Lidocaine and Ketamine Levels in Plasma After Simultaneous Lidocaine/Ketamine Infusions

Lidocaine and Ketamine Levels in Plasma After Simultaneous Lidocaine/Ketamine Infusions. An Observational Assessment of Therapy Effects and Side-effects.

The aim of this monocentric observational pilot study is to measure the lidocaine plasma level in a limited number of patients to generate explorative data on inter- and intrapersonal stability and safety of drug plasma levels and to investigate whether higher plasma levels of ketamine can be correlated with a better analgesic effect.

There are different treatment strategies for chronic pain. One possible treatment strategy, especially for therapy-resistant pain, is intravenous infusions with certain pharmacological agents, such as lidocaine and ketamine. This study is to measure the concentration of lidocaine in the plasma of patients at the University Hospital of Basel (USB) after an intravenous infusion with 4mg/kg lidocaine over 30 minutes in order to generate explorative data on inter- and intrapersonal stability and safety of drug plasma levels. The prospective side effects of lidocaine and ketamine is assessed and the plasma levels are correlated with the analgesic efficacy and change in possible depressive symptoms.

Inclusion Criteria:

• Patient is a new recipient of lidocaine-ketamine infusions
• Patient is able to provide Informed Consent

Exclusion Criteria:

• Contraindication to blood sampling (on arm not used for infusion)
• Insufficient knowledge of German language
• Inability to give consent
• Patient is under 18 years of age
• Contraindication to treatment with lidocaine and/or ketamine