1 Institute of Legal Medicine, 2 Department of Anatomy and 3 Department of Anaesthesiology,Medical School Hannover, D-30623 Hannover, Germany
*Corresponding author. E-mail: albrecht.knut@mh-hannover.de
Accepted for publication: May 29, 2003
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Abstract |
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Methods. We set out to confirm this radiographic landmark in 39 fresh cadavers (age 58.4 (3.4) (mean and SE) yr) and to compare the results with those from ethanolformalin-fixed cadavers.
Results. We found that the carina was 0.8 (0.05) cm above the pericardial sac as it transverses the SVC. In no case was the carina inferior to the pericardial reflection and our study confirmed the previous findings. All the measured distances were significantly greater in fresh cadavers.
Conclusions. We confirm that the carina is a reliable, simple anatomical landmark that can be identified in vivo for the correct placement of CVCs outside the boundaries of the pericardial sac.
Br J Anaesth 2004; 92: 757
Keywords: autopsy; complications, cardiac tamponade; equipment, central venous catheters; heart, pericardium
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Introduction |
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Material and methods |
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After opening the rib cage and keeping the pericardium intact, the sternum and the medial parts of the ribs were removed. Extrapericardial fat tissue was displaced and a lambda-shaped incision was made in the pericardium. The dimensions of the intrapericardial part of the SVC and the medial side of the SVC (where a duplication of the pericardium strengthens the vessel wall) were measured in situ. We took care to avoid any stretching of the heart, blood vessels and the soft tissue to achieve reproducible results. The thoracic organs (tongue, the organs of the neck, heart, and lungs) were removed en bloc. While observing these organs from the dorsal aspect, the carina was palpated and a small metal cannula was inserted and pushed anteriorly towards the carina. The organs were then turned to inspect the ventral aspect and the distance was measured between the cannula tip (at a right angle) and the pericardium where it transversed the SVC (Fig. 1).
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Results |
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Discussion |
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To prevent such complications, especially cardiac tamponade, many suggestions have been made for assessing correct placement of CVCs,12 20 most based on clinical investigations and analysis of x-rays of the chest. However, the pericardial sac is not visible radiographically, so reliable landmarks are needed to allow reliable radiographic checking of adaequate positioning. Schuster and colleagues12 showed that the carina can be used, because in all cases the pericardium crossed the SVC below this point, which can be seen on x-ray. Keeping the CVC tip outside the boundaries of the pericardial sac will avoid perforation of the intrapericardial part of the SVC or the right atrium or ventricle. Schuster and colleagues also emphasized that the lateral side of the SVC was weaker because there was no strengthening by the pericardium. Radiological confirmation that the CVC tip is above the level of the carina may reduce the risk of pericardial perforation.
We studied the three distances in cadavers, where death had taken place up to 48 h before the investigations started, allowing almost authentic anatomical conditions. Our results confirmed the report of Schuster and colleagues,12 but we found significantly greater distances. Embalming solutions containing formalin cause tissue to shrink. Comparison of our measurements with those of Schuster and colleagues12 shows that all the dimensions in our study were greater than in the fixed anatomical cadavers (Fig. 2). In all fresh cadavers the pericardial boundaries were below the border of the carina. The point for a safe position of the catheter tip, outside the boundaries of the pericardial sac, or above the part where the pericardium fortifies the vessel wall of the SVC, should be at least 4 cm above the carina. It is important that we found no relationship between the lengths measured in the thorax and body height or sex.
Our study strengthens the case for the carina as a safe landmark in CVC placement. Pericardial tamponade after insertion of a CVC is a rare, but often fatal complication. Tamponade will be unlikely if all catheter tips are seen to be above the carina tracheae on chest x-ray.
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Acknowledgements |
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References |
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2 Dane TEB, King EG. Fatal cardiac tamponade and other mechanical complications of central venous catheters. Br J Surg 1975; 62: 6[ISI][Medline]
3 Frei U, Bussmann WD. Die Herzbeuteltamponade, eine meist tödliche Komplikation zentraler Venenkatheter. Dtsch Med Wochenschr 1981; 106: 835[ISI][Medline]
4 Hauri-Bionda R, Strehler M, Bär W. Herzbeuteltamponade infolge Verletzung der Aorta ascendens als seltene Komplikation einer zentralvenösen Katheterisierung. Rechtsmedizin 2000; 10 (Suppl 1): 13
5 Quiney NF. Sudden death after central venous cannulation. Can J Anaesth 1994; 41: 5135[Abstract]
6 Schneider V, Maxeiner H. Herzbeuteltamponade durch zentralen Venenkatheter. In: Barz J, Bösche J, Frohberg H, Joachim H, Käppner R, Mattern R, eds, Fortschritte der RechtsmedizinFestschrift für Georg Schmidt. Berlin: Springer, 1983; 11622
7 Brown CA, Kent A. Perforation of right ventricle by polyethylene catheter. South Med J 1956; 49: 4667
8 Collier PE, Goodman GB. Cardiac tamponade caused by central venous catheter perforation of the heart: a preventable complication. J Am Coll Surg 1995; 181: 45963[ISI][Medline]
9 Hayden L, Steward GR, Johnson DC, Fisher MM. Transthoracic right atrial cannulation for total parenteral nutrition-case report. Anaesth Intens Care 1981; 9: 537[ISI][Medline]
10 Hunt R, Hunter TB. Cardiac tamponade and death from perforation of the right atrium by a central venous catheter. Am J Roentgenol 1988; 151: 1250
11 Rutherford JS, Merry AF, Occleshaw CJ. Depth of central venous catheterization: an audit of practice in a cardiac surgical unit. Anaesth Intens Care 1994; 22: 26771[ISI][Medline]
12 Schuster M, Nave H, Piepenbrock S, Pabst R, Panning B. The carina as a landmark in central venous catheter placement. Br J Anaesth 2000; 85: 1924
13 Karnauchow PN. Cardiac tamponade from central venous catheterization. Can Med Assoc J 1986; 135: 11457[Medline]
14 Fletcher SJ, Bodenham AR. Safe placement of central venous catheters: where should the tip of the catheter lie? Br J Anaesth 2000; 85: 18891
15 Dollery CM, Sullivan ID, Bauraind O, Bull C, Milla PJ. Thrombosis and embolism in long-term central venous access for parenteral nutrition. Lancet 1994; 344: 10435[ISI][Medline]
16 Flatley ME, Schapira RM. Hydromediastinum and bilateral hydropneumothorax as delayed complications of central venous catheterization. Chest 1993; 103: 19146[Abstract]
17 Puel V, Caudry M, Le Metayer P, et al. Superior vena cava thrombosis related to catheter malposition in cancer chemotherapy given through implanted ports. Cancer 1993; 72: 224852[ISI][Medline]
18 Raad II, Khalil SM, Costerton JW, lam C, Bodey GP. The relationship between the thrombotic and infectious complications of central venous catheters. JAMA 1994; 271: 101416[Abstract]
19 Timsit JF, Farkas JC, Boyer JM, et al. Central vein catheter related thrombosis in intensive care patients: incidence, risk factors and relationship with catheter-related sepsis. Chest 1998; 114: 20713
20 Waghorn DJ. Intravascular device associated infection. A 2 year analysis of cases in a district general hospital. J Hosp Infect 1994; 28: 91101[ISI][Medline]