Autonomic changes during cancer chemotherapy induced nausea and emesis.

Certain autonomic variables have been shown to be responsive to motion induced nausea and vomiting. Here we report preliminary data on changes in heart rate, blood volume pulse, pallor and skin temperature assessed during a one hour period at baseline, a one hour period of peak nausea, and a one hour period of emesis in five female patients receiving identical cancer chemotherapy and antiemetic drugs according to a common protocol. Examination of coefficients of variation showed that heart rate and face temperature were more stable measures across each of the three time periods than blood volume pulse and pallor. Furthermore, the four measures were found to be more variable during times of emesis than times of nausea. The four measures were shown to be responsive to patient reported nausea and vomiting. Temperature and pallor showed a linear change from baseline to nausea to vomiting. Heart rate and blood volume pulse significantly decreased from baseline time during nausea and then significantly increased from a time of nausea to during emesis. Variations in the time course of each variable change during nausea supported a view that nausea may be more related to a rebound of parasympathetic activity than a slow decrease of sympathetic activity. Replication with larger samples is needed. Examination of the nausea and vomiting of pregnancy, general anaesthesia or different chemotherapeutic agents could help explore whether results reported here are singular or representative of a more generalisable autonomic response associated with patient reported nausea.