16.2 Testing Block C Section Flashcards
a) Which dermatomes should be blocked
prior to an elective caesarean section (CS)
and how may the
adequacy of the block be tested? (30%)
There is a lack of consensus on dermatome level that the upper extent of block should reach in the different testing modalities.
The levels written here are commonly, but not universally, accepted.
> > Upper level T4 bilaterally to cold:
with ethyl chloride spray, demonstrate
sensation on unblocked skin.
Then spray on blocked skin moving in a
cephalad direction until cold sensation perceived.
Repeat on contralateral side.
> > Upper level T5 bilaterally to light touch
(when intrathecal opioid is given):
testing as above with cotton wool or
touch of spray on skin.
> > Upper level T5 bilaterally to pain:
testing as above with Neurotip.*
> > Lower level S5 bilaterally:
check the lower extent of block
to cold or light touch –
can check S2 at sole of foot.
Lack of awareness of urinary catheter insertion indicates loss of touch sensation at sacral level.
> > Motor block: Bromage 3 (unable to flex knees) or 4 (unable to move legs
or feet) is required.
b) How might an initially inadequate block be improved sufficiently to allow surgery to proceed? (30%)
> > Positioning:
flex hips to flatten lumbar lordosis,
cautious head down tilt
or lateral tilt if block inadequate
on one side
(remember need to avoid
aortocaval compression).
> > Epidural: if using epidural or
combined spinal and epidural,
top up the epidural.
If using spinal only,
consider inserting an epidural in order to
raise the height of the block.
> > Repeat spinal:
consider reducing overall dose
if some block is present.
Good attention to patient positioning
should help prevent high spinal.
c) How could you manage a patient who complains of pain during a spinal CS? (40%)
Communication:
» Ask obstetricians to stop surgery
whilst establishing pain control
(depends on stage of surgery –
not feasible after uterine incision and
before delivery of baby).
> > Ask obstetricians to handle tissues
as carefully as possible, avoid
exteriorisation of uterus,
large paracolic gutter packs etc.
> > Ask the woman to describe the sensations felt. Determine whether it is true sharp pain
or the normal tugging sensations
that are to be expected.
Reassurance often helps, but even
if they are the ‘normal sensations’,
if the woman remains distressed,
then it should be addressed in the same
manner as ‘true’ pain.
_____________________________
Options for pain relief:
» If surgeons have only just started
skin incision, consider covering the
wound, turning patient on their side,
repeating spinal.
> > Entonox.
> > Alfentanil 50 mcg aliquots intravenously.
Give oxygen, request the
presence of paediatrician if before delivery,
and inform them that opioids
have been given.
Morphine may then be given after delivery.
> > Ketamine 5–10 mg boluses if familiar with its use.
> > Local anaesthetic infiltration by surgeons if baby delivered and starting to close.
> > General anaesthetic must be offered regardless of stage of surgery if the
woman remains uncomfortable.
Postoperatively:
» Documentation of woman’s experiences,
stage of surgery and action undertaken.
Include offers of options that
the woman may have declined.
> > Ensure adequate postoperative
analgesia if the block has failed –
sufficient opioids,
transverse abdominis plane blocks.
> > Debrief with the woman postoperatively
once pain is controlled,
after returning to ward,
consultant involvement if necessary.
Offer anaesthetic
clinic appointment after discharge if the
patient would like further conversations.
b) Describe the actions you could
take if your spinal block proves
inadequate on testing prior to
starting surgery for an elective
(category 4) caesarean section.
(3 marks)
> > Improve current block if close to adequate block on assessment:
• Positioning; flex hips to flatten the lumbar lordosis,
cautious head down tilt,
tilt to suboptimal side
(remember need to avoid aortocaval compression).
• Ensure that adequate time has been allowed for block development.
> > Further regional technique:
• Repeat spinal –
consider reducing overall dose if some block is present,
good attention to patient positioning to help prevent high spinal.
• Epidural –
height of spinal block may be elevated by epidural injection,
epidural component itself also provides anaesthesia.
> > General anaesthetic:
• If the patient does not want to consider further regional technique and
there are no compelling contraindications to this.
c) What are the early symptoms
and signs of a spinal block that is
ascending too high? (5 marks)
Symptoms:
» Difficulty breathing or taking a deep breath,
difficulty speaking.
> > Nausea and vomiting.
> > Anxiety, feeling faint.
> > Tingling and weakness of hands
and arms.
Signs:
» Decreased respiratory effort,
reduced saturations, weak cough.
> > Cardiovascular instability:
bradycardia and hypotension.
> > Objective weakness of hands
then arms then shoulders,
high block on retesting.
> > Sedation.
