Kidney Doppler Ultrasonography in Critical Care Nephrology.

Color pulsed-wave Doppler ultrasound (CPWD-US) emerges as a pivotal tool in intensive care units (ICUs) for diagnosing acute kidney injury (AKI) swiftly and non-invasively. Its bedside accessibility allows for rapid assessments, making it a primary imaging modality for AKI characterization. Furthermore, CPWD-US serves as a guiding instrument for key diagnostic-interventional procedures such as renal needle biopsy and percutaneous nephrostomy, while also facilitating therapy response monitoring and AKI progression tracking. This review shifts focus towards the integration of renal ultrasound into ICU workflows, offering contemporary insights into its utilization through a diagnostic-standard-oriented approach. By presenting a flow chart, this review aims to provide practical guidance on the appropriate use of point-of-care ultrasound (POC-US) in critical care scenarios, enhancing diagnostic precision, patient management, and safety, albeit amidst a backdrop of limited evidence regarding long-term outcomes.

Advanced chronic kidney disease after surgery and the contribution of acute kidney disease: a national observational cohort study.

BACKGROUND: Limited knowledge exists regarding long-term renal outcomes after noncardiac surgery. This study investigated the incidence of, and risk factors for, developing advanced chronic kidney disease (CKD) and major adverse kidney events within 1 yr of surgery in a nationwide cohort. METHODS: Adults without renal dysfunction before noncardiac surgery in Sweden were included between 2007 and 2013 in this observational multicentre cohort study. We analysed data from a national surgical database linked to several national and quality outcome registries. Associations of perioperative risk factors with advanced CKD (estimated glomerular filtration rate [eGFR] <30 ml min-1 1.73 m-2) and major adverse kidney events within 1 yr (MAKE365, comprising eGFR <30 ml min-1 1.73 m-2, chronic dialysis, death) were quantified. RESULTS: Of 237,124 patients, 1597 (0.67%) developed advanced CKD and 16,789 (7.1%) developed MAKE365. Risk factors for advanced CKD included higher ASA physical status, urological surgery, extended surgical duration, prolonged postoperative hospital stay, repeated surgery, and postoperative use of renin-angiotensin-aldosterone system blockers. Advanced acute kidney disease (AKD) (eGFR <30 ml min-1 1.73 m-2 within 90 postoperative days) occurred in 1661 (0.70%) patients and was associated with advanced CKD (subdistribution hazard ratio [SHR] 44.5, 95% confidence interval [CI] 38.7-51.1) and MAKE365 (hazard ratio [HR] 6.60, 95% CI 6.07-7.17). Among patients with advanced AKD after surgery 36% developed advanced CKD at 1 yr after surgery and 51% developed MAKE365. CONCLUSIONS: Advanced CKD within 1 yr after surgery is uncommon but clinically important in patients without preoperative renal dysfunction. Advanced AKD after surgery constitutes a major risk factor for advanced CKD and MAKE365.

Incidence and risk factors of peri-operative stroke in major non-cardiovascular, non-neurologic surgery-A retrospective register-based cohort study.

BACKGROUND: Peri-operative stroke is a rare but serious surgical complication. Both overt and covert stroke, occurring in approximately 0.1% and 7% of cases, respectively, are associated with significant long-term effects and increased morbidity. METHODS: Retrospective register data for patients >18 years old, presenting for major non-cardiovascular, non-neurosurgical and non-ambulatory surgical procedures at 23 hospitals in Sweden between 2007 and 2014 was collected and linked with various quality registers. The primary outcome was stroke within 30 days from surgery. Using multivariable logistic regression, significant independent risk factors influencing the primary outcome were identified and their adjusted odds ratios (ORs) were calculated. Mortality was assessed, along with the composite score of days alive and at home within 30 days after surgery (DAH 30). RESULTS: In total, 318,017 patients were included, with 687 (0.22%) suffering a stroke within 30 days of surgery. The strongest significant risk factors included: increasing ASA-class (OR [95% confidence interval, CI]: 2.23 [1.53-3.36], 3.91 [2.68-5.93] and 7.82 [5.03-12.5] for ASA 2, 3 and 4, respectively) and age (OR [95% CI]: 4.47 [2.21-10.3], 9.9 [5.15-22.1], 16.3 [8.48-36.5] and 21 [10.6-48.1], for age 45-59, 60-74, 75-89 and >90, respectively), along with non-elective procedures, male gender and a history of cerebrovascular disease (OR [95%]: 2.72 [2.25-3.27]). Mortality was increased and DAH 30 was reduced in patients suffering a stroke. CONCLUSIONS: Increasing ASA-class and age was clearly associated with an increased risk of peri-operative stroke, which in turn was associated with increased mortality and poorer outcome. Detailed pre-operative risk stratification and individualised peri-operative management could potentially improve patient-centred outcomes and, in turn, have positive implications for public health.

Association of Preoperative Renal-Resistive Index With Long-term Renal and Cardiovascular Outcomes After Cardiac Surgery.

OBJECTIVE: To investigate the association of elevated preoperative renal-resistive index (RRI) with persistent renal dysfunction, major adverse kidney events (MAKE), and major adverse cardiovascular events (MACE) after cardiac surgery. DESIGN: Observational cohort study. SETTING: University hospital. PARTICIPANTS: Ninety-six adult patients undergoing cardiac surgery. INTERVENTIONS: RRI measurement the day before surgery. MEASUREMENTS AND MAIN RESULTS: Fifty-eight patients (60%) had elevated RRI ≥0.70. Five years after surgery, persistent renal dysfunction (sustained decline in estimated glomerular filtration rate ≥25%) had occurred in 25 patients (26%), MAKE (persistent renal dysfunction, renal replacement therapy, or death) in 34 (35%), and MACE (myocardial infarction, unstable angina, decompensated heart failure, stroke, or cardiovascular death) in 28 (29%). RRI was higher in patients who developed persistent renal dysfunction (median, 0.78 [IQR, 0.74-0.82] v 0.70 [0.66-0.77], p = 0.001), MAKE (0.77 [0.72-0.81] v 0.68 [0.65-0.76], p = 0.002), and MACE (0.77 [0.72-0.81] v 0.70 [0.66-0.77], p = 0.006). Patients with elevated RRI had a significantly higher cumulative incidence of all long-term outcomes. After adjustment for baseline renal function and heart failure, elevated RRI was associated with persistent renal dysfunction (hazard ratio [HR], 5.82 [95% CI, 1.71-19.9]), MAKE (HR, 4.21 [1.59-11.1]), and MACE (HR, 2.81 [1.03-7.65]). CONCLUSIONS: Elevated preoperative RRI is associated with persistent renal dysfunction, MAKE, and MACE after cardiac surgery. Preoperative RRI may be used for long-term risk assessment in patients undergoing cardiac surgery.

Individual and neighborhood risk factors of hospital admission and death during the COVID-19 pandemic: a population-based cohort study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) disproportionately affects minority populations in the USA. Sweden - like other Nordic countries - have less income and wealth inequality but lacks data on the socioeconomic impact on the risk of adverse outcomes due to COVID-19. METHODS: This population-wide study from March 2020 to March 2022 included all adults in Stockholm, except those in nursing homes or receiving in-home care. Data sources include hospitals, primary care (individual diagnoses), the Swedish National Tax Agency (death dates), the Total Population Register "RTB" (sex, age, birth country), the Household Register (size of household), the Integrated Database For Labor Market Research "LISA" (educational level, income, and occupation), and SmiNet (COVID data). Individual exposures include education, income, type of work and ability to work from home, living area and living conditions as well as the individual country of origin and co-morbidities. Additionally, we have data on the risks associated with living areas. We used a Cox proportional hazards model and logistic regression to estimate associations. Area-level covariates were used in a principal component analysis to generate a measurement of neighborhood deprivation. As outcomes, we used hospitalization and death due to COVID-19. RESULTS: Among the 1,782,125 persons, male sex, comorbidities, higher age, and not being born in Sweden increase the risk of hospitalization and death. So does lower education and lower income, the lowest incomes doubled the risk of death from COVID-19. Area estimates, where the model includes individual risks, show that high population density and a high percentage of foreign-born inhabitants increased the risk of hospitalization. CONCLUSIONS: Segregation and deprivation are public health issues elucidated by COVID-19. Neighborhood deprivation, prevalent in Stockholm, adds to individual risks and is associated with hospitalization and death. This finding is paramount for governments, agencies, and healthcare institutions interested in targeted interventions.

COVID-19 and comedications in atrial fibrillation-a case-control study in Stockholm.

To test the main hypothesis that anticoagulation reduces risk of hospitalization, intensive care unit (ICU) admission and death in COVID-19. Nested case-control study among patients with atrial fibrillation (AF) in Stockholm. COVID-19 cases were matched to five disease-free controls with same sex, born within ± 1 years. Source population was individuals in Stockholm with AF 1997-2020. Swedish regional and national registers are used. National registers cover hospitals and outpatient clinics, local registers cover primary care. Records were linked through the personal identity number assigned to each Swedish resident. Cases were individuals with COVID-19 (diagnosis, ICU admission, or death). The AF source population consisted of 179,381 individuals from which 7548 cases were identified together with 37,145 controls. The number of cases (controls) identified from hospitalization, ICU admission or death were 5916 (29,035), 160 (750) and 1472 (7,360). The proportion of women was 40% for hospitalization and death, but 20% and 30% for admission to ICU in wave one and two, respectively. Primary outcome was mortality, secondary outcome was hospitalization, tertiary outcome was ICU admission, all with COVID-19. Odds ratios (95% confidence interval) for antithrombotics were 0.79 (0.66-0.95) for the first wave and 0.80 (0.64-1.01) for the second wave. Use of anticoagulation among patients with arrythmias infected with COVID-19 is associated with lower risk of hospitalization and death. If further COVID-variants emerge, or other infections with prothrombotic properties, this emphasize need for physicians to ensure compliance among vulnerable patients.

Clinical phenotypes and outcomes of SARS-CoV-2, influenza, RSV and seven other respiratory viruses: a retrospective study using complete hospital data.

BACKGROUND: An understanding of differences in clinical phenotypes and outcomes COVID-19 compared with other respiratory viral infections is important to optimise the management of patients and plan healthcare. Herein we sought to investigate such differences in patients positive for SARS-CoV-2 compared with influenza, respiratory syncytial virus (RSV) and other respiratory viruses. METHODS: We performed a retrospective cohort study of hospitalised adults and children (≤15 years) who tested positive for SARS-CoV-2, influenza virus A/B, RSV, rhinovirus, enterovirus, parainfluenza viruses, metapneumovirus, seasonal coronaviruses, adenovirus or bocavirus in a respiratory sample at admission between 2011 and 2020. RESULTS: A total of 6321 adult (1721 SARS-CoV-2) and 6379 paediatric (101 SARS-CoV-2) healthcare episodes were included in the study. In adults, SARS-CoV-2 positivity was independently associated with younger age, male sex, overweight/obesity, diabetes and hypertension, tachypnoea as well as better haemodynamic measurements, white cell count, platelet count and creatinine values. Furthermore, SARS-CoV-2 was associated with higher 30-day mortality as compared with influenza (adjusted HR (aHR) 4.43, 95% CI 3.51 to 5.59), RSV (aHR 3.81, 95% CI 2.72 to 5.34) and other respiratory viruses (aHR 3.46, 95% CI 2.61 to 4.60), as well as higher 90-day mortality, ICU admission, ICU mortality and pulmonary embolism in adults. In children, patients with SARS-CoV-2 were older and had lower prevalence of chronic cardiac and respiratory diseases compared with other viruses. CONCLUSIONS: SARS-CoV-2 is associated with more severe outcomes compared with other respiratory viruses, and although associated with specific patient and clinical characteristics at admission, a substantial overlap precludes discrimination based on these characteristics.

Patterns and determinants of blood transfusion in intensive care in Sweden between 2010 and 2018: A nationwide, retrospective cohort study.

BACKGROUND: Intensive care unit (ICU) patients are transfused with blood products for a number of reasons, from massive ongoing hemorrhage, to mild anemia following blood sampling, combined with bone marrow depression due to critical illness. There's a paucity of data on transfusions in ICUs and most studies are based on audits or surveys. The aim of this study was to provide a complete picture of ICU-related transfusions in Sweden. METHODS: We conducted a register based retrospective cohort study with data on all adult patient admissions from 82 of 84 Swedish ICUs between 2010 and 2018, as recorded in the Swedish Intensive Care Register. Transfusions were obtained from the SCANDAT-3 database. Descriptive statistics were computed, characterizing transfused and nontransfused patients. The distribution of blood use comparing different ICUs was investigated by computing the observed proportion of ICU stays with a transfusion, as well as the expected proportion. RESULTS: In 330,938 ICU episodes analyzed, at least one transfusion was administered for 106,062 (32%). For both red-cell units and plasma, the fraction of patients who were transfused decreased during the study period from 31.3% in 2010 to 24.6% in 2018 for red-cells, and from 16.6% in 2010 to 9.4% in 2018 for plasma. After adjusting for a range of factors, substantial variation in transfusion frequency remained, especially for plasma units. CONCLUSION: Despite continuous decreases in utilization, transfusions remain common among Swedish ICU patients. There is considerable unexplained variation in transfusion rates. More research is needed to establish stronger critiera for when to transfuse ICU patients.

Risk factors for COVID-19-related death, hospitalization and intensive care: a population-wide study of all inhabitants in Stockholm.

Since the beginning of the Covid-19 pandemic, the scientific community has explored determinants of Covid 19 disease severity. However, the majority of studies are based on in-hospital patients with high risk of collider- or selection bias. The present investigation details risk factors associated with overall mortality, hospitalization and intensive care unit (ICU) admission in Covid-19 infections, with complete population coverage and high-resolution data on patient characteristics and comorbid conditions This population-based observational study comprises all residents 18 years and older in Stockholm Region-1.8 million inhabitants-using the real-time Covid-19 monitoring framework. The observation period lasted between March 1 to December 31, 2020. Hazard ratios (HR) for risk factors of Covid-19 disease severity were assessed using Cox proportional hazard models. In total, 3322 deaths, 11,508 hospitalizations and 1423 ICU-admissions related to Covid-19 occurred during the study period. Kidney failure, diabetes and obesity increased risk of mortality and so did heart failure and ischemic heart disease. However, atrial fibrillation and hypertension did not. Risk of hospitalization follow a similar pattern, whereas admission to intensive care differs; triage processes where clearly present as certain co-morbid conditions were associated with lower ICU admission. Observed differences in risk of mortality and hospitalization among patients with Covid 19 raise important questions about potentially protective comedication which will be further addressed using the real-time Covid-19 monitoring framework.

Hospital costs and factors associated with days alive and at home after surgery (DAH30 ).

OBJECTIVE: To assess the relationships of patient and surgical factors and hospital costs with the number of days alive and at home during the 30 days following surgery (DAH30 ). DESIGN: Retrospective cohort study; analysis of Medibank Private health insurance hospital claims data, Australia, 1 January 2016 - 31 December 2017. SETTING, PARTICIPANTS: Admissions of adults (18 years or older) to hospitals for elective or emergency inpatient surgery with anaesthesia covered by private health insurance, Australia, 1 January 2016 - 31 December 2017. MAIN OUTCOME MEASURES: Associations between DAH30 and total hospital costs, and between DAH30 and surgery risk factors. RESULTS: Complete data were available for 126 788 of 181 281 eligible patients (69.9%); their median age was 62 years (IQR, 47-73 years), 72 872 were women (57%), and 115 117 had undergone elective surgery (91%). The median DAH30 was 27.1 days (IQR, 24.2-28.8 days), the median hospital cost per patient was $10 358 (IQR, $6624-20 174). The association between DAH30 and total hospital costs was moderate (Spearman ρ = -0.60; P < 0.001). Median DAH30 declined with age, comorbidity score, ASA physical status score, and surgical severity and duration, and was also lower for women. CONCLUSIONS: DAH30 is a validated, patient-centred outcome measure of post-surgical outcomes; higher values reflect shorter hospital stays and fewer serious complications, re-admissions, and deaths. DAH30 can be used to benchmark quality of surgical care and to monitor quality improvement programs for reducing the costs of surgical and other peri-operative care.

Postoperative complications and myocardial injury in patients receiving air or oxygen. Prospective, randomised and pilot study.

BACKGROUND: Supplementary oxygen is administered during anaesthesia to increase oxygen delivery and prevent hypoxia. Recent studies have questioned this routine. In this pilot study, our main aim was to investigate if 21% oxygen compared to ≥50% reduces the risk of postoperative complications and myocardial injury. METHODS: In this pragmatic, multicentre, single-blind study, patients undergoing vascular surgery were randomised to receive a fraction of inspired oxygen (Fi O2 ) ≥ 0.50 and oxygen saturation determined by pulse oximetry (SpO2 ) ≥ 98% (group H) or Fi O2 of 0.21 and SpO2 > 90% (group N) oxygen perioperatively. The primary outcome was a composite outcome of major pre-defined postoperative complications assessed at 30 days. Myocardial injury was determined by serial troponin measurements. Data were analysed using generalised estimating equation, Mann-Whitney U test or chi-squared test, as appropriate. RESULTS: The 191 patients were randomised, and per-protocol principle was used for analyses. At 30-day follow-up, 43 out of 94 patients (46%) had a postoperative complication in group H and 36 out of 90 patients (40%) in group N, p = .46. New myocardial injury was seen in 27% versus 22% in Groups H and N respectively (p = .41). No differences in other outcomes were observed between the groups. Twelve patients (13%) in Group N had SpO2 < 90%, six recovered spontaneously and six required supplemental oxygen. At 1-year follow-up, one patient in group H had died. CONCLUSION: In this pilot study, postoperative complications were similar between the groups in patients randomised to Fi O2 of 0.21 or ≥0.50 and no difference was found in the incidence of new myocardial injury. Larger, prospective adequately powered studies are needed.

Experiences of Renal Replacement Therapy Delivery in Swedish Intensive Care Units during the COVID-19 Pandemic.

BACKGROUND: The COVID-19 pandemic led to a rapidly increased demand for intensive care unit (ICU) and renal replacement therapy (RRT) worldwide. RRT delivery was threatened by a lack of specially trained staff and equipment. We investigated how the first wave of COVID-19 affected RRT delivery in Swedish ICUs. METHODS: An Internet-based questionnaire was sent to ICU lead physicians which included quantitative and qualitative questions regarding RRT demand, equipment availability, and use of continuous renal replacement therapy (CRRT), intermittent haemodialysis (IHD), and peritoneal dialysis (PD) during spring 2020. RESULTS: Twenty-five ICUs responded and these treated 64% of COVID-19 ICU patients in Sweden. ICU capacity increased by 292% (IQR 171-347%). Median peak capacity was reached during the 18th week of the year. RRT use increased overall by 133% and in Stockholm by 188%. 36% of units sequestered CRRT machines. IHD was used in 68% and PD in 12% of ICUs. RRT fluid and filter shortages were experienced by 45% and 33% of wards, respectively; consequently, prescription alterations were made by 24% of ICUs. Calcium solution shortages were reported in 12% of units that led to citrate protocol changes. Staffing shortages resulted in RRT sometimes being delivered by non-RRT-trained staff, safety incidents relating to this occurred, although no patient harm was reported. CONCLUSION: During the first wave of the COVID-19 pandemic, RRT demand increased extensively causing staff and equipment shortages, altered CRRT protocols, and increased use of IHD and PD. The impact on patient outcomes should be assessed to effectively plan for further surge capacity RRT demand.

Can Quantitative Pupillometry be used to Screen for Elevated Intracranial Pressure? A Retrospective Cohort Study.

BACKGROUND: Elevated intracranial pressure (ICP) is a serious complication in brain injury. Because of the risks involved, ICP is not monitored in all patients at risk. Noninvasive screening tools to identify patients with elevated ICP are needed. Anisocoria, abnormal pupillary size, and abnormal pupillary light reflex are signs of high ICP, but manual pupillometry is arbitrary and subject to interrater variability. We have evaluated quantitative pupillometry as a screening tool for elevated ICP. METHODS: We performed a retrospective observational study of the association between Neurological Pupil index (NPi), measured with the Neuroptics NPi-200 pupillometer, and ICP in patients routinely monitored with invasive ICP measurement in the intensive care unit. We performed a nonparametric receiver operator curve analysis for ICP ≥ 20 mm Hg with NPi as a classification variable. We performed a Youden analysis for the optimal NPi cutoff value and recorded sensitivity and specificity for this cutoff value. We also performed a logistic regression with elevated ICP as the dependent variable and NPi as the independent variable. RESULTS: We included 65 patients with invasive ICP monitoring. A total of 2,705 measurements were analyzed. Using NPi as a screening tool for elevated ICP yielded an area under receiver operator curve of 0.72. The optimal mean NPi cutoff value to rule out elevated ICP was ≥ 3.9. The probability of elevated ICP decreased with increasing NPi, with an odds ratio of 0.55 (0.50, 0.61). CONCLUSIONS: Screening with NPi may inform high stakes clinical decisions by ruling out elevated ICP with a high degree of certainty. It may also aid in estimating probabilities of elevated ICP. This can help to weigh the risks of initiating invasive ICP monitoring against the risks of not doing so. Because of its ease of use and excellent interrater reliability, we suggest further studies of NPi as a screening tool for elevated ICP.

HMG-CoA reductase inhibitors and COVID-19 mortality in Stockholm, Sweden: A registry-based cohort study.

BACKGROUND: The relationship between statin treatment and Coronavirus Disease 2019 (COVID-19) mortality has been discussed due to the pleiotropic effects of statins on coagulation and immune mechanisms. However, available observational studies are hampered by study design flaws, resulting in substantial heterogeneity and ambiguities. Here, we aim to determine the relationship between statin treatment and COVID-19 mortality. METHODS AND FINDINGS: This cohort study included all Stockholm residents aged 45 or older (N = 963,876), followed up from 1 March 2020 until 11 November 2020. The exposure was statin treatment initiated before the COVID-19-pandemic, defined as recorded statin dispensation in the Swedish Prescribed Drug Register between 1 March 2019 and 29 February 2020. COVID-19-specific mortality was ascertained from the Swedish Cause of Death Registry. Hazard ratios (HRs) were calculated using multivariable Cox regression models. We further performed a target trial emulation restricted to initiators of statins. In the cohort (51.6% female), 169,642 individuals (17.6%) were statin users. Statin users were older (71.0 versus 58.0 years), more likely to be male (53.3% versus 46.7%), more often diagnosed with comorbidities (for example, ischemic heart disease 23.3% versus 1.6%), more frequently on anticoagulant and antihypertensive treatments, less likely to have a university-level education (34.5% versus 45.4%), and more likely to have a low disposable income (20.6% versus 25.2%), but less likely to reside in crowded housing (6.1% versus 10.3%). A total of 2,545 individuals died from COVID-19 during follow-up, including 765 (0.5%) of the statin users and 1,780 (0.2%) of the nonusers. Statin treatment was associated with a lowered COVID-19 mortality (adjusted HR, 0.88; 95% CI, 0.79 to 0.97, P = 0.01), and this association did not vary appreciably across age groups, sexes, or COVID-19 risk groups. The confounder adjusted HR for statin treatment initiators was 0.78 (95% CI, 0.59 to 1.05, P = 0.10) in the emulated target trial. Limitations of this study include the observational design, reliance on dispensation data, and the inability to study specific drug regimens. CONCLUSIONS: Statin treatment had a modest negative association with COVID-19 mortality. While this finding needs confirmation from randomized clinical trials, it supports the continued use of statin treatment for medical prevention according to current recommendations also during the COVID-19 pandemic.

The Relationship Between Heart Rate and Body Temperature in Critically Ill Patients.

OBJECTIVE: The presence of tachycardia in critically ill patients is frequently used as an indication of severity of illness and to guide treatment decisions but can be influenced by body temperature, thus confounding its interpretation. There are few data available on the relationship between body temperature and heart rate in critically ill patients. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Mixed medical-surgical university hospital ICU. PATIENTS: All patients admitted to the ICU between November 2006 and August 2019. MEASUREMENTS AND MAIN RESULTS: Body temperature was recorded in the electronic medical records at least hourly, from invasive measurements (esophageal probe, indwelling urinary catheter, pulse contour cardiac output monitoring system, or pulmonary artery catheter) or manual tympanic recordings. Heart rate was monitored continuously and hourly values were recorded in the electronic medical record. Change in heart rate with change in body temperature was assessed by extracting pairs of simultaneous body temperature and corresponding heart rate measurements from the electronic medical record: 472,941 simultaneous pairs were obtained from the 9,046 patients admitted during the study period. Each 1°C increase in body temperature between 32.0°C and 42.0°C was associated with an 8.35 beats/min increase in heart rate. Crude linear regression showed an r2 of 0.855 between body temperature and heart rate. Heart rate increased more in females than in males (9.46 vs 7.24 beats/min for each 1°C, p < 0.0001); this relationship was not affected by age or adrenergic drugs. The increase in heart rate was related to the severity of organ dysfunction. CONCLUSIONS: Increase in body temperature is associated with a linear increase in heart rate of 9.46 beats/min/°C in female and 7.24 beats/min/°C in male patients. These observations will help to correctly interpret heart rate values at different body temperatures and enable more accurate evaluation of other factors associated with tachycardia.

Shedding of infectious SARS-CoV-2 by hospitalized COVID-19 patients in relation to serum antibody responses.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global pandemic. The understanding of the transmission and the duration of viral shedding in SARS-CoV-2 infection is still limited. OBJECTIVES: To assess the timeframe and potential risk of SARS-CoV-2 transmission from hospitalized COVID-19 patients in relation to antibody response. METHOD: We performed a cross-sectional study of 36 COVID-19 patients hospitalized at Karolinska University Hospital. Patients with more than 8 days of symptom duration were sampled from airways, for PCR analysis of SARS-CoV-2 RNA and in vitro culture of replicating virus. Serum SARS-CoV-2-specific immunoglobulin G (IgG) and neutralizing antibodies titers were assessed by immunofluorescence assay (IFA) and microneutralization assay. RESULTS: SARS-CoV-2 RNA was detected in airway samples in 23 patients (symptom duration median 15 days, range 9-53 days), whereas 13 patients were SARS-CoV-2 RNA negative (symptom duration median 21 days, range 10-37 days). Replicating virus was detected in samples from 4 patients at 9-16 days. All but two patients had detectable levels of SARS-CoV-2-specific IgG in serum, and SARS-CoV-2 neutralizing antibodies were detected in 33 out of 36 patients. Total SARS-CoV-2-specific IgG titers and neutralizing antibody titers were positively correlated. High levels of both total IgG and neutralizing antibody titers were observed in patients sampled later after symptom onset and in patients where replicating virus could not be detected. CONCLUSIONS: Our data suggest that the presence of SARS-Cov-2 specific antibodies in serum may indicate a lower risk of shedding infectious SARS-CoV-2 by hospitalized COVID-19 patients.

Long-term outcome after intensive care for COVID-19: differences between men and women-a nationwide cohort study.

BACKGROUND: Questions remain about long-term outcome for COVID-19 patients in general, and differences between men and women in particular given the fact that men seem to suffer a more dramatic course of the disease. We therefore analysed outcome beyond 90 days in ICU patients with COVID-19, with special focus on differences between men and women. METHODS: We identified all patient ≥ 18 years with COVID-19 admitted between March 6 and June 30, 2020, in the Swedish Intensive Care Registry. Patients were followed until death or study end-point October 22, 2020. Association with patient sex and mortality, in addition to clinical variables, was estimated using Cox regression. We also performed a logistic regression model estimating factors associated with 90-day mortality. RESULTS: In total, 2354 patients with COVID-19 were included. Four patients were still in the ICU at study end-point. Median follow-up time was 183 days. Mortality at 90-days was 26.9%, 23.4% in women and 28.2% in men. After 90 days until end of follow-up, only 11 deaths occurred. On multivariable Cox regression analysis, male sex (HR 1.28, 95% CI 1.06-1.54) remained significantly associated with mortality even after adjustments. Additionally, age, COPD/asthma, immune deficiency, malignancy, SAPS3 and admission month were associated with mortality. The logistic regression model of 90-day mortality showed almost identical results. CONCLUSIONS: In this nationwide study of ICU patients with COVID-19, men were at higher risk of poor long-term outcome compared to their female counterparts. The underlying mechanisms for these differences are not fully understood and warrant further studies.

Intraoperative Hypotension and Myocardial Infarction Development Among High-Risk Patients Undergoing Noncardiac Surgery: A Nested Case-Control Study.

BACKGROUND: Hemodynamic instability during anesthesia and surgery is common and associated with cardiac morbidity and mortality. Information is needed regarding optimal blood pressure (BP) threshold in the perioperative period. Therefore, the effect of intraoperative hypotension (IOH) on risk of perioperative myocardial infarction (MI) was explored. METHODS: A nested case-control study with patients developing MI <30 days postsurgery matched with non-MI patients, sampled from a large surgery cohort. Study participants were adults undergoing noncardiac surgery at 3 university hospitals in Sweden, 2007-2014. Matching criteria were age, sex, American Society of Anesthesiologists (ASA) physical status, cardiovascular disease, hospital, year-, type-, and extent of surgery. Medical records were reviewed to validate MI diagnoses and retrieve information on comorbid history, baseline BP, laboratory and intraoperative data. Main exposure was IOH, defined as a decrease in systolic blood pressure (SBP), in mm Hg, from preoperative individual resting baseline lasting at least 5 minutes. Outcomes were acute MI, fulfilling the universal criteria, subclassified as type 1 and 2, occurring within 30 days and mortality beyond 30 days among case and control patients. Conditional logistic regression assessed the association between IOH, decrease in SBP from individual baseline, and perioperative MI. Mortality rates were estimated using Cox proportional hazards. Relative risk estimates are reported as are the corresponding absolute risks derived from the well-characterized source population. RESULTS: A total of 326 cases met the inclusion criteria and were successfully matched with 326 controls. The distribution of MI type was 59 (18%) type 1 and 267 (82%) type 2. Median time to MI diagnosis was 2 days; 75% were detected within a week of surgery. Multivariable analysis acknowledged IOH as an independent risk factor of perioperative MI. IOH, with reduction of 41-50 mm Hg, from individual baseline SBP, was associated with a more than tripled increased odds, odds ratio (OR) = 3.42 (95% confidence interval [CI], 1.13-10.3), and a hypotensive event >50 mm Hg with considerably increased odds in respect to MI risk, OR = 22.6, (95% CI, 7.69-66.2). In patients with a very high-risk burden, the absolute risk of an MI diagnosis increased from 3.6 to 68 per 1000 surgeries. CONCLUSIONS: In patients undergoing noncardiac surgery, IOH is a possible contributor to clinically significant perioperative MI. The high absolute MI risk associated with IOH, among a growing population of patients with a high-risk burden, suggests that increased vigilance of BP control in these patients may be beneficial.

ASA classification and surgical severity grading used to identify a high-risk population, a multicenter prospective cohort study in Swedish tertiary hospitals.

BACKGROUND: Identification of surgical populations at high risk for negative outcomes is needed for clinical and research purposes. We hypothesized that combining two classification systems, ASA (American Society of Anesthesiology physical status) and surgical severity, we could identify a high-risk population before surgery. We aimed to describe postoperative outcomes in a population selected by these two classifications system. METHODS: Data were collected in a Swedish multicentre, time-interrupted prospective, consecutive cohort study. Eligibility criteria were age ≥18 years, ASA ≥3, elective or emergent, major to Xmajor/complex (Specialist Procedure Codes used in United Kingdom), gastrointestinal, urogenital or orthopaedic procedures. Postoperative morbidity was identified by the Postoperative Morbidity Survey on postoperative days 3 ± 1, 7 ± 1, 10 + 5 and graded for severity by the Clavien-Dindo system. Mortality was assessed at 30, 180 and 360 days. RESULTS: Postoperative morbidity was 78/48/47 per cent on postoperative days 3/7/10. Majority of morbidities (67.5 per cent) were graded as >1 by Clavien-Dindo. Any type of postoperative morbidity graded >1 was associated with increased risk for death up to one year. The mortality was 5.7 per cent (61/1063) at 30 days, 13.3 per cent (142/1063) at 6 months and 19.1 per cent (160/1063) at 12 months. CONCLUSION: Severity classification as major to Xmajor/complex and ASA ≥3 could be used to identify a high-risk surgical population concerning postoperative morbidity and mortality before surgery. Combining the two systems future electronic data extraction is possible of a high-risk population in tertiary hospitals.

Predicting peri-operative troponin elevation by advanced electrocardiography.

BACKGROUND: Peri-operative mortality remains a global problem and an improved pre-operative risk assessment identifying those at highest risk for peri-operative myocardial injury might improve postsurgical outcomes. AIMS: To determine whether pre-operative measures of advanced electrocardiography (A-ECG) could predict elevated serum troponin T (TnT) in patients undergoing elective, major non-cardiac surgery. MATERIAL AND METHODS: This observational cohort study included 257 surgical patients who underwent elective major non-cardiac surgery between the years 2012-2013 and 2015-2016 at Karolinska University Hospital. All selected patients were ≥ 18 years of age [median age 70 (63-75) years], had a pre-operative digital 12­lead ECG < 6 months prior to the procedure and a postoperative high-sensitivity cardiac TnT (hs-cTnT) sample. A-ECG confounders including atrial fibrillation or flutter, abundant premature atrial or ventricular contractions, bundle branch blocks, QRS duration >110 ms, heart rate > 100 beats/min and paced rhythms were excluded. Previously validated A-ECG diagnostic scores that detect cardiovascular pathologies were calculated and compared in patients with and without peri-operative myocardial injury, defined as hs-cTnT >14 ng l-1. RESULTS: Pre-operative left ventricular systolic dysfunction by A-ECG was more probable in patients with than without peri-operative myocardial injury (p = 0.03). CONCLUSIONS: While a pre-operative A-ECG score for LVSD was able to differentiate between patients with versus without elevated peri-operative TnT levels, it did not add any further utility to standard clinical parameters for predicting troponin-related events in the studied population.