OAA Small Project Grant
Is shivering following neuraxial blockade in obstetric patients related to changes in patient temperature? A prospective observational study.
Dr Surbhi Malhotra
Background
Neuraxial blockade is a common method of providing pain relief for labour and anaesthesia for caesarean sections. It involves placing local anaesthetic and other pain killing medications around the nerves in the spine and includes epidural, spinal and combined spinal epidural techniques.
Approximately one third of expectant mothers will undergo a form of neuraxial blockade during the birth of their child. Of these women, up to 70% will experience the side effect of uncontrollable shivering, which many find very unpleasant. Shivering also increases maternal metabolic rate and may have detrimental effects on the unborn child. Currently it is unclear why shivering occurs in this situation. It has been suggested that it is not related to changes in body temperature, but this remains to be proven.
Aims
This study aims to describe the changes that occur in the body's internal and skin temperatures following neuraxial blockade in the obstetric population. Furthermore we aim to find out if shivering in this situation is caused by changes in internal or skin temperature.
Methodology
This is a single centre prospective observational study of obstetric patients undergoing neuraxial blockade for pain relief in labour or anaesthesia for caesarean sections. Patients will have their internal and skin temperatures monitored before and after the administration of neuraxial blockade. We will also measure skin blood flow to monitor vasoconstriction and the electrical activity of muscles to assess shivering. All the sensors, with the exception of the internal temperature sensor, are non-invasive and stick on the skin surface. The internal temperature sensor is an electronic thermometer which will be placed intermittently under the tongue. The data collected will be used to describe internal and skin temperature changes that occur following the administration of neuraxial blockade and to assess the relationship between these temperature changes and the onset of shivering.
Expected outcomes
We expect to find that shivering following neuraxial blockade in the obstetric population is not initiated by changes in internal temperature. We believe that skin temperature will increase in the areas affected by the neuraxial blockade (legs and trunk) and will decrease in the areas unaffected (arms).
Implications
This study will help us understand the mechanism of shivering following neuraxial blockade in the obstetric population. We believe that understanding this mechanism is an important first step towards developing effective treatments for this distressing and potentially harmful side effect.
