1001 Effect of Exogenous Albumin on the Incidence of Postoperative Acute Kidney Injury in Patients Undergoing Off-pump Coronary Artery Bypass Surgery with a Preoperative Albumin Level of Less Than 4.0 g/dl
A preoperative serum albumin concentration of less than 4.0 g/dl is independently associated with postoperative acute kidney injury (AKI) in patients undergoing off-pump coronary artery bypass surgery. A randomized, controlled, double-blind trial was conducted to determine whether preemptive albumin administration to correct hypoalbuminemia reduces the incidence of AKI after off-pump coronary artery bypass surgery in 203 patients with preoperative serum albumin concentrations of less than 4.0 g/dl. At induction of anesthesia, patients randomly assigned to the albumin group were administered a volume of 20% human albumin determined by their preoperative serum albumin concentration while patients randomized to the control group were administered the same volume of 0.9% sodium chloride. Preemptive albumin treatment reduced the risk of AKI by 47%, although there were no differences in either the need for renal replacement therapy or mortality. See the accompanying Editorial View on page 983.
1032 Severe Nausea and Vomiting in the Evaluation of Nitrous Oxide in the Gas Mixture for Anesthesia II Trial
The Evaluation of Nitrous oxide In the Gas Mixture for Anesthesia (ENIGMA) II trial randomly assigned 7,112 at-risk noncardiac surgery patients to a nitrous oxide anesthetic or a nitrous oxide–free anesthetic. The incidence of severe (persistent or recurrent) postoperative nausea and vomiting (PONV) was recorded prospectively as a prespecified secondary endpoint. Nitrous oxide increased the risk of severe PONV from 11% in patients receiving a nitrous oxide–free anesthetic to 15% in those receiving an anesthetic including nitrous oxide, and the increased risk was essentially eliminated by antiemetic drug prophylaxis. Nitrous oxide–induced severe PONV was more likely to occur in Asian patients. Severe PONV was more likely in those undergoing gastrointestinal surgery and was associated with postoperative fever, poor quality of recovery, and prolonged hospitalization.
1053 Adductor Canal Block Provides Noninferior Analgesia and Superior Quadriceps Strength Compared with Femoral Nerve Block in Anterior Cruciate Ligament Reconstruction
Femoral nerve block is an effective analgesic technique for ambulatory anterior cruciate ligament reconstruction but it weakens the quadriceps muscle. This randomized controlled trial tested the joint hypothesis that adductor canal block provides noninferior analgesia, as measured by the cumulative opioid consumption and pain scores during the first 24 h postoperatively, and preserves quadriceps femoris muscle motor strength compared with femoral nerve block in 100 adult patients undergoing ambulatory anterior cruciate ligament reconstruction. Adductor canal block was a superior analgesic modality to femoral nerve block in patients undergoing anterior cruciate ligament reconstruction because it provided postoperative analgesia that was as effective as that of femoral nerve block while producing less weakness of the quadriceps femoris muscle measured by postblock maximal voluntary isometric contraction during knee extension of the operative limb.
1168 Evaluation of the Foundation for Anesthesia Education and Research Medical Student Anesthesia Research Fellowship Program Participants’ Scholarly Activity and Career Choices
Exposure to research in medical school increases medical student interest in both research and academic careers. The Foundation for Anesthesia Education and Research created the Medical Student Anesthesia Research Fellowship (MSARF) program in 2005 to increase the pool of physician investigators in anesthesiology. In this 8-week program, medical students are matched with research mentors in academic anesthesiology departments and assigned a project. The research productivity of students participating in the MSARF program from 2005 to 2012 was determined as was the percentage of students who entered an anesthesiology residency program. Forty-two percent of 346 MSARF projects were published and 30% (105) of MSARF students were authors on peer-reviewed publications. Fifty-eight percent of 255 students for whom residency match data were available matched into anesthesiology residency programs. See the accompanying Editorial View on page 996.
1012 Auscultation versus Point-of-care Ultrasound to Determine Endotracheal versus Bronchial Intubation: A Diagnostic Accuracy Study
Bronchial intubation is the most common endotracheal tube (ETT) malposition. The use of auscultation, the standard method for determining ETT location, to distinguish between tracheal and bronchial intubation has a reported sensitivity of 60 to 65%. A double-blinded randomized study was conducted to assess the accuracy of a point-of-care ultrasound examination in determining the position of the ETT. Forty-two patients requiring general anesthesia were randomly assigned to right main stem bronchus, left main stem bronchus, or tracheal intubation, and anesthesiologists blinded to the position of the ETT attempted to identify its location based on auscultation of breath sounds and by means of the ultrasound exam. Auscultation had a sensitivity of 66% and a specificity of 59%, while ultrasound had a sensitivity of 93% and a specificity of 96%. See the accompanying Editorial View on page 989.
1041 Tapered-cuff Endotracheal Tube Does Not Prevent Early Postoperative Pneumonia Compared with Spherical-cuff Endotracheal Tube after Major Vascular Surgery: A Randomized Controlled Trial
The first postoperative pneumonia episode after major surgery could be related to intraoperative risk factors for microaspiration and may be prevented by improving perioperative tracheal sealing. The continuum of minimum-to-maximum diameter sections of tapered-shape endotracheal tube cuff might better fit the tracheal walls than a standard cuff with fixed diameter. A study to assess the effect of tapered-cuff endotracheal tubes on the postoperative pneumonia rate and microaspiration frequency was conducted in 109 patients randomly assigned to receive either spherical (standard-cuff) or taper-shaped (tapered-cuff) endotracheal tubes inserted after anesthesia induction and admitted to the intensive care unit after major vascular surgery. First postoperative pneumonia frequencies did not differ between standard-cuff and tapered-cuff groups (44% vs. 42%, respectively). No significant between-group differences were found for microaspiration rates.
1065 Cardiac Slo2.1 Is Required for Volatile Anesthetic Stimulation of K+ Transport and Anesthetic Preconditioning
Clinically relevant doses of halogenated volatile anesthetics can protect the heart from ischemia and reperfusion injury. The mechanism of anesthetic preconditioning involves signaling pathways thought to converge at the level of mitochondria through distinct K+ channels. Several K+ channel types exist in mitochondria, including large conductance channels of the Slo gene family. The mammalian Slo channel family includes Slo2.1 (KCNT2, Slick) and Slo2.2 (KCNT1, Slack). The hypothesis that one of the mammalian SLO-2 orthologs, Slo2.1 or Slo2.2, may underlie anesthetic preconditioning in mammals was tested using novel gene deleted mice (Slo2.1-/-, Slo2.2-/-, and Slo2.x double knockout). The KNa channel Slick, encoded by the Slo2.1 gene, was required for cardioprotection by anesthetic preconditioning in mice. Slick is responsible for volatile anesthetic-stimulated K+ flux at both the cardiomyocyte plasma and mitochondrial membranes. See the accompanying Editorial View on page 986.
1174 Neural Control of Inflammation: Implications for Perioperative and Critical Care (Review Article)
The inflammatory response is crucial for proper antimicrobial defense and healing after an aseptic injury, but an excessive inflammatory response or failure to resolve the proinflammatory phase may lead to exaggerated tissue injury, circulatory shock, and death. The inflammatory reflex is a neural circuit capable of providing information about inflammatory status of the body to the brain in real time to allow for rapid neural regulatory responses. The anatomic and physiologic basis of the inflammatory reflex is reviewed as the prototype of inflammation-regulating neural circuits as is evidence implicating this reflex in modulating clinical conditions encountered in perioperative medicine and critical care. Active areas of research into the neuroimmune interface that aim to provide new therapeutics that exploit the nervous system to control dysregulated and nonresolving inflammation are then discussed.