NEJM VIDEOS IN CLINICAL MEDICINE: VIEWERS CHOICEAn exclusive collection of the most popular NEJM Videos in Clinical Medicine from the past year. BNEJM Videos in Clinical Medicine: viewers choiceEndotracheal Extubation01 The New England Journal of Medicine is a publication of NEJM Group, a division of the Massachusetts Medical Society.2015 Massachusetts Medical Society, All rights reserved.Reduction of Pulled Elbow14Ultrasound-Guided Insertion of a Radial Arterial Catheter10Insertion of an Intraosseous Needle in Adults05TABLE OF CONTENTSBack to Table of Contents1NEJM Videos in Clinical Medicine: viewers choice nejm.org n engl j med 370;3nejm.orgjanuary 16, 2014videos in clinical medicinesummary pointsThe newengl andjournalo f medicineThe following text summarizes information provided in the video.e4(1)Endotracheal ExtubationRafael Ortega, M.D., Christopher Connor, M.D., Ph.D.,Gerardo Rodriguez, M.D., and Caresse Spencer, M.D.From Boston Medical Center, Boston. Ad-dress reprint requests to Dr. Ortega at the DepartmentofAnesthesiology,Boston University Medical Center, 88 E. Newton St., Boston,MA02118,oratrafael.ortega@bmc.org.This article was updated on March 27, 2014, at NEJM.org.N Engl J Med 2014;370:e4.DOI: 10.1056/NEJMvcm1300964Copyright 2014 Massachusetts Medical Society.OverviewEndotracheal extubation refers to the removal of an endotracheal tube from the trachea. This procedure is commonly performed in operating rooms, postanesthesia care units, and intensive care units. This review focuses on extubation of the trachea after general anesthesia and short-term intubation; extubation after long-term intu-bation involves additional considerations that are beyond the scope of this review.Endotracheal tubes are initially placed to secure an airway for the adminis-tration of anesthetic agents, to provide airway protection, or to provide positive-pressure mechanical ventilation; these indications are not mutually exclusive. Once endotracheal intubation is no longer needed, extubation is indicated. However, the decision to extubate a patient must be made carefully, particularly because respira-tory and airway-related complications are more likely to occur after endotracheal extubationthanafterendotrachealintubation.Althoughmanyoftheproblems relatedtoendotrachealextubationareminor,seriouscomplicationscanarise. Thesecomplicationsincludecardiovascularstress,pulmonaryaspiration,hypox-emia, and even death. Respiratory failure can occur almost immediately or later after extubation.To minimize the possibility of complications related to the removal of an endo-tracheal tube, a plan for airway management is required. It is important to anticipate the possibilities of difficulties in airway management, cardiopulmonary instability, and the need to reintubate the trachea.IndicationsEndotrachealextubationisindicatedwhentheclinicalconditionsthatrequired airway protection with an endotracheal tube or that required mechanical ventilation are no longer present.Watch the video now.An internet connection is required to view this video.Back to Table of Contents2NEJM Videos in Clinical Medicine: viewers choice nejm.org e4(2)ContraindicationsEndotracheal extubation is contraindicated when the patients ability to protect the airwayisimpaired(i.e.,thepatientdoesnothaveprotectiveairwayreflexes)or when the patient cannot maintain adequate spontaneous respiration (i.e., the patient haspersistentweaknessintherespiratorymuscles,hypoxemia,orhypercarbia). Extubation may also be contraindicated in certain patients in the presence of cardio-vascular instability, metabolic derangements, or hypothermia.Quantitative values such as respiratory rate, tidal volume, and oxygen saturation are useful indicators of patient readiness for extubation, but all pertinent and avail-able information must be considered. Ultimately, good clinical judgment is required. Particularcautionisneededwhenthepatientsrequirementsforoxygenation, ventilation, or both are high, when the patient has a history of airway obstruction, or when there has been previous difficulty in ventilating or intubating the patient.Equipment and MedicationsEquipment selection is guided by the need to prevent complications and to main-tain airway patency, oxygenation, and ventilation. The equipment needed to con-tinuously monitor the patients vital signs should be on hand, as should a suction device for the removal of airway secretions. Supplemental oxygen and an appropri-ately sized face mask with a bag-valve device should also be close at hand. Oropha-ryngeal and nasopharyngeal airways should be readily available in case they are needed to improve airway patency. A laryngoscope, endotracheal tubes, and stylets should be on hand in case immediate reintubation of the trachea is necessary. An induction agent, such as propofol, and a muscle relaxant, such as succinylcholine, can facilitate emergency reintubation.If it is difficult to achieve ventilation with a face mask (Fig. 1), or if reintubation isdifficult,asupraglotticrescuedevice,suchasalaryngealmaskairway,may provide adequate oxygenation and ventilation. In the rare event that it is not pos-sible to ventilate or reintubate the patient after extubation, establishing immediate airway access by performing a cricothyroidotomy may be necessary.Routine ExtubationEndotrachealextubationisusuallyperformedwhenpatientsareawakeorhave emerged from general anesthesia. Make sure that adequate pain control is estab-lished. If the patient is awake, a visual-analogue scale can be used to determine whether the degree of analgesia is adequate. Cardiovascular stability, normal acidbase status, normothermia, and intact protective airway reflexes should be present. If neuromuscular blockade was induced, the blockade must be fully reversed.In preparation for extubation, the ventilator should be adjusted to ensure that adequate respiratory effort is present with minimal support. Oxygenation should be maximized, with 100% inspired oxygen delivered through the breathing circuit.Place the patient in a semirecumbent position to reduce the work of breathing and improve oxygenation; moving the patient from a supine to a semirecumbent position increases functional residual capacity, allowing for longer periods of ap-nea before oxygen desaturation occurs. Make sure that the tidal volume, respiratory rate, and inspiratory force are at appropriate levels before beginning extubation.Suction the patients endotracheal tube with a disposable catheter or an in-line suction device, and then carefully remove any tape or securing device in prepara-tion for extubation. Avoid inducing abrupt head and neck movements, which may cause the endotracheal tube to stimulate the trachea and trigger coughing. A pa-tientwithaninjurytothecervicalspinemayrequireadditionalnecksupport. The new england journal of medicinen engl j med 370;3nejm.orgjanuary 16, 2014Figure 1. Administration of Supple-mental Oxygen.Back to Table of Contents3NEJM Videos in Clinical Medicine: viewers choice nejm.org e4(3)Carefullysuctionanyoropharyngealsecretions(Fig.2),avoidingtraumatothe teeth and the airway. To minimize the risk that the patient will bite the endotra-cheal tube, which could cause occlusion of the tube or result in dental injury, a bite block or an oral airway may be used.Patients emerging from general anesthesia often make forceful, uncoordinated movements just before they are ready for extubation. Therefore, it is vital to protect the position of the endotracheal tube to keep the patient from accidentally self-extubating, which could cause hypoxemia. In addition, the patients fingernails or objects such as the pulse oximeter sensor could cause abrasions to the corneas if the patients arms and hands are not secured.When the patient is ready for extubation, attach a syringe to the pilot balloon andcompletelydeflatethecuffoftheendotrachealtube.Tomaximizealveolar recruitmentduringendotrachealextubation,positive-pressureventilationwith oxygencanbeprovidedwithabag-valvedevice.Afterextubation,immediately verify that the airway is patent and that adequate spontaneous ventilation is occurring. Observe the face mask for the rhythmic condensation of exhaled breath. Phonation and speech after extubation are reassuring signs that injury to the vocal cords and acute glottic edema have largely been prevented. Continue to provide supplemental oxygen through the face mask until the patient has fully recovered.Extubation of Morbidly Obese PatientsWhen extubating morbidly obese patients with obstructive sleep apnea, readiness to support ventilation and maintain airway patency are very important. Before ex-tubation, make sure the patient is fully awake and able to respond appropriately to commands. Upright positioning of the patient is strongly recommended so that the excess body tissue on the chest and against the diaphragm is displaced caudad, which will reduce the work of breathing and increase the functional residual capacity. Afterextubation,thepatientshouldbekeptinasemirecumbentpositionand should be monitored closely for acute airway obstruction.Difficult ExtubationThe extubation of patients in whom intubation or the placement of a face mask was difficultrequiresspecialconsideration,becausemanagingtheconsequencesof unsuccessful extubation can be extremely challenging. Surgical factors (e.g., the need for a patient to spend a long time in the prone position or the need for direct surgical manipulation of the airway) and medical factors (e.g., angioedema) may increase the difficulty of airway ventilation or intubation. If continued intubation is deemed safer than mechanical ventilation, adequate sedation and cardiopulmo-nary monitoring should be maintained. The plan should be documented and clear-ly communicated to the patients medical team.Serious Complications of ExtubationAlthough few extubation-related complications are life-threatening, hypoxemia is the common pathway to severe complications. In the period immediately after ex-tubation, early respiratory insufficiency may be caused by poor ventilation or resid-ual neuromuscular blockade. Bronchospasm and severe coughing can also impair adequate ventilation and can be treated with topical or intravenous local anesthetic agents, intravenous opioids, or bronchodilators, as indicated. Acute upper-airway obstruction may be caused by laryngospasm, especially in children. Vocal-cord dys-function is a rare cause of airway obstruction and sometimes requires immediate reintubation.Thepossibilityofvocal-corddysfunctionshouldbeinvestigatedif Endotracheal Extubationn engl j med 370;3nejm.orgjanuary 16, 2014Figure 2. Suctioning of the Oropharynx.Back to Table of Contents4NEJM Videos in Clinical Medicine: viewers choice nejm.org e4(4)there is a suspicion of injury to the recurrent laryngeal nerves. Patients with laryn-geal edema due to prolonged intubation or direct compression of the glottis can present with delayed airway obstruction and inspiratory stridor. Impairment of the airway and swallowing reflexes can pose a risk of pulmonary aspiration. Manipula-tionoftheairwayisusuallynoxiousforpatients,causingincreasedmyocardial demand; pretreatment with opioids or beta-blockers can reduce this catecholamine-mediated stress. If the medical indications that led to intubation have not been adequately resolved, progressive decompensation may occur after extubation, ulti-mately leading to reintubation. A tracheostomy is indicated if safe extubation can-not be achieved in 7 to 14 days.SummaryEndotracheal extubation should be performed without causing trauma, while main-tainingadequateoxygenationandventilation.Theequipmentneededtoprovide suction, ventilation, and reintubation should be readily available. If extubation is judged to be unsafe, the procedure should be postponed and the patient reevaluated. Most complications related to extubation are preventable.Before performing extubation, the clinician must carefully prepare the medical resources needed to address reasonably foreseeable complications. A failed extubation can lead to a precipitous deterioration in the patients condition, and attempts to improvise solutions under these challenging circumstances are rarely satisfactory.No potential conflict of interest relevant to this article was reported.Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.Copyright 2014 Massachusetts Medical Society.EndotrachealExtubationn engl j med 370;3nejm.orgjanuary 16, 2014Back to Table of Contents5NEJM Videos in Clinical Medicine: viewers choice nejm.org videos in clinical medicinesummary pointsThe newengl andjournalo f medicineThe following text summarizes information provided in the video.Insertion of an Intraosseous Needlein AdultsShelly P. Dev, M.D., Raluca A. Stefan, M.D., Tomas Saun, B.Sc.,and Shirley Lee, M.D.From the Sunnybrook Health Sciences Cen-tre, University of Toronto, Toronto. Address reprint requests to Dr. Dev at the Depart-ment of Critical Care Medicine, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., D112, Toronto, ON M4N 3M5, Canada, or at shelly.dev@sunnybrook.ca.N Engl J Med 2014;370:e35.DOI: 10.1056/NEJMvcm1211371Copyright 2014 Massachusetts Medical Society.OverviewObtaining rapid vascular access is an essential step in the resuscitation of critically ill patients. Peripheral or central intravenous access may be difficult to obtain in a timelymannerinsuchpatients,especiallyinchildrenandneonatesbutalsoin adult patients, in whom the vessels may be constricted. Obtaining peripheral intra-venous access is especially challenging when environmental conditions are unfa-vorable (e.g., before a patients arrival at a hospital, during mass casualty events, or during military operations).1-3 Central intravenous access carries the risk of pneu-mothoraxandarterialinjuryandrequiresahighlevelofexpertise;inmostin-stances, it is not possible to perform the procedure in a prehospital setting.1 The insertion of an intraosseous needle provides an alternative route for vascular access in these circumstances; it is also used after other approaches have failed. Although intraosseous needle insertion was originally performed in the resuscitation of pe-diatric patients, it has gained acceptance for use in adults, especially since the ad-vent of mechanical insertion devices.1,3-9 The video focuses on intraosseous inser-tion in adult patients.The most recent guidelines from the Advanced Cardiac Life Support Certifica-tion Institute, published in 2010, recommend the intraosseous route over the en-dotracheal route for the administration of fluids and medications in adult patients in whom intravascular access is not available.6 The primary advantages of the in-traosseous route are speed of access and reliability.3IndicationsIntraosseous access is indicated for patients in whom there is an urgent need for vascular access in order to provide fluid resuscitation or medication delivery and in Watch the video now.An internet connection is required to view this video.Back to Table of Contents6NEJM Videos in Clinical Medicine: viewers choice nejm.org e35(2)whom conventional venous access is not readily available. Cardiac arrest, shock, trauma,extensiveburns,severedehydration,andstatusepilepticusarepossible clinical scenarios in which intraosseous access may be needed.2 Intraosseous ac-cess has been used successfully for situations in which adverse environmental con-ditions make it very difficult to obtain intravenous access (e.g., search-and-rescue and military operations).1,2 This technique is also useful when central venous ac-cess is not feasible because of either lack of provider expertise or lack of equipment (e.g., in prehospital settings).1Crystalloids,colloids,bloodproducts,andmanymedicationsincluding drugsusedforresuscitationandvasopressorinfusionscanbeadministered through the intraosseous route,3 and the doses are the same as those used when intravenous access has been established.6 In addition, in the critically ill patient, a sample can be drawn from the intraosseous space for laboratory testing (e.g., bloodtyping,measurementofhemoglobinlevel,serumchemicalanalysis,and bloodgasanalysis).Thebloodgasesfrommarrowsamplesaretypicallyatan intermediatelevelbetweenarterialandvenouslevels.10Somediscrepanciesbe-tween intraosseous and venous samples have been found in alkaline phosphatase, lactatedehydrogenase,andhemoglobinlevels.Whenintraosseoussampleswere collected after the infusion of fluids through the site and after 30 minutes of car-diopulmonary resuscitation, hemoglobin levels were shown to be lower than the levels in the central circulation.11ContraindicationsSince intraosseous insertion is used only in emergencies, there are few contraindi-cations to placement. Contraindications include ipsilateral fractures, previous at-temptsatipsilateralintraosseousaccess,localvascularinjuries,cellulitis,and burns.2,3 Ipsilateral fracture or previous attempts at intraosseous access can lead to fluid extravasation and compartment syndrome and should thus be avoided.2,3 In-traosseous insertion should be avoided in patients with a high risk of fracture (e.g., patients with osteogenesis imperfecta, severe or advanced osteoporosis, or coagu-lopathies).2AnatomyThe medullary cavity is a highly vascular structure that functions as a noncollaps-ible vein capable of accepting a large volume of fluid and medications and rapidly delivering them to the central circulation (Fig. 1). The medullary venous sinusoids drain into a central venous channel, which exits the bone in the form of emissary and nutrient veins. The rate of infusion is limited by the size of the medullary cav-ity and the diameter of the intraosseous needle.Site SelectionA number of sites can be used for intraosseous needle insertion in an adult, such as the proximal tibia, the distal tibia, the humerus, the distal femur, the sternum, the calcaneus, and the styloid of the radius.1-3 When a mechanical insertion device is used, the anteromedial surface of the proximal tibia is the preferred site of inser-tion because it is easy to locate, presents a flat and wide surface for insertion, and has minimal subcutaneous layers overlying the bone.3 In addition, this site has the benefit of being distant from the patients chest and thus will pose minimal inter-ference with cardiopulmonary resuscitation. If it is not possible to obtain intraos-seous access through the proximal tibia, the humeral head and distal tibia are al-ternative sites.The new england journal of medicinen engl j med 370;24nejm.orgjune 12, 2014Figure 1. Drainage of the Medullary and Venous Sinusoids into the Central Venous Channel, with Penetrationof the Intraosseous Needle intothe Medullary Cavity.Back to Table of Contents7NEJM Videos in Clinical Medicine: viewers choice nejm.org e35(3)If the intraosseous needle is inserted manually, the medial aspect of the distal tibiaisthepreferredsiteinadultpatientsbecauseofitsthinbonecortexand overlyingtissue.2Asubstantialamountofforceandalarge-boreneedlearere-quired to manually penetrate the bone.The sternum is another alternative site.3 A specific mechanical system for in-traosseous needle insertion system facilitates needle insertion with minimal risk ofperforationorinfectionofmediastinalstructures.Althoughthethinbone cortex makes this the easiest site for manual insertion in adults, it does carry a small risk of perforation of mediastinal structures and is thus not favored. Addi-tional impediments to use include risk of dislodgement during cardiopulmonary resuscitation and interference with cardiopulmonary resuscitation. This technique is not described in the video.Preparation for Mechanical InsertionThe following items should be assembled in preparation for the drill-based inser-tion:chlorhexidineoriodinesolutionforsitepreparation,sterilegloves,sterile towels for draping the site, a kit for mechanical device insertion, a 10-cc syringe for aspiration and infiltration, a solution of 1% lidocaine for analgesia if the patient is conscious, standard Luer-Lok tubing for the delivery of fluids or medication, a pres-sure bag if large volumes of fluid need to be administered through the intraosseous system, and gauze and tape for securing the device.In adults, the use of mechanical drill-assisted insertion devices facilitates in-traosseous needle insertion, although manual insertion is also possible. Mechani-cal devices developed for intraosseous access placement and approved by the Food andDrugAdministrationaretheFAST-1IntraosseousInfusionSystem(Pyng Medical) for sternal intraosseous access, the EZ-IO drill (Vidacare), and the Bone Injection Gun (Waismed).9 The use of a drill-assisted mechanical insertion device is described in the video.Intraosseous Needle Insertion with a Mechanical DeviceObtaining intraosseous access is an emergency procedure. Consequently, it is rare-ly possible to obtain informed consent before performing the procedure. If possi-ble, explain the risks and benefits of the procedure to the patient or the next of kin; otherwise, proceed with insertion.When a mechanical device is used, the proximal tibia is the preferred site in adults. Secondary sites are the distal tibia and the humeral head.Position the patients leg in slight flexion by placing a rolled towel under the knee. Don sterile gloves, expose and clean the site with chlorhexidine or iodine solution, and then drape the site in a sterile fashion. If the patient is conscious, infiltrate the skin and subcutaneous tissues and the periosteum with 20 to 30 mg of 1% lidocaine.Identify the tibial tuberosity. The desired insertion site is the flat medial surface of the tibia, medially one fingers width away from the tibial tuberosity (Fig. 2). Stabilize the leg with your nondominant hand. Holding the drill in your dominant hand, position the needle tip at a 90-degree angle to the surface of the bone. Press andholdthetriggerandgentlyguidetheneedlethroughthetissues,avoiding excess pressure. A sudden loss of resistance indicates that the needle has penetrat-ed the cortex and has reached the medullary cavity.Removethestyletandconnecttheneedletoa10-ccsyringewithstandard Luer-Loktubing.Iftheneedleiscorrectlyplacedwithinthemarrowcavity,it should be possible for it to stand upright without support. Aspiration of blood and intraosseousneedleinsertioninanadultn engl j med 370;24nejm.orgjune 12, 2014Figure 2. The Desired Site for Mechani-cal Intraosseous Needle Insertion.The ideal mechanical insertion siteis the flat medial surface of the tibia, medially one fingers width away from the tibial tuberosity.Back to Table of Contents8NEJM Videos in Clinical Medicine: viewers choice nejm.org The new england journal of medicinen engl j med 370;24nejm.orgjune 12, 2014marrow confirms adequate placement of the needle, but it is not always possible to aspirate marrow, even with adequate placement. Obtain confirmation of place-ment by infusing a 10-cc bolus of saline solution through the syringe; the fluid should flow easily, with no resistance. If the fluid does not flow, select another insertion site.Aftercorrectplacementhasbeenconfirmed,thetestsyringecanbediscon-nected and the intraosseous needle can be connected to regular infusion tubing. Fluids can be infused by means of gravity, but infusing fluids through a pressure bag produces better flow rates. A pressure bag should be used in patients requir-ing resuscitation, once you are certain that the needle has been correctly placed and is functioning. If the patient is conscious, anesthetize the marrow cavity by infusing 20 to 40 mg of 1% lidocaine before initiating the infusion. While infusing fluids,watchcarefullyforextravasationandincreasedcalfcircumference.The needle and tubing should be secured to the leg with tape, and the leg should be immobilized to prevent dislodgement of the needle.To remove the catheter, disconnect the intravenous tubing and attach a sterile syringe to the hub. Stabilize the leg, and gently pull back while rotating the needle clockwise.Preparation for Manual InsertionThe following items should be assembled in preparation for the manual insertion ofanintraosseousneedle:chlorhexidineoriodinesolutionforsitepreparation, sterile gloves, sterile towels for draping the site, an intraosseous needle, a 10-cc syringe for aspiration and infiltration, a solution of 1% lidocaine for analgesia if the patient is conscious, standard Luer-Lok tubing for the delivery of fluids or medica-tion, a pressure bag if large volumes of fluid need to be administered through the intraosseous system, and gauze and tape for securing the device.Several different types of needles can be used in manual intraosseous insertion. They all have in common the presence of a stylet, which improves the likelihood of cortical penetration and prevents plugging of the needle cavity with bone spic-ules during insertion.12 They range in size from 13-gauge to 20-gauge and have variable lengths and handle types. A depth marker or an adjustable sleeve allows for better control of penetration depth. A shorter shaft and a smaller handle are desirable features, since they allow for better control.2Manual Intraosseous Needle InsertionThe preferred site for manual insertion in adults is the medial aspect of the distal tibia, just proximal to the medial malleolus (Fig. 3). Position the leg so that it is in slight flexion and externally rotated at the hip. As described earlier for mechanical insertion, use sterile technique and appropriate analgesia. Stabilize the leg with the nondominant hand. Hold the needle in the palm of the dominant hand and posi-tion it at a 90-degree angle to the long axis of the bone. Advance the needle through the bony cortex with a twisting or rotating motion and steady pressure; you will encounter a great deal of resistance.A sudden loss of resistance indicates that the needle has penetrated the cortex and reached the medullary cavity. Remove the stylet and connect a 5-cc or 10-cc syringe to the needle. Obtain confirmation of placement by infusing a 10-cc bolus of saline solution through the syringe; the fluid should flow easily, with no resis-tance. If the fluid does not flow easily, the needle can be repositioned by pulling backslightly,butiffurtherresistanceisencountered,theneedleshouldbere-moved and a new site selected. You can avoid through-and-through penetration of e35(4)Figure 3. The Desired Site for Manual Intraosseous Needle Insertion.The preferred site for manual inser-tion in adults is the medial aspect of the distal tibia, just proximal to the medial malleolus.Back to Table of Contents9NEJM Videos in Clinical Medicine: viewers choice nejm.org n engl j med 370;24nejm.orgjune 12, 2014intraosseousneedleinsertioninanadultthebonebyusingthedepthmarkingsontheneedleandbyplacingtheindex finger about 1 cm from the bevel of the needle. Secure the needle with bulky gauze dressing and tape.ComplicationsComplications can occur during the course of the procedure or even after success-ful placement of the intraosseous needle. Notable morbidity has been quoted at less than 1% for all occurrences combined.4 The most common complication of intraos-seous needle insertion is fluid extravasation resulting from through-and-through penetration of the bone or from incomplete insertion of the needle. If extravasation occurs, the needle should be removed and pressure should be applied to the site. Compartment syndrome is a rare but possible complication of fluid extravasation that may occur when a needle has been placed incorrectly. Bone spicules may cause blockage of the needle; to prevent blockage, the line should be flushed with 3 to 5 cc of saline every 15 minutes.Othercomplicationsduringinsertionincludesubcutaneousorsubperiosteal infiltration due to incomplete insertion. Fracture of the long bones has also been reported after intraosseous needle insertion; the risk increases if the patient has a disorder associated with a predisposition to bone fragility.4 Dislodgement of the needle and infiltration of large amounts of fluid in the interstitial space may lead to compartment syndrome.Despite adequate placement of the needle, the following complications may also occur: infection (cellulitis or osteomyelitis), fat embolus (reported in animal mod-elsbutnotofclinicalsignificance),localhematoma,pain,andcompartment syndrome.4,13 The reported rate of infection is lower than 3%, and a large litera-turereviewindicatesthattheincidenceofprocedure-relatedosteomyelitisis 0.6%.14 Local inflammation of the bone or necrosis of the skin at the insertion site may also occur; it is more common when hypertonic or sclerosing agents are infiltrated.2SummaryIntraosseous needle insertion is used as a temporary measure when intravascular access cannot be achieved through peripheral or central venous routes. The intra-osseousneedlemayremaininsitufor72to96hours,butitisbestremoved within 6 to 12 hours, as soon as an alternative site of intravascular access has been established.Theintraosseousrouteprovidesfastandreliablevascularaccessin emergency medical situations. The use of the appropriate technique will ensure that the procedure is performed as safely and effectively as possible.No potential conflict of interest relevant to this article was reported.Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.e35(5)References1.Schwartz D, Amir L, Dichter R, Figen-bergZ.Theuseofapowereddevicefor intraosseousdrugandfluidadministra-tion in a national EMS: a 4-year experience. J Trauma 2008;64:650-4.2.StanleyR.Intraosseousinfusion.In: RobertsJR,HedgesJR,ChanmugamAS, Chudnofsky CR, Custalow CB, Dronen SC, eds.Clinicalproceduresinemergency medicine. 4th ed. Philadelphia: Saunders, 2004:475-85.3.FowlerR,GallagherJV,IsaacsSM, Ossman E, Pepe P, Wayne M. The role of intraosseous vascular access in the out-of-hospital environment (resource document toNAEMSPpositionstatement).Prehosp Emerg Care 2007;11:63-6.4.Blumberg SM, Gorn M, Crain EF. In-traosseous infusion: a review of methods andnoveldevices.PediatrEmergCare 2008;24:50-6.5.Horton MA, Beamer C. Powered intra-osseous insertion provides safe and effec-tive vascular access for pediatric emergen-cypatients.PediatrEmergCare2008;24: 347-50.6.Neumar RW, Otto CW, Link MS, et al. Part 8: adult advanced cardiovascular life support 2010 American Heart Associa-tionguidelinesforcardiopulmonaryre-suscitation and emergency cardiovascular care science. Circulation 2010;122:Suppl 3: S729-S767.7.Davidoff J, Fowler R, Gordon D, et al. Clinical evaluation of a novel intraosseous device for adults: prospective, 250-patient, multi-center trial. JEMS 2005;30:Suppl:20-3.8.Olaussen A, Williams B. Intraosseous access in the prehospital setting: literature review. Prehosp Disaster Med 2012;27:468-72.9.Leidel BA, Kirchhoff C, Braunstein V, Bogner V, Biberthaler P, Kanz KG. Compari-son of two intraosseous access devices in adultpatientsunderresuscitationinthe emergency department: a prospective, ran-domized study. Resuscitation 2010;81:994-9.10.Orlowski JP, Porembka DT, Gallagher JM,VanLenteF.Thebonemarrowasa sourceoflaboratorystudies.AnnEmerg Med 1989;18:1348-51.11.Johnson L, Kissoon N, Fiallos M, Ab-delmoneim T, Murphy S. Use of intraosse-ous blood to assess blood chemistries and hemoglobinduringcardiopulmonaryre-suscitation with drug infusions. Crit Care Med 1999;27:1147-52.12.Orlowski JP. Emergency alternatives to intravenous access: intraosseous, intratra-cheal, sublingual, and other-site drug ad-ministration. Pediatr Clin North Am 1994; 41:1183-99.13.Buck ML, Wiggins BS, Sesler JM. Intra-osseous drug administration in children and adults during cardiopulmonary resuscita-tion. Ann Pharmacother 2007;41:1679-86.14.RosettiVA,ThompsonBM,MillerJ, MateerJR,AprahamianC.Intraosseous infusion: an alternative route of pediatric intravascular access. Ann Emerg Med 1985; 14:885-8.Copyright 2014 Massachusetts Medical Society.Back to Table of Contents10NEJM Videos in Clinical Medicine: viewers choice nejm.org videos in clinical medicinesummary pointsThe newengl andjournalo f medicineThe following text summarizes information provided in the video.Ultrasound-Guided Insertionof a Radial Arterial CatheterJonathan Ailon, M.D., Ophyr Mourad, M.D., Vince Chien, M.D.,Tomas Saun, B.Sc., and Shelly P. Dev, M.D.From the University of Toronto, Toronto. AddressreprintrequeststoJonathan Ailon,M.D.,DepartmentofGeneralIn-ternalMedicine,St.MichaelsHospital, 30 Bond St., 4CC-146, Toronto, ON M5B 1W8, Canada, or at ailonj@smh.ca.N Engl J Med 2014;371:e21.DOI: 10.1056/NEJMvcm1213181Copyright 2014 Massachusetts Medical Society.OVERVIEWInsertion of a radial arterial catheter is a common procedure in critical care units. Ultrasonography may be used to ensure safe and successful insertion of an arterial catheter. The video demonstrates the use of ultrasound guidance for radial arterial catheterization in adults with the over-the-needle approach in the transverse and longitudinal planes.INDICATIONSArterialcatheterizationallowsforthecontinuousrecordingofarterialpressure measurementsandcanbeusedtoadjustthedosesofvasoactivedrugsthatare administered for hemodynamic support in critically ill patients. Arterial catheter-ization also provides easy and convenient access to arterial blood when sampling of arterial blood gases and other laboratory tests need to be performed.Theradialarteryisthepreferredsiteforcatheterization.Becausetheradial artery is easily accessible, catheterization is associated with a low rate of complica-tions.1Theinsertionofthecatheterbymeansofablindpalpationtechnique, withoutultrasoundguidance,sometimesrequiresmultipleattemptsandthus contributes to patient discomfort and predisposes the patient to bleeding and arte-rial spasm. Successful arterial catheterization can be challenging in patients who are obese and in patients with edema, hypotension, or vascular anomalies, such as tortuous vessels.2 Ultrasound guidance can be more effective than palpation for the insertion of a radial arterial catheter in such patients.There is increasing recognition that the risks associated with performing blind bedside procedures are substantial.3 Point-of-care ultrasonography, defined as ultra-sonography brought to the patient and performed by the provider in real time, can enhance diagnostic and procedural accuracy.4 Point-of-care ultrasonography can also decrease patient anxiety and discomfort and can reduce procedure-related complications.4-6Watch the video now.An internet connection is required to view this video.Back to Table of Contents11NEJM Videos in Clinical Medicine: viewers choice nejm.org e21(2)In general, the use of ultrasound guidance for the insertion of a radial arterial catheter takes less time than the palpation method and has a higher success rate. In addition, successful insertion is achieved after fewer attempts,7-9 which means that there are fewer sites of attempted insertion and less patient discomfort.CONTRAINDICATIONSThere are no contraindications to the use of ultrasound guidance. However, radial arterial catheterization is contraindicated in patients with infection of the skin or soft tissue at the insertion site, severe peripheral vascular disease, impaired collat-eral circulation, or severe coagulopathy.10EQUIPMENT AND PREPARATIONAfter obtaining the patients consent to perform the procedure, gather the neces-sary equipment. You will need two pairs of sterile gloves, a mask, a sterile gown, a skin-preparation solution such as chlorhexidine, sterile drapes, 1% lidocaine with-out epinephrine, a 5-cc syringe and a 25-gauge needle for delivery of the local an-esthetic, and angiocatheters. Radial arterial catheterization can be performed with standardangiocathetersorwithsafetyangiocatheters.Usetheequipmentthat complies with the safety practices at your institution. You will need materials for dressing and securing the catheter, sterile gauze, and a sterile ultrasound probe cover with sterile gel. You will also need a pressure bag, a pressure transducer, and a monitor that is appropriate for arterial catheter transduction. In order to assess the vasculature, you will need a linear-array transducer ultrasound probe with a frequency range of 5 to 13 MHz.Wash your hands before touching the patient, and put on the mask. Position the patients wrist such that the forearm is flat. Put on a pair of sterile gloves, and use antiseptic solution to wash the skin of the patients forearm from the wrist to the antecubital fossa. Discard the gloves, wash your hands again, and put on the gown and a new pair of sterile gloves. Drape the patient, exposing only the cleaned forearm from the wrist to the antecubital fossa.STERILE TECHNIQUE WITH ULTRASONOGRAPHYHave an assistant clean the ultrasound transducer with an antiseptic wipe. Apply sterile gel to the inside of the sterile sheath and cover the ultrasound probe without contaminating the sterile gloves or the sheath. Remove any air pockets from around the probe, which, if present, will cause poor-quality ultrasound images.CHOOSING AN INSERTION SITEVascular assessment is typically performed with a linear array transducer operating at frequencies between 5 and 13 MHz. Make sure that the left side of the ultrasound probe corresponds to the left side of the screen. Starting at the patients wrist, scan the lateral aspect of the forearm in the transverse orientation and identify the ra-dial artery and the associated veins, which will be located between the styloid por-tionoftheradiusandtheflexorcarpiradialistendon.Ifnecessary,applylight pressure to help differentiate the artery from the veins; veins will collapse, whereas the artery will not (Fig. 1).Once the radial artery has been identified, have the assistant adjust the gain to optimize the contrast between the black vessels and the surrounding structures. Next, adjust the depth so that the artery appears in the center of the ultrasound screen and is clearly visible. As you scan the artery from the wrist to the antecu-bitalfossa,lookforarterialtortuosityandcalcification.Locateasectionofthe artery with a large diameter and minimal calcification.The new england journal of medicinen engl j med 371;15nejm.orgoctober 9, 2014ABFigure 1. The Use of Compressionto Differentiate Artery from Vein.The radial artery (Panel A, yellow arrow) is shown in the transverse orientation along with associated veins (white arrows). The application of light pres-sure with the ultrasound probe results in the collapse of the veins but not the artery, which can still be visual-ized (Panel B, arrow).Back to Table of Contents12NEJM Videos in Clinical Medicine: viewers choice nejm.org e21(3)To prevent the development of kinks in the catheter after it has been inserted, choose a site that is proximal to the wrist and distal to the elbow. Kinking can occur when the patient moves or is repositioned.CATHETER INSERTION IN THE TRANSVERSE ORIENTATIONAfter locating an appropriate site for catheterization, slide the probe so that the artery is centered on the screen. After anesthetizing the skin, insert the angiocath-eter-covered needle at the middle of the probe at an angle of 45 to 60 degrees. Slide or tilt the probe toward the needle tip until you can visualize the tip on the monitor. Make small bouncing movements with the needle to locate the tip.As you advance the needle toward the artery, tilt the probe in the direction of the needles trajectory to ensure that you can see the needle tip at all times. Repo-sition the tip periodically to confirm that it is directly above the artery.Insert the needle tip into the arterial lumen and examine the angiocatheter for flashback(Fig.2),orbloodreturn,inordertoconfirmitsposition.Flattenthe angle of the angiocatheter, and then reexamine the area on the ultrasound moni-tor to make sure that the needle tip is still in the artery.Slidethecatheterovertheneedleintothearteriallumen.Applypressure proximal to the catheter, remove the needle, and attach the catheter to the trans-ducer.CATHETER INSERTION IN THE LONGITUDINAL ORIENTATIONThe catheter can also be inserted in the longitudinal orientation (Fig. 3). Begin the procedure with the ultrasound probe in the transverse orientation to locate the ar-tery. Center the artery on the ultrasound screen and then rotate the probe 90 de-grees. You should see the artery in the center of the screen, with a view along its long axis, at its maximum diameter.Insert the angiocatheter at an angle of 15 to 30 degrees at the exact midline of thelongaxisoftheprobe.Advancetheneedleparalleltothelongaxisofthe probe.If you do not see the needle, it is probably medial or lateral to the vessel. Pull back on the needle without withdrawing it completely or letting it leave the skin, and readjust the angle so that you can see the needle tip on the ultrasound screen. Then advance the needle again, until it is within the lumen of the vessel, and look for flashback in the angiocatheter.Slide the catheter over the needle and into the arterial lumen. Apply pressure proximal to the catheter, remove the needle, and attach the catheter to the trans-ducer.COMPLICATIONSThe main challenges when performing ultrasound-guided catheterization are visu-alizationoftheneedletipanddifferentiationoftheneedletipfromtheneedle shaft, since each will appear as a white dot on the screen (Fig. 4). Novice operators sometimes believe that they are visualizing the needle tip on the monitor when they are actually viewing the needle shaft. In such instances, the unseen needle tip has beeninsertedmoredeeplythantheoperatorassumesandcancauseinjuryto deeperstructures.Forthisreason,continuousvisualizationoftheneedletipis crucial during angiocatheter insertion.Anotherchallengeduringarterialcatheterizationisarterialspasm,which may prevent the operator from advancing the catheter into the arterial lumen. Ifarterialspasmoccurs,useultrasoundguidancetofindamoreproximal site for insertion or consider arterial catheterization of the radial artery in the other arm.Ultrasound-GuidedInsertionofaRadialArterialCathetern engl j med 371;15nejm.orgoctober 9, 2014Figure 4. Identification of the Needle Tip and the Needle Shaft.A white dot on the ultrasound screen represents either the needle tip or the needle shaft. In the illustration and the ultrasound image, the angiocatheter has traversed the radial artery and has been inserted more deeply than the operator assumes. The needle shaft (white arrows) rather than the needle tip (yellow arrow) is visualized on the ultrasound screen.AB16p6AUTHOR Ailon FIGURE 3a&bJOB:ISSUE:4-CH/TRETAKE 1st2ndSIZEICMCASEEMailLineH/TComboRevisedAUTHOR, PLEASE NOTE: Figure has been redrawn and type has been reset.Please check carefully.REG FFILLTITLE3rdEnonARTIST:10-9-14mst37114Figure 3. Ultrasound-Guided Catheter-ization in the Longitudinal Orientation.The ultrasound probe is in the longi-tudinal orientation (Panel A) as the needle tip is inserted into the radial artery and visualized (Panel B, arrow).ABFigure 2. Ultrasound-Guided Catheter-ization in the Transverse Orientation.The ultrasound probe is in the trans-verse orientation (Panel A) as the needle tip is inserted into the radial artery and visualized (Panel B, arrow).Back to Table of Contents13NEJM Videos in Clinical Medicine: viewers choice nejm.org e21(4)SUMMARYIt is easy to learn how to use ultrasound guidance when performing radial arterial catheterization in either the transverse or the longitudinal orientation. Clinicians who regularly insert arterial catheters should master this technique because it can increase the success rate and reduce the number of attempts required for successful catheterization as compared with the palpation technique.No potential conflict of interest relevant to this article was reported. Disclosure forms provided by the authors are available with the full text of this article at NEJM.org.Ultrasound-GuidedInsertionofaRadialArterialCathetern engl j med 371;15nejm.orgoctober 9, 2014References1.Scheer B, Perel A, Pfeiffer UJ. Clinical review: complications and risk factors of peripheral arterial catheters used for hae-modynamicmonitoringinanaesthesia andintensivecaremedicine.CritCare 2002;6:199-204.2.Hofmann LJ, Reha JL, Hetz SP. Ultra-sound-guidedarteriallinecatheteriza-tioninthecriticallyill:techniqueand review. J Vasc Access 2010;11:106-11.3.KohnKT,CorriganJM,Donaldson MS.Toerrishuman:buildingasafer health system. Washington, DC: National Academy Press, 1999.4.Moore CL, Copel JA. Point-of-care ul-trasonography.NEnglJMed2011;364: 749-57.5.McGeeDC,GouldMK.Preventing complications of central venous catheter-ization. N Engl J Med 2003;348:1123-33.6.Feller-Kopman D. Ultrasound-guided thoracentesis. Chest 2006;129:1709-14.7.ShiverS,BlaivasM,LyonM.Apro-spective comparison of ultrasound-guid-ed and blindly placed radial arterial cath-eters. Acad Emerg Med 2006;13:1275-9.8.Levin PD, Sheinin O, Gozal Y. Use of ultrasoundguidanceintheinsertionof radialarterycatheters.CritCareMed 2003;31:481-4.9.ShilohAL,SavelRH,PaulinLM, Eisen LA. Ultrasound-guided catheteriza-tion of the radial artery: a systematic re-viewandmeta-analysisofrandomized controlled trials. Chest 2011;139:524-9.10.Tegtmeyer K, Brady G, Lai S, Hodo R, BranerD.Videosinclinicalmedicine: placementofanarterialline.NEnglJ Med 2006;354(15):e13.Copyright 2014 Massachusetts Medical Society.Back to Table of Contents14NEJM Videos in Clinical Medicine: viewers choice nejm.org videos in clinical medicinesummary pointsThe newengl andjournalo f medicineReduction of Pulled ElbowMegan Aylor, M.D., JoDee M. Anderson, M.D., Paula Vanderford, M.D.,Matthew Halsey, M.D., Susanna Lai, M.P.H., and Dana A.V. Braner, M.D.FromtheOregonHealthandScience University,Portland.Addressreprintre-queststoDr.BranerattheDepartment of Pediatrics, Oregon Health and Science University, 707 S.W. Gaines Rd., CDRC-P, Portland,OR97239,oratbranerd@ohsu.edu.N Engl J Med 2014;371:e32.DOI: 10.1056/NEJMvcm1211809Copyright 2014 Massachusetts Medical Society.OverviewPulled elbow, also known as annular ligament displacement or radial-head sublux-ation, is a common orthopedic injury in children.1 In the United States, the inci-dence of emergency department visits for pulled elbow is estimated at 2.7 per 1000 persons younger than 18 years of age.2 The median age at presentation is 2 years.3,4 The injury is unique to infants and young children because the radial head is less bulbous than it is in older persons and may easily become displaced. Reduction of a pulled elbow is a safe procedure that can be performed in the outpatient setting.AnatomyThe annular ligament encircles the neck of the radius and holds it tightly in place against the ulna (Fig. 1), thereby maintaining the position of the proximal radius in relation to the ulna and the capitellum of the distal humerus while allowing 180-degree rotation. When there is forceful longitudinal traction, such as when a child is pulled or lifted by the arm, the radial head is pulled underneath the annular ligament. The ligament then becomes entrapped proximal to the radial head at the level of the radiocapitellar joint (Fig. 2).IndicationsFirst, make sure that the childs history and findings on physical examination are consistent with the diagnosis. The childs history may include a witnessed event of forceful traction; however, other mechanisms of injury have also been described.4 Physicalexaminationshouldrevealpseudoparalysis,withthechildvoluntarily keeping the limb still to minimize discomfort. There will also be pain with move-ment, most often related to supination and pronation rather than to flexion and extension. In most cases there will be tenderness to palpation on the lateral side of the elbow; however, absence of this tenderness does not rule out the diagnosis. An Figure 1. The Annular Ligament.The neck of the radius is encircled by the annular ligament, which holds the radius tightly in place against the ulna.Figure 2. Entrapment of the Annular Ligament.With forceful longitudinal traction, the radial head is pulled underneath the annular ligament, entrapping the ligament.Watch the video now.The following text summarizes information provided in the video.An internet connection is required to view this video.Back to Table of Contents15NEJM Videos in Clinical Medicine: viewers choice nejm.org e32(2)affected child holds the elbow in a slightly flexed position, with the hand pronated. Further examination should also reveal a normal-looking elbow without effusion, bruising, or obvious deformity. Radiographs are almost always normal in cases of pulled elbow, so radiography should be reserved for cases in which the diagnosis is not clear. However, positioning the elbow in preparation for radiography is often therapeutic in reducing the displacement.ContraindicationsThecontraindicationstoperformingareductionarefewandareusuallyeasily recognized. If a child has a history and physical examination that are consistent with fracture, such as deformity, swelling, or bruising of the elbow or a history of a fall onto the arm from a substantial height, then a radiograph should be obtained to evaluate for fracture. If the radiograph does not reveal fracture or effusion, then reduction may be considered. However, if any other abnormalities are present, such as evidence of infection, reduction should not be attempted and immediate evalua-tion of the cause and appropriate treatment should be initiated.PreparationNo equipment is required for the reduction of a pulled elbow. The clinicians hands should be washed thoroughly as part of standard precautions.ProcedureTo prepare the parent or caregiver, explain that some discomfort may be associated with the procedure. The child may cry or scream for several minutes after the ra-dial head has been relocated to its proper position.Two techniques can be used to correct a pulled elbow. The supination technique has typically been used for reduction of pulled elbow; however, some studies com-paring the supination with the hyperpronation technique have shown that hyper-pronation is more successful.5-7 In one study, reduction was achieved on the first attempt in 95% of patients who underwent randomization to hyperpronation as compared with 77% of patients who underwent randomization to supination.6Supination TechniqueTo perform the supination technique, seat the child on the parent or caregivers lap, with the child facing you. Clasp both the hand and elbow of the affected arm (Fig. 3). Your fingers or thumb should overlie the radial head. Neither the positioning of your fingers or thumb nor the starting position of the affected arm is critical to the success of the procedure. Supinate and flex the forearm until you feel the ligament move back into position (Fig. 4). You may feel or hear a click as the ligament is re-duced. If the reduction is successful, the child should be pain free and able to move the arm normally in 5 to 30 minutes, including being able to reach for an object above the head.Hyperpronation TechniqueHyperpronation can be the primary method used to reduce a pulled elbow, or it can be used if the supination technique has failed. Seat the child on the parents or caregivers lap, with the child facing you. Clasp the hand of the affected arm as you would in a handshake (Fig. 5). Use your free hand to support the patients elbow. Hyperpronate the patients wrist (Fig. 6). You may feel or hear a click as the liga-ment is reduced. If the reduction is successful, the child should be pain free and able to move the arm normally in 5 to 30 minutes, including being able to lift the affected arm above the head.The new england journal of medicinen engl j med 371;21nejm.orgnovember 20, 2014Figure 4. Flexion and Supination of the Hand and Arm in the Supination Technique.Figure 5. Clasping of the Patients Hand in the Hyperpronation Technique.Figure 6. Hyperpronation of the Patients Wrist during Reduction of a Pulled Elbow.Figure 3. Positioning for the Supina-tion Technique.Back to Table of Contents16NEJM Videos in Clinical Medicine: viewers choice nejm.org e32(3)TroubleshootingMost reductions of a pulled elbow will be successful after a single attempt. If an initial attempt fails, the procedure may be repeated or the alternate technique may be used. If the elbow has not been reduced after three or four attempts, reexamine the arm carefully from shoulder to fingertips and obtain a radiograph to rule out fracture. However, when the cause of the injury or displacement is a fall, when the circumstances of the injury are unclear, or when it is difficult to perform a thor-ough examination because the child is uncooperative, it is prudent to obtain a ra-diograph before the third or fourth attempt at reduction. After obtaining a radio-graph, splint the elbow at an angle of approximately 90 degrees (even if the child presents with the arm more fully extended) and refer the child to an orthopedic surgeon. In the majority of such cases, the affected elbow will reduce spontane-ously during the period of immobilization.AftercareWhen a pulled elbow has been successfully reduced, aftercare is minimal. Children may resume normal activity as soon as they wish. However, parents and caregivers should be advised that the condition may recur, and the clinician should explain how the risk of recurrent subluxation can be minimized. For example, advise care-givers to avoid pulling on the arms and lifting or swinging the child by the arms. Clinicians may also consider providing family members with instructions on how to reduce a pulled elbow at home, particularly if this is not the first time the child has had pulled elbow.8SummaryPulled elbow is a common injury in young children. Reduction of a pulled elbow is a simple and benign intervention that can be performed in an outpatient setting with rapid results. Some studies have shown that the hyperpronation method is moreeffectivethansupinationandmaybelesspainful.5,6Cliniciansshouldbe competent in treating this common pediatric injury.reductionofpulledelbown engl j med 371;21nejm.orgnovember 20, 2014References1.PotisT,MerrillH.Ispronationless painfulandmoreeffectivethansupina-tion for reduction of a radial head sublux-ation? Ann Emerg Med 2013;61:291-2.2.Brown D. Emergency department vis-itsfornursemaidselbowintheUnited States, 2005-2006. Orthop Nurs 2009;28: 161-2.3.Illingworth CM. Pulled elbow: a study of 100 patients. Br Med J 1975;2:672-4.4.RudloeTF,SchutzmanS,LeeLK, Kimia AA. No longer a nursemaids el-bow: mechanisms, caregivers, and preven-tion. Pediatr Emerg Care 2012;28:771-4.5.Krul M, van der Wouden JC, van Suij-lekom-Smit LWA, Koes BW. Manipulative interventionsforreducingpulledelbow inyoungchildren.CochraneDatabase Syst Rev 2012;1:CD007759.6.MaciasCG,BothnerJ,WiebeR. Acomparisonofsupination/f lexionto hyperpronation in the reduction of radial headsubluxations.Pediatrics1998;102: e10.7.McDonald J, Whitelaw C, Goldsmith LJ.Radialheadsubluxation:comparing twomethodsofreduction.AcadEmerg Med 1999;6:715-8.8.Kaplan RE, Lillis KA. Recurrent nurse-maids elbow (annular ligament displace-ment) treatment via telephone. Pediatrics 2002;110:171-4.Copyright 2014 Massachusetts Medical Society.