Hyponatremia is the most common electrolyte disorder in hospitalized patients and is known to be associated with increased mortality. The administration of antegrade single-shot, up to two liters, histidine-tryptophane-ketoglutarate (HTK) solution for adequate electromechanical cardiac arrest and myocardial preservation during minimally invasive aortic valve replacement (MIAVR) is a standard procedure. We aimed to determine the impact of HTK infusion on electrolyte and acid–base balance. In this retrospective analysis we reviewed data on patient characteristics, type of surgery, arterial blood gas analysis during surgery and intra-/postoperative laboratory results of patients receiving surgery for MIAVR at a large tertiary care university hospital. A total of 25 patients were included in the study. All patients were normonatremic at start of surgery. All patients developed hyponatremia after administration of HTK solution with a significant drop of serum sodium of 15 mmol/L (p < 0.01). Measured osmolality did not change during all times of surgery compared to start of surgery (p = 0.28 – p = 0.79), indicating isotonic hyponatremia. After administration of HTK solution pH fell significantly due to development of metabolic acidosis. Acute hyponatremia during cardioplegia with HTK solution is isotonic and should probably not be corrected without presence of hypotonicity as confirmed by measurement of serum osmolality.

Background: Acute lung injury (ALI) occurs in 23% unilateral. Models of unilateral ALI were developed and used previously without clearly demonstrating the strictly unilateral nature and severity of lung injury by the key parameters characterizing ALI as defined by the American Thoracic Society (ATS). Thus, the use of unilateral ALI remained rare despite the innovative approach. Therefore, we developed a unilateral model of ALI and focused on the crucial parameters characterizing ALI. This model can serve for direct comparisons between the injured and intact lungs within single animals, thus, reducing the number of animals required for valid experimental conclusions. Methods: We established the model in nine pigs, followed by an evaluation of key parameters in six pigs (main study). Pigs were ventilated using an adapted left double-lumen tube for lung separation and two ventilators. ALI was induced in the left lung with cyclic rinsing (NaCl 0.9% + Triton® X-100), after which pigs were ventilated for different time spans to test for the timing of ALI onset. Ventilatory and metabolic parameters were evaluated, and bronchoalveolar lavage (BAL) was performed for measurements of inflammatory mediators. Finally, histopathological specimens were collected and examined in respect of characteristics defining the lung injury score (LIS) as suggested by the ATS. Results: After adjustments of the model (n = 9) we were able to induce strictly left unilateral ALI in all six pigs of the evaluation study. The median lung injury score was 0.72 (IQR 0.62–0.79) in the left lung vs 0.14 (IQR 0.14–0.16; p < 0.05) in the right lung, confirming unilateral ALI. A significant and sustained drop in pulmonary compliance (C_dyn) of the left lung occurred immediately, whereas C_dyn of the right lung remained unchanged (p < 0.05). BAL fluid concentrations of interleukin-6 and -8 were increased in both lungs. Conclusions: We established a model of unilateral ALI in pigs, confirmed by histopathology, and typical changes in respiratory mechanics and an inflammatory response. This thoroughly evaluated model could serve as a basis for future studies and for comparing pathophysiological and pharmacological changes in the uninjured and injured lung within the same animal.

Background: An erector spinae plane block (ESPB) has gained popularity due to its effectiveness and simplicity for pain relief. However, it is uncertain whether an ESPB provides superior analgesia after a VATS or thoracotomy compared to other regional and systemic analgesic techniques. Methods: A retrospective cohort study was conducted from January to June 2023 comparing an ESPB with intravenous combination analgesia (IV–CA) in VATS patients and with thoracic epidural analgesia (TEA) in thoracotomy patients. The primary endpoint was the opioid demand during the first two hours in the post-anesthesia care unit (PACU). The secondary outcomes included the pain scores and adverse events. Results: A total of 61.2% of the 165 included VATS patients and 56.9% of the 72 thoracotomy patients were treated with an ESPB. Following a VATS, an ESPB decreased the median piritramide demand (7.5 [3.0 to 12.0] vs. 10.5 [6.5 to 15.5] mg, p < 0.01). However, after a thoracotomy, an ESPB increased the median piritramide demand (12.0 [6.0 to 15.0] vs. 3.0 [0.0 to 9.0] mg, p < 0.01). The pain scores and adverse events were similar between the groups. Conclusions: An ESPB reduces the piritramide demand in VATS patients compared with IV–CA, providing similar pain relief. However, in thoracotomy patients, an ESPB is associated with an increased piritramide demand compared to TEA. An ESPB is an attractive add-on to IV–CA after a VATS, while TEA remains the gold standard after a thoracotomy.

Monitoring for thrombosis and hemolysis is crucial for patients under extracorporeal or mechanical circulatory support, but it can be costly. We investigated correlations between hemolysis index (HI) and plasma-free hemoglobin (PFH) levels on one hand, and between the HI and plasma lactate dehydrogenase (LDH) levels on the other, in critically ill patients with and without extracorporeal or mechanical circulatory support. Additionally, we calculated the cost reductions if monitoring through HI were to replace monitoring through PFH or plasma LDH. In a single-center study, HI was compared with PFH and plasma LDH levels in blood samples taken for routine purposes in critically ill patients with and without extracorporeal or mechanical circulatory support. A cost analysis, restricted to direct costs associated with each measurement, was made for an average 10-bed ICU. This study included 147 patients: 56 patients with extracorporeal or mechanical circulatory support (450 measurements) and 91 patients without extracorporeal or mechanical circulatory support (562 measurements). The HI correlated well with PFH levels (r = 0.96; p < 0.01) and poorly with plasma LDH levels (r = 0.07; p < 0.01) in patients with extracorporeal or mechanical circulatory support. Similarly, HI correlated well with PFH levels (r = 0.97; p < 0.01) and poorly with plasma LDH levels (r = −0.04; p = 0.39) in patients without extracorporeal or mechanical circulatory support. ROC analyses demonstrated a strong performance of HI, with the curve indicating excellent discrimination in the whole cohort (area under the ROC of 0.969) as well as in patients under ECMO or mechanical circulatory support (area under the ROC of 0.988). Although the negative predictive value of HI for predicting PFH levels > 10 mg/dL was high, its positive predictive value was found to be poor at various cutoffs. A simple cost analysis showed substantial cost reduction if HI were to replace PFH or plasma LDH for hemolysis monitoring. In conclusion, in this cohort of critically ill patients with and without extracorporeal or mechanical circulatory support, HI correlated well with PFH levels, but poorly with plasma LDH levels. Given the high correlation and substantial cost reductions, a strategy utilizing HI may be preferable for monitoring for hemolysis compared to monitoring strategies based on PFH or plasma LDH. The PPV of HI, however, is unacceptably low to be used as a diagnostic test.

Austrian out-of-hospital emergency physicians (OOHEP) undergo mandatory biannual emergency physician refresher courses to maintain their licence. The purpose of this study was to compare different reported emergency skills and knowledge, recommended by the European Resuscitation Council (ERC) guidelines, between OOHEP who work regularly at an out-of-hospital emergency service and those who do not currently work as OOHEP but are licenced. We obtained data from 854 participants from 19 refresher courses. Demographics, questions about their practice and multiple-choice questions about ALS-knowledge were answered and analysed. We particularly explored the application of therapeutic hypothermia, intraosseous access, pocket guide use and knowledge about the participants' defibrillator in use. A multivariate logistic regression analysed differences between both groups of OOHEP. Age, gender, years of clinical experience, ERC-ALS provider course attendance and the self-reported number of resuscitations were control variables. Licenced OOHEP who are currently employed in emergency service are significantly more likely to initiate intraosseous access (OR = 4.013, p < 0.01), they initiate mild-therapeutic hypothermia after successful resuscitation (OR = 2.550, p < 0.01) more often, and knowledge about the used defibrillator was higher (OR = 2.292, p < 0.01). No difference was found for the use of pocket guides.OOHEP who have attended an ERC-ALS provider course since 2005 have initiated more mild therapeutic hypothermia after successful resuscitation (OR = 1.670, p <0.05) as well as participants who resuscitated within the last year (OR = 2.324, p < 0.01), while older OOHEP initiated mild therapeutic hypothermia less often, measured per year of age (OR = 0.913, p <0.01). Licenced and employed OOHEP implement ERC guidelines better into clinical practice, but more training on life-saving rescue techniques needs to be done to improve knowledge and to raise these rates of application.