LipidRescue™ Resuscitation

I was medically directing the anesthetic for an excision of a wrist ganglion under Bier block. The Bier block was performed by a student anesthetist who was being supervised by a CRNA. The student was asked to prepare a syringe of 0.5% lidocaine, 50 mls, for the Bier block. A double tourniquet was placed on the upper arm and inflated to 250 mmHg after exsanguination with an Esmarch. The patient's BP prior to tourniquet inflation was 146/80. At this point, the patient had already been sedated with midazolam, 2 mg, and propofol was being continuously infused. The 50 mls of local anesthetic was injected without incident, and I left the room while the arm was prepped and draped. Approximately 15 min. after the injection, I was informed by the CRNA that the student had mistakenly drawn up 0.5% bupivacaine instead of 0.5% lidocaine and that bupivacaine was what had been injected. Up to this point the patient had maintained a syst BP of 100- 110 and HR 62-64. Then, 26 min after injection, the HR dropped to 35 with a slight drop in BP to the mid 80's. The patient was assumed to be sedated since the propofol was still infusing. The ECG showed sinus bradycardia without changes in QRS morphology. The propofol was stopped. Atropine, 0.4mg followed immediately by epinephrine, 200 mcgm was given. Then 20% Intralipid in 2 boluses of 60 ml each was given in rapid succession followed by continuous infusion. There was a transient 2- 3 min period of tachcardia and hypertension as would be anticipated following epinephrine. Thirty-five minutes after injection of local anesthetic the tourniquet was deflated for seqential periods of 10 sec with 1 min periods of reinflation for 2 cycles followed by deflation for 20 sec and reinflation for 2 min for 2 cycles then final deflation. The patient was awake and talking throughout the entire period of tourniquet deflation which took 6 min. She was questioned continuously as an assessment for changes in mental status. There were none.
There were no hemodynamic changes. BP remained 95-110 systolic with HR 66-70.
Intralipid, 250 ml had been administered prior to tourniquet deflation. The patient's weight was 150 lbs. Another 250 mls of Intralipid was infused upon transfer to PACU. The patient continued to remain awake and alert for two and one half hours in PACU without hemodynamic or ECG changes. The patient was offered an overnight observation bed, but because she was asymptomatic and felt well she elected to go home. Follow up by phone the next morming revealed no subsequent problems. Sensation and movement had returned to the extremity but this occurred several hours after discharge.
I wanted to post this case because it felt like I was being asked to defuse an unexploded bomb. I don't know that the bradycadia exhibited by the patient was a warning or just an aberration. I was still faced with the problem of what to do upon tourniquet deflation. Perhaps I could have kept the tourniquet inflated but for how long? I used the bradycardia as a sign of impending cardiac complications and that keeping the tourniquet inflated may not influence the outcome as the patient was already exhibiting signs of cardiac
toxicity. However, I did want to get Intralipid on board before tourniquet deflation in order to ameliorate any further problems.
I welcome your thoughts on how you would have dealt with this dilemma, i.e.,treat prophylactically as I had done, or deflate the tourniquet and treat any complications that may susequently arise.

Guy, thanks for your reply and confirmation that my chosen course of action was not unreasonable. This case occurred at a small rural hospital that does not do thoracic or vascular, much less cardiac cases. The thought about transferring this patient to a medical center with CPB capbility did occur but the closest facility is about 45 min away.
I hope that no one else will have to experience what I went through, but at least this case can provide some guidance to others. Thanks again,
Karlon Young

Karlon: a few questions (a brilliant save by the way; as I was reading your report I was struck by the impossibly difficult spot you were in, and I too thought of the unexploded bomb) 1) were both tourniquets inflated to 250 mm Hg during injection of local, or only one, and which one? 2) where was the intravenous catheter you used for local injection relative to the tourniquet? In the hand, or closer to the tourniquets? 3) were either of the 2 tourniquets deflated/reinflated (e.g., for tourniquet pain) after the bupivacaine injection, but before your controlled deflations? 4) was this a young, healthy patient or something else?

I'm trying to figure out how bupivacaine could have gained access to the circulation under the tourniquet to produce the initial bradycardia. Thanks. Again, a nice job 'defusing' a potentially lethal situation.

Tim

Tim,
The patient is a 50 yr old female in relative good health except for being a one pack/day smoker.
The i.v. catheter was placed distally in the hand. The proximal cuff was inflated after the distal cuff was inflated and then the distal cuff was deflated. The local was injected at this point (with only the proximal cuff inflated). The distal cuff was not re-inflated, nor was the proximal cuff deflated to deal with tourniquet pain. The patient never complained of tourniquet pain. She was sedated with a continuous propofol infusion throughout the procedure. The propofol was stopped at the onset of the bradycardia.
I do not have the ECG tracings, but I am pretty certain that the QRS was not widening. I don't recall what was going on with the QT interval.
Karlon

Dr. Young:

I am a member of Dr. Weinberg's lab, and am composing an editorial on lipid rescue for submission to an anesthesiology newsletter. I think this case is especially compelling, and would love to include mention of it if you are alright with it. Please let me know here or by email if you would be supportive- not a formal case report, but more anecdotal mention. Thanks a bunch.
Luke Edelman

Karlon,
are you going to write up your case?
Guy

Yikes!!!! At least the mistake was picked up BEFORE the tournequet was deflated. Good, quick thinking.

Very well done. I can report a similar case wherein bupivacaine was erroneously infused in a Biers block with disasterous result (before lipid rescue!).

I wonder what your thoughts are on lipid infusion to the ipsilateral limb prior to cuff deflation, in addition to systemically. Drug sequestration to lipid before potential systemic bolus with re-establishment of limb perfusion may have further de-fused the bomb. Just a thought.

well done
It is always better to prevent a complication than treating it when it occurs. I was wondering if we can give at least some intralipid intravenously before tournquet release. God bless you

Dr Ali Lashari
Dept of Anesthesia
Jinnah Hospital
Lahore, Pakistan