I
spent long hours with Carolie over the next days, becoming familiar with the
rhythms of ICU care and post-operative procedures. The main concern after clipping is vasospasm*, a temporary narrowing of the arteries,
which is an acute risk during the post-operative period. She was receiving a suite of drugs
intravenously, including Verapamil and Nimodopine to manage hypertension and
vasospasm.
Various actors told me many
things about this condition but I heard it through a fog. CT scans and angiograms¥ became routine - my only role was to provide
written permission for each procedure.
Carolie was responding to commands and occasionally would acknowledge
visitors with a thumb up.
Several
days after her initial surgery I felt confident enough to rush home to Canberra
for a day and a night to sort out the minutiae of life and get our cat stowed
with friends. Little could this couple
know how the stowage period would blow out! Having access to my computer, I updated as
many people as possible. One of my
messages went like this:
Sometimes life hits you like a
thunderbolt, and things taken for granted seem like the most precious
gift. Carolie operated on
successfully. She is stable and
responding to commands. She remains on
life support and we are hopeful improvements will continue. It is a devastating shock for family, friends
and colleagues, all of whom focus on her recovery… She is stable after the aneurysm clip procedure, and CT scans are
favourable so far. She is having regular angiograms and all sorts of
regimes. It is all impressive.
I
returned to Sydney the next day to resume my vigil.
During
the night, six days after the craniotomy, Carolie had an asystolic arrest, a
major setback involving a spike in ICP and a rapid deterioration of blood
pressure. They clamped her brain fluid drain (EVD) and transferred her
for urgent CT scan. During the scan, she
experienced Cushing’s response, one of several terms used to describe this
acute life-threatening event.+ Her heart stopped for less than 30
seconds. Doctors applied twenty
compressions to her heart area and injected a drug called Mannitol; a diuretic
agent extracted from plants and used clinically to reduce acutely raised
ICP. She had almost died a second time.
These
frightening turn of events saw Carolie put in a chemically induced coma utilizing a barbiturate called Sodium Thiopental. Wikipedia tells us the drug is usually the
first of three drugs administered during lethal injections in the United States
and used intravenously for the purposes of euthanasia. Not much comfort there but it goes on:
Patients with brain swelling, causing elevation of the
intracranial pressure, either secondary to trauma or following surgery, may
benefit from this drug. Sodium thiopental, and the barbiturate class of drugs,
decrease neuronal activity and therefore decrease the production of osmotically
active metabolites, which in turn decreases swelling. Patients with significant
swelling have improved outcomes following the induction of coma. Reportedly,
thiopental has been shown to be superior to pentobarbital in reducing
intracranial pressure.
This
was not a particularly sophisticated drug, except of course if you wanted to
use it as a truth serum, as in many Hollywood films. It was the barbiturate equivalent of a depth
charge, with similar targeting problems.
It could wear off in days but it was far from an exact science. To complicate matters the neurosurgeons had
no idea whether the ‘arrest’ had wrought additional brain damage.
Disturbingly,
I did not know this had happened on the night.
Under ICU protocols, contact with next of kin should occur as soon as
practicable but in all the excitement it fell through the cracks. Blissfully unaware that my beloved wife had
almost died and that untold additional damage might have occurred, I waited
outside the ICU on arrival the next morning.
There was clearly something wrong
as usually I had immediate access. As I
battled creeping alarm, one of the neurosurgical team rang me to explain the
night’s events. Darkness descended. All of the encouraging signs of the last few
days had evaporated - the pool of tears was deepening.
To be continued...
*
An aneurysm is a fluid-filled sac
in the wall of an artery that can weaken the wall (see p.16). The presence of blood in the fluid around
these arteries can cause temporary narrowing (or vasospasm) to develop in the
arteries. Vasospasm usually happens somewhere between 5-10 days after the
initial blood loss from the burst aneurysm.
When the arteries become narrowed due to vasospasm, there may be a
decrease in the flow of blood to the parts of the brain supplied by arteries
affected by the narrowing
¥ Interventional
radiology is minimally invasive and uses X-ray or ultrasound images to guide
procedures, usually done with tiny instruments through small plastic tubes
called catheters inserted through an artery or vein. Specialist doctors called
interventional or neurointerventional radiologists, or neurosurgeons or
neurologists, perform these procedures. SAH Vasospasm Endovascular Treatment is
performed in an angiography suite (or room) of a hospital, which looks like an
operating theatre. Angiography is the X-ray examination of blood vessels after
a dye (or contrast medium) is injected into the bloodstream that shows up on
live X-ray pictures or images used to diagnose any abnormalities.
+ Cushing’s response (also referred to as the vasopressor response, the Cushing
effect, the Cushing reaction,
the Cushing phenomenon, or Cushing's Law) is a physiological
nervous system response to increased intracranial pressure (ICP) that results
in Cushing’s triad of widening pulse pressure, irregular breathing, and a
reduction of the heart rate.
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