气道的评估和管理Airway-Evaluation-and-Management.ppt

Click To Edit Title Style,Click To Edit Title Style,*,Click To Edit Title Style,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,*,单击此处编辑母版文本样式,第二级,单击此处编辑母版标题样式,*,Airway Evaluation and Management,II.EVALUATION,A.History.A history of difficult airway management in the past may be the best predictor of a challenging airway.,1.Arthritis or cervical disk disease may decrease neck mobility.,2.Infections of the floor of the mouth,salivary glands,tonsils,or,pharynx,may,cause pain,edema,and trismus with limited mouth opening.,3.Tumors may obstruct the airway or cause extrinsic compression and,tracheal,deviation.,4.Morbid obesity is associated with difficult airway management.,II.EVALUATION,5.Trauma may be associated with airway injuries,cervical spine injury,basilar,skull fracture,or intracranial injury.,6.Previous surgery,radiation,or burns may produce scarring,contractures,and limited tissue mobility.,7.Acromegaly may cause mandibular hypertrophy and overgrowth and,enlargement of the tongue and epiglottis.,8.Scleroderma may produce skin tightness and decrease mandibular motion and,narrow the oral aperture.,II.EVALUATION,9.Trisomy 21 patients may have atlantoaxial instability and macroglossia.,10.Dwarfism,.,11.Other congenital anomalies may complicate,airway management,.,B,.Physical Examination,1.Specific findings that may indicate a difficult,airway include the following:,a.Inability to open the mouth.,b.Poor cervical spine mobility.,c.Receding chin(micrognathia).,II.EVALUATIONd.Large tongue(macroglossia).,e.Prominent incisors.,f.Short muscular neck.,2.Injuries to the face,neck,or chest must be evaluat,-,ed to assess their,contribution to airway compromise.,3.Head and neck examination.There is no single best predictor of difficult,airway management on the physical exam,so a detailed exam is in order.,4.The Mallampati classification,The modified classification includes the,following four,categories(Fig.13.1):,a.Class I.Faucial pillars,soft palate,and uvula are,visible.,b.Class II.Faucial pillars and soft palate may be seen,but the uvula is,masked,by the base of the tongue.,c.Class III.Only soft palate is visible.Intubation is,predicted to be difficult.,d.Class IV.Soft palate is not visible.Intubation is,predicted to be difficult.,III.MASK AIRWAY,A.Indications,1.To preoxygenate(denitrogenate)a patient before,endotracheal intubation.,2.To assist or control ventilation as part of initial,resuscitation before an ETT is,placed.,3.To provide inhalation anesthesia in patients,not,at risk for regurgitation of,gastric contents.,2.Mask placement.,with one hand with two hands,III.MASK AIRWAY,D.Complications.The mask may cause pressure,injuries to soft tissues around,the mouth,mandible,eyes,or nose.Loss of the airway may result from,laryngospasm or,vomiting.Mask ventilation does not,protect the airway from aspiration of gastric contents.,Laryngospasm,a tonic contraction of the laryngeal,and pharyngeal muscles,causes,airway obstruction,that may be relieved by jaw thrust,and the applica,-,tion of constant,positive airway pressure.If this fails,a,small dose of succinylcholine(20 mg,intravenously or,intramuscularly in the adult)may be required.,IV.LARYNGEAL MASK AIRWAY,1.Indications,a.As an alternative to mask ventilation or,endo,-,tracheal,intubation for airway,management.The,LMAis not a replacement for endotracheal intubation,when,endotracheal intubation is indicated.,b.In the management of a known or unexpected,difficult airway.,c.In airway management during the resuscitation of,an unconscious patient.,LMA,Insertion,2.Contraindications,a.Patients at risk of aspiration of gastric contents(,emergency use is an,exception).,b.Patients,with decreased respiratory system,compliance,because the,low-pressure seal of the,LMA cuff will leak at high inspiratory pressures and,gastric,insufflation may occur.Peak inspiratory,pressures should be maintained at less than 20cm,H2O to,minimize cuff leaks and gastric insufflation.,c.Patients in whom long-term mechanical ventilatory,support is anticipated or,required.,d.Patients with intact upper airway reflexes,because,insertion can precipitate,laryngospasm.,V.ENDOTRACHEAL INTUBATION,A.Orotracheal Intubation1.Indications.Endotracheal intubation is required to,provide a patent airway,when patients are at risk,for,aspiration,when airway maintenance by mask,is difficult,and for prolonged controlled ventilation.,Intubation also may be required for specific,surgical,procedures(e.g.,head/neck,intrathoracic,or intra-,abdominal procedures).,V.ENDOTRACHEAL INTUBATION,3.Complications of orotracheal intubation include,inury of the lips or tongue,teeth,pharynx,or,tracheal,mucosa.There may rarely be avulsion of,arytenoid cartilages,or damage to vocal cords or,trachea.,B.Nasotracheal Intubation,1.Indications.Nasotracheal intubation may be,required in patients undergoing anintraoral,V.ENDOTRACHEAL INTUBATION,procedure.Compared with oral ETTs,the maximal,diameter that can be,accommodated is usually,smaller,and,accordingly,the resistance to,breathing may be,higher.The nasotracheal,route is now rarely used for long-term intubation,because of,increased airway resistance and the,increased risk of sinusitis.,VI.THE DIFFICULT AIRWAY AND,EMERGENCY AIRWAYTECHNIQUE,S,2.The ASA defines a difficult airway as failure to,intubate with conventional,laryngoscopy after three,attempts and/or failure to intubate with conven,-,tional,laryngoscopy for more than 10 minutes.Others have suggested that a more appropriate,definition,of a difficult airway would be that of failure to,intubate with conventional,laryngoscopy after an,optimal/best attempt.,3.The use of regional anesthesia as a way to avoid,the known or anticipated,difficult airway deserves,special mention.,4.The LMA(Classic and Fastrach)is a prominent,airway option throughout the,2003 ASA difficult,airway,algorithm,.,B.Emergency Airway Techniques,1.Percutaneous needle cricothyroidotomy,2.Rigid bronchoscopy,3.Cricothyroidotomy,4.Tracheostomy,Case Report,A 48-yr-old,58-kg,woman was scheduled for,craniotomy because of a tumor around the third,ventricle.,-,After induction of anesthesia,nasotracheal,intubation with a 6.5 cuffed,-,ETT(endotracheal tube)was performed without difficulty under direct laryngoscopy.,-,The position of the ETT was confirmed and well secured over her right nostril at the26-cm mark.,Seven hours after induction,however,the end-tidal carbon dioxide tracing disappeared suddenly and the ventilator apnea pressure alarm was activated.,The ETT was then noted to be dislodged out of the patients right nostril.,After confirming ETT extubation,the surgical microscope was moved from the operating table and a sterile towel was immediately placed over the patients opened dura.,Manual ventilation of the lungs was attempted via a facemask,However,this was difficult because upper airway obstruction and the prone position with neck flexed.It was also difficult to depress the chin for introduction of an oropharyngeal airway.,Nasal fiberoptic bronchoscopy(FOB)was,attempted with the operator under the operating,table,which was difficult and uncomfortable,because limited space forced the operator to lie on,the floor to perform FOB.,The operating table was then elevated with,reverse Trendelenburg position and left-side tilt.,The operator then had enough space to,perform,FOB by sitting on the floor,Under FOB,the patients edematous larynx and vocal cord were visible.After visualizing the carina,the operator,advanced the ETT along with the fiberoptic bronchoscope,through her right nostril.,The tube position was confirmed by direct visualization and capnography.The airway was reestablished in 6 min.,During the process of emergency airway management,a,continuous high flow of oxygen was given via facemask,and the suction port of the fiberoptic bronchoscope,There was neither arterial desaturation nor hemodynamic,disturbance.,DISCUSSION,-,We demonstrated in this case that FOB can be suc,-,cessfully performed to guide the advancement of,an ETT into the trachea in this extremely flexed neck position.,For ease of FOB performance,the operating table should be elevated to its utmost height with reverse Trendelenburg position,The anatomic spatial relationship is comparable to FOB intubation with patients in the sitting position.,DISCUSSION,we also had a gurney available if the LMA or FOB failed and the patient desaturated.,A gurney is necessary to turn the patient into the lateral or supine position and release him/her from the Mayfield head holder if performing emergent tracheal intubation by direct,laryngoscopy,or even emergent cricothyroid-otomy.,Summary,When the patient is to be positioned prone,the anesthesiologist should anticipate and plan for the worst case scenario such as loss of the airway for any reason.,