Detectable Serum Severe Acute Respiratory Syndrome Coronavirus 2 Viral Load (RNAemia) Is Closely Correlated With Drastically Elevated Interleukin 6 Level in Critically Ill Patients With Coronavirus Disease 2019

BACKGROUND

Although the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load in respiratory specimens has been widely used to diagnose coronavirus disease 2019 (COVID-19), it is undeniable that serum SARS-CoV-2 nucleic acid (RNAemia) could be detected in a fraction of COVID-19 patients. However, it is not clear whether testing for RNAemia is correlated with the occurrence of cytokine storms or with the specific class of patients.

METHODS

This study enrolled 48 patients with COVID-19 admitted to the General Hospital of Central Theater Command, People's Liberation Army, a designated hospital in Wuhan, China. The patients were divided into 3 groups according to the Diagnosis and Treatment of New Coronavirus Pneumonia (sixth edition) guidelines issued by the National Health Commission of China. Clinical and laboratory data were collected, and the serum viral load and interleukin 6 (IL-6) level were determined.

RESULTS

Analysis of clinical characteristics of 48 cases of COVID-19 showed that RNAemia was diagnosed only in the critically ill group and seemed to reflect the severity of the disease. Furthermore, the level of the inflammatory cytokine IL-6 in critically ill patients increased significantly, almost 10 times that in other patients. More importantly, the extremely high IL-6 level was closely correlated with the detection of RNAemia (R = 0.902).

CONCLUSIONS

Detectable serum SARS-CoV-2 RNA (RNAemia) in patients with COVID-19 was associated with elevated IL-6 concentration and poor prognosis. Because elevated IL-6 may be part of a larger cytokine storm that could worsen outcome, IL-6 could be a potential therapeutic target for critically ill patients with an excessive inflammatory response.

Antibiotic Use in the Intensive Care Unit: Optimization and De-Escalation

Appropriate antimicrobial therapy is essential to ensuring positive patient outcomes. Inappropriate or suboptimal utilization of antibiotics can lead to increased length of stay, multidrug-resistant infections, and mortality. Critically ill intensive care patients, particularly those with severe sepsis and septic shock, are at risk of antibiotic failure and secondary infections associated with incorrect antibiotic use. Through the initiation of active empiric antibiotic therapy based upon local susceptibilities, daily evaluation of signs and symptoms of infection and narrowing of antibiotic therapy when feasible, providers can streamline the treatment of common intensive care unit (ICU) infections. Optimizing antibiotic dosing through prolonged infusions can be beneficial in intensive care populations with altered pharmacokinetics. Antimicrobial stewardship teams can assist ICU providers in managing and implementing these tactics. This review will discuss the current literature on antibiotic use in the ICU applying antimicrobial stewardship strategies. Based upon the most recent evidence, ICUs would benefit from employing empiric guidelines for antibiotic use, collecting appropriate specimens and implementing molecular diagnostics, optimizing the dosing of antibiotics, and reducing the duration of total therapy. These strategies for antibiotic use have the potential to enhance patient care while preventing adverse outcomes.

Current Concepts of ARDS: A Narrative Review

Acute respiratory distress syndrome (ARDS) is characterized by the acute onset of pulmonary edema of non-cardiogenic origin, along with bilateral pulmonary infiltrates and reduction in respiratory system compliance. The hallmark of the syndrome is refractory hypoxemia. Despite its first description dates back in the late 1970s, a new definition has recently been proposed. However, the definition remains based on clinical characteristic. In the present review, the diagnostic workup and the pathophysiology of the syndrome will be presented. Therapeutic approaches to ARDS, including lung protective ventilation, prone positioning, neuromuscular blockade, inhaled vasodilators, corticosteroids and recruitment manoeuvres will be reviewed. We will underline how a holistic framework of respiratory and hemodynamic support should be provided to patients with ARDS, aiming to ensure adequate gas exchange by promoting lung recruitment while minimizing the risk of ventilator-induced lung injury. To do so, lung recruitability should be considered, as well as the avoidance of lung overstress by monitoring transpulmonary pressure or airway driving pressure. In the most severe cases, neuromuscular blockade, prone positioning, and extra-corporeal life support (alone or in combination) should be taken into account.

The use of echocardiography in acute cardiovascular care: recommendations of the European Association of Cardiovascular Imaging and the Acute Cardiovascular Care Association

Echocardiography is one of the most powerful diagnostic and monitoring tools available to the modern emergency/critical care practitioner. Currently, there is a lack of specific European Association of Cardiovascular Imaging/Acute Cardiovascular Care Association recommendations for the use of echocardiography in acute cardiovascular care. In this document, we describe the practical applications of echocardiography in patients with acute cardiac conditions, in particular with acute chest pain, acute heart failure, suspected cardiac tamponade, complications of myocardial infarction, acute valvular heart disease including endocarditis, acute disease of the ascending aorta and post-intervention complications. Specific issues regarding echocardiography in other acute cardiac care scenarios are also described.

The Lactate/Albumin Ratio: A Valuable Tool for Risk Stratification in Septic Patients Admitted to ICU

The lactate/albumin ratio has been reported to be associated with mortality in pediatric patients with sepsis. We aimed to evaluate the lactate/albumin ratio for its prognostic relevance in a larger collective of critically ill (adult) patients admitted to an intensive care unit (ICU). A total of 348 medical patients admitted to a German ICU for sepsis between 2004 and 2009 were included. Follow-up of patients was performed retrospectively between May 2013 and November 2013. The association of the lactate/albumin ratio (cut-off 0.15) and both in-hospital and post-discharge mortality was investigated. An optimal cut-off was calculated by means of Youden’s index. The lactate/albumin ratio was elevated in non-survivors (p < 0.001). Patients with an increased lactate/albumin ratio were of similar age, but clinically in a poorer condition and had more pronounced laboratory signs of multi-organ failure. An increased lactate/albumin ratio was associated with adverse in-hospital mortality. An optimal cut-off of 0.15 was calculated and was associated with adverse long-term outcome even after correction for APACHE2 and SAPS2. We matched 99 patients with a lactate/albumin ratio >0.15 to case-controls with a lactate/albumin ratio <0.15 corrected for APACHE2 scores: The group with a lactate/albumin ratio >0.15 evidenced adverse in-hospital outcome in a paired analysis with a difference of 27% (95%CI 10–43%; p < 0.01). Regarding long-term mortality, again, patients in the group with a lactate/albumin ratio >0.15 showed adverse outcomes (p < 0.001). An increased lactate/albumin ratio was significantly associated with an adverse outcome in critically ill patients admitted to an ICU, even after correction for confounders. The lactate/albumin ratio might constitute an independent, readily available, and important parameter for risk stratification in the critically ill.

Modelled target attainment after meropenem infusion in patients with severe nosocomial pneumonia: the PROMESSE study

OBJECTIVES

The objective of this study was to propose an optimal treatment regimen of meropenem in critically ill patients with severe nosocomial pneumonia.

PATIENTS AND METHODS

Among 55 patients in intensive care treated with 1 g of meropenem every 8 h for severe nosocomial pneumonia, 30 were assigned to intermittent infusion (II; over 0.5 h) and 25 to extended infusion (EI; over 3 h) groups. Based on plasma and epithelial lining fluid (ELF) concentrations determined at steady-state, pharmacokinetic modelling and Monte Carlo simulations were undertaken to assess the probability of attaining drug concentrations above the MIC for 40%-100% of the time between doses (%T > 1-fold and 4-fold MIC), for 1 or 2 g administered by either method.

RESULTS

Penetration ratio, measured by the ELF/plasma ratio of AUCs, was statistically higher in the EI group than in the II group (mean ± SEM: 0.29 ± 0.030 versus 0.20 ± 0.033, P = 0.047). Considering a maximum susceptibility breakpoint of 2 mg/L, all dosages and modes of infusions achieved 40%-100% T > 1-fold MIC in plasma, but none did so in ELF, and only the 2 g dose over EI achieved 40%-100% T > 4-fold MIC in plasma.

CONCLUSIONS

The optimum regimen to treat severe nosocomial pneumonia was 2 g of meropenem infused over 3 h every 8 h. This regimen achieved the highest pharmacodynamic targets both in plasma and in ELF.

Cefiderocol-Based Combination Therapy for "Difficult-to-Treat" Gram-Negative Severe Infections: Real-Life Case Series and Future Perspectives

Cefiderocol is a new cephalosporin displaying against extensively resistant (XDR) Gram-negative bacteria. We report our experience with cefiderocol-based combination therapies as “rescue” treatments in immunocompromised or critically ill patients or in patients with post-surgical infections who had failed previous regimens. A total of 13 patients were treated from 1 September 2020 to 31 March 2021. In total, 5/13 (38%) patients were classified as critically ill, due to severe COVID-19 lung failure; 4/13 (31%) patients had post-surgical infections and 4/13 (31%) had severe infections in immunocompromised subjects due to solid organ transplantation (2/4) or hematological malignancy (2/4). Overall, 10/13 infections were caused by carbapenem-resistant Acinetobacter baumannii, one by KPC-positive ceftazidime/avibactam-resistant Klebsiella pneumonia and two by Pseudomonas aeruginosa XDR. Based on clinical, microbiological and hematobiochemical evaluation, cefiderocol was associated with different companion drugs, particularly with fosfomycin, high-dose tigecycline and/or colistin. Microbiological eradication was achieved in all cases and the 30-day survival rate was 10/13; two patients died due to SARS-CoV-2 lung failure, whereas one death was attributed to subsequent infections. No recurrent infections within 30 days were reported. Finally, we hereby discuss the therapeutic potential of cefiderocol and the possible place in the therapy of this novel drug.

Beta-Lactams Toxicity in the Intensive Care Unit: An Underestimated Collateral Damage?

Beta-lactams are the most commonly prescribed antimicrobials in intensive care unit (ICU) settings and remain one of the safest antimicrobials prescribed. However, the misdiagnosis of beta-lactam-related adverse events may alter ICU patient management and impact clinical outcomes. To describe the clinical manifestations, risk factors and beta-lactam-induced neurological and renal adverse effects in the ICU setting, we performed a comprehensive literature review via an electronic search on PubMed up to April 2021 to provide updated clinical data. Beta-lactam neurotoxicity occurs in 10-15% of ICU patients and may be responsible for a large panel of clinical manifestations, ranging from confusion, encephalopathy and hallucinations to myoclonus, convulsions and non-convulsive status epilepticus. Renal impairment, underlying brain abnormalities and advanced age have been recognized as the main risk factors for neurotoxicity. In ICU patients, trough concentrations above 22 mg/L for cefepime, 64 mg/L for meropenem, 125 mg/L for flucloxacillin and 360 mg/L for piperacillin (used without tazobactam) are associated with neurotoxicity in 50% of patients. Even though renal complications (especially severe complications, such as acute interstitial nephritis, renal damage associated with drug induced hemolytic anemia and renal obstruction by crystallization) remain rare, there is compelling evidence of increased nephrotoxicity using well-known nephrotoxic drugs such as vancomycin combined with beta-lactams. Treatment mainly relies on the discontinuation of the offending drug but in the near future, antimicrobial optimal dosing regimens should be defined, not only based on pharmacokinetics/pharmacodynamic (PK/PD) targets associated with clinical and microbiological efficacy, but also on PK/toxicodynamic targets. The use of dosing software may help to achieve these goals.

Enteral feeding in the critically ill: comparison between the supine and prone positions: a prospective crossover study in mechanically ventilated patients

INTRODUCTION

Prone position is effective in mechanically ventilated patients to improve oxygenation. It is unknown if prone position affects gastric emptying and the ability of continued enteral feeding.

AIM

To determine tolerance of enteral feeding by measuring gastric residual volumes in enterally fed patients during supine and prone positions.

METHODS

Consecutive mechanically ventilated intensive care patients who were turned to prone position were included. All patients were studied for 6 hours in supine position, immediately followed by 6 hours in prone position, or vice versa. The rate of feeding was unchanged during the study period. Gastric residual volume was measured by suctioning the naso-gastric tube after 3 and 6 hours in the same position. Wilcoxon test and regression analysis were used for analysis.

RESULTS

The median volume of administered enteral feeds was 95 ml after 6 hours in supine position and 110 ml after 6 hours in prone position (P = 0.85). In 10 patients, a greater gastric residual volume was found in prone position. In eight others a greater volume was found in supine position. In 18 of 19 patients, gastric residual volumes in both positions were > or = 150 ml in 6 hours or < or = 150 ml in 6 hours. Significantly more sedatives were used in prone position. Regression analysis excluded dopamine dose and the starting position as confounders.

CONCLUSION

Our results suggest that enteral feeding can be continued when a patient is turned from supine to prone position or vice versa. The results indicate that patients with a clinically significant gastric residual volume in one position are likely to have a clinically significant gastric residual volume in the other position.

Cystatin C-Guided Vancomycin Dosing in Critically Ill Patients: A Quality Improvement Project

BACKGROUND

The aim of the study was to determine whether a vancomycin dosing algorithm based on estimated glomerular filtration rate from creatinine and cystatin C levels (eGFR_cr-cys) improves target trough concentration achievement compared to an algorithm based on estimated creatinine clearance (eCL_cr) in critically ill patients.

STUDY DESIGN

This prospective quality improvement project evaluated intensive care unit (ICU) patients started on intravenous vancomycin using one of 2 different strategies. Dosing regimens were selected and implemented after an individualized goal trough range was established (10-15 or 15-20mg/L). Steady-state goal trough achievement was compared between treatment arms with and without adjustment for potential confounders.

SETTING & PARTICIPANTS

3 medical and surgical ICUs at a single tertiary medical center.

QUALITY IMPROVEMENT PLAN

During January 2012 to October 2013, vancomycin was dosed according to eCL_cr using the Cockcroft-Gault formula (control arm). During December 2013 to May 2015, a multidisciplinary quality improvement team implemented a novel vancomycin dosing algorithm according to eGFR_cr-cys using the CKD-EPI equation (intervention arm).

OUTCOME

Steady-state initial goal vancomycin trough concentration achievement.

MEASUREMENTS & RESULTS

More patients in the intervention arm (67 of 135 [50%]) achieved therapeutic trough vancomycin levels than in the control arm (74 of 264 [28%]; OR, 2.53; 95% CI, 1.65-3.90; P<0.001). Improved trough achievement was maintained even after adjustment for age, sex, APACHE (Acute Physiology and Chronic Health Evaluation) III score, fluid balance, baseline CL_cr, surgical admission diagnosis, presence of sepsis, and goal trough concentration range (adjusted OR, 2.79; 95% CI, 1.76-4.44; P<0.001). Clinical outcomes were similar between groups.

LIMITATIONS

Nonrandomized, incomplete algorithm compliance.

CONCLUSIONS

A vancomycin dosing nomogram based on eGFR_cr-cys significantly improved goal trough achievement compared to eCL_cr among ICU patients with stable kidney function. Further studies are warranted to characterize the relationship between use of cystatin C-guided dosing and clinical outcomes.

Characterization of acute kidney injury in critically ill patients with severe coronavirus disease 2019

BACKGROUND

Coronavirus disease 2019 (COVID-19)-associated acute kidney injury (AKI) frequency, severity and characterization in critically ill patients has not been reported.

METHODS

Single-centre cohort performed from 3 March 2020 to 14 April 2020 in four intensive care units in Bordeaux University Hospital, France. All patients with COVID-19 and pulmonary severity criteria were included. AKI was defined using Kidney Disease: Improving Global Outcomes (KDIGO) criteria. A systematic urinary analysis was performed. The incidence, severity, clinical presentation, biological characterization (transient versus persistent AKI; proteinuria, haematuria and glycosuria) and short-term outcomes were evaluated.

RESULTS

Seventy-one patients were included, with basal serum creatinine (SCr) of 69 ± 21 µmol/L. At admission, AKI was present in 8/71 (11%) patients. Median [interquartile range (IQR)] follow-up was 17 (12-23) days. AKI developed in a total of 57/71 (80%) patients, with 35% Stage 1, 35% Stage 2 and 30% Stage 3 AKI; 10/57 (18%) required renal replacement therapy (RRT). Transient AKI was present in only 4/55 (7%) patients and persistent AKI was observed in 51/55 (93%). Patients with persistent AKI developed a median (IQR) urine protein/creatinine of 82 (54-140) (mg/mmol) with an albuminuria/proteinuria ratio of 0.23 ± 20, indicating predominant tubulointerstitial injury. Only two (4%) patients had glycosuria. At Day 7 after onset of AKI, six (11%) patients remained dependent on RRT, nine (16%) had SCr >200 µmol/L and four (7%) had died. Day 7 and Day 14 renal recovery occurred in 28% and 52%, respectively.

CONCLUSION

Severe COVID-19-associated AKI is frequent, persistent, severe and characterized by an almost exclusive tubulointerstitial injury without glycosuria.

The Adrenal Cortex, an Underestimated Site of SARS-CoV-2 Infection

BACKGROUND

The majority of the critically ill patients may have critical illness-related corticosteroid insufficiency (CIRCI). The therapeutic effect of dexamethasone may be related to its ability to improve cortical function. Recent study showed that dexamethasone can reduce COVID-19 deaths by up to one third in critically ill patients. The aim of this article is to investigate whether SARS-CoV-2 can attack the adrenal cortex to aggravate the relative adrenal insufficiency.

METHODS

We summarized the clinical features of COVID-19 reported in currently available observational studies. ACE2 and TMPRSS2 expression was examined in human adrenal glands by immunohistochemical staining. We retrospectively analyzed serum cortisol levels in critically ill patients with or without COVID-19.

RESULTS

High percentage of critically ill patients with SARS-COV-2 infection in the study were treated with vasopressors. ACE2 receptor and TMPRSS2 serine protease were colocalized in adrenocortical cells in zona fasciculata and zona reticularis. We collected plasma cortisol concentrations in nine critically ill patients with COVID-19. The cortisol levels of critically ill patients with COVID-19 were lower than those in non-COVID-19 critically ill group. Six of the nine COVID-19 critically ill patients had random plasma cortisol concentrations below 10 µg/dl, which met the criteria for the diagnosis of CIRCI.

CONCLUSION

We demonstrate that ACE2 and TMPRSS2 are colocalized in adrenocortical cells, and that the cortisol levels are lower in critically ill patients with COVID-19 as compared to those of non-COVID-19 critically ill patients. Based on our findings, we recommend measuring plasma cortisol level to guide hormonal therapy.

Activity in the chronically critically ill

Although therapeutic activity prevents functional decline and reduces mortality, little is known about typical levels of activity among intensive care unit (ICU) patients. This report of a preliminary study describes typical therapeutic activity and compares the use of two measures of activity in a small sample of chronically critically ill adults. Type, frequency, and duration of therapeutic activity were measured simultaneously with direct observation and actigraphy. The only consistent activity documented was turning (frequency: 3 turns/8 hours; duration: mean average of 11 minutes). Analysis demonstrated acceptable agreement between the two measures of activity for both frequency and duration of therapeutic but not for type of activity. Congruence between measures for duration of activity was also supported. This study provides information for investigators and practitioners who are interested in measuring or implementing therapeutic activity in selected critically ill adults.

Transportation of Critically Ill Patients on Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) may be a life-saving procedure for patients with severe reversible pulmonary or cardiac failure or for patients in need for a bridge to transplantation. ECMO is provided by specialized centers, but patients in need of ECMO are frequently taken care of at other centers. Conventional transports to an ECMO center can be hazardous and deaths have been described. For this reason, many ECMO centers have developed transport programs with mobile ECMO. After request, the mobile team including all necessary equipment to initiate ECMO is sent to the referring hospital, where the patient is cannulated and ECMO commenced. The patient is then transported on ECMO to the ECMO facility by road, helicopter, or fixed-wing aircraft depending on distance, weather conditions, etc. Eight publications have reported series of more than 50 transports on ECMO of which the largest included over 700. Together, these papers report on more than 1400 patient transports on ECMO. Two deaths during transport have occurred. A number of other adverse events are described, but without effect on patient outcome. Survival of patients transported on ECMO is equivalent to that of non-transported ECMO patients. It is concluded that long-, short-distance interhospital transports on ECMO can be performed safely. The staff should be experienced and highly competent in intensive care, ECMO cannulation, ECMO treatment, intensive care transport, and air transport medicine.

Effect of high-dose vitamin D3 on 28-day mortality in adult critically ill patients with severe vitamin D deficiency: a study protocol of a multicentre, placebo-controlled double-blind phase III RCT (the VITDALIZE study)

INTRODUCTION

Observational studies have demonstrated an association between vitamin D deficiency and increased risk of morbidity and mortality in critically ill patients. Cohort studies and pilot trials have suggested promising beneficial effects of vitamin D replacement in the critical ill, at least in patients with severe vitamin D deficiency. As vitamin D is a simple, low-cost and safe intervention, it has potential to improve survival in critically ill patients.

METHODS AND ANALYSIS

In this randomised, placebo-controlled, double-blind, multicentre, international trial, 2400 adult patients with severe vitamin D deficiency (25-hydroxyvitamin D≤12 ng/mL) will be randomised in a 1:1 ratio by www.randomizer.at to receive a loading dose of 540 000 IU cholecalciferol within 72 hours after intensive care unit (ICU) admission, followed by 4000 IU daily for 90 days or placebo. Hypercalcaemia may occur as a side effect, but is monitored by regular checks of the calcium level. The primary outcome is all-cause mortality at 28 days after randomisation. Secondary outcomes are: ICU, hospital, 90-day and 1-year mortality; hospital and ICU length of stay, change in organ dysfunction on day 5 as measured by Sequential Organ Function Assessment (SOFA) score, number of organ failures; hospital and ICU readmission until day 90; discharge destination, self-reported infections requiring antibiotics until day 90 and health-related quality of life. Recruitment status is ongoing.

ETHICS AND DISSEMINATION

National ethical approval was obtained by the Ethics Committee of the University of Graz for Austria, Erasme University Brussels (Belgium) and University Hospital Frankfurt (Germany), and will further be gained according to individual national processes. On completion, results will be published in a peer-reviewed scientific journal. The study findings will be presented at national and international meetings with abstracts online.

TRIAL REGISTRATION

NCT03188796, EudraCT-No: 2016-002460-13.

Risk factors for infection and predictors of mortality among patients with KPC-producing Klebsiella pneumoniae bloodstream infections in the intensive care unit

BACKGROUND

Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-Kp) infections in intensive care units (ICUs) are associated with increased mortality. We aimed to determine risk factors for infection and predictors of 30-day mortality in ICU patients with KPC-Kp bloodstream infections (BSI).

METHODS

During a 26-month period, patients (n = 273) who stayed more than 6 days in the ICU of the University Hospital of Patras, Greece, were divided into 2 groups, those who developed KPC-Kp BSI and those who did not. K. pneumoniae was identified by Vitek 2 technology. Antibiotic susceptibility testing was performed by agar disk diffusion method. Minimum inhibitory concentrations were determined by Etest. The presence of the blaKPC gene was confirmed by PCR. Molecular typing was performed by pulsed-field gel electrophoresis of XbaI-restricted genomic DNA. Epidemiological data were collected by patient chart review.

RESULTS

Five patients had bacteraemia upon admission, while in 48 (17.6%) the BSI developed after 6 days of hospitalization. Risk factors for KPC-Kp BSI in the latter group were the administration of aminoglycosides, number of invasive catheters inserted after the third day, and tracheostomy. The 30-day mortality was 43.4% (23/53 patients). Multivariate analysis revealed that age, SAPS II score at onset of BSI, resistance to colistin, gentamicin, or tigecycline, and septic shock were independently associated with mortality. Treatment with at least 2 appropriate antibiotics was identified as a predictor of a good prognosis.

CONCLUSIONS

Many risk factors are involved in KPC-Kp BSI among ICU patients. The high mortality in patients with KPC-KP BSI in the ICU requires the implementation of appropriate infection control measures.

A Comparison of Colistin versus Colistin Plus Meropenem for the Treatment of Carbapenem-Resistant Acinetobacter baumannii in Critically Ill Patients: A Propensity Score-Matched Analysis

Carbapenem-resistant Acinetobacter baumannii (CRAB), an important nosocomial pathogen, occurs particularly in the intensive care unit (ICU). Thus, the aim of this study was to compare the efficacy and safety of documented treatment with colistin monotherapy versus colistin plus meropenem in critically ill patients with CRAB infections at Chiang Mai University Hospital (CMUH). We conducted a retrospective cohort study of critically ill patients with CRAB infections in an ICU from 2015 to 2017, who received colistin monotherapy versus colistin plus meropenem. After propensity score matching, an adjusted odds ratio (aOR) of a 30-day mortality rate in patients who received colistin plus meropenem was 0.43 compared to those who received colistin monotherapy (95% CI, 0.23–0.82, p = 0.01). aORs of clinical response and microbiological response were also higher in patients who received colistin plus meropenem (1.81, 95% CI 1.01–3.26, p = 0.048 and 2.08, 95% CI 1.11–3.91, p = 0.023, respectively). There was no significant difference in nephrotoxicity (aOR, 0.76, 95% CI, 0.43–1.36, p = 0.363) between colistin monotherapy and colistin plus meropenem. In conclusion, the addition of meropenem to colistin caused a reduction in 30-day mortality, higher clinical and microbiological responses, and did not increase nephrotoxicity compared to colistin monotherapy. Furthermore, 30-day mortality was significantly related with age, receiving vasopressor, having malignancy, and the APACHE II score.

Incidence and risk factors for delirium development in ICU patients - a prospective observational study

BACKGROUND AND AIMS

Delirium is an acute brain dysfunction and a frequent complication in critically ill patients. When present it significantly worsens the prognosis of patients. The aim of this study was to evaluate the incidence of delirium and risk factors for delirium in a mixed group of trauma, medical and surgical ICU patients.

METHODS

A prospective observational study was conducted in one of the six-bed Intensive Care Units of the University Hospital Ostrava in the Czech Republic during a 12-month period. We evaluated the incidence of delirium and its predisposing and precipitating risk factors. All patients were assessed daily using the Confusion Assessment Method for the ICU (CAM-ICU).

RESULTS AND CONCLUSIONS

Of the total of 332 patients with a median APACHE II (the Acute Physiology and Chronic Health Evaluation) score of 12, who were evaluated for delirium, 48 could not be assessed using CAM-ICU (47 due to prolonged coma, 1 due to language barriers). The incidence of delirium was 26.1%, with trauma and medical patients being more likely to develop delirium than surgical patients. Risk of delirium was significantly associated with age ≥ 65 years, and alcohol abuse in their anamnesis, with APACHE II score on admission, and with the use of sedatives and/or vasopressors. Delirious patients who remained in the ICU for a prolonged period showed a greater need for ventilator support and had a greater ICU-mortality.

Sleep quality and circadian rhythm disruption in the intensive care unit: a review

Sleep and circadian rhythm are reported to be severely abnormal in critically ill patients. Disturbed sleep can lead to the development of delirium and, as a result, can be associated with prolonged stay in the intensive care unit (ICU) and increased mortality. The standard criterion method of sleep assessment, polysomnography (PSG), is complicated in critically ill patients due to the practical challenges and interpretation difficulties. Several PSG sleep studies in the ICU reported the absence of normal sleep characteristics in many critically ill patients, making the standard method of sleep scoring insufficient in this patient group. Watson et al proposed a modified classification for sleep scoring in critically ill patients. This classification has not yet been validated. Sleep disturbance in the ICU is a multifactorial problem. The ICU environment, mechanical ventilation, medication, as well as the critical illness itself have been reported as important sleep disturbing factors. Secretion of sleep hormone, melatonin, expressing circadian rhythmicity was found abolished or phase delayed in critically ill patients. Various interventions have been tested in several studies aiming to improve sleep quality and circadian rhythm in the ICU. The results of these studies were inconclusive due to using the sleep assessment methods other than PSG or the absence of a reliable sleep scoring tool for the analysis of the PSG findings in this patient population. Development of a valid sleep scoring classification is essential for further sleep research in critically ill patients.

Assessment of a PK/PD Target of Continuous Infusion Beta-Lactams Useful for Preventing Microbiological Failure and/or Resistance Development in Critically Ill Patients Affected by Documented Gram-Negative Infections

BACKGROUND

Emerging data suggest that more aggressive beta-lactam PK/PD targets could minimize the occurrence of microbiological failure and/or resistance development. This study aims to assess whether a PK/PD target threshold of continuous infusion (CI) beta-lactams may be useful in preventing microbiological failure and/or resistance development in critically ill patients affected by documented Gram-negative infections.

METHODS

Patients admitted to intensive care units from December 2020 to July 2021 receiving continuous infusion beta-lactams for documented Gram-negative infections and having at least one therapeutic drug monitoring in the first 72 h of treatment were included. A receiver operating characteristic (ROC) curve analysis was performed using the ratio between steady-state concentration and minimum inhibitory concentration (C_ss/MIC) ratio as the test variable and occurrence of microbiological failure as the state variable. Area under the curve (AUC) and 95% confidence interval (CI) were calculated. Independent risk factors for the occurrence of microbiological failure were investigated using logistic regression.

RESULTS

Overall, 116 patients were included. Microbiological failure occurred in 26 cases (22.4%). A C_ss/MIC ratio ≤ 5 was identified as PK/PD target cut-off with sensitivity of 80.8% (CI 60.6-93.4%) and specificity of 90.5% (CI 74.2-94.4%), and with an AUC of 0.868 (95%CI 0.793-0.924; p < 0.001). At multivariate regression, independent predictors of microbiological failure were C_ss/MIC ratio ≤ 5 (odds ratio [OR] 34.54; 95%CI 7.45-160.11; p < 0.001) and Pseudomonas aeruginosa infection (OR 4.79; 95%CI 1.11-20.79; p = 0.036).

CONCLUSIONS

Early targeting of CI beta-lactams at C_ss/MIC ratio > 5 during the treatment of documented Gram-negative infections may be helpful in preventing microbiological failure and/or resistance development in critically ill patients.

Invasive aspergillosis in critically ill patients: Review of definitions and diagnostic approaches

Invasive aspergillosis (IA) is an increasingly recognised phenomenon in critically ill patients in the intensive care unit, including in patients with severe influenza and severe coronavirus disease 2019 (COVID-19) infection. To date, there are no consensus criteria on how to define IA in the ICU population, although several criteria are used, including the AspICU criteria and new consensus criteria to categorise COVID-19-associated pulmonary aspergillosis (CAPA). In this review, we describe the epidemiology of IA in critically ill patients, most common definitions used to define IA in this population, and most common clinical specimens obtained for establishing a mycological diagnosis of IA in the critically ill. We also review the most common diagnostic tests used to diagnose IA in this population, and lastly discuss the most common clinical presentation and imaging findings of IA in the critically ill and discuss areas of further needed investigation.

Bench-to-bedside review: severe lactic acidosis in HIV patients treated with nucleoside analogue reverse transcriptase inhibitors

Nucleoside reverse transcriptase inhibitors (NRTIs) are effective antiretroviral therapy for the treatment of HIV-infected patients. NRTIs can induce mitochondrial impairment that leads to a number of adverse events, including symptomatic lactic acidosis. In the present review, we describe the underlying mechanism of NRTI-induced toxicity and the main clinical features of this infrequent, but severe, emerging complication. We also summarise experimental data and clinical observations that support the use of L-carnitine supplementation to reverse NRTI-induced mitochondrial impairment.

Population Pharmacokinetics of Tigecycline in Critically Ill Patients with Severe Infections

We sought to describe the population pharmacokinetics of tigecycline in critically ill patients and to determine optimized dosing regimens of tigecycline for different bacterial infections. This prospective study included 10 critically ill patients given a standard dose of tigecycline. Blood samples were collected during one dosing interval and were analyzed using validated chromatography. Population pharmacokinetics and Monte Carlo dosing simulations were undertaken using Pmetrics. Three target exposures, expressed as ratios of the 24-h area under the curve to MICs (AUC_0-24/MIC), were evaluated (≥17.9 for skin infections, ≥6.96 for intra-abdominal infections, ≥4.5 for hospital-acquired pneumonia). The median age, total body weight, and body mass index (BMI) were 67 years, 69.1 kg, and 24.7 kg/m², respectively. A two-compartment linear model best described the time course of tigecycline concentrations. The parameter estimates (expressed as means ± standard deviations [SD]) from the final model were as follows: clearance (CL), 7.50 ± 1.11 liters/h; volume in the central compartment, 72.50 ± 21.18 liters; rate constant for tigecycline distribution from the central to the peripheral compartment, 0.31 ± 0.16 h^-1; and rate constant for tigecycline distribution from the peripheral to the central compartment, 0.29 ± 0.30 h^-1 A larger BMI was associated with increased CL of tigecycline. Licensed doses were found to be sufficient for Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, and methicillin-resistant Staphylococcus aureus for an AUC_0-24/MIC target of 4.5 or 6.96. For a therapeutic target of 17.9, an increased tigecycline dose is required, especially for patients with higher BMI. The dosing requirements of tigecycline differ with the indication, with pathogen susceptibility, and potentially with patient BMI.

Clinical Efficacy and Nephrotoxicity of the Loading Dose Colistin for the Treatment of Carbapenem-Resistant Acinetobacter baumannii in Critically Ill Patients

Carbapenem-resistant Acinetobacter baumannii (CRAB) is one of the most common causes of nosocomial infections in critically ill patients. Colistin methanesulfonate (CMS), an inactive prodrug, has been considered as a last-resort treatment for CRAB infection in critically ill patients. The objective of this study was to assess 30-day survival and nephrotoxicity in critically ill patients who received non-loading dose (LD) versus LD of CMS for CRAB infection treatment. Between 2012 and 2017, this retrospective cohort analysis was performed at Chiang Mai University Hospital (CMUH), focusing on critically ill patients with CRAB infection who received either non-LD or LD of CMS. A total of 383 patients met the criteria for inclusion. At the 30th day of treatment, the survival rate of patients in the LD CMS group was 1.70 times (adjusted HR) of those in the non-LD group (95% CI = 1.17-2.50, p = 0.006). Clinical response was significantly higher in the LD CMS group than non-LD CMS group (aHR, 1.35, 95% CI, 1.01-1.82, p = 0.046). In addition, a microbiological response-eradication of pre-treatment isolated pathogens in post-treatment cultures-in patients with LD CMS was 1.57 times that of patients with non-LD CMS (95% CI, 1.15-2.15, p = 0.004). Additionally, there was a significant difference in nephrotoxicity between LD CMS and non-LD CMS (aHR, 1.57, 95% CI, 1.14-2.17, p = 0.006). Based on these results, LD CMS should be used to increase the opportunity of patients to achieve favourable outcomes. However, LD CMS was found associated with an increase in nephrotoxicity, so renal function should be closely monitored when LD colistin was administered.

Plasma albumin levels predict risk for nonsurvivors in critically ill patients with COVID-19

Aim: We aimed to explore the biomarkers for disease progression or the risk of nonsurvivors. Materials & methods: This study included 134 hospitalized patients with confirmed COVID-19 infection. The outcome of moderate versus severe versus critically ill patients and survivors versus nonsurvivors were compared. Results: An increase in the severity of COVID-19 pneumonia was positively associated with lower levels of platelets and albumin (all p < 0.05). In the critical group, the plasma levels of albumin continued to have a significant association for the risk of nonsurvivors (p < 0.05), even after adjusting for confounding factors. Conclusion: Albumin levels could be used as an independent predictor of the risk of nonsurvivors in critically ill patients with COVID-19.