///2009 Abstract Details
2009 Abstract Details2019-08-03T15:55:31-06:00

Preload or Co-load for Spinal Anesthesia for Cesarean section

Abstract Number: 192
Abstract Type: Meta Analysis/Review of the Literature

Renato Stocche MD1 ; A Banerjee FRCA2; S Halpern FRCPC3


Hypotension following spinal anaesthesia for caesarean section is a common complication. The efficacy of pre-induction fluid loading to prevent this complication is controversial.The purpose of this systematic review is to compare pre-induction fluid loading (preloading) to fluid loading at induction(co-loading)in elective caesarean sections.


We sought randomized controlled trials in Medline and Embase (Jan 2004 until Nov 2008) using the following key words and text words with alternate spellings: elective, caesarean section, spinal, preload or co-load.We also searched the bibliographies of relevant reviews and identified RCTs.Finally, we searched for published abstracts from relevant anesthesia meetings from 2000 to 2008 [Full manuscripts were rated for quality using the Jadad(1)Scale and an additional point was given for concealment of randomization].The primary outcome was the incidence of hypotension and the secondary outcomes were the lowest blood pressure recorded, incidence of nausea and vomiting, umbilical arterial pH and vasoconstrictor dose. Data synthesis was done using Mantel-Haensel, Fixed effect, Odds Ratio (OR) + 95% Confidence Interval (CI) for dichotomous outcomes and weighted mean difference (fixed effect) for continuous variables. A statistically significant difference between groups occurred when the 95% CI did not include 1.0.


We found 6 RCT with 432 patients, 3 were abstracts(2-4) and 3 were full manuscripts(5-7). The quality of the 3 was 3,2,and 4 as per Jadad scale.The incidence of hypotension was 61.4% in the preload group and 60.8% in the co-load group (OR= 1.19, 95% CI 0.76 to 1.91).There was no difference in any of the secondary outcomes (Table 1).


There was no difference in the incidence of hypotension or in any of the other secondary outcomes measured in these studies.These studies suggest that a fluid bolus, given before spinal anesthesia for elective cesarean section may not be necessary.

Table 1

Outcome Number of studies Number of Participants Weighted Mean Difference + 95%CI or Odds Ratio P-value

Lowest BP 4 322 WMD = -1.08 [-3.54, 1.37] 0.39

Incidence of nausea and/or vomiting 4 336 OR = 1.16 [0.70, 1.91] 0.57

Umblical artery pH 4 312 WMD = -0.00 [-0.02, 0.01] 0.55

Vasoconstrictor dose 5 372 WMD = -0.39 [-0.84, 0.06] 0.09


1. Control Clin Trials 1996; 17:1-12

2. Anesthesiology 2004; 100, Supp 1

3. ASA 2008, A1128

4. ESA 2006; 23, Suppl 37 A 685

5. Anaesth Intensive Care 2004; 32: 351-357

6. Rev Bras Anestesiol 2004; 54(1): 13-19

7. Journal of Clin Monit and Computing 2007; 21: 125-129

SOAP 2009