Let me rephrase:
My original Statement:
My biggest mistake as a CA-1: Reversing early and letting patients SV by letting CO2 build up. This is the mother of all long/ugly wakeups.
-I never use des or N20, I hate them. Iso or sevo, most of the time Iso.
-If I Titrate opiates, I do it early. Near the start of slow skin closure (or when I think I have 10 or so minutes left), I use EtCO2 to assess how deep someone is, in that I keep it constant (32-34) as I wash out gas with agent off and high flows until they buck (I always make sure I have at least 1 good twitch). Most of the time its around a ET of 0.3ish (true reading using low flow).
-I use mech ventilation as long as possible. Only when the case truly is at the very end I reverse and switch to SV.
-Immediately get the patient in a good position, head up, suctioned.
-"Open your eyes", "squeeze my finger", pulling good TV. Extubate.
Most rookie residents think the goal is getting them to SV any means necessary. The true goal is get off as much gas as possible before extubation, especially with ISO. Here and there in I might push a some prop or fent if they get a little out of control, but this is rare because I can time it pretty precise.
I avoid this strategy for any procedure less than 2 hours or the kids/young adults (who always wake up swinging).
JWK stated that this is nonesense in a quick case. So my response was that I totally agree and that's why I originally said >2 hour case. Let me reiterate, I would NOT use this strategy in a 20 min lap chole.
So. First you say NMBDs are potentiated by acidosis, but then keeping PaCO2 low (alkalosis) will augment NMBD duration.
Bertelman was right (its a typo). Should read:
"Another thing to consider NMB are potentiated by acidosis, hypothermia, and volatiles themselves. Keeping the PaCO2 down, decreasing the gas quick (which will also raise pt temp) will help
REDUCE NMB duration. These in turns speeds up the reversal's action because of a less dense block."
Example: Recently did a 5 hour hepatic lobe resection (complicated patient with a complicated liver). Sparing the details, the patient was breathing iso near 0.8 mac balanced with liberal opiate use for 5 hours (no epidural due to orthopedic hardware). Decision was made to attempt extubation at the end of case if feasible.
As the surgeon began to close the peritoneum, my TOF=1 strong with 1 weak. At this point loaded the patient with 150 mcg of fentanyl, I dialed the gas way down to nothing and turned up the flows above MV (propofol loaded on the stop cock in case I felt the patient was getting light). Within 15 minutes Et MAC was near 0.3, EtCO2 was 34 TOF at 2 strong twitches. Turned the flow down to 1 L/min (so patient rebreathed their exhaled iso) because BIS started to creep in the 60's until they got to skin. As they stapled, I increased flow again to >MV to insure no rebreathing. TOF now at 3 strong twitches. Never took the patient off the vent Et iso mac at about 0.2. As they applied dressing, put the patient in rtberg, the patient began to start breathing over the vent at an EtCO2 of 34. Pushed reversal, suctioned mouth, switched to SV. As surgeon dictating case, I gently ask the patient to open their eyes... they do. I ask the patient to squeeze my fingers... they do. Patient pulling 500s at a rate in the teens. I do a quick clinical leak test, extubate, switch over to simple mask, move to stretcher, put HOB up, move over lines, SpO2 still 99%, out of the room within 5 minutes of last dressing applied. Never had to push propofol. Patient VAS=0, wide awake in recovery.