MISDIRECTED CENTRAL VENOUS CATHETER

Scenario 1. A 23 yr old patient with antepartum hemorrhage was taken to OT for Caesarean section. She had profuse bleeding on table  but could be controlled following delivery of baby, with blood transfusion and colloids. The chest on auscultation revealed fine basal creps and she had persistent hypotension.A central venous catheter was introduced through the right internal jugular vein. Confirmation of placement done by aspiration for free flow and rapid infusion of fluids.But the free flow was not obseved at a catheter length of 14 cm or13 cm but free flow observed at 11 cm.The patient remained ventilated and was shifted to the icu and CXR was  taken The tip of the catheter appeared to be in the right subclavian vein  with a slight angulation. A repeat procedure was deferred as the patient had coagulopathy and that the clinical confirmatory tests are satisfactory. The next day afternoon patient was complaining of raspiratory distress with tachypnea and pain on right side of chest. Auscultation revealed absent breath sounds on right side  with dullness on percussion. A repeat CXR showed  displacement of catheter tip, with massive pleural effusion on the right side which was drained subsequently.

Scenario 2. A 30 year old patient was admitted with h/o road traffic accident.His GCS was 13 and he complained of abdominal pain. A tender and rigid abdomen was noted  the pulse rate was 122/mt  and BP was 90/50.A diagnosis of blunt injury abdomen was made USG abdomen was done and fluid resuscitation started.Soon he collapsed  and was taken for emergency laparotomy. Central venous catheter inserted through right internal jugular and free flow confirmed. Blood and fluids were infused at moderate speed. Surgery over, resuscitation was complete and patient was shifted to icu for post operative care. CXR ordered.   In the icu he had bleeding from the site of insertion of central line and infusion of fluids got obstructed.Aspiration and bright red colour of the blood raised the suspicion of arterial cannulation. ABG was confirmatory. Central line was removed and a right subclavian line secured 

Scenario 3. An 80 year old patient with h/o CVA and unconsciousness required central line as she had ischemic changes in ECG and  because the  peripheral veins are flimsy.Post procedure CXR showed the catheter tip in Rt. internal jugular vein.

In the first Scenario, the possible explanation for catheter migration into the pleural cavity could be as follows:

The catheter was in right subclavian artery and as the systemic pressure was very low it allowed free flow of fluid and back flow. The oxygen saturation will be obviously low in severe hemorrage so bright red colour of the blood was masked .As the systemic pressure improved with fluid resuscitation and with infusion of inotrops, the ejection  force transmitted to the catheter by aorta made a dislodgement of the catheter and subsequent erosion  into the pleural cavity and the IV infusion caused a massive pleural effusion.The same mechanism ie. internal carotid artery cannulation, operated in the second scenario but leak around the catheter when BP improved with bright red colour of the blood lead to early detection of misplacement.The third scenario shows procedure related migration of central venous catheter into the right IJV.

Central venous cannulation is an indispensable monitoring tool in the management of critically ill patients.     Of the several approaches for insertion, the subclavian route is considered as the classic procedure.During the procedure misdirection or migration of the catheter, eventhough rare, can cause some complications.

The most commonly observed malpositioning is, the catheter is directed cephalad into the ipsilateral internal jugular vein .Other sites for malpositioning mentioned in literature include the azy­gos vein, left superior intercostal vein, hemiazygos vein, lateral thoracic vein, inferior thyroid vein, left superior intercostal vein, thymic vein, and pleural cavity [1] . Contralateral subclavian is an extremely unusual site for malpositioning Malpositioning  may not serve the purpose of insertion and most often needs revision of the procedure.It is both time and resource consuming. Misplacement of the catheter tip can enhance the risk of clot formation and cause thrombophlebitis. The other complication is catheter migration, which is uncommon but dangerous . The catheter can erode into the pleural cavity as in the first case or a catheter abutting the wall of superior vena cava can cause perforation and profuse hemorrhage.It was seen that carotid artery puncture occurred in 8.3% of patients undergoing internal jugular vein cannulation.[2]

CXR showing catheter malposition into contralateral subclavian vein in a trauma victim.

How to prevent Malposition during the procedure?

                                        The positioning of guidewire has a role. A randomized, controlled study, suggest that keeping the guide wire J-tip di­rected caudad increased correct placement of central venous catheters towards the right atrium [3]. It was also postulated that there is a relationship between the length of the guidewire and catheter malposition. Some authors impli­cate excessive guidewire length as cause for this complication and recommends a guidewire length of 18 cm which should be con­sidered as the upper limit  [4].It is also seen that a steep head low to fill the central lines is associated with increased venous pressure which preferentially direct the floating guidewire to the neck veins.

How to detect Malposition while placing?

• Aspiration of blood;  free flow should be tested using a syringe of at least 20 mL in volume,and the aspiration of blood should be without resistance (or back flow into the infusion aided by gravity.)
• Rapid infusion of saline,unobstructed flow
• Observing the ECG tracings during guidewire placement, configuration of  'p' wave.
• Observing the classic central venous pressure tracings
• Using the real-time ultrasound guided technique for puncturing and cannulating the internal jugular vein [5] It has been shown that under ultrasound guidance, the jugular vein could be entered on the first attempt in 83.3% of patients.
• Using a doppler probe (the one used by obstetricians for fetal monitoring may suffice)[6] 
• Endocavitory ECG , can guide correct placement of catheter in superior vena cava.Here the catheter is connected to the ECG recorder wire to record ECG in Lead II, considered as an alternate method to check the position of the catheter. When the catheter enters the right atrium, there is a large increase in the amplitude of P wave.This technique is cheaper, and of similar efficacy to the radiological method. Endocavitary ECG can replace chest X-rays to check the position of the catheter in more than 90% of cases[7]
• Fluoroscopic guidance during the procedure helps to assess the position of the catheter, any vascular abnormalities or stenosis and can be used to find out misplaced catheter.
• The simple technique for detection is called The IJV occlusion test: After placement occlude the IJV by external pressure over the neck(in the supraclavicular area for approximately 10 sec.A flattened trace  and increase in CVP of approximately 5 mmHg suggests misplacement of catheter into IJV.This is especially useful for subclavian vein cannulation[8]
• Another simple and sensitive bed side method for detection is the 'Saline flush test'.Used to detect subclavian catheter malposition in IJV. Flush test was performed by injecting 10 ml of normal saline in the distal port of catheter, while anterior angle of ipsilateral neck was palpated by an independent observer. A thrill of fluid elicited on the palm of hand (positive test) was suggestive of catheter misplacement.This may be confirmed by fluroscopy[9]

          Fig: demonstrating the saline flush test, By courtesy of Ref  [9]                                            

• CXR: A post procedural CXR is the most commonly used method to find catheter malposition.A positon at the junction of the the superior vena cava and right atrium is considered ideal, where the catheter tip is imaged just above the carina.In suspected cases of catheter migration a lateral CXR is also indicated.The unusual position of catheter as in the internal mammary vein will be located more laterally, the pericardio phrenic vein will follow the left cardiac border,and the superior intercostal vein will follow the aortic knob and frequently reveal an aortic nipple,while the superior intercostal vein will occupy the posterior mediastinal position in lateral view.
• Other techniques for detection of malposition are CT scan or venography but are employed when other measures are failed

 How to correct Malpositioning or Misdirection after placement?
 
The author prefers the following procedure.The patient may be positioned semirecumbent my minimal  elevation of the head end of the cot.  The central venous catheter (CVC) is withdrawn upto 4-5 cm mark   A fresh guidewire is inserted through the catheter but advanced upto12-14 cm only.The new CVC is then  reinserted after applying pressure over the ipsilateral IJV.Always use a new CVC as guidewire can damage the previous catheter while insertion.Subsequently a flush test or IJV occlusion test may be performed to assess the positon.The CXR is now repeated.A risk of air embolism is there associated with minimal head up position but rare and all precautions should be taken.

Related post: Supraclavicular CVC insertion,  http://anaesthesiatoday.blogspot.com/2010/02/central-venous-cannulation-which-route.html

Ref:1) Currarino G. Migration of jugular or subclavian venous catheters into inferior tributaries of the brachiocephalic veins or into the azygos vein, with possible complica­tions. Pediatr Radiol 1996 ;26:439-49.

      2) Denys BG, Uretsky BF, Reddy PS. Ultrasound-assisted cannulationof the internal jugular vein. A prospective comparison to the externallandmark-guided technique. Circulation 1993;87:1557-62.
      3) Tripathi M, Dubey PK, Ambesh SP. Direction of the J-tip of the guidewire, in seldinger technique, is a significant factor in misplacement of subclavian vein catheter: a ran­domized, controlled study. Anesth Analg 2005 ;100:21-4.
      4) Andrews RT, Bova DA, Venbrux AC. How much guidewire is too much? Direct measurement of the dis­tance from subclavian and internal jugular vein access sites to the superior vena cava-atrial junction during cen­tral venous catheter placement. Crit Care Med 2000 ;28:138-42.
     5)  Farrell J, Gellens M. Ultrasound-guided cannulation versus the landmark-guided technique for acute haemodialysis access. Nephrol Dial Transplant 1997;12:1234-7.
     6)  Paul Marino The ICU Book 3rd edition
     7)Calabuig R, Sueiras A, Galera MJ, Ortiz C, Pi F, Sierra E. Central venous catheter location by endocavitary ECG: an alternative to chest radiography Med Clin (Barc). 1997 Sep 20;109(9):324
     8)Ambesh SP, Pandey JC, Dubey PK, Internal jugular vein occlusion test for rapid diagnosis of misplaced subclavian vein catheter into the internal jugular vein. Anesthesiology. 2001 Dec;95(6):1377-9.
    9)G P Rath, P K Bithal, G R Toshniwal, H Prabhakar, H H Dash Rath GP, Bithal PK, Toshniwal GR, Prabhakar H, Dash HH."Br J Anaesth. 2009 Apr;102(4):499-502. Epub 2009 Feb 25".Saline flush test for bedside detection of misplaced subclavian vein catheter into ipsilateral internal jugular vein.

Post image by courtesy of   AZ Rainman;  www.freakingnews.com/Necks-Pictures--1489-0.asp