Intensive Care of Patients with COVID-19.

The severe course of COVID-19 requires treatment in emergency and intensive care units. Acute respiratory failure due to the development of pneumonia and acute respiratory distress syndrome is the most common and life-threatening manifestation of the new coronavirus infection. Treatment of patients with severe and extremely severe COVID-19; the use of modern schemes and protocols for drug therapy, mechanical ventilation, and extracorporeal membrane oxygenation; sorption techniques; the use of thermal helium; hemostasis correction; and rehabilitation problems are discussed.

[Endovascular treatment of acute ischemic stroke]. / Éndovaskuliarnoe lechenie ishemicheskogo insul'ta v ostrom periode.

Ischemic stroke is one of the leading causes of mortality and disability in the population of developed countries. Revascularization of the affected cerebral territory improves the prognosis and reduces mortality, which has been proven by randomized studies using systemic thrombolysis protocols. Over the last ten years, endovascular mechanical thrombus extraction using stent retrievers and/or aspiration neurointerventional catheters has been introduced into the clinical treatment of ischemic stroke, and after reporting the results of randomized studies on this topic, the technique has become ubiquitous. This work objective was to systematize the results of key studies on the treatment of acute ischemic stroke in chronological order, including the latest data of 2018.

[Topical respiratory strategies in neurocritical care]. / Aktual'nye respiratornye strategii v neiroreanimatologii.

Management of the respiratory tract and maintenance of adequate gas exchange are the basic goals of critical care. Injury to the nervous system is often accompanied by development of respiratory disorders. On the other hand, changes in the gas composition of arterial blood can cause brain damage. In addition, approaches to the patient with respiratory failure, which are used in general critical care and neurocritical care, may differ. The presented literature review is devoted to modern respiratory strategies used in neurocritical care.

[HYPOTHERMIA INFLUENCES ON OXYGEN TENSION IN THE BRAIN PARENCHYMA IN PATIENTS WITH ANEURYSMAL SUBARACHNOID HEMORRHAGE].

Aneurysmal subarachnoid hemorrhage is a serious medical and social problem. The main physiological mechanisms that determine secondary brain damage in this patients are intracranial hypertension, cerebral vasospasm, dysfunction of autoregulation mechanisms, violation of liquorodynamics and delayed cerebral ischemia. The multimodal neuromonitoring for prevention and timely correction ofsecondary brain injury factors has become routine practice in neuroICU. Measurement of oxygen tension in the brain parenchyma is one of neuromonitoring options. During the years of intensive use of this method in clinical practice the reasons for reducing the oxygen tension in the brain parenchyma were revealed, as well as developed and clinically validated algorithms for correction of such conditions. However, there are clinical situations that are difficult to interpret and even more difficult to make the right tactical and therapeutic solutions. We present the clinical observation of the patient with aneurysmal subarachnoid hemorrhage, who had dramatically reduced brain intraparenchymal oxygen pressure although prolonged hypothermia were used. Despite this, the outcome was favorable. The analysis allowed to assume that the reason for this decrease in oxygen tension in the brain parenchyma could be hypothermia itself

[AUTONOMIC NERVOUS SYSTEM AND ITS IMBALANCE IN NEURO INTENSIVE CARE UNIT].

The autonomic nervous system (ANS) provides homeostasis due to the innervation of the secretory glands, smooth muscle and cardiac muscle. Higher centers of the ANS (primarily the hypothalamus, some centers of the brain stem and limbic system) form a integrative network, which plays a key role in coordinating the functioning of the endocrine, immune system and other parts of the central nervous system. Intracranial centers of the ANS are responsible for the consciousness, behavioral, emotional, and other components of the higher nervous activity. Thus, the significance of the ANS can't be overestimated. At the same time today in neurointensive care there are no clear criteria for ANS dysfunction, we don't have universally recognized monitoring facilities for ANS and approaches to targeted therapy of its disorders. This paradox is even more important as in the pathogenesis of some critical conditions such as neurogenic pulmonary edema, stunned myocardium, cardiomyopathy Takotsubo lies precisely ANS imbalance. This review devoted to the ANS and some problems associated with its imbalance.

[SIMULTANEOUS MEASUREMENT OF INTRAVENTRICULAR AND PARENCHYMAL INTRACRANIAL PRESSURE IN PATIENTS WITH SEVERE TRAUMA BRAIN INJURY].

INTRODUCTION: "Standard" assessment of ICP by measuring liquor ventricular pressure recently questioned. THE OBJECTIVE OF THE STUDY: Compare the values of ventricular and parenchymal ICP against the closure of open liquor drainage and during active CSF drainage. MATERIALS AND METHODS: Examined 7 patients with TBI and intracranial hypertension syndrome, GCS 5.6 ± 1.2 points, 4.2 ± age 33 years. Compared parenchymal and ventricular ICP in three time periods: 1--during closure of ventricular drainage, 2--during of the open drains and drainage at the level of 14-15 mmHg, 3--during the period of active drainage. When comparing two methods of measurement used Bland-Altman method. RESULTS: 1. During time period of the closed drainage correlation coefficient was r = 0.83, p < 0.001. Bland-Altman method: the difference of the two measurements is equal to the minimum and 0.7 mm Hg, the standard deviation of 2.02 mm Hg 2. During time period of the open drainage was reduction of the correlation coefficient to r = 0.46, p < 0.01. Bland-Altman method: an increase in the difference of the two measurements to -0.84 mmHg, standard deviation 2.8 mm Hg 3. During time period of the active drainage of cerebrospinal fluid was marked difference between methods of measurement. Bland-Altman method: the difference was 8.64 mm Hg, and a standard deviation of 2.6 mm Hg. CONCLUSIONS: 1. During the closure of the ventricular drainage were good correlation between ventricular and parenchymal ICR 2. During open the liquor drainage correlation between the two methods of measuring the intracranial pressure is reduced. 3. During the active CSF drainage correlation between the two methods of measuring intracranial pressure can be completely lost. Under these conditions, CSF pressure is not correctly reflect the ICP 4. For an accurate and continuous measurement of intracranial pressure on the background of the active CSF drainage should be carried out simultaneous parenchymal ICP measurement.

[The rate of hyponatremia in neurosurgical patients (comparison between the data from the Burdenko Neurosurgical Instutite and the literature) and recommendations for the diagnosis and treatment].

UNLABELLED: Hyponatremia is a relatively frequent and serious complication in patients with various neurosurgical pathologies. OBJECTIVE: This study is aimed at assessing the incidence of hyponatremia in neurosurgical patients depending on the pathology. MATERIAL AND METHODS: This paper presents a retrospective analysis 39 479 cases of patients operated on at the Burdenko Neurosurgical Institute from 2008 to 2014. RESULTS: A total of 785 hyponatremic patients with Na level lower than 130 mmol/l (2% of all operated patients) were identified. Mortality in patients with hyponatremia was 14.3%, which is tenfold higher compared to the rest of population of patients without hyponatremia who were operated on during the same period. In adults, hyponatremia most frequently occurred after resection of craniopharyngiomas (11%) and as a result of acute cerebrovascular accident (22%). In children, it occurred after resection of craniopharyngiomas (10%), astrocytomas (7%), ependymomas (24%), and germ cell tumors (10.5%). CONCLUSION: This study, which was mainly statistical one, was not aimed at detailed investigation of hyponatremia in different groups of neurosurgical patients. We only tried to draw the attention of various experts to those categories of patients, where focused and in-depth developments are more than important. Obviously, already gained international experience should be taken into account for this PURPOSE: Therefore, this article presents the literature data on the etiology and pathogenesis of hyponatremia. We describe the details of the various classifications of hyponatremia, its clinical symptoms, diagnosis, and treatments, primarily based on the recommendations of the last European consensus of various specialists (2014).

[MASSIVE ARTERIAL BLEEDING FROM TRACHEOSTOMY: ANALYSIS OF TWO CASES].

In article described two cases of severe complication of tracheostomy - massive arterial bleedingfrom tracheal stoma. Both patients died. The causes of this complication, time of development and predictors of tracheo - arterial fistula formation, life-saving measures, and possible surgical treatment discussed.

[PrÑ -monitoring based decision-making about decompressive craniectomy in a patient with severe traumatic brain injury. A case report].

The presented case illustrates a new approach to making a decision about decompressive craniectomy in the patient with sever traumatic brain injury and intracranial hypertension. The approach is based on continuous assessment of cerebral autoregulation using Prx-monitoring in addition to monitoring of intracranial pressure and cerebral perfusion pressure. Prx-monitoring enables timely detection of autoregulation failure and provides the opportunity to make a decision about decompressive craniectomy before starting such aggressive methods of intensive care as hypothermia or barbiturate coma.

[The use of intravascular hypothermia to correct intracranial hypertension in patients with severe traumatic brain injury].

OBJECTIVE: Assess to impact hypothermia on ABP, CPP, ICP and cerebral autoregulation. Material and methods. 14 patients with TBI (GOS<9) underwent hypothermia by Thermogard system within 32-35 °C (Zoll, USA). ICP was measured intraparenchymal by Codman sensor. Cerebral autoregulation was estimated by correlation coefficient Prx (Soft ICM Plus, Cambridge, UK). Temperature was measured in urinary bladder. There were selected five time periods: 1 - phase of initial state, 2 - phase of induction hypothermia, 3 - phase of hypothermia, 4 - phase of rewarming, 5 - phase after finishing hypothermia. All data preset as Mediana (min; max). Stat analysis was perfomed using Soft Statistica 10.0. Results. Phase 1 lasted nearly 7 (2; 12) h, ABP 94 (81; 102), CPP - 73 (52; 87), ICP 27 (16; 45) mm Hg, Prx 0,25 (-0,15; 0,7), temperature 38,2 °C (37; 39,8). Phase 2: 5 (2; 12) h, ABP 95 (85; 114), CPP 80 (65; 96), ICP 18 (10; 22) mm Hg, Prx -0,055 (-0,15; 0,7), temperature 35,2 °C (34,5; 35,5). Phase 3: 55 (20; 100) h, there were not significant changed ABP, CPP, Prx, ICP 15 (10; 18) mm Hg, temperature was 33,5 °C (32; 34,7). Phase 4: 17 (8; 24) h, ABP 90 (70; 100), CPP 77 (55; 85), ICP 15 (9; 27) mm Hg and Prx 0,2 (-0,2; 0,32). Temperature 36,9 °C (35,9; 38,5). Phase 5: 20 (6; 240) h, ABP 87(53; 110), CPP 72 (47; 107), ICP 17 (10; 32) mm Hg and Prx 0,2 (-0,2; 0,6). Temperature 37,7 °C (36,7; 39,0). Conclusion. Hypothermia is an effective method for correction of intracranial hypertension. Hypothermia can use as a additional option of intensive care during refractory intracranial hypertension. Rewarming phase is the most dangerous time on the re-development of intracranial hypertension and disruption of autoregulation.

[Risk factors of postoperative meningitis in patients with chiasm-sellar tumors].

UNLABELLED: Postoperative intracranial infectious complications are one of the most topical problems of neurosurgical intensive care due to theirs significant capability to impair outcomes of the main disease. PURPOSE OF THE STUDY: To define the risk factors of postoperative meningitis in patients with chiasm-sellar tumors. RESEARCH OBJECTIVES: 1. to define the effect of somatic and intracranial risk factors on occurrence of postoperative meningitis in patients after transsphenoidal and transcranial approaches to the tumor. 2. To define the effect of postoperative meningitis on outcomes of treatment in patients after transsphenoidal and transcranial approaches to the tumor. MATERIALS AND METHODS: Somatic and intracranial risk factors of occurrence of postoperative meningitis (pneumonia, urinary tract infection, sepsis, intra-abdominal hypertension, the presence of external ventricular and lumbar drainage, monitoring of intracranial pressure, cerebrospinal fluid, and reoperation) were fixed every day. The study was conducted in the ICU of the Burdenko from October, 2010 to July, 2012. The 34 patients (19 males, 15 females) were included in the study (average age 47.5 years). The patients were divided into two groups; 17 patients each group. The group-1 included patients after transcranial approach to the tumor and the group-2 included patients after transsphenoidal approach. RESULTS: In the group-1 a meningitis occurred in 3 patients (17.6% +/- 9.2%, DI [-0.4 - 35.6]). In the group-2 a meningitis occurred in 7 patients (41.2% +/- 11.9) DI 95% [17.8 - 64.4]. Accumulation of cerebrospinal fluid under the skin flap authentically increased a risk of a meningitis occurrence in patients after transcranial approach to the tumor (p = 0.031). There was no defined statistical significance of other risk factors. But there was defined a trend of the increasing of meningitis occurrence in patients after transsphenoidal approach in case of lumbar drainage or reoperation. Duration of mechanical ventilation and ICU stay in patients with meningitis was authentically longer than in patients without meningitis in both groups. In the group-2 the duration of mechanical ventilation and ICU stay was significantly shorter than in the group-1. CONCLUSIONS: Meningitis is not a typical complication of postoperative period in patients with transcranial approach to the tumor. After transsphenoidal approach a meningitis occurrence is likely in case of postoperative liquorrhea, lumbar drainage or reoperation. Subcutaneous accumulation of cerebrospinal fluid is a single defined statistically significant risk factor of meningitis. Postoperative meningitis impairs a condition of patients with chiasm-sellar tumors, increases the duration of mechanical ventilation and impairs treatment outcomes.

[Possibilities of using intravenous forms of antiepileptic drugs in epileptic seizures]. / Vozmozhnosti primeneniia vnutrivennykh form protivoépilepticheskikh preparatov pri épilepticheskikh pristupakh.

The literature data on using intravenous forms of AEDs that expand treatment possibilities for patients with epilepsy are presented. AEDs can be used in different situations, when patients are not able to take AEDs in per os. These situations can include seizure emergencies (recurrent seizures, clusters, status epilepticus), caused by disease decompensation; acute symptomatic seizures; perioperative preparation in the case of surgery; dysphagia; gastrointestinal problems; psychiatric disorders, and others. This article is based on a review of International and Russian expert consensus practice guidelines for management of clinical situations mentioned above. The authors present data on available Russian parenteral forms of drugs used today (valproats, levetiracetam, lacosamide, diazepam, midazolam, propofol, thiopental potassium). It has been concluded that an ideal intravenous AED should be highly effective, acts fast, has no severe adverse effects, has low drug-drug interactions, does not require frequent plasma concentration monitoring, and should be easily switched to a per os form without any additional titration. The importance of separate treatment approaches on different stages of medical help is emphasized. The choice of drug used can be influenced by a particular clinical situation, indications/contraindications, the recommended infusion speed, side effects, possible drug-drug interactions with other AEDs and other drugs used for the treatment of concomitant diseases, availability of a particular drug at the moment and the level of a physician's knowledge of usage of intravenous forms of AEDs.

[Citicoline as component of the therapy of postoperative delirium in neurosurgical patients].

Delirium is a clinical sign of acute cerebral dysfunction. It is characterized by consciousness alterations with attention impairment and mentally disorganization. Frequency of delirium is 40-80% in general intensive care and more in patients in neurointensive care unit. We tried to assess citicoline (Ceraxon, Nycomed) safety and efficacy in treatment of postoperative delirium in patients with tumors of chiasm-sellar area of brain. 12 patients were included in citicoline group and 8--in control group. In both group combined type of delirium was common: 83.3% and 75%, accordingly. Citicoline didn't influence on delirium duration. Median of duration of mechanical ventilation was 1.5 and 6 days; mean and standard deviation were 10.5 +/- 15.4 and 17.5 +/- 27.9 days. Median of length of stay in ICU was 7 and 9.5 days; mean and standard deviation were 25.4 +/- 33.1 and 14.9 +/- 15.1 days. These results show that citicoline didn't influence on duration of mechanical ventilation and length of stay in ICU. Outcomes were similar in both groups, but frequency of full functional state recovery in citicoline group was significantly higher: 5 (41.7%) to 2 (25%) in control group (p < 0.05). We consider that citicoline therapy is safe for patients with tumors of chiasm-sellar area and lead to increasing of frequency of full functional state recovery.

[Intracranial pressure plateau waves in patients with severe traumatic brain injury].

The goal of the study was to assess frequency of plato waves, their influence on outcomes and define factors leading to plato waves. Ninety eight patients with severe traumatic brain injury (TBI) were included. Blood pressure (BP), intracranial pressure (ICP), cerebral perfusion pressure (CPP) and pressure reactivity index (Prx) were registered. Age was 34 +/- 13.6. There were 73 male and 25 female. Glasgow Coma Scale (GCS) was 6 +/- 1.4. Plato waves developed in 24 patients (group 1), 74 patients (group 2) did not have plato waves. Median of plato waves in the 1st group was 7[3.5; 7]. They developed on 3rd [2;4.5] day. Maximum level of ICP during plato waves was 47.5 [40;53] mmHg, its duration was 8.5 [7;27] minutes. In the group 1 Prx was significantly lower during first day, than in the group 2. Duration of ICP monitoring was longer in the group I due to presence of plato waves in these patients. CPP did not differ in groups, because CPP was strictly controlled. Patients of the group I had preserved autoregulation and less severe trauma (predominance of closed trauma and Marshall I, II type of brain damage). Plato waves did not predict bad outcomes.

[Endoscopic endonasal anterior extended transsphenoidal approach in craniopharyngioma surgery].

The paper describes results of treatment of 56 patients with suprasellar craniopharyngioma (stem, intra-extraventricular) who were operated in Burdenko Neurosurgical Institute using endoscopic endonasal anterior extended transsphenoidal approach. Assessed dynamics of major clinical syndromes (neuro-ophthalmological symptoms, neurological and hormonal status), radicality of surgery, incidence and nature of postoperative complications, postoperative mortality. A comparative analysis of the results obtained in previous studies of our Institute, as well as with those of foreign authors is performed. Obtained data show that endoscopic endonasal anterior extended transsphenoidal approach in craniopharyngioma surgery is an efficient and non-traumatic technique, capable of providing a radical removal of the tumor along with a high quality of life after surgery, and relatively low rates of postoperative complications and mortality.

[Damage to the cavernous segment of internal carotid artery in transsphenoidal endoscopic removal of pituitary adenomas (report of 4 cases)].

Endoscopic endonasal transsphenoidal approach (EETA) is an effective and relatively safe to remove pituitary adenomas and other sellar region tumors. One of the most serious complications of transsphenoidal surgery is damage to the cavernous segment of the internal carotid artery, which by different authors occurs at 0 to 3.8%. In the period from 2005 to March 2013 in Burdenko neurosurgical institute 3,000 patients with pituitary adenomas were operated by standard endoscopic transsphenoidal approach. Damage to the internal carotid artery (ICA) occurred in 4 patients, which amounted to 0.13%. To all patients with damage of the ICA angiography was performed in which identified one case of occlusion of the ICA and three cases of false aneurysm formation. Three patients underwent endovascular treatment. Damage to the internal carotid artery may be associated with the wrong orientation in the surgical wound, or excessively aggressive manipulations in the cavernous sinus. Damage to the cavernous segment of the ICA during transsphenoidal surgery is a rare but potentially fatal complication. Extremely important is the correct localization of the middle line and ICA using navigation systems and Doppler ultrasound.

[Analysis of thyroid homeostasis disorders in patients with severe traumatic brain injury].

Aim of the study was to investigate the status of thyroid homeostasis and the relationship between severe traumatic brain injury (TBI) and thyroid disorders. The study included 56 patients. Protocol of the study concluded: noninvasive and invasive hemodynamic monitoring, including PICCO, transcranial Doppler ultrasonography, measurement of intracranial pressure (ICP), indirect calorimetry, levels of thyroid stimulating hormone (TSH), T3, T4 and free fractions. Patients were divided into three groups. Group 1--with normal thyroid hormones (n = 20), Group 2--with the low T3 (n = 23) and Group 3 with the low T3 and T4 (n = 13). Correlation between the Glasgow Coma Scale (GCS) and thyroid hormone levels was obtained: the first group between GCS and T4 (r = 0.50), GCS, and free fraction T4 (r = 0.51); between the GCS and TSH (r = 0.51), T3 (r = 0.48) and T4 (r = 0.57) in the second group, and the third--with TSH (r = 0.67). Poor outcomes in the first group compound 15%, in the second group--39.2%, and in the third group--62.5% of patients. Doses of vasopressors were significantly higher in groups 2 and 3 compared with a first group. ICP was significantly higher in the group with the low T3 and T4. Development of intracranial hypertension correlated with the formation of thyroid insufficiency. Deficiency of thyroid hormones, especially the simultaneous reduction and T3, and T4 is associated with poor outcome in patients with severe TBI. Doses of sympathomimetic drugs used to optimize the parameters of systemic hemodynamics in acute severe head injury were higher in patients with deficiency of thyroid hormones.

[Optimizing blood pressure in patients with sellar region tumors during complicated postoperative period].

Mechanism of arterial hypotension (AH) in patients with sellar region tumors (SRT) and complicated postoperative period consists in decrease of systemic vascular resistance and relative hypovolemia. Therapeutic directions for blood pressure (BP) stabilization are clear. However criteria of optimal BP in these patients are absent. Object of the study was defining such criteria. Prospective study was conducted from January, 2011 to January, 2012. Inclusion criteria were: adults; SRT; early postoperative period. Thirty patients were included into the study. Patients were divided into three groups. Group I (n=11) consisted of patients with uncomplicated postoperative period; group II (n=12) - patients with complicated postoperative and with stable hemodynamics; group III (n=7) - patients with complicated postoperative period and AH. Median of central venous saturation (ScvO2) was normal in all groups. ScvO2 was significantly higher than jugular vein saturation (SjvO2) in all measurement. In group I SjvO2 was normal, and it was higher, than in group II. In group SjvO2 did not achieve normal level during three days of the study. Mean BP did not change during these days. In group III SjvO2 was decreased if mean BP was between 70 and 90 mmHg. This level of SjvO2 did not differ from SjvO2 in group II. When mean BP increased up to 100-110 mmHg SjvO2 significantly increased too in the group III and achieved level of the group I (normal level). Outcomes were favorable in all patients of the group I (GOS=4, 5). Median of length of stay (LOS) in the ICU was 1 day. In group II outcomes were favorable in 10 (83.3%) patients, 2 (16.7%) patients died. Median LOS in ICU was 7 days. In group III outcomes were favorable in 6 (85.7%) patients, unfavorable outcome (GOS=3) was in 1 (24.3%) patient. Median LOS in ICU was 12 days. There were no significant differences in all groups in the lactate levels both in central vein and in jugular vein. ScvO2 can not be a criterion for BP optimization in patients with SRT. In patients with uncomplicated postoperative period SjvO2 is normal. In patients with complicated postoperative period and normal BP SjvO2 remains decreased. In patients with complicated postoperative period and arterial hypotension normal level of SjvO2 can be achieved if mean BP is increased up to 100-110 mmHg. SjvO2 normalization can improve outcomes in patients with SRT and complicated postoperative period.

[First experience of using adaptive support ventilation (ASV) mode in patients with severe traumatic brain injury].

Capabilities and limitations of ASV mode in TBI patients are studied. 12 patients with severe TBI were enrolled in the study. ICP, MAP, CPP were monitored in all the patients. Cerebral regional blood flow was monitored by thermal diffusion in four patients. Hamilton G5 ventilator was used for mechanical ventilation and respiratory monitoring in all cases. Starting mode of mechanical ventilation was ASV with 100% mechanical substitution. The patient was regarded as ASV-nonresponder and switched to another mode when normoventilation was not possible with any percent of respiratory substitution. ASV mode provided normoventilation during all period of mechanical ventilation in 88 ou of 12 patients. In 4 out of 12 patients ASV mode led to hyperventilation with EtC02 decrease, cerebral regional blood flow slowing and P0,1 index increase. In three patients hyperventilation was induced by high rate of spontaneous breaths caused by brainstem irritation. Switching these patients to SIMV-VC led to normoventilation, normalization of etC02 and cerebral regional blood flow, and P0,1 index decrease. In one patient hyperventilation was caused by lung mechanics disorder when ventilator tried to achieve target minute volume by low tidal volume and high respiratory rate. ASV mode provides adequate lung ventilation during respiratory support period in most patients with severe TBI. It can prove ineffective for some patients with brainstem irritation or lung mechanics disorders.

[Using ASV mode for respiratory support withdrawal in patients after posterior fossa surgery].

The study gives data on how to improve the way from mechanical to spontaneous breathing in patients with weakened respiratory drive after posterior fossa tumor removal. We compared the effectiveness of two methods of weaning from mechanical ventilation in these patients. The main group consisted of 6 patients weaned from ventilator with ASV mode. The control group was made up of 10 patients weaned from ventilator with SIMV or PS modes. The duration of weaning from ventilator using ASV mode was significantly shorter than with SIMV or PS modes. During ASV ventilation spontaneous breath rate gradually increased. In all patients the level of P0,1 index representing respiratory center activity was initially lower than normal. While spontaneous breath activity increased the level of P0,1 index also gradually normalized. Plmax index (respiratory effort index) measured once a day increased as well. Weakened respiratory drive is accompanied by P0,1 and Plmax indexes' decrease in patients after posterior fossa tumor removal. ASV mode in these patients allows quicker weaning from mechanical ventilation.