Introduction
Two studies compared the effectiveness of i.v. fluids for the treatment of women with HG.69,108 One trial by Tan and colleagues108 tested different compositions of i.v. solution (dextrose plus saline vs. saline only)108 and was judged as low risk of bias. The other study compared the use of diazepam against i.v. fluids containing vitamins69 but was judged as carrying an unclear risk of bias due to lack of sufficient information in a number of areas. Both papers described the trial participants as suffering from HG; however, we classified severity as either moderate,69 or moderate to severe108 based on the participant data provided. As previously described (see Chapter 3, Meta-analysis of included randomised controlled trials), given the differences between trials in patient populations, settings, interventions and, in particular, the heterogeneous nature of the reported outcomes across trials, we did not attempt to perform meta-analyses and have thus reported a narrative summary only for each intervention and comparator set. A summary of study conduct and results is depicted in , with safety data reported in Appendix 8.
Results for i.v. fluid interventions for NVP and HG
Dextrose saline versus saline only
Combined severity score
No combined score reported.
Nausea outcomes
The 10-point VAS was used by Tan and colleagues108 to assess nausea in their trial comparing dextrose plus saline versus saline only i.v. fluids. Although the difference after 24 hours between groups was not found to be significant [dextrose plus saline, VAS score = 2 (SD 1–4), saline only, VAS score = 2 (SD 2–4); p = 0.39], repeated-measures of the analysis of variance for nausea scores detected a significantly greater reduction in favour of the dextrose plus saline preparation (p = 0.046).
Vomiting outcomes
Tan and colleagues108 measured number of episodes of emesis to assess vomiting outcomes and did not detect a difference in the median change in episodes between groups [both groups = 0 (IQR 0–2); p = 0.66].
Retching outcomes
No independent retching scores reported.
Safety outcomes
Tan and colleagues108 did not report any pregnancy outcomes or side effects. No specific UKTIS data were available on this intervention.
Intravenous fluids versus intravenous fluids plus diazepam
Combined severity score
No combined score presented.
Nausea outcomes
For patients with a nausea score of 4+ (classed by the authors as severe nausea), significant reductions for both groups were found on the second and third days of therapy using the VAS (p < 0.05) in the trial of Ditto and colleagues69 They reported that on day 2, this reduction was significantly greater in the diazepam group (p < 0.002); however, post treatment, the difference between groups was not significant (no p-value reported).
Vomiting outcomes
Ditto and colleagues69 assessed vomiting outcomes via number of vomiting episodes. No significant difference between groups was observed (exact p-value not provided).
Retching outcomes
No independent retching outcomes reported.
Safety outcomes
No side effects were reported in the trial of Ditto and colleagues,69 and no statistically significant differences were reported in terms of gestation at delivery; preterm delivery; caesarean section rate; mean birthweight or neonatal abnormalities (p-value not reported). As above, no specific UKTIS data were available on this intervention.
Summary
The evidence available for i.v. fluids was at low
108 or unclear
69 risk of bias.
i.v. fluid improves reported symptoms. Dextrose saline may be more effective at improving nausea over time for those with moderate nausea.
Diazepam appears to be more effective than i.v. fluids alone at reducing nausea on day 2 but there was no evidence post treatment for those with moderate/severe nausea.
Overall, i.v. fluids help correct dehydration and improve symptoms, dextrose saline may be more effective at reducing nausea than normal saline. (The lower concentration of sodium in dextrose saline may exacerbate any pre-existing hyponatraemia. High doses/concentrations of dextrose solutions may increase the risk of Wernicke’s encephalopathy, but concentrations in dextrose saline are unlikely to provoke this response.)
Future studies are required which focus on interventions given alongside rehydration therapy.
