This indicates the presence of the disease.
Orthostatic test: norm and pathology
When evaluating results, attention is drawn tosystolic and diastolic blood pressure, heart rate, pulse pressure and vegetative manifestations. The ideal indicator is an increase in the heart rate to 11 beats / min, a slight increase in other parameters and the absence of reactions of the nervous system. A slight sweating and an unchanged state of pressure before and after the examination are allowed. It is considered satisfactory to increase the heart rate by 12-18 beats / min. Orthostatic test with a large increase in pulse and diastolic pressure, severe sweating and noise in the ears, a decrease in systolic blood pressure suggests serious hemodynamic disorders.