Presentation on theme: "Upper airway obstruction in pediatric"— Presentation transcript:
1Upper airway obstruction in pediatric patients from anesthesiologist vewProf. Mirjana ShosholchevaUniversity clinic of surgery “St. Naum Ohridski”Medical faculty-Skopje, MacedoniaOne of the most challenging clinical situations mandating nursing skills is assessment, rapid diagnosis and management of the acute airway obstruction in children. Although many airway disorders exist, obstruction of the upper airway is the most potentially life-threatening situation.The main goal is to prevent cardiac arrest or irreversible brain damage that occurs within minutes of complete airway obstruction.Good outcome can be ensured by appropriate management with implementation of preventive aspects of airway obstruction and training in basic life support techniques, as this situation requires an immediate, aggressive response.
2DisclosuresNo financial disclosuresNo conflict of interest
3Key points Causes of airway obstruction in children Signs of airway obstructionAirway obstruction with foreign bodyAirway obstruction during emergence from anaesthesiaManagement of laryngospasmSecuring the airway in a child with airway obstruction
4Epidemiology and mortality Upper airway obstruction accounts for up to 15% pediatric emergency*The major causes are:Viral croup (80%)**Epiglotitis (5%)Foreign body aspirationFailure to manage the airway is the leading cause of preventable pediatric deathsInfants and children decompensate more quickly compared to adultsNarrowing of the upper respiratory tract has an exponential effect on airflow because linear airflow is a function of the fourth power of the radius (Hagen-Poisell equitation). Although UAO occurs at any level of the upper respiratory tract, laryngeal obstruction has a particular importance because larynx is the narrowest portion of the upper airway. The narrowest portion of the larynx is at the glottis in adults and the subglottis in infants* Loftis L. Emergent evaluation of acute upper airway obstruction in children.Reprint from Up to date** Manno M. Pediatric respiratory emergencies: Upper airway obstruction and infections. In: Marx J, ed.Rosen's Emergency Medicine: Concepts and Clinical Practice . 7th ed. Philadelphia, Pa: Mosby Elsevier;2009:chap 166
5Important causes of airway obstruction in children Life-threatening emergencyLaryngospasm after trachealextubation –major of UAO after surgeryDepressedconscious levelCongenitalanomaliesPost-extubation laryngospasmAnaphylactoidreactionsRapidlyprogressiveAirwayobstructionInfectionsMany of the infectious causes of upper airway obstruction have lost their threat today as a result of the progress made in preventing and treating these infections.Infections: Viral tracheobronchitis (croup); infectious mononucleosis| Bacterial: epiglottitis, tracheitis, tonsillitis, retropharyngeal, peritonsilar abscessForeign bodies: airway foreign body, esophageal foreign bodyTrauma: blunt and penetrating injuryCongenital anomalies: choanal atresia, micrognathia, macroglossia, hereditary angioedemaAcute upper airway obstruction from any cause can be a life-threatening emergency in the pediatric patient and unless promptly diagnosed and appropriately managed, complete obstruction will result in respiratory failure followed by cardiac arrest in a matter of minutes.Thermal injuryAirwayforeign bodyTrauma*Morton NS. Large airway obstruction in children: causes, assessmentand management. Update Anaesthesia 2004; 18 (article 13):1
6Signs of airway obstruction in children conscious patientunconscious orsedated patientmarked respiratory distressaltered voicedysphagiathe hand-to-the-throat choking signstridor, facial swellingprominence of neck veinsabsence of air entry into the chesttachycardiainability to ventilate witha bag-valve maskasphyxia progresses to cyanosisbradycardiahypotensionirreversible cardiovascular collapseA quick evaluation considering age group, history, physical examination, and clinical circumstances helps determine the site and cause of obstruction, the severity of the obstruction, and the need to establish an airway urgentlyStridor is heard during the entire respiratory cycle but typically intensifies during inspiration and is usually more prominent above the neck. The presence of stridor indicates severe airway obstruction, (airway passage <5 mm) but unfortunately does not help to specify its nature or location.Obstructive noise or stridor is specific for UAO
7Specifics regarding signs of airway obstruction in children Mild upper airway obstructionchild recovering from anaesthesiatonsillar hypertrophy and obstructive sleep apneaSigns of partial upper airway obstruction include biphasic snoring and mild desaturationSevere, non-complete, progressive airway obstructionincreased work of breathingrespiratory failureHypoxemiacardiac arrestChildren with severe croup, tracheitis, epiglottitis, airway burnsTrauma, depending on its severity and location, may produce immediate or progressive obstruction
8Signs of increased work of breathing TachypneaParadoxical respiration “See-saw” pattern of breathing(dyssynchrony between rib cage and abdomen)Suprasternal, intercostal, and subcostal retraction along with an increased use of accessory muscles of respirationauto CPAPPosition: Infants may assume an opisthotonic position; the "tripod" or sniffing position is seen in the older child
9Stridor Inspiratory stridor Expiratory stridor airway compromise atthe supraglotic or laryngeal levelStridor: inspiratory stridor indicates airway compromise at the supraglotic or laryngeal level, while expiratory stridor is indicative of intrathoracic obstruction. It is very important to be noticed that the magnitude or severity of stridor does not correlate with the severity of obstructionintrathoracic obstructionThe magnitude or severity of stridor does not correlate with the severity of obstruction
10Signs of ineffective breathing and respiratory failure: CyanosisAltered consciousnessBradypnea, apneic spelssSilent chest in spite of vigorous effortPost-extubation laryngospasm,angiooedema andanaphylactoid reactionsCompleet airway obstructionCompleet airway obstruction is signaled by gagging, choking. absent breath sounds and aphonia in the case of large foreign bodu aspiration. this rapidly progresses to cyanosis, bardycardia and cardiac arrest.Complete airway obstruction in the abscense of foreign body aspiration is seen in post-extubation laryngospasm, angiooedema and anaphylactoid reactionsChoking, absent breath sounds and aphoniaThis rapidly progresses to cyanosis, bardycardia and cardiac arrest
11Airway obstruction with foreign body Foreign-body aspiration is a relatively frequent accident anda leading cause of accidental death in children under 5 years of ageDiagnosis of foreign body aspiration should be suspected in children who do not respond to appropriate interventionLaryngeal impaction is life-threatening(large or sharperdged foreign bodies may lodge in the larynx)Most foreign bodies pass the vocalcords and lodge in the lower airways (bronchi -80%)Symptoms can mimic other diseases such as croup or asthma
12Airway obstruction with foreign body Nasal foreign bodiesunilateral rhinorrhea and stinking breathOropharyngeal foreign bodies :mouth breathingChildren with a history of choking and subsequent symptoms must be referred to immediate bronchoscopy!A diagnosis of foreign-body aspiration should also be considered whenever a child exhibits unexplained symptoms that are refractory to medical treatment and are consistent with airway obstructionWhat about the child who has stridor and wheezing?The causes of stridor and wheezing in older infants and children includeforeign bodies in the airway and in the esophagusand combination of infectious causes
13Management of airway obstruction with foreign body *if the child can cough and verbalized it is placed inthe position of comfort and oxygen is givenIV line placement and other interventions which may agitatethe child in this case are avoidedX-ray evaluation for localization can be performedurgently in stable childrenThe presence of asphyxia indicates the needfor immediate resuscitation and securing the airway*Schmidt H., Manegold BC. Foreign body aspiration in children. Surg Endosc 2000; 14:644-8
141. Mild oedema of the respiratory mucosa “Circulus viciosus”BLS maneuvers(Heimlich, Guidel )Most patients canbe dischargedwithin 24 hdirect laryngoscopyMagill forcepsor suctionComplications1. Mild oedema of the respiratory mucosa2. Tracheobronchitis3. granulation tissueflexiblebronchoscopyWhen BLS maneuvers are not successful, direct laryngoscopy should be performed. In some cases the foreign body may be removed with a Magill forceps or suction when it is above the vocal cords. Extraction with rigid bronchoscopy is usually performed in the most cases for suspected or confirmed obstruction with foreign body. Prior evaluation by flexible bronchoscopy might be justified in unclear cases but provisions should be made to provide immediate rigid bronchoscopic management. Complications after successful foreign-body removal are rare. Inflammatory responses, such as mild oedema of the respiratory mucosa, tracheobronchitis or granulation tissue resolve without sequelae. Routine use of steroids or antibiotics is not indicated. Most patients can be discharged within 24 h. Repeat bronchoscopy may be indicated if there is uncertainty about complete removal. A short course of corticosteroids may be helpful before repeat bronchoscopy in cases where mucosal swelling does not allow complete visualisation of the lower airways. Potential complications, such as bronchial stenosis, bronchiectasis, abscess formation or perforation are more likely to occur the longer the foreign body remains in the airways.short course of corticosteroidsRepeatbronchoscopyrigid bronchoscopy
15The foreign body is withdrawn by a forceps through the bronchoscope Child is in respiratory distress!inhalational induction with 100% oxygen and sevofluraneAfter loosing the consciousness. i.v. cannulaTIVA with propofol and fentanylgentle assistance with inhalational techniquecords are sprayed with local anaestheticrigid bronchoscope with a ventilating side arm is inserted,facilitated by laryngoscopyWhen the child is in respiratory distress, inhalational induction with 100% oxygen and sevoflurane is given. After loosing the consciousness. i.v. cannula is introduced. TIVA using propofol and fentanyl is administrated: the child may become apneic after induction if the work of breathing was severely increased. Children may require gentle assistance even with inhalational technique. The cord are sprayed with local anaesthetic and a rigid bronchoscope with a ventilating side arm is inserted, facilitated by laryngoscopy. Desaturation may occur as “the clean” lung is excluded from ventilation and higher FiO2 may be required. High ventilating pressures are not recommended, as the foreign body, if partially mobile, might be displaced into a distal airway and than retrieval might be more difficult. Dexamethadone is administrated to reduce edema and stridor. The foreign body is withdrawn by a forceps through the bronchoscope. Laryngeal edema might be worsen after multiple insertions of the rigid bronchoscope, and post-procedure reintubation might be required.higher FiO2The foreign body is withdrawn by a forceps through the bronchoscopeDexamethadoneLaryngeal edema might be worsening after multiple insertions of the rigid bronchoscope, and post-procedure reintubation might be required
16Securing the airway in a child with airway obstruction – General considerations Laryngoscopy and intubationvolatile anaestheticsSevoflurane might be choice, but its use has some controversy,because lower potency of sevoflurane may not permit intubationThe Jackson-Rees modification of Ayer,s “T piece” circuit- CPAPFor the intubation, volatile anaesthetics are used. Sevoflurane might be choice, but its use has some controversy, because lower potency of sevoflurane may not permit intubation.In many centers halothan in 100 oxygen is still very frequent choice. The concentration is increased by 0.5% every 10 breaths, gradually increasing the concentration up to 5%.Attempts to assist ventilation against complete obstructionare usually futile!Alveolar ventilation in these children is severely compromised. Uptake of volatileagents is very slow and induction of anaesthesia may take more than 15 min
17Any attempt at “asynchronous” assistance leads to complete obstruction, especially in large foreign bodies“Synchronized” assistance (analogous to triggered ventilation)is very helpful to maintain oxygenation
18intubation is difficult or impossible As the depth of anaesthesia increases, the child may be gradually lowered to the supine positionflexible fiberopticbronchoscopyintubation is difficult or impossibleIf the condition of the child deteriorates, cricothyrotomy and ventilation through a T piece circuit can be consideredJet ventilation is not appropriate as it may lead to barotrauma
19The safest option is emergent tracheostomy under musk anaesthesia for most children who cannot be intubated in one or two attempts
20Controversy associated with heliox therapy in UAO Heliox has been used in several conditions: postextubation laryngeal edema, tracheal stenosis or extrinsic compression, status asthmaticus and angioedemaTo be effective, the helium–oxygen ratio must be at least 70:30Although the work of breathing and dyspnea improves to some degree with the use of heliox, the mechanical obstruction is still in placeThe use of heliox in patients with severe UAO should only be used to provide temporary support pending definitive diagnosis and management
21Algorithm for management of upper airway obstruction
22Infective causes of airway obstruction acute clinical syndrome of hoarse voice, barking cough and stridorToday many of the Infective causes of airway obstruction have lost their threat as a result of the progress made in preventing and treating these infections. Prompt recognition and appropriate management of the child presenting with upper airway obstruction due to the infective causes remains critical, because certain causes can progress rapidly from a mild to a potentially lifethreatening disease stateRadiological presentation of subglottic oedema in viral croup (left) compared with a normal trachea (right)Endoscopic view of subglottic oedemain viral croupThere is some controversy regarding treatment with epinephrineUsually affects children from 6 months to 4 years of age, with a peak incidence at 2 years of age
23Epiglotitis Controversy! To look or not to look Epiglottitis is a serious, life-threatening infection and an airway emergency. It is characterised by acute inflammatory oedema and hyperaemia involving the supraglottic structures, above the epiglottis itself and the aryepiglottic folds.Supraglottitis is a more appropriate descriptionAlso, controversy exists regarding management of the epiglottitis although the incidence of this disease has decreased dramatically. To look or not to look, visualization of the epiglottitis in a child with acute stridor and in whom the diagnosis of epiglottitis is not usually advocated. However the presence of anesthesiologist provides reliable approach in this case.Schematic (left) and endoscopic view (right) of epiglottitis.Lateral neck radiographs of a normal child (left)and a child with epiglottitis with the typical thumb sign (right).Conversely, epinephrine is not effective in the treatment of epiglottitisand may be deleterious.Controversy! To look or not to look
24Airway burnsHeat produces an immediate injury to the airway mucosa edemaSuspect for inhalation injuryExposure in an enclosed spaceDecreased level of consciousness, confusionSoot in mouth, naresCarbonaceous sputumAirway burns often progress rapidly to acute upper airway obstruction, but still allow time for the child to be intubated under anaesthesia.Swelling, ulceration of oral mucosa or tongueDyspnoeaIncreased work of breathingHoarsenessOxygen saturations <94% in airCaboxyhaemoglobin >5% on co-oximetryStridor, wheeze, crepitations
25Effect of deep face burns on airway maintenance are: Airway obstruction by intraoral and laryngeal edemaAnatomic distortion by face and neck edema, which increasesthe difficulty of endotracheal intubationOral edema decreasing clearance of intraoral secretionImpaired protection of the airway from aspirationMaintaining an adequate airway!There is insufficient data to support a treatment standard or a treatment guideline for the diagnosis of inhalation injury.However, maintaining an adequate airway is essential for successful early management. There are four standard criteria (the four P’s) for the need for endotracheal intubationA judgment decision must be made in the initial assessment as to whether the airway can be managed safely without an endotracheal tube. When in doubt, it is safer to intubate, as airway burns often progress rapidly to acute upper airway obstruction, but still allow time for the child to be intubated under anaesthesiaMaintain airway patencyProtect against aspirationPulmonary toilet to decrease mucous plugging and infection risksNeed for positive-pressureWhen in doubt, it is safer to intubate!
26Endotracheal tube complications TRAUMATIC LESIONSDamage from endotracheal intubation andtracheotomyEven the dictum that ‘cuffed endotracheal tubes should not be used inchildren under the age of 8 years’ can no longer be maintainedsince the development of high-volume, low-pressure cuffs*Endotracheal tube complicationsincorrect size, traumatic or multiple intubationsup and down movements of the endotracheal tubeinadequate analgesia and sedation, whereby the infants struggle while intubatedComplications and damage of the upper airway may occur during the endotracheal intubation as so as when longterm endotracheal intubation was introduced for pediatrics requiring prolonged ventilator support. Acquired subglottic stenosis is problem that can be resolved with experience of choosing appropriately sized tubes thus preventing tube trauma and particular care of the intubated patient*Newth CJL, Rachman B, Patel N, Hammer J. The use of cuffed versusuncuffed endotracheal tubes in pediatric intensive care. J Pediatr 2004; in press
27Cuff vs Uncuffed Endotracheal Tube Controversial issueTraditionally, uncuffed ETT recommended in children < 8 yrs old to avoid post-extubation stridor and subglottic stenosisArguments against cuffed ETT: smaller size increases airway resistance, increase work of breathing, poorly designed for pediatric patients, need to keep cuff pressure < 25 cm H2OArguments against uncuffed ETT: more tube changes for long-term intubation, leak of anesthetic agent into environment, require more fresh gas flow > 2L/min, higher risk for aspiration-
28Concluding Recommendations -For “short” cases when ETT size >4.0, choice of cuff vs uncuffed probably does not matterCuffed ETT preferable in cases of:high risk of aspiration (ie. Bowel obstruction),low lung compliance (ie. ARDS, pneumoperitoneum, CO2 insufflation of the thorax, CABG),precise control of ventilation and pCO2 (ie. increased intracranial pressure, single ventricle physiology)Golden, S. “Cuffed vs. Uncuffed Endotracheal tubes in children: A review” Society for Pediatric Anesthesia. Winter 2005 edition.
29Laryngeal Mask Airway – WHEN? Supraglottic airway deviceFlexible bronchoscopy, radiotherapy, radiologic procedures, urologic, orthopedic, ENT and ophthalmologic cases are most common pediatric indications for LMAUseful in difficult airway situations, and as a conduit of drug administration (ie. Surfactant)Different types of LMAs: Classic LMA, Flexible LMA, ProSeal LMA, Intubating LMADisadvantages: Laryngospasm, aspiration
30Concern:light plane of anesthesia! Airway obstruction during emergence from anaesthesiaPostoperative laryngospasm - life-threatening complicationaspiration, airway obstructionTracheal extubationawakedeep anesthesiaConcern:light plane of anesthesia!Tracheal extubation can be performed while pediatric patients are awake or under deep anesthesia. Both techniques have their pros and cons.A small number of studies involving children show a greater incidence of upper airway complications with awake extubation as a result of increased airway reactivity. However, the endpoint for wakefulness in these studies was taken as swallowing; the incidence of respiratory complications dramatically decreased when extubation was performed when eyes were open, with spontaneous ventilation. Extubation under deep anaesthesia decreases cardiovascular stimulation and reduces the incidence of coughing and straining on the tube.Laryngospasm is most frequently caused by local irritation by blood or saliva and is likely to occur during light planes of anaesthesia, when the children are neither able to prevent this reflex nor generate an adequate cough. The incidence can be reduced if they are left undisturbed in the lateral recovery position until they wake up.local irritation by blood or salivalight planes of anaesthesiaChild undisturbed - in the lateral recovery positionHypoventilationHypoxemiaHypercarbiaCardiac dysrhythmiasCardiac arrest
31Emergence and extubation: A systemic approach Can this patient be extubated while deeply anesthetized?YesNoNo rezidual NMBEasy musk ventilationEasily intubatedNot at increased risk forregurgitation/aspiration- NormothermicDifficult musk ventilationDifficult intubationResidual NMB presentFull stomachCan this patient be extubated immediately followingsurgery and emergence from general anesthesia?
32Can this patient be extubated immediately following surgery and emergence from general anesthesia?YesNoAwakeFollowing commandsBreathing spontaneuoslyWheel oxigenatedNot excessively hyperbaric(PaCo2 50 mmHgFully recovered from MRSustained head liftStrong hand gripStrong tongue protrusion- Hypoxic (O2 saturation < 90 mmHg)- Excessively hyperbaric(Pa CO2 >50mm Hg- Hypothermic (< 34 C)- NMB present
33complete laryngospasm Partial laryngospasmcomplete laryngospasminspiratory stridorabsence of air movementTracheal tug and paradoxical (“see-saw”) movement of the abdomenIncreased airway problemschildren with a history of a recent upper respiratory tract infectionformer premature infantschildren with chronic, obstructive sleep apneaAnesthesiologists should anticipate increased airway problems in three groups of children:
34Managament of laryngospasm jaw thrust maneuver, neck extension and mouth openingmild biphasic snoring-noisy breathingplacing the child in the “safe” positionThe presence of secretions in the oropharynx may be responsible for these complications. However, data have not shown that extubating the trachea when the patient is fully awake leads to decreased hypoxemia compared to tracheal extubation while deeply anesthetizedoxygen by face maskpositive pressure with a bag and face mask may be requiredalong with a naso-pharyngeal airwayIf necessary a dose of succinylcholine followed by tracheal re-intubation (in children older than 2 years!!!)
35 Of particular concern have been the instances of life-threatening malignant hyperpyrexia and reports of rare, but often fatal, hyperkalaemic cardiac arrests in young boys with undiagnosed muscular dystrophy. As a result of these reports, in 1994, the US Food and Drug Administration (FDA) recommended that ‘the use of succinylcholine in children should be reserved for emergency intubation and instances where immediate securing of the airway is necessary, e.g. laryngospasm, difficult airway, full stomach, or for i.m. use when a suitable vein is inaccessible’. Since the publication of this recommendation, the use of succinylcholine in routine anaesthesia in children has been declined.
36RISK OF CARDIAC ARREST FROM HYPERKALEMIC RHABDOMYOLYSIS This syndrome often presents as peaked T-waves and sudden cardiac arrestwithin minutes after the administration of the drug in healthy appearingchildren (usually, but not exclusively, males, and most frequently 8 yearsof age or younger).There have also been reports in adolescents.
37Recent concerns about the elective use of succinylcholine in pediatric patients have focused on the occasional reports of hyperkalemic cardiac arrest, particularly in children with undiagnosed Duchenne muscular dystrophy. The incidence of Duchenne muscular dystrophy is only 1 in 3000 to 8000 male children. The revised labeling continues to permit the use of succinylcholine for emergency control of the airway and treatment of laryngospasm. Succinylcholine is the only neuromuscular blocking agent currently available that has been demonstrated to be effective after intramuscular (IM) administration when emergency control of the airway is required and there is no IV access. In this circumstance, the dosage must be increased to 4 to 5 mg/kg IM. Atropine is administered simultaneously. Following IM succinylcholine, onset of neuromuscular blockade takes approximately 2 to 5 minutes; the response in patients who are hypotensive or hypovolemic is unpredictable.
38In the Proposed Approach to the management of laryngospasm first of all is to think of:Airway irritation/obstructionBlood/secretionsLight anaesthesiaRegurgitation
39The main aim is to rapidly oxygenate child! 100% oxygen (warm, humidified,oxygen enriched air mixture in neonates)Visualize and clear pharynx/airwayJaw thrust with bilateral digital pressure behindtemporomandibular joint, oral/nasal airwayDeepen anaesthesia with propofol (20% induction dose)Succinylcholine 0.5 mg/kg to relieve laryngospasm( mg/kg i.v. or 4.0 mg/kg i.m. for intubationBe aware of use in children < 2 years old!!!Intubate and ventilate
40Airway obstruction in the postoperative period post-intubation croupLaryngeal edema - in neonates and infants = inspiratorystridor within 6 h of extubation (Subglottic edema of 1 mm in neonatescan reduce the laryngeal lumen by 35%)- Supraglottic oedema- Retroarytenoidal oedema- Subglottic oedemaAssociated risk factorsThe incidence seems to be decreasing as anesthesiologists have started to use smaller tracheal tubes and ensuring there is an air leak below cms water pressureHowever there are no enough evidences that cuffed tracheal tubes that have been used in small children increased incidence of croup. Perhaps the wider use of steroids during adeno-tonsillectomies, one of the pediatric operations with greater risk, may be a factor in the decrease in postintubation crouptight fitting tubetrauma at intubationduration of intubation >1 hcoughing on the tubechange of head and neck position during surgery
41Management of laryngeal edema warm, humidified, oxygen enriched air mixturenebulized epinephrine 1:1000 (0.5 ml kg−1 up to 5 ml)dexamethasone 0.25 mg kg−1 followedby 0.1 mg kg−1 six hourly for 24 hreintubation with a smaller tube in severe cases
42Conclusion● Upper airway obstruction (UAO) is a life-threatening emergency that requires prompt diagnosis and treatment● Severe UAO can be surprisingly asymptomatic at rest if it develops gradually. Sudden clinical deterioration is unpredictable● Patients with possible UAO must never be sedated until the airway is secured. Minimal sedation may precipitate acute respiratory failure● Achievement of airway patency in total airway obstruction and reestablishment of ventillatory airflow is the first and foremost goal of the anaesthesiologists
43Conclusion● Critical care physicians must be aware that pharmacologic interventions (epinephrine, steroids, and heliox) provide temporary support but cannot significantly improve mechanical UAO● Bronchoscopy constitutes the most accurate diagnostic tool and frequently provides the best way to correct UAO● Cricothyroidotomy is the surgical intervention of choice to reestablish airflow when medical interventions have failed
44ConclusionIf the anaesthesiologist is competent in the full range of airway access procedures and when appropriately management is performed, the possibility of incidence and consequences of acute airway obstruction in children will be very low