Large-volume paracentesis effects plasma disappearance rate of indo-cyanine green in critically ill patients with decompensated liver cirrhosis and intraabdominal hypertension

Continuous passive paracentesis versus large-volume paracentesis in the prevention and treatment of intra-abdominal hypertension in the critically ill cirrhotic patient with ascites (COPPTRIAHL): study protocol for a randomized controlled trial

BACKGROUND

Critically ill patients with cirrhosis and ascites are at high risk for intra-abdominal hypertension (IAH) which increases mortality. Clinical guidelines recommend maintaining intra-abdominal pressure (IAP) below 16 mmHg; nonetheless, more than three quarters of critically ill patients with cirrhosis develop IAH during their first week of ICU stay. Standard-of-care intermittent large-volume paracentesis (LVP) relieves abdominal wall tension, reduces IAP, optimizes abdominal perfusion pressure, and is associated with short-term improvement in renal and pulmonary dysfunction. However, there is no evidence of the superiority of different paracentesis strategies in the prevention and treatment of IAH in critically ill patients with cirrhosis. This trial aims to compare the outcomes of continuous passive paracentesis versus LVP in the prevention and treatment of IAH in patients with cirrhosis and ascites.

METHODS

An investigator-initiated, open label, randomized controlled trial, set in a general ICU specialized in liver disease, was initiated in August 2022, with an expected duration of 36 months. Seventy patients with cirrhosis and ascites will be randomly assigned, in a 1:1 ratio, to receive one of two methods of therapeutic paracentesis. A stratified randomization method, with maximum creatinine and IAP values as strata, will homogenize patient baseline characteristics before trial group allocation, within 24 h of admission. In the control group, LVP will be performed intermittently according to clinical practice, with a maximum duration of 8 h, while, in the intervention group, continuous passive paracentesis will drain ascitic fluid for up to 7 days. The primary endpoint is serum creatinine concentration, and secondary endpoints include IAP, measured creatinine clearance, daily urine output, stage 3 acute kidney injury and multiorgan dysfunction assessed at day 7 after enrollment, as well as 28-day mortality rate and renal replacement therapy-free days, and length-of-stay. Prespecified values will be used in case of renal replacement therapy or, beforehand ICU discharge, liver transplant and death. Safety analysis will include paracentesis-related complication rate and harm. Data will be analyzed with an intention-to-treat approach.

DISCUSSION

This is the first trial to compare the impact of different therapeutic paracentesis strategies on organ dysfunction and outcomes in the prevention and treatment of IAH in critically ill patients with cirrhosis and ascites.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04322201 . Registered on 20 December 2019.

Abdominal perfusion pressure in critically ill cirrhotic patients: a prospective observational study

In critical patients, abdominal perfusion pressure (APP) has been shown to correlate with outcome. However, data from cirrhotic patients is scarce. We aimed to characterize APP in critically ill cirrhotic patients, analyze the prevalence and risk factors of abdominal hypoperfusion (AhP) and outcomes. A prospective cohort study in a general ICU specialized in liver disease at a tertiary hospital center recruited consecutive cirrhotic patients between October 2016 and December 2021. The study included 101 patients, with a mean age of 57.2 (± 10.4) years and a female gender proportion of 23.5%. The most frequent etiology of cirrhosis was alcohol (51.0%), and the precipitant event was infection (37.3%). ACLF grade (1-3) distribution was 8.9%, 26.7% and 52.5%, respectively. A total of 1274 measurements presented a mean APP of 63 (± 15) mmHg. Baseline AhP prevalence was 47%, independently associated with paracentesis (aOR 4.81, CI 95% 1.46-15.8, p = 0.01) and ACLF grade (aOR 2.41, CI 95% 1.20-4.85, p = 0.01). Similarly, AhP during the first week (64%) had baseline ACLF grade (aOR 2.09, CI 95% 1.29-3.39, p = 0.003) as a risk factor. Independent risk factors for 28-day mortality were bilirubin (aOR 1.10, CI 95% 1.04-1.16, p < 0.001) and SAPS II score (aOR 1.07, CI 95% 1.03-1.11, p = 0.001). There was a high prevalence of AhP in critical cirrhotic patients. Abdominal hypoperfusion was independently associated with higher ACLF grade and baseline paracentesis. Risk factors for 28-day mortality included clinical severity and total bilirubin. The prevention and treatment of AhP in the high-risk cirrhotic patient is prudential.

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations

OBJECTIVES

To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU.

DESIGN

The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development.

INTERVENTIONS

In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements.

MEASUREMENTS AND MAIN RESULTS

We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence.

CONCLUSIONS

Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

Intra-abdominal hypertension and abdominal compartment syndrome in the critically ill liver cirrhotic patient-prevalence and clinical outcomes. A multicentric retrospective cohort study in intensive care

Background

Liver cirrhosis and ascites are risk factors for intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS); however, data is scarce. We aimed to determine the prevalence of IAH/ACS in a population of critically ill cirrhotic patients with acute medical illness in intensive care and to assess for risk factors and clinical outcomes.

Methods

This was a multicentric retrospective cohort study including two general ICUs and pooled data from a multicentric study between January 2009 and October 2019.

Results

A total of 9,345 patients were screened, and 95 were included in the analysis. Mean age was 56.7±1.3 years, and 79% were male. Liver cirrhosis etiology included alcohol in 45.3% and alcohol plus hepatitis C virus in 9.5%. Precipitating events included infection in 26% and bleeding in 21% of cases. Mean severity score MELD and SAPS II were 26.2±9.9 and 48.5±15.3, respectively, at ICU admission. The prevalence of IAH and ACS was respectively 82.1% and 23.2% with a mean value of maximum IAP of 16.0±5.7 mmHg and IAH grades: absent 17.9%, I 26.3%, II 33.7%, III 17.9%, and IV 4.2%. Independent risk factors for IAH were alcoholic cirrhosis (p = 0.01), West-Haven score (p = 0.01), and PaO2/FiO2 ratio (p = 0.02); as well as infection (p = 0.048) for ACS. Overall, 28-day mortality was 52.6% associated with higher IAP and ACS, and independent risk factors were MELD (p = 0.001), white blood cell count (p = 0.03), PaO2/FiO2 ratio (p = 0.03), and lactate concentration (p = 0.04) at ICU admission.

Conclusions

This study demonstrates a very high prevalence of IAH/ACS in the critically ill cirrhotic patient in intensive care. Increased IAP and ACS were associated with severity of disease and adverse outcomes and independent risk factors for IAH were alcoholic cirrhosis, hepatic encephalopathy and PO2/FiO2 ratio, as well as infection for ACS. Early diagnosis, prevention, and treatment of IAH/ACS might improve outcome in critically ill cirrhotic patients.

Design of Liver Functional Reserve Estimation Technique Based on Optical Densitometry

This work is aimed at creating a modified invasive technique for assessing the liver's functional reserves. A study of the degree of hepatodepression is carried out by measuring the plasma elimination of indocyanine green using the method of optical densitometry. This paper presents test results for an aqueous solution and an albumin solution, as well as the results of measurements of plasma elimination of indocyanine green for patients with liver disease. Perfecting the proposed method will make an important scientific contribution to modern diagnostic medicine. Diagnosing the stages in the progression of the disease and its developing complications can make it possible to rapidly correct the patient's treatment algorithm, achieving positive outcomes in medical practice.

HEP-Net opinion on the management of ascites and its complications in the setting of decompensated cirrhosis in the resource constrained environment of Pakistan

Approximately one half of patients develop ascites within 10 years of diagnosis of compensated cirrhosis. It is a poor prognostic indicator, with only 50% surviving beyond two years. Mortality worsens significantly to 20% to 50% at one year if the ascites becomes refractory to medical therapy. Pakistan has one of the highest prevalence of viral hepatitis in the world and patients with ascites secondary to liver cirrhosis make a major percentage of both inpatient and outpatient burden. Studies indicate that over 80% of patients admitted with ascites have liver cirrhosis as the cause.

This expert opinion suggests proper assessment of patients with ascites in the presence of underlying cirrhosis. This expert opinion includes appropriate diagnosis and management of uncomplicated ascites, refractory ascites and complicated ascites (including spontaneous bacterial peritonitis (SBP) ascites, hepatorenal syndrome (HRS) and hyponatremia. The purpose behind this expert opinion is to help consultants, postgraduate trainees, medical officers and primary care physicians optimally manage their patients with cirrhosis and ascites in a resource constrained setting as is often encountered in a developing country like Pakistan.

Application of the optimized carbon monoxide rebreathing method for the measurement of total haemoglobin mass in chronic liver disease

BACKGROUND

Anemia is common in liver cirrhosis. This generally infers a fall in total hemoglobin mass (tHb-mass). However, hemoglobin concentration ([Hb]) may fall due to an expansion in plasma volume (PV). The "optimized carbon monoxide rebreathing method" (oCOR) measures tHb-mass directly and PV (indirectly using hematocrit). It relies upon carboxyhemoglobin (COHb) distribution throughout the entire circulation. In healthy subjects, such distribution is complete within 6-8 min. Given the altered circulatory dynamics in cirrhosis, we sought in this pilot study, to assess whether this was true in cirrhosis. The primary aim was to ascertain if the standard timings for the oCOR were applicable to patients with chronic liver disease and cirrhosis. The secondary aim was to explore the applicability of standard CO dosing methodologies to this patient population.

METHODS

Sixteen patients with chronic liver parenchymal disease were studied. However, tHb-mass was determined using the standard oCOR technique before elective paracentesis. Three subjects had an inadequate COHb% rise. In the remaining 13 (11 male), mean ± standard deviation (SD) age was 52 ± 13.8 years, body mass 79.1 ± 11.4 kg, height 175 ± 6.8 cm. To these, mean ± SD dose of carbon monoxide (CO) gas administered was 0.73 ± 0.13 ml/kg COHb values at baseline, 6 and 8 min (and "7-min value") were compared to those at 10, 12, 15 and 20 min after CO rebreathing.

RESULTS

The "7-min value" for median COHb% (IQR) of 6.30% (6.21%-7.47%) did not differ significantly from those at subsequent time points (8 min: 6.30% (6.21%-7.47%), 10 min: 6.33% (6.00%-7.50%), 12 min: 6.33% (5.90%-7.40%), 15 min: 6.37% (5.80%-7.33%), 20 min: 6.27% (5.70%-7.20%)). Mean difference in calculated tHb-mass between minute 7 and minute 20 was only 4.1 g, or 0.6%, p = .68. No subjects reported any adverse effects.

CONCLUSIONS

The oCOR method can be safely used to measure tHb-mass in patients with chronic liver disease and ascites, without adjustment of blood sample timings. Further work might refine and validate appropriate dosing regimens.

Plasma Disappearance Rate of Indocyanine Green for Determination of Liver Function in Three Different Models of Shock

The measurement of the liver function via the plasma disappearance rate of indocyanine green (PDR_ICG) is a sensitive bed-side tool in critical care. Yet, recent evidence has questioned the value of this method for hyperdynamic conditions. To evaluate this technique in different hemodynamic settings, we analyzed the PDR_ICG and corresponding pharmacokinetic models after endotoxemia or hemorrhagic shock in rats. Male anesthetized Sprague-Dawley rats underwent hemorrhage (mean arterial pressure 35 ± 5 mmHg, 90 min) and 2 h of reperfusion, or lipopolysaccharide (LPS) induced moderate or severe (1.0 vs. 10 mg/kg) endotoxemia for 6 h (each n = 6). Afterwards, PDR_ICG was measured, and pharmacokinetic models were analyzed using nonlinear mixed effects modeling (NONMEM^®). Hemorrhagic shock resulted in a significant decrease of PDR_ICG, compared with sham controls, and a corresponding attenuation of the calculated ICG clearance in 1- and 2-compartment models, with the same log-likelihood. The induction of severe, but not moderate endotoxemia, led to a significant reduction of PDR_ICG. The calculated ICG blood clearance was reduced in 1-compartment models for both septic conditions. 2-compartment models performed with a significantly better log likelihood, and the calculated clearance of ICG did not correspond well with PDR_ICG in both LPS groups. 3-compartment models did not improve the log likelihood in any experiment. These results demonstrate that PDR_ICG correlates well with ICG clearance in 1- and 2-compartment models after hemorrhage. In endotoxemia, best described by a 2-compartment model, PDR_ICG may not truly reflect the ICG clearance.