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SPECIMEN
SPINAL TECHNIQUE FOR ELECTIVE CAESAREAN SECTION
| 1 |
Preload
the patient with 500–1000 ml of normal saline
or Hartmann’s solution. |
| 2 |
Perform
a lumbar puncture in the lateral or sitting position.
Use strict asepsis. To prevent post-spinal technique
headaches, always use a fine gauge spinal needle: 25
or 27 gauge. |
| 3 |
Inject
about 1.5–2ml of 5% “heavy” lidocaine
or 2 ml bupivacaine with the patient in the lateral
position
| • |
Heavy
lidocaine 5% with 7.5% dextrose is commonly used,
as it is inexpensive; unfortunately, it lasts
only 45–60 minutes, so the surgeon should
be experienced and the caesarean section a straightforward
one without adhesions |
| • |
Where
available, 0.5% isobaric or hyperbaric bupivacaine
is preferable to lidocaine. |
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| 4 |
Immediately
after injecting the spinal dose of drug, turn the mother
into the horizontal position, but with the pelvis wedged
so that the gravid uterus leans substantially to the
left side. Make sure the mother’s position is
secure and that she cannot fall. |
| 5 |
Be
extra vigilant, and actively treat any fall in systolic
blood pressure to below 90 mmHg (12.0 kPa). Hypotension
can harm both fetus and mother. Initial treatment of
hypotension is to give up to 1000 ml of colloid or crystalloid
solution rapidly, within 5 minutes or less. |
| 6 |
If
the pressure remains low, give:
| • |
Vasoconstrictor,
such as ephedrine, in 5–10 mg increments |
| • |
Consider
using a continuous ephedrine infusion: 30 mg
in 500 ml |
| • |
If
this is not available, give a diluted solution
of 0.5 mg adrenaline diluted in 20 ml normal
saline intravenously, 1 ml at a time; this is effective,
though rather abrupt in onset and offset. |
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| 7 |
Always
give oxygen to the mother during the operation. |
The
ideal height of block is between the xiphisternum (T5/6) and
nipple line (T4). Remember that in pregnant women at term, the
block very easily goes high. Give a dose reduced by 0.5 ml compared
with the dose you would give to a non-pregnant woman of the same
size. For example:
| :: |
Small woman: 1.2 ml heavy lidocaine |
| :: |
Medium height woman: 1.5 ml heavy lidocaine |
| :: |
Large woman: 2 ml heavy lidocaine.
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If
using isobaric (non-glucose containing) solutions, increase
the dose by 0.5 ml. For example, a small woman having a first
time caesarean section, with easy surgery and short duration
of operation expected, would receive
1.2 ml heavy lidocaine. A large woman having her third
caesarean section would be better given 2.5 ml of isobaric
bupivacaine because obesity and adhesions will mean a longer
operation.
Bupivacaine appears to require 0.5 ml more than lidocaine.
Plain lidocaine 2% can be used, but the block is not so good and
2.5 ml will be needed in a
mother where 1.5 ml of 5% lidocaine would have been used.
If surgery is prolonged and the patient starts to feel
pain, give IV analgesics such as opiates or low dose ketamine.
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