ACCREDITED CPD - SURGERY
A small curette is gently used to try peel off the
membrane from the underlying bone. The dorsomedial section of the middle ear should be avoided
with the curette as this will damage the structures
of the internal ear. The membrane is usually a grey
black colour, once removed there should be a
shiny white appearance to the bone of the middle
ear (Fig 7).
The surgical site should be irrigated with saline and
the subcutaneous tissues and skin closed. The decision to place a drain is the choice of the surgeon.
However if the ear has had a culture taken as a part
of the work-up, an appropriate course of intra-operative antibiotics is sufficient. This varies from case
to case and the amount of contamination during
the surgery and the surgical time. I generally don’t
place a drain after the surgery.
Figure 4. The vertical ear canal is seen with the initial dissection
performed. The facial nerve is not visible at this point.
The use of postoperative antibiotics is controversial
as if all tissue has been removed and thorough lavage performed there should be no need for continued antibiotics. It would be bad practice to rely
on antibiotics to prevent infection from tissue left
behind. If there is any secretory tissue left behind
regardless of antibiotics used it is likely that the infection will return. A culture can be taken form the
bulla once the secretory lining has been removed
and lavage has been done.
Postoperative care
Pain control is essential in these patients. This
should be titrated on a patient to patient basis. Basic
pain control can be managed with injectable opioids, the pure agonists being the obvious choice.
Generally I will start the patient on morphine every
4 hours at 0.5mg/kg. The next stage would be a
fentanyl CRI. In patients that are still assessed to be
in pain then a morphine, lignocaine and ketamine
infusion is administered. Pain control is continued
as long as is required.
These patients are often hypothermic from the extended surgical time and this complication needs
to be monitored and addressed. The best is to
warm them up with warm air blankets to prevent
thermal burns. I will often use ocular lubricants
post-surgery as there can be a delayed blink reflex
from neuropraxia of the facial nerve. This tends to
return to normal in 24 to 48 hours.
In most cases when there has been no obvious
contamination of the surgical site I will use antibiotics based on a culture for 12 hours post-surgery.
I generally do not continue them longer than this.
Figure 5. The vertical (VEC) and horizontal ear canal (HEC)
have been dissected and the facial nerve can be seen in
close proximity (FN)
Figure 6. The ear canal removed completely.
However if there is obvious evidence of bulla osteomyelitis the antibiotics should be continued on the
basis of a culture for 4-6 weeks.
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