CHAPTER 18 Ultrasound Guidance for Common Procedures · Ultrasound Guidance for Common Procedures...

Ultrasound Guidance for Common Procedures

CHAPTER 18

Christian H. Butcher, MD, FCCP and Sameh Aziz, MD, FCCP, FACP

INTRODUCTION

The advent of high-quality, portable equipment hasenabled the dissemination of ultrasound technologyto the bedside physician. Led by a few pioneers, thedevelopment and application of diagnostic ultrasoundare occurring in a variety of settings, including bed-side medical-surgical care, ambulatory clinics, andmedical education. In addition to its role in clinicalmedicine, ultrasound is quickly becoming recognizedas an excellent tool to teach anatomy and physiologyto students of medicine, and in several institutionsultrasound is seamlessly integrated into the medicalcurriculum (see Chapter 20).1,2

The safe performance of procedures is an impor-tant part of both medical education and medical prac-tice. In recent years, ultrasound has improved thesafety of key procedures including central venouscatheter placement and thoracentesis.3–5 This chapterwill serve as a guide to the proper use of ultrasoundfor the performance of five common procedures, ahow-to manual that can be taken to the bedside,opened to the relevant section, and placed in a con-venient location to allow for frequent consultation dur-ing the procedure. Each procedure includes ananatomic review, a review of the pertinent physicalexamination findings, correlation with ultrasound find-ings, and the most common problems encountered.Reminiscent of anatomy texts taken into the grossanatomy laboratory, this book is meant to get dirty.

VENOUS CANNULATION

IntroductionCentral venous catheterization is commonly per-formed, with an estimated 5 million central venouscatheters (CVCs) placed annually in the United States.6

In addition, peripherally inserted central catheters(PICCs) and peripherally inserted catheters sited in amidline position (midlines) have gained increased pop-ularity as an alternative to CVCs in the care of selected

patients because of their ease of insertion, longevity,and low rate of early complications.

Although venous cannulation is associated with arelatively low rate of serious complications,6 complica-tions do occur. However, an improved understandingof the cause of complications may help the providerreduce their occurrence. Interestingly, ultrasound hasbeen used to guide vascular access and as a researchtool to study the cause of certain complications ofvenous cannulation, such as the incidence of signifi-cant anatomic variation and the likelihood of punctur-ing the posterior venous wall.

Complications associated with vascular access pro-cedures are well described6 and can be categorized aspatient or operator dependent (Table 18.1). Patient-dependent factors include body habitus, coagulopathy,and anatomic variation. Operator-dependent factorsinclude the operator’s level of experience, time allottedto perform the procedure, and human factors such asfatigue and lack of ultrasound guidance.7–9 The mostcommon complications of CVC placement include acci-dental arterial puncture, failed placement, malpositionof the catheter tip, hematoma, pneumothorax, andhemothorax, the frequency of which varies dependingon the site of catheter insertion. PICC and midlineplacement are also associated with hematomas, andthese catheters are sometimes inserted into an artery.The most common complication of PICC line placementis malposition of the catheter tip into the ipsilateralinternal jugular vein or coiling in the subclavian vein ora thoracic branch such as the thoracodorsal vein.

Complications of venous cannulation are notmerely inconvenient; there are tangible repercussions,including increased costs derived from prolonged hos-pital and intensive care unit lengths of stay and addi-tional procedures, such as chest tube insertion orhematoma evacuation, to treat the complications. Forexample, a single episode of iatrogenic pneumothoraxhas an attributable length of stay of 3 to 4 days.10

Indirect costs such as additional provider time andpatient suffering are also important issues to consider.

18-Levitov_CH18_p230-246.qxd 3/31/10 4:24 PM Page 230

Ultrasound Guidance for Common Procedures 231

The rationale for ultrasound use to guide vascularaccess is robust. Legler and Nugent published abrief report describing the use of Doppler ultrasonog-raphy to locate the internal jugular vein for cannula-tion back in 1984.11 Since then, two meta-analysesinvestigating the use of ultrasound for CVC place-ment,12,13 several review articles, standardized proce-dure guidelines,14,15 and results from the SonographyOutcomes Assessment Program (SOAP-3) trial havebeen published.16 These and other studies clearlydemonstrate that the use of two-dimensional (2D)ultrasound during central venous access is associatedwith fewer complications, fewer attempts before suc-cessful cannulation, shorter procedure times, andfewer failed procedures when compared to a land-mark-based approach. As a result, the Agency forHealthcare Research and Quality and the BritishNational Institute of Clinical Excellence (NICE) haveissued statements advocating the use of ultrasoundguidance in central venous access procedures.17,18

A 2007 study by Wigmore et al confirms that imple-mentation of the NICE guidelines has resulted in fewercomplications.19

Some providers continue to resist the adoption ofthe ultrasound-guided technique and use ultrasoundonly in potentially “difficult to cannulate” patientssuch as the morbidly obese or when landmark-basedcannulation has failed.20 Unfortunately, it is difficult topredict which patients will be hard to cannulate, andthe recognition of a failed attempt, as may arise froman occluded vessel, can be viewed only retrospec-tively after the failure has occurred and the patienthas been adversely affected.21 Therefore, the consider-ation of ultrasound up front to improve safety in allcentral venous access procedures is recommended.And, as evidenced by Lee et al, the technique is easilytaught.22

Review of Ultrasound

Transducer SelectionUltrasound transducers come in a variety of frequen-cies, each with different properties and clinical applica-tions. Recall that the relationship between ultrasoundfrequency and the depth of tissue penetration is aninverse relationship. Thus, low-frequency ultrasound(1–3 MHz) penetrates more deeply than high-frequencyultrasound (7–10 MHz). The relationship between fre-quency and image detail, or resolution, is proportional.This means that low-frequency ultrasound has poorerresolution than high-frequency ultrasound. Therefore,high-frequency ultrasound provides a very detailedimage of superficial structures, to a depth of approxi-mately 5 cm, but cannot penetrate into deeper tissues.Alternatively, lower-frequency ultrasound is capable ofreaching into deeper structures but provides a less-detailed image. These relationships form the basis fortransducer selection. For percutaneous vascular access,which is a procedure that is superficial, higher-frequencytransducers are ideal.

ModesA-mode ultrasound has very few clinical applicationsand is not discussed further here. B-mode ultrasounduses an ultrasound probe with many active elementsaligned in a specific orientation, or “array,” to create arecognizable 2D image (Fig. 18.1, top). B mode is themost common mode currently employed in diagnosticmedical ultrasound. M-mode ultrasound uses informa-tion obtained with B mode to create an image thatdemonstrates the movement of structures over time

TABLE 18.1. Causes of Complications inVascular Access: Patient Versus OperatorFactors

Patient Dependent Operator DependentBody habitus ExperienceCoagulopathy Time allotted for procedureVascular anatomic Fatiguevariation

Prior surgery with Lack of ultrasound usedistortion of anatomy

Figure 18.1. Typical B-mode (two-dimensional)image (top) and M-mode image (bottom) of the inter-nal jugular vein.

18-Levitov_CH18_p230-246.qxd 3/31/10 4:24 PM 31

232 Bedside Ultrasonography in Clinical Medicine

(Fig. 18.1, bottom). The most common application ofM mode is to assess valve leaflet movement and wallmotion in cardiac ultrasound.

Doppler mode also has several forms. The simplestproduces no image; there is only an audible signal thatvaries in intensity with the velocity of the structurebeing studied (e.g., blood). Color Doppler takes velocityinformation obtained by the Doppler shift and assignscolor to it. Most modern ultrasound equipment usesDoppler or color Doppler in combination with B modeto both create an image and simultaneously superim-pose information about blood flow velocity (Fig. 18.2[see also color insert]). Color Doppler is very com-monly used in vascular applications, such as vascularaccess. An important concept to understand is thatthe strength of the Doppler signal is related to thevelocity of the target tissue (e.g., blood) and the angleof incidence, with the best estimate of velocity occur-ring at an angle approaching zero. If the same vessel isimaged in a plane 90° from the direction of blood flow,there is no perceived motion of blood either toward oraway from the transducer, and the Doppler signalfades. Also, when the angle of incidence changes fromone “side” of the 90° mark to the other side, the colorof the blood within the target vessel changes (e.g.,from red to blue) (Fig. 18.3). This is very importantand a potential source of error when a beginner isbecoming familiar with orientation and selecting avessel for cannulation.

Techniques of Ultrasound GuidanceUltrasound is not a substitute for a thorough knowl-edge of the landmark-based technique for central

venous cannulation. Frequently, the beginner mayfocus on the image on the screen and be inattentive toanatomic landmarks and the position of the needle. Infact, ultrasound should be used as an educational toolto teach and confirm the landmark-based techniquewhenever possible. Just as computed tomography ofthe chest is an excellent tool to teach interpretation ofthe chest x-ray in a retrospective fashion, ultrasoundis an excellent tool to teach landmark-based cannula-tion (including its limitations).

Ultrasound guidance can be categorized as static ordynamic. Dynamic guidance refers to performing theprocedure in real time with ultrasound imaging view-ing the needle puncturing the vessel wall. Static guid-ance refers to identifying the target vessel, assessingpatency, and marking an appropriate insertion sitewith ultrasound, then cannulating blindly. For vascu-lar access, static guidance appears to be inferior todynamic but still better than the landmark-basedtechnique alone.16 Table 18.2 provides a comparisonbetween static and dynamic guidance techniques.Dynamic guidance is more technically demandingsince it requires significant eye-hand coordination.

Anatomic Review and PhysicalExamination Correlation with Ultrasound Anatomy and Physiology

Planes For our purposes, there are two planes to be consid-ered: transverse and longitudinal, which refer to theorientation of the ultrasound transducer and the imageto the vessel axis. A transverse view is a cross sectionalview and provides the operator with information

Figure 18.2. Color flow Doppler image of the internaljugular vein (top) and carotid artery (bottom). (Seecolor insert.)

Tips: Color Doppler

A B C

Figure 18.3. The effect of varying the angle of inci-dence on color flow Doppler. Intensity and/or colorwill change depending on angle of incidence. Blood isflowing away from probe A, but if you change theangle (such as in probe C), the blood will flow towardthe probe, which changes the color.


about structures that lay adjacent to the vessel of inter-est. For example, a cross-sectional view of the internaljugular vein will enable visualization of the adjacentcommon carotid artery and, perhaps, the vagus nerve,thyroid gland, and trachea.

A longitudinal view will depict structures anteriorand posterior to the vessel of interest and may allowfor visualization of the entire needle during cannula-tion but does not allow simultaneous visualization ofstructures lateral to the vessel. All commonly utilizedcentral veins can be visualized in either orientation.As a general rule, transverse views tend to be easierfor the novice to learn ultrasound-guided cannulation,but complications such as puncturing the posteriorvessel wall may be reduced by using the longitudinalview as reported by Blaivas et al23 and commented onby Levitov et al.24

Recently, a study was published touting the use of ahybrid method of obliquely imaging the target vessel,the implication being that this approach may confer thebenefits of both a transverse and longitudinal view.25

Methods of OrientationOrientation is probably the most important step to asuccessful procedure. Problems with orientation canlargely be prevented by ensuring proper patient,transducer, and ultrasound machine position. Mosttransducers have an identifiable mark, known as anotch, on one side. This corresponds to a mark dis-played on one side of the image and allows right/left,or lateral, orientation (Fig. 18.4). Where orientation isuncertain during a procedure, a finger can be rubbedon one side of the transducer surface to produce animage and confirm the orientation. In general, thescreen should be in the operator’s line of sight duringvessel cannulation; in practical terms, the needleshould point directly at the screen during cannulation.For a subclavian line, the machine is placed on theopposite side of the patient; the machine is placed on

the ipsilateral side for an internal jugular line (Fig. 18.5).For femoral insertion, the screen can be placed oneither the ipsilateral side or the contralateral side atthe level of the patient’s chest.

Differentiating an Artery from a VeinUpon reviewing the vascular anatomy of the neck,recall that the common carotid and internal jugularveins travel together in the carotid sheath (along withthe vagus nerve). Despite what many readers learnedin anatomy, there is significant variation in the posi-tion of the vein relative to the artery. In fact, the veinis either posterior to, directly anterior to, or medial tothe vein in a significant minority of patients.15 Itbecomes important, therefore, to be able to differenti-ate artery from vein by some other means. Arteries, ingeneral, are smaller and thicker walled than accompa-nying veins on ultrasound. In addition, veins are usually

Figure 18.4. Orienting the transducer to the image.The notch on the transducer corresponds to the indicator on the screen.

TABLE 18.2. Comparison of Static Versus Dynamic Guidance*

Dynamic Guidance Static GuidanceUltrasonic localization and image-guided cannulation Ultrasonic localization and marking of landmarks onlyMore precise and “real time” Cannulation is not image guidedMore difficult to maintain sterility Time delay between marking and cannulationRequires significant hand-eye coordination Less difficult to maintain sterility

Less technically demanding

*In general, the advantages and disadvantages apply to all ultrasound-guided procedures.




very easily collapsed with the application of pressurevia the transducer. The character of vessel pulsationis another clue; arteries will pulsate with the cardiaccycle, and veins may pulsate with the respiratory cycle(respiratory variation in venous diameter), unless sig-nificant right-sided heart failure is present. A fourthmethod is to apply color Doppler to the vessel andobserve the character of the color pulsation. The cor-rect use of color flow Doppler requires that the opera-tor know how the machine is set up and at what anglethe vessel was “Dopplered.” The machine can be setso that blood moving toward the transducer is eitherred or blue. However, if the angle of insonation of thevessel crosses a line perpendicular to the vessel, thecolor will change (see Fig. 18.3). It is useful to comparecolor Doppler signals of all vessels in the area of inter-est, paying close attention to the angle of the incidentultrasound beam; with a little practice arterial flow iseasily differentiated from venous flow. Remember thatlarge, rapid fluctuations in intrathoracic pressure cancreate very high venous blood flow velocities that canmimic arterial flow; this situation may require the useof other methods such as respiratory variation orcompressibility to help differentiate the vessel type.

Occasionally, the vein cannot be visualized. Themost common reason for this is hypovolemia withassociated venous collapse, which can be remediedby placing the patient in the Trendelenburg positionor applying a vagal maneuver or fluid administration.Other less common causes are agenesis, chronicocclusion or scarring of the vessel, and clot that iscompletely occluding the lumen. Clot may be difficult

to distinguish from the surrounding tissue (Fig. 18.6).In this case, a thorough examination of the proximaland distal parts of the vessel should be performed, anda formal venous Doppler procedure should be per-formed to evaluate for deep venous thrombosis priorto any attempted central venous cannulation. If accessis critical, and vessel presence or patency cannot beassured, a different vessel should be cannulated.

Technique

Internal Jugular Vein1. The patient is positioned appropriately. The head

should be rotated slightly contralaterally, with theneck extended. Severe rotation of the neck andhead should be avoided, since this may lead to sig-nificant distortion of the anatomy and mayincrease the amount of overlap of the carotidartery and jugular vein. The bed should be placedin Trendelenburg position, and the ultrasoundmachine should be placed by the ipsilateral side ofthe bed, at about the level of the patient’s waist.

2. An initial examination of the landmarks withoutultrasound should be performed, including selec-tion of an insertion site. The site should then be

Figure 18.6. A thrombus (arrow), especially ifchronic, can be difficult to distinguish from surround-ing tissue. This is a clot in the internal jugular vein.This vessel would be impossible to compress fully,and color flow would be absent. Prior to cannulation,the entire vessel should be scanned since clot maybe distal to the proposed insertion site. Both sidesshould be scanned, especially when placing an inter-nal jugular line; a central line placed in a patient witha contralateral internal jugular clot greatly increasesthe risk of bilateral thrombus.

Figure 18.5. Comfort should be maximized by posi-tioning the machine “ergonomically”; in general, theneedle should be pointing toward the ultrasoundimage during cannulation.


confirmed with ultrasound. This technique pro-vides the operator with immediate feedbackregarding landmark-based site selection and there-fore facilitates teaching both the landmark-basedapproach and the ultrasound-guided approach.During this process, the vein should be identifiedand assessed for patency.

3. The patient’s skin can now be prepped in sterilefashion and full barrier precautions used to main-tain sterility and reduce the incidence of catheter-related infections.26 Ultrasound use introducesanother piece of equipment onto the sterile field,making the maintenance of sterility more difficult.While learning, one needs to pay special attentionto this issue in order to develop good habits. Asterile ultrasound sheath should be placed on thesterile field for when an assistant hands the oper-ator the ultrasound transducer.

4. After the patient is prepped and draped, thecatheter is set up per normal routine. All portsshould be flushed with bacteriostatic saline toremove air and to test for occlusion caused bymanufacturing defects. The components neededfor catheter insertion, including needles, wire,dilator, scalpel, catheter, and sterile transducercover, should be arranged in an orderly fashionand within easy reach.

5. The operator acquires the transducer, places it inthe sterile cover, and secures it on the sterile field.The transducer can either be “picked up” by theoperator whose gloved and sterile hand is insidethe transducer cover like a puppet or, alternatively,an assistant can insert the transducer in the openend of the cover. The end sheath is then extendedto cover the transducer cord, and sterile rubberbands are applied to secure the sheath in place.

6. A second ultrasound examination should be per-formed to ensure that the original insertion site isstill viable. Remember that proper orientationevery time the probe is applied to the patient isessential for ensuring an appropriate procedure.

7. When cannulating the vessel, the operator usesthe same insertion site and needle trajectory as heor she would when using the landmark-basedapproach (lateral, medial, etc.). If using the trans-verse plane for ultrasound guidance, which isespecially good for novices, the operator must besure to center the vessel lumen on the screen;remember that if the vessel is centered on thescreen, it is directly underneath the middle of thetransducer head.

8. Sometimes it is useful to perform a “mock poke” toconfirm the proposed insertion site relative to theunderlying vessel. This is done by laying the nee-dle on the skin surface, then applying the trans-ducer to it. The acoustic shadow produced by theneedle should be directly over, or superimposedon, the target vessel (Fig. 18.7). The skin punctureshould be approximately 1 cm proximal to thetransducer, which in most cases will result in visu-alization of the needle tip entering the vessel with-out having to move the probe much. If the needletip cannot be visualized indenting either the sub-cutaneous tissue overlying the vessel or the vesselitself, the operator moves the probe along the axisof the vessel while slightly “agitating” the needle;this will accentuate the image of the needle andtip. The point of the “V” caused by indenting thesubcutaneous tissue above the vein with the nee-dle tip should be directly over the vessel. Theoperator should be sure to visualize the tip of theneedle at all times (it is very easy to misinterpretthe shaft of the needle as the tip) and to movethe probe axially along the vessel frequently to

Figure 18.7. Mock poke technique. This shows atransverse view through the internal jugular vein.Note the acoustic shadow of the overlying needle.




maintain imaging of the tip. If done properly, theneedle tip should be seen entering the lumen atabout the same time as the flash of blood is obtainedin the syringe.

9. Once the vessel has been successfully cannulated,the operator sets aside the transducer and pro-ceeds with wire placement. Intravascular positionof the wire can be confirmed with ultrasound,which can then be saved for documentation in themedical record.

10. Once the line is in place, flushed, secured, anddressed, a quick ultrasound examination of theanterior chest wall can be performed to evaluatefor a pneumothorax (see Chapter 7). Pleural ultra-sound specifically looking for an absence of nor-mal “sliding pleura” is highly sensitive for identify-ing pneumothorax.27

11. The use of ultrasound should be documented inthe medical record. Typically, a statement regard-ing the use of ultrasound to assess the locationand patency of the vessel and an image of the wireor catheter in the vessel lumen is sufficient fordocumentation and often provides sufficient docu-mentation for reimbursement. Additionally, astatement about the presence or absence of slid-ing pleura should be included.

Subclavian VeinTypically, the subclavian vein is slightly more difficultto visualize ultrasonographically than either the inter-nal jugular, axillary, or femoral veins. This is becauseof its position under the clavicle, which requires sig-nificant angulation and manipulation of the trans-ducer to acquire a useful image. Two additional chal-lenges are the difficulty visualizing the vein in obesepatients using an infraclavicular view and the inabilityto adequately compress the vein to exclude the pres-ence of clot.

In our experience, it is usually easier to visualizethe subclavian with a longitudinal supraclavicularview in obese patients since an adequate transverseview or infraclavicular longitudinal view is often tech-nically challenging. Considering the ease with whichthe internal jugular and axillary veins are visualized,we have largely abandoned the subclavian vein in ourpractice, except for specific clinical situations, such asfor long-term total parenteral nutrition administrationor for emergency central venous access.

Axillary VeinUsing the axillary vein for central venous access hasmany unique advantages over using other sites.28–31

Although not well-studied, since the insertion site ison the anterior chest, axillary catheterization likelyshares a low incidence of catheter-related infectionswith the subclavian approach. Unlike the subclavianvein, using the axillary vein may be associated withfewer complications, such as pneumothorax, hemoth-orax, and chylothorax. The axillary vein is usually eas-ier to compress than the subclavian vein and allowsan easier recognition of clots. There is, however, theadditional potential complication of causing a brachialplexus injury, particularly if a far lateral approach isused.30 One distinct disadvantage of the axillaryapproach is the unique dependence on ultrasound toensure localization and subsequent cannulation; land-mark techniques are not as effective as with the othercommon sites used to access the central venous sys-tem. Figure 18.8 shows proper transducer placementfor viewing the axillary vein transversely. As withinternal jugular and subclavian access approaches, aquick postprocedure scan of the chest should be per-formed to ensure sliding pleura, which essentiallyeliminates the possibility of pneumothorax.27

Femoral VeinFemoral cannulation remains a popular approachbecause of its relatively low incidence of life-threateningcomplications. However, several clinically impor-tant complications may occur that lead to signifi-cant morbidity. Accidental (or intentional for thatmatter) femoral arterial cannulation, especially incoagulopathic patients, may cause life-threateningretroperitoneal hemorrhage and hematoma. Inadvertentstimulation of the femoral nerve with the cannulationneedle can cause intense pain. A puncture site that is

Figure 18.8. Transducer position to image the axillary vein.


too proximal can also result in inadvertent punctureof intraperitoneal structures. Ultrasound can helpavoid some of these important complications.

Like internal jugular, subclavian, and axillary cannu-lation, the first step in successful femoral access isachieving proper orientation. The ultrasound machineshould be placed in a location that encourages opera-tor comfort. The entire area should be scanned, withidentification of all vascular structures, including thefemoral artery, common femoral vein, and saphenousor profunda femoris vessels if possible. Once the veinis identified, it should be evaluated for the presence ofclot. Additionally, a longitudinal view of the veinshould be obtained as it dives under the inguinal liga-ment, and the ligament itself should be marked on theskin. If a femoral hernia is not present, this stepensures that an intraperitoneal puncture will notoccur (Fig. 18.9). All other steps are identical to thoselisted earlier for the internal jugular vein.

Common Pitfalls

The most common pitfalls encountered in ultrasound-guided vascular access are easily avoided. Theseinclude not understanding the relationship betweentransducer frequency and both depth of penetrationand image resolution, incomplete understanding ofthe basics of color Doppler and how the angle of theincident ultrasound beam can alter the Doppler signal(and color), poor technique in terms of always keep-ing the needle tip in view during image-guided cannu-lation, not paying attention to equipment setup tomaximize comfort and ergonomics during the proce-dure, and not scanning the entire vessel to exclude thepresence of thrombus. These pitfalls can be avoidedby proper training and subsequent practice.

LUMBAR PUNCTURE

IntroductionLumbar puncture, first described by HeinrichQuincke, has been performed for over a century.Typically, the procedure is performed after properpositioning of the patient and careful palpation ofanatomic landmarks to help locate an appropriate sitefor needle insertion. However, successful lumbarpuncture can be difficult to achieve in certain patientpopulations (e.g., the morbidly obese), presumablybecause of obscuration of palpable anatomic land-marks such as the spinous processes. In recent years,there has been a renewed interest in augmenting thelandmark-based technique with ultrasound.

The first reported use of ultrasound to help guidelumbar puncture was published in 1971 in the Russianliterature.32 Since that time, the technique remainedrelatively dormant until the last decade, when it wasresurrected by anesthesiologists for use in guidingspinal and epidural blocks.33–37 In fact, most of the datacurrently available have been reported in the anesthe-sia literature; incorporation of ultrasound guidanceinto critical care and generalist practice has been amore recent development. The main advantages ofadding ultrasound guidance to the landmark-basedtechnique are shown in Table 18.3.


Normal lumbar spinal anatomy is shown in Figure 18.10.As can be seen, the needle used for lumbar puncturemust traverse the skin, subcutaneous tissues, and

Figure 18.9. Longitudinal view of the femoral vein asit “dives” under the inguinal ligament. The inguinalligament is the confluence of bright lines in the leftupper quadrant of the image.




supraspinous ligament; then it must navigate throughthe spinous processes and the interspinous ligamentbefore traversing the ligamentum flavum before itenters the dural space and, finally, the subarachnoidspace. Success is inherently dependent on proper nee-dle position and angulation. Since the conusmedullaris rarely extends beyond L3 in most studies,the most common site of insertion is the L3-L4 inter-space. Figure 18.11 shows a transverse view throughthe lumbar spine at the level of L4. Note the easily dis-tinguishable tip of the spinous process as well as thetransverse processes. This transverse view facilitatesidentification of the midline, which can be surprisinglydifficult to identify by palpation in some patients.Figure 18.12 shows a longitudinal view of the L3-L4level. Note the appearance of the spinous processesas well as the presence of the ligamentum flavum,

which overlies the dura. In one study, the depth of thedural reflection correlated very well with needle depthduring insertion.38

Technique

A linear array transducer works well for most patients.In our institution, we use the same 6- to 13-MHz lineararray transducer used for vascular access procedures.Alternatively, a curvilinear 5-MHz transducer could besubstituted. The patient is positioned appropriately,either sitting upright, leaning forward, or on the sidein the lateral recumbent position (particularly if pres-sure measurements will be obtained). Puncture can beguided either statically or dynamically. In static guid-ance, an appropriate site is marked on the skin by firstfinding the L3-L4 level by the usual technique (palpa-tion of the iliac crest), then marking the exact midlinewith a transverse ultrasound view, followed by locat-ing and marking the appropriate interspace with a lon-gitudinal view. Once the two marks are made, theinsertion site will be the center of the “+”; it helps tomake a skin indentation with a sterile instrument incase the “+” is removed during sterile preparation of

TABLE 18.3. Advantages of Using UltrasoundGuidance for Lumbar Puncture

Allows visualization of the interspace and the exactmidline as well as the target (ligamentum flavum)

Allows one to easily see the required needle trajectory between the spinous processes

Allows one to gauge the required needle depth priorto needle insertion

Reduces failure rateReduces procedure time

Figure 18.10. Normal spinal anatomy.

Figure 18.11. Transverse ultrasound view throughthe spine, clearly showing the tips of the spinousprocesses as well as the transverse processes.


the skin (see Fig 18.13). If dynamic guidance isemployed, all the above steps are done, followed byneedle insertion under ultrasound guidance; the nee-dle tip can be seen to enter the area of the dural sac.As mentioned earlier, one can measure the distancefrom the skin to the dural reflection on the image; thishas been found to correspond well to the requireddepth of the needle to obtain fluid. Once learned, thistechnique can improve success rates up to 92% asreported in one series.38

Common Pitfalls

This technique is relatively resistant to error.However, heavy ligamentous calcification can obscureunderlying anatomy, so particular care is needed inthese patients. Fortunately, calcification rarelyimpairs the operator’s ability to identify the midline oran appropriate interspace for needle insertion.Another very common pitfall, much more difficult toovercome, is the presence of posterior spinal hard-ware. There are more advanced techniques to obtain

spinal fluid in these patients, but this is beyond thescope of this book.

THORACENTESIS

IntroductionUltrasound-guided thoracentesis is a very usefulprocedure, especially in the critical care settingwhen visualization of pleural effusions in supinemechanically ventilated patients becomes difficult. Infact, ultrasound-guided thoracentesis was found tobe a safe procedure with a lower risk of pneumotho-rax in comparison to blind thoracentesis in bothmechanically ventilated and nonventilated patients.4,39

Furthermore, it has been found to be a helpful adjunctwhen used to evaluate unsuccessful thoracentesis.40

Evaluation of the pleural space and pleural fluidwith ultrasound is useful to help determine the natureof the effusion and help differentiate between tran-sudative and exudative effusions. A transudative pleu-ral effusion is usually anechoic, while an exudativeeffusion may have complex septation, echogenic mate-rial, or the presence of pleural thickening41 (Figs. 18.14and 18.15).

In addition to providing useful information aboutthe type of fluid present, ultrasound can help with the

Figure 18.12. Longitudinal view through the lumbarspine. The spinous processes can be seen, as can theligamentum flavum at the “floor” between the twovertebrae. The distance between the skin and the ligamentum flavum approximates the needle lengthrequired to enter the space and reach fluid.

Figure 18.13. A combination of transverse and longi-tudinal views to mark the midline and appropriateinterspace, respectively.




quantitative evaluation of the pleural fluid.42 In mostcircumstances, this is not essential information, and,therefore, we will not discuss techniques to quantifypleural fluid any further.


The pleural space can be thought of as being roughlyconical in shape, bordered by the chest wall anteriorly,laterally, and posteriorly; the mediastinum medially;and the diaphragm inferiorly. From a sonographic view-point, only the anterior, lateral, and posterior bordersare accessible. Fluid, if it is free flowing, accumulatesdependently, inferiorly and posteriorly in the uprightchest and posterolaterally when the patient is supine.When fluid is present in the thorax, it is always borderedby three structures: the chest wall, the diaphragm, andthe lung. Knowledge regarding the location and appear-ance of intra-abdominal structures, such as the spleen,liver, and kidneys, is absolutely necessary to be able toperform ultrasound-guided thoracentesis safely. Theliver is shown in Figures 18.16A and 18.16B as a relativelyhomogenous structure bordered superiorly by thediaphragm and inferiorly by the kidneys. The kidneys areusually very easy to recognize, having an outer cortexand inner medulla. The potential space in between theliver and the right kidney (hepatorenal recess), as well asthat between the spleen and the left kidney (splenorenalrecess), can occasionally be confused with the pleuralspace (Figure 18.17), especially when large amounts ofintra-abdominal fluid are present (Figure 18.18).

X

Figure 18.14. Anechoic appearance indicates an uncom-plicated transudative pleural effusion. X marks the spot.

Figure 18.15. Complicated parapneumonic effusionwith septation (arrow).

A B

Figure 18.16. Appearance of the liver, spleen, and kidneys in relation to the diaphragm.(A) The different appearance of the liver from the chest ultrasound window may be con-fused with a pleural effusion. (B) Normal appearance of the liver and kidney from thechest ultrasound window.


Pleural fluid usually appears homogenously black ifthe effusion is simple. Complex effusions may appear“speckled” or otherwise inhomogeneous. Occasionally,a spider-web appearance will be encountered, whichindicates loculation. Dynamic characters are almostuniversally present, which include a moving diaphragm,moving lung, and movement within the effusion itself.

Technique

1. The patient is positioned appropriately. The bestposition for thoracentesis is with the patient sit-ting upright with arms elevated and extended infront, especially for nonloculated effusions.However, when ultrasound is utilized, thoracente-sis becomes feasible even in the lateral and supinepositions, which is helpful in assessing critically illmechanically ventilated patients because it wouldbe difficult to place them upright without signifi-cant ancillary support.43,44

2. A 3.5- to 5-MHz curvilinear ultrasound probe isused in a longitudinal orientation (perpendicularposition of the ultrasound probe in relation to theunderlying rib) to identify the location, quantity,and quality of the fluid, if present.45

3. One should scan below the effusion to identify thediaphragm, the spleen on the left side, and the liveron the right side. Pay particular attention in orderto not confuse fluid in the hepatorenal recess orthe splenorenal recess with pleural fluid.

4. The operator confirms that there is enough fluid tocreate a safe distance between the planned site of

entry and vital organs, remembering that thediaphragm is dome shaped; if one plans toadvance the needle close to it, he or she may inad-vertently penetrate through it if the needle isadvanced too far.

5. The operator confirms the presence of the pleuraleffusion by identifying at least three borders andat least two dynamic characters; usually the pleu-ral fluid is bordered by the diaphragm inferiorly,the chest wall anteriorly, and the lung posteriorly(or medially) (Fig. 18.18).

6. M mode can be used to confirm the presence ofpleural fluid using the sinusoid sign, especiallywith minimal pleural effusion (Fig. 18.19).46

Figure 18.17. Appearance of fluid in the hepatorenalrecess. This can occasionally be confused with pleural fluid (arrow).

Figure 18.18. Appearance of pleural fluid confirmedby the presence of the diaphragm (hyperechoic lineon the left) and the collapsed lung (compressionatelectasis [white arrow]).

Figure 18.19. The borders of a pleural effusion areshown: diaphragm, pleura, and collapsed lung.




7. Once the position of the effusion is identified, atransverse position of the ultrasound probe isused to evaluate both the proper puncture siteand the presence of any superficial vascular struc-tures.

8. The operator plans the needle trajectory based onthe location of fluid, the presence and distance ofany underlying structures, and the angle of inci-dence of the ultrasound transducer during theexamination. In general, once a good view isobtained with the transducer, the operator men-tally note the position and angle of the probe; thiswill be the position and angle of the needle duringinsertion.

9. The operator cleans the site of entry withChloraPrep and sterilely drapes it. One may use asterile cover for the ultrasound probe to rescan thearea again to confirm the optimum site of entry.

10. Using a 25- to 30-gauge needle, the operator infil-trates the skin with local anesthetic using 1% or2% lidocaine. Using a 22-gauge, 1.5-inch needle, theoperator infiltrates local anesthetic to the subcu-taneous tissues and intercostal space. Thecatheter is inserted through the planned tractuntil pleural fluid is obtained and is then advancedinto the pleural space while the inner needle ispulled back.

11. Once the procedure is done, the catheter is with-drawn from the pleural space.

12. Postprocedure ultrasound evaluation of the pleu-ral space is recommended. One needs to evaluatefirst for the resolution of the pleural effusion andfor the presence of any residual fluid, and sec-ondly for postprocedure complications such aspneumothorax. One study looking at the compar-ison between chest x-ray and chest ultrasoundfor postinterventional pneumothorax showedthat transthoracic ultrasound had a sensitivityand specificity of 100% to rule out postinterven-tional pneumothorax. About 16% of cases withpostprocedure pneumothorax were missed withchest x-ray.47

A freehand technique in which real-time ultrasoundguided thoracentesis is utilized (so-called dynamicguidance) is highly recommended for small pockets ofpleural fluid or in patients on mechanical ventilation.This technique requires significant hand-eye coordina-tion, however. The advantage is that needle insertionis visualized with ultrasound, so the operator can seethe needle tip as it is advanced.

Pitfalls

There really are no pitfalls unique to ultrasound-guided thoracentesis. However, all the usual pitfalls oftraditional thoracentesis exist, which include dry tap,re-expansion pulmonary edema, and pneumothorax.The most common causes for dry tap when ultra-sound guidance is used are either poor angle selectionor the presence of a complicated effusion with inter-pleural septation. Feller-Kopman et al found that re-expansion pulmonary edema occured more often ifthe patient experienced chest discomfort during theprocedure, there was rapid removal of pleural fluid, orthe end-expiratory pleural pressure was noted to beless than –20 cm H2O.48

PARACENTESIS

IntroductionParacentesis is a very commonly performed proce-dure, typically indicated as part of the initial evalua-tion of patients with new-onset ascites or patientswith a known history of ascites who develop clinicaldeterioration. Using ultrasound guidance for paracen-tesis has been shown to decrease the duration,increase the ease, and improve the accuracy of theprocedure, partly by avoiding unnecessary proce-dures in patients with minimal or no ascites.49 Otheradvantages of ultrasound use to guide paracentesisare that it can detect as little as 10 mL of free fluid witha specificity of 100%,50 help identify the character ofthe fluid, and be used to determine an appropriatepoint of entry51 (Fig. 18.20). Theoretically, ultrasound

Figure 18.20. M mode of a small effusion showingthe sinusoid sign (arrow).


guidance can help avoid puncture of vital organs,such as the liver, kidney, and spleen.


The peritoneal space is bordered by the diaphragmsuperiorly, the abdominal wall anteriorly and laterally,and the retroperitoneum posteriorly. Inferiorly, theperitoneal space is contiguous with the pelvis and isbordered by the pelvic floor. The abdomen presents afairly unique challenge in that one of its residentorgans, the bowel, is highly mobile. In addition, severalintra-abdominal organs are highly subject to changes inintrathoracic pressure and can change position duringrespiration. Another challenge is that in morbidlyobese patients, it is very difficult to appreciate the clas-sic fluid wave on physical examination maneuvers.Therefore, it is quite advantageous for medicalproviders to know basic abdominal ultrasonographicanatomy (see Chapter 10). For our purposes, rememberthat the liver is separated from the right kidney by apotential space known as the hepatorenal recess. Thisspace can fill with fluid and occasionally be mistakenfor pleural fluid, with the liver being mistaken for lung.On the left side, the spleen is likewise separated fromthe left kidney by the splenorenal recess. The kidneys,probably the most recognizable structure on ultra-sound, are located retroperitoneally and are mosteasily imaged from a posterolateral transducer position.Bowel, especially in patients with large fluid collections,can be seen as multiple free-floating loops. A particu-larly important structure to be able to recognize is theurinary bladder, which, if full, can be mistaken forascites. The bladder typically has easily identifiablewalls and may have a visible balloon if catheterized.

Technique

1. Prior to the procedure the patient is asked toempty the urinary bladder to decrease the risk ofbladder perforation. Also, any coagulopathy needsto be corrected prior to commencing.52

2. Most of the time the procedure is performed whilethe patient is supine, although it can also be donewith the patient in the sitting position.44

3. Curved array transducers are preferred for evalu-ation of the abdomen and to identify the qualityand the quantity of ascitic fluid. Ultrasound is ableto reveal as little as 100 mL of ascitic fluid53 andcan, therefore, determine a safe site of entry.

4. The left lower quadrant approach is considered tobe a safe starting point. One may use color flowDoppler to evaluate for cutaneous veins at the pro-posed site of entry and to help avoid the inferiorepigastric artery.

5. The operator performs a careful evaluation of theentire abdomen, paying particular attention to theposition of the liver, spleen, bowels, and bladder;this step is key to avoiding complications.

6. The operator selects an appropriate site for nee-dle insertion.

7. Once the site of entry is identified, the area is thencleaned and draped.

8. The transducer is sheathed in a sterile probe cover.

9. Prior to the procedure, ultrasound is used again toconfirm the location of the ascitic fluid as well asthe expected needle depth at which fluid shouldbe encountered.

10. The operator introduces the needle into the peri-toneal fluid using a “Z-line technique” to decreasethe risk of postprocedure leak.

11. Using a free-hand technique with real-time ultra-sound (dynamic guidance), the operator shouldtry to keep the needle and the ultrasound beam inthe same plane. Again, this is the key point forsuccessful thoracentesis, paracentesis, and thelongitudinal approach for central line placement(Figs. 18.21 [see also color insert] and 18.22).54,55

12. If dynamic guidance is used, the operatorshould be able to see both the needle and thecatheter entering the peritoneal space in realtime (Fig. 18.23).

13. Once fluid is obtained, the operator sets the trans-ducer aside and proceeds with fluid evacuation.

Pitfalls

As with thoracentesis, the pitfalls associated withultrasound guidance for paracentesis are the same aswith the traditional technique. Large-volume paracen-tesis (>10 liters) is usually avoided, as it may lead tosevere hypotension.52 Damage to blood vessels canoccur, with postprocedure hemorrhage that can occurfrom 6 to 48 hours after the procedure.56 However,careful evaluation of superficial veins and arterieswith ultrasound can help avoid bloody paracentesisand even inferior epigastric artery aneurysm. Ofcourse, areas of previous scars and areas of intra-abdominal adhesion should be avoided.




DOCUMENTATION, CODING, ANDREIMBURSEMENT

It is the responsibility of the physician to select theappropriate code for the services rendered. CurrentProcedural Terminology (CPT) code 76604 can be usedfor diagnostic ultrasound of the chest and code 76700 fordiagnostic ultrasound of the abdomen, while CPT code76942 can be used for ultrasound-guided thoracentesis.57

There are two separate payment components that canbe requested: the professional fee and the facilityfee. The professional fee is the physician’s fee forthe medical services provided. The facility fee is thefee charged to offset the cost of equipment and main-tenance. For most ultrasound-guided procedures, theadditional professional fee attributable to ultrasoundguidance is nominal. However, the facility fee can be

Short axis Long axis

b

A B

a, c b

a c

A B

Figure 18.21. Diagram comparing transverse and longitudinal approach, illustratingthe need for for the visualization of the needle tip (see color insert). In plane B needleappears in the center of the vessel while the tip has penetrated the posterior wall.(Adapted with permission)

Figure 18.23. The arrow demonstrates the tip of theparacentesis needle in the peritoneal cavity duringreal-time guidance for paracentesis.

Figure 18.22. Longitudinal view of the internal jugu-lar vein with the needle seen in the vessel lumen(white arrow).


quite large. One caveat is that the person or groupcharging the facility must own the equipment. If theseprocedures are going to be billed to the patient, ade-quate documentation that ultrasound was indeed usedmust be permanently stored in the medical record.Adequate documentation, for example, would include astatic photo of the vein before and after cannulation,showing the needle or guidewire in the vessel lumen.Video loops of the procedures may also be stored on acomputer for access should an audit be performed.

FUTURE DEVELOPMENTS

Ultrasound guidance has been used for many yearsand with excellent success in interventional radiology

suites. As these techniques become disseminated tononradiologist practitioners, the limits of what is“standard” change. Already, nephrologists are learningto perform ultrasound-guided renal biopsy, generalinternists are performing ultrasound-guided liverbiopsy, and critical care practitioners are aspiratingabdominal abscesses. Standardized training programswill emerge, with clearly defined training require-ments, to enable practitioners of varied backgroundsto acquire the skills they need to perform these proce-dures at the point of care. Data will very likely emergeproving that ultrasound guidance improves the out-come of the vast majority of procedures, includingthose discussed in this chapter, and early adapterswill have a distinct advantage.

References1. Rao S, van Holsbeek L, Musial JL, et al. A pilot study of

comprehensive ultrasound education at Wayne StateUniversity School of Medicine: a pioneer year review.J Ultrasound Med. 2008;27(5):745–749.

2. Hoppmann R, Cook T, Hunt P, et al. Ultrasound in med-ical education: a vertical curriculum at the University ofSouth Carolina School of Medicine. J S C Med Assoc.2006;102(10):330–334.

3. Jones PW, Moyers JP, Rogers JT, et al. Ultrasound guidedthoracentesis: is it a safer method? Chest. 2003;123(2):418–423.

4. Mayo PH, Goltz HR, Tafreshi M, et al. Safety of ultra-sound guided thoracentesis in patients receivingmechanical ventilation. Chest. 2004;125(3):1059–1062.

5. Feller-Kopman D. Ultrasound-guided thoracentesis.Chest. 2006;129(6):1709–1714.

6. McGee DC, Gould MK. Preventing complications ofcentral venous catheterization. N Engl J Med. 2003;348:1123–1133.

7. Polderman KH, Girbes AJ. Central venous catheter use.Part 1: mechanical complications. Intensive Care Med.2002;28:1–17.

8. Merrer J, De Jonghe B, Golliot F, et al. Complications offemoral and subclavian venous catheterization in criti-cally ill patients: a randomized controlled trial. JAMA.2001;286:700–707.

9. Mansfield PF, Hohn DC, Fornage BD. Complications andfailures of subclavian vein catheterization. N Engl J Med.1994;331:1735–1738.

10. Light RW. Pleural Diseases. 5th ed. Philadelphia, PA:Lippincott Williams & Wilkins; 2007.

11. Legler D, Nugent M. Doppler localization of the internaljugular vein facilitates central venous cannulation.Anesthesiology. 1984;60:481–482.

12. Randolph AG, Cook DJ, Gonzales CA, et al. Ultrasoundguidance for placement of central venous catheters: ameta-analysis of the literature. Crit Care Med. 1996;24:2053–2058.

13. Hind D, Calvert N, McWilliams SR, et al. Ultrasoniclocating devices for central venous cannulation: meta-analysis. BMJ. 2003;327–361.

14. Feller-Kopman D. Ultrasound-guided internal jugularaccess. Chest. 2007;132:302–309.

15. Maecken T, Grau T. Ultrasound imaging in vascularaccess. Crit Care Med. 2007;35:s178–s185.

16. Milling TJ Jr, Rose J, Briggs WM, et al. Randomized, con-trolled clinical trial of point-of-care limited ultrasonogra-phy assistance of central venous cannulation: the thirdsonography outcomes assessment program (SOAP-3)trial. Crit Care Med. 2005;33:1764–1769.

17. NICE guidelines. Available at: http://www.nice.org.uk/nicemedia/pdf/Ultrasound_49_GUIDANCE.pdf. AccessedDecember 20, 2007.

18. AHRQ evidence based practice. Available at: http://www.ahrq.gov/clinic/ptsafety/pdf/chap21.pdf. AccessedDecember 20, 2007.

19. Wigmore TJ, Smythe JF, Hacking MB, et al. Effect of theimplementation of NICE guidelines for ultrasoundguidance on the complication rates associated withcentral venous catheter placement in patients present-ing for routine surgery in a tertiary referral centre. BrJ Anesthesiol. 2007;99(5):662–665.

20. Muhm M. Ultrasound guided central venous access(letter). BMJ. 2002;325:1374–1375.

21. Forauer A, Glockner J. Importance of US findings in accessplanning during jugular vein hemodialysis catheter place-ments. J Vasc Interv Radiol. 2000;11:233–238.




22. Lee AC, Thompson C, Frank J, et al. Effectiveness of anovel training program for emergency medicine resi-dents in ultrasound-guided insertion of central venouscatheters. CJEM. 2009;11(4):343–348.

23. Blaivas M, Video analysis of accidental arterial cannula-tion with dynamic ultrasound guidance for centralvenous access J Ultrasound Med. 2009;28(9):1239–1244.

24. Levitov AB, Aziz S, Slonim AD. Before we go too far: ultra-sound-guided central catheter placement. Crit Care Med.2009;37(8):2473–2474.

25. Phelan M, Hagerty D. The oblique view: an alternativeapproach for ultrasound guided central line placement.J Emerg Med. 2008;37(4):403-8.

26. Mermel LA. Prevention of intravascular catheter-relatedinfections. Ann Intern Med. 2000;132:391–402.

27. Mayo PH, Doelken P. Pleural ultrasonography. Clin ChestMed. 2006;27:215–227.

28. Sandhu NS. Transpectoral ultrasound-guided catheteri-zation of the axillary vein: an alternative to standardcatheterization of the subclavian vein. Anesth Analg.2004;99:183–187.

29. Mackey SP, Sinha S, Pusey J. Ultrasound imaging of theaxillary vein-anatomical basis for central access (letter).Br J Anaesth. 2003;93:598–599.

30. Galloway S, Bodenham A. Ultrasound imaging of the axil-lary vein-anatomical basis for central venous access. BrJ Anaesth. 2003;90:589–595.

31. Sharma S, Bodenham AR, Mallick A. Ultrasound-guidedinfraclavicular axillary vein cannulation for centralvenous access. Br J Anaesth. 2004;93:188–192.

32. Bogin IN, Stulin ID. Application of the method of 2-dimensional echospondylography for determininglandmarks in lumbar punctures. Zh Nevropatol PsikhiatrIm S S Korsakova. 1971;71(12):1810–1811.

33. Cork RC, Kryc JJ, Vaughan RW. Ultrasonic localization ofthe lumbar epidural space. Anesthesiology. 1980;52(6):513–516.

34. Currie JM. Measurement of the depth to the extraduralspace using ultrasound. Br J Anaesth. 1984;56(4):345–347.

35. Grau T, Leipold RW, Conradi R, Martin E, Motsch J.Efficacy of ultrasound imaging in obstetric epiduralanesthesia. J Clin Anesth. 2002;14:169–175.

36. Grau T, Leipold RW, Conradi R, Martin E, Motsch J.Ultrasound imaging facilitates localization of theepidural space during combined spinal and epiduralanesthesia. Reg Anesth Pain Med. 2001;26(1):64–67.

37. Grau T, Leipold RW, Fatehi S, Martin E, Motsch J. Real-time ultrasonic observation of combined spinal-epiduralanaesthesia. Eur J Anaesthesiol. 2004;21(1):25–31.

38. Ferre RM, Sweeney TW, Strout TD. Ultrasound identifica-tion of landmarks preceding lumbar puncture: a pilotstudy. Emerg Med J. 2009;26(4):276–277.

39. Crogan DR, Irwin RS, Channick R. Complications associ-ated with thoracentesis: a prospective, randomized

study comparing three different methods. Arch InternMed. 1990;150:873–877.

40. Weingarde JP, Guico RR, Nemcek AA Jr, Li YP, Chiu ST.Ultrasound findings following failed, clinically directedthoracentesis. J Clin Ultrasound. 1994;2:419–426.

41. Yang PC, Luh KT, Chang DB, et al. Value of sonography indetermining the nature of pleural effusion: analysis of320 cases. AJR Am J Roentgenol. 1992;159:29–33.

42. Vignon PV, Chastagner C, Berkane V, et al. Quantitativeassessment of pleural effusion in critically ill patients bymeans of ultrasonography. Crit Care Med. 2005;33(8):1757–1763.

43. Nicolaou S, Talsky A, Khashoggi K, et al. Ultrasoundguided interventional radiology in critical care. Crit CareMed. 2007;35(suppl):S186–S197.

44. Irwin RS, Rippe JM, Cerra, FB, Curley FJ, Heard, SO.Procedures and Techniques in Intensive Care Medicine. 3rd ed.Philadelphia, PA: Lippincott William & Wilkins;1999.

45. Feller-Kopman D. Ultrasound-guided thoracentesis.Chest. 2006;129:1709–1714.

46. Lichtenstein D. Ultrasound in the management of thoracicdisease. Crit Care Med. 2007;35(5):S250–S261.

47. Reissig A, Kroegel C. Accuracy of transthoracic sonogra-phy in excluding post-interventional pneumothorax andhydropneumothorax comparison to chest radiography.Eur J Radiol. 2005;53(3):463–470.

48. Feller-Kopman D, Berkwitz D, Boiselle P, et al. Large-volume thoracentesis and the risk of re-expansion pul-monary edema. Ann Thorac Surg. 2007;84:1656–1662.

49. Nazeer SR, Dewbre H, Miller AH. Ultrasound-assistedparacentesis performed by emergency physicians vs thetraditional technique: a prospective randomized study.Am J Emerg Med. 2005;23(30):363–367.

50. Chongtham DS, Singh MM, Kalantri SP, Pathak S, Jain AP.Accuracy of clinical maneuvers in detection of minimalascites. J Indian J Med Sci. 1998;52:514–520.

51. Bard C, Lafortune M, Breton G. Ascites: ultrasound guid-ance or blind paracentesis? CMAJ. 1986;135:209–210.

52. Thomsen TW, Shaffer RW, White B, et al. Videos inclinical medicine paracentesis. N Engl J Med. 2006;355(19):e21.

53. Goldberg BB, Goodman GA, Clearfield HR. Evaluation ofascites assisted by ultrasound. Radiology. 1970;96:15–22.

54. Rumack CM, Wilson SR, Charboneau JW. DiagnosticUltrasound. 3rd ed. St. Louis, MO: Elsevier Mosby;1998.

55. Levitov AB, Aziz S, Slonim AD. Before we go too far: ultra-sound guided central line placement. Crit Care Med.2009;37:2473–2474.

56. Webster ST, Brown KL, Lucey MR, et al. Hemorrhagiccomplications of large volume abdominal paracentesis.Am J Gastroenterol. 1996;91(2):366–368.

57. Thorwarth, Jr, WT(Editorial panel chair). CurrentProcedural Terminology (professional edition). Chicago:AMA press/Elsevier; 2009.


CHAPTER 18 Ultrasound Guidance for Common Procedures · Ultrasound Guidance for Common Procedures...

Documents

Transcript of CHAPTER 18 Ultrasound Guidance for Common Procedures · Ultrasound Guidance for Common Procedures...