Hypernatremia-A Manifestation of COVID-19: A Case Series.

We report for the first time therapy-resistant hypernatremia (plasma sodium concentration ≥150 mmol per liter) developing in 6 of 12 critically ill coronavirus disease 2019 (COVID-19) patients age 57-84 years requiring mechanical ventilation. There was no correlation between plasma sodium concentrations and sodium input. Plasma concentrations of chloride were elevated, those of potassium decreased. These findings are consistent with abnormally increased renal sodium reabsorption, possibly caused by increased angiotensin II activity secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced downregulation of angiotensin-converting enzyme 2 (ACE2) receptors. As hypernatremia was associated with increased length of intensive care unit stay, special attention should be paid to the electrolyte status of COVID-19 patients.

[Intrahepatic Hematoma and Pulmonary Embolism in a Young Woman with Oral Contraceptives Complicated by Type II Heparin Induced Thrombocytopenia Requiring ECMO-Therapy: a Case Report]. / Fulminante Lungenarterienembolie bei heparininduzierter Thrombozytopenie Typ II.

A 46-year-old woman on oral contraceptives developed an intrahepatic hematoma due to a benign hepatic tumor. As an incidental finding, a computed tomography showed a pulmonary embolism. Unfractionated heparin was given in a prophylactic dosing in an attempt to balance the risk of further intrahepatic bleeding with that of thrombosis. Ten days later, the patient developed a second pulmonary embolism along with acute right heart failure requiring cardiopulmonary resuscitation. As a sufficient circulation and oxygenation could not be reestablished, a veno-arterial extracorporeal membrane oxygenation (ECMO) was installed. An ELISA-Test, detecting PF4-Heparin associated antibodies, resulted in a positive result for a type II heparin induced thrombocytopenia even in the absence of thrombocytopenia. After hemodynamic and pulmonary stabilization, six days after ECMO-support the cannula was scheduled to be removed. On removal of the venous cannula the patient developed another massive pulmonary embolism with cardiac arrest which led to immediate reinstallation of va-ECMO. Under therapeutic anticoagulation using argatroban the ECMO support continued until the patient was on day 17 successfully weaned.

Perceived barriers to computerised quality documentation during anaesthesia: a survey of anaesthesia staff.

BACKGROUND: Underreporting of intraoperative events in anaesthesia is well-known and compromises quality documentation. The reasons for such omissions remain unclear. We conducted a questionnaire-based survey of anaesthesia staff to explore perceived barriers to reliable documentation during anaesthesia. METHODS: Participants anonymously completed a paper-based questionnaire. Predefined answers referred to potential barriers. Additional written comments were encouraged. Differences between physician and nurse anaesthetists were tested with t-tests and chi-square tests. RESULTS: Twenty-five physician and 30 nurse anaesthetists (81% of total staff) completed the survey. The reported problems referred to three main categories: (I) potential influences related to working conditions and practices of data collection, such as premature entry of the data (indicated by 85% of the respondents), competing duties (87%), and interfering interruptions or noise (67%); (II) problems referring to institutional management of the data, for example lacking feedback on the results (95%) and lacking knowledge about what the data are used for (75%); (III) problems related to specific attitudes, e.g., considering these data not useful for quality improvement (47%). Physicians were more sceptical than nurses regarding the relevance of these data for quality and patient safety. CONCLUSIONS: The common perceived difficulties reported by physician and nurse anaesthetists resemble established barriers to incident reporting and may similarly act as barriers to quality documentation during anaesthesia. Further studies should investigate if these perceived obstacles have a causal impact on quality reporting in anaesthesia. TRIAL REGISTRATION: ClinicalTrials.gov identifier is NCT01524484. Registration date: January 21, 2012.

Comparison of Bullard and Airtraq laryngoscopes with conventional laryngoscopy in a manikin study of simulated difficult intubation.

BACKGROUND: When airway management is difficult, various measures can be taken to facilitate tracheal intubation. The Bullard and Airtraq laryngoscopes were developed for this purpose. We hypothesised that the Bullard and Airtraq laryngoscopes would perform better than a conventional laryngoscope in the management of a simulated difficult airway. We also hypothesised that the indirect laryngoscopes would perform comparably. METHODS: In a randomised controlled study, 60 anaesthetists (30 with no or little experience and 30 with broader experience in the use of the Bullard laryngoscope, referred to as beginners and experts, respectively) performed three successive intubation attempts using conventional, Bullard and Airtraq laryngoscopes in two simulated difficult airway scenarios: neck immobilisation (scenario A) and neck immobilisation with additional tongue oedema (scenario B). The primary endpoint was overall intubation success rate. Secondary endpoints were time required for successful intubation, the amount of dental stress exerted during laryngoscopy and satisfaction with each airway device. RESULTS: In scenario A, intubation success rates were 97-100% with all devices. In scenario B, all participants failed to intubate the trachea using the conventional laryngoscope. When using the Bullard laryngoscope, intubation success rates of 87-97% did not differ significantly (P > 0.05) from those during scenario A and between groups (beginners vs. experts). In contrast, when using the Airtraq laryngoscope, the overall intubation success rate was significantly lower (P < 0.05) compared with scenario A and compared with use of the Bullard laryngoscope, and differed between beginners and experts (20 and 50%, respectively). In cases of successful intubation, intubation times were comparable between devices and groups. Intubation times were longer during scenario B. Dental stress was always lower (P < 0.05) during use of the Bullard and Airtraq laryngoscopes compared with the conventional laryngoscope, lowest (P < 0.05) during use of the Bullard laryngoscope and (with the exception of use of the conventional laryngoscope by the experts) higher during scenario B than during scenario A. In scenario A, participants preferred both video laryngoscopes to the conventional laryngoscope. CONCLUSION: In a moderately difficult airway scenario, all laryngoscopes performed equally well. However, in a more difficult airway scenario, the Bullard and Airtraq laryngoscopes performed better than the conventional laryngoscope, with the Bullard device performing better than the Airtraq. This may be in part related to differing prior experiences of operators with the respective airway devices.

A minor wound with a fatal course.

The authors report on a fatal case of severe tetanus in a 74-year old woman. Despite comprehensive intensive care management they could not achieve a satisfying control of the autonomic dysfunction caused by tetanus. By now there is no established therapy for the treatment of the autonomic dysfunction. This report demonstrates the dismal prognosis of severe tetanus in the older people, which is often complicated by cardiovascular comorbidity and underlines the importance of tetanus prevention by sufficient vaccination.

Accuracy of automatic tube compensation in new-generation mechanical ventilators.

OBJECTIVE: To compare performance of flow-adapted compensation of endotracheal tube resistance (automatic tube compensation, ATC) between the original ATC system and ATC systems incorporated in commercially available ventilators. DESIGN: Bench study. SETTING: University research laboratory. SUBJECTS: The original ATC system, Dräger Evita 2 prototype, Dräger Evita 4, Puritan-Bennett 840. INTERVENTIONS: The four ventilators under investigation were alternatively connected via different sized endotracheal tubes and an artificial trachea to an active lung model. Test conditions consisted of two ventilatory modes (ATC vs. continuous positive airway pressure), three different sized endotracheal tubes (inner diameter 7.0, 8.0, and 9.0 mm), two ventilatory rates (15/min and 30/min), and four levels of positive end-expiratory pressure (0, 5, 10, and 15 cm H2O). MEASUREMENTS AND MAIN RESULTS: Performance of tube compensation was assessed by the amount of tube-related (additional) work of breathing (WOBadd), which was calculated on the basis of pressure gradient across the endotracheal tube. Compared with continuous positive airway pressure, ATC reduced inspiratory WOBadd by 58%, 68%, 50%, and 97% when using the Evita 4, the Evita 2 prototype, the Puritan-Bennett 840, and the original ATC system, respectively. Depending on endotracheal tube diameter and ventilatory pattern, inspiratory WOBadd was 0.12-5.2 J/L with the original ATC system, 1.5-28.9 J/L with the Puritan-Bennett 840, 10.4-21.0 J/L with the Evita 2 prototype, and 10.1-36.1 J/L with the Evita 4 (difference between each ventilator at identical test situations, p <.025). Expiratory WOBadd was reduced by 5%, 26%, 1%, and 70% with the Evita 4, the Evita 2 prototype, the Puritan-Bennett 840, and the original ATC system, respectively. The expiratory WOBadd caused by an endotracheal tube of 7.0 mm inner diameter was 5.5-42.2 J/L at a low ventilatory rate and 19.6-82.3 J/L at a high ventilatory rate. It was lowest with the original ATC system and highest with the Evita 4 ventilator (p <.025). CONCLUSIONS: Flow-adapted tube compensation by the original ATC system significantly reduced tube-related inspiratory and expiratory work of breathing. The commercially available ATC modes investigated here may be adequate for inspiratory but probably not for expiratory tube compensation.

Intratidal compliance-volume curve as an alternative basis to adjust positive end-expiratory pressure: a study in isolated perfused rabbit lungs.

OBJECTIVE: Repeated collapse and reopening of alveoli have been shown to aggravate lung injury, which could be prevented by positive end-expiratory pressure (PEEP). Yet, how to adjust optimum PEEP is a matter of debate. We suggest a new strategy to adjust PEEP, which is based on the analysis of the intratidal compliance-volume curve. This approach was compared with a strategy based on the static pressure-volume curve. Furthermore, two other ventilator settings were investigated. One served as a negative control likely to provoke atelectasis, and the other was expected to induce overdistension. DESIGN: Prospective, randomized block design. SETTING: Laboratory. SUBJECTS: Isolated, perfused, and ventilated rabbit lungs. INTERVENTIONS: Tidal volumes of 8 mL/kg of body weight were used throughout. After stabilization, the lungs were randomized to one of four protocols (lasting 120 mins; n = 6 per group). Group 1 was ventilated at zero end-expiratory pressure. In group 2, PEEP was set above the lower inflection point of the static pressure-volume curve. In group 3, adjustment of PEEP was based on the intratidal compliance-volume curve, as determined by the slice method. In group 4, increasing PEEP levels ensured a plateau airway pressure of 20-25 cm H2O likely to provoke overdistension. MEASUREMENTS AND MAIN RESULTS: The ventilation/perfusion (VA/Q) distribution was analyzed by the multiple inert gas elimination technique. Alveolar derecruitment was indicated by shunt and low VA/Q areas as observed in group 1. In groups 2 and 3, VA/Q data initially indicated full recruitment. In contrast to group 3, shunt increased in group 2 near completion of the experiments. Group 4 showed complete recruitment, but the VA/Q distribution included high VA/Q areas. CONCLUSIONS: The intratidal compliance-volume curve represents a rational basis for adjusting PEEP in the isolated lung model. Because this strategy does not require invasive measures and facilitates continuous assessment of ventilator settings, it may be of clinical interest.

Different strategies to keep the lung open: a study in isolated perfused rabbit lungs.

OBJECTIVE: Atelectatic alveoli can be recruited or kept open either by sustained inflation maneuvers or by positive end-expiratory pressure (PEEP). Little is known about potential interactions between both approaches. Especially, it is not known whether the recruiting effect of sustained inflation maneuvers is maintained in combination with a low PEEP, as suggested recently. In an attempt to answer this question, we combined sustained inflation maneuvers with either high or low PEEP. Both approaches were compared with a strategy likely to result in alveolar atelectasis and with another ensuring adequate alveolar recruitment by adjustment of PEEP alone. DESIGN: Randomized block design. SETTING: Laboratory. SUBJECTS: Isolated perfused rabbit lungs (n = 28). INTERVENTIONS: The lungs were ventilated with a tidal volume of 8 mL/kg. After stabilization, the lungs were randomized to one of four ventilatory strategies, which then were followed for 120 mins: a) PEEP 1 cm H2O (PEEP1, negative control); b) PEEP 1 cm H2O and 30 sec-sustained inflations (20 cm H2O) every 30 mins (SI-1); c) PEEP 3 cm H2O combined with sustained inflations (SI-3); and d) PEEP repeatedly adjusted following a previously established strategy ensuring full alveolar recruitment (DYN, positive control). MEASUREMENTS AND MAIN RESULTS: Distribution of ventilation and perfusion (Va/Q distribution) was analyzed by the multiple inert gas elimination technique. Volume-dependent compliance within the tidal volume was determined by using the slice method. Shunt and Va/Q mismatch significantly differed between SI-1 and SI-3, indicating full alveolar recruitment only in the latter. Data of SI-1 did not differ substantially from those of PEEP1, and data obtained in SI-3 were similar to those of DYN. CONCLUSIONS: First, enduring alveolar recruitment by sustained inflation maneuvers is only possible when the alveoli are stabilized thereafter by sufficient PEEP. Second, a ventilation strategy that uses repeated sustained inflations on a comparably high PEEP may not be superior to adequate adjustment of PEEP alone.