Overview and Limitations of Database Research in Anesthesiology: A Narrative Review.

The utilization of large-scale databases for research in medical fields, including anesthesiology, has increased in popularity over the last decade, likely due to their structured content and relative ease of access. These databases have been used in a variety of perioperative studies, including analyses of risk stratification, preoperative testing, complications, and cost. While these databases contain a wealth of information that allows for an abundance of research opportunities, there are unique limitations to their use. A comprehensive understanding will afford the anesthesiology researcher the knowledge and tools to not only better interpret studies that utilized these databases, but also to conduct analyses of their own. This review details the content and composition of these databases, highlights the advantages of and limitations to their use, and offers information about their access and cost.

Differential Ventilation Using Flow Control Valves as a Potential Bridge to Full Ventilatory Support during the COVID-19 Crisis.

BACKGROUND: During the COVID-19 pandemic, ventilator sharing was suggested to increase availability of mechanical ventilation. The safety and feasibility of ventilator sharing is unknown. METHODS: A single ventilator in pressure control mode was used with flow control valves to simultaneously ventilate two patients with different lung compliances. The system was first evaluated using high-fidelity human patient simulator mannequins and then tested for 1 h in two pairs of COVID-19 patients with acute respiratory failure. Patients were matched on positive end-expiratory pressure, fractional inspired oxygen tension, and respiratory rate. Tidal volume and peak airway pressure (PMAX) were recorded from each patient using separate independent spirometers and arterial blood gas samples drawn at 0, 30, and 60 min. The authors assessed acid-base status, oxygenation, tidal volume, and PMAX for each patient. Stability was assessed by calculating the coefficient of variation. RESULTS: The valves performed as expected in simulation, providing a stable tidal volume of 400 ml each to two mannequins with compliance ratios varying from 20:20 to 20:90 ml/cm H2O. The system was then tested in two pairs of patients. Pair 1 was a 49-yr-old woman, ideal body weight 46 kg, and a 55-yr-old man, ideal body weight 64 kg, with lung compliance 27 ml/cm H2O versus 35 ml/cm H2O. The coefficient of variation for tidal volume was 0.2 to 1.7%, and for PMAX 0 to 1.1%. Pair 2 was a 32-yr-old man, ideal body weight 62 kg, and a 56-yr-old woman, ideal body weight 46 kg, with lung compliance 12 ml/cm H2O versus 21 ml/cm H2O. The coefficient of variation for tidal volume was 0.4 to 5.6%, and for PMAX 0 to 2.1%. CONCLUSIONS: Differential ventilation using a single ventilator is feasible. Flow control valves enable delivery of stable tidal volume and PMAX similar to those provided by individual ventilators.

Patient injuries from anesthesia gas delivery equipment: a closed claims update.

BACKGROUND: Improvements in anesthesia gas delivery equipment and provider training may increase patient safety. The authors analyzed patient injuries related to gas delivery equipment claims from the American Society of Anesthesiologists Closed Claims Project database over the decades from 1970s to the 2000s. METHODS: After the Institutional Review Board approval, the authors reviewed the Closed Claims Project database of 9,806 total claims. Inclusion criteria were general anesthesia for surgical or obstetric anesthesia care (n = 6,022). Anesthesia gas delivery equipment was defined as any device used to convey gas to or from (but not involving) the airway management device. Claims related to anesthesia gas delivery equipment were compared between time periods by chi-square test, Fisher exact test, and Mann-Whitney U test. RESULTS: Anesthesia gas delivery claims decreased over the decades (P < 0.001) to 1% of claims in the 2000s. Outcomes in claims from 1990 to 2011 (n = 40) were less severe, with a greater proportion of awareness (n = 9, 23%; P = 0.003) and pneumothorax (n = 7, 18%; P = 0.047). Severe injuries (death/permanent brain damage) occurred in supplemental oxygen supply events outside the operating room, breathing circuit events, or ventilator mishaps. The majority (85%) of claims involved provider error with (n = 7) or without (n = 27) equipment failure. Thirty-five percent of claims were judged as preventable by preanesthesia machine check. CONCLUSIONS: Gas delivery equipment claims in the Closed Claims Project database decreased in 1990-2011 compared with earlier decades. Provider error contributed to severe injury, especially with inadequate alarms, improvised oxygen delivery systems, and misdiagnosis or treatment of breathing circuit events.

The safety and efficacy of regional anesthesia in an office-based setting.

STUDY OBJECTIVE: To determine the safety and efficacy of regional anesthesia techniques when administered in the office-based setting. DESIGN: Retrospective chart review. SETTING: Free-standing orthopedic office with an operating room suite. MEASUREMENTS: A total of 238 patients underwent 242 anesthetics. Types of anesthetics delivered were quantified. Regional anesthetics were further divided into specific nerve blocks. Times from anesthetic start to surgical start and from surgical end to anesthetic end were calculated. Adverse outcomes were ascertained and followed. MAIN RESULTS: Of the 242 anesthetics administered, 123 were peripheral nerve blocks, two were neuraxial blocks, 140 were monitored anesthesia care cases, and 17 were general anesthetics (14 Laryngeal Mask Airway cases, two mask ventilation cases, and one endotracheal intubation). The average times from anesthesia start to surgery start were as follows: monitored anesthesia cases, 19+/-7 min (median, 20 min); regional anesthesia cases, 29+/-11 min (median, 30 min); and general anesthesia cases, 31+/-11 min (median, 30 min). The average time from surgery end to anesthesia end for monitored anesthesia cases was 9+/-3 min (median, 10 min); regional anesthesia, 9+/-3 min (median, 10 min); and general anesthesia, 12+/-4 min (median, 20 min). Two transient nerve injuries occurred, both of which resolved. CONCLUSIONS: On the basis of our experience, we believe that regional anesthesia can be delivered efficiently and safely for orthopedic procedures in the office-based environment, and we encourage its wider use.

Anesthetic implications of myasthenia gravis.

Myasthenia gravis is a disease of great significance to the anesthesiologist, because it affects the neuromuscular junction. Many patients with this condition are treated by surgical thymectomy, using techniques developed by Mount Sinai physicians, including Dr. Paul Kirschner, Dr. Alan E. Kark, and the late Dr. Angelos E. Papatestas. The authors review the anesthetic considerations in the management of patients with myasthenia gravis who are undergoing thymectomy and other surgical procedures.

Forehead pulse oximeter-associated pressure injury.

Peripherally placed transmittance pulse oximeter sensors have been associated with patient injury including burns, gangrene, and necrosis. There are 2 reports of burn injuries associated with the use of forehead reflectance sensors, but there is no report of a pressure injury associated with the use of an OxiMax™ MAX-FAST™ forehead sensor and headband. We report the case of a patient who developed tissue necrosis associated with prolonged application of a forehead pulse oximeter sensor under a headband and displacement of the sensor cable.

Severe anaphylactoid reaction to thymoglobulin in a pediatric renal transplant recipient.

Intraoperative administration of thymoglobulin is an integral part of the anti-rejection regimen during organ transplantation. However, its administration may be associated with complications. An anaphylactoid reaction that occurred in a pediatric recipient of a living-related renal transplant, on initiating an intravenous infusion of thymoglobulin, is presented.