Clinical Effects of a Longer Duration of Polymyxin B-Immobilized Fiber Column Direct Hemoperfusion Therapy for Severe Sepsis and Septic Shock

Effects of Early Initiation of Polymyxin B Hemoperfusion Therapy in Patients with Cancer with Refractory Septic Shock

Background: We aimed to analyze the correlation between in-hospital mortality and hemodynamic changes, using polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) initiation time in patients with cancer with refractory septic shock. Methods: Forty-six patients with cancer who received PMX-DHP for refractory septic shock were retrospectively analyzed and classified into early (≤3 h between refractory septic shock and PMX-DHP; n = 17) and late (>3 h; n = 29) initiation groups. The vasopressor inotropic score (VIS), sequential organ failure assessment (SOFA) score, and lactate clearance before and 24 h post-PMX-DHP were compared. Results: Overall, 52.17% died from multiple organ dysfunction, with a lower mortality rate in the early initiation group. The VIS and SOFA score decreased in both groups, but the magnitude of decrease was not significant. Lactate clearance improved in both groups, with greater improvement in the early initiation group. Univariable analysis identified associations of in-hospital mortality with early initiation, ΔC-reactive protein, lactate clearance, ΔSOFA score, and ΔVIS. Multivariable analysis demonstrated associations of in-hospital mortality risk with ΔSOFA score and early PMX-DHP initiation. Overall survival was higher in the early initiation group. Early initiation of PMX-DHP in patients with cancer with refractory septic shock reduced in-hospital mortality and improved lactate clearance.

Clinical outcome of intraoperative hemodialysis using a hemoconcentrator during cardiopulmonary bypass for dialysis-dependent patients

OBJECTIVES

The basic materials and structure of a hemoconcentrator incorporated into cardiopulmonary bypass (CPB) circuits are similar to those of hemodialyzers. Gravity drainage hemodiafiltration (GHDF) is an easy-to-use intraoperative renal replacement therapy (RRT) that utilizes a hemoconcentrator. This study aimed to verify whether GHDF can correct electrolyte imbalance and remove uremic toxins in dialysis-dependent patients and to evaluate the clinical outcomes of GHDF by comparing it with a conventional method of dilutional ultrafiltration (DUF).

METHODS

This study retrospectively compared perioperative clinical values of 41 dialysis-dependent patients (21 patients with GHDF and 20 patients with DUF) who underwent open-heart surgery. Changes in serum parameters before and after passing through the hemoconcentrator were also compared.

RESULTS

Compared to DUF, GHDF significantly lowered potassium, blood urea nitrogen, and creatinine levels at the outflow of the hemoconcentrator. Less catecholamine was needed to wean CPB in GHDF than in DUF. The P/F ratio (arterial blood oxygen pressure/inhaled oxygen concentration) at the end of surgery was significantly higher in GHDF than in DUF (450.8 ± 149.7 vs. 279.3 ± 153.5; p < 0.001). Postoperative intubation time was shorter in GHDF than in DUF (8.3 ± 5.9 vs. 18.7 ± 16.1 h; p = 0.006). The major morbidity and mortality rates were comparable in both groups.

CONCLUSIONS

GHDF removed both potassium and uremic toxins more efficiently than DUF in dialysis-dependent patients. Less catecholamine was needed to wean CPB using GHDF. It improved the immediate postoperative respiratory function and enabled earlier extubation. GHDF is a novel and effective option for intraoperative RRT in dialysis-dependent patients undergoing open-heart surgery.

Japanese national survey on declined liver allografts from brain-dead donors: High decline rate but promising outcomes in allografts with moderate steatosis

Aim

Liver allografts from brain-dead donors, which were declined and were eventually not transplanted due to accompanying marginal factors, have never been surveyed in Japan. We surveyed the declined allografts and discussed the graft potential focusing on various marginal factors.

Methods

We collected data on brain-dead donors between 1999 and 2019 from the Japan Organ Transplant Network. We divided their liver allografts into declined (nontransplanted) and transplanted ones, and then characterized declined ones focusing on their timepoints of decline and accompanying marginal factors. For each marginal factor, we calculated the decline rate from the number of declined and transplanted allografts, and assessed the 1-year graft survival rate from transplanted allografts.

Results

A total of 571 liver allografts were divided into 84 (14.7%) declined and 487 (85.3%) transplanted ones. In the declined allografts, a majority was declined after laparotomy (n = 55, 65.5%), most of which had steatosis and/or fibrosis (n = 52). Out of the moderate steatotic (without F ≥ 2 fibrosis) allografts (n = 33), 21 were declined and 12 were transplanted, leading to a 63.6% decline rate. The latter 12 achieved a 92.9% 1-year graft survival rate after transplantation. Comparison of donor background showed no significant difference between the declined and transplanted allografts.

Conclusion

Pathological abnormalities of steatosis/fibrosis seem to be the most common donor factor leading to graft decline in Japan. Allografts with moderate steatosis were highly declined; however, transplanted ones achieved promising outcomes. This national survey highlights the potential utility of liver allografts with moderate steatosis.

Modifications of peripheral perfusion in patients with vasopressor-dependent septic shock treated with polymyxin B-direct hemoperfusion

Abnormal peripheral perfusion (PP) worsens the prognosis of patients with septic shock. Polymyxin B-direct hemoperfusion (PMX-DHP) increases blood pressure and reduces vasopressor doses. However, the modification of PP following administration of PMX-DHP in patients with vasopressor-dependent septic shock have not yet been elucidated. A retrospective exploratory observational study was conducted in patients with septic shock treated with PMX-DHP. Pulse-amplitude index (PAI), vasoactive inotropic score (VIS), and cumulative fluid balance data were extracted at PMX-DHP initiation (T0) and after 24 (T24) and 48 (T48) h. Changes in these data were analyzed in all patients and two subgroups (abnormal PP [PAI < 1] and normal PP [PAI ≥ 1]) based on the PAI at PMX-DHP initiation. Overall, 122 patients (abnormal PP group, n = 67; normal PP group, n = 55) were evaluated. Overall and in the abnormal PP group, PAI increased significantly at T24 and T48 compared with that at T0, with a significant decrease in VIS. Cumulative 24-h fluid balance after PMX-DHP initiation was significantly higher in the abnormal PP group. PMX-DHP may be an effective intervention to improve PP in patients with abnormal PP; however, caution should be exercised as fluid requirements may differ from that of patients with normal PP.

Development of a risk score model for 1‐year graft loss after adult deceased donor liver transplantation in Japan based on a 20‐year nationwide cohort

Aim

Using nationwide data collected over the past 20 years, we aimed to investigate deceased donor liver transplantation (DDLT) outcomes to develop a unique risk model that can be used to establish a standard for organ acceptance in Japan.

Methods

Data were collected for 449 recipients aged ≥18 years who underwent DDLT between 1999 and 2019. Least absolute shrinkage and selection operator (LASSO) regression analysis was utilized to develop an original risk score model for 1‐year graft loss (termed the Japan Risk Index [JRI]). We developed risk indices according to recipient, donor, and surgery components (termed JRI‐R, D, and S, respectively). The JRI was validated via a 5‐fold cross‐validation. We also compared DDLT outcomes and risk indices among Era1 (−2011), Era2 (−2015), and Era3 (−2019).

Results

The 1‐year graft survival rate was 89.5% and improved significantly, reaching 84.7%, 87.6%, and 93.9% in Era1, Era2, and Era3, respectively. The JRI was calculated as JRI‐R (re‐transplantation, Model for End‐Stage Liver Disease score, medical condition in intensive care unit) × JRI‐D (age, catecholamine index, maximum sodium, maximum total bilirubin) × JRI‐S (total ischemic time) × 0.84. The risk model achieved a mean C‐statistic value of 0.81 in the validation analysis. The risk index was significantly lower in Era3 than in Era2.

Conclusion

Changes in the risk index over time indicated that avoiding risks contributed to the improved outcomes in Era3. The JRI is unique to adult DDLT in Japan and may be useful as a reference for organ acceptance in the future.

The Rationale and Current Status of Endotoxin Adsorption in the Treatment of Septic Shock

Lipopolysaccharide, the main component of the outer membrane of Gram-negative bacteria is a highly potent endotoxin responsible for organ dysfunction in sepsis. It is present in the blood stream not only in Gram-negative infections, but also in Gram-positive and fungal infections, presumably due to sepsis-related disruption of the intestinal barrier. Various pathways, both extra- and intracellular, are involved in sensing endotoxin and non-canonical activation of caspase-mediated pyroptosis is considered to have a major role in sepsis pathophysiology. Endotoxin induces specific pathological alterations in several organs, which contributes to poor outcomes. The adverse consequences of endotoxin in the circulation support the use of anti-endotoxin therapies, yet more than 30 years of experience with endotoxin adsorption therapies have not provided clear evidence in favor of this treatment modality. The results of small studies support timely endotoxin removal guided by measuring the levels of endotoxin; unfortunately, this has not been proven in large, randomized studies. The presence of endotoxemia can be demonstrated in the majority of patients with COVID-19, yet only case reports and case series describing the effects of endotoxin removal in these patients have been published to date. The place of blood purification therapies in the treatment of septic shock has not yet been determined.

Vasopressin Loading for Refractory Septic Shock: A Preliminary Analysis of a Case Series

Background: Vasopressin is one of the strong vasopressor agents associated with ischemic events. Responses to the administration of vasopressin differ among patients with septic shock. Although the administration of a high dose of vasopressin needs to be avoided, the effects of bolus loading have not yet been examined. Since the half-life of vasopressin is longer than that of catecholamines, we hypothesized that vasopressin loading may be effective for predicting responses to its continuous administration. Methods: We retrospectively analyzed consecutive cases of septic shock for which vasopressin was introduced with loading under noradrenaline at >0.2 μg/kg/min during the study period. Vasopressin was administered in a 1 U bolus followed by its continuous administration at 1 U/h. The proportion of patients with a negative catecholamine index (CAI) change 6 h after the introduction of vasopressin was set as the primary outcome. We defined non-responders for exploration as those with a mean arterial pressure change <18 mmHg 1 min after vasopressin loading, among whom none had a change in CAI <0. Results: Twenty-one consecutive cases were examined in the present study, and included 14 responders and 7 non-responders. The primary outcome accounted for 71.4% of responders and 0% of non-responders, with a significant difference (p = 0.0039). Median CAI changes 2, 4, and 6 h after the administration of vasopressin were 0, -5, and -10 in responders and +20, +10, and +10 in non-responders, respectively. CAI was not reduced in any non-responder. Outcomes including mortality were not significantly different between responders and non-responders. Digital ischemia (1/21) and mesenteric ischemia (1/21) were observed. Conclusions: Vasopressin loading may predict responses to its continuous administration in septic shock patients. Further investigations involving a safety analysis are needed.

Impact of Extended Duration of Polymyxin B-Immobilized Fiber Column Direct Hemoperfusion on Hemodynamics, Vasoactive Substance Requirement, and Pulmonary Oxygenation in Patients with Sepsis: An Observational Study

INTRODUCTION

Polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) is used for patients with septic shock, and the recommended hemoperfusion period is 2 h. However, it remains unclear whether the optimal duration is 2 h or longer. The purpose of this study was to compare the effects of PMX-DHP between conventional and longer duration of PMX-DHP.

METHODS

We retrospectively investigated 103 patients with sepsis who underwent PMX-DHP. The demographic data, routine biochemistry, microbiological data, and primary infection site were reviewed in the medical chart. The acute physiology and chronic health evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score, heart rate, mean arterial pressure (MAP), vasoactive-inotropic score (VIS), and PaO2/FiO2, at baseline and day 3, were compared between the standard group (2 h of PMX-DHP) and the extended group (>2 h of PMX-DHP).

RESULTS

Median MAP was significantly lower and median VIS was significantly higher in the extended group at baseline (p < 0.05, 0.01, respectively) There were no significant differences in APACHE II score, SOFA score, and PaO2/FiO2 at baseline between the 2 groups. The increase of MAP and the decrease in VIS from baseline to day 3 were significantly greater in the extended group (p < 0.01, respectively). In the extended group, increase in PaO2/FiO2 was significantly larger in the patients who underwent ≥8 h duration than that in patients who underwent <8 h duration (p < 0.01). The ventilator-free days, the incidence of continuous renal replacement therapy, and the 28-day mortality were not different between the groups.

DISCUSSION/CONCLUSIONS

Longer duration of PMX-DHP was associated with the improved MAP and decreased volume of vasoactive-inotropic agents compared with the conventional duration. Eight and longer hours duration of PMX-DHP was associated with the improvement in the pulmonary oxygenation. Further studies are needed to confirm the efficacy of longer duration of PMX-DHP in patients with septic shock.

Up-to-date information on polymyxin B-immobilized fiber column direct hemoperfusion for septic shock

Endotoxin adsorption therapy by polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) has been used for the treatment of septic shock patients. Endotoxin, an outer membrane component of Gram-negative bacteria, plays an important role in the pathogenesis of septic shock. Endotoxin triggers a signaling cascade for leukocytes, macrophage, and endothelial cells to secrete various mediators including cytokines and nitric oxide, leading to septic shock and multiple organ dysfunction syndrome. PMX-DHP directly adsorbed not only endotoxin but also monocytes and anandamide. It reduced blood levels of inflammatory cytokines such as interleukin (IL)-1, IL-6, tumor necrosis factor-alpha and IL-17A, adhesion molecules, plasminogen activator inhibitor 1, and high mobility group box-1. As a result, PMX-DHP increased blood pressure and reduced the dose of vasoactive-inotropic agents. PMX-DHP improved monocyte human leukocyte antigen-DR expression in patients with severe sepsis and septic shock. A post hoc analysis of EUPHRATES (Evaluating the Use of Polymyxin B Hemoperfusion in Randomized Controlled Trial of Adults Treated for Endotoxemia and Septic Shock) trial has shown that PMX-DHP significantly reduced 28-day mortality compared with the control group in septic shock patients with endotoxin activity assay level between 0.60 and 0.89. Longer duration of PMX-DHP may be another strategy to bring out the beneficial effects of PMX-DHP. Further studies are needed to confirm the efficacy of PMX-DHP treatment for septic shock.

Lactate predicts the 28-day survival rate in patients with septic shock treated with the combination of PMX-DHP and rTM

We have previously reported that combination therapy with polymyxin-B direct hemoperfusion (PMX-DHP) and recombinant thrombomodulin (rTM) is effective in patients with septic shock accompanied by disseminated intravascular coagulation (DIC). Two previous studies reporting the favorable effect of early initiation of PMX-DHP for septic shock did not focus on the combination therapy of PMX-DHP and rTM. This retrospective study included 47 consecutive patients who underwent the combination therapy of PMX-DHP and rTM for septic shock with DIC from August 2011 to August 2016. Main exposure was early or late initiation of PMX-DHP. PMX-DHP initiated within 12 hours after catecholamine administration was designated as early group (N = 25) and later than 12 hours as late group (N = 22). Main outcome was 28-day survival rate. The patient characteristics were age median 73 (IQR 68-78) years, 26 men (55%), APACHE II score 32.7 ± 7.7 and lactate 26.0 (18.0-41.0) mg/dL. The 28-day survival rate after PMX-DHP initiation was 76.6% and was not significantly different in the two groups. In the early group, APACHE II score was lower (P = .02), and lactate was higher (P = .005) than in the late group. Lactate was the only predictor of 28-day mortality [odds ratio (95%CI) per 1 mg/dL, 1.08 (1.03-1.19); P = .037] in multivariate logistic regression analysis adjusted with age, sex, APACHE II score, lactate and timing of PMX-DHP initiation. Late PMX-DHP initiation did not lead to statistically worse 28-day survival rate in this combination therapy. The combination therapy of PMX-DHP and rTM may improve the therapeutic effect of PMX-DHP and modify the effect of early PMX-DHP on the prognosis. Lactate may be an appropriate indicator rather than time after catecholamine administration if we discuss when to start PMX-DHP in this combination therapy.

Clinical effects of polymyxin B-immobilized fiber column direct hemoperfusion for severe bacterial meningitis: A series of 10 cases

Our results suggest a possible role for Polymyxin B-immobilized fiber column direct hemoperfusion in combination with standard therapy in the rapid improvement of impaired consciousness in patients with severe bacterial meningitis.

Anti-endotoxin Properties of Polymyxin B-immobilized Fibers

Polymyxin B is an antibiotic that shows strong bactericidal activity against Gram-negative bacteria, by binding to and inactivating endotoxin. Systemic administration of polymyxin B in humans is restricted because of its nephrotoxicity and neurotoxicity, and this compound was therefore considered a strong candidate ligand for the extracorporeal selective adsorption of circulating endotoxin in the blood. Toraymyxin® is a direct hemoperfusion column that uses polymyxin B attached to an insoluble carrier to bind endotoxin in the blood. In 1994, the Japanese National Health Insurance system approved the use of Toraymyxin for the treatment of endotoxemia and septic shock.In this chapter, we will review the development, clinical use, and efficacy of Toraymyxin, examine the structure of the Toraymyxin column, and comment on the current position of Toraymyxin in the treatment of severe sepsis and septic shock. We will also highlight some potential new applications of Toraymyxin for pulmonary diseases.

"Impact of timing of polymyxin B-immobilized fiber column direct hemoperfusion on outcome in patients with septic shock: a single-center observational study"

Aim

The effect of polymyxin B-immobilized fiber column direct hemoperfusion (PMX-DHP) is controversial. The present study investigates whether outcome in septic shock patients is affected by the time until PMX-DHP initiation and the location of the infection site (intra- or extra-abdominal infection (IAI/EAI)].

Methods

This retrospective observational study included patients receiving PMX-DHP for septic shock but excluded those treated after cardiac surgery or cardiac arrest. Based on the median and/or quartile time from catecholamine treatment to PMX-DHP initiation, the patient cohort was divided into four groups and the IAI and EAI groups into two subgroups.

Results

Among the 49 eligible patients, overall 90-day mortality in group 1 (PMX-DHP within 6 h) at 8.3% was significantly lower than in groups 2 (6-9 h; 46.1%), 3 (9-29 h; 58.3%) and 4 (>29 h; 75.0%) (P = 0.021). Multivariate logistic regression analysis showed that the duration from catecholamine treatment to PMX-DHP initiation correlated with 90-day mortality (odds ratio 1.060; 95% confidence interval, 1.004-1.117; P = 0.028). Among the 29 IAI patients, 90-day mortality was significantly lower in the early (within 9 h) than the late group (>9 h) (13.3% versus 64.2%; P = 0.003), but no significant intergroup difference was noted among the 20 EAI patients.

Conclusion

Our results suggest that early PMX-DHP initiation (within 9 h after catecholamine treatment) reduces mortality from septic shock, especially in IAI patients.

Association between lymphocyte count and neurological outcomes in post-cardiac arrest patients treated with mild therapeutic hypothermia

Aim

To examine lymphocyte counts as a predictive prognostic marker in patients with coma after cardiac arrest.

Methods

We retrospectively evaluated patients with coma after cardiac arrest admitted to the intensive care unit of Shiga University of Medical Science (Otsu, Japan). Lymphocyte counts were measured for 6 days from admission. Neurological outcome was assessed as favorable or unfavorable using cerebral performance categories. Associations between lymphocyte count and prognosis were investigated using multivariate logistic regression analysis and receiver operating characteristic curves.

Results

Forty‐six patients were assessed from February 2012 to December 2016. Survivors had significantly higher lymphocyte counts than non‐survivors on days 2 and 5. Multivariate analysis showed that lymphocyte count was not associated with 90‐day mortality. Patients with favorable neurological outcome at discharge had significantly higher lymphocyte counts on days 2–6 than patients with unfavorable outcomes. Multivariate logistic regression analysis, including possible confounders, showed that lymphocyte counts on days 2–4 and 6 were associated with neurological outcome (day 2: odds ratio [OR] = 0.75, 95% confidence interval [CI] = 0.58–0.97, P = 0.029; day 3: OR = 0.68, 95% CI = 0.47–0.98, P = 0.04; day 4: OR = 0.4, 95% CI = 0.16–1.00, P = 0.05; day 6: OR = 0.69, 95% CI = 0.48–0.99, P = 0.046). Receiver operating characteristic curve analysis indicated high accuracy for predicting neurological outcome for each lymphocyte count on days 2–6 using the area under the curve, day 4 values being most accurate (day 2: 0.776, day 3: 0.787, day 4: 0.909, day 5: 0.774, day 6: 0.839).

Conclusion

Lymphocyte counts on days 2–4 and 6 after cardiac arrest are associated with neurological outcome; counts on day 4 most accurately predict neurological outcome.

In Vitro Study of Endotoxin Adsorption by a Polymyxin B-Immobilized Fiber Column

BACKGROUND

Polymyxin B-immobilized fiber (PMX-F) columns are used as therapeutic interventions for septic shock. The clinical efficacy has been reported for 2-h applications, but their ability to adsorb endotoxin over longer treatments has not been fully elucidated. We hypothesized that PMX-F columns are capable of endotoxin removal for more than 2 h.

METHOD

We designed closed circuits incorporating either a PMX-F column with an 8.5-mL priming volume (PMX-01R) or a sham-control column, and used inactivated fetal bovine serum as the circulating perfusate. Endotoxin was continuously injected at a fixed rate for 24 h, and perfusate endotoxin concentrations were measured at fixed time points. PMX-01R endotoxin adsorption was calculated from the difference in the endotoxin concentrations.

RESULTS

PMX-01R endotoxin adsorption increased continuously in a virtually linear manner.

CONCLUSIONS

The PMX-01R column showed sustained endotoxin adsorption for at least 24 h. This indicated that PMX-F columns would be capable of clinical endotoxin removal for 24 h.

Experimental and Clinical Evaluation of Predilution and Postdilution Continuous Venovenous Hemofiltration on Clearance Characteristics

We compared the clearance characteristics of low-to-high molecular weight substances during pre-and postdilution continuous venovenous hemofiltration (CVVH) in experimental and clinical conditions. Experimental circuits for pre- and postdilution CVVH were prepared using a test solution containing creatinine (110 Da), inulin (5,000 Da), interleukin (IL)-8 (8,000 Da), IL-6 (22,000 Da), and tumor necrosis factor (TNF)-α (51,000 Da). Quantity of test solution flow and filtration flow (QF) were set to 150 ml/min and 10, 20, and 35 ml/min, respectively. Clinical CVVH settings were blood flow (QB): 150 ml/min and QF: 35 ml/min. Samples were obtained from pre- and posthemofilters, and clearance of target substances was determined during pre- and postdilution CVVH in experimental and clinical conditions. Clearance changed according to QF during both pre- and postdilution CVVH in the experiment. Clearance of creatinine, inulin (experiment only), and IL-8 during postdilution CVVH was superior to that during predilution CVVH. Few differences were seen in clearance of IL-6 and TNF-α between dilution methods in the experiment and clinical practice. Clearance of IL-8 and IL-6 decreased during postdilution CVVH over 24 hr but did not change during predilution CVVH in clinical practice. Predilution CVVH is useful for stable cytokine clearance in septic patients with acute kidney injury.

Endotoxin adsorption: Direct hemoperfusion with the polymyxin B-immobilized fiber column (PMX)

Toraymyxin^® is a medical device developed to adsorb circulating endotoxins in the blood using direct hemoperfusion therapy for patients with septic shock. In 1994, the Japanese National Health Insurance system approved the use of Toraymyxin for the treatment of endotoxemia and septic shock. Since then, Toraymyxin has been safely used in more than 100,000 cases in emergency and intensive care units in Japan. Toraymyxin is currently available for use in the clinical setting in 14 countries worldwide. In this study, we reviewed and introduced the development, clinical use, and efficacy of Toraymyxin and commented on its anticoagulant use and cartridge clotting issue in the treatment of severe sepsis and septic shock. We also highlighted potential new applications of Toraymyxin for longer duration therapy and pulmonary diseases.

History and current status of polymyxin B-immobilized fiber column for treatment of severe sepsis and septic shock

Toraymyxin^® (Toray Medical Co., Ltd, Tokyo, Japan) has been developed as a direct hemoperfusion column that contains polymyxin B‐immobilized fiber to bind endotoxins in patients’ blood. Toraymyxin was approved by the Japanese National Health Insurance system for the treatment of endotoxemia and septic shock in 1994. Since then, PMX (defined as direct hemoperfusion with Toraymyxin) has been safely used in more than 100 000 cases in emergency and intensive care units in Japan. Toraymyxin is currently available for use in clinical settings in 12 countries outside of Japan. We reviewed and analyzed the development, clinical use, and efficacy of Toraymyxin, and assessed the current status of Toraymyxin use for the treatment of severe sepsis and septic shock. Our review shows that PMX appeared to be effective in improving hemodynamics and respiratory function in septic shock requiring emergency abdominal surgery. Recent large‐scale ranomized controlled trialscould not demonstrate whether prognosis is improved by PMX. However, the latest meta‐analysis revealed that PMX significantly decreased mortality in patients with severe sepsis and septic shock. Combination of PMX with continuous hemodiafiltration and longer duration of PMX might be an effective strategy to improve survival in such patients.

Prolonged direct hemoperfusion using a polymyxin B immobilized fiber cartridge provides sustained circulatory stabilization in patients with septic shock: a retrospective observational before-after study

BACKGROUND

Direct hemoperfusion therapy with polymyxin B immobilized fiber cartridges (PMX-DHP) is widely used for septic shock in Japan and parts of Europe. Although this treatment is usually administered for 2 h, the optimal duration has not been established.

METHODS

This retrospective study compared the effects of prolonged and conventional PMX-DHP durations (2 and 12 h, respectively) for septic shock. Between October 2013 and March 2015, 18 patients underwent conventional PMX-DHP, and between April 2015 and May 2016, 18 patients underwent prolonged PMX-DHP. The primary outcome was the vasopressor dependency index during the 12 h after starting the first PMX-DHP session. The vasopressor dependency index was calculated as (inotropic score)/(mean blood pressure).

RESULTS

The patients' characteristics were almost similar in the conventional and prolonged PMX-DHP groups. The major site of infection was the abdomen in both groups (61 and 72%, respectively). The conventional PMX-DHP group had mean blood pressure values of 68.4 ± 8.9 mmHg and 78.2 ± 16.9 mmHg at 0 and 12 h after starting PMX-DHP (P = 0.13). The prolonged PMX-DHP group had mean blood pressure values of 70.3 ± 15.7 mmHg and 87.7 ± 16.9 mmHg at 0 and 12 h after starting PMX-DHP (P = 0.004). The conventional PMX-DHP group had vasopressor dependency index values of 0.52 ± 0.29 and 0.39 ± 0.25 at 0 and 12 h after starting PMX-DHP (P = 0.29). The prolonged PMX-DHP group had vasopressor dependency index values of 0.50 ± 0.26 and 0.28 ± 0.18 at 0 and 12 h after starting PMX-DHP (P = 0.01). Hospital mortality was similar in both groups (8/18 [44%] and 8/18 [44%]).

CONCLUSIONS

These findings suggest that prolonged PMX-DHP provides more sustained circulatory stabilization compared to conventional PMX-DHP. However, our study failed to detect any improvement in mortality. Well-designed prospective trials are needed to examine the clinical outcomes of prolonged PMX-DHP and to identify the optimal duration of PMX-DHP.

Efficacy of direct hemoperfusion with a polymyxin B-immobilized fiber column in miliary tuberculosis

Case

A 75‐year‐old woman presented with a 10‐day history of intermittent fever, general fatigue, and progressive dyspnea. Although she had a low PaO₂/FIO₂ ratio, the cause of acute respiratory distress syndrome was not clear until day 9 in hospital.

Outcome

We treated the patient with direct hemoperfusion with a polymyxin B‐immobilized fiber column incidentally; the PaO₂/FIO₂ ratio improved following this therapy. Acid‐fast bacilli, which were not seen in the sputum on admission, were detected in cultures from sputum, urine, bone marrow, liver biopsy, and blood samples, with a real‐time polymerase chain reaction assay confirming tuberculosis. She was immediately transferred to a specialized tuberculosis hospital, and after a 3‐month treatment, was discharged.

Conclusion

Treatment with polymyxin B‐immobilized fiber column may provide good results for pulmonary oxygenation in acute respiratory distress syndrome caused by tuberculosis.

Initial central venous pressure could be a prognostic marker for hemodynamic improvement of polymyxin B direct hemoperfusion: a retrospective cohort study

BACKGROUND

Direct hemoperfusion with polymyxin B-immobilized fiber column (PMX-DHP) could improve the hemodynamic status of septic shock patients. As PMX-DHP is an invasive and costly procedure, it is desirable to estimate the therapeutic effect before performing the therapy. However, it is still unclear when this therapy should be started and what type of sepsis it should be employed for. In this study, we retrospectively examined the clinical effect of patients treated with PMX-DHP by using central venous pressure (CVP).

METHODS

Seventy patients who received PMX-DHP for septic shock during the study period were recruited and divided into a low CVP group (n = 33, CVP < 12 mmHg) and a high CVP group (n = 37, CVP≧12 mmHg). The primary endpoint was vasopressor dependency index at 24 hours after starting PMX-DHP, and the secondary endpoint was the 28-day survival rate. Additionally, we performed a multivariate linear regression analysis on the difference in the vasopressor dependency index.

RESULTS

The vasopressor dependency index significantly improved at 24 h in the low CVP group (0.33 to 0.16 mmHg^-1; p < 0.01) but not in the high CVP group (0.43 to 0.34 mmHg^-1; p = 0.41), and there was a significant difference between the two groups in the index at 24 h (p = 0.02). The 28-day survival rate was higher in the low CVP group (79 vs. 43 %; p < 0.01). Multivariate linear regression analysis showed that CVP (p = 0.04) was independently associated with the difference in the vasopressor dependency index.

CONCLUSIONS

Our study indicates that the clinical effect of PMX-DHP for septic shock patients with higher CVP (≧12 mmHg) might be limited and that the initial CVP when performing PMX-DHP could function as an independent prognostic marker for the hemodynamic improvement.