Hazardous Area Response Teams: the clinical aspects

David Baker DM FRCA

Chemical Hazards and Poisons Division (London)

Health Protection Agency (UK)

Objectives

Introduction to Hazardous Area Response Team (HART) project

Why HART is needed

What can and should be done for casualties from chemical release

Problems in providing care

Basis and development of the HART clinical standard operating procedures (SOP)

Provision of pre - hospital emergency care – the case for a combined paramedical – medical response in HART and USAR

Toxic hazards and threats in civil life

Deliberate or accidental release of toxic chemical agents is an established hazard

Hazards may be established agents of chemical warfare (CW) or toxic industrial chemicals (TIC)

Some TIC are also CW agents

CW agents classed as part of Chemical, Biological, Radiological and Nuclear (CBRN) releasesNot an appropriate classification in terms of emergency medical responses

Properties of toxic agents

Toxicity

Latency of onset of signs and symptoms

Persistency

Transmissibility

In chemical releases toxicity and latency determine the management of the patient but persistency and transmissibility determine the management of the incident and the health risks to others

Specific Chemical Hazards

Nerve agents (eg sarin)

High toxicity, short latency, variable persistency, high transmissibility

Cyanide agents (eg hydrogen cyanide

High toxicity, short latency, limited persistency and transmissibility

Lung damaging agents (eg phosgene, methyl isocyanate)

Toxic after a variable latency period

Vesicant agents (eg mustard gas)

Relatively long latency period to clinical manifestation but early lung damage occurs in high temperatures

Somatic systemic attack by chemical agents

CNS

PNS

Autonomic

voluntary

Epithelial and cellular

Gastrointestinal

Urinary

Circulatory

Haemopoeitic

Respiratory

Control, mechanics, airways (large and small), alveoli

Decon Shower

Decon Shower

Inner

Cordon

HOTZONE

WIND

TriageSieve

CasualtiesTriageSort

A&E

Loading Point

Outer

Cordon

WARMZONE

COLDZONE

Chemical incidents: the civil Hazmat response

Chemical agent medical response realities

HAZMAT protocols confine victims to the warm zone prior to decontamination

Requirement in certain cases for early and continuing medical care before decontamination

Antidotes alone may not enough for patient support

Life support required in a contaminated zone by trained and protected personnel

Problems of working in a contaminated zone

Need for personal protection

Loss of contact with patient

Difficulties in physical examination

Normal emergency medical procedures for airway, ventilation and vascular access are all made more difficult

What care must be given in the contaminated zone?

Triage (P1 – P4)

Airway management

Artificial ventilation

Vascular access

Control of haemorrhage from associated physical injury

What primary care is feasible in the contaminated zone?

Application of skills used in normal emergency practice

Triage: primary triage sieve

Recognition of key signs and symptoms

Airway management: position, suction, airway insertion

Ventilation: use of specially designed equipment

Vascular access: intraosseous approach

Early administration of antidotes

Contaminated zone care – a Cold War view

TOXALS Protocol (1996) for advanced life support in a contaminated zone or decontamination area

Assessment (patient and site)

Airway

Breathing

Artificial ventilation

Circulatory

- control of haemorrhage and cardiac abnormalities

Disability (AVPU scale)

Drugs and antidotes

Decontamination

Evacuation

Department of Health Emergency Preparedness Division project

Two-year investigation into Hot Zone Working

Final report submitted in Jan 05Ministerial approval in Aug 05

Hazardous Area Response Teams (HART) origins

HART: Development of Standard Operating Procedures

SOP define the following and provide the bibliography for the project

Tactical Role and ResponsibilitiesHealth and Safety & Risk AssessmentTeam Structures, Concept of Operations, Objectives and Roles Vehicles & Areas of OperationPPE, Deployment Criteria Communications Clinical procedures

HART - clinical objectives

Provision of essential immediate care for chemical casualties before and during decontamination

Provision of continued care from point of chemical release to A and E and beyond – treatment protocols, decontamination, life support equipment and antidote stockpiles

To train and equip paramedical personnel to operate safely in a contaminated zone

Integration with other dangerous environment responses – urban search and rescue (USAR)

HART: the paramedic challenge

Extension of current clinical skills

Special training to operate safely inside a contaminated zone

To provide essential early life support before and during decontamination and to deliver the patient quickly to definitive hospital treatment

HART clinical sub – group

Input from specialists in:

Accident and emergency medicine

Anesthesiology

Medical Toxicology

Paramedic Training

Clinical Rationale

TriageAdvanced clinical life support with early intervention Airway and ventilation management.Infusion control of major haemorrhageAntidotes Support drug administration

Hart Clinical Subgroup: basis for warm zone treatment protocols

Findings of the DH Expert Group on the Management of Chemical Casualties Caused by Terrorist Activity (Blain Committee) report 2003

Existing JRCALC paramedic training protocols

Medical and paramedical experience

Patients in hot and warm zones: levels of care

Level 1: ambulant and asymptomatic

Level 2: ambulant and symptomatic

Level 3: non – ambulant, conscious

Level 4: Unconscious

Level 5: physically – trapped

Level 4 and 5 patients are vulnerable but salvageable and in need of expert clinical care. TOXALS essential to avoid fatality from toxic respiratory failure

Is patient able to walk? YES = P3

NO Is patient conscious? (able to obey commands)

YES = P2 NO

Signs of Life? (open airway & respiratory effort)

YES = P1* NO = P4

HART: primary toxic triage

* Unconscious patients and those with obvious signs of respiratory distress must be

prioritised for immediate assessment and emergency treatment (P1)

Point of injury/poisoning (Hot Zone)

The Casualty Collection Point (Warm Zone),

Casualty Decontamination Area

The Casualty Clearing Station

HART: provision of TOXALS and antidotes

Cold Zone(AMP)

Medical Recce:

Toxic TriageCombopen(s)Evacuation to

warm zone

Hot Zone

DecontaminationContinued Medical careABC’swith antidotes

Continued Medical careRe - triageAdvanced Medical ManagementAnd Transfer to definitive care

Warm Zone(Casualty

collection point)

Warm Zone(decontamina

tion)

Oxygen, LMAPortable gas – powered ventilators

Combo-pens,IO accessAtropine,Diazepam,Salbutamol,Dexamethasone,Dicolbalt Edetate)

Spectrum of HART Clinical Care at toxic primary Incident site

HART airway and ventilation management

Hot zone: simple positioning – lateral

Airway clearance: suction

Warm zone:

Laryngeal mask airway as desired option

ETT as alternative option

Ventilation using VR1 portable gas – powered CBRN ventilator

Oxygen from multi – outlet supply

HART: ventilation capability in a contaminated zone

Multiple outlet oxygen provision

HART: Life support logistics

HART Logistic Unit

Treatment protocols

Simple and straightforward to allow for difficulties of working in PPE in a contaminated zone.

Based upon previous DH consensus for primary treatment of chemical victims

(EXPERT GROUP ON THE MANAGEMENT OF CHEMICAL CASUALTIES CAUSED BY

TERRORIST ACTIVITY, 2003)

Patient group directions (PGDs)

Patient Group Directions (PGDs) are documents which allow medicines to be given to groups of patients - for example in a mass casualty situation - without individual prescriptions having to be written for each patient.

They empower staff other than doctors (for example paramedics and nurses) to give the medicine in question legally

UK National Reserve Stocks: 2002

POD 1

- Modesty Clothing

POD 2

- Nerve Agent antidote

POD 3

- Equipment; Ventilators etc.

POD 4

- Ciprofloxacin

POD 5

- Doxycycline

POD 4POD 4

POD 1POD 1

POD 3POD 3

Replacement of original PODS and transfer of control to ambulance services - ongoing

Strategic supplies to be placed on underground and national main line stations

Upgrading of equipment and drug scales

Drug & Equipment Pods revision 2007

2006 REVISED PODS/HART response drugs

Combopens (P2S, Atropine, Avisophone)Atropine (2mgs/ml) – 50 mlsDiazemuls (1mg/ml) – 10 mls(Amyl Nitrite ampoules)Dicobolt Edetate 300mgs ampoules50% glucose - 50mlsSalbutamol Inhalers 100ugsBeclomethasone inhalers 100ugsSalbutamol 5mgs (for nebuliser)Dexamethasone 8mgsNaloxone 400ugs Flumazanil 500ugs

Urban Search And Rescue

Emergency medical teams working alongside the Fire Service to deliver clinical support to trapped injured persons

New skills must be learned ranging from working underground, in confined spaces and working at height

Wide range of incidents in abnormal environments

USAR Clinical SOP

USAR SOP requirements different from HART

No SOP have yet been drafted

USAR clinical sub – committee not yet formed

Early consultations with clinical expertise taking place

Training to JRCALC standards before USAR training

Issues

Consensus on early management of crush syndrome

Division of crushed tissues for release

Use of chest drains

Airway management in confined spaces

Training and governance for use of ketamine and midazolam

2006 REVISED PODS/USAR response drugs

Etomidate

Suxamethonium

Ketamine

Midazolam

Morphine

Propafol

Cyclizine

Lignocaine 1%

50% glucose

The requirement for a joint paramedical medical entry team in HART and USAR

Difficult triage decisions can be taken by medical personnel on site (the question of P4 triage)

Antidotes and life support drugs can be given without the need to use patient group directions and dose protocols

Difficult airway – ventilation cases can be managed with a team approach

General anaesthesia can be given for extraction

Joint paramedical – medical emergency care

Proven value in conventional attacks

HEMS and BASICS are integrated already into EMS response in UK

Problems

No official recognition or funding of existing arrangements

Lack of co – ordinated policy and structure

HART commissioning: London, December 2006

HART clinical policy – problems identified

Training issues regarding new procedures – regional variations eg LMA

Administration of essential antidotes and support drugs (PGD)

Clinical SOP still being adjusted with user feedback

USAR clinical SOP have yet to be determined but raise questions about medical presence

Conclusions

HART project now active in London

Expansion of project to other cities projected for 2007 -8

Special skills have been taught to paramedics and technicians to enable provision of essential life support in a contaminated zone

USAR has been linked in with HART by DH EP Division

Both initiatives increase the ability of the ambulance services to respond to circumstances outside the remit of usual practice.