The Air Leak Syndrome (ALS) — group of the morbid conditions which are characterized by a gas congestion out of alveolar space.
Most often disturbance of integrity of alveoluses results from damage of a respiratory epithelium of alveoluses and terminal pneumatic ways by high intra pulmonary pressure.
SUV nosological forms:
- intersticial pulmonary emphysema;
- pheumothorax;
- pneumomediastinum;
- pneumopericardium;
- pneumoperitoneum;
- hypodermic emphysema.
Listed to a nosology can arise separately or in a combination with each other. Lethality in group of children with SUV at different forms reaches 50%. At the survived children the frequency of development of chronic pathology of easy and heavy neurologic frustration, as a result of intracraneal hemorrhages is high.
Intersticial pulmonary emphysema
At development of the intersticial pulmonary emphysema (IPE) air through the damaged alveolar epithelium gets into intersticial space of lungs. Most often IEL meets at premature children with body weight less than 1000. Refer to risk factors:
- respiratory distress syndrome;
- morfofunktsionalny immaturity of lungs;
- aspiration syndrome;
- congenital pneumonia;
- disposition of an endotracheal tube (one-lung ventilation).
At ILE ruptures of an epithelium of alveoluses and small airways lead to a congestion of vials of gas in intersticial space of pulmonary fabric. Intersticial gas becomes the reason of a mechanical compression of alveoluses up to their atelektazirovaniye that leads to decrease in extensibility of lungs and disturbance of the ventilating and perfusion relations. Shunting of blood on "idle" alveoluses and a mechanical prelum of vessels intersticial gas leads to increase in pulmonary pressure and development of secondary pulmonary hypertensia. The described pathological process leads to need of increase in parameters of ventilation that, in fact, closes ILE pathogeny "vicious circle".
The diagnosis of ILE is made on the basis of clinical, radiological and datas of laboratory. Sometimes ILE is diagnosed after drainage of pheumothorax and a raspravleniye of an affected lung. In most cases, identification of ILE is preceded by an aggravation of symptoms of the child, decrease in oxygenation, need of increase in the IVL parameters, desynchronization with hardware ventilation, a tendency to arterial hypotension. At objective survey at the child thorax swelling, crepitant rattles on the party of defeat can be observed. Laboratory the hypercapnia, an anoxemia and acidosis come to light. A classical X-ray analysis of a thorax in a direct projection lying allows to diagnose accurately ILE which is shown in two main forms: linear and kistoznopodobny. Often these two forms come to light together. Linear ILE is visualized as unbranched shadows from 3 to 8 mm long, width them seldom exceeds 2 mm. The Kistoznopodobny form represents roundish, sometimes oval, shadows from 1 to 4 mm in the diameter. Sometimes this X-ray pattern is mistakenly interpreted as normally aerated lung surrounded with exudate as at an aspiration syndrome or a fluid lungs. The linear form needs to be differentiated from "air bronkhogramm" at RDS. "Air bronkhogramma" represent the extended branched shadows reminding a tracheobronchial tree, gradually decreasing and disappearing to the periphery. The ILE linear form is visible in distal departments of lungs, away from bronchial tubes and has no branches.
ILE should be differentiated with congenital cystous anomalies (lobar emphysema, kistoadenomatoz) and a hyperinflation of lungs.
One of methods of treatment is therapy by situation. The child keeps within sideways on the party of defeat. At the same time a certain compression of respiratory tracts from the struck party and vice versa, increase in ventilation and oxygenation in conditionally healthy lung is reached. An integral part of this technique — gradual decrease in parameters of ventilation. Peak and average pressure in respiratory tracts have to be reduced to the minimum allowing to support acceptable blood gases: PaO2 35–55 mm Hg., PaCO2 up to 65 mm Hg., pH more than 7.2. For ensuring target oxygenation after decrease in PIP it is possible to increase FiO2. The strategy of restriction of respiratory volume provides its gradual decrease against the background of synchronized ventilation to potentially safe values — 4–6 ml/kg. For minimization of a barotrauma and a volyumotravma recommend to use the modes of trigger ventilation: SIMV, A/S, PRVC. At development of ILE transfer of the patient to VChO IVL is shown, the probability of formation of air traps thereby decreases, the uniformity of ventilation, the maximum raspravleniye of atelektazirovanny sites of lungs is reached and excessive pressure in the reinflated alveoluses decreases.
The selective bronchial intubation declared by some authors as a treatment method at ILE at newborns is technically exigeant at damage of the right lung while SUV in 2/3 cases is noted exactly on the right.
Mortality connected with ILE reaches 67% at the children who are on IVL. Early identification (till 48 o'clock after the birth) increases this figure to 100% as directly correlates with weight of parenchymatous damage of lungs. Complications of ILE are others a type of SUV, an air embolism, chronic pulmonary diseases, intraventricular hemorrhages, a pereventrikulyarny leykomalyation. The main methods of prevention of ILE are: implementation of clinical recommendations and protocols about the basic help and primary resuscitation in the patrimonial hall, on maintaining children with RDS.
Pheumothorax is a type of SUV at which air gets into a pleural cavity owing to disturbance of integrity of a visceral pleura.
Spontaneous not tension pneumothorax as result of restretching and rupture of alveoluses because of strong increase in intra pulmonary pressure meet at 1% of newborns during the first several breaths.
It is possible to suspect spontaneous pheumothorax at the newborn on the following symptoms: a tachypnea, increase in a thorax in a perednezadny size, asymmetry of a thorax, weakening of breath, a bandbox shade of a sound on side of the affected lung, the percussion shift of borders is cardiac dullness, a priglushennost of warm tones. As a rule, such pheumothoraxes are stopped independently, but demand intensive observation of the patient. The greatest danger is represented by a tension pneumothorax with the expressed lung compression on the party of defeat and mediastinum shift in the healthy party. The diseases which are characterized by uneven extensibility of various sites of a lung are the reasons of similar pheumothoraxes: meconium aspiration syndrome, hypoplasia of lungs, bullous malformation of lungs. Pheumothorax can become a complication of respiratory therapy or result from a lung injury (catheterization of subclavial and jugular veins by Seldingera method, sanitation of a tracheobronchial tree).
Clinical picture of a tension pneumothorax: a tachypnea, cyanosis, retraction of compliant places of a thorax, desynchronization with the ventilator, arterial hypotension, disturbance of a warm rhythm, the expressed asymmetry of a thorax (protrusion on the party of defeat), weakening of breath, a bandbox percussion sound, percussion and auskultativny signs of shift of a mediastinum in the healthy party, abdominal distention. The diagnosis is based on clinical data, radiological inspection, result of a diagnostic pleurocentesis, data of transillumination. The last method demands strict conditions of performance: rather darkened room or an opportunity to create local blackout and a bright source of cold light of small diameter (a strong small lamp, a venovizor, a svetoprovodnik from the endoscope). The light source is put to a thorax of the child: if in a pleural cavity there is no air, then light will form a small ring around a light source; in case of an extra pulmonary congestion of air there will be a wide circulation of light on a thorax. In case of development of an obvious clinical picture of a tension pneumothorax, it is not necessary to waste time for carrying out additional inspection, and to urgently carry out a lung decompression. The procedure is performed in sterile conditions. Position of the child on spin. When using side access it is necessary to fix a hand on the party of defeat behind the head. Place of a puncture: The IV-V mezhreberye on the peredneaksillyarny line, on the upper edge of an underlying edge. An anatomic reference point is the nipple which is located at the level of IV mezhreberye. For a puncture use a needle (18G), a catheter — "butterfly" (18G) or a vascular catheter on a needle (20–18G). For drainage by means of a thoracocentesis drainage tubes of 8-10 Fr or thoracic cannulas of 10-12 Fr are used. The needle or a catheter are connected to the syringe by means of the adapter with a clip (the 3-running crane). To Eagle (catheter) slowly moves ahead at an angle 45 ° in the cranial direction, tightening the syringe piston on itself. At free intake of air in the syringe air is removed from a pleural cavity. In case of a puncture a vascular catheter, the catheter moves ahead on a needle on necessary depth, the needle is removed, and the cannula connects to a tube of a system of aspiration. The catheter is fixed to skin. Depth of introduction of a drainage tube or catheter of 2-4 cm depending on body weight. The drainage is fixed by means of an adhesive plaster, when carrying out a thoracocentesis — the tube is fixed by 1-2 seams. Control the provision of a drainage radiological, in the presence of a minimal air change the provision of a drainage or put the second. Radiological control of a condition of lungs and the provision of a drainage after stabilization of the patient carry out at least once a day. If lungs finished and the drainage does not function during 12 h, then it should be pressed. If in 12 h on the roentgenogram the lung is straightened and there is no air in a pleural cavity, the drainage is deleted. Manipulation is carried out under local or general anesthesia.
In case of emergency, at right-hand pheumothorax, for a puncture it is possible to use the II-III mezhreberye on the sredneklyuchichny line.
Due to the high frequency of development of pheumothorax in newborn children, in offices where it is helped such patients, it is necessary always "to hold near at hand" set for a puncture and drainage of pleural space. For the purpose of prevention of pheumothorax implementation of protocols of maintaining children with respiratory problems is necessary, to be especially careful during manual ventilation (technology of ventilation, the indication of the manometer, existence of the PDKV valve), to use graphic monitoring when carrying out invasive IVL.
More SUV "terrible" form is the pneumopericardium — an air congestion in a cavity of a warm bag. Lethality at this SUV form reaches 90%. It is clinically shown by a cardiac tamponade: generalized cyanosis, dullness of warm tones, weakening of pulse, falling of arterial blood pressure. On the roentgenogram pnevmoyediastinum and a pneumopericardium look as an air aura with smooth edges (a dark rim) around a heart shadow. The air strip along the lower surface of heart over a diaphragm allows to differentiate a pneumopericardium from a pneumomediastinum. The main method of treatment — puncture removal of air from a pericardium. In order to avoid complications, this manipulation should be carried out under ultrasonography control.
The pneumomediastinum is most often combined with other SUV forms and characterized by accumulation of air in a mediastinum, has various options of a clinical current. At newborns the combination of pristenochny spontaneous pheumothorax and a pneumomediastinum is often noted. Clinically the priglushennost of cardiac sounds, a percussion bandbox sound over a breast is defined. Symptomatic treatment.
Pneumoperitoneum
The pneumoperitoneum usually is result of perforation of hollow body against the background of a current of a necrotizing coloenteritis, but maybe SUV option. In this case the pneumoperitoneum develops at the ventilated newborns who already have pheumothorax and a pneumomediastinum. Treatment of pheumothorax leads to spontaneous permission of a pneumoperitoneum.
Hypodermic emphysema
Hypodermic emphysema – an air congestion in hypodermic cellulose, occurs in newborns seldom and, generally at disturbance of the technology of drainage of pleural cavities. The symptom of "crunch" at a skin palpation is characteristic. This type of SUV does not demand treatment.