Correspondence Anaesthesia, 2003, 58, pages 385–402
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Thirteen centimetre central
venous catheters, lucky for all?
caval cava-atrial junction during central
venous catheter placement. Critical Care
Medicine 2000; 28: 138–42.
consecutive left-sided lines found that
all were 16 cm long and none were
intra cardiac using the carina as the
landmark [3]. The catheter tips of the
majority (70%) were closely adjacent
and acutely angled towards the right
border of the SVC. This abutment to
the wall of the SVC was common in
catheters placed anywhere between 13
and 16 cm. Two catheters had obvi-
ously damped pressures traces, presum-
ably due to occlusion of the tip by the
right lateral wall of the SVC. The best
position is probably in the lower SVC,
parallel to the wall of the SVC but still
extracardiac. In the majority of patients
catheters would have needed to be a 1–
2 cm longer to be located in this ideal
position.
It seems there is a fixation with the
one-size-fits all mentality. In fact 16 cm
catheters are too long for the right-sided
approach, with the need to have 3 cm
dangling from the patient, and too short
for the left sided approach with acute
angulation and risk of erosion of the
SVC.
Ideally a 13-cm length of catheter
could be used for right-sided access,
reassured that intra cardiac placement is
virtually eliminated. For left-sided access
16 cm catheters are too short. An 18 or
20 cm catheter would allow for place-
ment to a range of positions guided by
chest X-ray findings that simultaneously
meets the needs to avoid either intra
cardiac placement or SVC erosion and
perforation.
There continues to be debate on the
correct placement of central lines (Pol-
lard & Johnson. Anaesthesia 2002; 57:
1223). Some years ago in our intensive
care unit we changed to 16 cm cathe-
ters because it had been shown that
20 cm catheters were very frequently
placed into the heart [1,2]. However,
despite this change, like Pollard [1], we
found there was still a high incidence of
intracardiac placement of central venous
catheters.
As the average distance from the right
internal jugular vein (RIJV) to the
atriocaval junction is 16 cm [1], then if
catheters are placed to 16 cm one would
expect to find that half will be within the
atrium. McGee [1] found that 7 of 38
(16%) 16 cm catheters placed via the
RIJV and 4 of 18 (18%) via the right
subclavian vein were intracardiac. Esti-
mates from this work indicated that if
central catheters are placed to 13 cm one
could be 95% confident that the line will
not be intra cardiac.
Therefore in December 2000 in
Leicester the anaesthetic department
adopted guidance that all right-sided
catheters should be placed to a maxi-
mum insertion of 13 cm. Since that
time, over 2000 catheters have been
placed. The number of catheters that
have been identified as having an intra-
cardiac location has been less than 1%,
and all of those have been placed more
than 13 cm for various reasons (i.e.
large patient, low approach). The sim-
ple step of placing right-sided central
catheters to a maximum of 13 cm,
virtually eliminates the risk of the
catheter tip being intracardiac.
3 Schuster M, Nave H, Piepenbrock A,
Pabst R, Panning B. The carina as a
landmark in central venous placement.
British Journal of Anaesthesia 2000; 85:
192–4.
Critical incident involving an
adjustable tracheostomy tube
A tracheostomy is a recognised aid to
weaning from artificial ventilation.
Many tracheostomies are now per-
formed percutaneously in the intensive
care unit, although some patients still
require a formal tracheostomy. I would
like to report a critical incident that
occurred during such a procedure.
A 70-year-old woman was admitted
to the intensive care unit following a
cardiac arrest. Weaning from ventilation
was complicated by recurrent pulmon-
ary oedema, and a tracheostomy was
planned. She was unsuitable for a per-
cutaneous tracheostomy, as she had a
previously unnoticed thyroid goitre,
and a formal tracheostomy was per-
formed in theatre. Intra-operatively, it
was noticed that the distance from the
skin to the trachea was greater than
usual due to her goitre. The surgeon
therefore decided to insert an adjustable
tracheostomy tube (Portex – size 8
profile cuff, adjustable flange tube –
see Fig. 2). On this tube, the position of
the flange can be adjusted, altering the
distance from the curve of the tube to
the flange. The tube was placed through
the tracheostomy and the flange adjus-
ted to rest on the skin. As the tracheal
incision was made at the third tracheal
ring, we were concerned that the end of
the tube might be impinging on the
W. C. Russell
J. L. Parker
Leicester Royal Infirmary,
Leicester LE1 5WW, UK
E-mail: williamcarnduff@yahoo.co.uk
Left sided catheters are more com-
plex, requiring negotiation of two junc-
References
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short length of superior vena cava
(SVC). The distance to the heart from
the left (IJV or SCV) being between
19 cm and 21 cm [2], it is relatively easy
to ensure the catheter is clear of the
LR, Prasad VM, Bandi V, Mallory DL. bronchoscope, and the tube was with-
Accurate placement of central venous
catheters: a prospective, randomized,
multicenter trial. Critical Care Medicine
1993; 8: 1118–23.
drawn to lie with its tip 2 cm above the
carina. The flange was readjusted to
rest against the skin and was sutured
into position using the anchor points
heart with the usual length catheters. 2 Andrews RT, Bova DA, Venbrux AC. supplied.
However, acute angulation of the cath-
eter tip as it abuts the right lateral wall
of the superior vena cava (SVC) is
common. A review of the last 27
How much guidwire is too much?
Direct measurement of the distance
from subclavian and internal jugular
vein access sites to the superior vena
After completion of surgery, the
tracheostomy tube was reconnected to
our portable Oxylog ventilator. The
ventilator circuit, which has a bulky
388
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