Target-Controlled Infusion in the US
Target-controlled infusion aims to infuse IV drugs to a set concentration that is specific to a patient’s physiology. Generally, IV drugs are given according to dosing guidelines and can be weight-based. Other factor such as age, sex, and creatinine clearance are often not considered when dosing IV anesthetics, but they may affect how IV drugs are taken up and metabolized by the patient (Struys et al., 2016). This technology is used to administer medications that are tailored to a patient’s needs and to adapt to the many physiological changes that occur during surgery. However, barriers remain to the adoption of target-controlled infusion in the US.
Continuous infusions set a specific drug administration rate. In TCI systems, there is a target concentration that the anesthesiologist will set the infusion to. The goal is to achieve a specific drug concentration in a user-specific manner. While anesthesiologists are unable to measure drug concentrations in the tissue as they are being infused, they use pharmacokinetic and pharmacodynamic models to estimate concentrations and change titration based on those measures. Examples of medications used with TCI pumps include fentanyl, alfentanil, sufentanil, midazolam, and propofol (Struys et al., 2016).
Target-controlled infusion systems are widely used in other parts of the world, particularly in Europe. However, the adoption of target-controlled infusion systems in the US has been much slower. This is largely related to regulatory concerns rather than safety issues. In fact, now that this technology has been used globally for almost 3 decades, data generally shows that it is similarly as safe as anesthetic administrations with constant rate infusions (Schnider et al., 2016). Though it has potential advantages, TCI has not yet been approved by the US Food and Drug Administration for general use. The FDA requires that the device must be safe and reliable prior to being used. Manufacturers must prove that the pharmacokinetic models of TCIs are accurate and safe across diverse patient populations (Dryden, 2016). To receive approval in the United States, different regulatory pathways may be taken depending on which types of models, pumps, and anesthetic drugs are used (Schnider et al., 2016).
Ultimately, target-controlled infusion is a promising advancement in the delivery of anesthetic drugs, offering the potential to increase precision, safety, and efficiency. While the adoption of target-controlled infusion in the US lags compared to other countries, it is not without reason. As with any new advancements or technological changes, TCI must be proven to prioritize patient care and safety. Other areas for advancement include incorporating real-time reporting from the device to anesthesiologists as well as improving communication between target-controlled infusion systems and other medical devices in use in the hospital. Ongoing research and technological advancements may pave the way for TCI to become a standard of care.
References
Dryden, Paul E. “Target-Controlled Infusions: Paths to Approval.” Anesthesia and analgesia vol. 122,1 (2016): 86-9. doi:10.1213/ANE.0000000000001018
Schnider, Thomas W et al. “The Safety of Target-Controlled Infusions.” Anesthesia and analgesia vol. 122,1 (2016): 79-85. doi:10.1213/ANE.0000000000001005
Bidkar, Prasanna Udupi et al. “Target-controlled infusion – Past, present, and future.” Journal of anaesthesiology, clinical pharmacology vol. 40,3 (2024): 371-380. doi:10.4103/joacp.joacp_64_23
Struys, Michel M R F et al. “The History of Target-Controlled Infusion.” Anesthesia and analgesia vol. 122,1 (2016): 56-69. doi:10.1213/ANE.0000000000001008