NHS Trust
Tips for MRCpath practical success
Loretta Ford & Jonathan Berg
Equipment you need to bring
Essential
· Lab coat (remember to do up during the exam!)
· Gloves
· Pipettes (at least 1 ml and 5 ml)
· Pipette tips
· Marker pen (for writing on consumables)
· Calculator
· Ruler
· Graph paper
Desirable
· Parafilm
· Stop clock (you will be provided with one if needed but it is always nice to have two so you can run more than one timed experiment)
· Plain 10 ml Universal Containers (these are ideal for mixing up solutions)
· Pastettes (again ideal for mixing and also if you are using a spectrophotometer recovering solutions out of cuvettes so that they can be re-analysed later)
· Thermometer
Make sure you know how to use the equipment you are bringing (if you are using a new type of pipette can you change the volume setting?)
Books and notes
You can bring any books, notes into the practical exam, but you will have little time in the exam to read them. Tietz is an obvious choice but it is also worthwhile compiling your own MRCpath practical folder. An afternoon on Google will provide plenty of ready made notes:
· Enzyme kinetics (Michealis Menton/lineweaver burk plots and how to calculate)
· Reference intervals for most analysis (especially urine tests)
· Conversion tables for units of common analytes
· Table of advantages/disadvantages of near patient testing
· Be familiar with the chemistry of ATP/NADH it nearly always shows up!
It is far easier for the examiners to get hold of enough urine for 20 student practicals than blood. A quick look at past practicals reveals most involve urine analysis. This of course limits the number of analysis that can be performed e.g. creatinine, proteins drugs, of abuse. So try to include some notes on urine analysis if you can.
Before you start……
A) Approach to the practical exam
At the front of your answer paper write a heading similar to “notes on approach to practical”. Spend 10 mins reading through to the end of the paper (examiners have a habit of adding in vital details in the last sentence that can change how you approach the practical). Underline any points you feel important, and make a note of any initial ideas you may have.
Check that you have all the reagents listed. If there are manufacturers reagents check lot numbers, use by dates and storage conditions (for example if reagents need to be warmed to room temperature and feel cold point this out!). Make a note that you have checked these points so the examiners can see this. Demonstrate topical knowledge if you can (is the device CE marked for example?)
B) Work Plan
Write a work plan. Check that you have enough reagents for the work you propose. Often only a set volume of reagents are provided and no more. Check through calculations carefully and show all working out.
Steps A and B may take as long as 30 mins. If people are starting the practical already (and there will be some) ignore them. It is better to be prepared and know what you are doing at the start than to make a simple mistake, which uses up the entire reagent you have!
Take a final few minutes to check the work you are proposing to do will answer the examiners questions!
Practical work and writing up
Make sure there is a date and the name of the investigator on the top of each page (as you would for any laboratory book)
For each experiment you will need:
· Title e.g. Aim of experiment is…….
· Reagents –list reagents to be used and any dilutions
· Methods –brief outline of method used
· Results –always present results in a tabulated form (also make a note of any important observations such as colour changes. If using manufactures strips for a NPT device and one is more difficult to use or does not perform as well as another mention this!
· Conclusions –this should also include a few lines on what your next experiment will be in light of the results
· Summary after completing all the practical work summarise all results on a single page in tabulated form
Practical tips
· Most practicals require a calibration curve, measurement of standards, patient unknown samples and investigation of interference.
· For calibration curves a minimum of 3 points is required unless stated otherwise. If a range is not provided than use the reference range quoted for the analyte in Tiets. Do not use serial dilutions to prepare calibration curves because if one dilution is out all subsequent solutions will also be out.
· Try to perform all standards and patient sample analysis in duplicate.
· Make sure axis on graphs are labelled and there is a title.
· Extra marks are obtained for initiative. If you are looking at a reaction with an end point of 10 mins continue measuring for 30 mins and record what happens.
· Investigation of near patient testing devices is a popular choice for examiners so it is worth reading up on NPT. NPT are operator dependent so you should mention in your conclusions how easy the device was to use, robustness (in a busy A&E department a device that gives the right result within only a 2 minute time frame is not much use) and clarity of results.
· Recently examiners have asked candidates to write a short report for a consultant at the end of the practical so try and practice with your supervisor beforehand. If the practical involves any NPT device and you have done some background reading this should be easy.
The report should include a heading and clearly outline the work you have carried out (with reasons why), results and conclusions for each experiment. If there are actual questions set in the practical make sure they are addressed in the summary.
· If you do make a mistake or the practical does not work say so and try to explain why!
IMPORTANT!
Remember marks can only be given for what you have written down so even if you do not think it is that significant write it down. Explain clearly everything you do, and regardless of whether you have finished all the experiments you wanted to do or not leave at least 15 mins at the end to write it all down!
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