CareFusion Alaris PK Manual Del Usuario página 3

This addendum should be used in conjunction with the Alaris® PK Syringe Pump Directions For Use. The purpose of this addendum is to
provide additional material for operation when using a drug configuration based upon the Sufentanil-Gepts model. To use this drug / model
combination a suitable data set must be created, see Alaris® PK Editor Software Directions For Use.
When first starting the infusion the pharmacokinetic / pharmacodynamic models within the Alaris® PK Syringe Pump are reset to zero.
Therefore, if for any reason the pump is switched off during the surgical procedure, all current pharmacokinetic / pharmacodynamic model
information will be lost. Under such circumstances switching the pump on and restarting the infusion whilst the patient contains a significant
residual drug dose could result in an over-infusion and, therefore, the pump should not be restarted in TCI mode.
Drug : Sufentanil Model: Gepts (not weight adjusted)
Age Limit: 12 years upwards
Unit of Plasma Concentration: ng/ml
Max. Plasma concentration: 2 ng/ml
Vc = 14.3 l
k10 = 0.0645 min
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k12 = 0.1086 min
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k13 = 0.0229 min
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k21 = 0.0245 min
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k31 = 0.0013 min
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Reference from the literature : Gepts et al.: Anesthesiology 1995, 83, 1194-1204
Additional: ke0 calculated with time to peak effect 5.6 min (ke0 = 0.17559 min
An adult three compartmental PK model without any covariate, enlarged with an effect site model for Sufentanil is developed by Gepts et al.
The model is developed and clinically validated through publications in a normal adult population. The PK model is also found to be accurate
in obese patients. (Barvais et al. J Cardiothorac Vasc Anaest 2000 ; 14 : 402-8 ; Slepchenko et al. Anesthesiology 2003 ; 98:65-73; Pandin et al.
Anesthesiology 2000 ; 93: 653-61).
Recommended infusate concentrations from publication are from 1 and 5 µg/ml.
Concerning target concentrations, originally, Bailey et al (Anesth Analgesia 1993; 76 : 247-52) measured very high plasma levels of sufentanil
(> 20 ng/ml) when given alone during cardiac anesthesia. As sufentanil should always be combined with an hypnotic agent during
anesthesia, much lower concentrations should be given. In more recent studies using TCI sufentanil with the Gepts model in combination of
propofol, isoflurane and midazolam used target blood concentration between 1 and 10 ng/ml during cardiac surgery and between 0.1 and 1
during general surgery. (Barvais et al. J Cardiothorac Vasc Anaest 2000 ; 14 : 402-8 ; Slepchenko et al. Anesthesiology 2003 ; 98:65-73; Pandin
et al. Anesthesiology 2000 ; 93: 653-61). It has to be noticed that in some countries, recommended concentrations are already included into
the sufentanil drug label. In France, target concentrations between 0.4 and 2 ng/ml for cardiac and 0.15 and 0.6 for non-cardiac surgery are
included. In the latest version of Miller's Anesthesia, therapeutic concentrations of sufentanil are described as follows : predominant agent
(5-10 ng/ml; major surgery (1-3 ng/ml); minor surgery (3-6 ng/ml); spontaneous ventilation (< 0.4 ng/ml) and analgesia (0.2-0.4 ng/ml).
As Gepts et al didn't study the pharmacodynamic of sufentanil in her study, the effect site concentration is calculated using a ke0 developed
by Scott et al using a different study population than Gepts et al and measuring EEG changes as a measure of drug effect, therefore the effect
site concentration information should be handled with care (Scott et al, Anesthesiology 1985, 62, 234-241). However, using the method of
time to peak effect algorithm whereby tpeak is set at 5.6 min after bolus, the stability of the algorithm has been proved, even resulting in
beneficial clinical effects when effect compartment TCI has been administered. (Derrodde et al. Brit J Anaesth 2003, 842-9).
In patients with compromised health, (ASA 3-4), targets should be titrated with care. It might be recommended to start with a lower target
and increase following onset of drug effect.
The information above is extracted from publications and we recommend the full reading and understanding of the relevant publications
on this model, and the prescribing information, prior to use.
At the release of this document, Sufentanil administration mode using the TCI is recommended only in countries where prescribing
information is available. For other countries, the "Clinical Trial" option should be set within the Alaris® PK Editor Software until prescribing
information is available.
Effect site targeting will not trigger the Soft or Hard limit alarms set for Plasma Concentrations
TCI Precautions
Pharmacokinetic and Pharmacodynamic parameters
Model Restrictions
1000DF00450 Issue 1
Introduction
)(reference: Shafer et al Anesthesiology. 1991 Jan;74(1):53-63)
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