Our Success in the Treatment of Acute Respiratory Failure in Coronovirus Patients Using Non-invasive Ventilation

The novel coronavirus infection (COVID-19) pandemic, caused by the highly contagious severe acute respiratory syndrome coronavirus (SARS-CoV-2), is still at its peak, causing thousands of deaths every week. Since the beginning of the coronavirus (just a few months ago), our understanding of the disease has grown rapidly. While there are several large, randomized drug trials currently underway, current survival from severe COVID-19 is entirely dependent on providing the best supportive care possible.


Introduction
For patients with acute respiratory failure with suspected COVID-19 or with confirmed COVID-19, the strategy and tactics of respiratory therapy and respiratory support do not differ significantly from those for parenchymal acute respiratory failure of any genesis (community-acquired bacterial or viral pneumonia, nosocomial, including respirator-associated pneumonia, ARDS) [1,2]. The strategy and tactics of choosing methods of respiratory support and correction of parameters of mechanical ventilation in severe acute respiratory failure caused by a new viral infection COVID-19 is, in principle, similar to those in ARDS caused by direct damaging factors [3][4][5][6]. The basic principles of the effectiveness of treatment of severe parenchymal acute respiratory failure of various origins are as follows: a. timely differential diagnosis of acute respiratory failure.   [1,2,4,5,7,8].
Considering that acute respiratory failure in ARDS and viral pneumonia has similar fundamental mechanisms of pathogenesis (decrease in thoracopulmonary compliance, decrease in functional residual capacity, accumulation of extravascular fluid in the lungs, deterioration of regional ventilation-perfusion relations and an increase in intrapulmonary shunting of blood), in the case of hypoxemia it appears it is inappropriate to carry out traditional oxygen therapy (through nasal cannulas or a face mask) [9].
Indeed, the use of a low-flow (4 -8 l/min) air-oxygen mixture will not allow to effectively influence the basic mechanisms of Hg Art. and / or its progressive increase; hypocapnia -PaCO 2 <7.35 and / or its progressive decrease; increased airway resistance (Raw) is 1.5-2.0 times higher than normal; tachycardia at rest (heart rate> 90 per minute); arterial hypertension (hypotension), acrocyanosis, cyanosis, a combination of the above factors [10,7,11]. Modern respiratory technologies make it possible to implement various modes of respiratory support in NIV conditions with a wide range of settings for ventilation parameters in patients of different profiles.
In several clinical situations, NIV is an effective alternative to mechanical ventilation. The advantages of NIV over mechanical ventilation:

absence of complications inherent in tracheal intubation
and long-term presence of an endotracheal tube in it.

2.
lower risks of developing respiratory complications.
3. lower risks of developing circulatory complications.

4.
reducing the risks of developing nosocomial infections.

5.
reducing the need for medication sedation. improving cardio hemodynamics, reducing the load on the right ventricle of the heart; maintaining the cough reflex -reducing the risk of developing respirator-associated pneumonia; facilitating the process of weaning from mechanical ventilation; reduction in the duration of respiratory support and stay in the intensive care unit [6,11,13]. However, any NIV method is not devoid of negative effects.
The main disadvantages of NIV: 1) the need for active cooperation of medical personnel with the patient.
2) the complexity of setting the NIV parameters.
3) the need for frequent correction of NIV parameter settings.

Objective
To determine the benefits of NIV in ARF in patients with

Research Material
The study included 25 patients admitted to the intensive care unit of the AMU surgical clinic during the period from April 1 to August 1, 2020.

Research Results
Our experience with NIV has shown that most patients undergoing NIV tolerate this procedure relatively well at the initial It should be borne in mind: i. high values of PEEP (10-12 cm of water column and more) and/or PS 16-18 cm of water. Art. and more), despite a temporary improvement in oxygenation, lead to patient discomfort and increase the risk of developing lung damage.
ii. dyspnea reduction is usually achieved shortly after adequate ventilation has been set, while hypercapnia and/or hypoxemia may take several hours to correct.
iii. during the first hours, the NIV should be carried out e. an increase in the ratio of respiratory rate/tidal volume >100.
f. the emergence or growth of encephalopathy.
g. desynchronization of the patient with the respirator.
h. appearance or increase of acidosis.
i. deterioration of the patient's condition.
The criterion for successful NIV in our study was the improvement of arterial blood gas composition and the ability to avoid endotracheal intubation.   (Figures 1-9).