There are several reasons why it is important to line the PVC with a plasticiser. This is in order to reduce breakage of the bag and to increase the container’s pliability.
Effects of Plastic Blood Bags
- The plasticiser is likely to leach into the blood components stored therein
- The plasticiser may have low permeability to oxygen and carbon dioxide
- The leached plasticiser may lead to allergic reactions, reduced viability and interference with in vivo and in vitro properties of the blood components
Some plasticisers leach more into the blood components than others. For example, DEHP has been found to leach more than other forms of plasticisers.
Effects of PVC and Polyolefin Blood Bags on RBC
PVC blood bags reduces haemolysis of red blood cells while raising the ATP concentrations. Increased haemolysis of RBC reduces storage period in polyolefin bags to 6 weeks. This does not change even when a new storage solution EAS-61 is used with polyolefin bags.
Hexamoll DINCH Plasticiser and Effects on Platelets
The recommended storage period for platelets in most countries is 5 days. However, it is noted that with the use of new and improved plasticisers, the storage period can be increased to more than five days. Hexamoll DINCH is a viable alternative to conventional plasticisers in this case.
Effects of PO Bags with higher Oxygen Permeability on Platelets
Plastic bags with high permeability to oxygen improves platelets metabolism. The in vitro properties of the platelets stored in permeable bags declined less after 7 days of storage.
Carbon Dioxide Concentrations in Blood Bags and Mitochondrial Dysfunction of Platelets
The permeability of platelet bags to carbon dioxide affects the in vitro properties of the platelets during storage. Accumulation of carbon dioxide leads to pH declines, increased superoxide production and accumulation of peroxide in the bag. This leads to mitochondrial membrane depolarisation, reducing the viability of the platelets.
Effects of CLX Containers on Platelets
When platelets are stored in CLX bags for more than five days, the in vivo and in vitro properties are likely to decline. The effects on the platelets may be small, and unlikely to have significant clinical implications. But still, the effects are significant enough to attract the attention of clinicians in this field.
Surface Plasticiser Level and Fibrinogen Adsorption
Studies conducted in this field have shown that BTHC plasticiser has the lowest level of fibrinogen adsorption as compared to other plasticisers such as DEHP
Effects of Plastic Blood Bags: What is the Way Forward?
It is important to address the challenges of plastic blood bags when it comes to effect on blood components, such as platelets. More studies need to be carried out in this field to come up with better storage bags to increase storage period and in vitro as well as in vivo properties of the platelets.
Conclusion
- Most blood bags are manufactured using PVC, plasticised with various elements such as DEHP and BTHC
- The plasticiser has several effects on the blood components, such as reduced recovery of platelets
- These effects need to be addressed through e.g increased research and development in this area