ACUTE RESPIRAORY INSUFFICIENY (ARI)

ACUTE RESPIRAORY INSUFFICIENY(ARI) Ivano-Frankivsk Medical university Department of anesthesiology and intensive therapy

ACUTE RESPIRATORY INSUFFICIENCY –acute respiratory insufficiency (ARI) is a body condition when the respiratory system fails to provide a normal gas content of the blood.

Etiological and pathogenic factors of ARI • acute respiratory obstruction of the respiratory tract; • restriction of the respiratory surface of the lungs by pneumothorax, exudative pleuritis, tumor; • diffuse disorder of gases through the alveolar-capillary membrane due to the development of pulmonary oedema; • chest injury; • functional disorders of the respiratory centre in case of exogenic and endogen intoxications, cerebral traumas, circulatory disorders in the stem of the brain; • neuro-muscular disorders of impulse transportation (tetanus, polyneuritis, myasthenia, poisoning with phosphoric organic compounds) • thromboemboly of branches of the pulmonary artery.

MANE STEPS • making diagnosis timely • giving emergency aid • performing intensive therapy

Pathogenesis • Disorders of permeability of the respiratory tract; • Disorders of respiratory biomechanics; • Disorders of gas diffusion; • Disorders of the pulmonary circulation; • Correlation changes of ventilation and perfusion.

Pathogenetic forms • bronchopulmonary; • thoracoabdominal; • central genic; • nervous-muscular; • cardiac-vascular; • mixed;

Diagnostic criteria • Clinical signs; • Results of laboratory examinations; • X-ray signs; • Other examinations;

The main syndromes of ARI • Hypercapnia; • Hypoxemia; • Hypoxia.

HYPOXIA Hypoxia stages concerning changes of the CNS Hypoxia stages concerning changes of respiration and cardio-vascular activity Euphoria Analeptic Apathy Toxic Hypoxic coma Terminal (agonic)

Postoperative respiratory insufficiency As reasons to consider • (1) the obstruction of overhead respiratory tracts above all things, bronchial obstruction, pneumothorax; • (2) then – pneumonia; • (3) then is pain, high intra-abdominal pressure

Postoperative respiratory insufficiency(emergency and etiotropic treatment) • 1. Hypoxia and hypercapnia improvement on general rules • 2. Improvement of airway obstruction (upper respiratory tract, bronchi) • 3. Improvement the restrictive disorders of breathing (pain, intra-abdominal and intrathoracic high-pressure) • 3. Improvement water-electrolyte disorders • 4. Therapy for infectious complications

Prophylaxis of complications 1.Adequate anesthesia 2. Early physical activity 3. Using of nasogastric probe only on strict indication 4. Depending on a concrete clinical situation to consider application (1) of the deep breathing exercises, (2) stimulating spirometery, (3) stimulation of cough, (3) postural drainage, (4) percussion and vibrating massage, (3) apparatus procedures (periods of breathing under positive pressure, permanent positive pressure in respiratory tracts)

Bronchial asthma • A patient is excited or stressed, dyspnea at rest, he can only sitting, talks separate words, respiratory rate is 30 per min, additional muscles take part in the breathing, there are loud wheezes during inspiration and expiration, pulse rate more than 120 per min, paradoxical pulse (during inspiration APsys > 25 mm Hg), FEV1 or PEF < 40% from a due or the best, PaO2 < 60 mm Hg, cyanosys is possible, PaCO2 > 42 mm Hg, SaO2 < 90%

Diagnostics of lifethreatening asthma • A patient is languid or in the entangled consciousness, respiratory rate is not a model, thoracoabdominal dissociation, rales are quiet or not heard, bradycardia, the absent of paradoxical pulse confirms the fatigue of respiratory muscles, FEV1 or PEF < 25% from a due or the best, deep hypoxemia and hypercapnia

Emergency of bronchial asthma severe exacerbation • Most comfortable position for breathing (fully to execute the patient wishes). • Inhalation of oxygen-air mixtures with FiO2 0,35-0,4. • 1A. If a patient can take a deep breath, inhalation b-2- adrenomimetic by the dosed inhaler (for example, Salbutamol). • 1B. If a patient can not take a deep breath – parenterally adrenalin for 0,3-0,5 ml 0,1% solution each 20 mines to 3 doses hypodermic (for the children - 0,01 mg/kg, maximum for 0,3-0,5 mg in the same mode) or terbutaline 0,25 mg each 20 mins to 3 doses hypodermic (for the children – for 0,01 mg/kg in the same mode), but it already indicate to the necessity of intubation and mechanical ventilation. • 1C. If the therapy by inhalation of b-2- adrenomimetic was uneffective in a previous 5-6 hours or there is the overdose (HR > / = 130 per min – pass to the step of 3B-3C (depending on the severity of state).

Lifethreatening asthma emergency Insert tracheal tube and start mechanical ventilation (oxygen-air mixture, low volumes, low frequency, large time of expiration) Drug therapy parenterally and by nebulizer in a breathing circuit as for the bronchial asthma severe exacerbation

Interstitial and alveolar pulmonary edema • Anxiety, weakness, general sweating • Dyspnea, the SpO2 is normal at the outset • Increase central venous pressure and/or pulmonary blood pressure • Interstitial: rough breath sounds and dry rales • Alveolar: fine moist rales, foamy rose sputum (it is too late) • On the frontal thorax X-ray film (there are roots of lungs enlargement, lung pattern enlarged and there are infiltrative shadows.

Pulmonary edema emergency for high AP and CVP 1.To give the patient comfort position in the bed to ease breathing 2.Oxygen therapy with FiO2 = 1,0, and then depending on success of SpO2 maintenance - oxygen therapy with FiO2 </= 0,5 and spontaneous breathing under permanent positive pressure or mechanical ventilation with the same FiO2 level. 3.Morphine 3-5 mg i.v. slowly, if necessary to repeat through 15 min (general dose 10 mg). 4.To determine and treat of causes 5.For eliminate of foaming (alcohol 33% 10-20 ml i.v. slowly, inhalation of dry oxygen, through an alcohol in place of water) 6. Hemodynamics correction: nitroglycerine 0,25-1,0 mcg/kg/min or Isosorbidedinitrate 1-10 mg/hour i.v. by the dropper, and/or furosemide to 1 mg/kg i.v.

Pulmonary edema emergency for low AP (independently from CVP) 1.Oxygen therapy with FiO2 = 1,0, and then depending on success of SpO2 maintenance – oxygen therapy with FiO2 </= 0,5, and spontaneous breathing under permanent positive pressure or mechanical ventilation with the same FiO2 level. 3.Morphine 3-5 mg i.v. slowly, if necessary to repeat through 15 min (general dose 10 mg). 4.To determine and treat of causes 5.For eliminate of foaming (alcohol 33% 10-20 ml i.v. slowly, inhalation of dry oxygen, through an alcohol in place of water) 6.Hemodynamics correction inotropic support: Dobutaminum 2-3 mcg/kg/min or dopamine 2-5 mcg/kg/min, their combination is possible

Diagnostics of drowning 1.(a) Breathing – from dyspnea and cough to acute respiratory insufficiency with a severe hypoxia and hypercapnia; bronchospasm is possible; (b) Neurologic – from excitation and agitation to the coma and convulsion; (c) Circulation – heart rate disturbance, elevated or lowered AP, may be cardiac arrest 2. “Wet drowning” - cyanosis, rose large-meshed foam at the mouth 3. «Dry drowning » - cyanosis, white close-meshed foam at the mouth 4.Syncopal drowning (reflex cardiac arrest) – skin pallor, foam at the mouth is absent. 5. Fresh water drowning - rapid absorption water from respiratory tracts with the gradual development of noncardiac pulmonary edema 6. Sea water drowning persistent foaming in alveoli and respiratory tracts, and alveolar pulmonary edema from the onset

Emergency for drowning • 1. Depends not on the type of drowning, but on the severity of state: • (а) Cardiac arrest – start CPR immediately • (б) unconsciousness, breathing disorder or absent, stable circulation and lateral position, oxygen therapy with maximal FiO2, intravenous access in the «opened line» mode or symptomatic correction of hemodynamics • (в) consciousness, breathing and circulation without the expressed disturbances - a prophylaxis of further careless conduct as a result of excitation, warming and oxygen therapy with FiO2 0,4-0,5. • 2. Hospitalization is obligatory in all of cases

Pulmonary embolism diagnostics • Acute massive occlusion - acute system hypotension with or without a fainting, severe refractory hypoxia • The pulmonary infarction (1) early signs: shortness of breath, tachycardia, coronal pain, periodic collapses; (2) late signs: fervescence, pleura pain; (3) late rare sign: haemoptysis. • Pulmonary embolism without infarction - dyspnea, tachypnea, tachycardia • Classic X-ray signs (Appendix 2) • Classic ECG-signs (Appendix 3) • Diagnosis verification - pulmonary arteries spiral CT scan or pulmonary angiography • Diagnosis rejection: if the D- dimers content less than 500 ng/l and there are not pulmonary embolism X-ray.

Air embolism can be produced during inspiration if negative intrathoracic pressure draws air into an open vein, an event most likely to happen during a neurosurgical or ear, nose, and throat procedure in which the patient sits upright and the operative wound is above the level of the heart. Air bubbles become trapped in pulmonary arteries and right ventricle where they mechanically impede blood flow. Reactions at the gas-fluid interface trigger blood clotting and the accumulation and activation of neutrophils. Small fibrin and platelet thrombi are found in pulmonary arteries. The physiologic consequences include transient airway constriction and vasoconstriction with great increases in pulmonary vascular resistance and pulmonary artery pressure. With large emboli pulmonary edema, hypoxemia, systemic hypotension and myocardial ischemia are seen. Fatalities have been reported with embolism of 100 ml of air.

Amniotic fluid emboli are a rare complication of pregnancy. Infusion of amniotic fluid occurs during tumultuous uterine contractions when the head is in the birth canal. The amniotic fluid is forced through a rupture in the chorion into the maternal veins, precipitating severe dyspnea, tachypnea, and hypotension. Disseminated intravascular coagulation is a common consequence. At autopsy the lungs are hemorrhagic. Squamous cells are lodged in the arterioles. Amniotic debris also contains lipid and mucin, which can be identified with appropriate stains. Reportedly, the clinical diagnosis can be confirmed by the demonstration of squamous cells in blood withdrawn by pulmonary artery catheter.

Fat embolism is the result of abrupt pressure changes in the long bones, which rupture thin walled venous sinuses and force marrow fat into them. It embolizes to the lung. In addition, levels of plasma triglycerides, free fatty acids, and lipase rise as part of the stress response. Endothelial damage is caused by fatty acids released from embolized fat and by mediators released during associated blood coagulation. Fat emboli can be recognized by ordinary histopathologic sections as sharply delimited, empty-appearing capillary loops or arterioles, but frozen sections stained for fat are required for confirmation. • Bone marrow emboli commonly follow vigorous cardiopulmonary resuscitation. Like thrombotic emboli they become adherent, endothelialized, and eventually organized.

Foreign-body embolism can result from introduction of foreign material into the veins during medical procedures but is also common among intravenous narcotic users. Particles of insoluble material added as “fillers” to drugs intended for oral use embolizes to the lung and impact in arterioles and small muscular arteries where they cause thrombosis and proliferation of intimal cells. Often they migrate into the perivascular space or interstitium where they give rise to foreign-body granulomas composed of macrophages, multinucleated giant cells, and a few lymphocytes. The process of migration appears to involve the production of granulomatous response in the vascular wall with disintegration of muscle and elastic tissue. In cases where lesions are not numerous, their detection is aided by the use of polarizing filters, since cornstarch and talc, two of the materials commonly used as fillers, are strongly birefringent. When the vascular thrombosis is widespread, pulmonary hypertension results. Lesions may resemble those of primary pulmonary hypertension, particularly in view of the cellular proliferation induced by the foreign material. Extensive interstitial granulomas can produce roentgenographic nodularity and a restrictive ventilatory defect. • Tumour embolism: Tumour emboli are occasionally seen in the lung and are thought to be the source of the lymphangitic form of carcinoma.

Classic ECG signs of pulmonary embolism The S1-Q3-T3 syndrome - a deep S wave in I lead and deep Q wave in the III standard lead, and the T wave in the III lead becomes negative (to 15% cases of PE) Suddenly onset of right heart overload - dextrogram, ECG-signs of right ventricle hypertrophy, right bundle-branch block Suddenly onset of supraventricular arrhythmia – atrial fibrillation, ciliary arrhythmia, paroxysmal tachycardia, extrasystole.

Classic X-ray signs of pulmonary embolism Classic X-ray signs of pulmonary embolism Fleishner lines - linear veins (areas of flat atelectasis), spreading parallell cupula of diaphragm The Westermarck’s symptom - the area of relatively hypoperfusioned pulmonary tissue The Hampton’s hill - the wedge with basis, turned to the pleura, occur by the pulmonary infarct (in 12-36 hours after embolism onset) Pal’s symptom - an increase of right descending artery

Pulmonary embolism emergency • CPR – if indicated • Oxygen (since FiO2 1,0), spontaneous breathings or mechanical ventilation, standard indications • Narcotic analgetic (Morphine 5-10 mg i.v. or Promedol 20 mg subcutaneous) • Hemodynamics management • Unfractionated heparin bolus 80 U/kg i.v.

Hemodynamics management for pulmonary embolism • an ephedrine is 5-10 mg or epinephrine of 0,05-0,5 mcg/kg/min (intravenously by dropper, also diminish bronchospasm, but can increase pulmonary arterial pressure and tachycardia) or selective bronchodilatation (short action b-agonists: salbutamol by the dosed inhaler or nebulizer, doses and tactic see “Status asthmaticus”) + • selective hemodynamics support (Dobutamine 5-10 mg/kg/min); the second line preparations - Dopamine 5-15 mcg/kg/min or Norepinepfrine 0,2-1,0 mcg/kg/min intravenously by dropper + • pulmonary circulation unload (Nitroglycerine from 10-20 mcg/min or Isosorbide dinitrate from a 1 mg/h to 10 mg/h intravenously by the dropper with a carefulness – the system AP reduces) as decreased central venous pressure – to increase the infusion therapy volume on polyionic solutions (under CVP and ECG-signs of right heart load control)

Diagnostics of aspiration • Cough, stridor • Breathing disorders, apnea or tachypnea, wheezes • Hyperthermia • Visible in a pharynx castric content (or blood or pus) • Bronchospasm • Abundant tracheary secretion

Aspiration emergency • To make patient in Trendelenburg's position, if it possible – with right side elevated • To aspirate the content of mouth, throat, and respiratory tracts • Oxygen inhalation with FiO2 1,0 + mechanical ventilation (on general indications) • Symptomatic correction of hemodynamics disturbances • Periodically to repeat a suction from trachea and bronchi • – agonists for persistent bronchospasm • Antibiotics only for the intestinal content aspiration • Bronchoscopy only for the hard fragments aspiration

Diagnostics of airway foreign body obstruction • Sudden worsening • Games, shallow objects meal, bad mastication • Cough, pant. • Mild aspiration - clear consciousness, vertical position, ringing voice, loud cough, inhalations between the fits of coughing • Moderate aspiration - clear consciousness, vertical position, unsounding voice, soundless cough, inhalation between the fits of coughing is not succeeded • Severe aspiration - the mental confusion, can not save vertical position, a cough and breathing go out or went out.

Emergency for airway foreign body obstruction Mild aspiration – to encourage a cough, sedative conversation, supervision to complete eliminated of obstruction. Moderate aspiration – postural massage. If progression to the severe obstruction – to change tactic as described below. Severe aspiration - (1) simple manoeuvres of airway support (2) to examine the mouth cavity and delete all visible foreign objects and liquids (3) to give 2 rescue breath, (4) to give 30 chest compressions as during CPR (5) repeat if necessary from a step (1). Chest compressions execute, even if a carotids pulse is yet determined! Tactic is changing as changing the obstruction severity.

Intensive care aspiration syndrome algorithm • Breath correction on general rules. Prophylaxis and treatment of noncardiogenic pulmonary edema, aspiration pneumonia, atelectasis • Circulation correction on general rules. Prophylaxis and treatment of arrhythmias and cardiac insufficiency • Protective (drug and nondrug) cerebral functions braking, prophylaxis and treatment of post-hypoxic cerebral edema

Respiratory distress syndromeof adults Acute onset PaO2/FiO2 < 200 mm Hg independently of the level of end expiratory positive pressure Bilateral infiltration on the frontal chest X-ray film Pulmonary capillary wedge pressure < 18 mm Hg. or absence the signs of left atrium hypertension

Emergency for acute respiratory distress syndrome • Resuscitation on indications • Gases exchange correction to goal level (рН no less than 7,25, PaO2 50-70 mm Hg, PaCO2 not below 35 mm Hg). Sequence of therapy aggressiveness increase: spontaneous breathing under permanent positive pressure with FiO2 < 0,4  mechanical ventilation with end expiratory positive pressure 4-5 mm Hg with same FiO2 level  step-by-step alternating increase of end expiratory positive pressure and FiO2. • Continuation glucocorticoid therapy (Dexamethasone i.v. 1mg/kg every 12 or a 24 hours) • Exogenous surfactant as soon as possible

Intensive care adults respiratory distress syndrome algorithm • Treatment of underlying diseases • Gases exchange correction of (spontaneous breathing under permanent positive pressure with FiO2 < 0,4  mechanical ventilation with end expiratory positive pressure 4-5 mm Hg with same FiO2 level  step-by-step alternating increase of end expiratory positive pressure and FiO2.) • Minimization of oxygen necessities (pain control, treat convulsions, hyperthermia, hypothermia with shivering) • Minimization of CO2 products (the same in general + diet with the diminished amount of carbonhydratess and increased amount of fats) • After shock completion - minimization of intravenous infusion, oral (probe) liquid supplying • Postural pose chance every 2 hours, during ventilators support prone position twice per day for 4-6 hours duration.

Obstruction of the respiratory passages (stuck tongue) I. Safar’s method. The patient’s position is horizontal on the back. The 1st step. Press your hand on the patient’s forehead and bend his head at the atlantooccipital joint, at the same time raise his chin by the two fingers of another hand. The 2nd step. Fix the lower jaw with your fingers and raise it forward and upward: the lower teeth should be at the level with the upper ones. If AVL must be conducted – the 3rd step: open the patient’s mouth.

II. Introduction of the air tube through the mouth. The patient’s position is on the back or on one side. 1st variant. Open the mouth. Press the spatula on the base of the tongue, move it forward from the oral pharynx. Introduce air tube by its curved side to the chin that its distal end does not touch the posterior wall of the oral pharynx; the flange of the air tube should come 1-2 cm forward from the incisors. Move the lower jaw forward and upward, it will allow the tongue to remove from the oral-pharyngeal wall. Press the air tube and insert it 2 cm into the mouth that its curve lies on the base of the tongue. 2nd variant. The air tube can be introduced into the mouth by its curved side to the hard palate (without spatula). When its end touches the uvula of the soft palate, the air tube is turned to 180° and moved to the base of the tongue.

Prolonged obstruction of the respiratory tract, apnea Tracheal intubation (oral-tracheal). While conducting intubation the preparation for anaesthesia are used (thiopental sodium 1% 4-5mg/kg of the body weight, ketamine 5% 2mg/kg, ethomidat 0,3 mg/kg, diazepam 0,15-0,3 mg/kg, mydazolam 0,1-0,4 mg/kg) and myorelaxantes (ditilin 2% 1-1,5 mg/kg). For the patients in coma condition direct laryngoscopia and intubation can be conducted without anaesthesia. Hold laryngoscope in the left hand closer to the connection with the blade. The patient’s mouth should be opened widely by means of the thumb and pointer of the right hand applied on the upper and lower molars. The blade of laryngoscope is carefully inserted into the oral cavity between the upper palate and tongue to the epiglottis, the tongue is moved upward and to the left. While moving the blade one should orientate to the uvula of the soft palate and epiglottis.

Prolonged obstruction of the respiratory tract, apnea • Depending on the kind of the blade its end is placed either under the epiglottis (Miller’s kind) or between the epiglottis and base of the tongue (Makintosh kind). Fix the wrists and raise the hand of the laryngoscope upward and forward to open the glottis. Excessory movements of the left wrist backward should be avoided to prevent strong pressure on the upper teeth. Intubation tube is inserted along the blade through the glottis to the point when the cuff of the tube is lower the vocal cords. A club-like curved conductor is inserted into the intubation tube, its end should not advance from the borders of the tube. Correct position of the intubation tube is determined by the excursion of the chest and auscultation of the lungs during AVL. Respiratory sound should not be hear in the area of the stomach. The cuff is blown with 5-10 ml of air and the intubation tube is fixed.

Obstruction due to oedema, bleeding, foreign body Cricotomia (conicotomia). The position of the patient is horizontal on the back, the neck is in a neutral position. Treat with antiseptic and apply sterile cloth on the anterior surface of the neck (if there is some time); palpate the cricoid’s ligament lower the thyroid cartilage on the middle line; fix firmly the thyroid cartilage with the fingers of the left hand and make a transversal cut 2 cm long through the cricoids ligament; insert tracheal dilator to the side of the lower part of the trachea and carefully open the edges of the wound. If there is no tracheal dilator the hand of scalpel can be inserted into the trachea transversally and turned to 90° to widen the opening in the cricoids ligament; insert tracheostomic tube into the trachea (or endotracheal tube), blow the cuff and perform AVL by the sac with 100% oxygen.

Obstruction of the respiratory tract with sputum Tracheal catheterization through the skin (Seldinger’s method). The position of the patient is horizontal on the back, the neck is in a neutral position. Under local anesthesia puncture the trachea between the first and second rings of the trachea. The needle is directed from upward to downward obliquely. A fiber is inserted through the needle into the trachea, the needle is removed, catheter is inserted through the fiber 4-5 cm deep to the side of bifurcation. The catheter is used for high frequency AVL, tracheal instillation of moistering means and detergents, aspiration of sputum.

Obstruction with a foreign body on the level of the pharynx and upper portion of the trachea.Apnea, AVL Heimlich method. The position of the patient is horizontal on the back or vertical. Two methods are used: strong push in the epigastric region directed upward to the diaphragm; press the lower portions of the chest. In some cases a number of blows between the scapulae are made.

Laryngeal mask. The position of the patient is horizontal on the back. The head is moderately raised with simultaneous unbending at the atlantooccipital joint (improved position). The patient’s mouth should be opened widely by means of the thumb and pointer of the right hand applied on the upper and lower molars. With the thumb and pointer of the left hand fix the air tube, and with the middle finger press the cuff to the hard palate, insert the mask into the oral cavity and laryngeal portion of the throat. The cuff is blown by means of the syringe with 10-15 ml of air (depending on the size of the mask), thus the throat and edges of the mask are hermetically sealed.

Apnea Artificial ventilation of the lungs “from mouth-to-mouth” and” from mouth-to-nose”. The patient’s position is horizontal on the back. Permeability of the respiratory tract is renewed by triple Safar’s method. The mouth and nose of the patient are covered with cloth, the mouth is closely seized by the lips of reanimator, the nostrils of the patient are held with the fingers. Air is blown into the mouth of the patient (into the mouth and nose in little children) after previous inspiration. The time of blowing up to 1,5-2 sec., volume up to 1 litre. Expiration is passive. During expiration the head of the patient is turned to the opposite side. Efficacy of respiration is controlled by the expansion of the chest. Frequency of respiration should be 14-16 per minute.

Artificial ventilation with the sac through the oral-nasal mask. The mask of a proper size is taken in the left hand, the thumb and pointer press around the obturator (ring). Put the mask on the face that a narrow part is placed on the edge of the nose and a wide one on the alveolar process of the lower jaw. The mask is hermetically sealed on the face. Press the mask with the thumb and pointer, fix and push the lower jaw with the middle and fourth fingers. At the same time the head is unbended at the atlantooccipital joint. The small finger of the left hand is placed at the angle to the lower jaw and pushes it forward. Conduct respiratory movements in turn pressing and releaving the sac with the right hand. In severe cases both hands are used to fix the lower jaw, respiration is conducted by an assistant.

ACUTE RESPIRAORY INSUFFICIENY (ARI)