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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
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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) releases • Not 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
Outer Cordon Chemical incidents: the civil Hazmat response A&E WIND Loading Point Inner Cordon Decon Shower Triage Sieve Triage Sort Casualties Decon Shower HOT ZONE WARM ZONE COLD ZONE
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
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
Hazardous Area Response Teams (HART) origins Department of Health Emergency Preparedness Division project Two-year investigation into Hot Zone Working Final report submitted in Jan 05 Ministerial approval in Aug 05
HART: Development of Standard Operating Procedures SOP define the following and provide the bibliography for the project Tactical Role and Responsibilities Health and Safety & Risk Assessment Team Structures, Concept of Operations, Objectives and Roles Vehicles & Areas of Operation PPE, 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 Triage Advanced clinical life support with early intervention Airway and ventilation management. Infusion control of major haemorrhage Antidotes 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
HART: primary toxic triage 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 *Unconscious patients and those with obvious signs of respiratory distress must be prioritised for immediate assessment and emergency treatment (P1)
HART: provision of TOXALS and antidotes Point of injury/poisoning (Hot Zone) The Casualty Collection Point (Warm Zone) , Casualty Decontamination Area The Casualty Clearing Station
Warm Zone (Casualty collection point) Cold Zone (AMP) Warm Zone (decontamination) Hot Zone Oxygen, LMA Portable gas – powered ventilators Combo-pens, IO access Atropine, Diazepam, Salbutamol, Dexamethasone, Dicolbalt Edetate) Decontamination Continued Medical care ABC’s with antidotes Continued Medical care Re - triage Advanced Medical Management And Transfer to definitive care Medical Recce: Toxic Triage Combopen(s) Evacuation to warm zone 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
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 1 POD 4 POD 3
Drug & Equipment Pods revision 2007 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
2006 REVISED PODS/HART response drugs Combopens (P2S, Atropine, Avisophone) Atropine (2mgs/ml) – 50 mls Diazemuls (1mg/ml) – 10 mls (Amyl Nitrite ampoules) Dicobolt Edetate 300mgs ampoules 50% glucose - 50mls Salbutamol Inhalers 100ugs Beclomethasone inhalers 100ugs Salbutamol 5mgs (for nebuliser) Dexamethasone 8mgs Naloxone 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 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.