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For most people when they see a cam trace, it just looks like random squiggly lines. But within these squiggly lines lies a large amount of data about the baby's brain which you can use to direct management, avoid unnecessary cooling and even partially predict the neurological outcomes of the baby. Cam stands for cerebral function and analysis monitoring. It is essentially a highly simplified EEG which is capable of being interpreted by pediatricians at the bedside, identifying encephalopathy and seizure activity. I'm Doctor Matthew Sayers, a consultant, pediatrician with over 10 years experience in pediatrics. I have a special interest in epilepsy which definitely helps in my interpretation of CFA. In this video, I will share my tips on how to set up SFA M and how to interpret it. Using a number of worked examples. We are using the NAUS five lead cam set up in this video. However, the same principles apply to other S AM machines and set up links to all guidelines and documents are available in the video description and on the OA medical app. In part one of this video, we looked at criteria A and B and in this video, we will learn how to approach criteria. C criteria C requires a period of at least 30 minutes of CFM monitoring which shows e eg features in keeping with moderate or severe encephalopathy or seizure activity. We will learn how to set up and interpret the cam. Now, first prepare your equipment, you will need E eg needle electrodes, a cam machine with digital analysis box, hydrogel electrode sensors, an E eg positioning strip and a pen to mark insertion position. Firstly, you need to identify two landmarks. The tragus of the ear and the coronal suture. Start on the baby's right hand side. The tragus of the ear is the small bump in front of the ear canal shown in the diagram. The sagittal suture is the suture that runs between the anterior and posterior fontanelles on the top of the head. After identifying the landmarks, line up the E eg positioning strip with the two landmarks. The forward edge should sit just in front of the tragus of the ear and the strip should lie over the sagittal suture, adjust the positioning strip up and down. So that the same letter of the strip lines up with the position of the tragus and sagittal suture. You can see C is the most appropriate on this mannequin. Once you're happy with the position of the E eg strip, go to the area of the strip with the double headed arrows. This shows you the position of C four anteriorly and P four. Posteriorly, it can be helpful to make a mark on the baby's scalp with pen so that the needles can be inserted with the strip removed. Repeat this process on the left side by convention E eg leads on the right are always even numbers. So the corresponding leads on the left hand side are C three and P three. Insert the needles into the scalp at the positions you have marked unsheath the needles by applying gentle pressure to both sides of the plastic casing. Whilst advancing the wire and the needle will come into view carefully, insert this through the skin fairly superficially but deep enough for it to be secure. Put a small amount of gauze under the wire to protect the scalp and cover it with a clear dressing hair may need to be shaved if the wire cannot be secured. Repeat this process for the four wires in C four P, four C three and P three positions, attach the grounding lead just below the right shoulder. Insert the five wires into the appropriate input slots on the digital analysis box. When removing the needles from the scalp, take care to push a plastic sheath over the exposed needle when removing, to avoid getting a needle stick injury. Returning to our case here is the CF trace that we have obtained for this baby. You will return to it at the end of the video and you can decide if the baby meets criteria C when we are examining ac a trace, the first thing we need to remember is that the area of the blue trace represents the amount of time that the baby's brain is at this electrical amplitude, which we can measure on the y axis. This means that if there is a small area of dense blue on a sea found trace. This means that the baby's brain has little variation in amplitude. Use this knowledge to help identify the baseline, find the area of densest blue on the trace and read its amplitude on the Y axis. This represents the electrical amplitude that the baby's brain is at for the majority of the time. In this example, we can see that this is around 12 micro volts, but the exact number doesn't really matter. It's more the trend we're interested in. If we then move above and below this baseline on the Y axis, there are progressively less dense blue areas. These represent the upper and lower limits of the baseline. And this represents the amount of time in which the amplitude of the electrical activity of the baby's brain is above and below its baseline. If we move further above and below on the Y axis, again, we can see that the trace consists mainly of spikes. These are short periods outside the normal baseline. And these should not be confused with the upper and lower limits of the baseline. We will look at some examples to illustrate this further, the X axis represents time and we can examine trends and patterns in the baby's baseline and limits over the period of recording. We will now go through a series of examples showing how to interpret a trace. In this case, the upper limit is above 10. The lower limit is above five. While some spikes on the lower limit are below five, the majority of the lower limit is above five, the baseline is steady with no major increases or decreases. This is therefore a normal trace with no encephalopathy. In this trace. After an initial period of poor impedance, we can see that the upper limit is above 10. In contrast to the previous trace, the majority of the lower limit is below five. There is some shifting of the baseline between five and 10. This is a moderately abnormal trace due to the lower limit being below five. This indicates moderate encephalopathy in this trace, the upper limit is below 10. Although spikes above 10 are seen, the majority of the trace is below. The lower limit is below five. The baseline is around two micro volts with no variation. This is a severely abnormal trace due to the upper and lower limits being low and indicates severe encephalopathy. In this case, the upper limit is above 10. The lower limit is above five and the baseline regularly alters up and down in a wavelike pattern. This is a normal C A trace with sleep cycling. The changes in baseline represent the brain transitioning between the sleeping and waking states. This is frequently lost in encephalopathy. So, sleep cycling is a reassuring finding in this trace. The upper limit is below 10. The lower limit is below five and the baseline shows low activity with frequent large spikes. This is burst suppression and is a feature of severe encephalopathy. The bursts represent short periods of abnormal high amplitude brain activity with return to the low amplitude encephalopathic baseline. In this trace, the upper limit is below 10. The lower limit is below five and the baseline is low voltage with occasional small spikes. This is a flat trace. It represents very severe encephalopathy with an associated poor prognosis in this trace. The upper limit is below 10. The lower limit is below five and the baseline is low in the arrowed area. A sudden increase in the baseline is seen and on the e eg trace arrhythmic spike wave pattern is seen. This represents a single seizure in the context of severe encephalopathy. In this tracing, the upper limit is above 10, the lower limit is above five and the baseline is stable around 10. On this baseline, frequent increases in amplitude is seen with associated spike wave on E eg trace. This is frequent seizure activity without encephalopathy. The upper and lower limits are normal and the trace returns to normal baseline between seizures meaning this is not status epilepticus. In this case, it is hard to see a clear baseline, upper or lower limits as the baseline moves up and down repeatedly. The E EG shows rhythm spike wave. This is status epilepticus as there is no return to baseline between seizures. In this case, the upper limit is below 10 and the lower limit is below five. The baseline is steady and low around five in the arrow area. There is an extremely large increase in the baseline. The E EG lead shows a high amplitude rhythmical trace with no waves. This is an artifact per impedance caused by poor connection of the leads to the baby's head check. They have not become dislodged and replace it if it continues to be abnormal. Wh this trace could be confused with seizure activity. The amplitude is too high. The E EG doesn't show typical spike waves and there would be no clinical change in the baby in this trace. The upper limit is above 10. The lower limit is above five and the baseline is around 10 to 25 with good variability and sleep cycling. At the start of the trace, there is a sudden large increase in the baseline marked with an arrow and a very quick return to normal E EG trace is chaotic and doesn't show spike wave. This is movement artifact. It can be helpful if medical and nursing staff mark significant baby movements or cars to avoid confusion. When reviewing a EFA trace in this trace, the upper limit is above 10. The lower limit is above five and the baseline is steady around 7 to 8. There is a very spiky appearance to the upper limit out of keeping with the rest of the trace. And when the E EG is reviewed, there are frequent spikes at the frequency of the baby's heart rate. This is CG artifact. It can be confirmed by removing the E CG leads and the trace normalizes now that you've learned how to interpret AC A trace. Let's look at this baby's chase again, pause a video and see if you think the baby meets criteria C for cooling. In this case, we can see the upper limit is less than 10, the lower limit is less than five and this indicates severe encephalopathy. If we look again at criteria C, you can see that this baby does meet criteria for cooling. What should you do if the baby has CFM features of seizure activity but no clinical change. In the first instance, discuss this with a senior neonatologist. There is conflicting evidence on the benefits of treating electrical seizures without any clinical correlate, but some evidence that fenobarbital can cause developmental problems in babies. So it wouldn't generally be my practice to treat these but follow your local practice and the senior neonatologists decision in this scenario, how can we use CFA to predict the outcome for hie? There is good evidence that CF trace can be used to predict outcome and a normal cam trace with sleep wake cycling present at six hours and even more. So at 48 hours generally has a good prognosis. Conversely, burst suppression or flat traces. Unfortunately, generally indicates a very poor prognosis. Wh this can provide helpful information when you're speaking to parents, especially with MRI results available. Always remember that CFM and MRI cannot ever entirely predict the outcome for the child and it is only time and later development which will show if there are any learning difficulties, movement disorders or seizures associated with Hie. Thanks so much for watching. Please like this video. Comment with any clinical questions or feedback you have and subscribe to the channel and our other social media accounts including Instagram, Twitter, Med all and OLA to stay up to date with future videos. I look forward to seeing you again soon.