Background: Therapeutic plasma exchange (TPE) is frequently performed in critical care settings for heterogenous indications. However, specific intensive care unit (ICU) data regarding TPE indications, patient characteristics and technical details are sparse. Methods: We performed a retrospective, single-center study using data from January 2010 until August 2021 for patients treated with TPE in an ICU setting at the University Hospital Zurich. Data collected included patient characteristics and outcomes, ICU-specific parameters, as well as apheresis-specific technical parameters and complications. Results: We identified n = 105 patients receiving n = 408 TPEs for n = 24 indications during the study period. The most common was thrombotic microangiopathies (TMA) (38%), transplant-associated complications (16.3%) and vasculitis (14%). One-third of indications (35.2%) could not be classified according to ASFA. Anaphylaxis was the most common TPE-related complication (6.7%), while bleeding complications were rare (1%). The median duration of ICU stay was 8 ± 14 days. Ventilator support, renal replacement therapy or vasopressors were required in 59 (56.2%), 26 (24.8%), and 35 (33.3%) patients, respectively, and 6 (5.7%) patients required extracorporeal membrane oxygenation. The overall hospital survival rate was 88.6%. Conclusion: Our study provides valuable real-world data on heterogenous TPE indications for patients in the ICU setting, potentially supporting decision-making.

Introduction: Calcineurin inhibitors (CNIs), ciclosporin and tacrolimus, are utilized primarily in organ transplantation and the treatment of autoimmune diseases. Since patients depend on these drugs over long periods, they face a potential risk of intoxication. This risk increases substantially when patients are overdosed or inadvertently exposed to cytochrome P450 (CYP) 3A4 inhibitors. Objectives: To analyze the utility of CYP inducers as a plausible treatment modality for acute CNI intoxication using real-world data from the WHO global pharmacovigilance database (VigiBase™) and supporting evidence from published data. Methodology: We explored all individual case safety reports (ICSRs) regarding CNI intoxications registered in VigiBase™. The queries “overdose” or “drug intoxication” were applied against the active ingredients “ciclosporin” and “tacrolimus”. Regarding the utility of CYP inducers, an extensive literature analysis was undertaken. We also report an index clinical case of a 60-year-old liver transplant patient that developed severe tacrolimus intoxication with multiple organ dysfunction at a peak concentration of 33.1 μg/L after a single dose of intravenous fluconazole. Results: Out of 143,710 documented ICSRs reported in VigiBase™ since 1992, 0.26% and 0.02% were registered as CNI overdoses and intoxications, respectively. The main etiological factor for CNI intoxication was the interaction with CYP 3A4 inhibitors (40.0% vs. case reports: 50.0%). The most commonly reported manifestation was acute kidney injury (36.7% vs. case reports: 46.3%). A total of 16.7% of intoxications led to fatal outcomes after drug withdrawal or dose reduction; however, in 43.0% of cases the exact actions undertaken were not reported. In peer-reviewed reports, 34 distinct clinical cases were treated with CYP inducers. Diverse pharmacoenhancement strategies with phenobarbital (5), phenytoin (23) and rifampicin (6) were described with a mean time of achieving the therapeutic target after 2.7 (±0.7), 3.1 (±0.5) and 4.6 (±1.0) days, respectively. In the index case, a therapeutic concentration of 4.9 [4–6 μg/L] was achieved after a 3-day regimen of rifampicin. Conclusion: In addition to general supportive treatment, the administration of phenobarbital, phenytoin, or rifampicin to reverse acute CNI intoxication is a viable treatment modality. The relatively long half-life of phenobarbital coupled with its exclusive renal elimination are potential pitfalls to reckon with. In spite of the favorable pharmacokinetic advantages of rifampicin, phenytoin offers a competitive pharmacodynamic advantage that is indisputable in patients with overt neurotoxicity.

Advances in medical technology and IT infrastructure have led to increased availability of continuous patient data that allows investigation of the longitudinal progression of novel and known diseases in unprecedented detail. However, to accurately describe any underlying pathophysiology with longitudinal data, the individual patient trajectories have to be synchronized based on temporal markers. In this study, we use longitudinal data from 28 critically ill ICU COVID-19 patients to compare the commonly used alignment markers “onset of symptoms”, “hospital admission” and “ICU admission” with a novel objective method based on the peak value of inflammatory marker C-reactive protein (CRP). By applying our CRP-based method to align the progression of neutrophils and lymphocytes, we were able to define a pathophysiological window that allowed further risk stratification in our COVID-19 patient cohort. Our data highlights that proper synchronization of patient data is crucial to differentiate severity subgroups and to allow reliable interpatient comparisons.

Oxygen therapy is a cornerstone in the treatment of critically ill patients. However, excess oxygen administration may promote oxidative cellular injury once hemoglobin is fully saturated and additional oxygen remains dissolved, enhancing reactive oxygen species formation. The combined impact of oxygen administration, pH, and respiratory failure on hyperoxemia across saturation ranges is not well understood. We conducted a retrospective study at a tertiary center to assess how these factors modify hyperoxemia frequency in adult ICU patients. Continuous S_pO₂ measurements were aligned with arterial blood gases (P_aO₂, pH, F_iO₂), and hyperoxemia was evaluated using predefined P_aO₂ thresholds (>120 mmHg and >150 mmHg). Among 21,406 patients with 717,064 paired measurements, prolonged hyperoxemia occurred in over half of mechanically ventilated patients, most commonly in those without or with mild-to-moderate respiratory failure. Acidotic states were associated with higher P_aO₂ values at comparable S_pO₂ levels, consistent with a rightward shift in the oxygen–hemoglobin dissociation curve. S_pO₂ values ≥ 98% were consistently associated with hyperoxemia, whereas 96–97% generally corresponded to P_aO₂ within physiological ranges. Higher F_iO₂ markedly increased hyperoxemia probability, allowing derivation of pH-stratified F_iO₂ exposure limits. Our findings highlight the importance of individualized oxygen therapy, considering pH and respiratory failure phenotype to guide safer oxygen management.