Anesthesiology, Perioperative and Pain Medicine

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Q&A with Stanford Anesthesia's Residency Director

Clinical questions

Combined residency training in anesthesia and critical care

Question: I am interested in a career in ICU and anesthesia. I know there are a couple of residencies that have a combined anesthesia/critical care medicine track. Does Stanford offer one?

Answer: Great question. Thank you. Critical care medicine has a long (36 years) and strong (157 fellows trained) tradition at Stanford. And, I have been impressed by how many medical students consider anesthesiology for a career because of their interest in critical care.

Stanford Anesthesia has applied this year for approval from ACGME for a combined anesthesia/critical care medicine training track within the residency. We expect to hear back from the ACGME in November 2011. Should the combined program be approved it will be an option for applicants graduating medical school in 2012. We have requested to make available two slots for CA1 through CA4 training (i.e. it does not include the PGY1 year) so that after 5 years the trainee would be eligible for board certification in both specialties.

The intent of a combined track in anesthesiology and critical care is to facilitate the training of the dual anesthesiologist-intensivist. During the CA1 and CA2 years, there would be increased critical care exposure (2 months/year instead of 1), so that by the CA3 year, additional ICU months are performed in a fellow's role with more supervision of junior residents.

The proposed Stanford combined tract would also involve moving some of the CA3 rotations to the CA4 year. This allows residents in the combined track to do OR anesthesia rotations during their last year of training.

The proposed program also offers space in the CA3 year for electives (up to six months). These elective months can be spent doing either critical care relevant rotations (such as infectious disease, transthoracic and transesophageal echo, nephrology, pulmonary medicine) or as research months so that the trainee can design and finish research that facilitates their move toward grant awards and a successful launch to an academic career.

The way it was proposed to ACGME the combined training track would be a separate entity from the standard anesthesia residency with its own match.

This program is expected to attract someone who knows early in medical school that they want to be an anesthesiologist-intensivist. We believe trainees will benefit from the overlapping of the residency and fellowship training that is not allowed by the traditional sequential training (3 yr Anesthesia Residency followed by 1 yr critical care fellowship). Patients in the OR and in the ICU will benefit from physicians cross-trained in both areas.

As soon as there is more to update you with I will,
Thank you,
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Nice article about anesthesia

I hope you enjoy reading this article as much as I did!
Eger EI 2nd. After you, please: the second Annual John W. Severinghaus Lecture on Translational Science. Anesthesiology. 2010;112(4):786-93.
He describes the challenges of his very first day delivering anesthesia, the origins of the concentration effect, the increase in CO2 in an apneic patient, how MAC came to be, expansion of the bowel from nitrous, why IQ goes up after general anesthesia (learning effect), and how the rate of increase of alvelaor gas concentration is faster in rats than in whales because ventilation and perfusion per kg is greater in the smaller animal.


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Wake-up with inhaled anesthetics

Question
I have been looking for papers regarding turning off isoflurane and starting Desflurane at the end of a case regarding accelerating the wakeups. To me it makes sense, but someone told me this did not matter clinically. Do you know of such a paper describing this? Thank You,

Answer
Research articles on low solubility inhaled anesthetics are often written by investigators funded by Baxter (Desflurane) or Abbott (Sevoflurane) so as usual when reading the literature see who funded the study and how that might affect the findigs. The classic paper on the switching (or crossover) technique you describe is attached.
Download file
The lessons learned are that if one is to substitute desflurane for isoflurane at the end of a case one needs to keep in mind that partial rebreathing through a semiclosed circuit limits elimination of isoflurane more than you may think during the crossover or switching period. A higher fresh gas flow than expected during this crossover period is needed to speed the isoflurane elimination. Alternatively, start the crossover earlier than you might think you need if flows are low to ensure that isoflurane is gone by the end of the case.

Having used isoflurane exclusively for the first part of my career (I like sounding like a veteran of the field) I know I woke patients up just as fast as I do now. This was done by starting to reduce the inspired isoflurane concentration as the end of a case approached. Desflurane and sevovoflurane do provide the practitioner more margin for error, as turning the desflurane or sevoflurane vaporizer off at the very last minute of closure often yields a reasonably fast wakeup. Please keep in mind that studies that show a faster wakeup with desflurane or sevoflurane versus isoflurane use a protocol where the gas is left at the 1 MAC level, for example, until skin closure is finished, and only then is the vaporizer turned off. It is no surprise then that wakeup is faster the lower the blood gas solubility is. This protocol maynot reflect the actual practice by many anesthetists of titrating the inhaled anesthetic concentration down as case is coming to an end.
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Blood pressure in sitting position

Question from resident
Hello, A quick question. I usually level the transducer for an arterial line to the heart. Usually this is also about the position of the brain based on the supine or prone position. Yesterday I did a long case where towards the end they wanted the patient sat up. Previously MAPs had been mid 70's, UOP 1-1.5 cc/kg/hr. I moved the transducer up to heart level with pt sitting up, and MAPs were low 70's. 5 minutes later my attending came in the room and moved the transducer at the level of the head, at which time the patient's MAP was measured as 58-60 which lead to a different perception of what adequate pressure in a patient is. Clearly, a good pressure does not automaticaly mean good flow. I also know the conversion is about 1 mmhg for every 1.4 cm H20. I have had a similar discussion for beach chair position for ortho, but have never done a sitting neurosurg case. I will read about this, but could you give me a broader perspective on your practice.

Answer
Nobody really knows the definitive answer to your good question about where to place the transducer when the patient is not flat, but the issue revolves around whether the circulation above the heart functions as a siphon system or as a waterfall system. The two best sources, besides Dr. Jaffe our esteemed neurosurgical anesthesia faculty, that provide a balanced analysis are:
http://www.apsf.org/assets/Documents//spring2009.pdf
and
http://www.apsf.org/resource_center/newsletter/2008/winter/17_problems_of_posture.htm
Until actual data of some sort sort all this out, my own practice is to measure BP at the level of the most vulnerable tissue--the brain and then aim to maintain MAP within the patients unanesthetized preop BP.
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