Effectiveness and Validity of Sonographic Upper Airway Evaluation to Predict Difficult Laryngoscopy.

OBJECTIVES: Our objective was to evaluate the effectiveness of 9 airway sonographic parameters imaged from the submandibular view as predictors of difficult laryngoscopy. Additionally, we aimed to evaluate the validity of the models of combined sonographic and clinical tests in predicting difficult laryngoscopy. METHODS: This study analyzed a sample of 199 patients who were categorized as having easy (grades 1 and 2) or difficult (grades 3 and 4) laryngoscopy during general anesthesia with endotracheal intubation based on the laryngoscopic criteria of Cormack and Lahane (Anaesthesia 1984; 39:1105-1111). Nine sonographic parameters imaged from the submandibular view, including the hyomental distance in neutral and extended positions, hyomental distance ratio, tongue cross-sectional area, tongue width, tongue volume, tongue thickness-to-oral cavity height ratio, and floor of the mouth muscle cross-sectional area and volume, were analyzed. The validity of the models encompassing combined screening tests was assessed. RESULTS: Twenty-two patients (11.1%) were categorized as having difficult laryngoscopy. Statistically significant differences between patients with difficult and easy laryngoscopy were noted for 5 of 9 parameters. The diagnostic validity profiles showed poor sensitivity (9.1%-42.9%) and positive predictive value (4.5%-66.7%), but good specificity (71.8%-97.7%) and negative predictive value (87.1%-94.5%). The combination of tests improved the diagnostic validity profile (area under the curve, 0.852). CONCLUSIONS: Sonographic predictors may help identify patients with difficult laryngoscopy. Individual measures have unsatisfactory diagnostic profiles. The models based on combined tests have improved diagnostic value.

Reliability of focused cardiac ultrasound by novice sonographer in preoperative anaesthetic assessment: an observational study.

BACKGROUND: Use of preoperative echocardiography may help to identify patients with increased cardiac risk, who may benefit from modification of perioperative plan. The objective of our study was to evaluate the reliability of preoperative focused cardiac ultrasound (FoCUS) performed by an anaesthetist with basic ultrasound training and its impact on patient's management. METHODS: The prospective observational study was conducted in 159 adult patients, scheduled for elective operations. Cardiac ultrasound was performed by one anaesthetist with a limited experience of FoCUS. A simple, mnemonic scheme was used for the final reporting of each study. The same scheme was used by a cardiologist who produced an independent report based on digital video loops stored in the machine memory. Anaesthetists in-charge made final perioperative plan. Comparative analysis of anaesthetist and cardiologist performed ultrasound report was made. The incidence of modification of initial perioperative plan resulting from FoCUS report was analyzed. RESULTS: The average time required to complete the examination was 182 s 95% CI [173-190]. Images of quality adequate to answer all questions from the scheme were obtained in 97.5% (155/159) of patients. There was strong agreement between the anaesthetist and the cardiologist in 97.8% (2274/2325) of the examined categories. In two categories (global and regional left ventricle contractility impairment) statistically significant discrepancies between both diagnosticians were confirmed (p McNemar <0.04). When compared with the cardiologist's assessment the agreement of the anesthetist's diagnosis had sensitivity of 0.84, specificity 0.99, positive predictive value 0.78 and negative predictive value 0.99. Kappa statistics showed good agreement between both examining doctors (κ = 0.797). Based on ultrasound findings, the preliminary anaesthetic plan was changed in relation to 20.8% (33/159) of patients. CONCLUSIONS: An anaesthetist with limited training in FoCUS can perform a reliable preoperative examination which alters the perioperative management.

Usability of ultrasound assessment of gastric content. Case reports.

The paper presents the use of ultrasound assessment of gastric content in anesthesiological practice. Factors influencing pulmonary aspiration of gastric content and the risk of a complication in the form of aspiration pneumonia are discussed. The examination was performed on two patients hospitalized in a state of emergency who required surgical intervention. The first patient, a 46-year-old male with a phlegmon of the foot, treated for type 2 diabetes, ischemic heart disease and renal insufficiency, required urgent incision of the phlegmon. The second patient, a 36-year-old male with a post-traumatic pericerebral hematoma, qualified for an urgent trepanation. Interviews with the patients and their medical documentation indicated that they had been fasting for the recommended six hours before the surgery. However, during a gastric ultrasound examination it was found that food was still present in the stomach, which caused a change in the anesthesiological procedure chosen. The authors present a method of performing gastric ultrasound examination, determining the nature of the food content present and estimating its volume.

Will transoesophageal echocardiography become a standard tool for anesthetists to assess haemodynamic status during non-cardiac surgeries? Case report and literature review.

A 53-year-old male, with no history of cardiovascular diseases, underwent elective extended right hemihepatectomy for large metastatic tumor. Approximately 2 hours after the start of procedure sudden onset of severe hypotension associated with profound desaturation and significant fall in end-tidal carbon dioxide pressure was noted. Transoesophageal echocardiography was performed and massive air embolism was confirmed. Patient was turned into Trendelenburg position, inspired oxygen was increased to 100% and positive end-expiratiory pressure turned up to 10 cm H20. Patient was further resuscitated with iv fluids, blood products and vasopressors under surveillance of transoesophageal echocardiography. In this report we present a case in which intraoperative use of transoesophageal echocardiography by trained anaesthetist helped to immediately identify the cause of sudden hypotension and hypoxaemia. Transoesophageal echocardiographywas also a valuable tool for direct monitoring of efficacy of instituted treatment.