Proton pump inhibitor treatment aggravates bacterial translocation in patients with advanced cirrhosis and portal hypertension.

IMPORTANCE: Long-term prescription of proton pump inhibitors (PPIs) in patients with cirrhosis is common practice. However, in recent years, several observational studies have reported increased complications and negative prognostic effects of PPI treatment in these patients. Judging the significance of these associations is complicated by the fact that a plausible underlying pathomechanism has not been identified so far. In the present study, we address this important issue by investigating the impact of PPI treatment on subclinical bacterial translocation from the gut into the blood stream in patients with advanced cirrhosis and portal hypertension. Indeed, we report significantly aggravated bacterial translocation in cirrhosis patients receiving PPI treatment. This finding is highly relevant, as bacterial translocation is known to promote the development of complications and impair prognosis in patients with cirrhosis. Hence, the present study could establish a plausible link between PPI treatment and adverse effects in cirrhosis.

Decreased Platelet Aggregation in Patients with Decompensated Liver Cirrhosis and TIPS Implantation.

Transjugular intrahepatic portosystemic shunt (TIPS) implantation is an effective treatment of portal hypertension in patients with decompensated liver cirrhosis. However, some patients develop TIPS thrombosis with recurrence of portal hypertension. The role of platelets in TIPS thrombosis and the necessity of antiplatelet therapy is unclear. Therefore, we aimed to study platelet function in patients with liver cirrhosis prior to and after TIPS implantation. Platelet aggregation was tested in peripheral and portal-vein blood patient samples on the day (D) of TIPS implantation (D0), D4 and D30 following the procedure (platelet count above 100 × 103/µL, aspirin starting on D5) using whole-blood impedance aggregometry (WBIA) and light transmission aggregometry (LTA). In addition, surface platelet activation markers (P-selectin, activated GPIIb/IIIa) and platelet-neutrophil complexes (PNCs) were assessed by flow cytometry. Thrombin receptor activating peptide 6 (TRAP-6), adenosine diphosphate (ADP) and arachidonic acid (AA) were used as agonists. Healthy subjects were included as controls. Agonist-induced platelet aggregation was reduced (WBIA: TRAP-6 p < 0.01, ADP p < 0.01, AA p < 0.001; LTA: TRAP-6 p = 0.13, ADP p = 0.05, AA p < 0.01) in patients (D0, n = 13) compared with healthy subjects (n = 9). While surface activation markers at baseline were negligibly low, the percentage of PNCs was higher in patients than in controls (p < 0.05). ADP-induced P-selectin expression was increased (p < 0.001), whereas TRAP-6-induced GPIIb/IIIa activation was impaired (p < 0.001) in patients versus controls. PNC formation in response to agonists was not different between groups. Results did not differ between peripheral and portal-vein blood of patients (D0, n = 11) and did not change over time (D0, D4, D30) following TIPS implantation (n = 9). In summary, patients with decompensated liver cirrhosis display in vitro platelet aggregation defects in response to various agonists. Defective aggregation persists upon TIPS implantation. Therefore, we conclude that antiplatelet treatment to prevent TIPS thrombosis is questionable.

Proton pump inhibitor treatment is associated with acute-on-chronic liver failure in patients with advanced cirrhosis.

BACKGROUND: Acute-on-chronic liver failure (ACLF) is a fatal complication of cirrhosis. Hence, identification of risk factors for ACLF is crucial. Previous studies have linked proton pump inhibitor (PPI) treatment to complications of cirrhosis, however, a possible effect of PPI treatment on the risk of ACLF has not been investigated yet. Therefore, the present study aimed to characterize the impact of PPI treatment on ACLF development. METHODS: A total of 642 patients hospitalized due to complications of cirrhosis were retrospectively identified, and PPI treatment during an observation period of 3 years following the hospitalization was reviewed. Subsequently, 74 patients with newly initiated PPI treatment at the time of hospitalization (PPI group) were 1:1 propensity score matched to 74 patients who received no PPI treatment (no-PPI group). Primary end point was the development of ACLF during the observation period, and secondary endpoints were mortality and upper gastrointestinal bleeding. RESULTS: PPI and no-PPI groups had comparably severe chronic liver disease at baseline. Nevertheless, the cumulative incidence of ACLF in the presence of death as competing risk was markedly higher in the PPI group compared with the no-PPI group. ACLF-related deaths contributed significantly to a higher 3-year mortality in the PPI group. Uni and multivariable competing risk regression models confirmed that PPI treatment was an independent predictor of ACLF in the study collective (subdistribution HR: 1.892, 95% CI: 1.092-3.281, p = 0.023). The impact of PPI treatment on ACLF development was particularly strong in patients with a model for end-stage liver disease score >12. Upper gastrointestinal bleeding was slightly less frequent in the PPI group. CONCLUSIONS: The present results indicate that PPI treatment could be a risk factor for ACLF in patients with advanced cirrhosis.

Enhancement of the haemostatic effect of platelets in the presence of high normal concentrations of von Willebrand factor for critically ill patients needing platelet transfusion-a protocol for the will-plate randomised controlled trial.

INTRODUCTION: von Willebrand Factor (vWF) is a key protein mediating platelet adhesion on the surface of damaged endothelia. To the best of our knowledge, no trial exists that investigated the effect of platelet transfusion in combination with the administration of balanced vWF in severe blood loss, despite being widely used in clinical practice. The Basel Will-Plate study will investigate the impact of the timely administration of balanced vWF (1:1 vWF and FVIII) in addition to platelet transfusion on the need for blood and coagulation factor transfusion in patients admitted to the intensive care unit (ICU) who suffer from severe bleeding. The study hypothesis is based on the assumption that adding balanced vWF to platelets will reduce the overall need for transfusion of blood products compared to the transfusion of platelets alone. METHODS AND ANALYSIS: The Will-Plate study is an investigator-initiated, single-centre, double-blinded randomised controlled clinical trial in 120 critically ill patients needing platelet transfusion. The primary outcome measure will be the number of fresh frozen plasma (FFP) and red blood cell (RBC) transfusions according to groups. Secondary outcome measures include the number of platelet concentrates transfused within the first 48 h after treatment of study medication, quantity of blood loss in the first 48 h after treatment with the study medication, length of stay in ICU and hospital, number of revision surgeries for haemorrhage control, ICU mortality, hospital mortality, 30-day mortality and 1-year mortality. Patients will be followed after 30 days and 1 year for activities of daily living and mortality assessment. The sample size was calculated to detect a 50% reduction in the number of blood products subsequently transfused within 2 days in patients with Wilate® compared to placebo. ETHICS AND DISSEMINATION: This study has been approved by the Ethics Committee of Northwestern and Central Switzerland and will be conducted in compliance with the protocol, the current version of the Declaration of Helsinki, the ICH-GCP or ISO EN 14155 (as far as applicable) and all national legal and regulatory requirements. The study results will be presented at international conferences and published in a peer-reviewed journal. TRIALS REGISTRATION: ClinicalTrials.gov NCT04555785. PROTOCOL VERSION: Clinical Study Protocol Version 2, 01.11.2020. Registered on Sept. 21, 2020.

Aspirin improves transplant-free survival after TIPS implantation in patients with refractory ascites: a retrospective multicentre cohort study.

BACKGROUND AND AIMS: Transjugular intrahepatic portosystemic shunt (TIPS) implantation is an established procedure to treat portal hypertension. Impact of administration of aspirin on transplant-free survival after TIPS remains unknown. METHODS: A multicenter retrospective analysis including patients with TIPS implantation between 2011 and 2018 at three tertiary German Liver Centers was performed. N = 583 patients were included. Survival analysis was performed in a matched cohort after propensity score matching. Patients were grouped according to whether aspirin was (PSM-aspirin-cohort) or was not (PSM-no-aspirin-cohort) administered after TIPS. Primary endpoint of the study was transplant-free survival at 12 months after TIPS. RESULTS: Aspirin improved transplant-free survival 12 months after TIPS with 90.7% transplant-free survival compared to 80.0% (p = 0.001) after PSM. Separated by TIPS indication, aspirin did improve transplant-free survival in patients with refractory ascites significantly (89.6% vs. 70.6% transplant-free survival, p < 0.001), while no significant effect was observed in patients with refractory variceal bleeding (91.1% vs. 92.2% transplant-free survival, p = 0.797). CONCLUSION: This retrospective multicenter study provides first data indicating a beneficial effect of aspirin on transplant-free survival after TIPS implantation in patients with refractory ascites.

A new high protein-to-energy enteral formula with a whey protein hydrolysate to achieve protein targets in critically ill patients: a prospective observational tolerability study.

OBJECTIVES: Current guidelines and expert recommendations stress the need to implement enteral feeds with a higher protein-to-energy ratio to meet protein requirements as recommended while avoiding gastrointestinal side effects and energy overfeeding in ICU patients. MATERIALS AND METHODS: Prospective tolerability study in 18 critically ill patients with a high protein formula (high protein-to-energy (HP:E) formula = Fresubin® Intensive; HPG) compared to a contemporary matched conventional therapy group (CTG). The primary outcome was GI intolerance defined as ≥300 ml daily gastric residual volume (GRV), vomiting, or diarrhea on days 1 and 2. Secondary outcomes were the percentage of patients reaching their protein target on day 4 and overall protein intake. RESULTS: Groups were comparable regarding demographic characteristics, disease severity, organ failures, mechanical ventilation, and NUTRIC score at baseline. Eighteen patients completed the 4-day feeding period. The number of events of GRV of ≥300 ml/day was equal in both groups (33.3%). The incidence of diarrhea and vomiting was low in the HPG (two patients concerned). EN did not need to be discontinued due to intolerance in any group. Seventy-two percent of patients reached protein targets ≥1.3 g/kgBW/d within 4 days after initiation of enteral feeding, which was superior to the CTG (33%). Post-hoc testing showed group differences of protein intake between HPG and CTG were significant at t = 72 h and t = 96 h. Energy targets were met in both groups. CONCLUSION: The HP:E formula containing 33% whey protein hydrolysate is well tolerated in this tolerability study. Due to the HP:E ratio protein targets can be reached faster. Larger randomized trials are needed to confirm preliminary results. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02678325. Registered 2 May 2016.

Validation of color Doppler ultrasound and computed tomography in the radiologic assessment of non-malignant acute splanchnic vein thrombosis.

INTRODUCTION: International guidelines propose color Doppler ultrasound (CDUS) and contrast-enhanced computed tomography (CT) as primary imaging techniques in the diagnosis of acute splanchnic vein thrombosis. However, their reliability in this context is poorly investigated. Therefore, the aim of our study was to validate CDUS and CT in the radiologic assessment of acute splanchnic vein thrombosis, using direct transjugular spleno-portography as gold standard. MATERIALS AND METHODS: 49 patients with non-malignant acute splanchnic vein thrombosis were included in a retrospective, multicenter analysis. The thrombosis' extent in five regions of the splanchnic venous system (right and left intrahepatic portal vein, main trunk of the portal vein, splenic vein, superior mesenteric vein) and the degree of thrombosis (patent, partial thrombosis, complete thrombosis) were assessed by portography, CDUS and CT in a blinded manner. Reliability of CDUS and CT with regard to portography as gold standard was analyzed by calculating Cohen's kappa. RESULTS: Results of CDUS and CT were consistent with portography in 76.6% and 78.4% of examinations, respectively. Cohen's kappa demonstrated that CDUS and CT delivered almost equally reliable results with regard to the portographic gold standard (k = 0.634 [p < 0.001] vs. k = 0.644 [p < 0.001]). In case of findings non-consistent with portography there was no clear trend to over- or underestimation of the degree of thrombosis in both CDUS (60.0% vs. 40.0%) and CT (59.5% vs. 40.5%). CONCLUSIONS: CDUS and CT are equally reliable tools in the radiologic assessment of non-malignant acute splanchnic vein thrombosis.

Prognostic Value of the CLIF-C AD Score in Patients With Implantation of Transjugular Intrahepatic Portosystemic Shunt.

Prognostic assessment of patients with liver cirrhosis allocated for implantation of a transjugular intrahepatic portosystemic shunt (TIPS) is a challenging task in clinical practice. The aim of our study was to assess the prognostic value of the CLIF-C AD (Acute Decompensation) score in patients with TIPS implantation. Transplant-free survival (TFS) and 3-month mortality were reviewed in 880 patients who received de novo TIPS implantation for the treatment of cirrhotic portal hypertension. The prognostic value of the CLIF-C AD score was compared with the Model for End-Stage Liver Disease (MELD) score, Child-Pugh score, and albumin-bilirubin (ALBI) score using Harrell's C concordance index. The median TFS after TIPS implantation was 40.0 (34.6-45.4) months. The CLIF-C AD score (c = 0.635 [0.609-0.661]) was superior in the prediction of TFS in comparison to MELD score (c = 0.597 [0.570-0.623], P = 0.006), Child-Pugh score (c = 0.579 [0.552-0.606], P < 0.001), and ALBI score (c = 0.573 [0.545-0.600], P < 0.001). However, the CLIF-C AD score did not perform significantly better than the MELD-Na score (c = 0.626 [0.599-0.653], P = 0.442). There were no profound differences in the scores' ranking with respect to indication for TIPS implantation, stent type, or underlying liver disease. Subgroup analyses revealed that a CLIF-C AD score >45 was a predictor of 3-month mortality in the supposed low-risk group of patients with a MELD score ≤12 (14.7% vs. 5.1%, P < 0.001). Conclusion: The CLIF-C AD score is suitable for prognostic assessment of patients with cirrhotic portal hypertension receiving TIPS implantation. In the prediction of TFS, the CLIF-C AD score is superior to MELD score, Child-Pugh score, and ALBI score but not the MELD-Na score.

Blood reelin in the progression of chronic liver disease.

PURPOSE: Reelin is an extracellular matrix protein originally found to be associated with neuropsychiatric disorders. Recent findings indicate, that reelin may also play an important role in the process of liver fibrosis as well as in the development of hepatocellular carcinoma (HCC). Against this background, the aim of our study was to explore alterations in blood reelin levels in different stages of chronic liver diseases. PATIENTS AND METHODS: We analyzed blood samples of patients with chronic liver disease without liver fibrosis (n â€‹= â€‹25), with liver fibrosis (n â€‹= â€‹36), with liver cirrhosis (n â€‹= â€‹74), with HCC (n â€‹= â€‹26) as well as of healthy controls (n â€‹= â€‹15). Blood reelin concentrations were determined utilizing an enzyme-linked immunosorbent assay. RESULTS: Blood reelin levels were significantly elevated in patients who had liver fibrosis or cirrhosis compared to patients without liver fibrosis and healthy controls (13.9 (10.2-21.1) ng/ml vs. 11.2 (8.8-16.8) ng/ml, p â€‹= â€‹0.032). Importantly, patients with HCC displayed significantly higher reelin concentrations compared to patients with liver cirrhosis alone (27.0 (17.3-35.9) ng/ml vs. 16.6 (11.0-22.7) ng/ml, p â€‹< â€‹0.001). Blood reelin was not relevantly linked to liver function, inflammation and etiology of liver disease. CONCLUSIONS: Our results demonstrate, that blood reelin levels are altered in different stages of chronic liver disease, which makes reelin a potential biomarker in this setting. This may be especially relevant with regard to its use as an additional tumor marker of HCC.

Refining prediction of survival after TIPS with the novel Freiburg index of post-TIPS survival.

BACKGROUND & AIMS: Transjugular intrahepatic portosystemic shunt (TIPS) implantation is an effective and safe treatment for complications of portal hypertension. Survival prediction is important in these patients as they constitute a high-risk population. Therefore, the aim of our study was to develop an alternative prognostic model for accurate survival prediction after planned TIPS implantation. METHODS: A total of 1,871 patients with de novo TIPS implantation for ascites or secondary prophylaxis of variceal bleeding were recruited retrospectively. The study cohort was divided into a training set (80% of study patients; n = 1,496) and a validation set (20% of study patients; n = 375). Further, patients with early (preemptive) TIPS implantation due to variceal bleeding were included as another validation cohort (n = 290). Medical data and overall survival (OS) were assessed. A Cox regression model was used to create an alternative prediction model, which includes significant prognostic factors. RESULTS: Age, bilirubin, albumin and creatinine were the most important prognostic factors. These parameters were included in a new score named the Freiburg index of post-TIPS survival (FIPS). The FIPS score was able to identify high-risk patients with a significantly reduced median survival of 5.0 (3.1-6.9) months after TIPS implantation in the training set. These results were confirmed in the validation set (median survival of 3.1 [0.9-5.3] months). The FIPS score showed better prognostic discrimination compared to the Child-Pugh, MELD, MELD-Na score and the bilirubin-platelet model. However, the FIPS score showed insufficient prognostic discrimination in patients with early TIPS implantation. CONCLUSIONS: The FIPS score is superior to established scoring systems for the identification of high-risk patients with a worse prognosis following elective TIPS implantation. LAY SUMMARY: Implantation of a transjugular intrahepatic portosystemic shunt (TIPS) is a safe and effective treatment for patients with cirrhosis and clinically significant portal hypertension. However, risk stratification is a major challenge in these patients as currently available scoring systems have major drawbacks. Age, bilirubin, albumin and creatinine were included in a new risk score which was named the Freiburg index of post-TIPS survival (FIPS). The FIPS score can identify patients at high risk and may guide clinical decision making.

Haemophagocytic lymphohistiocytosis and liver failure-induced massive hyperferritinaemia in a male COVID-19 patient.

The authors present the case of a 58-year-old man with the unique combination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and, later on, haemophagocytic lymphohistiocytosis admitted to the intensive care unit. During his ICU stay the patient developed a variety of complications including acute respiratory distress syndrome, pulmonary embolism, right heart failure and suspected HLH leading to multiorgan failure and death. Despite the proven diagnosis of haemophagocytic lymphohistiocytosis, the excessively high ferritin levels of the patient did not seem fully explained by this diagnosis. Therefore, the authors want to highlight different causes of hyperferritinaemia in critically ill patients and underline the importance of differential diagnoses when interpreting continuously rising ferritin levels.

Proton pump inhibitor therapy is associated with reduced survival following first-time transarterial chemoembolization in patients with hepatocellular carcinoma.

BACKGROUND AND AIMS: Several studies have reported associations of proton pump inhibitor (PPI) treatment with the incidence of complications and even increased mortality in patients with liver cirrhosis. Up to now, there are no studies on the impact of PPI treatment in patients with hepatocellular carcinoma (HCC). Therefore, the aim of our study was to investigate the prognostic effects of PPI treatment in a cohort of patients with HCC treated by transarterial chemoembolization (TACE). METHODS: Three hundred fifty-eight patients with HCC that received first-time TACE were included in a retrospective analysis. We explored effects of PPI treatment using uni- and multivariable regression models. RESULTS: One hundred sixty-seven of the 358 patients (46.6%) received PPI treatment. Median transplant-free survival after TACE was significantly lower in patients treated with PPIs compared to patients without PPI treatment [16.0 (10.7-21.3) months vs. 26 (22.2-29.8) months, P = 0.006]. Importantly, PPI treatment remained a significant prognostic factor for reduced survival after adjustment for patient demographics, tumor stadium and liver function [hazard ratio (HR) 1.40, 95% confidence interval (CI) 1.09-1.78, P = 0.005]. We observed a dose-dependent association of PPI treatment with survival: A higher daily PPI dose was an independent prognostic factor for reduced survival (HR 1.32, 95% CI 1.14-1.54, P < 0.001). Notably, 58.1% of patients receiving PPIs had no clear indication therefor. CONCLUSION: PPI treatment is associated with reduced survival in patients with HCC in a dose-dependent manner. Thus, indication for PPI treatment should be evaluated attentively in these patients. Further, prospective studies are needed to validate the findings of this study.

Plasma Cyclic Guanosine Monophosphate Is a Promising Biomarker of Clinically Significant Portal Hypertension in Patients With Liver Cirrhosis.

Introduction: Despite intensive research, reliable blood-derived parameters to detect clinically significant portal hypertension (CSPH) in patients with cirrhosis are lacking. As altered homeostasis of cyclic guanosine monophosphate (cGMP), the central mediator of vasodilatation, is an essential factor in the pathogenesis of portal hypertension, the aim of our study was to evaluate plasma cGMP as potential biomarker of cirrhotic portal hypertension. Methods: Plasma cGMP was analyzed in cirrhotic patients with CSPH (ascites, n = 39; esophageal varices, n = 31), cirrhotic patients without CSPH (n = 21), patients with chronic liver disease without cirrhosis (n = 11) and healthy controls (n = 8). cGMP was evaluated as predictor of CSPH using logistic regression models. Further, the effect of transjugular intrahepatic portosystemic shunt (TIPS) placement on plasma cGMP was investigated in a subgroup of cirrhotic patients (n = 13). Results: Plasma cGMP was significantly elevated in cirrhotic patients with CSPH compared to cirrhotic patients without CSPH [78.1 (67.6-89.2) pmol/ml vs. 39.1 (35.0-45.3) pmol/l, p < 0.001]. Of note, this effect was consistent in the subgroup of patients with esophageal varices detected at screening endoscopy who had no prior manifestations of portal hypertension (p < 0.001). Cirrhotic patients without CSPH displayed no significant elevation of plasma cGMP compared to patients without cirrhosis (p = 0.347) and healthy controls (p = 0.200). Regression analyses confirmed that cGMP was an independent predictor of CSPH (OR 1.042, 95% CI 1.008-1.078, p = 0.016). Interestingly, portal decompression by TIPS implantation did not lead to normalization of plasma cGMP levels (p = 0.101). Conclusions: Plasma cGMP is a promising biomarker of CSPH in patients with cirrhosis, especially with respect to screening for esophageal varices. The lacking normalization of plasma cGMP after portal decompression suggests that elevated plasma cGMP in cirrhotic portal hypertension is mainly a correlate of systemic and splanchnic vasodilatation, as these alterations have been shown to persist after TIPS implantation.

Ketamine vs. haloperidol for prevention of cognitive dysfunction and postoperative delirium: A phase IV multicentre randomised placebo-controlled double-blind clinical trial.

STUDY OBJECTIVE: Delirium is frequently observed in the postoperative and intensive care unit (ICU) population. Due to the multifactorial origin of delirium and according to international guidelines (e.g., American Geriatrics Society; Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption (PADIS) guideline), there are several but no incontestable options for prevention and symptomatic treatment. The purpose of the Baden PRIDe (Prevention and Reduction of Incidence of postoperative Delirium) trial was to determine whether postoperative cognitive dysfunction and delirium could be prevented by the combination of possible preventive agents such as haloperidol and ketamine. In addition, pre- and postoperative levels of the biomarkers cortisol, neuron specific enolase (NSE) and S100ß were measured to investigate their dynamics in delirious and non-delirious patients after surgery. DESIGN: The Baden PRIDe Trial was an investigator-initiated, phase IV, two-centre, randomised, placebo-controlled, double-blind clinical trial. SETTING: Perioperative care. PATIENTS: 182 adult patients that underwent elective or emergency surgery under general or combined (i.e., general and regional) anaesthesia. INTERVENTIONS: Pre-anaesthetic, pharmacologic prevention of postoperative brain dysfunction with haloperidol, ketamine, and the combination of both vs. placebo. MEASUREMENTS: Assessment of cognitive performance pre- and postoperatively with the MMSE, the DOS, the Nursing Delirium Screening Scale (Nu-DESC) or the Intensive Care Delirium Screening Checklist (ICDSC) during ICU stay. MAIN RESULTS: None of the three study arms - haloperidol, ketamine, or both drugs combined - was significantly superior to placebo for prevention of postoperative brain dysfunction and delirium (P = 0.39). Measured levels of postoperative cortisol were significantly higher in delirious patients. S-100ß levels were significantly higher in all postoperative outcome groups (cognitive impairment, delirium, no cognitive decline), whereas postoperative NSE levels declined in all groups. CONCLUSIONS: The study results offer no possibility for a novel recommendation for prevention of postoperative cognitive decline including delirium. Perioperative S-100ß trajectories in patients with cognitive deterioration suggest affection of glial cells in particular. TRIAL REGISTRATION: ClinicalTrials.govNCT02433041; registered on April 7, 2015.

Study protocol for a prospective randomised double-blind placebo-controlled clinical trial investigating a Better Outcome with Melatonin compared to Placebo Administered to normalize sleep-wake cycle and treat hypoactive ICU Delirium: the Basel BOMP-AID study.

INTRODUCTION: Delirium is frequently observed in the intensive care unit (ICU) population, in particular. Until today, there is no evidence for any reliable pharmacological intervention to treat delirium. The Basel BOMP-AID (Better Outcome with Melatonin compared to Placebo Administered to normalize sleep-wake cycle and treat hypoactive ICU Delirium) randomised trial targets improvement of hypoactive delirium therapy in critically ill patients and will be conducted as a counterpart to the Basel ProDex Study (Study Protocol, BMJ Open, July 2017) on hyperactive and mixed delirium. The aim of the BOMP-AID trial is to assess the superiority of melatonin to placebo for the treatment of hypoactive delirium in the ICU. The study hypothesis is based on the assumption that melatonin administered at night restores a normal circadian rhythm, and that restoration of a normal circadian rhythm will cure delirium. METHODS AND ANALYSIS: The Basel BOMP-AID study is an investigator-initiated, single-centre, randomised controlled clinical trial for the treatment of hypoactive delirium with the once daily oral administration of melatonin 4 mg versus placebo in 190 critically ill patients. The primary outcome measure is delirium duration in 8-hour shifts. Secondary outcome measures include delirium-free days and death at 28 days after study inclusion, number of ventilator days, length of ICU and hospital stay, and sleep quality. Patients will be followed after 3 and 12 months for activities of daily living and mortality assessment. Sample size was calculated to demonstrate superiority of melatonin compared with placebo regarding the duration of delirium. Results will be presented using an intention-to-treat approach. ETHICS AND DISSEMINATION: This study has been approved by the Ethics Committee of Northwestern and Central Switzerland and will be conducted in compliance with the protocol, the current version of the Declaration of Helsinki, the International Conference on Harmonisation (ICH) of technical requirements for registration of pharmaceuticals for human use; Good Clinical Practice (GCP) or ISO EN 14155 (as far as applicable), as well as all national legal and regulatory requirements. Study results will be presented in international conferences and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03438526. PROTOCOL VERSION: Clinical Study Protocol Version 3, 10.03.2019.