From Big Medical Encyclopedia

MONITOR OBSERVATION — the long, carried-out for several hours or days keeping track of by a condition of a number of the vital functions of an organism by continuous registration of indicators of these functions (pulse rate and breath, size of arterial and venous pressure, body temperature, the electrocardiogram, etc.).

Fig. 1. Habit view of a cardiomonitor of «Kardiokompleks-2»: 1 — ritmokardiometr; 2 — an electrocardioscope; 3 — an electrostimulator; 4 — the charger; 5 — the cart.

The m of N, or monitoring, is carried out by means of monitors, to-rye represent complexes of medical devices. Depending on complexity monitors divide into three groups: 1) the simple devices intended for overseeing by one-two most important indicators (e.g., an ECG and a respiration rate); 2) devices, in to-rykh the doctor are individually set borders of marginal fluctuations of sizes of observed indicators; at a deviation from them the alarm signal joins and at the same time automatically registration of these indicators can join; 3) devices, to-rye not only register and reproduce the obtained data, but also make their assessment, issue recommendations for acceptance of necessary treatment and control its efficiency. Devices are created, to-rye are not only information complexes, but also include devices for acute management. It is, e.g., the domestic cardiomonitor of «Kardiokompleks-2», the electrocardioscope, ritmokardiometr, an electrostimulator and the charger for autonomous power supply of the device (fig. 1) is a part to-rogo.

«Cardiocomplex-2» provides: overseeing of an ECG in standard leads with a possibility of reproduction in addition one more fiziol, parameter (e.g., the ABP), measurement of average heart rate and the alarm system in case of an exit of this indicator out of the set limits, normalization of a cordial rhythm electric stimulation in the modes of reduction and increase in heart rate. An exit for inclusion of a synchronous defibrillator in case of a cardiac standstill is in addition provided.

Depending on research objectives for M. the N create stationary and portable installations. Most the monitors providing constant tracking at the same time several patients, napr, the domestic DKS4T-0.1 monitor were widely adopted. 4 bedside devices with a complex of primary converters and the central panel supplied with devices of indication and registration are its part. Bedside devices provide continuous control of the measured parameters and give alarm signals at a deviation them for acceptance limits. For keeping track of by changes of the ABP in the monitor it is used pnevmatopressovazometr — the device for continuous measurement of the ABP; indication of body temperature and a respiration rate is made by means of a ritmospirometr. The central panel provides indication of values of parameters with method of the running all over control. Indication of an ECG is carried out on the screen of a 4-beam oscilloscope continuously. Results of measurements constantly register the registrar of slow processes. At a signal «alarm» the monitor automatically carries out record ECG of the patient during 30 sec. by means of the single-channel registrar.

N are implemented methods of the analysis of the obtained information by means of the COMPUTER into M.'s practice more and more widely. Use of the COMPUTER allows to make automatic registration and accumulation of data for issue of information in summary form, to receive new indicators by mathematical processing of basic data, to carry out statistical information processing, to control dynamics of a condition of the patient and to manage nek-ry Therapeutic processes, to make diagnostic assessment of parameters and to predict a state. Complexes of the monitor and COMPUTER use broader set of primary sensors, in addition including discrete data on acid-base balance and analyses of blood gases.

Usually N resort to M. for the purpose of immediate detection of the life-threatening conditions of the patient determined by change of controlled indicators for rendering the emergency medical aid or for identification of such changes, to-rye it is not possible to establish at usual («accidental») observation, and also for the purpose of diagnosis or assessment of frequency of certain phenomena (e.g., extrasystoles) throughout the set time. In the first case use the stationary monitors equipped with the alarm signal which is automatically joining at a deviation of size of a controlled indicator the limits set by the doctor. In the majority of stationary models the recorder, and at the same time turns on in some and system of magnetic memory. Such systems of memory are based on the principle of continuous registration of controlled function for a magnetic ring, with to-rogo in several seconds the written-down signals are erased; at an alarm signal the erasing head is disconnected, and the magnetic record is reproduced on an oscilloscope of the monitor and the recorder that allows to register the data which were directly preceding alarm. In the second case at M. the N who is carried out for identification or assessment of frequency of short-term changes of an ECG the portable devices allowing are used it is long to write down continuously an ECG on slowly moving magnetic tape. The subsequent analysis of an ECG is made by means of electronic decoders, the speed of a broach of a magnetic tape in to-rykh is tens times above, than in the portable monitor. Portable monitors are not equipped with an alarm signal.

The m of N by means of stationary monitors is carried out at treatment of the patients who are under the threat of development of life-threatening complications (disturbances of a heart rhythm, falling of the ABP, an apnoea, etc.). The exception represents the telemetric M. of N applied with the special purpose, napr in a space and air medicine for the purpose of identification of influence of overloads, zero gravity and other factors influencing an organism in flight on nek-ry vital signs. Stationary monitors establish in chambers where there are patients with similar forms of pathology — in resuscitation chambers, blocks of an intensive care for patients with a myocardial infarction, the centers for fight against acute poisonings, micropediatric chambers etc. Sometimes M. of N is applied in thoracic surgery, and also during the use of the managed hypothermia and hypotension.

Depending on M.'s purpose of N one-two indicators are usually controlled: so, at heart operations the ECG and the ABP most often is registered, at poisonings — a respiration rate and an ECG. Control of a large number of indicators is complicated in connection with inevitability of dispersal of attention of the doctor observing not only for indications of devices, but also directly behind a condition of the patient. Need of direct overseeing is a condition of the patient the main reason of creation of special blocks (chambers) for monitor observation. In such blocks M. of N it is carried out at the same time behind several (4 —) patients. Directly at a bed of each patient the so-called bedside monitor equipped with an alarm signal and allowing to estimate parameters of controlled indicators at survey of the patient is located. The data registered by each bedside monitor in the majority of systems are duplicated on the central panel or at the same time from all bedside monitors, or (that is less desirable) selectively, by means of switching. During rounds or survey of the patient one of medics shall be behind the central panel not to see life-threatening changes of controlled indicators at other patients. In some cases the bedside monitor which is not connected with the central panel use as independent funkts, unit (e.g., at operations, carrying out a countershock, in need of M. N for one patient in case of lack of the monitor block).

Due to the development kardiol, services and creation by the USSR of blocks of an intensive care for patients with a myocardial infarction the most wide spread occurance would find so-called cardiomonitor observation in many. The main controlled indicator at the same time is the ECG. Automatic registration of other parameters, especially in blocks of intensive observation for patients with an acute myocardial infarction, is seldom combined with cardiomonitor observation or because of smaller their wedge, the importance during a myocardial infarction (respiratory disturbances, changes of body temperature), or because of methodical difficulties (so, long registration of the ABP by direct methods is dangerous because of a possibility of development of tromboembolic episodes, and available indirect, manzhetochny, methods tire the patient and disturb a dream).

Fig. 2. The diagrammatic representation of options of an arrangement of the electrodes on a thorax applied at long cardiomonitor observation (signs - and + designated positions of electrodes for registration of an ECG in different assignments; the arrow specified the grounding electrode): and — imitation of assignments of V2 and V6 (1 — a position of a chest electrode at which assignment of V2 is imitated; 2 — a position at which assignment of V6 is imitated; — system of assignments according to Marriott — Foggu (1, 2 and 3 — the assignments imitating respectively the standard assignments of V1, V6 and III standard).

Technology of registration of an ECG at cardiomonitor observation has a number of features. A traditional arrangement of electrodes for registration of the standard assignments of an ECG (see. Elektrokardiografiya ) it is not applied since at a similar arrangement any movement of the patient leads to deformation of an electrocardiographic curve and emergence of the artifacts leading to automatic inclusion of an alarm signal. A row of monitor systems of assignments (fig. 2) is offered, to-rykh the principle of placement of electrodes in those points of a thorax where is absent is the cornerstone or there is almost no muscular tissue. The grounding electrode usually fix on edge of a costal arch, on its crossing with the right okologrudinny line, an electrode for the right hand — at the level of II edges on edge of a breast. If at the same time to fix an electrode for the left hand on the VI edge on the left front axillary line, the curve ECG in a form will remind V6 registered in assignment; if to strengthen this electrode in the third mezhreberye on the left edge of a breast, the form of an electrocardiographic curve approaches that, edges is registered in assignment of V2.

Fig. 3. The diagrammatic representation of an electrode for long cardiomonitor observation (and — a sectional view on diameter, 6 — a dorsal view, in — a ventral view): 1 — the plastic case; 2 — the silvered metal plate; 3 — a sticky ring fixer (it is designated by a dotted line); 4 — the camera filled by electrowire paste; 5 — skin.

In a number of cardiomonitor systems non-standard marking of electrodes, napr, is applied black, brown and white color (black — grounding, brown corresponds to assignment from the right hand, and white — from the left hand). The special not rusted electrodes of various designs (fig. 3), and also non-drying electrowire pastes are used that allows to carry out hours-long and even multidaily registration of an ECG without change of electrodes. Electrodes are densely fixed to skin by means of sticky polymeric rings or a usual adhesive plaster. Skin of a thorax is degreased alcohol, indumentum is shaved off if necessary. The ECG continuously is registered on the screen of an oscilloscope (on the central panel multiloop oscilloscopes are used); record it on a paper strip can be made as automatically, on an alarm signal, and at the initiative of the doctor.

Any of the existing stationary monitors, even in connection with difficult COMPUTERS, does not allow to automate overseeing by the patient completely. Almost inevitable malfunctions as disturbance of contact between the sensor and an electronic circuit of the monitor at the movement of the patient in a bed, especially at insufficiently good contact between an electrode and skin, can imitate life-threatening patol, states (an asystolia, an apnoea, fibrillation of ventricles). Cases when in similar situations the medical staff began resuscitation actions are known. At the same time, as show control researches (simultaneous carrying out M. of N by means of ordinary stationary and portable monitors), at usual M. N, despite use of automatic equipment, according to N. A. Masur and O. S. Ryabokon (1979), to 50% of life-threatening arrhythmias remain unregistered. It is connected with insufficient reliability of automatic systems; with the fact that doctors quite often disconnect them because of frequent artifacts; with exhaustion, the oscillographic screen of the stationary monitor, inevitable at hours-long overseeing, on Krom quite often 6 electrocardiograms at the same time are registered; with need to control indicators of other devices and, the most important, directly to watch a condition of the patient. Thus, constructive improvement of M. of N is the major task. Along with it special training and careful professional selection of medical personnel is necessary for M.'s carrying out of N. Despite all told, cardiomonitor observation allowed to lower sharply, and in a row to lay down. institutions practically to liquidate cases of death from primary fibrillation of ventricles at an acute myocardial infarction.

Fig. 4. A fragment of the ECG registered at the daily monitor observation made by means of a portable cardiomonitor at the patient with disturbance of a heart rhythm: and — the moment of transition of sinus tachycardia to a paroxysm of ventricular tachycardia in the assignments imitating the first standard lead (1) and assignment of v1 (2) — it is specified by an arrow (the nature of tachycardia was established further at intracavitary an electrophysiologic research of heart); — the schedule of heart rate which is automatically constructed by means of the decoder in day when monitor observation was made (on ordinate axis heart rate 1 minute is postponed, on abscissa axis — time of day; shooters over a curve: ZhT — the beginning of a paroxysm of ventricular tachycardia, CP — recovery of a sinoatrial rate; shooters under a curve: 1 — raising of the patient on a ladder, 2 — squat, 3 — introduction of 10 mg of Isoptinum intravenously, 4 — reception of 120 mg of Isoptinum inside).

The m of N by means of portable cardiomonitors gains ground in diagnostic practice. Hours-long, daily or multidaily continuous registration of an ECG in most cases allows to reveal the disturbance of a rhythm disturbing the patient which is not revealed by one-time researches, to find various changes of a configuration of an electrocardiographic curve. The possibility of registration of an ECG not only in a hospital is of considerable value at observance by the patient of a general regime, but also in extra hospital conditions when the patient is in a usual situation and it is engaged with usual activity. The portable monitor becomes stronger on the belt thrown through a shoulder of the patient or on an elastic belt. The same systems of assignments are applied, as at stationary M. by N; electrodes have the design similar used in stationary devices. For the analysis of communication of the studied electrocardiographic phenomena with external factors (a dream, food, walking, rise on a ladder, rest, etc.) and subjective feelings (pain behind a breast, feeling of heartbeat, interruptions in cardiac performance) to the patient suggest to keep the detailed diary and compare records in it with changes by the ECG and data of an otmetchik of time. Examples of the ECG registered by means of portable monitors are given in the figure 4. The m of N by means of portable monitors allows to reveal and verify disturbances of a rhythm or manifestation of coronary insufficiency, to count their number for a certain time term and that is especially important, to estimate efficiency of the carried-out therapy.

Portable monitors for registration of other indicators (the ABP, EEG) find more limited application so far and are used preferential for scientific research.

V. A. Bogoslovsky; G. P. Itkin (medical tekhn.).