Lanier, William L.

Cerebral Function and Muscle Afferent Activity Following Intravenous Succinylcholine in Dogs Anesthetized with Halothane: The Effects of Pretreatment with a Defasciculating Dose of Pancuronium. By WL Lanier, PA Iaizzo, and JH Milde. Anesthesiology 1989; 71:87–95. Reprinted with permission. By the mid-1980s, it was widely assumed that if the depolarizing muscle relaxant, succinylcholine, given IV, produced increases in intracranial pressure, it did so because fasciculations produced increases in intrathoracic and central venous pressures that were transferred to the brain; however, there was no direct evidence that this was true. In contrast, we explored the possibility that the succinylcholine effect on the brain was explained by the afferentation theory of cerebral arousal, which predicts that agents or maneuvers that stimulate muscle stretch receptors will tend to stimulate the brain. Our research in tracheally intubated, lightly anesthetized dogs discovered that IV succinylcholine (which does not cross the blood-brain barrier) produced a doubling of cerebral blood flow that lasted for 30 min and corresponded to activation of the electroencephalogram and increases in intracranial pressure. Later, in our Classic Paper, we were able to assess simultaneously cerebral physiology and afferent nerve traffic emanating from muscle stretch receptors (primarily muscle spindles). We affirmed that the cerebral arousal response to succinylcholine was indeed driven by muscle afferent traffic and was independent of fasciculations or increases in intrathoracic or central venous pressures. Later research in complementary models demonstrated that endogenous movement (e.g., coughing, hiccups) produced a cerebral response very similar to IV succinylcholine, apparently as a result of the same muscle afferent mechanisms, independent of intrathoracic and central venous pressures. Thus, the importance of afferentation theory as a driver of the cerebral state of arousal and cerebral physiology during anesthesia was affirmed.

Modern medical practice, and particularly that within the hospital environment, has been under intense scrutiny in an attempt to improve patient safety and optimize outcomes. Anesthesiology has been cited as among the most successful specialties effecting improvements. According to the Institute of Medicine's 1999 report, To Err is Human, “… anesthesiology has successfully reduced anesthesia mortality rates from two deaths per 10,000 anesthetics administered, to one death per 200,000 to 300,000 anesthetics administered.” The current report reviews representative highlights from 30 years of progress in improving anesthesiology safety and offers a speculative synthesis of the factors critical to past and future successes. The seven identified points include 1) the emergence of a champion and his allies, 2) initial efforts to identify and quantify broad-reaching problems, 3) research addressing intellectually “amusing” problems of relevance to practitioners, 4) reaching out to others with focused expertise in problem prevention and problem solving, 5) sharing the responsibility for quality and safety improvement with other specialties, 6) expanding buy-in and participation within the anesthesia community, and 7) preparing for the future. The factors provide not only an accounting of anesthesiologists’ successes, but also a road map for other groups and specialties desiring to emulate the anesthesiologists’ experience.

In 2017, JAMA: Journal of the American Medical Association published the results of the MINT trials, prospective research involving 681 patients, all of whom received exercise therapy for low back pain. Half of the patients were randomized to additionally receive radiofrequency denervation (RFD) treatment. 88% of patients completed the 3-month follow-up, and 77% completed the 12-month follow-up. In this context, RFD provided no added benefit over the baseline of exercise therapy. In 2018, five authors, all experts in pain medicine, published a ‘Daring Discourse’ article in the journal Regional Anesthesia and Pain Medicine (RAPM), criticizing the findings of the MINT trials. Although 3 of the 5 authors of the RAPM ‘Daring Discourse’ article reported in conflict of interest statements—as is appropriate—that they were consultants to corporations that produce RFD equipment, the authors failed to disclose that 4 of 5 are on the editorial board of RAPM and all 5 are current officers in the medical organization that owns RAPM: that is, the American Society of Regional Anesthesia and Pain Medicine. Noteworthy, there was no published response from the MINT trial investigators to the Daring Discourse criticisms, either in the aforementioned example or in downstream venues where some of the same Daring Discourse authors continued their widely disseminated criticisms of the JAMA/MINT trials report. We believe that these actions taken by the Daring Discourse authors and RAPM have unfairly tipped the scales in the evaluation and application of RFD treatment of low back pain. In our commentary, we discuss: (1) the challenges associated with using clinical trials to predict clinical efficacy, (2) appropriate and inappropriate uses of postpublication commentary on original research findings, (3) the use of inappropriate commentary (and related means) to alter clinical practice in the presence of contradictory research findings, and (4) potential conflicts of interest related to the authors’ and Journal’s publication of the unopposed MINT trials criticism.

Purpose To study the effect of a planned social media promotion strategy on access of online articles in an established academic medical journal. Method This was a single-masked, randomized controlled trial using articles published in Mayo Clinic Proceedings , a large-circulation general/internal medicine journal. Articles published during the months of October, November, and December 2015 (n = 68) were randomized to social media promotion (SoMe) using Twitter, Facebook, and LinkedIn or to no social media promotion (NoSoMe), for 30 days (beginning with the date of online article publication). Journal website visits and full-text article downloads were compared for 0–30 and 31–60 days following online publication between SoMe versus NoSoMe using a Wilcoxon rank-sum test. Results Website access of articles from 0 to 30 days was significantly higher in the SoMe group (n = 34) compared with the NoSoMe group (n = 34): 1,070 median downloads versus 265, P < .001. Similarly, full-text article downloads from 0–30 days were significantly higher in the SoMe group: 1,042 median downloads versus 142, P < .001. Compared with the NoSoMe articles, articles randomized to SoMe received a greater number of website visits via Twitter (90 vs 1), Facebook (526 vs 2.5), and LinkedIn (31.5 vs 0)—all P < .001. Conclusions Articles randomized to SoMe were more widely accessed compared with those without social media promotion. These findings show a possible role, benefit, and need for further study of a carefully planned social media promotion strategy in an academic medical journal.

AbstractWe describe two patients—both who underwent general anesthesia—in whom we theorize that hydraulic pressure on carotid artery baroreceptors resulted in transient asystolic cardiac arrest (TACA) during diagnostic or therapeutic procedures. Patient #1 was a 58‐year‐old female who experienced TACA in response to rapid injection of radiocontrast material into the carotid artery during diagnostic cerebral angiography. Her history was remarkable for aneurysmal subarachnoid hemorrhage at least 13 hr prior to angiography, radiographic evidence of intracranial hypertension, and baseline bradycardia, collectively suggestive of increases in baseline vagal tone. Potentially contributing to TACA, the patient had a 90° curve in the internal carotid artery, just distal to the carotid bifurcation and tip of the angiography catheter, that likely diminished runoff of injected contrast solution and, in turn, would have exacerbated any intracarotid pressure increases in response to injection. There was no evidence of increased baseline vagal tone in Patient #2, a 79‐year‐old female having carotid endarterectomy surgery. She experienced TACA immediately after full release of an occlusive clamp on the common carotid artery proximal to the now closed carotid arteriotomy, but while the internal carotid was still occluded. Of note, the carotid artery baroreceptors were not treated with local anesthetic in these patients, thus they should have retained much of their normal function. We describe the possible pathomechanisms involved in TACA in these patients, measures to diminish the likelihood of the phenomenon occurring in future patients, and methods for treating the asystole.

Background: Thyroid-stimulating hormone (TSH)–secreting pituitary adenomas are a rare cause of secondary hyperthyroidism. Anesthetic management of these patients has not been formally described in the literature. Materials and Methods: Patients who underwent resection of a TSH-secreting pituitary adenoma during 1987 to 2012 at a single institution were identified. Preoperative thyroid hormone state, anesthetic management, and outcome were recorded. Hemodynamic associations with intraoperative events were compared between those who were hyperthyroid and euthyroid at the time of surgery. Results: Of 2268 patients having transsphenoidal resection of a pituitary tumor, 19 (0.84%) had resection of a TSH-secreting adenoma. At the time of surgery, 6 (32%) were hyperthyroid, 11 (58%) were euthyroid, and 2 (10%) were hypothyroid based on serum thyroxine concentration. General anesthesia was maintained with a potent inhaled anesthetic in all patients, and included nitrous oxide in 18 of 19 (95%). Seventeen (90%) had an arterial catheter placed for surgery. Only 1 patient (5%) required an intraoperative blood transfusion. There were no significant differences in heart rate or blood pressure at induction of anesthesia, upon intranasal injection of local anesthetic containing epinephrine, or upon emergence from anesthesia, between patients who were chemically hyperthyroid or euthyroid. Twelve of 19 (63%) had tumor extension beyond the sella turcica. Common complications were nausea and vomiting (42%), diabetes insipidus (32%), and temporary or permanent hypopituitarism (42%). Conclusions: Patients having resection of TSH-secreting pituitary adenomas can present in any thyroid state. An awareness of risks and potential complications in patients with TSH-secreting adenomas can help tailor perioperative care.