Antithrombin III

The other day we had a patient come in for a CABG. Aside for some coronary artery disease, hypertension, and chronic kidney disease, the patient was pretty healthy. They were not on anticoagulation prior to the procedure.

After I gave full dose heparin for going on bypass (41,000U in this case), the ACT only came up to 422. An additional 10,000U of heparin was given with a repeat ACT of 457. Still, our surgeon was not quite comfortable with that number and requested an additional 10,000U heparin. The ACT came to 477.

If the ACT stayed in the low 400s, would you go on bypass? What if the ACT had not responded to the repeated heparin dosings?

Management of coagulation during cardiopulmonary bypass. Continuing Education in Anaesthesia Critical Care & Pain, Volume 7, Issue 6, 1 December 2007, Pages 195–198, https://doi.org/10.1093/bjaceaccp/mkm036.

Antithrombin III concentrate to treat heparin resistance in patients undergoing cardiac surgery. J Thorac Cardiovasc Surg. 2002 Feb;123(2):213-7.

Would you give antithrombin III or plasma?

Treating Heparin Resistance With Antithrombin or Fresh Frozen Plasma. The Annals of Thoracic Surgery. June 2008Volume 85, Issue 6, Pages 2153–2160.

Is there evidence that fresh frozen plasma is superior to antithrombin administration to treat heparin resistance in cardiac surgery? Interact Cardiovasc Thorac Surg. 2014 Jan; 18(1): 117–120.

We ultimately decided to go on bypass. Repeat ACTs on bypass were in the 500s. No antithrombin was given. After separation from cardiopulmonary bypass and administration of protamine, repeat ACT was 111. Protamine was dosed accordingly to heparin administration and ACTs while on bypass.

Recommendations for the use of antithrombin concentrates and prothrombin complex concentrates. Blood Transfus. 2009 Oct; 7(4): 325–334.

Thrombate (antithrombin III) package insert

HeartWare vs. HeartMate LVAD

A couple of weeks ago, I took care of a patient who desperately needed to get better from acute CHF.  At that time, we placed the patient on an impella… but the next day, it was deemed that he needed ECMO to reperfuse his organs.  After a week on ECMO with continued impella support, ECMO was titrated down and off while maintaining 3.9L/min flow from the impella.  During the wean off ECMO, the patient had been extubated and was mentating clearly and interacting appropriately.

Fast forward a couple days after getting extubated, the patient was ripe for an LVAD.  But which one? (We ended up placing the patient on HeartWare LVAD).

YouTube: LVAD 101 – Anatomy & Physiology

YouTube: LVAD Pathophysiology


HeartWare

heartware-hvad-7x4

HeartWare brochure

YouTube vid of HeartWare (no sound) ; Vid of HeartWare with detailed explanation

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HeartMate II

heartmate-index_1

HeartMate II website

YouTube vid of HeartMate II


Summary

  • Cost-effectiveness: HeartWare > HeartMate II (UK NHS study, April 2014)
  • LV Geometry: HeartWare = HeartMate II (J CT Surg, 2013)
  • Stroke & GI bleed risk: HeartWare > HeartMate II (J Card Surg 2013)
  • Risk of device failure: HeartWare < HeartMate II
  • ENDURANCE trial: Randomized patients eligible for DT 2:1 to the HeartWare centrifugal flow LVAD versus the HeartMate II axial flow LVAD. The trial did reach its primary noninferiority endpoint of stroke free survival at 2 years (55.0% in the HeartWare patients versus 57.4% in the HeartMate II patients). Of note, a change in the design of the HeartWare device during the trial (sintering of the inflow cannula) appeared to decrease the incidence of pump thrombosis. Overall, the stroke rate was higher in the HeartWare arm whereas device malfunctions requiring exchange or urgent transplantation were more common in the HeartMate II arm. Data analysis suggested that better blood pressure control in the HeartWare arm may decrease the stroke rate and a second cohort of patients is being enrolled with more attention being paid to blood pressures management.

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Ventricular Assist Devices: Impella

“There’s an emergent case coming for impella placement.”

Impella?  I’ve read about these devices and I’m familiar with managing patients on LVADs as well as providing anesthesia for LVAD placement.  But, I’ve never done an Impella on a critically unstable patient.

YouTube video describing the purpose and placement of the Impella

Cath Lab Digest: Overview of Impella 5.0

home-graphic-role

Anesthesia & Analgesia; January 2012. Echo rounds: The Use of TEE for Confirmation of Appropriate Impella 5.0 Device Placement.

From A&A Echo Rounds

 YouTube video similar to our axillary artery conduit (we had to go left sided bc of a prior AICD in the patient’s right chest) for Impella 5.0

JCVA, June 2010. Review Articles: Percutaneous LVAD: Clinical Uses, Future Applications, and Anesthetic Considerations.

Awake Tracheostomy

They say that anesthesiology is 95% comfy and relaxed and the other 5% is “oh shit”!  It’s a great career choice — pretty flexible hours, great patient contact, broad spectrum medicine, crisis management, leadership role, etc.

There happened to be an interesting case in the OR — awake tracheostomy for a patient coming in from home.

What’s a tracheotomy?

Evaluation of the airway PPT

The Difficult Airway in Head and Neck Tumor Surgery

Anesthesia for tracheostomy for huge maxillofacial tumor. From SJA: CASE REPORT Year : 2014 | Volume : 8 | Issue : 1 | Page : 124-127

Our patient had two prior tracheotomies all with successful decannulation.  His most recent trach was about 2.5 months ago (which a fiberoptic intubation was used with a 6.0 ETT).   He had a neck cancer with a rapidly growing tongue base tumor that seems to be less responsive to chemo than his shrinking neck tumor.  Because of the enlarging size of the tongue base tumor, he is starting to notice worsening stridor without his trach.  The ENT surgeon evaluated his airway just days before and deemed it unintubateable.  Therefore, my plan was to have a pedi FO scope with 5.0 cuffed ETT (smallest available in our OR), glidescope, emergency cric supplies (14g angio cath, 3cc syringe with plunger removed and 7.0 ETT adapter hooked into the end of the syringe), jet ventilator and tubes, and ENT surgeon.

We decided to use a bit of midazolam as well as Precedex for the awake trach.  The dosing on the package says 1 mcg/kg for 10 minutes then 0.7 mcg/kg/hr.  We started with 0.5 mcg/kg for 10 minutes then 0.5 mcg/kg/hr.  This regimen worked well as we started it in preop and monitored his SpO2 as he dozed off but was easily aroused to voice and gentle touch.

The Role of Dexmedetomidine for Awake Trach

Monitors were placed in the OR and we used a face mask running 10 L/min O2 with ETCO2 monitoring.  Every now and then he would obstruct while lying supine, therefore, we placed a nasal trumpet to aid the obstruction.  The surgeon localized the surgical area. See video for procedure.

The patient coughed once the trachea was perforated, but it was short lived as the surgeons were able to place the trach and hookup to our anesthesia circuit.  After confirming ETCO2, we pushed propofol IV and the remainder of the case was performed under general anesthesia (direct laryngoscopy and biopsy by surgeon).

Key take home points

  • Effective communication with the patient pre-op: expectations, sedation, potential complications.
  • Arm yourself! Do this like you would a difficult airway! Fiberoptic intubation supplies, glidescope, emergency cricothyroidotomy supplies, backup LMA, extra hands on deck (grab your anesthesia colleagues, anesthesia techs, extra help!), ENT… it never hurts to be over prepared!
  • Deliberate, effective communication with the ENT colleague across the drape.
  • Document any intubation performed, tools used, trachs placed so your anesthesia colleagues will know what worked in the past to secure an airway.
  • Breathe a sigh of relief bc these kind of cases are extremely uncommon!  Pat yourself on the back for a job well-done!

Now check out this amazing Case Report on a patient with a massive maxillofacial tumor!

When the bark is louder than the bite

In residency, you learn to deal with many different personalities.  This ranges from super sweet and helpful to utterly cruel and egotistical.  At MGH, our CA-3 year was spent running the call schedule on night call (the first-call experience).  It’s a terrific experience in prioritizing as well as organizing your team to prepare for what rolls through the OR doors.  Fast forward 4 years and now I’m in private practice.

While running the schedule on call, I get a call from the trauma surgeon saying a patient with an epidural hematoma needs to come to the OR emergently and couldn’t wait for another anesthesiologist to be called in from home (home call gives an anesthesiologist 30 minutes to come into the hospital for an emergency).  So, I made the executive decision to pull the anesthesiologist from the elective suboccipital craniotomy case to do the emergency.  It was a crani to crani and neuro to neuro switch… meaning the neuro team and crani trays were already open and ready to go.  It made the most sense in my mind.  Of course, without missing a beat, the “elective” neurosurgeon showed complete disdain of my decision.  To add fuel to the fire, he proceeded to berate the OR nurses, myself, and staff to make sure his displeasure was known.  I stood by my decision because it was the best decision for the emergency craniotomy patient who could have potentially died.  Secondly, I chose not to call in my final anesthesiologist for an elective case as we would have gone on “trauma bypass”.  This means that no traumas or emergencies could come to our hospital.  The “elective” neurosurgeon became more livid by the minute.  2.5 hours after he was supposed to start his case, I finished my first case and was able to get his case started.

Now, who does an elective suboccipital craniotomy for tumor case on a Saturday?  Secondly, he decides to do this in a sitting position — this has it’s own sets of risks.  He needed a precordial doppler, which our hospital did not have, so we called for it from our neighboring sister hospital.  In the meantime, I had another plan…that was to put down a TEE probe to monitor for venous air embolism (VAE).  After speaking to the patient and family, I proceeded to explain the risks/benefits of arterial line, central venous line, transesophageal echo, mechanical ventilation, blood transfusion, and intensive care unit stay.  It’s always a lot for the family to comprehend, especially while meeting them for the first time.  However, it is our job as anesthesiologists to make them comfortable and calm their fears.

**This picture taken from a google search for “precordial doppler”.  It is not my own.**

IndianJAnaesth_2012_56_5_502_103979_u2

**This picture taken from a google search for “precordial doppler”.  It is not my own.**

We get to the room and proceed with vital signs monitoring.  Uneventful induction and intubation.  A right internal jugular vein central venous line is placed (mainly to use as a Bunegin-Albin catheter).   TEE probe placed to look for air in RV and possibly air lock and RV failure –> VAE.  Radial arterial line placed and transduced at the level of the head.  Pt was placed in Mayfield pins and positioned in steep sitting position with reverse Trendelenberg and flexing the legs up.  Neuromonitoring commenced looking for changes in sensory and motor signaling.

All throughout the case, the TEE showed various amounts of air coming through the right side of the heart:

IMG_6787.PNGWith greater amounts of air, there would be a detectable decrease in blood pressure as well as end-tidal CO2.  While the right ventricle was still capable of pushing blood forward, I simply increased the blood pressure pharmacologically and increased the patient’s volume with normal saline from the IV.  Rarely does one get to see this TEE view as most of these cases are monitored non-invasively via pre-cordial doppler or ETCO2 and BP.

Lastly, this patient had a great outcome.  A 2cm x 2 cm hemangioma was resected with minimal disruption or trauma to surrounding tissue.  2 hours after a lengthy 4 hour surgery, the patient was sitting with their family… communicating and interacting with them.  All motor and sensory intact.

Pearls from this case:

1) Always do what is best for the patient.  When a life-and-death situation presents itself, it gets priority.  Period.  It doesn’t matter what pressure or temper tantrums you get from outside parties.  Make the best clinical decision. Organize a plan.  Stick with it.

2) Find out the surgeon’s plan.  This case was not booked in sitting position.  Some of these cases are done in prone position, which makes the likelihood of VAE significantly lower than in sitting position.  Knowing the surgeon’s plan of attack is critical to an anesthetic plan.

3) Read. Read. And read more.  Although I’ve been out of residency and fellowship for 4 years, cases will always test your knowledge as well as make you learn new skills/techniques to better your plan.  Take the time to do your best.  Always review.  Medicine is a lifelong learning career.

4) Don’t sweat the small stuff.  The “elective” neurosurgeon who raised such hell at the beginning of the case was thanking me for my help and expertise by the end of the case.  Learn as much as you can from your residency.  Take the knowledge gained and let your clinical acumen do the talking.  There is no room for ego when taking care of a patient.  Your ability to be well-read, well-trained, and well-respected will dictate the tone.  No fluff is needed when you bring 100% to the table.  Don’t be intimidated by the loud bark.

Call for help

April 11, 2010 (CA-3)

My 1st true difficult airway…. something I hope to never see again, but who am I kidding? It’s my job to be an airway expert… therefore, that only means I will be challenging my skills and will someday encounter that dreaded unintubateable airway.

The patient was a friendly, easy-going gal who was an anesthesiologist’s nightmare. She was coming in for a 3 vessel CABG… she was a known difficult IV access (yes, she came from the floor with an infiltrated 22g IV). She stood proud at 5’3″, 255lb, short chin, small mouth opening, and thick neck. She had had her cath done a couple days prior to her surgery — and yes, the radial artery was used. In addition to her already challenging anatomy, the surgeon requested that her other radial artery be spared for grafting.

I go to meet her in the holding area. She was so nice…friendly… had a positive attitude. These are the patients I love to care for. After updating her H&P and checking her consent, I apprehensively started searching for venous access. 3 PIV sticks..with flash but no luck. 2 attempts with U/S…no luck. Luckily, my a-line went in without any trouble. The attending tried several times for a PIV as well with U/S.. no luck.

We wheeled her back to the OR. She had a rather unchallenging R IJ MAC introducer placement (thank goodness!). Now to go to sleep!

We had a glidescope and bougie handy… knowing this intubation could be difficult. (In retrospect, I would’ve had the fiberoptic cart and an LMA within reach). We pre-oxygenated in reverse T-burg for what seemed like forever. Go time: Prop, sux,… glidescope…. barely saw arytenoids…even with a glidescope!! Small mouth opening kept us from truly getting the styletted tube in her mouth. I took a look for what felt like maybe 5 seconds and could eerily hear the sat probe dwindle down… 100….98……95……92….87….84…. time to mask ventilate!! We 2-hand mask her… a very difficult mask! Oral airway in…still difficult. Reposition, jaw lift,…sats 64…52….39… “Call for help” exclaimed my attending! I called out for an LMA and a bougie and told the surgeons to be on standby for an emergency airway.

Fortunately, we were able to place an LMA #4 and slowly ventilate her back up to 100% sat. By now, there were 3 other anesthesiologists and an anesthesia tech who came to help.

We had an airway, but couldn’t proceed with the surgery with just an LMA…we needed to secure her airway. We switched over to a Fast trach LMA#5…one that would accomodate a 7.0 ETT. We used a fiberoptic scope to look down the LMA. It was difficult to discern the structures. She had a pretty small glottic opening…and after several attempts, we were able to guide the fiberoptic scope down into the trachea and secure a breathing tube for ventilation.

Once the tube was secured… I took a step back and realized this could have been a disaster. However, we initiated all the right things in the difficult airway algorithm and saved this woman’s life. It was incredible.

After her surgery, we delivered her to the SICU, intubated. She was extubated the next morning under the supervision of an anesthesiologist. Everything went well. She recovered well from her CABG and was informed to have “difficult airway” written all over her medical record.

Key points:
-Call for help early
-Always have backup airway devices ready
-Even as a resident, don’t depend on your attendings to bail you out of trouble….b/c someday, that “attending” will be you.
-Reflect at the end of a challenging case

Calm before the storm

March 5, 2010

People who have witnessed and/or survived crazy forces of Mother Nature often state that there’s a “calm before the storm”. I have experienced this with tornados growing up in west Texas.

But on OB?
Yep.

The OB anesthesia team was enjoying the fruits of the night team’s labor. All epidurals were in…. most of the ladies had delivered. Life was good! I even had time to prop my feet up and get some reading done. Not only that, we all enjoyed a rather relaxed lunch. It was WAY TOO CALM!!!

Anesthesia STAT was called overhead/paged to our beepers/called to the anesthesia room….

What appeared to be a normal vaginal delivery… turned into any OB’s worst nightmare. The cause wasn’t clearly revealed. We started multiple large bore IVs and sent off blood and raced to the OR. EBL 3L. Once in the OR, complete assessment of the bleeding by the OBs rendered a necessary hysterectomy. The patient was pale white.  Never before had I seen a human so pale, but alive and interacting with us. She didn’t flinch for a 14g PIV or the a-line. I wonder what she was thinking as she could probably feel her life fading away. Belmont, cardiac nurses, cell saver..dozens of people in an OB OR; all wanting to give this woman a chance to see her 5 kids.

PreOX, Cricoid, RSI–>GA. Quick prep. Intraop, a uterine rupture was noted. Hysterectomy completed. Still more bleeding!! Multiple uterine veins were found…just avulsed along the lateral walls of the abdomen. 2 more ob/gyn surgeons called stat for repair. Still no control of the bleeding. Partial aortic compression to help with hypotension. 2 vascular surgeons called. + Confirmation of control of bleeding. Belmont was running about 200ml/min x 120 min. Multiple blood product given (20-30U PRBC, 20-30U FFP, 24 plt, 10 cryo). pH 7.11–>7.38. UOP about 100ml/hr. At it’s lowest, Hb was 4.8 (the lowest I’ve ever seen!). Upon delivery to the unit, pH 7.38, Hb 10, Plt 127 (got as low as 84), PT/PTT slightly elevated, INR 1.2 (1.8 at its highest), fibrinogen 213 (65 at its lowest). She was mechanically ventilated based on the ARDSnet protocol (small tidal volumes, higher PEEP, fast frequency).

This is not something you see everyday…. much less something you see commonly on OB. The wonderful communication between the nurses, surgeons, staff, anesthesia…everyone truly made this a world-class effort. And because of this… a mother cheated death.

Lessons learned:
– Call for help early and clearly
– Practice effective communication
– Close the loop — verify if questions
– Don’t be afraid to get help — there’s many consultants at a hospital
– Debrief — because you’ll never know when you’ll need to be prepared for another “storm”

Walk the line

March 2, 2010

OB Anesthesia can offer a wide entertainment of cases and patients. For example, there is the “uncomplicated” mom who delivers smoothly without complication. There’s the “drug” mom who requests everything under the sun to be comfortable…. or the literal “druggy” mom who is able to tell you where they have the best IV access. Let’s not forget the “perfectionist” mom who has everything planned out from conception to birth. There’s the “multips” who have been through the pregnancy process and are seasoned…. who for the most part are very cooperative and know what to do. The “teeny bopper” moms who often wince at just getting an IV — someone should tell these guys that pregnancy and birth isn’t just about the intercourse and then the baby. There’s the “IVF-ers” who tend to be very nervous about everything along the way, but they’re often the most appreciative of everything you do for them. And finally (maybe I covered them all, but I’m sure I haven’t), there’s the “I just want to be knocked out” mom who basically wants an elective c-section and general anesthesia so they don’t know or feel anything.

Of course, these are just my opinions of the populations I have come across; not true facts. And yes, I realize pregnancy can be a very nerve-racking process. These are just MY descriptors….

Came across an interesting OB anesthesia case. A pt who had an accreta. This was most likely due to her previous 4 c-sections… and she desired a hysterectomy.

Our plan: Multiple large bore PIVs. Arterial line. Type & crossed blood pre-op. Pre-op labs. Blood and fluid warmers. Belmont. Backup RIC and MAC lines available in the room. Peripheral phenylephrine with backup norepi if needed. Epidural anesthesia with backup emergent GA. Constant communication with the surgeons. SICU bed available if needed.

Outcome: Baby delivered and did beautifully. Roughly 1.5L EBL, 2.5L LR. Post hysterectomy ABG with stable Hb. A-line d/c’d. Pt back to OB Labor floor for a couple of hours of monitoring. No SICU bed needed.

Sometimes a full day’s plan helps ward off the evil. It’s nice when you get to deviate away from the “normal” OB anesthetic…and everything goes well. Even if it does seem like over kill.