BACK GROUND :
Hypotension in Spinal anaesthesia is inevitable. In parturients due to aortocaval
compression, increased sensitivity to local anaesthesia and increased peripheral
venous pooling of blood, hypotension occurs with greater frequency and severity.
Management of spinal hypotension is always a challenge to obstetric anaesthesiologist
because of dual concern of both mother and the foetus. Fluid preloading and coloading
are commonly used but their role in prevention of spinal hypotension is
doubtful. Use of vasopressor for prevention of spinal hypotension is associated with
risk of foetal acidosis. Physical methods like leg compression with elastic crepe
bandage, compression stockings and leg elevation prevents hypotension by
augmenting venous return without affecting foetal outcome.
AIM AND OBJECTIVES :
To evaluate and compare the effectiveness of two simple techniques: leg
elevation and leg wrapping in prevention of spinal hypotension in elective caesarean
section. To compare the incidence of hypotension, vasopressor usage and
haemodynamic changes among the groups.
MATERIALS AND METHODS :
This prospective, double-blinded, and randomized controlled trial was
undertaken after the approval by Institutional Ethical Committee. 90 full term
parturients with singleton uncomplicated pregnancy belonging to American Society of
Anesthesiologist (ASA) Class I or II, scheduled for elective caesarean section under
spinal anesthesia were allocated randomly to either leg wrapping group BLW (n =
30) or leg elevation group BLE (n = 30) or control group BC(n = 30).
Leg wrapping group patients had their lower limbs wrapped just before the
administration of the subarachnoid block with elastic crepe bandage (15 cm width, 4
m stretched length) applied from the ankle to the mid-thigh in both legs. Leg elevation
group patients had their legs elevated immediately after spinal anaesthesia to an angle
of 30° from the horizontal plane. Control group patients had their lower limbs neither
raised nor wrapped.
Baseline heart rate and blood pressure were recorded and intravenous fluid
preloading was done with 20 ml/kg of ringer lactate solution over 15 to 20 minutes
just prior to the spinal anesthesia in all patients. All patients were given spinal
anaesthesia with injection 0.5% hyperbaric bupivacaine in the dosage of 0.06mg/cm.
Thereafter, the patients were placed in supine wedged position. Hypotension was
defined as fall in systolic blood pressure to 90 mmHg or fall more than 20% from
baseline blood pressure and was treated immediately by increasing the rate of ringer
lactate administration and by ephedrine 6mg intravenously. Total dose of ephedrine
used were noted.
STATISTICAL TOOL :
Analysis of variance with post hoc test and chi square test were used to test
the significance. A ‘p’ value of less than 0.05 was taken to denote the statistical
significance.
OBSERVATION AND RESULTS :
The incidence of hypotension in leg wrapped group is 3(10%) patients,
compared to 10 (33.33%) patients in leg elevated group and 15(50 %) patients in
control group. The chi-square score was 4.8118 and ‘P’ value was 0.0282 (< 0.05)
when leg wrapped group was compared with leg elevation group which was
statistically significant. Similarly when leg wrapped group was compared with control
group, the chi-square score was 11.428 and the ‘P’ value was 0.0007, which was also
statistically and clinically significant. But when leg elevation group BLE was
compared with control group BC, the chi-square score was 1.7143 and the ‘p’ value
was 0.190 which was not significant statistically. This implies leg elevation alone did
not reduce the occurrence of hypotension. Total ephedrine usage was 18mg in leg
wrapped group, 78mg in leg elevation group and 162 mg in control group.
Haemodynamic stability was better maintained in leg wrapping group compared to leg
elevation and control groups.
CONCLUSION :
We conclude that leg wrapping with elastic crepe bandage just before
subarachnoid block, significantly decreases the incidence of spinal hypotension and
causes a marked reduction in the usage of vasopressor agents when compared to leg
elevation and control groups. Thus leg wrapping technique eventually results in better
maintenance of uteroplacental circulation and foetal outcome. As leg wrapping with
elastic crepe bandage is cheap, easy, readily available and non-invasive , this
technique can be recommended along with other routinely used methods like left
uterine displacement with wedge for preventing spinal hypotension and for better
maternal and foetal care
