System Science Ph.D. Program Oregon Health & Science Univ. Complex Systems Laboratory 1 A Computer Model of Intracranial Pressure Dynamics during Traumatic.

Slides:



Advertisements
Similar presentations
History Decompressive craniotomy first described by Annandale in 1894
Advertisements

ICP and management July 2014.
Mechanical Ventilation in Special Conditions
Respiratory Calculations
BRAIN AND ANESTHESIA WHAT’S THE DEAL? Presented by : Wael Samir Assistant Lecturer of Anesthesia Revised by: Mohamed Hamdy Lecturer of Anesthesia.
Mechanical Ventilaton Ramon Garza III, M.D.. Indications Airway instability Most surgical patients or trauma Primary Respirator Failure Mostly medical.
Increased Intracranial Pressure (ICP)
Compression 1. Effects of External Compression Improved Venous and Lymphatic Circulation Limits the Shape and Size of Tissue 2.
Traumatic Brain Injury Children Torsten Lauritsen Rigshospitalet Copenhagen.
Katie Clement, MD PICU Resident Lectures 2011 Traumatic Brain Injury.
Traumatic Head injuries
Hugo Poncia. Head Trauma Epidemiology Physiology History Examination Investigations Treatments Cases.
Head Trauma NOTE: Beginning with third edition of this text, material included in this chapter has been based upon recommendations of Brain Trauma Foundation.
Fund BioImag : MRI contrast mechanisms 1.What is the mechanism of T 2 * weighted MRI ? BOLD fMRI 2.How are spin echoes generated ? 3.What are.
The Society of Neurological Surgeons Bootcamp The Society of Neurological Surgeons Bootcamp ICP Management.
Intracranial Pressure Monitoring Definition: pressure exerted by intracranial volume of: 1- Brain 2- Blood 3- CSF Normal ICP: mm Hg. Increased.
Intracranial Hypertension Fellows Conference Sept 07.
Treat a Casualty with a Closed Head Injury. Combat Trauma Treatment 2Head Injury Introduction Most common for individuals working in hazardous environments.
Intracranial Pressure in Traumatic Brain Injury Özlem Korkmaz Dilmen Associate Professor of Anesthesiology and Intensive Care Cerrahpasa School of Medicine.
Modeling Intracranial Fluid Flows and Volumes During Traumatic Brain Injury to Better Understand Pressure Dynamics W. Wakeland 1 J. McNames 2 M. Aboy 2.
Traumatic brain injury (TBI) is the leading cause of death and disability in children causing, more than 50% of all childhood deaths. Each year, more than.
System Science Ph.D. Program Oregon Health & Science Univ. Complex Systems Laboratory 1 A Tale of Two Methods—Agent-based Simulation and System Dynamics—
System Science Ph.D. Program Oregon Health & Science Univ. Complex Systems Laboratory 1 Estimation of Subject Specific ICP Dynamic Models Using Prospective.
Design of a Cranial Vascular Mechanics Model Sean S. Kohles, PhD Director, Kohles Bioengineering, Portland, OR; Adjunct Associate Professor, Mechanical.
Copyright 2008 Society of Critical Care Medicine Mechanical Ventilation 2.
Increase Intracranial Pressure
System Science Ph.D. Program Oregon Health & Science Univ. Complex Systems Laboratory 1 Calibrating an Intracranial Pressure Dynamics Model with Annotated.
Noninvasive Measurement of Intracranial Pressure by MRI (MR-ICP) Overview Noam Alperin, PhD Physiologic Imaging and Modeling Lab Department of Radiology.
The Effect of Exercise on the Cardiovascular System
Anatomy and Physiology for Emergency Care Chapter 14 Blood Vessels and Circulation.
Focus on Intracranial Pressure
Tony Figaji MBChB, MMed, FCS, PhD Head of Pediatric Neurosurgery Red Cross Children’s Hospital University of Cape Town.
Protective Lung Strategy Mazen Kherallah, MD, FCCP
1 Shock Terry White, RN. 2 SHOCK Inadequate perfusion (blood flow) leading to inadequate oxygen delivery to tissues.
Traumatic Brain Injury
Head Trauma Head Trauma Facts: 40% of multiple trauma victims have brain injuries. Brain injured patients have a death rate twice that of non-brain.
Severe Pediatric Head Injury – tips and tricks Jonathan Duff MD Division of Pediatric Critical Care University of Alberta.
ASNR 53rd Annual Meeting – Poster EP-39, Control # 1239
CURRENT PROCJECTS The Effect of AVF Size and Position on Distal Perfusion Focus: Alter diameter, length and position of fistula and monitor changes in.
Management of Intracranial Hypertension in Traumatic Brain Injury Management of Intracranial Hypertension in Traumatic Brain Injury Kiran Hebbar, MD 5/31/05.
Bodiflo LLC 1 BODIFLO LLC BodiFLO System. Bodiflo LLC 2 BodiFLO Background Injuries to the head and traumatic brain injury (TBI) make up a substantial.
Anesthesia Medication Effects on Cerebral Hemodynamics.
Modeling Steady State Intracranial Pressures in Microgravity Scott A Stevens, PhD Penn State Erie William D Lakin, PhD The University of Vermont Paul L.
RESPIRATORY 221 WEEK 4 CH.8. Oxygen transport Mixed venous blood – pulmonary capillary - PvO2 40mmHg - PAO2 100mmHg – diffuses through pressure gradient.
 By the end of this lecture the students are expected to:  Define cardiac output, stroke volume, end- diastolic and end-systolic volumes.  Define.
Touqeer Ahmed Ph.D. Atta-ur-Rahman School of Applied Bioscience, National University of Sciences and Technology 21 st October, 2013.
Presentation and Management of Raised Intracranial Pressure
Neurology Critical Care NUR 351/352 Diane E. White RN CCRN PhD.
Top Papers in Critical Care 2013 Janna Landsperger RN, MSN, ACNP-BC.
Intracranial Pressure Concepts Michelle Hill RN, BSN, CNRN, CCRN, SCRN Clinical Nurse Educator Neurocritical Care.
Cerebral Blood Flow Dr James F Peerless July 2015.
Increased Intracranial Pressure (ICP) Dr. Isazadehfar.
Managing Increased Intracranial Pressure. Introduction The cranium is a rigid compartment. Contains the brain, vessels and cerebrospinal fluid. Can not.
Intracranial Pressure Paula Ponder MSN, RN, CEN (Relates to Chapter 62,63 Intracranial Pressure in the textbook)
A Mathematical Model of Idiopathic Intracranial Hypertension Thakore, Nimish J 1 ; Stevens, Scott A 2 ; Lakin, William D Department of Neurology,
RAISED ICP Atandrila Das. Monro-Kellie Doctrine Cranial cavity is a rigid sphere Filled to capacity with non compressible contents Increase in the volume.
INTRACRANIAL PRESSURE
Increased Intracranial Pressure (ICP)
How can we create and analyze ‘new signals’ using ICM+?
INTRACRANIAL PRESSURE
Increased Intracranial Pressure
Pediatric Traumatic Brain Injury in 2012
Cryotherapy Addition of cryotherapy to intermittent compression has shown the best results in the reduction of post acute injury edema.
Monitoring the injured brain: ICP and CBF
USA Today: The report also said that doctors concluded Piazza suffered from "multiple traumatic brain injuries," including a fractured skull and.
Pediatric Traumatic Brain Injury in 2012
What comes first? The dynamics of cerebral oxygenation and blood flow in response to changes in arterial pressure and intracranial pressure after head.
AUTOREGULATIONOF CEREBRAL BLOOD FLOW
W. Wakeland 1,2, J. Fusion 1, B. Goldstein 3
Presentation transcript:

System Science Ph.D. Program Oregon Health & Science Univ. Complex Systems Laboratory 1 A Computer Model of Intracranial Pressure Dynamics during Traumatic Brain Injury that Explicitly Models Fluid Flows and Volumes W. Wakeland 1 B. Goldstein 2 L. Macovsky 3 J. McNames 4 1 Systems Science Ph.D. Program, Portland State University 2 Complex Systems Laboratory, Oregon Health & Science University 3 Dynamic Biosystems, LLC 4 Biomedical Signal Processing Laboratory, Portland State University This work was supported in part by the Thrasher Research Fund

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 2 Objective To create a computer model of intracranial pressure (ICP) dynamics To use model to evaluate clinical treatment options for elevated ICP during traumatic brain injury (TBI)  Present work: replicate response to treatment  Future Work: predict response to treatment  Long term goal: optimize treatment

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 3 Approach Fluid volumes as the primary state variables  Parameters estimated: compliances, resistances, hematoma volume and rate, etc.  Flows and pressures caluculated from state vars. & parameters  Simplified logic used to model cerebrovascular autoregulation  Resistance at arterioles changes rapidly to adjust flow to match metabolic needs, within limits  The logic responds to diurnal variation or changes in ICP, respiration, arterial blood pressure, head of bed (HOB), etc.

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 4 Approach (continued) Trauma and therapies modeled  Hemorrhage and edema  Cerebrospinal fluid drainage, HOB, respiration rate Model calibrated to specific patients based on clinical data  Recorded data includes ICP, ABP, and CVP  Data is clinically annotated  Data is prospectively collected per experimental protocol  Protocol includes CSF drainage, and changes in head of bead and minute ventilation Tested capability of model to reproduce correct physiologic response to trauma and therapies

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 5 Model State Variables and Flows Link to Eqns. Link 2 Full D.

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 6 Clinical Data for ICP before and after CSF Drainage, Patient 1

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 7 Model Calibrated to Fit the Clinical Data for Patient 1 Estimated parameters Initial hematoma volume = 24 mL Hematoma increase rate = 0 CSF drainage volume = 6.5 mL CSF uptake resistance = 160 mmHg/mL/min This high value implies a significant impediment to flow/uptake  Presumably due either to the initial injury, subsequent swelling, or a combination of the two

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 8 Model Response to CSF Drainage, Patient 1

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 9 Prospective Clinical Data: Head of Bed Change, Patient 2 ICP (mmHg)

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 10 Model Calibration for HOB Change, Patient 2 Estimated parameters for lowering HOB  Initial hematoma volume = 6 mL  Hematoma increase rate =.5 mL/min.  Distance from heart to brain = 40 cm  CSF absorption resistance = 24 mmHg/mL/min Estimated parameters for raising HOB  Hematoma increase rate =.5 mL/min.  Distance from heart to brain = 45 cm (revised est.)

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 11 Model Response to Changing HOB, Patient 2

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 12 Prospective Clinical Data: Respiration Change, Patient 2 ICP (mmHg)

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 13 Model Calibration for Respiration Change Estimated Parameters for AR process  Flow multiplier = 75 ml/mmHg  PaCO 2 setpoint = 34 mmHg  PaCO 2 offset = 64 mmHg  Conversion factor = 2 mmHg-breaths/min.  Time constant for PaCO 2 response = 2.5 minutes The model was not able to fully replicate patient’s response to the VR change  Most likely due to the simplified cerebrovascular autoregulation logic

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 14 Model Response to Changing Respiration, Patient 2

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 15 Summary We developed a simple model of ICP dynamics that uses fluid volumes as primary state variables ICP calculated by the model closely resembles ICP signals recorded during treatment and during an experimental protocol  CSF drainage, changing HOB and respiration Cerebrovascular autoregulation logic only partially captured the patient’s response to respiration change

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 16 Key Variables and Equations Six intracranial compartments  Arterial blood (ABV)  Capillary blood (CBV)  Venous blood (VBV)  Cerebral spinal fluid (CSF)  Brain tissue (BTV)  Hematoma (HV) Compartmental pressures  P ab = ICP + (ABV)/(Arterial Compliance)  P cb = ICP + (CBV)/(Capillary Compliance)  P vb = ICP + (VBV)/(Venous Compliance) Intracranial Pressure (ICP)  ICP = BaseICP  10 (Total Cranial Volume–Base Cranial Volume)/PVI Back

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 17 Back

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 18 Hypothetical Test of the Model min min. Perturba- tion Arterial blood escapes to form a 25 mL hematoma 12 mL Cerebral spinal fluid drained ResponseICP increases to 24 mmHg Venous and arterial blood is forced from the cranial vault ICP decreases to 10 mmHg Venous and arterial blood volumes normalize

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 19 Time Plot for Hypothetical Test of Model

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 20 CSF Drainage Submodel

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 21 Head of Bed Logic

Oregon Health & Science Univ. Complex Systems Laboratory System Science Ph.D. Program 22 Cerebrovascular Autoregulation (AR) Logic