Postpartum chills phenomenon: is it a feto-maternal transfusion reaction?

Non-pharmacological treatments for shivering post neuraxial anaesthesia for caesarean section: a scoping review

BACKGROUND

Shivering occurs more frequently for women having caesarean section under neuraxial anaesthesia compared to other patient groups and causes an increase in pain and interrupts bonding with her newborn.

AIM

This study aimed to report the evidence on non-pharmacological methods to treat shivering, defined as uncontrollable shaking, because of being cold, frightened, or excited, post neuraxial anaesthesia; the use of local anaesthesia inserted around the nerves of the central nervous system such as spinal anaesthesia and epidural in women having a caesarean section.

METHODS

A scoping review was conducted using six electronic health databases that were searched with no restrictions placed on language, date, or study type.

FINDINGS

Of the 1399 studies identified, following screenings only one study was deemed suitable for inclusion. The study, a randomised controlled trial, compared forced air warming blankets (intervention) with the usual care of warmed cotton blankets (control) and its impact on maternal and newborn outcomes. The only statistically significant difference found was the perceived thermal comfort of the mother.

DISCUSSION

Non-pharmacological treatments for shivering are underrepresented in the literature; only one study identified where the impact of active warming was compared to warmed cotton blankets (usual care) for the measures of: oral temperature; degree of shivering; and thermal comfort pain scores. There was a decline in temperature in both groups at odds with some women reporting feeling too warm such that they asked for the active warmer to be turned down.

CONCLUSION

Social engagement strategies are interventions that send a signal of safety to the nervous system leading to a sense of calm and wellbeing and have biological plausibility and warrant evaluation. Recommendations for further research: design a robust study to test the effectiveness of social engagement strategies on shivering for women having caesarean section under neuraxial anaesthesia.

Efficiency and safety of ondansetron in preventing postanaesthesia shivering

Introduction Shivering is one of the most frequent complications of operation during the postanaesthesia period. Ondansetron has been proved to be valid in preventing postanaesthesia shivering (PAS) in several studies. However, its efficiency and safety are still disputable. We therefore performed an updated meta-analysis of randomised controlled trials (RCTs) for evaluation and to clarify this issue. Methods A literature search using the PubMed, Embase™ and Cochrane Library databases was performed (from inception to January 2015). RCTs that evaluated the efficiency and safety of ondansetron in the prevention of PAS were included in the meta-analysis. The primary outcome measure was incidence of PAS, and secondary outcomes included subgroup analysis and the side effects of ondansetron. Results A total of 8 RCTs containing 905 subjects were identified as suitable for this review. Compared with placebo, ondansetron was associated with a significant reduction of PAS (relative risk [RR]: 0.33, 95% confidence interval [CI]: 0.19-0.58, p=0.0001) while no difference was detected between ondansetron and pethidine (RR: 0.89, 95% CI: 0.41-1.94, p=0.78). There was no significant difference between ondansetron and placebo or pethidine in terms of risk of bradycardia but ondansetron was associated with a lower risk of hypotension (RR: 0.26, 95% CI: 0.08-0.79, p=0.020) than placebo. There was no difference in hypotension when ondansetron was compared with pethidine. Conclusions Ondansetron can prevent PAS effectively and reduce the risk of hypotension.

Complement, fetal antigen, and shaking rigors in parturients

OBJECTIVES

To assess the relationship, if any, between complement, fetal antigen, and shaking rigors during labor and delivery.

METHODS

We recruited 13 volunteers for serial blood sampling during labor and childbirth.

RESULTS

Complement levels had a small but significant drop (11-15%) immediately following childbirth but had no association with fetal antigen levels or shaking rigors. Fetal antigen levels failed to show any consistent relationship with shaking rigors or the labor and delivery process.

CONCLUSION

Shaking rigors do not appear to be associated with changes in either complement or fetal antigen levels. Complement levels remain stable during labor but drop immediately following birth.

Risk factors for fetal-to-maternal transfusion in Rh D-negative women--results of a prospective study on 942 pregnant women

AIMS

To investigate the incidence of severe fetal-to-maternal transfusion after delivery and to identify risk factors.

MATERIAL AND METHODS

In a prospective study at the Department of Obstetrics, Charité, Campus Virchow-Klinikum, Berlin, Germany, we analyzed the incidence of severe fetal-to-maternal transfusion (>10 ml) and fetal-to-maternal hemorrhage (>25 ml) in Rh D-negative pregnant women after delivery of Rh D-positive infants. 942 women were included in the study and Kleihauer-Betke tests were performed. The results were compared to perinatal data.

RESULTS

Fetal-to-maternal hemorrhage occurred in 13 cases out of 942 (incidence of 1.3%) and severe fetal-to-maternal transfusion in 61 cases (6.5%). In all of the cases with fetal-to-maternal hemorrhage, mothers were compatible with their infants in ABO-system. The incidence of fetal-to-maternal transfusion and its severe form was significantly higher in twin pregnancies (7/21 cases and 5/21 cases respectively, 33.3% and 23.8%) than in singleton pregnancies (22.5%, and 5.9%, P<0.001). All other factors, such as maternal age, parity, ethnicity, mode of delivery, presentation, duration of first and second stage of labor, CTG, or Apgar score were not associated with an increased risk of severe fetal-to-maternal transfusion.

CONCLUSIONS

Twin pregnancy is the only independent risk factor for severe fetal-to-maternal transfusion. ABO-incompatibility between mother and infant seems to be protective against Rh D-alloimmunization.