Continues...
Gradually I settled into the routines of night shifts. Uncluttered by the day throng of visitors, scheduled procedures, phone calls and the daily round of dramas, nurses on night shift had more time to focus on the routine needs of their patient. They were not as distracted by the demands of visiting specialists, ancillary staff such as dieticians, radiographers, speech pathologists and other itinerant floaters.
I came to know
the nurses better at night. I heard of their
experiences, ambitions, the rigours of shift work, even their love lives. I demonstrated a few yoga asanas to some to relieve lower back
pain. One dedicated soul asked me if
there were yoga manipulations that
could help the inner workings of unconscious patients. I showed her a couple of gentle twists that
would greatly relieve wind discomfort.
The nurses' work is physically and mentally demanding – adjusting
patients, lifting equipment, constantly on their feet, concentrating for twelve
hours while attending to the minutiae surrounding equipment sterilization,
fluid sampling, patient monitoring, drug and nutrition maintenance, patient
hygiene and general care, bed cleaning and sundry other tasks. They were always cheerful, sympathetic and
caring. They shooed wolves of woe away
from my door many times. I would have
despaired without this extraordinary group of men and women.
As
the days rolled on nasty side effects became manifest. The most accurate
measure of arterial blood pressure (BP) involved puncturing the artery with a
micro-puncture needle or a catheter-over-needle cannula assembly.
After
the second craniotomy, maintenance of an accurate arterial signal became
problematic. Carolie’s arteries seemed
formless as fluid swamped her metabolism. I will not attempt an exposition of
the technical complexities underlying this problem. Suffice to mention maintenance of the line
frustrated many.
To begin with, I had to
leave whenever a registrar and nurse took on the task of line replacement. The more familiar I became with ICU processes,
the more confident the staff became in my ability not to wilt. I was part of
the furniture, witnessing radial artery cannula replacement several times. The
meticulous attention to sterilization and preparation was fascinating. I was relatively sanguine about the process,
until Carolie’s arterial stability sharply deteriorated.
On
several occasions, I watched registrars ‘farm’ her illusive arteries
unsuccessfully for hours, trying to secure the line assembly. A senior registrar laboured for several hours
and got nowhere - his was the last attempt.
It was terrible to watch. He
tried several sites in both arms and then made a final sortie in the femoral
artery located in the groin. His failure
left him a little perturbed, declaring he had never seen anything like it
before.
Non-invasive but less accurate
methods of monitoring BP sufficed from this point. Again, Carolie’s response to treatment had
taken a mysterious path and baffled her treatment team.
Close
monitoring of BP is a critical diagnostic tool in treatment of SAH
patients. The pressure must not fall too
low as this has implications for blood circulation and vasospasm, nor must it
go too high, as this is equally dangerous.
Carolie’s was often up and down.
She frequently turned febrile, which meant more analgesics.
The team discovered 1000mg of paracetamol
sent her BP plummeting. She was an
extremely rare example of the phenomenon.
Catch 22: not enough paracetamol
– slow reduction of body temperature; too much paracetamol – rapid drops in
BP. I had parroted her susceptibility to
drugs to anyone who would listen, now writ large in this fine balancing
act.
The
external ventricular drain or EVD revealed another nasty conundrum. Wikipedia
explains
EVD is a device used in neurosurgery to relieve raised
intracranial pressure and hydrocephalus when the normal flow of cerebrospinal
fluid (CSF) around the brain is obstructed. This is a plastic tube placed by
neurosurgeons and managed by ICU nurses … to drain fluid from the ventricles of
the brain, and thus keep them decompressed, as well as to monitor intracranial
pressure.
I
discovered the cranial vault is similar to a rigid box. The volume of the three
components within the skull (brain matter, blood and CSF) must remain
equal. To avoid a spike in ICP an
increase in one component is offset by a decrease in another. The juggling act is fraught with danger. In Carolie’s case, a closed sterile system
allowed drainage of CSF via a silastic catheter tip that rested in the anterior
horn of her lateral ventricle.
The
system enabled nurses to check the rate of flow and conduct sterile CSF
sampling. As any foreign object such as a tube in the brain presents a
high-risk source of infection, nurses observe strict protocols. Pathologists tested the extracted fluid for
blood culture analysis. The EVD was an essential part of managing ICP but it
presented major risks – drain insertion damaged brain tissue and its ongoing
presence threatened infection.
Forewarned
is not forearmed. Early in March Carolie became febrile with ventriculitis,
caused by a bacterial infection.*
The
EVD from Carolie’s first night in the labyrinth came out and a high dosage of
antibiotic was commenced. After a
further CT scan revealed ongoing cerebrospinal fluid problems the surgeons
inserted a new EVD, ceased the antibiotic just over a week later and warned me
of the unavoidable but acceptable risk of further brain tissue damage from the
procedure - ‘acceptable’ because of the
higher risks associated with uncontrolled ICP.
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