Nursing units usually have a main store room and secondary store rooms close to the units. The secondary store rooms can be different types, such as mobile carts or stationary storage units in patient rooms. In addition, certain supplies known as non-stick items, are not stored in central stores, but being delivered to a certain storing unit. Other supplies such as food items or surgical instruments ,must be processed (cooked, cleaned, sterilized), before going through. After use part of the supplies must go through reverse logistics and other part must go to waste management process. 

Due to the complexity of the supply chain, hospitals seek to find solutions for unique situations, in order to optimize the process and reduce costs. \cite{Landry_2013} (to be continued)

Kwon et al.\cite{Kwon_2016}analyses strategic ares where healthcare supply chain may enhance efficiency in terms of cost per patient discharge, meanwhile  improving the quality of care in terms of reducing re-admission rate.  Authors argue that fundamentals of supply chain principles should be deployed to create “supply chain community surplus” where resources can be tapped to improve quality of care. They explore three strategic areas to maximize the provider's revenue which are  understanding of supply chain principles, process improvement and deployment of logistics tools. From the variety of commercial supply chain tools authors emphasize three of them as pertinent to healthcare supply chain optimizations target  which are  reducing operating costs and improving patient quality cares including supplier relationship management, logistics tools and process improvement. According to the paper, there is a misunderstanding, that hospital supply chain is  different from the rest, and the full benefits will be realized, as soon as hospital supply chain professionals accept that the supply chain fundamentals are the same regardless in which area we are deploying supply chain tools. Because of this misunderstanding, some of the commercial supply chain tools are ignored and are not used in hospital supply chain. Authors suggest, that there is a need of new professionals with different point of view, to explore the full potential of the supply chain implementation techniques in healthcare supply chain management.  

Vries and Huijsman \cite{de_Vries_2011} try to find some parallels between industrial sector and healthcare supply chain management. The approach is qualitative based on the analysis of existing literature.  As a result of classification of existing research, five main research areas with respect to Supply Chain Management in a health care setting are defined.    Authors state that current research in the field of health care supply chain is conducted on different levels  reaching from internal supply chains to a network level. In the dynamic level research are analysed the single relationship between supplier and health care provider in the case of physical products or two health care organizations in the case of patient flows. Meanwhile, research on the chain level discusses issues related to exchange processes  taking place in specific parts of the supply chain ranging from the supplier of the supplier to the customer of the customer. A third main stream research area concentrates on the network of service providers and the exchange processes taking place between the stakeholders in this network.   A specific case, which needs to be addressed is the distinction between patient flows and supply chains related to physical goods and products. Healthcare supply chain management differs from industrial one in terms of 'assets'. Based on their analysis, authors conclude, that there are at least five main research areas, that needs to be addressed which are presented as follows:

1. What role and technology play  supporting the management and control of supply chain practices. Additionally, the enablers and barriers need to be analysed  when implementing information technology in a health service context .

2.  Some importance should be given to analyse  the influence of different stakeholders on establishing supply chain management relationships both within as well as between different health service providers.

3. More research needed to understand the strengths and weaknesses of management philosophies like lean and agile manufacturing, business process management and Lean Six Sigma in the context of health services. Many of these philosophies are often used together with supply chain management practices. However, it is not known, how healthcare organizations can benefit from the implementation of these practices.

4.Performance metrics and the results being achieved by health care organisations when implementing supply chain practices needs more attention in research. Performance measures in health care settings seems to be more complicated compared to industrial companies due to the complexity of concepts such as 'quality of care' etc. There seems to be a general consensus about the added value supply chain management practices can have for health care organisations. Making this added value more explicit by performance metrics as well as the conditions under which this added value emerges without doubt is one of the main challenges research on supply chain management in a health service context is facing.

5. Applying supply chain management concepts to patient flows requires special attention to the specifics of services. Being inseparable multiactor delivery processes in which the patient himself participates as both object and co-creator in the interaction with various healthcare professionals (customer-supplier duality) supply chain management in a service setting is far from simple. New developed concepts of disease management for chronic diseases show that supply chains get longer with combinations of different care providers in which the patient himself often is in the lead.  

In their recent work Bon and Ng\cite{Bon_2017}conducted a case study in  University Health Centre   to collect historical demand data of Panadol 650mg for 68 months (from January 2009 until August 2014). The aim of the research was to optimize the overall inventory demand based on qualitative time series forecasting techniques.