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EDITOR’S PERSPECTIVE What We Already Know about This Topic Intraoperative triple-low events (mean arterial pressure less than 75 mmHg, Bispectral Index less than 45, and minimum alveolar fraction of anesthetic less than 0.8) have been found to be associated with increased risk of mortality What This Article Tells Us That Is New A randomized electronic alert of triple-low events to treating clinicians did not reduce 90-day mortality The alerts minimally influenced clinician responses, assessed as vasopressor administration or reduction in end-tidal volatile anesthetic partial pressure, and there was no association between response to alerts and mortality Triple-low events predict mortality but do not appear to be causally related Background Triple-low events (mean arterial pressure less than 75 mmHg, Bispectral Index less than 45, and minimum alveolar fraction less than 0.8) are associated with mortality but may not be causal. This study tested the hypothesis that providing triple-low alerts to clinicians reduces 90-day mortality. Methods Adults having noncardiac surgery with volatile anesthesia and Bispectral Index monitoring were electronically screened for triple-low events. Patients having triple-low events were randomized in real time, with clinicians either receiving an alert, “consider hemodynamic support,” or not. Patients were blinded to treatment. Helpful responses to triple-low events were defined by administration of a vasopressor within 5 min or a 20% reduction in end-tidal volatile anesthetic concentration within 15 min. Results Of the qualifying patients, 7,569 of 36,670 (20%) had triple-low events and were randomized. All 7,569 were included in the primary analysis. Ninety-day mortality was 8.3% in the alert group and 7.3% in the nonalert group. The hazard ratio (95% CI) for alert versus nonalert was 1.14 (0.96, 1.35); P = 0.12, crossing a prespecified futility boundary. Clinical responses were helpful in about half the patients in each group, with 51% of alert patients and 47% of nonalert patients receiving vasopressors or having anesthetics lowered after start of triple low (P < 0.001). There was no relationship between the response to triple-low events and adjusted 90-day mortality. Conclusions Real-time alerts to triple-low events did not lead to a reduction in 90-day mortality, and there were fewer responses to alerts than expected. However, similar mortality with and without responses suggests that there is no strong relationship between responses to triple-low events and mortality.

Triple-low events (mean arterial pressure less than 75 mmHg, Bispectral Index less than 45, and minimum alveolar fraction less than 0.8) are associated with mortality but may not be causal. This study tested the hypothesis that providing triple-low alerts to clinicians reduces 90-day mortality.Adults having noncardiac surgery with volatile anesthesia and Bispectral Index monitoring were electronically screened for triple-low events. Patients having triple-low events were randomized in real time, with clinicians either receiving an alert, "consider hemodynamic support," or not. Patients were blinded to treatment. Helpful responses to triple-low events were defined by administration of a vasopressor within 5 min or a 20% reduction in end-tidal volatile anesthetic concentration within 15 min.Of the qualifying patients, 7,569 of 36,670 (20%) had triple-low events and were randomized. All 7,569 were included in the primary analysis. Ninety-day mortality was 8.3% in the alert group and 7.3% in the nonalert group. The hazard ratio (95% CI) for alert versus nonalert was 1.14 (0.96, 1.35); P = 0.12, crossing a prespecified futility boundary. Clinical responses were helpful in about half the patients in each group, with 51% of alert patients and 47% of nonalert patients receiving vasopressors or having anesthetics lowered after start of triple low (P0.001). There was no relationship between the response to triple-low events and adjusted 90-day mortality.Real-time alerts to triple-low events did not lead to a reduction in 90-day mortality, and there were fewer responses to alerts than expected. However, similar mortality with and without responses suggests that there is no strong relationship between responses to triple-low events and mortality.

Recent advances in surgical and interventional procedures have led to a significant and increased demand for anesthesia services in locations distant from the traditional operating room. Special settings such as ophthalmologic surgery, interventional radiology, and the electrophysiology lab present unique challenges to the anesthesia provider. In addition to the remote location of the procedure rooms, the lack of familiarity with the equipment and distance from emergency back-up make for a challenging situation. Judicious preparation and set up of anesthesia equipment and materials as well as communication between the anesthesiologist, proceduralist, technicians, and nursing staff are key to performing these procedures in a safe fashion. Finally, procedures involving radiation exposure require awareness of occupational and patient safety concerns. This chapter discusses relevant anesthetic considerations for interventions performed in special settings including ophthalmologic surgery, gastrointestinal endoscopy, interventional radiology, cardiac diagnostic, and magnetic resonance imaging suites.

The preanesthesia evaluation usually occurs when the anesthesia provider first meets a patient scheduled for a surgical intervention. The importance of the preanesthesia evaluation must be underscored as it represents the foundation for the anesthetic plan. A continuum of care that starts with the initial assessment and ends with the complete recovery of the surgical patient requires intervention by the anesthesiologist as a perioperative physician. Moreover, the anesthesiologist is both the patient’s advocate and the leader of the perioperative pathway. This chapter focuses on the rational use of screening tools and resources to evaluate patients as well as risk stratification based on a systematic approach that includes a careful assessment of the various organ systems for a planned procedure. The relevance of the informed consent process and documentation as well as the elements of preanesthesia evaluation in special circumstances are also addressed.

Functional endoscopic sinus surgery is among the most challenging of ENT procedures for a variety of reasons including the need for immobility, hemostasis, and, especially, gentle emergence from anesthesia. Anesthesiologists have contributed significantly, using anesthetic techniques to mitigate intraoperative hemorrhage into the surgical field, thus significantly improving visualization of the surgical field. Functional endoscopic sinus surgery (FESS) strives to enable direct examination in situ with subsequent correction of encountered chronic changes and barriers which limit sinus drainage and aeration. The use of supraglottic airway (SGA) over endotracheal tubes (ETT) appears additionally advantageous, providing reduced incidence and severity of coughing intraoperatively and during emergence. Propofol/remifentanil total intravenous anesthesia (TIVA) with spontaneous respiration (PRTSR) is considered by some an optimal strategy to avoid emergence problems and provide flexibility, and minimize nausea, vomiting, and estimated blood loss (EBL), while ensuring rapid induction and emergence.

Study Objective To evaluate the effectiveness of the CTrach Laryngeal Mask Airway (LMA) when used electively. Design Retrospective analysis. Setting Operating room of an academic hospital. Measurements Data from 126 patients who were electively intubated with the CTrach LMA over a 16-month period were reviewed. Each patient's weight, height, ASA physical status classification, Mallampati score, thyromental distance, and cervical spine range of motion were recorded. Main Results Successful ventilation was achieved in 100% of patients, while successful intubation was achieved in 89.7% of patients. The most common reason for failure to intubate was poor airway visualization and the inability to appropriately position the device anterior to the vocal cords. Conclusions The major advantage of the CTrach LMA is that it is the only device that allows airway visualization during patient ventilation; however, it does not have 100% success with intubation.

Improvements in airway imaging technology provide the potential for an improved understanding of airway pathology and upper airway mechanics. We present here a preliminary report on the applicability of cone beam computed tomography technology in conjunction with multidimensional digital analysis for the purposes of clinical airway management. The use of this technology for airway imaging in anesthesiology has not been reported. Traditional skeletal and soft tissue images as well as distance and volume measurements were obtained without difficulty. Three-dimensional image reconstructions as well as "virtual laryngoscopy" were achieved with resulting excellent image quality, suggesting a broad range of possibilities for upper airway examination and analysis. A modified Muller test with volumetric rendering of the airway passages under baseline and negative pressure conditions was also performed, made possible as a result of the system's short (9 s) scanning times. We believe that cone beam computed tomography technology offers an additional dimension to airway evaluation that has considerable potential.