mobey Posted January 18, 2012 Author Posted January 18, 2012 Hence why you should inflate with a 10cc syringe. I think this may be the exact problem! No matter what the adult airway size, no matter what the tube size, it seems we arbitrarily throw 10ml into the cuff without thought. We really should be using pressure guages in this circumstance, especially with extended transport times. BUT a question for you positive pressure ventilation, did you increase or decrease his mean airway pressure from the set CPAP numbers ? hmmmm Well.... Let me think aloud. Vocal cords = 5mmhg CPAP = 10mmhg (boussignac discussion aside) Total pre intubation = 15mmHg. Post intubation Et Tube = 1-2? (I dunno..... not much.... ) BVM with no diverter = 0.5-1 ? (again... dunno really) So the answer is, dramatically less! Although, I will say prior to paralytic use, he was breath stacking pretty good so that counts a little!
tniuqs Posted January 18, 2012 Posted January 18, 2012 MOV aka "minimal occluding volume" stethoscope over trachea, then a positive pressure breath slowly increasing cuff pressure. until the leak goes away on inspiration.
mobey Posted January 18, 2012 Author Posted January 18, 2012 * I know none of us like to remove functioning ETTs, especially in patient as sick as this. Any thoughts about using a Bougie introducer as a tube exchanger, or is this too cumbersome / risky? Great point Sys. I did not specify, but I would never try it without a tube exchanger. Even with that.... I was too chicken at the time
systemet Posted January 18, 2012 Posted January 18, 2012 (edited) Great point Sys. I did not specify, but I would never try it without a tube exchanger. Even with that.... I was too chicken at the time I think this was probably a good decision. I was just interested to hear if anyone had any opinions about using the Bougie this way. Got to add -- I think it's great that you're using this resource to debrief some calls, and get some constructive feedback. It's also a nice way for the rest of us to learn from your experiences as well. This is a great attitude. Much appreciated. Edited January 18, 2012 by systemet 1
mobey Posted January 18, 2012 Author Posted January 18, 2012 Interesting snippet: (dunno why these always underline) Measured cuff pressures averaged 35.3(21.6)cmH2O. Only 27% of the patients had measured pressures within the recommended range of 20–30 cmH2O. Fifty percent of the values exceeded 30 cmH2O, and 27% of the measured pressures exceeded 40 cmH2O. Thus, 23% of the measured cuff pressures were less than 20 mmHg. Measured cuff volume averaged 4.4 ± 1.8 ml .http://www.biomedcentral.com/1471-2253/4/8 Perhaps our "standard" 10ml needs revisited. How much does a manometer cost anyway? Got to add -- I think it's great that you're using this resource to debrief some calls, and get some constructive feedback. It's also a nice way for the rest of us to learn from your experiences as well. This is a great attitude. Much appreciated. Ya, I am the only medic out here, so this is the best credible resource I have found to critique calls. 1
tniuqs Posted January 18, 2012 Posted January 18, 2012 Well.... Let me think aloud. Vocal cords = 5mmhg CPAP = 10mmhg (boussignac discussion aside) Total pre intubation = 15mmHg. Post intubation Et Tube = 1-2? (I dunno..... not much.... ) BVM with no diverter = 0.5-1 ? (again... dunno really) So the answer is, dramatically less! Although, I will say prior to paralytic use, he was breath stacking pretty good so that counts a little! Do you know how to calculate Mean Airway Pressure in PPV, ah my first guess is no but thanks for playing ... so what was your RR, your Ti, Te, PIP and VT, and MV ? ps I use the little MAP microprocessor LED readout on a real ventilator. Couple of quick questions: * How long does it take for an overinflated cuff to cause tracheal injury? Depends on the pressure, impeding arterial flow (not long) or venous flow or capillary flow ? Bonus Question what artery provides blood to the trachea and if it erodes (more due to Trachoestomys) so how do you repair it ? * Is it acceptable to simply deflate the cuff until we can auscultate cuff leak or see the end of the capnograph drop off, then pump air in until it goes away, or is there a better method for doing this? see MOV, you take the risk of allowing pooled secretions between cuff and cords to scoot deeper in trachea .. capnography way to late a sign .. assure your doing a positive pressure breath to force secretions out with the airflow. * I know none of us like to remove functioning ETTs, especially in patient as sick as this. Any thoughts about using a Bougie introducer as a tube exchanger, or is this too cumbersome / risky? I think that's a great option.. we used cooks introducer's in ICU many times long term ETT gets really gucky on the end and can plug out ... that sucks big time . Interesting snippet: (dunno why these always underline) Measured cuff pressures averaged 35.3(21.6)cmH2O. Only 27% of the patients had measured pressures within the recommended range of 20–30 cmH2O. Fifty percent of the values exceeded 30 cmH2O, and 27% of the measured pressures exceeded 40 cmH2O. Thus, 23% of the measured cuff pressures were less than 20 mmHg. Measured cuff volume averaged 4.4 ± 1.8 ml .http://www.biomedcentral.com/1471-2253/4/8 <cough> this was an in hospital study ... what if your PIP is 40 cm H20 do you keep your 20 to 30 cmh20 of cuff pressure, so are you ventilating effectively with a closed system ?
mobey Posted January 18, 2012 Author Posted January 18, 2012 Do you know how to calculate Mean Airway Pressure in PPV, ah my first guess is no but thanks for playing ... so what was your RR, your Ti, Te, PIP and VT, and MV ? ps I use the little MAP microprocessor LED readout on a real ventilator. With a BVM nothing is static, it is prolly impossible to calculate! Besides.... I treat the patient not the machines (baaahahaha) <cough> this was an in hospital study ... what if your PIP is 40 cm H20 do you keep your 20 to 30 cmh20 of cuff pressure, so are you ventilating effectively with a closed system ? Everytime I think I have hit a homerun, you grab it in outfield. Gonna quit this game soon J/K
tniuqs Posted January 18, 2012 Posted January 18, 2012 You did hit a home run ... besides I love busting your balls ... hey when are you dropping in for CXRay in service ... ? Still awaiting systemet to answer the question posed ... te he. 1
mobey Posted January 19, 2012 Author Posted January 19, 2012 ... hey when are you dropping in for CXRay in service ... ? Ahh, you have not forgotten! Stay tuned...
systemet Posted January 19, 2012 Posted January 19, 2012 Bonus Question what artery provides blood to the trachea and if it erodes (more due to Trachoestomys) so how do you repair it ? (i) Inferior thyroid artery. But, other vessels including the common carotids, innomate, and the um... aortic arch! lie close to the trachea, and either the cuff or tip of the tracheostomy/ETT can erode into these vessels. (scarey case report of a fatal tracheo-innomate fistula here:- http://www.anesthesia-analgesia.org/content/88/4/777.full) Then, of course, it can erode posteriorly into the esophagus, which could be disastrous as well. (ii) Prehospitally? With a TEF, deflate the balloon, advance the ET tube to below the fistula, reinflate, cross fingers. With a fistula involving major vascular structures... I think you would have to consider how rapid the hemorrhage is occuring and how much it's interfering with ventilation and oxygenation. Unless they're getting really hypoxic / incredibly hypercapnic, I thinkit might be best to do nothing. Deflating the cuff risks removing a potentially tamponading effect, and inflating it to increase the tamponade risks further eroding the vessel and turning a sentinel bleed into an end-of-life event. If you're getting bright red blood up the tube, it's probably too late, but we could try placing the tube more distally (with some thought to the fact that it may be the tip that's eroded. In either case, it's possible we're losing large amounts of blood into the mediastinium. Transexanamic acid? Inhospital? Some sort of ninja surgical repair grafting the injured vessel? Sorry for the delay. I had to do a little continuing education to answer this one! 1
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