Journal of Hematology - Supplements - Haematologica

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that short-term artificial nutrition does not
decrease the complication rate in cancer patients
receiving chemotherapy or radiation; by contrast,
in patients given parenteral nutrition, there is an
increase in infections, related to the central line.
In bone marrow-transplanted patients, PN does
not decrease treatment toxicity, infection rates,
graft-versus-host disease, and only one RCT
demonstrated a better long-term survival and a
decreased tumor relapse rate. PN used as an
adjuvant therapy, conferred no advantage to children
with cancer if malnutrition had been treated
before the specific therapy: that is, it is likely
to have a better result if malnutrition is corrected.
In one trial and in other uncontrolled studies,
PN was associated with improved nutritional status
(weight gain). In well-nourished children with
cancer, the weight gain reflects increased deposition
of fat rather than of lean body mass: a
higher calorie intake in a well-nourished patient
is associated with an increased fat deposition, as
indeed expected. The results of the studies seem
to indicate the absence of any real benefit of artificial
nutrition on outcome, especially if there is
no malnutrition. 1,6
Nevertheless, it is reasonable that nutritional
support contributes to maintaining hydration,
reducing lean body mass loss, increasing patient
comfort and improving survival in patients who
can not eat or absorb for a prolonged period of
time, in patients with malnutrition or at risk of it.
The benefit in non-compromised patients is less
evident, if disease outcome parameters are the
endpoints. However, the aim of nutritional support
should be the avoidance or treatment of
malnutrition and not the treatment of the underlying
disease; from this point of view, it is likely
that nutritional support is beneficial in critically
ill patients undergoing a hyercatabolic procedure
such as bone marrow transplantation. Nutritional
support must improve the nutritional status,
while keeping technical and metabolic complications
related to the line care to a minimum.
Artificial nutrition can be delivered enterally
(enteral nutrition, EN) or through a venous central
line (parenteral nutrition, PN). The relative
benefit of EN versus PN has been widely discussed
but so far no data have convincingly
shown that EN is better than PN. Enteral nutrition
is supposed to be safer, cheaper, more physiologic,
to promote normal gastrointestinal
function, to prevent bacterial translocation and
to be associated with better outcomes than parenteral
nutrition, but so far no study has been
conclusive . In a recent meta-analysis on critically
ill patients, PN was not associated with a
worse outcome, and many other studies, performed
in different patients, failed to show a
real benefit of enteral nutrition, so the choice
between enteral and parenteral nutrition seems
to be based on team experience, patient’s feeding
tolerance, presence of intestinal obstruction,
and need for prolonged intravenous therapy.
However, if there is an indication for artificial
support, enteral nutrition should be considered
as the first choice. 1,2,5
In patients undergoing bone marrow transplantation,
the complications related to
chemotherapy and radiation could represent a
formal indication for parenteral nutritional support,
because anorexia, vomiting, and enteritis
can interfere with feeding tolerance. The prolonged
intravenous therapies require, especially
in children, the presence of a central venous line
which is also useful for nutrition. PN is a safe
technique for nutrition, but the rate of complications
must be considered. Technical complications
are sepsis and line/venous obstruction;
the metabolic complications include hyper- and
hypoglycemia, electrolyte disturbances, liver disease,
and osteopenia. 1,2
The most frequent complications are those
related to the infusion line, especially infections;
handwashing and aseptic technique in the management
of the line are the basic principles of
infection control. Large studies showed that not
only is the aseptic management of the line important
to minimize the risk of infection but also its
correct placement. Controlled studies have
demonstrated the benefit of placement in the
operating room, using good barrier precautions,
i.e. masks, cap, sterile gloves, gown and a large
drape to cover the insertion site. With such a protocol,
the colonization rates dropped from 1.0
per 1,000 days to 0.3 per 1000 days. The
catheter-related sepsis rate was 6.3 times higher
in untreated groups. Catheter tunnelling seems
to play a role in preventing sepsis but not such an
important and relevant one as the role of the
nutritional team. Many studies have strongly suggested
that the presence of a motivated nursing
team using the correct aseptic technique in managing
the line is the best prevention of catheterrelated
sepsis; far less important are the new
catheters, silver-chelated or antibiotic impregnated
lines. In contrast, the use of the new
needleless system for the closure of the line offers
a significant advantage in terms of nursing and
patient safety: the needleless devices permit connection
to the line without opening the catheter,
thus reducing the risk of infection, and also of
blood reflux (the system is always closed). The
concerns about the increased risk of infection
arose from the first experiences, but further studies
have clearly indicated a drop in infection rates
if the device is changed at least every 72 hours. 7
Metabolic complications are frequent and
require careful monitoring; in critical care
haematologica vol. 85(supplement to n. 11):November 2000