Intensive Care Management of Patients with Cirrhosis

Purpose of review

Cirrhosis is a major worldwide health problem which results in a high level of morbidity and mortality. Patients with cirrhosis who require intensive care support have high mortality rates of near 50%. The goal of this review is to address the management of common complications of cirrhosis in the ICU.

Recent findings

Recent epidemiological studies have shown an increase in hospitalizations due to advanced liver disease with an associated increase in intensive care utilization. Given an increasing burden on the healthcare system, it is imperative that we strive to improve our management cirrhotic patients in the intensive care unit.

Summary

Large studies evaluating the management of patients in the intensive care setting are lacking. To date, most recommendations are based on extrapolation of data from studies in cirrhosis outside of the ICU or by applying general critical care principles which may or may not be appropriate for the critically ill cirrhotic patient. Future research is required to answer important management questions.

     

Alcohol as a Factor in 911 Calls in Denver

Background: Excessive alcohol consumption is associated with a substantial number of emergency department visits annually and is responsible for a significant number of lives lost each year in the United States. However, a minimal amount is known about the impact of alcohol on the EMS system. Objectives: The primary objective was to determine the proportion of 9-1-1 calls in Denver, Colorado in which (1) alcohol was a contributing factor or (2) the individual receiving EMS services had recently ingested alcohol. The secondary objectives were to compare the characteristics of EMS calls and to estimate the associated costs. Methods: This was a prospective observational cohort study of EMS calls for adults from July 1, 2012, to June 30, 2014. Primary outcomes for the study were alcohol as a contributing factor to the EMS call and recent alcohol consumption by the patient receiving EMS services. Logistic regression was utilized to determine the associations between EMS call characteristics and the outcomes. Cost was estimated using historic data. Results: During the study period, 169,642 EMS calls were completed by the Denver Health Paramedic Division. Of these 71% were medical and 29% were trauma-related. The median age was 45 (interquartile range [IQR] 29–59) years, and 55% were male. 50,383 calls (30%) had alcohol consumption, and 49,165 (29%) had alcohol as a contributing factor. Alcohol related calls were associated with male sex, traumatic injuries including head trauma, emergent response, use of airway adjuncts, cardiac monitoring, glucose measurement, use of restraints, use of spinal precautions, and administration of medications for sedation. Estimated costs to the EMS system due to alcohol intoxication exceeded $14 million dollars over the study period and required in excess of 37 thousand hours of paramedic time. Conclusions: Compared to 9-1-1 calls that do not involve alcohol, alcohol-related calls are more likely to involve male patients, emergent response, traumatic injuries, advanced monitoring, airway adjuncts, and medications for sedation. This represents a significant burden on the emergency system and society. Further studies are needed to evaluate whether additional interventions such as social services could be used to lessen this burden.     

Computer simulated modeling of healthy and diseased right ventricular and pulmonary circulation

We have previously developed a simulated cardiovascular physiology model for in-silico testing and validation of novel closed-loop controllers. To date, a detailed model of the right heart and pulmonary circulation was not needed, as previous controllers were not intended for use in patients with cardiac or pulmonary pathology. With new development of controllers for vasopressors, and looking forward, for combined vasopressor-fluid controllers, modeling of right-sided and pulmonary pathology is now relevant to further in-silico validation, so we aimed to expand our existing simulation platform to include these elements. Our hypothesis was that the completed platform could be tuned and stabilized such that the distributions of a randomized sample of simulated patients’ baseline characteristics would be similar to reported population values. Our secondary outcomes were to further test the system in representing acute right heart failure and pulmonary artery hypertension. After development and tuning of the right-sided circulation, the model was validated against clinical data from multiple previously published articles. The model was considered ‘tuned’ when 100% of generated randomized patients converged to stability (steady, physiologically-plausible compartmental volumes, flows, and pressures) and ‘valid’ when the means for the model data in each health condition were contained within the standard deviations for the published data for the condition. A fully described right heart and pulmonary circulation model including non-linear pressure/volume relationships and pressure dependent flows was created over a 6-month span. The model was successfully tuned such that 100% of simulated patients converged into a steady state within 30 s. Simulation results in the healthy state for central venous volume (3350?±?132 ml) pulmonary blood volume (405?±?39 ml), pulmonary artery pressures (systolic 20.8?±?4.1 mmHg and diastolic 9.4?±?1.8 mmHg), left atrial pressure (4.6?±?0.8 mmHg), PVR (1.0?±?0.2 wood units), and CI (3.8?±?0.5 l/min/m²) all met criteria for acceptance of the model, though the standard deviations of LAP and CI were somewhat narrower than published comparators. The simulation results for right ventricular infarction also fell within the published ranges: pulmonary blood volume (727?±?102 ml), pulmonary arterial pressures (30?±?4 mmHg systolic, 12?±?2 mmHg diastolic), left atrial pressure (13?±?2 mmHg), PVR (1.6?±?0.3 wood units), and CI (2.0?±?0.4 l/min/m²) all fell within one standard deviation of the reported population values and vice-versa. In the pulmonary hypertension model, pulmonary blood volume of 615?±?90 ml, pulmonary arterial pressures of 80?±?14 mmHg systolic, 36?±?7 mmHg diastolic, and the left atrial pressure of 11?±?2 mmHg all met criteria for acceptance. For CI, the simulated value of 2.8?±?0.4 l/min/m² once again had a narrower spread than most of the published data, but fell inside of the SD of all published data, and the PVR value of 7.5?±?1.6 wood units fell in the middle of the four published studies. The right-ventricular and pulmonary circulation simulation appears to be a reasonable approximation of the right-sided circulation for healthy physiology as well as the pathologic conditions tested.     

Gene × Environment Interactions in the Development of Preschool Effortful Control,and Its Implications for Childhood Externalizing Behavior

This study examined the role of gene × environment interaction (G × E) in the development of effortful control (EC) and externalizing symptoms (EXT). Participants included 361 adopted children, and their Adoptive Parents (APs) and Birth Mothers (BMs), drawn from the Early Growth and Development Study. The primary adoptive caregivers’ (AP1) laxness and overreactivity were assessed when children were 27-months-old, and used as indices of environmental influences on EC. Heritable influences on child EC were assessed by the BMs’ personality characteristics (emotion dysregulation, agreeableness). Secondary adoptive caregivers (AP2) reported on children’s EC at 54 months, and EXT at 7 years. Interactions between BM characteristics and AP1 laxness were related to EC and indirectly predicted EXT via EC. Parental laxness and EC were positively associated if children had high heritable risk for poor EC (BM high emotion dysregulation or low agreeableness), but negatively associated if children had low heritable risk for poor EC (BM low emotion dysregulation or high agreeableness). BM agreeableness also moderated associations between AP1 overreactivity and effortful control, and yielded a similar pattern of results. Our findings suggest that G × E is an important first step in the development of EXT via its effect on EC. Consistent with “goodness of fit” models, heritable tendencies can affect which parenting practices best support EC development.

     

Prevalence and clinical features of patients with concurrent HBsAg and anti‐HBs: Evaluation of the hepatitis B research network cohort

The prevalence of concurrent HBsAg and anti‐HBs in plasma of persons with chronic hepatitis B virus (HBV) infection is variable and its clinical significance enigmatic. We examined the prevalence and clinical and virological features of concurrent HBsAg and anti‐HBs in children and adults with chronic HBV infection living in North America. A total of 1462 HBsAg positive participants in the Hepatitis B Research Network paediatric and adult cohorts were included (median age 41 (range 4‐80) years, 48% female, 11% white, 13% black, 73% Asians). Only 18 (1.2%) were found to be anti‐HBs positive (≥10 mIU/mL) at initial study evaluation. Distributions of sex, race, HBV genotype and ALT were similar between participants with and without concurrent anti‐HBs. Those who were anti‐HBs positive appeared to be older (median age 50 vs 41 years, P = .06), have lower platelet counts (median 197 vs 222 × 103/mm³, P = .07) and have higher prevalence of HBeAg (44% vs 26%, P = .10). They also had lower HBsAg levels (median 2.0 vs 3.5 log₁₀ IU/mL, P = .02). Testing of follow‐up samples after a median of 4 years (range 1‐6) in 12 of the 18 participants with initial concurrent anti‐HBs showed anti‐HBs became undetectable in 6, decreased to <10 mIU/mL in 1 and remained positive in 5 participants. Two patients lost HBsAg during follow‐up. In conclusion, prevalence of concurrent HBsAg and anti‐HBs was low at 1.2%, with anti‐HBs disappearing in some during follow‐up, in this large cohort of racially diverse children and adults with chronic HBV infection living in North America. Presence of concurrent HBsAg and anti‐HBs did not identify a specific phenotype of chronic hepatitis B, nor did it appear to affect clinical outcomes.     

Utility of snout wipe samples for influenza A virus surveillance in exhibition swine populations

Background

Sporadic influenza A virus (IAV) outbreaks in humans and swine have resulted from commingling of large numbers of people and pigs at agricultural fairs in the United States. Current antemortem IAV surveillance strategies in swine require collecting nasal swabs, which entails restraining pigs with snares. Restraint is labor-intensive for samplers, stressful for pigs, and displeasing to onlookers because pigs often resist and vocalize.

Objective

To evaluate the utility of snout wipes in exhibition swine as a method to make IAV surveillance efforts less intrusive, less labor-intensive, and more widely accepted among pig owners and exhibition officials.

Methods

Three materials (rayon/polyester gauze, cotton gauze, and Swiffer® Sweeper dry cloths) were inoculated with IAV, and viral recoveries from these materials were quantified using qRT-PCR and TCID₅₀ assays. In a field trial, paired cotton gauze snout wipes and gold standard polyester-tipped nasal swabs were collected from 553 pigs representing 29 agricultural fairs and the qualitative results of rRT-PCR and viral isolation were compared.

Results and Conclusions

Viral recoveries from potential snout wipe materials ranged from 0·26 to 1·59 log₁₀ TCID₅₀/ml less than that of the positive control in which no substrate was included; rayon/polyester gauze performed significantly worse than the other materials. In the field, snout wipes and nasal swabs had high levels of agreement for both rRT-PCR detection and virus isolation. Although further investigation and refinement of the sampling method is needed, results indicate that snout wipes will facilitate convenient and undisruptive IAV surveillance in pigs at agricultural fairs.     

Acute-on-Chronic Liver Failure: What are the Implications?

Acute-on-chronic liver failure (ACLF) is a clinical entity that is well recognized by those who care for patients with cirrhosis, however in spite of this widespread recognition, there remains little consensus with regard to definition and clinical features. While many similarities exist between ACLF and decompensated cirrhosis, there are also key differences, the implications of which are far reaching for both clinicians and patients alike. Among these differences are the possibility of a reversible component, the presence of a defined insult, prognosis, and outcomes associated with ACLF (see Fig. 1). However, for ACLF to have meaningful clinical implications, it first must be defined. If ACLF can be clearly defined and more easily recognized, then clinicians may be better able to prevent, treat, prognosticate, and counsel such patients.