This product in its environment, Introduction, Treatment algorithms – ZOLL Thermogard XP IVTM Physician Manual User Manual
Page 11: Max power (max), Controlled rate, This product in its environment 10, Introduction 10, Treatment algorithms 10, Max power (max) 10, Controlled rate 10
ZOLL IVTM™ System
Physicians' Manual
600248-001 Rev 3
10
This Product in its Environment
Introduction
The first law of thermodynamics can only be applied after defining the system. For
our purposes the system consists of three elements:
1. The patient:
• Is intubated and sedated.
• Is warmer than the environment and therefore will lose heat to the
environment.
• Will lose more heat to the environment if wet than if dry.
2. The environment. This is typically controlled by air conditioning that is far
more powerful than the patient (i.e., it will react to overcome any heat the
patient adds to the environment). Within this discussion, outside of the
performance of the IVTM System , the single most significant effect upon
the patient is the rate of heat loss to the environment.
NOTE: When comparing catheter performance, only results obtained
from controlled in-vitro methods should be used. Heat exchange to the
environment within the clinical setting can be significant and variable
depending upon environmental conditions and the degree to which the
patient is able to maintain his/her body temperature.
3. There are two heat transfers that occur in the IVTM System:
• Between the fluid in the cold well of the IVTM System and the saline
in the coil of the Start-Up Kit.
• Between the saline in the catheter balloons and the blood of the
patient.
The IVTM System responds to both the difference between the patient’s temperature
and the set-point and to the rate of change of the patient’s temperature. The system
will add or remove heat to maintain the patient at the set-point.
Treatment Algorithms
There are four treatment algorithms in RUN: “Max Power”, “Controlled Rate”,
"Warming", and “FEVER”.
Max Power (MAX)
In this treatment option, the IVTM System seeks to make the patient’s temperature
the same as the selected target temperature. It will keep the saline pump operating
unless the patient’s temperature “inverts”. This occurs whenever:
A. Bath Temperature > Patient Temperature > Target Temperature,
OR
B. Bath Temperature < Patient Temperature < Target Temperature.
Controlled Rate
In this treatment option, the IVTM System will attempt to move the patient’s
temperature to the target temperature at the programmed rate of heat exchange (°C