Cold chain management for thermo-sensitive product

The cold chain is a system intended to keep thermosensitive medical products, within a specific temperature range from the manufacturer until its final use. In MSF settings, the “cold chain” means keeping medical products between +2°C and +8°C (inclusive). Temperature deviations can lead to cold chain ruptures, compromising the quality of therapeutic and diagnostic products and on occasions leading to their destruction, costing time and money.

In MSF, cold chain items can be divided into three main groups:

• Immunization products (vaccines)
• Therapeutic products (e.g. immunoglobulins, insulin or oxytocin)
• Diagnostic products (e.g. blood grouping reagents).

The EU, WHO GDP (guidelines for good distribution practices) for pharmaceutical products, as well as the different national regulations, requires a focus on ensuring proper environmental conditions (as per manufacturer label claim) during storage and transportation.

In the medical catalogues and on the order lists, all thermo-sensitive products are associated to a thermosensitive code listed in the table below.

The products that do not require a temperature control have no thermosensitive code associated.

STORAGE INDICATIONS

A pharmaceutical product, if not stored according to manufacturer’s specifications, might become ineffective or dangerous for the patient.

Controlled Temperature: 2°C-30°C

The storage and transportation of medical items falling into this thermosensitive classification needs to be done in compliance to the Good Storage and Distribution Practices. In the medical storage facilities, the temperature should be monitored and recorded twice a day in a dedicated sheet.

Example of items stored between 2°-30°C: Specialised Food items (NFOS), medical devices of class I and IIa.

Controlled Temperature: 2°C-25°C

The storage and transportation of medical items falling into this thermosensitive classification needs to be done in compliance to the Good Storage and Distribution Practices. In the medical storage facilities, the temperature should be monitored and recorded twice a day in a dedicated sheet.

Example of items stored between 2°-25°C: some Specialised Food items (NFOS), dressings (SDRE), sampling and transport mediums and containers (STSS), medical devices of class IIb and III.

Controlled Room Temperature 15°C-25°C

The storage and transportation of medical items falling into this thermosensitive classification needs to be done in compliance to the Good Storage and Distribution Practices, following the requirements expressed by the World Health Organization and the national drug regulatory authorities (NRAs). The premises and vehicles used for storing or transporting medical products, should be of a suitable size and of a standard that allows for a secure, clean and temperature-controlled storage with a relative humidity below 65 % and no direct sunlight affecting the products. Temperature and relative humidity should be monitored and recorded twice a day in a dedicated sheet, the tool recommended for this purpose is the following: PCOLMONIHLU - THERMO-HYGROMETER recorder (Log Tag Uhado-16) display.

Example of items stored between 15°-25°C: medicines (DORA, DINJ, DINF, DEXT, DEXO), some dressings (SDRE), laboratory reagents (SLAS).

Cold Chain / Refrigerated 2°C-8°C

The transport of items falling in this thermosensitive classification needs to be done in isothermal containers, while the storage requires ice-lined refrigerators (see storage and transportation equipment). Temperature should be monitored and recorded twice a day in a dedicated sheet, with monitoring by FreezeTag and LogTag (see cold chain management).

Example of items stored between 2°-8°C: most of the vaccines (DVAC), some rapid diagnostic tests (SDDT), laboratory tests and controls (ELAE).

Frozen -20°C

The transport of items falling in this thermosensitive classification needs to be done in isothermal containers with dry ice. The storage requires qualified freezers. Temperature should be monitored and recorded twice a day in a dedicated sheet, with monitoring by the PCOLTHER35A - THERMOMETER alcohol (Moëller 104614) -30°C-+50C° (to be kept vertically).

Example of items stored at -20°C: a few laboratory tests and controls (ELAE), a couple of laboratory reagents (SLAS) and antibiotic powder for antibiotic susceptibility testing (SAST).

STORAGE AND TRANSPORT EQUIPMENT

Cold chain equipment is divided into two main groups:

The active cold chain category includes all equipment that require energy to produce and maintain the cold. This kind of equipment is mainly used for the items storage or icepacks production. Under this category we have:

• Fridges
• Freezers
• Cold rooms

The passive cold chain category includes the equipment which, in order to maintain the cold, requires pre-conditioned ice-packs. Under this category we have:

• Isothermal/cold boxes
• Vaccine's carriers
• Icepacks

Selection Criteria

The cold chain equipment must meet the needs of each medical activity, as defined by the medical program with specific regards to storage volume and the icepack production capacity required.

The choice of equipment must meet the following criteria:

WHO Pre-Qualification

The WHO “Performance, Quality and Safety” (PQS) process prequalifies products and devices so that member states and UN purchasing agencies are assured of their suitability for use in immunization programs. Similar to vaccine products, MSF recommends using WHO pre-qualified equipment for cold chain activities because of its reliability standards. The updated list can be found at: https://apps.who.int/immunization_standards/vaccine_quality/pqs_catalogue/.

Storage volume

For fridges, freezers and cold rooms, the net volume (expressed in litres) indicates the maximum quantity of medical items that the appliance may contain using the storage baskets (or shelves in the case of a cold room). The gross value is the overall volume without the baskets or the shelves. When estimating the storage needs it is crucial to consider the net volume and not the gross volume. The medical activity determines the equipment’s net volume required based on the kind and quantity of products to be stored (per Medical Standard List).

Ice Pack Production

The Medical Activity defines the needs for passive cold chain. The passive chain will require a quantity of ice packs per day to be sustained (at various locations). Combining the ice pack volume (0.4 or 0.6 L) and the quantity of each ice pack needed by the medical activity, the total freezing capacity (in kg/24 hours) can be determined and therefore the correct equipment selected.

Key Equipment Parameters

Storage Volume

For fridges, freezers and cold rooms, the net volume (expressed in litres) indicates the maximum quantity of medical items that the appliance may contain using the storage baskets (or shelves in the case of a cold room). The gross value is the overall volume without the baskets or the shelves. For isothermal/cold boxes and vaccines carriers the storage capacity indicated is normally always the net one (excluding the space occupied by icepacks).

Holdover time

The standard MSF active cold chain equipment has the characteristic of guaranteeing, in the absence of its energy source, that the temperature is kept within range for a period of time (thanks to thermal insulation, Ice-Lining, etc). This cold time extending characteristic is called “holdover time”, and is measured in hours. The holdover time changes according to the equipment brand and model. The holdover time is always specified within an environmental temperature range (e.g. 02-08°C maintained for 48 hours if external temperature is between 15°C and 43°C).

Cold Life

Refers to passive cold chain equipment. Is intended as the time (in hours) that the equipment can keep the medical products between a specific range (e.g. between +2°C and +8°C). The cold life parameter is also only reliable within a specific external temperature range for which the equipment has been qualified.

Freezing capacity

Specific for the freezer equipment, it is the capacity of a specific appliance to produce a certain volume of ice in a specific interval of time. The units of measure are indicated in kg/24 hours.

Special Considerations for equipment type selection

Solar models

New solar refrigerator models with or without battery (direct drive) are included in this catalogue. There are many different models and some have certain constraints on their use (maximum ambient temperatures or other logistical/context constraints).

Solar refrigerators are generally up to 5 times more expensive than the equivalent mains powered versions. Therefore they should only be chosen for locations where no electricity is available.

Blood bank and biological sample equipment

Blood bank refrigerators and other specialised refrigeration or storage equipment are considered as medical equipment. For technical support on this type of equipment contact your technical support for Biomed.

Domestic refrigerator models

The use of domestic refrigerators to store thermo-sensitive pharmaceutical products is not recommended for the following reasons:

• lighter insulation
• imprecise temperature regulation
• internal temperature variation
• temperature changes as a result of automatic defrosting
• difficulty of locating the cold and warm zones because of the diversity of models and technologies.

TEMPERATURE MONITORING DEVICES

Temperature monitors are important tools to ensure that thermo-sensitive products are kept at the correct temperature range. There are several types of temperature monitors:

• non-reversible monitors: single use tools, once the alarm is triggered it will have to be replaced
• Temperature recorders: tools with memory storage that sense temperature at specific intervals; that can be reset and reused; that include an alarm. Data and alarm parameters are programmable per OC specifications. The sensing calibration is valid for the life of the original battery.
• Remote temperature recorder: tools that send the actual temperatures to a cloud system for remote visualisation and analysis; they also include alarm settings. Alarm notifications can be send via e-mail or SMS.

Knowing the recommended use of monitoring devices assists with calculating quantities needed:

GENERAL RECOMMENDATIONS FOR COLD CHAIN MANAGEMENT

Evaluation of needs for a new activity

• What is the nature of your activities (laboratory, hospital, routine vaccination, vaccination campaign, outpatient department...)?
• What storage capacity do you need? The volume of vaccines for example varies according to the product, the presentation and the manufacturer.
• Define your storage needs in collaboration with your pharmacist
• To find out the volumes of thermo-sensitive products, refer to the guidelines (Measles guidelines, Meningitis guidelines) and/or contact your supply centre
• How much freezing capacity and storage capacity do you need for the ice packs?
• How many cold-boxes, vaccine carriers and ice packs do you need?
• Which monitoring tools should be ordered?

Assessing the existing cold chain capacity

• Is the quality of the cold chain satisfactory?
• Does the equipment fit your needs in terms of capacity and performance?
• Is the equipment in good working order?
• How reliable is your electricity supply?
• Is the equipment permanently accessible?
• Are refrigerators and freezers located in a cool, clean place?
• Do they have enough capacity to store all the temperature-sensitive products and to freeze ice packs?
• Is the monitoring equipment complete and functional in each refrigerator or freezer?
• Are the monitoring procedures for temperature-sensitive products on arrival and on departure well defined?
• Are the temperature cards properly filled out twice a day?

Contingency plan equipment requirements

• Provide enough passive cold chain equipment (accessible, in good condition) or spare fridges to store the more sensitive products
• Ensure frozen icepacks in a sufficient quantity and their renewal (corresponding to the number and the type of cold box)
• In case of cold chain breakdown, follow your OC specific cold chain indications.
• Distribute the responsibilities of who does what and make sure everyone is properly trained.
• Take contingency plan into account when estimating needs and placing equipment orders.

Transportation Recommendations for Cold Chain Items

• The shipment receiver has to check their storage capacity before green lighting an order of cold chain items. Preclearance or any possible administrative paperwork is completed in advance to avoid transit delays (that are linked to packing cold life).
• The first choice of transport between central and periphery stocks for cold chain items should be by air freight when available.
• In case of road transportation, choose the fastest option, match packing cold life with anticipated delivery times and avoid open vehicles.
• The packaging container should be chosen depending on the type of transport, the lead-time and the means of transport.
• Prior to any shipment, the sender should confirm the volume, date and time of arrival of a cold chain shipment (to ensure adequate storage space upon arrival).

Freezing Prevention while using passive cold chain equipment

• Use only ice packs filled with water! Ice packs pre-filled with coloured refrigerant gel are not suitable since they have a freezing point below 0 ºC
• Always make sure your ice packs are conditioned at 0 ºC, before placing them in the cold-box
• Follow your OC- or mission-specific procedure on conditioning of the ice packs
• Place cardboard between the temperature-sensitive products and the ice packs to prevent them touching
• Always control the temperature inside your cold boxes, before introducing the products

Other Recommendations

• PCOL equipment is not meant for storing or transporting food, blood or biological samples.
• Define written procedures for the transport of thermo-sensitive products (preparation, monitoring tools, labelling and shipping documents) in coherence with HQ recommendations.
• Contact OC Cold Chain Technical Advisor if there are any doubts
• Consult your technical department before ordering cold chain equipment that is not MSF standard.
• For any order of non-standard spare parts, please mention the type and the serial number of the appliance concerned and if possible the reference number of the part to be replaced.
• In case importation (or other) constraints do not allow the procurement of MSF standard equipment, the purchase of any alternative device must be done only after the validation of the OC referent.
• When performing a market assessment, it is recommended to assess the availability of WHO prequalified equipment[1] or specifically certified devices (for the storage of medical items).

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