RU2277848C2 - Method for preventing ischemia of spinal cord due to regulating hemodynamics in patients with affected spinal cord - Google Patents

Abstract

FIELD: medicine, resuscitation.

SUBSTANCE: intensive therapy should be carried out, moreover, it is necessary to register somatosensor evoked potentials (SSEP), measure inter-peak interval N₁₃-N₁₈ at spinal lesions at C₁-C₂ level, N₁₁-N₁₃ at lesion at C₁-C₆ level and N₂₂-C₃₀ at lesions at C₇-L₃ level. Then one should calculate average arterial pressure (AP_av) and prescribe pressure-regulating medicinal preparations. Then comes control SSEP registration and at decreased values of inter-peak intervals one should change the preparation applied and its dosage, at constant level of inter-peak intervals - the dosage should be increased, and at increased values of intervals - one should intensify therapy due to increasing the dosage or substituting the preparation applied. SSEP values should be evaluated after changing the dosage of the preparation applied and in dynamics of investigation on the 3d, 5^th and 9^th d and, also, in case of deterioration of patient's health state. It has been provided due to applying a high-sensitive value that reflects the state of spinal cord.

EFFECT: higher efficiency of prophylaxis.

3 ex

Description

The method relates to medicine, namely to resuscitation, and can be used to treat patients with spinal cord lesions.

With any acute damage to the spinal cord, whether it is the result of an injury or surgical intervention (for example, due to a tumor), in addition to its instant damage, which is a direct result of an injury or medical manipulation, a slow destructive process develops, the consequences of which are no less significant. Among the variety of pathophysiological mechanisms of secondary damage to the spinal cord, an important role is given to vascular factors, which are understood as microcirculatory changes leading to spinal cord ischemia proximal and distal to the site of damage, and general vascular effects - hypotension and decreased cardiac output, which significantly change the functioning of all organs and systems of the body. General vascular effects are most pronounced with a high level of damage (cervical, upper chest). Since impulse to and from the vasomotor center is blocked, vascular tone disappears, and the capacity of the vascular bed increases so much that the volume of circulating blood is not enough to maintain normal blood circulation. The absence of vasomotor reactions leads to sharp, often fatal circulatory disorders with a change in the patient’s body position. Thus, it is necessary to use vasopressors to maintain blood pressure (BP) at the required level. At the same time, situations when spinal patients have a need to lower blood pressure are not uncommon.

The implementation of controlled monitoring of the auto-destructive process is the most effective approach to restoring lost links between the central nervous system and working organs. In the very first hours after surgery, it is necessary to create the most favorable conditions for the flow of reparative mechanisms through conservative measures. At the moment, the most accessible form of exposure in the conditions of resuscitation department on the ischemic component of spinal cord injury is drug therapy: a change in the rheological properties of blood, an effect on the coagulation system and vascular tone. However, the approach to choosing the optimal level of mean arterial pressure (SBP) as a synthetic indicator of the adequacy of cardiac output to the volume of the vascular bed (vascular tone) for a particular patient remains empirical, despite its ultimately predictive value. Correction of hypotension (and hypertension, the development of which is also possible) should balance between the risk of secondary intramedullary hemorrhages due to hypertension and hyperemia on the one hand and the need for sufficient perfusion of the damaged area of the spinal cord on the other. It is necessary to facilitate the existence and restoration of the affected structures of the spinal cord and to observe the hemodynamic interests of the organism as a whole (but, of course, these interests are enclosed in a less rigid framework).

A known method of non-invasive determination of cerebral oximetry in the para-infrared range. It allows you to evaluate the compliance of the delivery and consumption of oxygen by the brain and vascular regulation: S.V. Tsarenko, V.V. Krylov, D.N. Tyurin, V.V. Lazarev, D.L. Tsymlyakov, A.V. Karzin. Cerebral oximetry in the para-infrared range. Possibilities of use in the conditions of neuroresuscitation department. // Anesthesiology and resuscitation. - 1998 - No. 4 - P.43-47.

The cerebral oximetry method consists in the fact that a special sensor is placed on previously treated skin of the patient, which is free of hairline. The preferred location of the sensor over one of the frontal areas. Through the cable, the sensor is connected to the oximeter itself. The screen displays the current values of cerebral blood saturation in the studied region of the brain, as well as the trend of the indicator. It reflects the oxygen saturation of the blood of the brain itself, and not the scalp: Cerebral oximetry in dead subjects / Schwarz G., Litscher G., Kleinert R., et al. // J. Neurosurg Anest. - 1996 .-- 8 (3). - P.189-93, and venous, since it is known that the vascular bed of the brain is 80% composed of venous vessels.

The disadvantage of this method is that it is designed to diagnose cerebral ischemia (that is, in fact, to assess the effectiveness of cerebral microcirculation) and it is possible to judge the state of cerebrospinal circulation only indirectly. The most correct way to use this method is only with an injury to the upper cervical spine, when the medulla is suffering. And another significant drawback is that the influence of the state of central hemodynamics on the affected area of the spinal cord is not monitored.

There is a method of calculating and measuring indicators of the oxygen transport system: delivery, consumption, disposal: Intensive care: trans. from English add. // ch. ed. A.I. Martynov - M .: GEOTAR MEDICINE, 1998 .-- ISBN 5-88816-025-3. The ICU book // Paul L. Marino // Philadelphia, Williams & Wilkins. - ISBN 0-8121-1306-3. - S. 27-35. It lies in the fact that they determine the content of blood oxygen: bound to hemoglobin (Hb) and in a free or dissolved state. The total amount of gas in both fractions is called the oxygen content in the blood (CaO ₂ ). The oxygen content in arterial blood is determined by the formula taking into account the level of Hb equal to 14 g.%, Saturation of Hb with oxygen (SaO ₂ = 98%) and the partial pressure of O ₂ (pO ₂ ) in the blood (paO ₂ ), which is 100 mm Hg

Oxygen delivery (DO ₂ ) is the rate of oxygen transport by arterial blood, which depends on the amount of cardiac output (SV) and oxygen content in arterial blood. Normally, DO ₂ is determined with CaO ₂ equal to 18 vol.%, And a cardiac index of 3 l / (min · m ² ), according to the formula.

The consumption of oxygen (VO ₂ ) is the final stage of oxygen transport to tissues and represents the oxygen supply of tissue metabolism. The Fick equation defines oxygen consumption as a derivative of cardiac output (SV) and arteriovenous difference in oxygen content (CaO ₂ -CvO ₂ ).

The absorption of oxygen from capillaries is carried out depending on its metabolic needs (except in cases of impaired ability to extract oxygen from capillary blood). When oxygen uptake worsens, VO ₂ will determine the rate of metabolic processes. This situation usually occurs in patients in critical conditions, and is described in detail in sepsis, multiple trauma, burns. Therefore, VO ₂ as an indicator of the metabolic rate in these cases should be determined in each patient.

The oxygen utilization coefficient (KUO ₂ ) is the part of oxygen absorbed by tissues from the capillary bed; KUO _{2 is} defined as the ratio of oxygen consumption to its delivery.

The rate of oxygen delivery under normal conditions significantly exceeds consumption - this allows tissues to adapt to a decrease in oxygen delivery by increasing its utilization. KUO ₂ during heavy muscular work is able to increase up to 60-80% (at rest KUO ₂ is usually equal to 22-32%).

From the foregoing, it follows that the described technique allows us to consider the changes occurring in the body as a whole. But the use of these indicators in patients with spinal cord injury does not stand out, their use for assessing precisely cerebrospinal circulation is not considered.

As a prototype, we chose the method of Belova A.N., Perlmutter O.A. Rehabilitation in the acute and early periods of spinal cord injury - in the book: Neurorehabilitation, M., Antidor, 2000, pp. 363-380.

This method is aimed at drug therapy without taking into account the functional state of the spinal cord. It does not allow in the early stages to diagnose the development of ischemic complications and prevent their treatment.

The objective of this method is the prevention and early detection of secondary ischemic changes by selecting the optimal level of mean arterial pressure (SBP) for a patient with spinal cord injury using an additional study of somatosensory evoked potentials (SSEP), optimization of the treatment process, which ultimately should contribute to both it is possible to more fully restore the structure and function of the affected spinal cord.

The task is achieved in that a patient with spinal cord injury during intensive care, with constant monitoring of hemodynamics and blood pressure with the calculation of SBP, additionally assesses the functional state of the spinal cord at the level of damage. To do this, the evoked potentials of the SSEP are recorded and the peak-to-peak intervals are measured: N ₁₃ -N ₁₈ , - when the spinal cord is damaged at the level of C ₁ -C ₂ vertebrae; N ₁₁ -N ₁₃ - for damage to the cervical spinal cord C ₁ -C ₆ , N ₂₂ -N ₃₀ - for damage at the level of C ₇ -L ₃ . They are taken as the source. Calculate mean arterial pressure (SBP) and prescribe drugs that regulate blood pressure. Then again carry out control registration SSVP. If the values of the peak-to-peak intervals are reduced, then this is assessed as an improvement in the condition of the spinal cord and the selected drug and dosage are left unchanged. At a constant level of inter-peak intervals, the condition of the spinal cord is assessed as unchanged and the dose of the drug is increased. If there was an increase in the values of the spikes, this is estimated as a deterioration of the spinal cord. In this case, intensification of therapy is carried out, increasing the dose or replacing the drug. The SSEP indicators are evaluated after changing the dosage of the drug to monitor the results achieved and in dynamics, conducting studies on 3, 5, 9, days, as well as when the patient's condition worsens.

The novelty of the method:

- additionally assess the functional state of the spinal cord at the level of damage using SSEP, measuring the peak-to-peak intervals: N ₁₃ -N ₁₈ - with damage to the spinal cord at the level of C ₁ -C ₂ vertebrae; N ₁₁ -N ₁₃ - for damage to the cervical spinal cord - C ₁ -C ₆ , N ₂₂ -N ₃₀ - for damage at the thoracic and lumbar levels - C ₇ -L ₃ ;

- after that, they calculate the SBP and prescribe drugs that change it, under the control of the SSVP, following the trends in the intervals;

- indicators of SSVP are evaluated after changing the dosage of the drug to monitor the results achieved and in dynamics, conducting research on days 3, 5, 9 or when the patient worsens.

The proposed method, based on the use of a highly sensitive and dynamic indicator, improves the efficiency and quality of diagnosis of patients with spinal cord lesions. The quality of treatment is improved by maintaining an optimal level of mean arterial pressure (SBP) by quickly selecting medications, assessing the quality of their effects, and if necessary replacing them, which ultimately leads to better restoration of the structure and functions of the damaged spinal cord.

Changing the peak-to-peak intervals obtained during the study of SSEP for any level of spinal cord damage is, in contrast to the clinical and neurological manifestations, a highly sensitive and dynamic indicator of the state of the spinal cord, depending on hemodynamics. At the same time, each level of damage corresponds to its own inter-peak interval: N ₁₃ -N ₁₈ - with damage to the spinal cord at the level of C ₁ -C ₂ vertebrae; N ₁₁ -N ₁₃ - for damage to the cervical spinal cord - C ₁ -C ₆ , N ₂₂ -N ₃₀ - for damage at the thoracic and lumbar levels - C ₇ -L ₃ , a N ₁₃ -N ₁₈ - must be assessed for damage spinal cord at the upper cervical level - C ₁ -C ₂ when there is a risk of damage and the medulla oblongata: Gnezditsky V.V. Evoked brain potentials in clinical practice. - M .: "MEDpress-inform", 2003. - S.93-111.

The method is as follows: make an individual selection of medications based on the sequential test use of vasoactive drugs under the control of SSVP. The advantage of this approach is a quick assessment of the effectiveness of drugs, based on the high sensitivity of SSEP.

SSEPs reflect the conduct of an afferent excitation wave along the pathways of general sensitivity, passing mainly in the posterior columns of the spinal cord, then through the stem sections of the brain and through the spinal thalamic tracts to the cortex. With damage to the spinal cord and brain, the severity of SSEP at various levels of leads varies significantly: Gnezditsky V.V. Evoked brain potentials in clinical practice. - M .: "MEDpress-inform", 2003. - S.93-111.

Topically SSVP is obtained from the upper or lower limb:

- to assess the condition of the cervical spinal cord using the record obtained by stimulation of the upper limb (median nerve). The median nerve, which carries sensitive impulses mainly from the thumb and forefinger through the brachial plexus, enters at the cervical level C ₆ -C ₇ in the posterior horns of the spinal cord in its ganglia; then there is a switch at the level of the medulla oblongata, in the nuclei of the wedge-shaped bundle (n.cuneatus), and through the mesencephalon (spinal thalamic tract) passes into the ventrolateral nuclei of the thalamus, where after switching the beam of ascending sensitive afferentation is directed to the somatosensory cortex;

- if the thoracic or lumbar spinal cord is damaged, recording is made from the lower extremity (the tibial nerve is stimulated). Fibers from the tibial nerve go a longer way: the tibial nerve enters the posterior horns of the spinal cord at the sacral level, rises to the level of the medulla oblongata, where it switches to the nuclei of the tender bundle, and then through the midbrain, the ventrolateral nuclei of the thalamus rise to the area of the primary projection of the leg .

Nerves are stimulated percutaneously. When stimulating the upper extremities, the stimulating electrode is installed in the projection of the median nerve on the wrist, while stimulating the lower extremities - on the inside of the ankle. The cathode of the stimulating electrode should be located proximal to the anode. The grounding electrode is installed proximal to the stimulating one. Bipolar stimulation is performed by a monophasic rectangular current pulse with a duration of 0.2-0.3 ms, the stimulation frequency of 3-5 Hz. The strength of the stimulus is selected individually, so that a slight reflex movement of the thumb, respectively, of the arm or foot, is visible. The era of analysis for recording from the upper limb is 50-70 ms, for recording from the lower - 70-100 ms. The number of averages is 1000.

Use bipolar leads:

1) when recording from the upper limbs

- C _VI -Fz, where C _VI is the active electrode over the region of the spinous process of the C _VI vertebra, Fz is the reference electrode over the region of the nose;

- Erbi-Fz, where Erbi is the active electrode over the brachial plexus region.

2) when recording from the lower extremities

- Cz-Fpz, where Cz is the active electrode superimposed on the crown, Fpz is the passive electrode on the nose;

- L _III -R, where L _III is the active electrode above the third lumbar vertebra, R is the reference electrode at a point 6 cm from the active electrode.

To assess the functional state of the spinal cord, peak-to-peak intervals were used, the extension of which is 0.2 ms longer than the norm indicates a slowdown in the corresponding parts of the spinal cord (norms are given for persons aged 24-40 years with an increase of 160-180 cm, for other parameters there are nomograms):

1) N ₁₃ -N ₁₈ - norm 5.8 ms ± 0.5 ms - evaluates the spinal cord - thalamus (used for damage at the upper cervical level - C ₁ -C ₂ , when there is a risk of involvement of the medulla oblongata);

2) N ₁₁ -N ₁₃ - norm 12.0 ± 1.0 ms - conducting along the cervical spinal cord (used for injuries of the cervical spinal cord - C ₁ -C ₆ );

3) N ₂₂ -N ₃₀ - norm 7.65 ± 1.04 - conducting along the ascending paths of the entire spinal cord (used for damage to the chest and lumbar regions - C ₇ -L ₃ ).

The SSVP study was conducted on a Dantec Neuromatic 2000 C apparatus.

After the initial study and registration of SSEPs, the patient is selected with a dose of vasoactive drugs that supports blood pressure at a level that provides the optimal functional state of the spinal cord for this stage. Usually, these are normotensive values: GARDEN = 80-100 mm Hg. GARDEN is calculated by the formula: GARDEN = HELL diast. + BP pulse. / 3, where BP is pulse = BP syst. - HELL diast.

For example, a GARDEN of 100 mm Hg was achieved. Art. After that, a control study of SSEP is carried out, revealing a deterioration or improvement in the condition of the conduction paths of the spinal cord, expressed in a change in the main criteria for deviation from the norm or the initial state before therapy - this allows you to determine the effect of the selected blood pressure on the functional state of the spinal cord. And if necessary, the level of the supported GARDEN can be reduced or increased by changing the dosage of the drug or by replacing it.

If the values of the peak-to-peak intervals are reduced, then this is assessed as an improvement in the condition of the spinal cord and the selected drug and dosage are left unchanged. At a constant level of inter-peak intervals, the condition of the spinal cord is assessed as unchanged and the dose of the drug is increased. If there was an increase in the values of the spikes, this is estimated as a deterioration of the spinal cord. In this case, intensification of therapy is carried out, increasing the dose or replacing the drug.

The study of SSEP in dynamics on the 3rd, 5th and 9th day of the postoperative period will make it possible to objectively judge how the conduction paths of the spinal cord are being restored and, if necessary, make changes to the therapy of hemodynamic disorders in patients in the acute period of spinal cord injury, which ultimately optimizes treatment process.

Clinical example No. 1:

Patient B.L., 40 years old, medical history No. 747, was admitted to the clinic on 05/10/03 at 11 hours 35 minutes. She was injured after falling from a height of her own growth on her back. The patient's condition is serious. In the mind. After the examination, which included a clinical and neurological examination, X-ray (chest x-ray and spinal X-ray), a general blood test, a general urinalysis, ECG, the diagnosis was made: Closed spinal cord injury. Closed complicated symmetric mated dislocation of a C ₆ vertebra. Syndrome of incomplete conduction disturbance of the spinal cord from a given level.

The patient was admitted to the Department of Neuroresuscitation 10.05.03, in an extremely serious condition after surgery: Laminectomy C ₆ vertebra. Open reduction of dislocation of the C ₆ vertebra. Interdisc fusion of C ₅ -C ₇ titanium wire and protacryl. She was in the neuroresuscitation department for 15 days, after which she was transferred to the neurosurgery department for further treatment.

At admission: HELL - 80/35 mm RT. Art., frequent group atrial extrasystoles according to ECG, artificial lung ventilation, drug sedation, relaxation were performed, due to the extremely serious condition, pulmonary artery catheterization was performed for invasive monitoring of central hemodynamics.

An SSEP study was carried out using the Dantec Neuromatic 2000 C apparatus upon admission to the department: indicator N ₁₃ -N ₁₈ was 5.8 ms (normal 5.8 ± 0.5 ms) - the medulla oblongata is not involved in the pathological process and further monitoring of this interval is not necessary, and the indicator N ₁₁ -N ₁₃ - 13.8 ms (normal 12 ± 1.0 ms) - which indicates a slowdown in the cervical spinal cord.

In order to correct hemodynamic disorders, the patient was prescribed dopamine intravenously at a dose of 10 μg / kg. Against the background of the introduction of the drug, the hypokinetic type of blood circulation changed to normokinetic - blood pressure - 120/80 mm Hg, i.e. GARDEN = 93 mmHg

Control study of SSEP (immediately after dose selection): indicator N ₁₁ -N ₁₃ decreased to 13.4 ms. Improving the functional state of the spinal cord allows us to conclude that the chosen level of GARDEN is favorable.

After 8 hours, another study of SSEP was carried out: no changes in the functional state of the spinal cord were detected - N ₁₁ -N ₁₃ is still 13.4 ms.

On the 3rd day (05/13/03), the patient's condition was serious, but some improvement was noted: the patient was transferred from the forced ventilation mode to the alternating ventilation mode, independent breaths appeared, hemodynamic reactions were less pronounced during treatment and diagnostic procedures. The value of the indicator N ₁₁ -N ₁₃ , according to the results of the SSVP study, decreased to 13.2 ms. It was decided to reduce the dose of dopamine to 6 mcg / kg - recorded SBP = 87 mm Hg. (HELL = 120/70 mmHg, hyperkinetic type of blood circulation). A control study of SSEP did not show a change in the functional state of the spinal cord - N ₁₁ -N ₁₃ - 13.2 ms.

On the 5th day (05/15/03), the patient changed the alternating regime of mechanical ventilation to support pressure, positive neurological dynamics can be traced - movements are made in the joints of the hands with overcoming the severity of the limb. The functional state of the spinal cord without changes is N ₁₁ -N ₁₃ - 13.2 ms. The dose of dopamine was left unchanged.

On the 9th day (05/19/03) N ₁₁ -N ₁₃ is 12.6 ms - it came to normal. After cancellation of support by vasopressors: HELL = 100-110 / 80 mm Hg (GARDEN = 90 mm Hg); N ₁₁ -N ₁₃ - 12.8 ms - kept within normal limits. Thus, the patient’s body is able to independently maintain adequate hemodynamic parameters and provide the necessary microcirculation in the affected area of the spinal cord.

On the 14th day (05.24.03), the patient was transferred to the neurosurgical department.

Clinical example No. 2:

Patient M.S., 19 years old, medical history No. 1392, was admitted to the clinic on 4.08.02 at 14 hours 10 minutes. He was injured while diving into a pond. The patient's condition is extremely serious. A standard examination was carried out: a clinical and neurological examination, X-ray (chest x-ray and spine radiography), general blood test, general urine analysis, ECG. Diagnosis: Closed spinal cord injury. Cross-shaped comminuted fracture of the C ₄ vertebra. Partial spinal cord conduction disorder from this level.

The patient was admitted to the department on 4.08.02 after surgery: Posterior fusion for arches C _3-4-5 . Anterior spinal fusion with C _4-5 (metal implant) autobone. The condition is extremely serious: decompensation in respiration and hemodynamics (BP = 75/40 mm Hg, rapidly decreasing during manipulations with the patient), neurologically - tetraplegia.

Upon admission to the department according to the SSVP study (using the Dantec Neuromatic 2000 C device), the cervical spinal cord was slowed down - N ₁₁ -N ₁₃ was 14.4 ms (normal 12 ± 1.0 ms), at N ₁₃ -N ₁₈ = 5.85 ms (normal 5.8 ± 0.5 ms). To compensate for hemodynamics, the patient was prescribed dopamine at a dose of 15 μg / kg and mesatone - 2 ml of a 1% solution. GARDEN reached 98 mmHg (HELL = 125/85 mm Hg). A control study of SSEP showed a deterioration in the functional state of the spinal cord - N ₁₁ -N ₁₃ was 14.88 ms, N ₁₃ -N ₁₈ - 5.9 ms. This level of SBP caused a negative dynamics of indicators. The dose of dopamine was reduced to 10 μg / kg - SBP decreased to 83 mm Hg. (HELL = 110/70 mmHg) - indicator N ₁₁ -N ₁₃ returned to the previous value of 14.4 ms, N ₁₃ -N ₁₈ became equal to 5.85 ms. It was decided not to raise the GARDEN above 83 mm Hg.

8 hours after the patient’s admission to the department, the functional state of the spinal cord remains unchanged - N ₁₁ -N ₁₃ = 14.4 ms, N ₁₃ -N ₁₈ = 5.85 ms.

On the 3rd day (7.08.02), the patient's condition remains extremely severe. No positive dynamics of neurophysiological indicators can be traced (N ₁₁ -N ₁₃ = 14.4 ms, N ₁₃ -N ₁₈ = 5.85 ms). An attempt was made to raise the GARDEN: with the GARDEN = 93 mm Hg. (HELL = 120/80 mmHg) indicator N ₁₁ -N ₁₃ = 14.8 ms, N ₁₃ -N ₁₈ = 5.95 ms (conduction along the medulla oblongata also worsened). With a decrease in SBP to 80 mm Hg spinal cord conductivity also worsened - N ₁₁ -N ₁₃ = 14.6 ms, N ₁₃ -N ₁₈ = 5.85 ms. Therefore, it was decided not to change the level of SBP (83 mmHg) and leave the patient at the same dose of dopamine and mesatone.

On the 5th day (9.08.02), the patient's condition without significant dynamics. But in the study of SSEP - a slight deterioration - N ₁₁ -N ₁₃ increased to 14.6 ms, N ₁₃ -N ₁₈ - up to 6.0 ms (edema of the medulla oblongata is possible). After increasing the dose of dopamine to 12 mcg / kg, the SBP increased to 90 mmHg. (HELL = 120/75 mmHg) and it was possible to improve the functional state of the spinal cord to the previous level - N ₁₁ -N ₁₃ = 14.4 ms, N ₁₃ -N ₁₈ = 5.85 ms.

On the 9th day, the general condition of the patient improved slightly: the patient was transferred to an intermittent ventilation mode, hemodynamic lability disappeared, and weak contractions of the muscles of the hands without movement in the corresponding joints were recorded. But the functional state of the spinal cord remains unchanged. Adjustments were made to therapy: mesatone was canceled and the dose of dopamine was reduced to 5 mc / g. Against this background, SBP = 80 mm Hg is maintained. and the conduct along the spinal cord does not change - N ₁₁ -N ₁₃ = 14.4 ms, N ₁₃ -N ₁₈ = 5.85 ms. On the 10th day, dopamine is canceled, there are no dynamics in neurophysiological indicators.

The patient was treated in the intensive care unit for 17 days and was transferred to the neurosurgical department without a significant improvement in conductivity (N ₁₁ -N ₁₃ = 14.2 ms, N ₁₃ -N ₁₈ = 5.8 ms) and without dynamics in neurological status.

Clinical example No. 3:

Patient K.N., 31 years old, medical history No. 1531, was admitted to the clinic on 06.10.03 at 6 hours 10 minutes. Injury received when falling from 2 floors in a state of intoxication. The patient's condition is serious. A standard examination was performed: clinical and neurological, radiological (chest x-ray and spine radiography), general blood test, general urine analysis, ECG. Diagnosis: Closed spinal cord injury. Compression fracture of the Th ₈ vertebra, fracture of the intraarticular processes of Th ₈ and Th ₇ vertebrae with spinal canal deformity by the Th ₈ vertebral body and spinal cord injury. Partial spinal cord conduction disorder syndrome with a Th ₈ level.

The patient was admitted to the neuroresuscitation department on 06.10.03 after surgery: Laminectomy Th _7.8 , revision of the spinal cord, fusion with wire and protacryl Th _5.6 -Th _9.10 . The condition is extremely serious: deep stunning, respiratory decompensation - performed mechanical ventilation, blood pressure = 160/110 mm Hg, neurologically - sluggish lower paraplegia.

The department conducted a study of SSEP on the apparatus "Neuromatic 2000 C" company "Dantec". The recording was made during stimulation of the lower extremities. The interval N ₂₂ -N ₃₀ with a norm of 7.65 ± 1.04 ms was 13.0 ms, which indicates a gross slowdown in the conduct along the spinal cord. It was decided to reduce the SBP to the upper limit of the norm; for this, the patient was prescribed sodium nitroprusside intravenously at a dose of 1.5 μg / kg. Blood pressure decreased to 130/90 mm Hg. - GARDEN = 103 mm Hg Against this background, the condition of the spinal cord worsened: N ₂₂ -N ₃₀ increased to 13.3 ms. The dose of sodium nitroprusside was reduced to 1.0 μg / kg. GARDEN reached a level of 113 mm Hg. (HELL = 140/100 mm Hg) - the dynamics was positive - N ₂₂ -N ₃₀ decreased to 12.7 ms. The dose of the drug was considered optimal.

The next day (10/07/03) the patient's condition is extremely serious, but stable. In the study of SSEP N ₂₂ -N _{30 it} remained practically unchanged - 12.6 ms, but the SBP at a dose of sodium nitroprusside of 1.0 μg / kg was 103 mmHg. (HELL = 130/90 mmHg). They tried to reduce the dose to 0.75 mcg / kg - N ₂₂ -N ₃₀ again increased to 13.0 ms. Therefore, they returned to the previous dose.

10.10.03 - 3 days: the patient is conscious, general condition without significant dynamics, neurologically there is no dynamics either. When studying SSEP, the indicator N ₂₂ -N ₃₀ is at the same level - 12.7 ms. There is no need to change the therapy.

On the 5th day (11.10.03), the patient's condition improved slightly: they transferred to spontaneous breathing with moistened oxygen. Neurologically - weak positive dynamics: the anesthesia zone decreased from the mid-chest level to the lower chest level. In the control study of SSVP N ₂₂ -N ₃₀ = 12.6 MS. After the abolition of sodium nitroprusside at SBP = 90 mm Hg (HELL = 130/70 mmHg) - registered N ₂₂ -N ₃₀ = 12.6 ms.

On the 6th day, the patient was transferred to the neurosurgery department.

Our method, unlike the prototype, allows non-invasive monitoring and objective assessment of the effect of certain values of SBP on the functional state of the spinal and medulla oblongata for the diagnosis and prevention of ischemia of the affected area, leading to aggravation of the severity of the primary damage.

The method allows:

- promptly, in the acute period, when it is still impossible to trace the clinical manifestations of ischemia in a non-invasive way, to obtain data that can diagnose this condition by using a highly sensitive and dynamic indicator of the state of the spinal cord, which depends on hemodynamics;

- substantiate approaches to the correction of hemodynamic disturbances in patients in the acute period of spinal cord injury (trauma, surgery for a tumor, etc.);

- timely diagnose and prevent secondary ischemia of the affected spinal cord;

- to optimize the treatment process by controlling the dynamics of recovery processes in the spinal cord, selecting drugs and their dosages specifically strictly individually for each patient in accordance with his condition, this allows to reduce the drug load on the patient, without reducing the quality of treatment.

We proposed a criterion - a change in the spikes obtained during the study of SSEP, at any level of spinal cord damage, which, unlike clinical and neurological manifestations, is a highly sensitive and dynamic indicator reflecting the state of the spinal cord depending on hemodynamics. The proposed method, based on the use of this indicator, improves the efficiency and quality of diagnosis of patients with spinal cord lesions. It improves the quality of treatment by maintaining an optimal level of mean arterial pressure (SBP) by quickly selecting, evaluating the quality of the effects of medications, and if necessary replacing them, which ultimately leads to a better restoration of the structure and functions of the damaged spinal cord.

The method can be applied in practical resuscitation.

This method is used in the practice of the Department of Neuroanesthesiology and Resuscitation of the Municipal City Clinical Hospital No. 29 of Novokuznetsk.

Claims (1)

A method for the prevention of spinal cord ischemia by regulating hemodynamics in patients with spinal cord injury, including intensive therapy, characterized in that somatosensory evoked potentials (SSEPs) are recorded, the peak-to-peak interval N ₁₃ -N _{18 is} measured for spinal cord injury at the level of C ₁ -C ₂ vertebrae, N ₁₁ -N ₁₃ with damage at the level of C ₁ -C ₆ and N ₂₂ -C ₃₀ with damage at the level of C ₇ -L ₃ , then calculate the average blood pressure (SBP) and prescribe drugs that regulate the pressure, after which control p registration of SSEPs and with a decrease in the values of the inter-peak intervals, the selected drug and dosage are left unchanged, with a constant level of the inter-peak intervals, the dose of the drug is increased, and with an increase in the values of the intervals, therapy is intensified, increasing the dose or replacing the drug; SSEP indicators are evaluated after changing the dosage of the drug and in the dynamics of the study on days 3, 5, 9, as well as when the patient's condition worsens.