c-mac

Karl Storz video laryngoscope
Interchangeable blade system with screen recording to SD card
Flexible nasendoscope component for airway assessment
Hyperangulated “D-blade” for trauma intubations, anterior larynx, decreased mouth opening

Select the size 3 or size 4 Mac blade for the typical adult intubation
Take care plugging the blade handle onto the cable block - damage to components has occurred
Switch screen on using power button
May choose to run the device off battery to avoid tangle of cables around bed-head
Double check that the handle and cord reaches smoothly to the patient's mouth
Position screen so it can be seen be scribe, team leader, and airway doctor

For DIRECT LARYNGOSCOPY the screen should not be used by the intubating registrar
Face the screen AWAY from the intubating registrar
Teach epiglottoscopy and tube delivery in the standard fashion (Richard Levitan principles)
Supervising consultant can fine-tune the registrar's technique by using the on-screen image
For INDIRECT LARYNGOSCOPY (ie VIDEO ASSISTED) a 4 step technique is advised
- 1- look at the patient's mouth as the tip of the laryngoscope blade is gently inserted and advanced
- 2- look at the screen as the position of the camera is optimised for a view of the glottis
- 3- look at the patient's mouth as the tube or bougie is inserted
- 4- look at the screen as the tube or bougie is advanced (delivered) between the vocal cords
- NOTE that the TARGET (ie the vocal cords) should be towards the TOP of the screen rather than the centre, to allow a better view of the pharynx and the movement of the tube or bougie as it is delivered

Flat battery: this will result if the CMAC is not returned to the wall outlet for charging between patients
Auto Screen Off: the time-out is set to 10 minutes so ensure that the C-MAC is off until the last 3 minutes before intubating
Screen upside down: as the screen can rotate on its mount ensure that its orientation is correct
Screen lock: occasionally the software will crash and will not respond to power-off; if this occurs re-set the device by inserting a drawing up blunt needle into the reset button port next to the SD card slot
Tangle of cables: take care to check the position of all leads and cables prior to induction of anaesthesia

Opinion differs as to the way the C-MAC should be used in ED
Some consultants use it routinely, others reserve it for use if standard direct laryngoscopy fails
Intubating registrars must recognise that the D-blade requires a different technique for tube delivery and that it is advised to practice this on the Truman mannequin prior to a clinical encounter