Coagulopathy Management of an Acute Type A Aortic Dissection in a Patient Taking Apixaban.

This paper reports the successful management of a patient with acute type A Penn B thoracic aortic dissection who was on apixaban therapy for atrial fibrillation. Emergency surgery was performed due to the patient's clinical deterioration, with innominate artery compromise and severe aortic valve regurgitation. The anesthesia team used point-of-care rotational thromboelastometry-guided coagulation replacement therapy consisting of prothrombin concentrate, fibrinogen, and platelets. The surgical team used a complementary approach with topical hemostatic agents and a pericardial patch. No additional blood products were required. The patient recovered fully and was discharged home.

Survey of the Preparation of Cardiovascular Emergency Medications for Adult Cardiovascular Anesthesia.

OBJECTIVES: To describe current practices and safety concerns regarding cardiac emergency medications in cardiac anesthesia. DESIGN: An anonymous survey with multiple-choice questions. SETTINGS: Online survey using Opinio platform. PARTICIPANTS: Cardiac anesthesiologists from United States and Canada. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Response rate was 12% (n = 320), with 78% of respondents from the United States and 22% from Canada. The majority of the respondents were experienced (66%), academic (60%), and worked in large cardiac institutions (81%). Most cardiac emergency medications were prepared in the operating room (53.4%), followed by the pharmacy (34%) and industry (8.2%). American respondents had more medications prepared by a pharmacy (53%) versus Canadian (10%, p < 0.001). The majority (85%) considered expiration time of cardiac medications prepared in the operating room to be more than 12 hours. Familiarity with the American Society of Anesthesiologists guidelines on labeling was 58%, other medication safety guidelines 25%, and 34% were not familiar with any guidelines. The majority used color-coded labeling (95%), and a minority (11%) used bar-code systems. Most respondents (69%) agreed that lack of availability of preprepared medications could compromise patient safety. Having to prepare medications by themselves was a concern for respondents based on distractions (66%), lack of availability for emergencies (53%), labeling errors (41%), incorrect concentration (36%), sterility (33%), and stability (30%). CONCLUSION: This survey found that cardiac emergency medications commonly are prepared in the operating room. The authors identified gaps in familiarity with parenteral medications safety guidelines. Most safety concerns could be addressed with the application of current medication safety guidelines.

Valve Failure in the Gas Monitor: An Unusual Cause of Falsely Low Capnography Values Under General Anesthesia: A Case Report.

We present a case in which the Dräger Primus (Dräger Medical AG&Co KG, Lüberck, Germany) anesthesia monitor displayed false readings of low end-tidal carbon dioxide (EtCO2) immediately after intubation. The patient's physical examination, vital signs, and arterial blood gases were normal. The ventilator, circuit, gas sample line, and water trap appeared intact and functional. A second gas analyzer revealed normal EtCO2 readings, correlating with blood gas values. The defective monitor gas flow rates and gas calibration values were inappropriately low. Partial opening of the solenoid zero valve allowed entrainment of room air, which caused artifactual dilution of the gas sample.

Diagnostic Accuracy of Neuromonitoring for Identification of New Neurologic Deficits in Pediatric Spinal Fusion Surgery.

BACKGROUND: Intraoperative neuromonitoring (IONM) modalities, transcranial motor-evoked potentials (TcMEPs), and somatosensory-evoked potentials (SSEPs) are accepted methods to identify impending spinal cord injury during spinal fusion surgery. Debate exists over sensitivity and specificity of these modalities. Our purpose was to measure the incidence of new neurologic deficits (NNDs) and estimate sensitivity and specificity of IONM modalities. METHODS: Institutional Ethics Board approval was obtained to review charts of patients younger than 22 years undergoing scoliosis surgery from 2007 to 2014 retrospectively. The definition of true-positive patients included two subgroups: (1) patients with an IONM alert, which did not resolve despite the interventions and had a NND postoperatively; or (2) patients with an IONM alert triggering interventions and the alert resolved with no NND postoperatively. Subgroup 2 of the definition is debatable; thus, we performed a multiple sensitivity analysis with three assumptions. Assumption 1: without interventions, all such patients would have experienced NNDs (assumption used in previous studies); Assumption 2: without intervention, half of these patients would have experienced NNDs; Assumption 3: without intervention, none of these of patients would have experienced NNDs. RESULTS: We included 296 patients. Patients with incomplete charts (n = 3), no IONM monitoring (n = 11), and inadequate baseline IONM (n = 7) were excluded. The incidence of NND was 3.7% (95% confidence interval, 2.1%-6.5%). Successful IONM in at least one modality was obtained in 275 patients (92.9%), of whom 268 (97.5%) and 259 (94.2%) had successful baseline TcMEP or SSEP signals, respectively. Fifty-one (17%) patients had IONM alerts, 41 were only TcMEP, 5 were only SSEP, and 5 were in both modalities. After interventions, 42 (82%) patients recovered, 41 had no NND (true-positive under Assumption (1), but one developed a NND (false-negative). Of the 9 patients with no alert recovery, 6 had a NND (true-positive) and 3 did not (false-positives). Of the remaining 224 patients with no alerts, 221 had no NND (true-negatives) and 3 did (false-negatives). Sensitivity was estimated to be 93.5%, 92.2%, and 46.7% for TcMEPs, combination (either TcMEPs or SSEPs), and SSEPs, respectively. Multiple sensitivity analysis demonstrated that sensitivity and specificity vary markedly with different assumptions. CONCLUSION: TcMEPs are more sensitive than SSEP at detecting an impending NND. IONM modalities are highly specific. Both sensitivity and specificity are impacted substantially by assumptions of the impact of interventions on alerts and NND. Properly designed, controlled, multicenter studies are required to establish diagnostic accuracy of IONM in scoliosis surgery.

The impact of pneumoperitoneum and Trendelenburg positioning on respiratory system mechanics during laparoscopic pelvic surgery in children: a prospective observational study.

PURPOSE: The aim of this study was to describe the changes in respiratory system compliance and other measures of respiratory mechanics associated with peritoneal insufflation (12 mmHg pressure) with carbon dioxide (PNP12) and 20° Trendelenburg positioning (TDG20) in pediatric patients undergoing laparoscopic surgery for abdominal cryptorchidism. METHODS: Twelve subjects with abdominal cryptorchidism undergoing orchiopexy were enrolled in the study. General anesthesia was conducted with sevoflurane/O2/air, fentanyl, and rocuronium. Pressure-controlled ventilation with a peak inspiratory pressure (PIP) of 10-15 cm H2O and a positive end-expiratory pressure of 5 cm H2O was titrated to achieve a tidal volume (VT/kg) of 6-10 mL·kg(-1) and end-tidal carbon dioxide (EtCO2) of 35-40 mmHg. Adjustments of PIP and respiratory rate (RR) were made to maintain the initial VT/kg and EtCO2 < 50 mmHg. Measurements of weight-corrected dynamic compliance (Cdyn/kg), VT/kg, and EtCO2 were recorded at baseline, after PNP12, at TDG20, and again after deflation and return to the level position. RESULTS: Adjustments in PIP were required in all subjects to maintain the target VT/kg. The Cdyn/kg decreased 42% (95% confidence interval [CI]: 30 to 51; P < 0.001) after PNP12, and it remained below baseline until deflation. The TDG20 caused only minimal additional reductions in Cdyn/kg (10% decrease; 95% CI: 0 to 19; P = 0.048). The VT/kg decreased 42% (95% CI: 31 to 52; P = 0.048) with PNP12, and after TDG20, it decreased a further 10% (95% CI: 4 to 19; P = 0.038). After deflation, the VT/kg increased by 56% (95% CI: 28 to 90; P = 0.001) and was then adjusted back to the initial values. CONCLUSION: The PNP12 significantly decreases Cdyn/kg and VT/kg in pediatric patients. The use of TDG20 produces a relatively minor additional impact in respiratory mechanics. This study emphasizes the need to adjust ventilator settings to maintain normal gas exchange during this procedure.

"GIOSAT": a tool to assess CanMEDS competencies during simulated crises.

PURPOSE: Our objective was to develop and evaluate a Generic Integrated Objective Structured Assessment Tool (GIOSAT) to integrate Medical Expert and intrinsic (non-medical expert) CanMEDS competencies with non-technical skills for crisis simulation. METHODS: An assessment tool was designed and piloted using two pediatric anesthesia scenarios (laryngospasm and hyperkalemia). Following revision of the tool, we used previously recorded videos of anesthesia residents (n = 50) who managed one of two intraoperative advanced cardiac life support (ACLS) scenarios (ventricular tachycardia or ventricular fibrillation). Four independent trained raters, blinded to the residents' level of training, analyzed the video recordings using the GIOSAT scale. Inter-rater reliability was calculated using intraclass correlations (ICCs) for single raters (single measure) and the average of the four raters (average measure), and construct validity was investigated by correlating GIOSAT scores with postgraduate year of residency (PGY). RESULTS: Total GIOSAT scores for the ACLS scenarios had single measure ICCs of 0.62 and average measure ICCs of 0.85. Inter-rater reliability was substantial for both Medical Expert and intrinsic competencies (single measure ICCs 0.69 and 0.62, respectively; average measure ICCs 0.90 and 0.82, respectively). We found significant correlations between PGY level and total GIOSAT score (r = 0.36; P = 0.011) and between PGY level and Medical Expert competencies (r = 0.42; P = 0.003); however, correlations were not found between PGY level and intrinsic CanMEDS competencies (r = 0.24; P = 0.09). CONCLUSION: Inter-rater reliability of the total GIOSAT scores using four trained raters was substantial. Significant correlation between PGY and (i) total GIOSAT score and (ii) Medical Expert competencies supports construct validity. Evidence of validity was not obtained for intrinsic CanMEDS competencies.

Continuous lumbar transversus abdominis plane block may spread to supraumbilical dermatomes.

PURPOSE: The transversus abdominis plane block is an interfascial block intended to target nerves supplying the abdominal wall. It has been shown to reduce pain and postoperative opioids in abdominal surgeries. We present the case of a high-risk patient in whom bilateral continuous lumbar transversus abdominis plane blocks provided effective postoperative analgesia following infraumbilical midline laparotomy. CLINICAL FEATURES: A 59-yr-old woman with coronary artery disease, severe peripheral vascular disease, and mild to moderate obstructive sleep apnea underwent a total abdominal hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymph node dissection via an infraumbilical midline laparotomy. Bilateral ultrasound-guided lumbar transversus abdominis plane blocks with catheters were sited intraoperatively. Using only a continuous local anesthetic infusion in the postoperative period, the patient required no systemic opioids or acetaminophen for 81 hr. A sensory block level of T6-L1, higher than that reported following a single-shot technique, remained for 24 hr following infusion discontinuation and finally normalized after 33 hr. CONCLUSIONS: Lumbar transversus abdominis plane blocks with continuous infusions may offer an effective alternative to epidural blockade and systemic opioids in high-risk patients. Additionally, given the extensive somatosensory block, this technique may have an analgesic role following abdominal incisions involving not only the infraumbilical region but also supraumbilical sites.

A transesophageal echocardiography examination clarifies the cause of cardiovascular collapse during scoliosis surgery in a child.

PURPOSE: The prone position is required for posterior spinal fusion surgery and may be associated with cardiovascular changes, including a decrease in venous return and cardiac index. We report a case of a patient who developed cardiovascular collapse, increased central venous pressure (CVP), and massive bleeding during posterior spinal fusion surgery. A transesophageal echocardiography examination (TEE) documented a right ventricular outflow tract (RVOT) obstruction associated with the use of transverse bolsters. CLINICAL FEATURES: We describe a case of a healthy 14-yr-old male with idiopathic scoliosis who developed severe intraoperative cardiovascular instability and massive bleeding. The surgery was suspended, and the patient was transferred to the intensive care unit. The patient subsequently underwent TEE in the supine and prone positions. The echocardiogram appeared normal in the supine position; however, in the prone position with transverse bolsters, we identified a significant decrease in the diameter of the RVOT that worsened with pressure applied against the thoracic spine. The central venous pressure increased from 10-24 mmHg simultaneously. We found appreciably less impact to the RVOT, RV size and flow, and CVP (10 to 14 mmHg) using longitudinal bolsters both with and without pressure to the back. This position was recommended for the patient's reoperation, which was uneventful. CONCLUSION: A TEE confirmed a RVOT obstruction in the prone position that was associated, in this case, with the use of transverse bolsters. The RVOT obstruction was explained by the chest deformity, compliant chest cage, bolstering, and pressure applied to the patient's back by the surgeon. This positional RVOT obstruction may explain the increase in the CVP and the secondary massive bleeding during the first operation. The TEE was useful to diagnose the patient's condition and to guide his positioning for the second operation.

Case report: management of immediate post-cardiopulmonary bypass massive intra-cardiac thrombosis.

PURPOSE: To describe the management of severe acute intracardiac thrombosis in a patient who underwent redo multiple valve replacement and valvular repair. The diagnostic features, associated risk factors, and anesthetic management are reviewed. CLINICAL FEATURES: A 67-yr-old woman undergoing redo mitral and aortic mechanical valve replacement and tricuspid annuloplasty under aprotinin prophylaxis exhibited severe refractory hypotension that began immediately after protamine reversal of intraoperative heparin anticoagulation following separation from cardiopulmonary bypass. Intraoperative transesophageal echocardiography revealed severe thrombosis in the right atrium, right ventricle and pulmonary artery. The patient was managed by immediate reheparinization and return to cardiopulmonary bypass (CPB), surgical thrombectomy, and intraoperative administration of recombinant tissue-plasminogen activator. After removal of the thrombi, and separation from CPB, no further protamine was given. One hundred units of blood products and two surgical re-explorations were required to manage subsequent massive postoperative bleeding. Acute heparin-induced thrombocytopenia (HIT) was ruled out using sensitive assays for HIT antibodies. After 16 days in the intensive care unit and 30 more days in hospital, the patient was subsequently transferred to a chronic care facility and succumbed several weeks later. CONCLUSION: Acute intraoperative thrombosis is a rare and potentially fatal complication of cardiac surgery. Intraoperative transesophageal echocardiography was essential for rapid diagnosis in this case. Multiple interacting prothrombotic factors (e.g., aprotinin use, acquired antithrombin deficiency, long pump time, post-protamine status, transfusion of blood components) were likely contributing factors related to this rare complication.

Ventilación mecánica dirigida a objetivos

La ventilación es un soporte vital avanzado moderno que ha evolucionado en los últimos años, desde el voluminoso ventilador de presiones negativas o "pulmón de hierro" de principios de siglo, hasta los ventiladores procesados por computador con diferentes posibilidades de terapia. Estos se clasifican de acuerdo al sistema que los cical, en ventiladores de presión, de volumen o de tiempo. Los ventiladores modernos permiten una combinación de diferentes modos y terapias ventilatorias. La instauración de la ventilación mecánica debe hacerse juzgando el riesgo con el beneficio y teniendo objetivos claros. Aunque en los últimos años se han deescrito diferentes formas de manipulación de la terapía ventilatoria, los métodos convencionales como la Ventilación Mandatoria Controlada (CMV, del inglés Controlled Mandatory Ventilation), la Ventilación Mandatoria Intermitente Sincronizada (SIMV, del inglés Synchronized Intermitent Mandatory Ventilation), la Presión Positiva al Final de Espiración (PEEP), del inglés Positive End Espiratory Pressure) y el Soporte de Presión Ventilatoria (PSV, del inglés Pressure Support Ventilation) siguen siendo los modos más utilizados. El modo controlado debe limitarse al mínimo tiempo posible, pasando al paciente a modos asistidos con la mayor brevedad. La ventilación mandatoria intermitente sincrozada sigue siendo el modo de retiro progesivo más empleado, especialmente en combinación con el soporte de presión