Vintage Big Med – D Newman | Pandemic flu planning: A flow is a quantification of assumptions – Dec 2006

Pandemic Flu Planning: “A Flow is a Quantification of Assumptions” by David A H Newman

[Dec 6 06]

References. I have made use of three references: 1] Government of Ontario Flu Pandemic Plan, Chapter 17 Acute Care Services & 17a: Tools; 2] Shoppers Drug Mart Healthwatch Pamphlet: Flu; and 3] Government of Ontario Pamphlet, “What you should know about a flu pandemic.”  April 2006.

My own comments are enclosed in brackets [like so].

Flu and Pandemic Flu Facts

FLU

Flu is caused by influenza A and B viruses.

It is spread mainly by virus in the air.

It finds a comfortable home in your airways. It starts to be contagious 1 day before you first experience symptoms and remains contagious for at least 5 days after symptoms start.

Flu can lead to serious complications: pneumonia, bronchitis, sinus infections, ear infections, dehydration, and in very serious situations, death.

Ordinary flu happens every year: usually from November to April – and then stops.

Pandemic flu usually comes in two or three waves several months apart. Each wave lasts 2 -3 months.

5%-20% of the population may get the flu in any given year.

A yearly flu shot reduces risk of catching flu by 70-90%.

PANDEMIC FLU

A pandemic is distinguished by its scope: it is a worldwide epidemic.

A pandemic flu strain often develops when an animal or bird virus mixes with a human virus to form a new virus. Because people have little or no immunity, the disease can spread faster than with an ordinary flu.

The symptoms are the same as with an ordinary flu but can be much more severe.

There were three flu pandemics in the 20th century: the most deadly, the “Spanish Flu” in 1918-19 killed 20,000,000.The death rate was highest among healthy adults in their 20’s and 30’s. [The Median Age of Ontarians is 37].

A flu pandemic could happen any time.

We can’t predict just how society will be affected until we learn how strong the virus is.

There is no existing vaccine for pandemic flu. It will take 4-5 months after the start of the pandemic to develop a vaccine.

Drugs used to treat ordinary flu may also help people with pandemic flu but we may not have a large enough supply, and we won’t know how effective they are until the virus is identified.

ASSUMPTIONS

[“A ‘FLOW’ IS A QUANTIFICATION OF ASSUMPTIONS”]

Based on CDC’s U.S. FluSurge Forecasting model and an assumed 35% Influenza Attack Rate —

Over an eight week pandemic:  [there might be 3 such waves in a pandemic year]

Admissions:

Wk 1 Wk 2 Wk 3 Wk 4 Wk 5 Wk 6 Wk 7 Wk 8
3675 6125 9188 11638 11638 9188 6125 3675

Peak admissions/day: 1814

Deaths:

Wk 1 Wk 2 Wk 3 Wk 4 Wk 5 Wk 6 Wk 7 Wk 8
726 1209 1814 2298 2298 1814 1209 726

 

If you live in Ontario: during the first wave —

You have 1 chance in 3 of catching the pandemic flu

If you catch it, you have 1 chance in 2 of needing to visit your family doctor

and 1 chance in 70 of needing to be hospitalized

If you need to be hospitalized, you have 1 chance in 5 of dying there.

An unknown proportion of the population will develop health complications.

These levels are at least six times greater than typical hospitalizations for influenza and pneumonia during inter-pandemic periods.

[If you don’t get the pandemic flu in the first wave, your odds improve greatly:

*improved natural immunity from the 1st wave experience

*probable availability of a pandemic flu vaccine

*much better understanding of how to deal with the virus]

Resources needed by Hospitalized Influenza Patients:

100% using an acute bed for 5 days

15% using ICU beds for 10 days

7.5% using ventilator support for 10 days

If the Assumptions hold:

At the peak of the pandemic, influenza patients will use:

52% of all Acute Care Beds

170% of ICU Beds

117% of Ventilator-supported Beds

Current Demand for hospital services is already high: ICU Beds are utilized 90% daily.

The FluSurge model does not take into account Health Care Worker absenteeism but the Plan assumes that staff will contract influenza at the same rate as the general population in their communities. [History suggests staff will come down with pandemic flu at a much higher rate, and fatalities will be disproportionately high — especially in the first weeks. If so, the net effect will be to seriously reduce availability of trained staff as the pandemic goes on: the impact will be particularly grave should a second wave and then a third wave hit]

[The Model does not consider how patients will be moved to and from hospitals: Ontario is a big province with a population of 12 million (5 million households). However, Ontario is 80% urban, and most live in the so-called “Golden Horseshoe – from Oshawa to Niagara, including the Greater Toronto Region].

DEVELOPING HOSPITAL SURGE CAPACITY

There has to be a Phased Approach:

*Deferring non-influenza care

*Dynamic use of influenza Triage

*Dynamic Use of Admission/Discharge Criteria

These will vary according to available and needed local hospital resources.

Specifically —

*Defer Services for Non-Life-Threatening patients.

*Discharge ALC (Alternative Level of Care) patients to Long-Term Care.

*Discharge acute patients and inpatients to home care.

*Create “flex-beds” from reserved or recently closed beds.

*Deploy freed-up beds for influenza patients.

*Use Ventilator Capacity anywhere sufficient oxygen is available:

ER, post-anesthetic care units.

*Cohort infectious and non-infectious patients.

Re-deploy staff.

*Defer holidays and leaves of absence.

*Establish 12 hour shifts.

*Train non-clinical staff to handle support services: meals, personal care, patient movement, cleaning, etc. and support for health care workers and families (child care, pet care, etc)

*Coordinate with other hospitals.

*Encourage participation of public in Home Health Care courses before the pandemic.

*Cross-train clinical staff.

[Wait until the Pandemic strikes. Then count backward 1 year, and initiate training].

MASS EMERGENCY CARE DECLARATION

AND CRITICAL CARE TRIAGE

With the assumed 35% Attack Rate the phased development of Surge Capacity will not be enough to meet the Peak Demand. Accordingly, a Mass Emergency Care condition will have to be declared: this will have “substantial legal, regulatory, and logistical implications.”

The type of Triage contemplated is only justifiable in an Overwhelming Crisis i.e. when all resources are in danger of being exhausted.

Principles

*All patients will be cared for – one way or another. [True, but not very comforting.]

*Triage is a practical application of Ethics [Everything is.]

*Fairness and Justice will prevail. [How about Compassion?]

*Based on Clear and Transparent Criteria.

Timely Accurate Information is vital

Health Care providers will need real-time data about patient outcomes during a disaster; in order to modify criteria and prevent over- or under-triage. The Protocol will evolve with time and use.

Triage Models

No Triage systems have been developed yet for use in critical care or medical illnesses but there are models available to draw on:

Illness Severity Scoring Systems: “cumbersome and impractical during a disaster when human resources are scarce.”

Military Triage Systems: “devised specifically for Trauma and not for medical conditions or biological events.”

SEIRV Triage System: “developed for use in Bio-Terrorism attacks.”

Categorizes patients but does not address Resource Allocation.

Uses ‘Inclusion’, ‘Exclusion’, and ‘Minimum Qualifications for Survival (MQS)’, to guide triage decisions – “which should be part of all Critical Care Triage Systems.”

Sequential Organ Failure Assessment Score (SOFA): “may be useful as a component of a Triage System.” It uses general physiologic parameters applicable in a wide variety of conditions.

Inclusion Criteria

Identifies patients who may benefit from admission to critical care: focusing primarily on respiratory failure.

Exclusion Criteria

Identifies those needing a level of resources which cannot be met in a pandemic, and even if ICU resources were found they would have a very poor chance of survival (SOFA Score of > 11 i.e. mortality rate of > 90% even with full critical care). For example —

*Severe burns

*Cardiac Arrest not responding to prompt defibrillation or cardiac pacing .

*Needing large blood transfusions

*Underlying “significant and advanced” illnesses with poor prognosis and high short-term mortality (as in advanced cancer and end-stage organ failure)

MQS — Minimum Qualifications for Survival

Principles

*Place a ceiling on the amount of resources that will be allocated to any one individual.

*Early identification of patients who are not improving and are likely to have a poor outcome.

In other words — find a ‘balance’ between those who are sick enough to need the resource and will do poorly if they don’t get it, but are not so sick that they are unlikely to recover even if they do receive intensive care. In other words, every patient who is admitted to critical care should survive. [And those not admitted will surely die? Self-fulfilling prophecy.]

OPERATIONALIZING CRITICAL CARE TRIAGE

“Effective Triage depends on an established, skilled, and practiced infrastructure.”

CENTRAL TRIAGE COMMITTEE

This is a Multi-disciplinary Team:

*Making clear and transparent decisions with support from ethical and legal experts.

*Using consistent Criteria flexible enough to allow local responses.

*Primarily responsible for:

— Modifying the Protocol as the pandemic evolves – based on analysis of

[as it happens] data

— Command and Control over the critical care resources in the field.

— The key decision – when to activate the Protocol.

“These issues are too important to be decided by the individual Triage Officers in the field.”

TRIAGE OFFICERS

“The best triage decisions are made by senior physicians with training in triage and significant clinical experience.”

They must be given proper training beforehand, as well as on-going support during a pandemic.

COMMUNICATIONS

The quality of decisions by the Committee and by Triage Officers depends on the availability of accurate [up-to-date and sufficient] information. There has to be a reliable two-way Communications Network between the Field and the Committee.

[Given the current lack of effective communications and a near-total absence of reporting of system-critical information in all aspects of health care, it’s hard to believe that the Plan – which results from considerable research, intellect, and experience – will work as stated: but it is a very good start.]

POST-SCRIPT

On Tuesday, November 21, 2006, The Hamilton Spectator headline read:

“No pandemic care for elderly” as the page 1 lead-in to an article by Joanna Frketich.

On page 8 of the same issue, an article by Peter Van Harten was headed”

“Pandemic rules hard to swallow?” with the sub-head “MD predicts major ethical debate.”

I’m amazed there weren’t more such headlines, but it takes a certain amount of effort to locate and then read such things as pandemic plans, and supreme court decisions.

Does one have to be able to read as a criterion for attending journalism school? Evidently the Spectator people can, and do. I wonder about some of the others.

The debate over ethics will surely take place – if not before the pandemic, then after. As with all disasters — natural and non-natural – the political propensity to re-hash will once again raise its very ugly head.

One element (among many) in the Draft Triage Protocol Exclusion from Admission criteria set is Age > 85. So Seniors might be well advised to hide their birth certificates and lie about their age.

Triage is never easy. If a pandemic comes upon us the hard choices could become very hard. “Tennis anyone?”

Be well.

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