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For
the purpose of this site I will use case studies in order to show
how DKA and HHNS may present themselves. They will be typical
cases so it is important to remember not all cases are typical.
Case
study one
Lynda
is a 45 year old type 1 diabetic. She is admitted to your unit
with a history of vomiting over the past 24 hours. You admit her
and take her observations and realise that her respirations are
fast and could be Kussmaul respirations.
Over
the past few days she has been feeling quite ill and feverish, and
has eaten little. As she was not eating, Lynda decided to omit her
insulin dose until she could eat something. Lynda was afraid she
might become hypoglycaemic, something which has happened to her
before. However, when she measured her blood glucose levels last
night and this morning they were a lot higher than usual. She has
been vomiting and when she checked her urine she found that there
were a large amount of ketones present. She contacted her G.P.
this morning and he referred her to the hospital. On carrying out
a visual assessment you realise that the patient is dehydrated.
She also appears quite lethargic.
The
doctor makes a provisional diagnoses of DKA.
Case
study two
Bob
is 69 year old man admitted to your unit following a collapse and
loss of consciousness. On admission you take his observations and
realise that his blood pressure is very low. He is rousable only
to painful stimuli. On insertion of a urinary catheter urine
output is less than 30ml per hour. You take his blood sugar level
and find that his blood glucose level is so high it is unreadable
by a capillary glucose meter. You immediately have blood taken for
a serum glucose and electrolyte level. His urine has only trace
amounts of ketones but shows some indication of infection. It also
contains large amounts of glucose. Bob seems very dehydrated on
visual assessment. On meeting the family they tell you that he has
been deteriorating in health since surgery on his knee. They say
he had put on a great deal of weight as he can no longer walk for
long distances. Additionally they admit that his knee had been
giving him a lot of pain but that he would not let the family look
at it for fear of further surgery. On examination the knee was
extremely swollen and hot to the touch. The doctor makes a
provisional diagnosis of HHNS.
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management
of complications
The
management and successful treatment of acute complications depends
on the satisfactory rectification of dehydration, hyperglycaemia,
ketoacidosis and electrolyte deficiencies.
What
Comes First?
- Fluid
replacement.
The patient with either DKA or HHNS will need fluid therapy. Both
will be dehydrated although the dehydration will usually be most
pronounced in HHNS. The main intention of fluid therapy is to
expand intravascular and extravascular volume and to restore
kidney perfusion (Chiasson 2003). This must be undertaken before
any other drug therapy as rehydration and electrolyte replacement
can reduce insulin resistance by reducing the counter regulatory
hormones and making cells less resistant to insulin therapy (Kitabchi
et al. 2001). Care should be taken over what fluid is
administered, and must depend on the state of hydration,
electrolyte levels and urinary output.
- Fluid
Balance.
It is extremely important to monitor fluid balance during this
period of fluid replacement. Patients that have Diabetes Mellitus
often suffer from renal problems concurrently, caused by their
condition (Hardman and Young 2001). Therefore it is important not
to over-load the patient with fluid as it may result in pulmonary
oedema. Renal impairment may have actually been caused by the
severe dehydration they have suffered. This possibility can be
checked, through acarefully kept fluid balance and regular
biochemichal reports. There is a need to ascultate the lungs
regularly for crackling, and monitor the patients oxygen
saturation levels. If any pulmonary oedema is suspected this must
be brought to the attention of the medical staff immediately
(Hardman and Young 2001, Konick-McMahan 1999).
- Insulin
Therapy
.
This should not be initiated until fluid replacement has begun.
There seems to be a general agreement within the literature that
insulin therapy should be administered at low doses through a
continuous intravenous infusion pump (Kitabchi et al 2001,
Chiasson 2003, Jerreat 1999). This way of administering insulin
makes it less likely that the patient will become hypoglycaemic
and hypokalemic by producing a slow and steady drop in blood
glucose levels. It is also thought that a too rapid correction of
insulin and hydration levels can induce cerebral oedema in a few
rare cases. This usually only happens in around 1% of children
with DKA. However, it is associated with a 70% mortality rate so
it is something that health professionals should be aware of (Kitabchi
et al 2001). Regular blood glucose monitoring needs to take place
when the individual commences on insulin therapy. Capillary
measurements should be taken hourly to allow for the adjustment of
insulin dose until the measurements have stabilised (Chiasson
2003). Some blood should also be sent to the lab to check the
efficacy of the capillary blood measurements at least once a day
until the condition resolves.
- Electrolyte
monitoring.
Electrolyte
levels need to be carefully monitored. As previously mentioned,
potassium levels can drop dramatically when fluid replacement
begins as the serum potassium moves back in to the cells. This
occurs usually within the first few hours of treatment (Chiasson
et al. 2003). As this fall can be rapid it is recommended that
replacement therapy begins once the levels fall below 5mmol/L (Chiasson
et al.2003) Potassium infusions should be administered as per
local guidelines and policy. If the levels of serum potassium
begin to fall then the patient should be monitored for arrythmias
and respiratory muscle weakness (Konick-McMahan 1999, Chiasson
2003). Sodium levels should be monitored as a change in the
concentration could result in neurological deficits. The patient’s
level of consciousness should be assessed regularly.
- Bicarbonate
therapy.
This therapy is an alkali therapy for acidosis and there is no
current evidence to support its use in the treatment of DKA. Most
individuals find that their acidosis resolves with fluid
replacement and insulin therapy. However most texts still seem to
recommend its use if the pH is less than 7 (Kitabchi and Wall
1999, Kitabchi et al 2001, Chiasson 2003).
- Patient
care.
Depending on the condition of the patient, care will vary. The
unconscious patient will require full assistance with regard to
the activities of daily living and it essential that privacy and
dignity be maintained wherever possible. Vital signs should be
monitored at least every half an hour for the first hour and then
hourly for the next four hours. They can then be measured every2-4
hours until the condition resolves. It is important to be aware of
temperature fluctuations that may indicate an underlying infection
as the precipitating cause of the event.
- Patient
education.
Education will need to be tailored to the patient depending on the
cause of there DKA or HHNS .If infection was the cause then the
education may need to be provided by a diabetes specialist nurse.
Patients need to be aware of how to manage their condition during
illness and most specialist nurses have a set of ‘sick day rules’
that they provide. (See page regarding diabetes and illness). If
the patient has presented with this condition with no previous
diagnosis of diabetes then they will require a large amount of
input. Again the diabetes specialist nurse may need to be
contacted for lifestyle advice such as: information on drug
therapy; giving up smoking; advice on exercise; advice on
injection technique; site rotation; foot and eye care to name but
a few. It is likely that such intense information giving will need
to take place over a few sessions and may well be completed in the
community. It is the job of the nurse on the ward or unit to back
up and reiterate the information when ever the patient needs extra
support. The patient will also need to be referred to a dietician
for information on diet.
For
those with problems managing their condition health education
consists of reinforcing the information that they have already
been given. It may be worth while referring the patient to the
diabetes nurses in order to discover what might be causing their
uncontrolled blood glucose levels. The patient could be on the
wrong drug or dosage, may have trouble with injection technique or
site rotation. The reason needs to be established why the patient
suffered from either DKA or HHNS so that a recurrence of the
situation does not present itself. Those with psychological
problems they may require the support of the mental health team.
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