Chronic respiratory insufficiency – the secondary syndrome arising at inability of respiratory system to support a gas homeostasis that leads to decrease in Rao2 and increase in RASO2 in arterial blood. Develops for a number of years; it is shown by signs (short wind), gipoksemiya and giperkapniya (cyanosis, tachycardia, effects from TsNS), weakness of respiratory muscles (change of ChD, participation of auxiliary muscles). The analysis of gases of blood, the FVD tests, a pulsoksimetriya helps to estimate degree of chronic respiratory insufficiency. Therapy includes correction of causal factors, purpose of bronchodilators, mukoregulyator, long O2 therapy. In an individual order the issue of transplantation of lungs is resolved.
Chronic respiratory insufficiency
The Chronic Respiratory Insufficiency (CRI) – the simptomokompleks caused by impossibility of system of breath to provide an adequate ratio of gases of arterial blood. It is characterized by gradual development against the background of progressing of the main disease. At exacerbations prichinno of significant pathology can get signs of sharp respiratory insufficiency. According to indicative data, the number of the people suffering from chronic respiratory insufficiency and demanding performing long oxygenotherapy or house ventilation of lungs in economically developed countries makes 0,08-0,1%. The following features are characteristic of HDN: development within several months or years; the gradual beginning and the progressing current. The solution of the clinical questions connected with chronic respiratory insufficiency is, mainly, in competence of pulmonology and resuscitation.
As the most frequent causal factors causing emergence of chronic respiratory insufficiency serve bronchopulmonary diseases. Bronkhiolita, bronchitis of the smoker and other forms of chronic bronchitis, a bronkhoektatichesky disease, bronchial asthma, HOBL, interstitsialny pulmonary diseases, tuberculosis, , emphysema, a pneumosclerosis, etc. concern to them obstructive a dream. At late stages pulmonary hypertensia is followed by signs of respiratory insufficiency.
Can lead the thorax diseases limiting breath depth to HDN (, , torakoplastika consequences, obesity and so forth). Among other things, chronic respiratory insufficiency can be a consequence of defeat of the neuromuscular device at muscular dystrophy of Dyushenn, the BASS, poliomyelitis, diaphragm paralysis, spinal injuries. Anemia, congenital heart diseases, a hypothyroidism, incomplete restoration after ODN episode are also among the possible reasons of HDN.
Thus, act as the main pathophysiological mechanisms of formation of chronic respiratory insufficiency alveolar hypoventilation, ventilating an imbalance, violation of diffusion of gases through an alveolar and capillary membrane. Development of a giperkapniya and gipoksemiya in response to which the organism starts a number of the compensatory reactions designed to provide O2 transport to fabrics is a consequence of these processes. From cardiovascular system tachycardia and increase in warm emission is noted. In response to an alveolar hypoxia there is a pulmonary vazokonstriktion which is followed by improvement ventilating the relations. Develops in blood , increasing the oxygen capacity of blood. However along with positive effects, compensatory mechanisms play also a negative role. All listed adaptive reactions lead to formation of pulmonary hypertensia, pulmonary heart and heart failure over time.
Classification of HDN
Taking into account distinctions of pathogenesis distinguish HDN of two types: gipoksemichesky (pulmonary, parenchymatous, type DN I) and giperkapnichesky (ventilating, type DN II). As criteria of DN I of type serve a gipoksemiya in combination with hypo - or a normokapniya. This type of chronic respiratory insufficiency is formed against the background of the diseases which are followed by defeat of a pulmonary parenchyma (alveolit, a pneumoconiosis, a sarkoidoz of lungs, etc.). DN II of type is characterized by a giperkapniya and a gipoksemiya (the last well gives in to oxygenotherapy). As the reasons of ventilating respiratory insufficiency HOBL, damage of respiratory muscles, decrease of the activity of the respiratory center, etc. can act.
As violation of external breath chronic respiratory insufficiency is classified on obstructive, restrictive and mixed. At an obstructive form decrease in an index of Tiffno, stream values, increase in bronchial resistance and pulmonary volumes takes place. Decrease in ZhYoL is characteristic of a restrictive syndrome
Severity of chronic respiratory insufficiency is estimated, proceeding from gas-metric indicators:
- HDN I of the Art. - RASO2 70 mm hg.
- HDN II of the Art. - RASO2 50-70 mm hg; Rao2 70-50 mm hg.
- HDN III of the Art. - RASO2> 70 mm hg, Rao2
The Giperkapnichesky coma comes at increase in RASO2 to 90-130 mm hg, a gipokapnichesky coma – at decrease in Rao2 till 39-30 hg.
The clinical course of chronic respiratory insufficiency depends on the main pathology, type and weight of DN. As its most typical manifestations serve , effects of a gipoksemii/giperkapniya and dysfunction of respiratory muscles.
Short wind acts as the earliest and universal symptom of HDN , or. Subjectively it is perceived by patients as feeling of shortage of air, discomfort at breath, need to make respiratory effort and so forth. At obstructive DN short wind has expiratory character (the exhalation is complicated), at restrictive – inspiratory (the breath is complicated). Short wind at physical efforts for many years can be the only sign to chronic respiratory insufficiency.
The main clinical sign indicating a gipoksemiya is cyanosis. Its expressiveness and prevalence testifies to weight of chronic respiratory insufficiency. So, if in the subcompensated stage at patients only cyanosis of lips and nail beds is noted, then in a decompensation stage it accepts widespread, and in a terminal stage – generalized character. Haemo dynamic changes at a gipoksemiya include tachycardia, arterial hypotonia. At decrease in Rao2 to 30 mm of mercury. there are sinkopalny episodes.
Giperkapniya at chronic respiratory insufficiency is followed by increase in ChSS, violations of activity of TsNS (night sleeplessness and day drowsiness, headaches). Act as symptoms of dysfunction of respiratory muscles change of ChD and respiratory pattern. In most cases chronic respiratory insufficiency is followed by breath increase (). Decrease in ChD to 12 in min. serves as the terrible harbinger indicating a possibility of respiratory standstill less. Treat the changed stereotypes of breath involvement of additional groups of the muscles which normal are not involved in breath (inflating of wings of a nose, tension of muscles of a neck, participation in an exhalation of belly muscles), paradoxical breath, a torakoabdominalny asinkhroniya.
Clinical classification of respiratory insufficiency provides allocation of four of its stages.
- I (initial) – carries the hidden current, masking symptoms of the main disease. Feelings of shortage air and increase of breath arise at physical efforts.
- II (subcompensated) – short wind arises at rest, the patient constantly complains of shortage of air, has feeling of concern and alarm. Additional muscles are involved in the act of breath, cyanosis of lips and finger-tips takes place.
- III (dekompensirovanny) – short wind is sharply expressed and forces the patient to adopt the compelled provision. Auxiliary muscles participate in breath, widespread cyanosis, psychomotor excitement is noted.
- IV (terminal) – is characterized by the consciousness oppression poured by cyanosis, superficial arrhythmic breath, bradycardia, arterial hypotension, an oligoanuriya. Can pass into a gipoksemichesky or giperkapnichesky coma.
Diagnostics of HDN
The algorithm of inspection of patients with chronic respiratory insufficiency assumes assessment of the fizikalny status, a research of laboratory indicators of blood and respiratory mechanics. In all cases patients have to be examined by the pulmonologist (if necessary other experts: therapist, cardiologist, neurologist etc.) regarding detection of the main disease. For assessment of changes in pulmonary fabric the X-ray analysis of lungs is carried out.
The analysis of gas composition of blood allows to estimate HDN degree on the basis of the major indicators: Rao2 RASO2, and level of bicarbonates. The large role is played by a dynamic research of gases of arterial blood, and not only in the afternoon, but also at night. For noninvasive measurement of saturation of arterial blood oxygen (SpO2) uses a pulsoksimetriya.
For the purpose of assessment of weight and the HDN type, monitoring of a condition of the patient the FVD tests are carried out (measurement of ZhYoL, POS of the forced exhalation, Tiffno's index, FASHION, etc.). To estimate function of respiratory muscles, measurement of inspiratory and expiratory pressure in an oral cavity is performed. Additional characteristics can be received when carrying out a polisomnografiya.
Treatment of HDN
Therapy of chronic respiratory insufficiency includes simultaneous work in several directions. One of them is a correction prichinno of significant factors, i.e. impact on primary disease. In out-patient conditions treatment appoints and the profile expert (the pulmonologist, the phthisiatrician, the pathologist, the therapist) controls. Hospitalization of patients with chronic respiratory insufficiency is carried out only in case of an exacerbation of the main pathology or at DN decompensation. Adequate etiotropny therapy can constrain a long time progressing of HDN and even to lead to reduction of its expressiveness.
As the bronkhoobstruktion often is the cornerstone of chronic respiratory insufficiency, bronchial spasmolytics (, salbutamol, ), mukoregulyator are widely applied (Ambroxol, ). With care it is necessary to treat appointment of somnolent and sedative medicines as such patient as they can reduce activity of the respiratory center. Work in the direction of respiratory rehabilitation assumes occupations physiotherapy exercises with inclusion of breathing exercises, vibration and perkutorny massage of a thorax, halotherapy, physical therapy.
The chronic respiratory insufficiency which is followed by a resistant gipoksemiya is the basis for application of a long kislorodoterapiya (DKT). The procedure assumes inhalation of the gas mix containing to 95% of oxygen for 15-18 and more hours a day. Duration of a course of a kislorodoterapiya is defined on the basis of indicators of a saturation of blood and partial pressure of oxygen. DKT allows to increase efficiency of pharmacotherapy and physical efficiency of patients, to reduce number of hospitalization, to increase life expectancy of patients with HDN for 5-10 years. DKT can be carried out even in house conditions by means of portable sources of oxygen.
SIPAP-terapiya (IVL constant positive pressure) finds application for therapy of patients with the chronic respiratory insufficiency caused by a trakheomalyation, a syndrome sleepy as prevents fall of airways. Patients with the accruing giperkapniya need carrying out the long house ventilation of lungs (HVL) which can be both noninvasive (mask), and invasive (through a tracheostoma). At HDN caused by HOBL, mukovistsidozy lungs, interstitsialny pulmonary fibrosis, etc. the issue of expediency of transplantation of lungs is resolved.
The long-term forecast at chronic respiratory insufficiency unsatisfactory. At decrease in Rao2 to 60 mm of mercury. survival of patients makes about 3 years. Timely and rational therapy of HDN can improve the forecast. Scheduled maintenance comes down to the prevention and prevention of the complicated course of primary diseases.