Liberation from mechanical ventilation in critically ill patients: Korean Society of Critical Care Medicine Clinical Practice Guidelines.

BACKGROUND: Successful liberation from mechanical ventilation is one of the most crucial processes in critical care because it is the first step by which a respiratory failure patient begins to transition out of the intensive care unit and return to their own life. Therefore, when devising appropriate strategies for removing mechanical ventilation, it is essential to consider not only the individual experiences of healthcare professionals, but also scientific and systematic approaches. Recently, numerous studies have investigated methods and tools for identifying when mechanically ventilated patients are ready to breathe on their own. The Korean Society of Critical Care Medicine therefore provides these recommendations to clinicians about liberation from the ventilator. METHODS: Meta-analyses and comprehensive syntheses were used to thoroughly review, compile, and summarize the complete body of relevant evidence. All studies were meticulously assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) method, and the outcomes were presented succinctly as evidence profiles. Those evidence syntheses were discussed by a multidisciplinary committee of experts in mechanical ventilation, who then developed and approved recommendations. RESULTS: Recommendations for nine PICO (population, intervention, comparator, and outcome) questions about ventilator liberation are presented in this document. This guideline includes seven conditional recommendations, one expert consensus recommendation, and one conditional deferred recommendation. CONCLUSIONS: We developed these clinical guidelines for mechanical ventilation liberation to provide meaningful recommendations. These guidelines reflect the best treatment for patients seeking liberation from mechanical ventilation.

Shock indices are associated with in-hospital mortality among patients with septic shock and normal left ventricular ejection fraction.

BACKGROUND: The understanding of shock indices in patients with septic shock is limited, and their values may vary depending on cardiac function. METHODS: This prospective cohort study was conducted across 20 university-affiliated hospitals (21 intensive care units [ICUs]). Adult patients (≥19 years) with septic shock admitted to the ICUs during a 29-month period were included. The shock index (SI), diastolic shock index (DSI), modified shock index (MSI), and age shock index (Age-SI) were calculated at sepsis recognition (time zero) and ICU admission. Left ventricular (LV) function was categorized as either normal LV ejection fraction (LVEF ≥ 50%) or decreased LVEF (<50%). RESULTS: Among the 1,194 patients with septic shock, 392 (32.8%) who underwent echocardiography within 24 h of time zero were included in the final analysis (normal LVEF: n = 246; decreased LVEF: n = 146). In patients with normal LVEF, only survivors demonstrated significant improvement in SI, DSI, MSI, and Age-SI values from time zero to ICU admission; however, no notable improvements were found in all patients with decreased LVEF. The completion of vasopressor or fluid bundle components was significantly associated with improved indices in patients with normal LVEF, but not in those with decreased LVEF. In multivariable analysis, each of the four indices at ICU admission was significantly associated with in-hospital mortality (P < 0.05) among patients with normal LVEF; however, discrimination power was better in the indices for patients with lower lactate levels (≤ 4.0 mmol/L), compared to those with higher lactate levels. CONCLUSIONS: The SI, DSI, MSI, and Age-SI at ICU admission were significantly associated with in-hospital mortality in patients with septic shock and normal LVEF, which was not found in those with decreased LVEF. Our study emphasizes the importance of interpreting shock indices in the context of LV function in septic shock.

Association between mechanical power and intensive care unit mortality in Korean patients under pressure-controlled ventilation.

BACKGROUND: Mechanical power (MP) has been reported to be associated with clinical outcomes. Because the original MP equation is derived from paralyzed patients under volume-controlled ventilation, its application in practice could be limited in patients receiving pressure-controlled ventilation (PCV). Recently, a simplified equation for patients under PCV was developed. We investigated the association between MP and intensive care unit (ICU) mortality. METHODS: We conducted a retrospective analysis of Korean data from the Fourth International Study of Mechanical Ventilation. We extracted data of patients under PCV on day 1 and calculated MP using the following simplified equation: MPPCV = 0.098 ∙ respiratory rate ∙ tidal volume ∙ (ΔPinsp + positive end-expiratory pressure), where ΔPinsp is the change in airway pressure during inspiration. Patients were divided into survivors and non-survivors and then compared. Multivariable logistic regression was performed to determine association between MPPCV and ICU mortality. The interaction of MPPCV and use of neuromuscular blocking agent (NMBA) was also analyzed. RESULTS: A total of 125 patients was eligible for final analysis, of whom 38 died in the ICU. MPPCV was higher in non-survivors (17.6 vs. 26.3 J/min, P<0.001). In logistic regression analysis, only MPPCV was significantly associated with ICU mortality (odds ratio, 1.090; 95% confidence interval, 1.029-1.155; P=0.003). There was no significant effect of the interaction between MPPCV and use of NMBA on ICU mortality (P=0.579). CONCLUSIONS: MPPCV is associated with ICU mortality in patients mechanically ventilated with PCV mode, regardless of NMBA use.

Ambulatory Status at Discharge Predicts Six-Month Mortality in Patients with COVID-19: A Retrospective Cohort Study.

This retrospective cohort study aimed to evaluate the association between ambulatory status at discharge and six-month post-discharge mortality among adults with coronavirus disease (COVID-19). We analyzed data from 398 patients aged over 18 admitted to a tertiary hospital in South Korea between December 2019 and June 2022. Patients were classified into two groups based on their ambulatory status at discharge: ambulatory (able to walk independently, n = 286) and non-ambulatory (unable to walk independently, requiring wheelchair or bed-bound, n = 112). Our analysis revealed that six-month survival rates were significantly higher in the ambulatory group (94.2%) compared to the non-ambulatory group (84.4%). Multivariate analysis identified ambulatory status at discharge (p = 0.047) and pre-existing malignancy (p = 0.007) as significant prognostic factors for post-discharge survival. This study highlights that the ability to walk independently at discharge is a crucial predictor of six-month survival in COVID-19 patients. These findings emphasize the need for interventions to improve the physical performance of non-ambulatory patients, potentially enhancing their survival prospects. This underscores the importance of targeted rehabilitation and physical therapy for the comprehensive care of COVID-19 survivors.

Comparison of noninvasive cardiac output and stroke volume measurements using electrical impedance tomography with invasive methods in a swine model.

Pulmonary artery catheterization (PAC) has been used as a clinical standard for cardiac output (CO) measurements on humans. On animals, however, an ultrasonic flow sensor (UFS) placed around the ascending aorta or pulmonary artery can measure CO and stroke volume (SV) more accurately. The objective of this paper is to compare CO and SV measurements using a noninvasive electrical impedance tomography (EIT) device and three invasive devices using UFS, PAC-CCO (continuous CO) and arterial pressure-based CO (APCO). Thirty-two pigs were anesthetized and mechanically ventilated. A UFS was placed around the pulmonary artery through thoracotomy in 11 of them, while the EIT, PAC-CCO and APCO devices were used on all of them. Afterload and contractility were changed pharmacologically, while preload was changed through bleeding and injection of fluid or blood. Twenty-three pigs completed the experiment. Among 23, the UFS was used on 7 pigs around the pulmonary artery. The percentage error (PE) between COUFS and COEIT was 26.1%, and the 10-min concordance was 92.5%. Between SVUFS and SVEIT, the PE was 24.8%, and the 10-min concordance was 94.2%. On analyzing the data from all 23 pigs, the PE between time-delay-adjusted COPAC-CCO and COEIT was 34.6%, and the 10-min concordance was 81.1%. Our results suggest that the performance of the EIT device in measuring dynamic changes of CO and SV on mechanically-ventilated pigs under different cardiac preload, afterload and contractility conditions is at least comparable to that of the PAC-CCO device. Clinical studies are needed to evaluate the utility of the EIT device as a noninvasive hemodynamic monitoring tool.

Clinical effects of bacteremia in sepsis patients with community-acquired pneumonia.

BACKGROUND: Data regarding the clinical effects of bacteremia on severe community-acquired pneumonia (CAP) are limited. Thus, we investigated clinical characteristics and outcomes of severe CAP patients with bacteremia compared with those of subjects without bacteremia. In addition, we evaluated clinical factors associated with bacteremia at the time of sepsis awareness. METHODS: We enrolled sepsis patients diagnosed with CAP at emergency departments (EDs) from an ongoing nationwide multicenter observational registry, the Korean Sepsis Alliance, between September 2019 and December 2020. For evaluation of clinical factors associated with bacteremia, we divided eligible patients into bacteremia and non-bacteremia groups, and logistic regression analysis was performed using the clinical characteristics at the time of sepsis awareness. RESULT: During the study period, 1,510 (47.9%) sepsis patients were caused by CAP, and bacteremia was identified in 212 (14.0%) patients. Septic shock occurred more frequently in the bacteremia group than in the non-bacteremia group (27.4% vs. 14.8%; p < 0.001). In multivariable analysis, hematologic malignancies and septic shock were associated with an increased risk of bacteremia. However, chronic lung disease was associated with a decreased risk of bacteremia. Hospital mortality was significantly higher in the bacteremia group than in the non-bacteremia group (27.3% vs. 40.6%, p < 0.001). The most prevalent pathogen in blood culture was Klebsiella pneumoniae followed by Escherichia coli in gram-negative pathogens. CONCLUSION: The incidence of bacteremia in severe CAP was low at 14.0%, but the occurrence of bacteremia was associated with increased hospital mortality. In severe CAP, hematologic malignancies and septic shock were associated with an increased risk of bacteremia.

Deep Learning-Based Early Warning Score for Predicting Clinical Deterioration in General Ward Cancer Patients.

BACKGROUND: Cancer patients who are admitted to hospitals are at high risk of short-term deterioration due to treatment-related or cancer-specific complications. A rapid response system (RRS) is initiated when patients who are deteriorating or at risk of deteriorating are identified. This study was conducted to develop a deep learning-based early warning score (EWS) for cancer patients (Can-EWS) using delta values in vital signs. METHODS: A retrospective cohort study was conducted on all oncology patients who were admitted to the general ward between 2016 and 2020. The data were divided into a training set (January 2016-December 2019) and a held-out test set (January 2020-December 2020). The primary outcome was clinical deterioration, defined as the composite of in-hospital cardiac arrest (IHCA) and unexpected intensive care unit (ICU) transfer. RESULTS: During the study period, 19,739 cancer patients were admitted to the general wards and eligible for this study. Clinical deterioration occurred in 894 cases. IHCA and unexpected ICU transfer prevalence was 1.77 per 1000 admissions and 43.45 per 1000 admissions, respectively. We developed two models: Can-EWS V1, which used input vectors of the original five input variables, and Can-EWS V2, which used input vectors of 10 variables (including an additional five delta variables). The cross-validation performance of the clinical deterioration for Can-EWS V2 (AUROC, 0.946; 95% confidence interval [CI], 0.943-0.948) was higher than that for MEWS of 5 (AUROC, 0.589; 95% CI, 0.587-0.560; p < 0.001) and Can-EWS V1 (AUROC, 0.927; 95% CI, 0.924-0.931). As a virtual prognostic study, additional validation was performed on held-out test data. The AUROC and 95% CI were 0.588 (95% CI, 0.588-0.589), 0.890 (95% CI, 0.888-0.891), and 0.898 (95% CI, 0.897-0.899), for MEWS of 5, Can-EWS V1, and the deployed model Can-EWS V2, respectively. Can-EWS V2 outperformed other approaches for specificities, positive predictive values, negative predictive values, and the number of false alarms per day at the same sensitivity level on the held-out test data. CONCLUSIONS: We have developed and validated a deep learning-based EWS for cancer patients using the original values and differences between consecutive measurements of basic vital signs. The Can-EWS has acceptable discriminatory power and sensitivity, with extremely decreased false alarms compared with MEWS.

The Effectiveness of Early Enteral Nutrition on Clinical Outcomes in Critically Ill Sepsis Patients: A Systematic Review.

The optimal timing of enteral nutrition (EN) in sepsis patients is controversial among societal guidelines. We aimed to evaluate the evidence of early EN's impact on critically ill sepsis patients' clinical outcomes. We searched the MEDLINE, Embase, CINAHL, Cochrane Library, ClinicalTrials.gov, and ICTRP databases on 10 March 2023. We included studies published after 2004 that compared early EN versus delayed EN in sepsis patients. We included randomized controlled trials (RCTs), non-RCTs, cohort studies, and case-control studies. Forest plots were used to summarize risk ratios (RRs), including mortality and mean difference (MD) of continuous variables such as intensive care unit (ICU) length of stay and ventilator-free days. We identified 11 eligible studies with sample sizes ranging from 31 to 2410. The RR of short-term mortality from three RCTs was insignificant, and the MD of ICU length of stay from two RCTs was -2.91 and -1.00 days (95% confidence interval [CI], -5.53 to -0.29 and -1.68 to -0.32). Although the RR of intestinal-related complications from one RCT was 3.82 (95% CI, 1.43 to 10.19), indicating a significantly higher risk for the early EN group than the control group, intestinal-related complications of EN reported in five studies were inconclusive. This systematic review did not find significant benefits of early EN on mortality in sepsis patients. Evidence, however, is weak due to inconsistent definitions, heterogeneity, risk of bias, and poor methodology in the existing studies.

Influence of gender on age-associated in-hospital mortality in patients with sepsis and septic shock: a prospective nationwide multicenter cohort study.

BACKGROUND: Numerous epidemiological studies investigating gender-dependent clinical outcomes in sepsis have shown conflicting evidence. This study aimed to investigate the effect of gender on in-hospital mortality due to sepsis according to age group. METHODS: This study used data from the Korean Sepsis Alliance, an ongoing nationwide prospective multicenter cohort from 19 participating hospitals in South Korea. All adult patients diagnosed with sepsis in the emergency departments of the participating hospitals between September 2019 and December 2021 were included in the analysis. Clinical characteristics and outcomes were compared between male and female. Eligible patients were stratified by age into 19-50 years, 50-80 years, and ≥ 80 years old individuals. RESULTS: During the study period, 6442 patients were included in the analysis, and 3650 (56.7%) were male. The adjusted odds ratio (OR) [95% confidence interval (CI)] for in-hospital mortality for male compared with female was 1.15 (95% CI = 1.02-1.29). Interestingly, in the age 19-50 group, the risk of in-hospital mortality for males was significantly lower than that of females [0.57 (95% CI = 0.35-0.93)]. For female, the risk of death remained relatively stable until around age 80 (P for linearity = 0.77), while in males, there was a linear increase in the risk of in-hospital death until around age 80 (P for linearity < 0.01). Respiratory infection (53.8% vs. 37.4%, p < 0.01) was more common in male, whereas urinary tract infection (14.7% vs. 29.8%, p < 0.01) was more common in female. For respiratory infection, male had significantly lower in-hospital mortality than female in the age 19-50 groups (adjusted OR = 0.29, 95% CI = 0.12-0.69). CONCLUSIONS: Gender may influence age-associated sepsis outcomes. Further studies are needed to replicate our findings and fully understand the interaction of gender and age on the outcomes of patients with sepsis.

Prognostic significance of respiratory quotient in patients undergoing extracorporeal cardiopulmonary resuscitation in Korea.

BACKGROUND: Respiratory quotient (RQ) may be used as a tissue hypoxia marker in various clinical settings but its prognostic significance in patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) is not known. METHODS: Medical records of adult patients admitted to the intensive care units after ECPR in whom RQ could be calculated from May 2004 to April 2020 were retrospectively reviewed. Patients were divided into good neurologic outcome and poor neurologic outcome groups. Prognostic significance of RQ was compared to other clinical characteristics and markers of tissue hypoxia. RESULTS: During the study period, 155 patients were eligible for analysis. Of them, 90 (58.1%) had a poor neurologic outcome. The group with poor neurologic outcome had a higher incidence of out-of-hospital cardiac arrest (25.6% vs. 9.2%, P=0.010) and longer cardiopulmonary resuscitation to pump-on time (33.0 vs. 25.2 minutes, P=0.001) than the group with good neurologic outcome. For tissue hypoxia markers, the group with poor neurologic outcome had higher RQ (2.2 vs. 1.7, P=0.021) and lactate levels (8.2 vs. 5.4 mmol/L, P=0.004) than the group with good neurologic outcome. On multivariable analysis, age, cardiopulmonary resuscitation to pump-on time, and lactate levels above 7.1 mmol/L were significant predictors for a poor neurologic outcome but not RQ. CONCLUSIONS: In patients who received ECPR, RQ was not independently associated with poor neurologic outcome.

The Profile of Early Sedation Depth and Clinical Outcomes of Mechanically Ventilated Patients in Korea.

BACKGROUND: Current international guidelines recommend against deep sedation as it is associated with worse outcomes in the intensive care unit (ICU). However, in Korea the prevalence of deep sedation and its impact on patients in the ICU are not well known. METHODS: From April 2020 to July 2021, a multicenter, prospective, longitudinal, noninterventional cohort study was performed in 20 Korean ICUs. Sedation depth extent was divided into light and deep using a mean Richmond Agitation-Sedation Scale value within the first 48 hours. Propensity score matching was used to balance covariables; the outcomes were compared between the two groups. RESULTS: Overall, 631 patients (418 [66.2%] and 213 [33.8%] in the deep and light sedation groups, respectively) were included. Mortality rates were 14.1% and 8.4% in the deep and light sedation groups (P = 0.039), respectively. Kaplan-Meier estimates showed that time to extubation (P < 0.001), ICU length of stay (P = 0.005), and death (P = 0.041) differed between the groups. After adjusting for confounders, early deep sedation was only associated with delayed time to extubation (hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.55-0.80; P < 0.001). In the matched cohort, deep sedation remained significantly associated with delayed time to extubation (HR, 0.68; 95% CI, 0.56-0.83; P < 0.001) but was not associated with ICU length of stay (HR, 0.94; 95% CI, 0.79-1.13; P = 0.500) and in-hospital mortality (HR, 1.19; 95% CI, 0.65-2.17; P = 0.582). CONCLUSION: In many Korean ICUs, early deep sedation was highly prevalent in mechanically ventilated patients and was associated with delayed extubation, but not prolonged ICU stay or in-hospital death.

Optimal Position of a Femorojugular Cannulation for Venovenous Extracorporeal Membrane Oxygenation in Acute Respiratory Distress Syndrome.

BACKGROUND: This study aimed to determine the optimal position of venovenous extracorporeal membrane oxygenation (V-V ECMO) draining cannulas for refractory respiratory failure based on short-term clinical results. METHODS: In total, 278 patients underwent V-V ECMO at our hospital between 2012 and 2020. Those who underwent V-V ECMO with a femorojugular configuration were included. In the final cohort, 96 patients were divided into groups based on the draining cannula tip site: an inferior vena cava (IVC) group (n = 35) and a right atrium (RA) group (n = 61). The primary outcome was the change in fluid balance and ratio of awake ECMO 72 hours after V-V ECMO initiation. RESULTS: The only significant difference in baseline characteristics before V-V ECMO between the groups was a higher PaO2/FiO2 ratio in the RA group than in the IVC group (79.1 ± 26.21 vs 64.7 ± 14, P = .001). The degree of recirculation and arterial oxygenation, 90-day mortality, and clinical outcomes were similar between the groups. However, more patients achieved negative intake and output fluid balances (57.4% vs 31.4%, P = .01) and reductions in body weight (68.9% vs 40%, P = .006) in the RA group. At 72 hours after Vfemoral-Vjugular ECMO initiation, more patients in the RA group than in the IVC group were managed under awake ECMO (42.6% vs 22.9%, P =.047). CONCLUSIONS: Placement of a V-V ECMO draining cannula in the RA rather than the IVC is more effective for restricted fluid management and awake ECMO without significant recirculation.

Antibiogram of Multidrug-Resistant Bacteria Based on Sepsis Onset Location in Korea: A Multicenter Cohort Study.

BACKGROUND: Administration of adequate antibiotics is crucial for better outcomes in sepsis. Because no uniform tool can accurately assess the risk of multidrug-resistant (MDR) pathogens, a local antibiogram is necessary. We aimed to describe the antibiogram of MDR bacteria based on locations of sepsis onset in South Korea. METHODS: We performed a prospective observational study of adult patients diagnosed with sepsis according to Sepsis-3 from 19 institutions (13 tertiary referral and 6 university-affiliated general hospitals) in South Korea. Patients were divided into four groups based on the respective location of sepsis onset: community, nursing home, long-term-care hospital, and hospital. Along with the antibiogram, risk factors of MDR bacteria and drug-bug match of empirical antibiotics were analyzed. RESULTS: MDR bacteria were detected in 1,596 (22.7%) of 7,024 patients with gram-negative predominance. MDR gram-negative bacteria were more commonly detected in long-term-care hospital- (30.4%) and nursing home-acquired (26.3%) sepsis, whereas MDR gram-positive bacteria were more prevalent in hospital-acquired (10.9%) sepsis. Such findings were consistent regardless of the location and tier of hospitals throughout South Korea. Patients with long-term-care hospital-acquired sepsis had the highest risk of MDR pathogen, which was even higher than those with hospital-acquired sepsis (adjusted odds ratio, 1.42; 95% confidence interval, 1.15-1.75) after adjustment of risk factors. The drug-bug match was lowest in patients with long-term-care hospital-acquired sepsis (66.8%). CONCLUSION: Gram-negative MDR bacteria were more common in nursing home- and long-term-care hospital-acquired sepsis, whereas gram-positive MDR bacteria were more common in hospital-acquired settings in South Korea. Patients with long-term-care hospital-acquired sepsis had the highest the risk of MDR bacteria but lowest drug-bug match of initial antibiotics. We suggest that initial antibiotics be carefully selected according to the onset location in each patient.

Real-Time Measurements of Relative Tidal Volume and Stroke Volume Using Electrical Impedance Tomography with Spatial Filters: A Feasibility Study in a Swine Model Under Normal and Reduced Ventilation.

Continuous monitoring of both hemodynamic and respiratory parameters would be beneficial to patients, e.g., those in intensive care unit. The objective of this exploratory animal study was to test the feasibility of simultaneous measurements of relative tidal volume (rTV) and relative stroke volume (rSV) using an electrical impedance tomography (EIT) device equipped with a new real-time source separation algorithm implemented as two spatial filters. Five pigs were anesthetized and mechanically ventilated. The supplied tidal volume from a mechanical ventilator was reduced to 70, 50 and 30% from the 100% normal volume to simulate hypoventilation. The respiratory volume signal and cardiac volume signal were generated by applying the spatial filters to the acquired EIT data, from which values of rTV and rSV were extracted. The measured rTV values were compared with the TV values from the mechanical ventilator using the four-quadrant concordance analysis method. For changes in TV, the concordance rate in each animal ranged from 81.8% to 100%, while it was 92.5% when the data from all five animals were pooled together. When the measured rTV values for each animal were scaled to the absolute TVEIT values in mL using the TVVent data from the mechanical ventilator, the smallest 95% limits of agreement (LoA) were - 6.04 and 7.44 mL for the 70% ventilation level, and the largest 95% LoA were - 18.1 and 19.4 mL for the 50% ventilation level. The percentage error between TVEIT and TVVent was 10.3%. Although similar statistical analyses on rSV data could not be performed due to limited intra-animal variability, changes in rSV values measured by the EIT device were comparable to those measured by an invasive hemodynamic monitor. In this animal study, we were able to demonstrate the feasibility of an EIT device for noninvasive and simultaneous measurements of rTV and rSV in real time. However, the performance of the real-time source separation method needs to be further validated on animals and human subjects, particularly over a wide range of SV values. Future clinical studies are needed to assess the potential usefulness of the new method in dynamic cardiopulmonary monitoring and explore other clinical applications.

HYPOTENSION AT THE TIME OF SEPSIS RECOGNITION IS NOT ASSOCIATED WITH INCREASED MORTALITY IN SEPSIS PATIENTS WITH NORMAL LACTATE LEVELS.

ABSTRACT: Background and Objective: Although sepsis is heterogeneous, data on sepsis patients with normal lactate levels are very limited. We explored whether hypotension at the time of sepsis recognition (i.e., time zero) was significant in terms of survival when lactate levels were normal in sepsis patients. Patients and Design: This was a prospective multicenter observational study conducted in 19 hospitals (20 intensive care units [ICUs]). Adult sepsis patients with normal lactate levels (≤2 mmol/L) admitted to ICUs were divided by the mean arterial pressure at time zero into hypotensive (<65 mm Hg) and nonhypotensive groups (≥65 mm Hg). Measurements and Results: Of 2,032 patients with sepsis (not septic shock), 617 with normal lactate levels were included in the analysis. The hypotensive group (n = 237) was characterized by higher rates of abdominal or urinary infections, and bacteremia, whereas the nonhypotensive group (n = 380) was characterized by higher rates of pulmonary infections and systemic inflammatory response. However, the Simplified Acute Physiology Score 3 and Sequential Organ Failure Assessment score (excluding the cardiovascular score) were not different between the groups. During sepsis resuscitation, the rates of antibiotic administration within 1, 3, and 6 h of time zero were higher in the hypotensive than nonhypotensive group ( P < 0.05 for all time points), and the amounts of pre-ICU fluids given were also higher in the hypotensive group. However, despite a higher rate of vasopressor use in the hypotensive group, ICU and in-hospital mortality rates were not different between the groups (12.7% vs. 13.9% [ P = 0.648] and 19.4% vs. 22.4% [ P = 0.382], respectively). In multivariable analysis, the use of appropriate antibiotics and early lactate measurement were significant risk factors for in-hospital mortality. Conclusions: In sepsis patients with normal lactate levels, neither hypotension nor vasopressor use adversely impacted the hospital outcome. Our results emphasize the importance of early interventions and appropriate use of antibiotics regardless of whether a patient is or is not hypotensive.

Systematized and efficient: organization of critical care in the future.

Since the advent of critical care in the twentieth century, the core elements that are the foundation for critical care systems, namely to care for critically ill and injured patients and to save lives, have evolved enormously. The past half-century has seen dramatic advancements in diagnostic, organ support, and treatment modalities in critical care, with further improvements now needed to achieve personalized critical care of the highest quality. For critical care to be even higher quality in the future, advancements in the following areas are key: the physical ICU space; the people that care for critically ill patients; the equipment and technologies; the information systems and data; and the research systems that impact critically ill patients and families. With acutely and critically ill patients and their families as the absolute focal point, advancements across these areas will hopefully transform care and outcomes over the coming years.

Safety and feasibility of continuous ketamine infusion for analgosedation in medical and cardiac ICU patients who received mechanical ventilation support: A retrospective cohort study.

PURPOSE: To assess the effect of continuous ketamine administration in patients admitted to medical and cardiac intensive care units (ICUs) and received mechanical ventilation support. METHODS: We conducted a retrospective cohort study between March 2012 and June 2020 at an academy-affiliated tertiary hospital. Adult patients who received mechanical ventilation support for over 24 h and continuous ketamine infusion for at least 8 h were included. The primary outcome was immediate hemodynamic safety after continuous ketamine infusion. The secondary outcomes included immediate delirium, pain, and use of sedation. RESULTS: Of all 12,534 medical and cardiac ICU patients, 564 were eligible for the analysis. Ketamine was used for 33.3 (19.0-67.5) h and the median continuous infusion dose was 0.11 (0.06-0.23) mcg/kg/h. Of all patients, 469 (83.2%) received continuous ketamine infusion concomitant with analgosedation. Blood pressure and vasopressor inotropic scores did not change after continuous ketamine infusion. Heart rate decreased significantly from 106.9 (91.4-120.9) at 8 h before ketamine initiation to 99.8% (83.9-114.4) at 24 h after ketamine initiation. In addition, the respiratory rate decreased from 21.7 (18.6-25.4) at 8 h before ketamine initiation to 20.1 (17.0-23.0) at 24 h after ketamine initiation. Overall opioid usage was significantly reduced: 3.0 (0.0-6.0) mcg/kg/h as fentanyl equivalent dose at 8 h before ketamine initiation to 1.0 (0.0-4.1) mcg/kg/h as fentanyl equivalent dose at 24 h post-ketamine initiation. However, the use of sedatives and antipsychotic medications did not decrease. In addition, ketamine did not increase the incidence of delirium within 24 h after ketamine infusion. CONCLUSION: Ketamine may be a safe and feasible analgesic for medical and cardiac ICU patients who received mechanical ventilation support as an opioid-sparing agent without adverse hemodynamic effects.

Impact of protocolized fluid management on electrolyte stability in patients undergoing continuous renal replacement therapy.

Objective: Continuous renal replacement therapy (CRRT) is the standard treatment for critically ill patients with acute kidney injury (AKI). Electrolyte disturbance such as hypokalemia or hypophosphatemia occurs paradoxically in patients undergoing CRRT due to high clearance. We developed a fluid management protocol for dialysate and replacement fluid that depends on serum electrolytes and focuses on potassium and phosphate levels to prevent electrolyte disturbance during CRRT. The impact of our new fluid protocol on electrolyte stability was evaluated. Methods: Adult patients who received CRRT between 2013 and 2017 were included. Patients treated 2 years before (2013-2014; pre-protocol group) and 2 years following development of the fluid protocol (2016-2017; protocol group) were compared. The primary outcomes were individual coefficient of variation (CV) and abnormal event rates of serum phosphate and potassium. Secondary outcomes were frequency of electrolyte replacement and incidence of cardiac arrhythmias. Individual CV and abnormal event rates for each electrolyte were analyzed using the Wilcoxon rank-sum test and Chi-square test with Yates' continuity correction. Results: A total of 1,448 patients was included. Both serum phosphate and potassium were higher in the protocol group. The CVs of serum phosphate (pre-protocol vs. protocol, 0.275 [0.207-0.358] vs. 0.229 [0.169-0.304], p < 0.01) and potassium (0.104 [0.081-0.135] vs. 0.085 [0.064-0.110], p < 0.01) were significantly lower in the protocol group. The abnormal event rates of serum phosphate (rate [95% CI], 0.410 [0.400-0.415] vs. 0.280 [0.273-0.286], p < 0.01) and potassium (0.205 [0.199-0.211] vs. 0.083 [0.079-0.087], p < 0.01) were also significantly lower in the protocol group. Conclusion: The protocolized management of fluid in CRRT effectively prevented hypophosphatemia and hypokalemia by inducing excellent stability of serum phosphate and potassium levels.

Severity-Adjusted Dexamethasone Dosing and Tocilizumab Combination for Severe COVID-19.

PURPOSE: Real-world experience with tocilizumab in combination with dexamethasone in patients with severe coronavirus disease (COVID-19) needs to be investigated. MATERIALS AND METHODS: A retrospective cohort study was conducted to evaluate the effect of severity-adjusted dosing of dexamethasone in combination with tocilizumab for severe COVID-19 from August 2020 to August 2021. The primary endpoint was 30-day clinical recovery, which was defined as no oxygen requirement or referral after recovery. RESULTS: A total of 66 patients were evaluated, including 33 patients in the dexamethasone (Dexa) group and 33 patients in the dexamethasone plus tocilizumab (DexaToci) group. The DexaToci group showed a statistically significant benefit in 30-day clinical recovery, compared to the Dexa group (p=0.024). In multivariable analyses, peak FiO2 within 3 days and tocilizumab combination were consistently significant for 30-day recovery (all p<0.05). The DexaToci group showed a significantly steeper decrease in FiO2 (-4.2±2.6) than the Dexa group (-2.7±2.6; p=0.021) by hospital day 15. The duration of oxygen requirement was significantly shorter in the DexaToci group than the Dexa group (median, 10.0 days vs. 17.0 days; p=0.006). Infectious complications and cellular and humoral immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the convalescence stage were not different between the two groups. CONCLUSION: A combination of severity-adjusted dexamethasone and tocilizumab for the treatment of severe COVID-19 improved clinical recovery without increasing infectious complications or hindering the immune response against SARS-CoV-2.

Impact of Renal Replacement Therapy on Mortality and Renal Outcomes in Critically Ill Patients with Acute Kidney Injury: A Population-Based Cohort Study in Korea between 2008 and 2015.

The outcomes depending on the type of renal replacement therapy (RRT) or pre-existing kidney disease in critically ill patients with acute kidney injury (AKI) have not been fully elucidated. All adult intensive care unit patients with AKI in Korea from 2008 to 2015 were screened. A total of 124,182 patients, including 21,165 patients with pre-existing kidney disease, were divided into three groups: control (no RRT), dialysis, and continuous RRT (CRRT). In-hospital mortality and progression to end-stage kidney disease (ESKD) were analyzed according to the presence of pre-existing kidney disease. The CRRT group had a higher risk of in-hospital mortality. Among the patients with pre-existing kidney disease, the dialysis group had a lower risk of in-hospital mortality compared to other groups. The risk of ESKD was higher in the dialysis and CRRT groups compared to the control group. In the CRRT group, the risk of ESKD was even higher in patients without pre-existing kidney disease. Although both dialysis and CRRT groups showed a higher incidence of ESKD, in-hospital mortality was lower in the dialysis group, especially in patients with pre-existing kidney disease. Our study supports that RRT and pre-existing kidney disease may be important prognostic factors for overall and renal outcomes in patients with AKI.