Increasing threat of the next influenza pandemic
H5N1 in wild birds & poultry
Confirmed human cases: 21 (year-to-date); deaths 18 (85.7%)
Past experiences suggest severe impact
Surge demand
Social disruption Nations With Confirmed Cases H5N1 Avian Influenza P d i Fl
Economic los

DeLaurentis, Po-Ching C.

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HOSPITAL STOCKPILE FOR INFLUENZA PANDEMIC PREPAREDNESS PLANNINGRCHE Brown Bag TalkMarch 7, 2008Po-Ching C. DeLaurentisIE Ph.D. CandidateOutline? Introduction2? Research Motivation & Objective? Analytical Methods? Future Work & Practical ChallengesBackground? History– three major flu pandemics in the 20th century3? Spanish Flu, 1918–1919? H1N1 virus caused 3 waves in the US? An estimated 17 million died in India, 500,000 in the US and 200,000 in the UK? Asian Flu, 1957-1958? H2N2 virus? About 69,800 people in died the US ? Hong Kong Flu, 1968-1969? H3N2 virus? About 34,000 deaths in the US? Several pandemic threatsCurrent Condition4? Increasing threat of the next influenza pandemic? H5N1 in wild birds & poultry? Confirmed human cases: 21 (year-to-date); deaths 18 (85.7%)? Past experiences suggest  i tsevere mpac? Surge demand? Social disruption Nations With Confirmed Cases H5N1 Avian InfluenzaP d i Fl? Economic lossan em c u.govPotential Impact of Next Flu Pandemic? Economics5? Indiana: Projected GDP Loss from Severe Pandemic of $14 billion by Trust for America’s Health (March 22, 2007)? Healthcare? Indiana Projected Number of Illnesses: 1 863 000 , ,(severe case)? Indiana Projected Lives Lost: 49,000 (severe case)? Social Disruption? School closure? Lost workforceHealthcare Systems Preparedness Planning? World Health Organization (WHO), Centers for Disease Control 6and Prevention (CDC), and G. Juckett (2006):? Checklists, planning guidelines, planning guides? Pharmaceutical interventions– vaccines, antivirals…etc.? Non-pharmaceutical interventions ? Patient isolation  quarantine  social distancing  travel restriction  and , , , ,personal protection & hygiene? Strategic National Stockpile (SNS) ? Antibiotics, chemical antidotes, antitoxins, life-support medications  IV administration  airway maintenance supplies  , , ,and medical/surgical items.Research Motivation? Havlak et al. (2002)7? Strategic National Stockpile (SNS)– sufficient levels?? Past success– point and centralized incidents? Toner & Waldhorn (2006)? Surge Capacity Needs? Lack of guidelines and specificityThe Health Human Services Secretary Mike Leavitt: “ …I worry about local and state governments and private entities relying on the federal government instead of preparing themselves. Our national stockpiles are set up to cover gaps, not to provide everything for b d ’’  every o y(http://secretarysblog.hhs.gov/)Research Objective? Focus:8Hospital stockpile issues under surge conditions with uncertainty? Objective: To create a set of policy alternatives for public health and hospital decision makers in determining:–Hospital stockpile levels of critical medical items and ordering policyMedical Supplies for Pandemic Flu? Excluding Flu Vaccines9? Critical Medical Supplies for? Protecting health care providers: Personal protective equipment (PPE)? Patient care? Examples: masks, patient gowns, goggles, isolation gowns, shoe cover, disposable linens…etc.Research Challenges10? Uncertainties? Timing: the onset of th  fl  d iSi(t)e u pan em c? Delay in information transmittedSmaxStockpile Level? How it will spread? Severity of the fluTtT +μToday? Attack rate?Mortality ratep p pDuration of a Pandemic, μpOnset of Flu Pandemic? Duration? Number of wavesProposed Approaches11? Individual hospitals’ stockpile decisions:– Stochastic optimization? Group decision making: mutual aid agreement among hospitals for sharing supplies– Game theoretical approachStochastic OptimizationMi i i ti  (  i i ti ) f  f ti  i  th  12? n m za on or max m za on o a unc on n epresence of randomness in the optimization processpandemicshortageTCEpandemicprestockpileTC ⎥⎦⎤⎢⎣⎡+−⎥⎦⎤⎢⎣⎡ max   min? Constraints:? Budget? Inventory BalanceGame Theoretical Approach? Game theory: a framework for modeling the world of 13competition and cooperation? Basic elements of a game: ? Players ? Preferences & strategies/actions? Payoff/utility functions? Players make decisions in response to other players’ actions? Nash equilibrium (NE): the set of all players’ decisions such that none of them has any incentive to deviate from his decision.Game Model• Model Setup: a group of hospitals in a stockpile ‘game’.  14– Players:  n hospitals– Strategy/Decision: stockpile level, si, of each hospitalC t F ti  t t l t k il  t i l di  h i  h ldi  – os unc on: o a s oc p e cos nc u ng purc as ng, o ng,and penalty cost due to shortage– Each hospital plans to respond to a pandemic. But there is a b bilit   th t it ill t d t th  t f th  pro a y, ρi, a w no respon a e onse o epandemic– When a hospital is not responding, it shares a fraction, αi, of its t k il  ith th  h it ls oc p e w o er osp a sPurchasing Holding Cost of borrowing from othersPenalty cost of shortageTwo-hospital ExampleObjective Function151.551.6x 104 s2: 350s2: 500• The objective function is piecewise linear and convex• The slope of the objective function 1.451.5J1s2: 870 increases as s1 increases• Best response is the best strategy that a player can do given the 1.351.4other play’s strategy• Ex: (Red line) Given that s2 is 870, the best strategy of hospital 1 is 0 200 400 600 800 10001.3s1 setting its stockpile at 400400Best Response Points:450 570Two-hospital Example (cont’d)Best Response Function16• si*(sj) is the best response f i f h i l i9001000  s1*(s2)*( ) unct on o   osp ta    as a function of hospital j’s stockpile level, sj5006007008002s2 s1• In a two‐player game, a NE lies where the two best response functions200300400s     intersect0 200 400 600 800 10000100s1 NE: (580, 300)Future Work? Extension of n-hospital game for group decision 17making? Stochastic optimization for individual hospital stockpile decisions? Comparison of the resultsPractical Challenges? Financial Commitment18? Management of Stockpile? Sharing of Supplies during Pandemics19Q ti  d C t ?ues ons an ommen s

Hospital Stockpile for Influenza Pandemic Preparedness Planning

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Hospital Stockpile for Influenza Pandemic Preparedness Planning

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