There is no single model for a poison centre: the location, associated services and scope of service provision can vary considerably. This section describes the most common types of model in operation in various countries (3).
2.5.1 POISONS INFORMATION CENTRE ONLY
Some centres function exclusively as poisons information centres, providing information to health care professionals and, in many cases, the general public. The staff of such centres are not actively involved in the medical management of poisoned patients and only give advice over the telephone or otherwise. Ideally, as described above, at least one medical toxicologist with clinical experience should be attached to the centre. This model is most common in low- and middle-income countries, although not exclusively, and is the easiest to set up with relatively limited resources. Although the majority of poisoning enquiries can be managed in this model, it may lack the clinical input developed through practical experience in the management of poisoned patients, which is an advantage in advising on more serious or complicated poisonings.
2.5.2 POISONS INFORMATION CENTRE ATTACHED TO A CLINICAL UNIT
Another model of a poison centre provides both information and a clinical service. In these centres, medical staff are involved in clinical management of poisoned patients. These poison centres are usually located within a hospital. The centre may have a dedicated treatment unit, or physicians at the poison centre may have allocated beds in the hospital to which poisoned patients can be admitted. Alternatively, the medical staff of the poison centre may jointly manage patients admitted to hospital departments such as a paediatric unit, emergency department or intensive care unit.
This model provides the opportunity for poison centre medical staff to gain direct experience in the management of poisoning, sharing evaluation of cases with other specialists and maintaining general clinical skills. The clinical expertise thus acquired is the basis for the advice given to physicians who consult the poisons information centre about complicated or serious poisoning cases. This model also provides the opportunity for research on the management of poisoning.
2.5.3 POISONS INFORMATION CENTRE ASSOCIATED WITH AN ANALYTICAL TOXICOLOGY LABORATORY
A further model is one in which the poisons information centre has, or is closely linked to, an analytical toxicology laboratory in which samples from poisoned patients can be analysed. Information is provided by dedicated trained staff, and there is the opportunity for sharing knowledge and experience with laboratory staff on the types of analyses that should be offered and interpretation of the results of toxicological analyses.
2.5.4 POISONS INFORMATION CENTRE THAT PROVIDES INFORMATION, ANALYTICAL TOXICOLOGY AND TREATMENT
Some poison centres provide a comprehensive service for the management of poisoned patients, with dedicated, integrated units providing information and clinical advice, clinical management of poisoned patients and an analytical toxicology service. This model is less common, but it offers good opportunities for training and research.
The laboratory usually specializes in toxicological analyses and may therefore provide services at district, regional or national level.
2.5.5 COMBINED POISON AND MEDICINES AND/OR TERATOLOGY INFORMATION SERVICE
A relatively common model for poison centres is a combined medicines and poisons information service staffed by pharmacists. Such a service may start with medicines information then extend its scope to cover poisoning to fill a gap. A variation is inclusion of therapeutic drug monitoring in addition to the medicines and poisons information service. Such centres are usually overseen by a pharmacist with specialist toxicology training or knowledge. Some centres may also include a teratology information service to advise on exposures during pregnancy.
2.5.6 CROSS-BORDER POISONS INFORMATION SERVICES AND POISON CENTRE NETWORKS
Most poisons information centres offer a service in a single country, but there are a few cross-border poisons information services. One example is the National Poisons Information Centre in Dublin, Ireland, where out-of- hours service is provided by the United Kingdom NPIS (4). The two services use the same databases for providing toxicological advice and recording enquiry data, which ensures a consistent approach to poisons information enquiries.
A cross-border toxicological consultancy system has been established by an Italian poison centre with industry support for the management of poisonings and chemical accidents in countries where there are large Italian industrial installations but no national poisons information centres. The system is based on telemedicine techniques and on targeted preparation of local health services, for example through provision of standard operating procedures, toxicological evaluations for occupational health services and an antidote supply.2
Short-term cross-border arrangements have also been made. For example, the London Centre of the NPIS handled overnight telephone enquiries to the New Zealand National Poisons Centre for 4 months to cover a staffing shortfall (5).
In preparation for this partnership, the New Zealand Centre provided the London Centre with New Zealand medicine formularies, pharmaceutical schedules, medicines guides, access to the New Zealand Internet-based poisons database TOXINZ and the contact details for New Zealand hospitals. The London Centre completed reports for all New Zealand calls and sent them to the New Zealand Centre daily for auditing and medico-legal purposes. In another example, the poison centre in Lille, France, works with the Belgian Poisons Information Centre to coordinate antidote supplies. The two poison centres also have an arrangement to transfer telephone enquiries to the other centre in case of service discontinuity, due for instance to an IT failure, fire, natural disaster or terrorist attack.3 Most poison centres also handle a small number of ad-hoc enquiries from other countries. For example, during the 4-year period 1 June 2015 to 14 May 2019, the Poisons Information Helpline of the Western Cape, South Africa, answered 199 calls from other countries, accounting for 0.5% of their total calls.4 Most of the calls (28%) were from a neighbouring country, but calls were also taken from 10 other African countries.
Poison centres may also take a few calls from overseas nationals, for example, from the armed forces or clinicians working abroad where a local poisons information centre is not available.
2 C. Locatelli, personal communication, January 2019
3 M. Mathieu-Nolf, personal communication, July 2019
4 C. Marks, personal communication, July 2019
The possibility of a sub-regional poison centre in East Africa that would serve several countries was examined in a feasibility study led by WHO in 2014 (3). Various options were examined, for example, a sub-regional centre that belonged to one country and offered services to other countries on a contractual basis or an international centre hosted by one country and run by an international steering group. Some requirements to ensure that a cross- border service is operational were identified (Box 2).
Box 2. Requirements for a sub-regional poisons information centre (3)
1. The sub-regional poisons information centre should serve countries with a common language in order to maximize accessibility.
2. There should be good telecommunications infrastructure linking the countries to the poison centre.
3. There should be strong political support and an institutional and legal framework agreed by the ministries of health, environment, finance, trade and justice of all the countries concerned. This framework should cover issues such as funding for the service, the scope of the service and its terms of use (e.g. who can use the service, response times, quality standards and procedures for alerting about chemical events).
4. There should be agreement on how issues of accountability and medical liability would be handled, and, ideally, there should be harmonized legislation between the countries on such issues.
5. There should be agreement on the handling of confidential information such as patient data and commercially sensitive information on products.
6. The sub-regional centre should have collections of information about the pharmaceuticals, products, plants and venomous animals in each of the countries that the centre serves, including local names.
7. The centre should have information on clinical and laboratory services in the other countries and, if available, the contact details of specialist toxicologists in the countries served.
Potential obstacles and disadvantages in setting up a sub-regional poisons information service were also identified (3), including:
• difficulty in allocating responsibility for procuring funding (both to establish the centre and for maintenance);
• language barriers between countries;
• significant administrative overheads to ensure that all user countries paid their share for the service;
• political instability in the host country, which could threaten continuation of the sub-regional service;
• potential unwillingness to share information about poisoning events, patients and products;
• regulations and laws relating to standards of medical care, confidentiality and liability that could create medico-legal barriers;
• reduced accessibility by all rural communities to a single sub-regional poison centre; and
• more benefit to the host country in professional training and toxicological experience than to other countries.
These considerations are likely to apply to other regions or sub-regions.