Neurology
tempedy® adjusts the body core temperature to achieve normothermia in an safe, effective and fully-automatic way.
We focus primarily on three therapeutic areas:
(1) Analgosedated / ventilated ICU patients
(2) Awake, acute stroke patients
(3) Neuro-ICU patients with sepsis
(1) Analgosedated / ventilated ICU patients
Background:
Fever, defined as elevation of body core temperature 38°C, is common in critically ill patients.1,2
More than 80% of all neuro-intensive care unit (ICU) patients will develop at least 1 febrile episode during hospitalization.3,4
Importantly, it has been shown that even elevation of brain temperature alone is markedly deleterious in the setting of intracranial pathology, such as ischemic stroke or intracerebral hemorrhage (ICH).5–7
All of these aspects suggest that it might be beneficial to start treatment of fever in patients with severe brain injury at an early stage or even to maintain normothermia prophylactically.
In many diseases, fever is an independent predictor of unfavourable outcome, and therefore, early treatment of hyperthermia has nowadays become the standard of care.2,6,8–10
Although short-term hypothermia is nowadays considered to improve outcome in patients after resuscitation from cardiac
arrest, data on prolonged hypothermia in patients with acute intracranial pathology are controversial.21
Because severe adverse effects of mild to moderate hypothermia (ie, body core temperature 33°C to 35°C) may outweigh its beneficial effects in ICU patients with various diseases, the use of therapeutic hypothermia is under debate. 25, 26
Clinical rationale for tempedy:
Cooling with “feedback devices” is more efficient compared to conventional methods (cold air, ice packs etc.). 11
As all patients will require infusions anyway, hence tempedy® as an automatic infusion system can easily be implemented into the multimodal ICU treatment approach and facilitate fever therapy as well as prophylactic normothermia strategies.
Peripheral infusions of saline in chilled form can be used as an adjunct therapy to achieve euthermia and control fever. Temperature modulation with tempered fluids is a proven and accepted method, also as e.g. cold infusions also are effective for treatment of refractory fever (elevated temperature despite acetaminophen and cooling blanket application; Neurology 2006; 66; 1739-1741). The temperature modulating efficacy and safety of cold crystalloid fluids have been extensively studied also in the area of cardiac arrest; in this indication, patients were cooled very rapidly with rates of up to -4.0°C/h. 12
Using intravenous coolants in an on-demand, temperature-guided and supervised treatment setting seems most reasonable to avoid potentially unsafe use of extended fluid volumes and infusion times. 13
Furthermore tempedy is an highly effective intravascular approach, yet there is not an increasing risk for thromboembolic events which is present in other modalities (e.g. Mueller et al in Neurocrit Care. 2014 Oct;21(2):207-10; Risk of thromboembolic events (TEE) - patients in the ECC group suffered more frequently from TEE (37 %) than those with a Central-Venous-Line CVL (5 %) .
There is an ongoing debate and clinical indicators that surface approaches have higher rates of shivering and hence require aggressive shivering control measures / more sedation and higher doses of paralytics
(2) Awake, acute stroke patients
Background:
Up to 61% of patients with ischemic stroke suffer from fever within the first 48 hours after symptom onset
Fever in patients with acute cerebral injury is associated with higher mortality, worse functional outcome and longer in-hospital and intensive care unit stays
Guidelines recommend monitoring of body temperature as essential component of care in stroke units and treating fever in case of elevated temperature in parallel to systematic search for possible infections
Oral antipyretics are only marginally effective in lowering elevated body temperature and may have unintended adverse consequences
Proposal for a solution with tempedy®:
Integration of effective and proven physical cooling method (cold infusions) within any fever treatment SOP; this physical cooling approach is non-additionally invasive and reduces nursing workload due to the automatic and bio-feedback controlled application
As demonstrated within a pilot study of 10 awake acute stroke patients, it is even possible to induce hypothermia via cold infusions in this patient population (Stroke 2009; 40; 1907-1909)
(3) Neuro-ICU patients with sepsis
Clinical rationale:
Precise and rapid application of infusions (flow rates up to 250ml/min) for fluid management, in parallel automatic and body temperature feedback controlled temperature management, e.g. in case body temperature exceeds a predefined threshold all applied fluids will be pre-cooled (down to 4°C) in order to support a fever reduction strategy.
References:
1. Diringer MN, Reaven NL, Funk SE, Uman GC. Elevated body temperature
independently contributes to increased length of stay in neurologic
intensive care unit patients. Crit Care Med. 2004;32:1489 –1495.
2. Diringer MN. Treatment of fever in the neurologic intensive care unit
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559–564.
3. Albrecht RF, Wass CT, Lanier WL. Occurrence of potentially detrimental
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4. Donowitz LG, Wenzel RP, Hoyt JW. High risk of hospital-acquired
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D’Alessandro R. Fever in acute stroke worsens prognosis: a prospective
study. Stroke. 1995;26:2040 –2043.
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21. Holzer M, Behringer W, Janata A, Bayegan K, Schima H, Deckert Z,
Losert U, Laggner AN, Sterz F. Extracorporeal venovenous cooling for
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