COURTNEY J. COOK, DNP, ACNP-BC

Induced Hypothermia in Neuro-critical Care:

ESTABLISHING A STANDARDIZED SHIVERING ASSESSMENT AND

TREATMENT PROTOCOL

PROBLEM STATEMENT

• In neurocritical care, the use of induced hypothermia (IH) is an emerging treatment modality for the management of:• Refractory intracranial hypertension • Cerebral edema

• Shivering is a common complication of IH.

• In this project, the Neuroscience Intensive Care Unit (NSICU) studied at a level I Trauma Center lacked a standardized shivering assessment and treatment protocol.

• Aim of Project: Establish a protocol to provide a consistent and reliable measurement of shivering and corresponding treatment algorithm.

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BACKGROUND AND KEY CONCEPTS DEFINED

• Induced hypothermia (IH): 33-35°C.

• Indications: Malignant cerebral edema or refractory intracranial hypertension

• Traumatic brain injury (TBI), malignant ischemic stroke, subarachnoid hemorrhage (SAH), and intracranial hemorrhage (ICH)

• Reduces cerebral edema, intracranial pressure, and metabolic demands

• Shivering defined3

SIGNIFICANCE OF PRESSURE AND EDEMA IN THE CRANIAL VAULT

• Monro-Kellie hypothesis:

Cranial vault (v)=brain matter(v)+ csf(v)+blood(v)+tumor(v)

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HOW IH IS PERFORMED

•Endovascular cooling

•External (surface cooling)

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COMPLICATIONS OF IH AND THE SIGNIFICANCE OF SHIVERING

• Complications effect tissues at the molecular level and ultimately have repercussions for multiple organ systems.

• Shivering has the potential to increase metabolic demands by up to 600% (Badjatia et al, 2008).

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TEMPERATURE REGULATION

• Achieved through cutaneous vasodilation and sweating or vasoconstriction and shivering in order to maintain homeostasis 37°C, or 98.6°F.

• Two heat capacitances (energy storage units): • 1. core • 2. skin

.

7(Guyton & Hall, 2011).

THE ROLE OF SHIVERING IN TEMPERATURE REGULATION

• Standard heat production from shivering is 252 kcal/hr

• Example: If skin heat loss from radiation is 80 kcal/hr, the skin temperature gradient will double.

(Riggs, 1970)

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THE MULTIPLICATIVE FACTORS

• Two primary factors influence the multiplicative factors

• 1. the shivering initiation multiplier (from the cooler core temperature)

• 2. the shivering multiplier from the normalized temperature difference

(Riggs, 1970) 9

THE SECOND MULTIPLICATIVE FACTOR

• Also known as the “normalizing factor,” K, and is dependent on core temperature

• When the temperature falls below 37°C, a linear relationship exists that allows for the K to be determined.

• For instance, if the core temperature is 35°C, then K is 25°C

(Riggs, 1970) 10

THE SUMMATION OF THE MULTIPLICATIVE FACTORS

(Riggs, 1970)11

CURRENT PRACTICE IN THE NEUROSCIENCE INTENSIVE CARE UNIT (NSICU)

• Induced hypothermia is achieved via surface cooling.

• Goal temperature is 35°C

• Shivering is inconsistently assessed as either present or absent (observational)

• Pharmacologic management typically involves propofol infusions, fentanyl (IV boluses prn), and versed (IV boluses prn)

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ESTABLISHING A PROTOCOL FOR SHIVERING ASSESSMENT AND

MANAGEMENT

• Comprehensive literature review

• Synthesis of information is limited by gaps in the literature.

• Lack of randomized clinical trials

• No standard IH goal temperature (ranging from 32°C to 35°C).

• Newer modality and therefore, less research has been conducted.

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METHODOLOGY

• The Deming Model: Plan, Do, Study, Act (PDSA) theoretical framework

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METHODOLOGY CONTINUED

• Plan: A needs assessment was be conducted.

• A comprehensive approach allowed for firm understanding of current practice and limitations

• Do: Incorporating the Columbia BSAS into the final NSICU protocol was the aim since it has been validated through clinical research.

• The pharmacological algorithm was be revised to address medications identified in multidisciplinary literature (anesthesia, neurology, pharmacology).• Demerol and Ondansetron

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METHODOLOGY CONTINUED

• Study: A retrospective chart review was completed on all patients receiving IH from January 1, 2012 through January 1, 2013

• Goal N=30

• The literature review provided the foundation for drafting the proposed shivering assessment and management protocol.

• The areas of clinical interest for data collection were as follows:

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AREAS OF RESEARCH INTEREST

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METHODOLOGY CONTINUED

• Act: The proposed protocol will require a clinical research study to evaluate efficacy and impact on patient outcomes. This may be a future extension of this research project.

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THE COLUMBIA BEDSIDE SHIVERING ASSESSMENT SCALE (BSAS)

(Badjatia et al, 2008). 19

THE COLUMBIA SHIVERING TREATMENT ALGORITHM

(Badjatia et al, 2008) 20

(Weant et al., 2010)21

THERAPEUTIC CLASSES AND EFFECTS

• Nonopiod analgesics (acetaminophen)

• Anxiolytics (buspirone)

• N-methyl-D-aspartate receptor agonists (Magnesium)

22(Weant et al., 2010)

THERAPEUTIC CLASSES CONTINUED

• A2-adrenergic agonists (dexmedetomidine, opiates)

• Narcotic Analgesics (fentanyl, meperidine)

• General anesthetics (propofol)

• Paralytics (vecuronium)

(Weant et al., 2010) 23

THERAPEUTIC CLASSES CONTINUED

• Additional medications considered for incorporation into the shivering management protocol that were not included in the BSAS:

• Ondansetron (5 HT agonist)

• Tramadol (inhibits norepinephrine/serotonin uptake)

• Clonidine (A2 agonist)

• Nalbuphine (mixed agonist-antagonist opioid)

• Dantroline (inhibits skeletal muscle excitation-contraction coupling)

• Doxapram (stimulates dopamine release)

24(Weant et al., 2010).

CONCLUSION

• Purpose-Establish a Shivering Assessment and Treatment Protocol in the NSICU

• Methodology-Deming Model for continuous quality improvement• Data Collection-retrospective chart review January 1, 2012 through

January 1, 2013• Goal N=30• Through literature review, consider additional pharmacologic options

to reduce shivering.• Present protocol to Nursing Policy and Standard Committees for

review• Moving forward-consider a formal research study as a future

extension of this project to follow implementation and clinical outcomes

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QUESTIONS?

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REFERENCES:

• Ash, L. (2000) Counter Current Heat Exchange. Retrieved from: http://www.biology.ualberta.ca/facilities/multimedia/uploads/zoology/counter%20current.html

• Badjatia, N. (2006). Therapeutic temperature modulation in neurocritical care. Critical Care Neurology, 6: 509-517.

• Badjatia N., Strongilis, E., Gordon, E., Prescutti, M., Fernandez, L., Fernandez, A…Mayer, S. A. (2008) Metabolic impact of shivering during therapeutic temperature modulation. Stroke, 39:3242-3247.

• Benzinger, T. H. (1963). “The Human Thermostat” Temperature, Its Measurement and Control in Science and Industry (637-665). New York: Reinhold Publishing.

• Bernard, S.A., & Buist, M. (2003). Induced hypothermia in neurocritical care medicine: a review. Neurologic Critical Care, 31(7) 2041-2051.

• Bhardwaj, A., Alkayed, N.J., Kirsch, J.R., Traystman, R.J. (2007). Acute Stroke: Bench to Bedside (Neurological Disease and Therapy). Informa Healthcare USA. New York, NY.

• Choi, H. A., Sang-Bae, K., Presciutti, M., Fernandez, L., Carpenter, A. M., Lesch, C…Badjatia, N. (2011). Prevention of shivering during therapeutic temperature modulation: The Columbia anti-shivering protocol. Neurocritical Care Society, 14, 389-394.

• Deming, W.E. (1950). Elementary principles of the statistical control of quality-a series lecture. Japanese Union of Scientist and Engineers.

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REFERENCES CONTINUED

• Doufas, A. G., Lin, C. M., Suleman, M. I., Liem, E. B, Lenhardt, R., Morioka, N…Sessler, D. I. (2003). Dexmedetomidine and meperidine additively reduce the shivering threshold in humans. Stroke, 34, 1218-1223.

• Ford, A. (2012). Physiology exercises: Body temperature control with shivering. Retrieved from: http://public.wsu.edu/~forda/Physiology.pdf

• Geocadin, R. G. & Carhuapoma, J. R. (2005) Medivance arctic sun temperature management system. Neurocritical Care, 3, 63-67.

• Guyton & Hall (2011). Medical Physiology. Saunders: Philadelphia, PA. • Hand, H., Searcy, M., Schulman, C.S. (2011). Shivering avoidance in the neuronally

injured patient: Impact on temperature management technology decisions• Kochanek, P. M. (2009). The brain, the heart, and therapeutic hypothermia. Cleveland

Clinic Journal of Medicine, 76, S8-S12.• Lenhardt, R., Sungur-Orhan, M., Komatsu, R., Govinda, R. Kasuya, Y., Sessler, D. I.,

Wadhwa, A. (2009). Suppression of shivering during hypothermia using a novel drug combination in healthy volunteers. Anesthesiology, 111(1), 110-5.

• Liu-DeRyke, X. & Rhoney, D.H. (2008). Pharmalogical management of therapeutic hypothermia-induced shivering. Society of Critical Care Medicine.

• Logan, A., Sangkahand, P., & Funk, M. (2011). Optimal management of shivering during therapeutic hypothermia after cardiac arrest. Critical Care Nurse, 31(6):e18-e30.

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REFERENCES CONTINUED

• Marshall, P.S. & Siegel, M.D. (2009). Therapeutic hypothermia. American College of Chest Physicians (23): 1-17.

• Miller, C.A. (2011). Pharmacological treatment of post-anesthetic shivering: an educational outreach project. Texas Christian University Harris College of Nursing and Health Sciences, 1-57.

• Mokri, B. (2001). The Monro-kellie hypothesis: Applications in CSF volume depletion. Neurology, 56(12):1756-1748.

• Mokhtarani, M., Mahgoub, A. N., Morioka, N., Doufas, A. G., Dae, M., Shaughnessy, T. E…Sessler, D, I. (2001). Buspirone and meperidine synergistically reduce the shivering threshold. International Anesthesia Research Society, 93, 1233-1239.

• Paulev, P.E. & Zubieta-Calleja, G.Z. (n.d.) New Human Physiology. Chapter 21: Thermo-regulation, temperature, and radiation. Retrieved from: http://www.zuniv.net/physiology/book/chapter21.html

• Riggs, D. (1970). The mathematical approach to physiological problems. Baltimore: Williams & Wilkins.

• Ropper, A. H. (2012). Hyperosmolar therapy for raised intracranial pressure. The New England Journal of Medicine, 367:746-752.

• Sakoh, M. & Gjedde, A. (2003). Neuroprotection in hypothermia linked to redistribution of oxygen in brain. American Journal of Physiology: Heart and Circulatory Physiology, 285(1):H17-25.

• Weant, K.A., Martin, J.E., Humphries, R.L., Cook, A.M. (2010). Pharmacologic options for reducing the shivering response to therapeutic hypothermia. Pharmacotherapy, 30(8); 830-841.

• Witte, J.D. & Sessler, D.I. (2002). Perioperative shivering: physiology and pharmacology. Anesthesiology, 96(2):467-484.

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