Correspondence

Some tricks in iatrogenic pneumothorax?

American Journal of Emergency Medicine 33 (2015) 970-982

References

Contents lists available at ScienceDirect

American Journal of Emergency Medicine

journal homepage:

We read the article of Vinson et al [1] titled “Pneumothorax is a rare complication of thoracic central venous catheterization in community EDs.” We thank the authors about their well-designed study.

Iatrogenic pneumothorax that occurred during central vein cathe- terization is generally related to the experience of the practitioner. When it becomes a routine for the practitioner, the number of iatrogenic pneumothorax decreases. However, we think that, in a teaching hospi- tal, the incidence of this complication cannot be decreased because of the continuity of the education.

Insertion of a needle to the lung does not always cause pneumothorax. It is declared that pneumothorax incidence after transthoracic needle bi- opsy is approximately 20% in general [2]. The occurrence of emphysema and/or bullous formation of the lung, the diameter of the needle, the ex- tent of the needle passing the pleura, and the pleural adhesions determine the occurrence of pneumothorax in all kinds of interventional procedures to the lung including central venous catheterization. During the awake procedures of central venous catheterization, some incompatible patients may mimic symptoms of pneumothorax such as pain and shortness of breath. If the patient is stable and physical examination does not clearly reveal a pneumothorax, we should not perform an evacuation procedure, which may be unnecessary, before performing a radiological study.

In some centers, central venous catheterization is performed with the help of an ultrasound, as mentioned in the text. Ultrasound can also be used for detection of pneumothorax [3]. We think that, with the help of ultrasound, overlooked Occult pneumothorax cases can be detected.

Radiological studies are performed after the catheterization procedure to verify the position of the catheter and to determine any complication. This approach is suitable for unilateral attempts. However, if an attempt from the contralateral side is needed, we recommend radiological studies “before” a contralateral attempt in order not to struggle with the complica- tion of bilateral pneumothorax. We sometimes face bilateral pneumotho- rax after central vein catheterizations that require emergency evacuation.

Sezai Cubuka, MD Gata Medical Faculty, Department of Thoracic Surgery, Ankara, Turkey Corresponding author. Department of Thoracic Surgery

Gata Medical Faculty, Ankara, Turkey Tel.: +905424868489; fax: +903123533702

E-mail address: [email protected]

Orhan Yucel

Gata Haydarpasa Teaching Hospital, Department of

Thoracic Surgery, Istanbul, Turkey E-mail address: [email protected]

http://dx.doi.org/10.1016/j.ajem.2015.02.014

? Conflict of interest: None declared.

Vinson DR, Ballard DW, Hance LG, Stevenson MD, Clague VA, Rauchwerger AS, et al. Pneumothorax is a rare complication of Thoracic central venous catheterization in community EDs. Am J Emerg Med 2015;33(1):60-6.

Boskovic T, Stanic J, Pena-Karan S, Zarogoulidis P, Drevelegas K, Katsikogiannis N, et al. Pneumothorax after transthoracic needle biopsy of lung lesions under CT guidance. J Thorac Dis 2014;6(Suppl. 1):S99-S107.

Kumar S, Agarwal R, Aggarwal AN, Gupta D, Jindal SK. Role of ultrasonography in the diagnosis and management of pneumothorax following transbronchial lung biopsy. J Bronchol Interv Pulmonol 2015;22(1):14-9.

The indications for screening chest radiography after failed thoracic central venous catheterization

To the Editor,

We thank Drs. Sezai and Yucel for their interest in our central venous catheterization research and welcome this opportunity to respond to their recommendation to routinely obtain a postprocedural chest radiograph after an unsuccessful thoracic central venous catheterization before attempting a contralateral thoracic central line. Although the inten- tion is very well placed-avoiding iatrogenic bilateral pneumothoraces-we are not sure the incidence of this rare complication is sufficiently high to warrant a policy of universal postattempt radiography.

In our series of 1249 cases, we found a very low rate of immediate pneumothorax in patients receiving catheterization exclusively of the Internal jugular vein (0.1%) as well as in patients who did not receive positive-pressure ventilation throughout their emergency department stay (0.1%) [1]. If a nonventilated patient underwent an unsuccessful right IJ vein catheterization, followed by an attempt at catheterizing the left IJ vein, the odds of developing bilateral pneumothoraces are extremely low. Assuming even a substantially inflated incidence of 0.5% at each side, the risk of bilateral pneumothorax would be approxi- mately 1 in 40 000. Insisting on a postprocedural radiograph in every case is not without its downsides. If a patient urgently needed central venous access for time-sensitive treatment, as in a critically ill septic pa- tient without peripheral access, the further Delay in care attending addi- tional imaging may be harmful. Moreover, using the above conservative risk estimates and an estimated cost for a portable chest radiograph of US $100, at least US $4 million would be spent to prevent 1 case of bilat- eral pneumothoraces.

However, not all thoracic central line cases carry the same risk of col- lapsing a lung. The odds of pneumothorax are higher in ventilated pa- tients as well as those undergoing catheterization of the subclavian vein. In these slightly higher risk cases, if not pressed for emergent ve- nous access, it might be prudent to exclude pneumothorax on the

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index side before proceeding to catheterize the contralateral thoracic central vasculature.

In our medical group of more than 500 emergency physicians, obtaining postprocedural radiographs before moving to the contralater- al side is not routinely practiced. In our study cohort of 1249 cases, only 25 patients (2.0%) had a failed thoracic central venous catheterization on one side followed by an attempt on the contralateral side. Only 2 of these cases (8.0%) underwent interval imaging: none of the 13 patients receiving attempted IJ vein catheterization and 2 of the 12 patients re- ceiving attempted subclavian vein catheterization.

In light of the low incidence of iatrogenic pneumothorax in characteristically low-risk patients, some have questioned the need for routine radiographs even after successful thoracic central venous catheterization and have proposed restricting the indica- tions to higher risk situations [2-4]. The 2014 guidelines for the clinical management of central venous catheterization by the Swedish Society of Anaesthesiology and Intensive Care Medicine recommend a chest radiograph only “when pneumothorax or haemothorax is suspected” [5].

However, chest radiographs have not been used just for the detec- tion of iatrogenic pneumothorax. Defining the anatomical location of the catheter tip is another role played by the postprocedural film. Inter- estingly, chest radiography might not be needed here either. Ultraso- nography in the hands of trained emergency physicians can be used to assess for catheter malposition by quickly locating the tip of the central vein catheter [6]. Given the utility of ultrasound in identifying other complications of central venous catheterization, such as a pneumotho- rax or a retained guide wire, postprocedural chest radiography may no longer be necessary in all cases as a matter of course.

David R. Vinson, MD Kaiser Permanente Division of Research and The Permanente Medical Group, Oakland, CA

Department of Emergency Medicine, Kaiser Permanente Sacramento

Medical Center, Sacramento, CA, 95825

Corresponding author.

E-mail address: [email protected]

Dustin W. Ballard MD, MBE Kaiser Permanente Division of Research and The Permanente Medical Group, Oakland, CA

Kaiser Permanente San Rafael Medical Center, San Rafael, CA

Dustin G. Mark, MD

The Permanente Medical Group, Oakland, CA Kaiser Permanente Oakland Medical Center, Oakland, CA

http://dx.doi.org/10.1016/j.ajem.2015.02.013

References

1. Vinson DR, Ballard DW, Hance LG, et al. Pneumothorax is a rare complication of tho- racic central venous catheterization in community EDs. Am J Emerg Med 2015;33: 60-6.
2. Pikwer A, Baath L, Perstoft I, et al. Routine chest X-ray is not required after a low-risk central venous cannulation. Acta Anaesthesiol Scand 2009;53: 1145-52.
3. Lessnau KD. Is chest radiography necessary after uncomplicated insertion of a triple- lumen catheter in the Right internal jugular vein, using the anterior approach? Chest 2005;127:220-3.
4. Molgaard O, Nielsen MS, Handberg BB, et al. Routine X-ray control of upper central venous lines: is it necessary? Acta Anaesthesiol Scand 2004;48:685-9.
5. Frykholm P, Pikwer A, Hammarskjold F, et al. Clinical guidelines on central venous catheterisation. Swedish Society of Anaesthesiology and Intensive Care Medicine. Acta Anaesthesiol Scand 2014;58:508-24.
6. Weekes AJ, Johnson DA, Keller SM, et al. Central vascular catheter placement evalua- tion using saline flush and Bedside echocardiography. Acad Emerg Med 2014;21: 65-72.

   An alternate technique for assessing optic nerve in papilledema by ultrasound B scan

   To the Editor,

   

   We read with great interest the article entitled “Real-time optic nerve sheath diameter reduction measured with bedside ultrasound after therapeutic lumbar puncture in a patient with idiopathic intracra- nial hypertension” by Singleton et al [1]. They have described the use of ocular ultrasound in a case of idiopathic Intracranial hypertension and demonstrated real-time change in the size of the optic nerve sheath diameter after a lumbar puncture.

   Ocular ultrasound is an easy and a noninvasive bedside method of evaluating the optic nerve, routinely used by neuro-ophthalmologists and is especially helpful in the setting of increased intracranial pres- sure (ICP). Here, we describe an alternative technique used for the evaluation of optic nerve using a 10-MHz ophthalmic ultrasound (Tomey UD-6000 A/B scan). Conventionally, as in this study, scans of the optic nerves were obtained by keeping the ultrasound probe di- rectly over the closed lids, resulting in an axial scan showing the lon- gitudinal section of the optic nerve emerging from the globe [1,2]. We prefer a vertical transverse scan of the optic nerve by directly placing the ultrasound probe over the conjunctiva adjacent to temporal lim- bus, after instillation of a Topical anesthetic, precluding the need for lubricating jelly. This gives a cross section of the optic nerve enabling the measurement of transverse diameter of the optic nerve. The ad- vantage of this view over the axial scan is in bypassing the sound at- tenuation due to lens, which can sometimes interfere with the visualization of the optic nerve on the axial scans [3]. In advanced cases of papilledema, an echolucent crescent-shaped (crescent sign) or ring-shaped area (doughnut sign) can be seen around the optic nerve [4].

   We would like to illustrate a case of cerebral venous sinus thrombo- sis with raised ICP in a child where we used this technique for assessing optic nerve to monitor therapeutic response. A 6-year-old child was re- ferred to our neuro-ophthalmology clinic for Ocular examination. At the time of examination, he was being evaluated for clinical symptoms of raised ICP. On ophthalmic examination, vision in both eyes was 6/6. His external ocular examination was within normal limits with full and painless ocular movements. His fundus examination showed grade 3 papilledema (Fig. 1A). B-scan ultrasound showed increase in the size of optic nerve sheath diameter (Right eye, 6.22 mm; and Left eye, 7.20 mm) with presence of subarachnoid fluid around the optic nerves (Fig. 1B) confirming papilledema. Magnetic resonance imaging of the brain was unremarkable; however, the magnetic resonance venogram revealed complete sigmoid sinus thrombosis. He was started on anti-edema measures along with Low Molecular Weight Heparin and followed up weekly at our clinic for monitoring the resolution of papilledema. We repeated his ultrasound B scan at every visit, which progressively showed resolution of fluid around the optic nerves and decrease in the size of optic nerves. Three weeks from starting the treat- ment, his papilledema had completely resolved (Fig. 2A) with the B scan reflecting similar findings (Fig. 2B). At 1 year follow-up, he continues to remain asymptomatic. Thus, ultrasound can be effectively used as a tool to monitor therapeutic response in setting of increased ICP, in this in- stance due to a cerebral sinovenous thrombosis.

   Jyoti Matalia, MBBS, DOMS, DNB? Sheetal Shirke, MBBS, MS, DNB Narayana Nethralaya, Bangalore, Karnataka, India

   ?Corresponding author at: Department of Paediatric Ophthalmology and Strabismus, Narayana Nethralaya-2, Narayana Health City, 258/A Bommasandra, Hosur Road, Bangalore 560099 Karnataka, India

   Tel.: +91 80 66660691, +91 80 66660655

   E-mail address: [email protected]