Cardiac output response to a colloid

preload for spinal anaesthesia for

caesarean section in patients with severe

preeclampsia

A Vorster, MJ Arcache, S Schulein, A Emmanuel, D van Dyk, O Okaisabor, AR Reed, MF James, RA Dyer

Introduction

• Fluid management in preeclampsia controversial

– Risk of pulmonary oedema

– Risk of renal injury

• Current restrictive practice appropriate for the patient not invasively monitored

• Individualised fluid therapy is possible when haemodynamic monitoring is available

Aim of study

Measurement of stroke volume

responsiveness in women with severe

early onset preeclampsia undergoing

spinal anaesthesia for caesarean section

Patients and methods

• 42 patients

• Severe treated early onset preeclampsia

• No other cardiovascular disease

• Maternal indication for Caesarean section

• Eligible for spinal anaesthesia

• LiDCOrapid haemodynamic monitor

Prior treatment

• MgSO4

• Antihypertensives

– Dihydrallazine

– Alphamethyldopa

– Nifedipine

• Fluids

– 50-100 mL/ hour IV

– NPO for theatre

In theatre

• 16 G IV line

• 20 G arterial line

• Left lateral position

• LiDCOrapid haemodynamic monitor

• Baseline haemodynamic data

• 300 ml HES 130/0.4 via rapid infusion

• Post infusion haemodynamic data

• Data averaged over 1 minute

Change in Cardiac Output

02

9

31

0

5

10

15

20

25

30

35

< 0% 0 - 5% 5.1 - 10% > 10%

Nu

mb

er

of

pa

tie

nts

Percentage Change

dCO

Change in Stroke Volume

4

15

10

13

0

2

4

6

8

10

12

14

16

< 0% 0 - 5% 5.1 - 10% > 10%

Nu

mb

er

of

pa

tie

nts

Percentage Change

dSV

Change in Heart Rate

6

9

17

10

0

2

4

6

8

10

12

14

16

18

< 0% 0 - 5% 5.1 - 10% > 10%

Nu

mb

er

of

pa

tie

nts

Percentage Change

dHR

Change in Mean Arterial Pressure

5

20

15

2

0

5

10

15

20

25

< 0% 0 - 5% 5.1 - 10% > 10%

Nu

mb

er

of

pa

tie

nts

Percentage Change

dMAP

14.8

7.8 6.94.3

0

5

10

15

20

25

30

dCO dSV dHR dMAP

Pe

rce

nta

ge

Percentage Changes from Baseline

Relation between SV and HR

Conclusions

• Significant cardiac output increase with limited colloid preload:– Mediated by increase in both HR and SV

• A larger study may provide:– Information on correlation between stroke volume

responsiveness and vasopressor requirement

– Clearer guidelines for fluid administration

• Caution in administering further fluid to those who respond with a significant increase in heart rate

Thank you