Alexander Hermann

First experience with a new miniaturized pump-driven venovenous extracorporeal CO2 removal system (iLA Activve): a retrospective data analysis.

iLA Activve is a new minimally invasive device for extracorporeal CO2 removal (ECCO2-R) using a miniaturized pump, a special gas exchange membrane, and a double-lumen cannula. We retrospectively analyzed our experiences in 12 patients with hypercapnic respiratory failure undergoing ECCO2-R. Indication for ECCO2-R was hypercapnia due to terminal lung failure during bridging to lung transplantation, pneumonia, and chronic obstructive lung disease or asthma. The median duration of ECCO2-R was 8 days (range 2–30). Seven patients were successfully weaned and five died. Patients with primarily hypoxic lung failure were significantly longer ventilated before ECCO2-R and had a higher mortality rate. Complications were retroperitoneal hematoma after cannulation in one patient and repeated system changes because of clotting in two patients. We observed effective CO2 removal in all patients, with significant reduction in ventilation pressures and minute volumes at median blood flow rates of 1.2–1.4 L/min. The iLA Activve system using venous double-lumen cannulas proved to be an effective method for ECCO2-R. Invasiveness of ventilation could be reduced. Additional severe impairment of oxygenation and prolonged mechanical ventilation before ECCO2-R are factors of adverse prognosis. The use of ECCO2-R should be thoroughly reconsidered in these cases.

Influence of different oxygenator types on changing frequency, infection incidence, and mortality in ARDS patients on veno-venous ECMO

Purpose Veno-venous extracorporeal membrane oxygenation (vv-ECMO) is pivotal in the treatment of patients suffering from acute respiratory distress syndrome (ARDS). Comparative data with different oxygenator models have not yet been reported. The aim of this retrospective investigation was therefore to assess whether different oxygenator types might influence changing frequency, infection incidence, and mortality in patients on vv-ECMO. Methods 42 patients undergoing vv-ECMO between 1998 and 2009 were identified. In 20 out of these patients, a polypropylene (PP) microporous hollow fiber membrane oxygenator, and in 22 patients a nonmicroporous polymethylpentene (PMP) diffusion membrane oxygenator was used. Infection incidence, changing frequency, and mortality were documented. Results In the PMP group, an oxygenator change was necessary less often than in the PP group (p<0.001). The incidence of bacterial, viral, or fungal growth was similar in the groups, thus independent of the frequency of oxygenator change. Irrespective of the groups, the occurrence of Candida sp. tended to correlate with death (p = 0.06). In general, there was a trend towards a higher infection incidence in the subgroup with pulmonary ARDS (p = 0.07). Moreover, infection incidence was associated with a longer ICU stay (p = 0.03) and longer ECMO therapy (p = 0.03). ICU mortality was lower in the PMP group than in the PP group, although not statistically significant (p = 0.10). Conclusions The PMP oxygenator membranes showed benefits with regards to changing frequency, but not infection incidence, length of ICU stay, and length of ECMO therapy. There was a trend towards a lower ICU mortality in patients with PMP oxygenators.

Incidence of intensive care unit admission, outcome and post intensive care survival in patients with diffuse large B-cell lymphoma

Abstract Some patients with diffuse large B-cell lymphoma (DLBCL) require intensive care unit (ICU) admission prior to or during chemotherapy. We analyzed all unscheduled ICU admissions in 331 consecutive patients (18–93 years) with newly diagnosed DLBCL. Thirty-seven patients (11.2%) required ICU treatment primarily due to hemodynamic (37.8%) or respiratory failure (24.3%). Bulky disease and high IPI score were predictive of ICU admission in the early course. ICU and hospital survival was 75.7% and 70.3%, respectively. Overall survival in ICU patients with newly diagnosed DLBCL was worse compared to non-ICU-patients (40.7% vs. 72.7% at two years). However, survival of high-risk patients (IPI 3–5), continuous complete remission, and disease-free survival did not differ. Post-ICU survival was poor in patients with relapsed/refractory DLBCL (0.1–10 months). Our observations favor unrestricted ICU support in DLBCL patients undergoing first-line therapy. ICU referral of patients with refractory/relapsed disease must be evaluated in the context of the hematologic prognosis.

A surge of flu-associated adult respiratory distress syndrome in an Austrian tertiary care hospital during the 2009/2010 Influenza A H1N1v pandemic.

ZusammenfassungWir berichten über 17 Patienten mit Influenza A H1N1v assoziiertem schweren Lungenversagen (ARDS), welche zwischen 11. Juni 2009 und 10. August 2010 an einer Intensivstation (ICU) aufgenommen wurden (w/m: 8/9; Alter: median 39 (IQR 29–54) Jahre; SAPS II: 35 (29–48)). Der Body Mass Index war 26 (24–35); 24 % waren übergewichtig und 29% fettleibig. Der Charlson Comorbidity Index war 1 (0–2) und nur ein Patient hatte keinerlei Vorerkrankungen. Die mediane Zeit zwischen Symptombeginn und ICU Aufnahme betrug 5 Tage (Range 0–14). Keiner der Patienten hatte eine H1N1v Vakzine erhalten. Neun Patienten erhielten Oseltamivir, jedoch lediglich zwei innerhalb der ersten 48 Stunden nach Symptombeginn. Alle Patienten entwickelten ein schweres ARDS (PaO2/FiO2-Ratio: 60 (55–92); lung injury score: 3.8 (3,3–4,0)), waren maschinell beatmet und benötigten Vasopressoren. Vierzehn Patienten erhielten Corticosteroide, 7 wurden hämofiltriert, und 10 Patienten benötigten extrakoporale Membranoxygenation (ECMO; 8 Patienten veno-venös, 2 Patienten veno-arteriell). Drei Patienten erhielten eine ILA (Intenventional Lung Assist), und 2 Patienten eine pumpengetriebene extrakorporale low-flow CO2-Elimination. Sieben von 17 Patienten (41 %) verstarben auf der Intensivstation (4 aufgrund von Blutungen, 3 aufgrund von Multiorganversagen), alle anderen überlebten das Krankenhaus (59 %). Die ECMO-Mortalität betrug 50 %. Die mediane ICU Liegedauer betrug 26 (19–44) vs. 21 (17–25) (Überlebende vs. Nichtüberlebende), die Beatmungsdauer 18 (14–35) vs. 20 (17–24), und die ECMO Dauer 10 (8–25) vs. 13 (11–16) Tage (p = n.s.). Verglichen mit einer Kontrollgruppe von 241 erwachsenen ICU Patienten ohne H1N1v war die Liegedauer, Beatmungsrate, Beatmungsdauer, und der TISS 28 Score bei Patienten mit H1N1v signifikant höher. Die Kontrollgruppe bot ein tendeziell höheres ICU-Überleben (79 vs. 59 %; p = 0,06). Patienten mit H1N1v an unseren ICUs waren jung, überproportional übergewichtig, und hatten fast alle Vorerkrankungen. Alle Patienten entwickelten ein schweres ARDS, welches unerwartet häufig mit extrakoroporalem Gasaustausch behandelt werden musste. Patienten mit H1N1v hatten kompliziertere Verläufe verglichen mit Kontrollpatienten.SummaryWe report on 17 patients with influenza A H1N1v-associated Adult Respiratory Distress Syndrome who were admitted to the intensive care unit (ICU) between June 11th 2009 and August 10th 2010 (f/m: 8/9; age: median 39 (IQR 29–54) years; SAPS II: 35 (29–48)). Body mass index was 26 (24–35), 24% were overweight and 29% obese. The Charlson Comorbidity Index was 1 (0–2) and all but one patient had comorbid conditions. The median time between onset of the first symptom and admission to the ICU was 5 days (range 0–14). None of the patients had received vaccination against H1N1v. Nine patients received oseltamivir, only two of them within 48 hours of symptom onset. All patients developed severe ARDS (PaO2/FiO2-Ratio 60 (55–92); lung injury score 3.8 (3.3–4.0)), were mechanically ventilated and on vasopressor support. Fourteen patients received corticosteroids, 7 patients underwent hemofiltration, and 10 patients needed extracorporeal membrane-oxygenation (ECMO; 8 patients veno-venous, 2 patients veno-arterial), three patients Interventional Lung Assist (ILA) and two patients pump driven extracorporeal low-flow CO2-elimination (ECCO2–R). Seven of 17 patients (41%) died in the ICU (4 patients due to bleeding, 3 patients due to multi-organ failure), while all other patients survived the hospital (59%). ECMO mortality was 50%. The median ICU length-of-stay was 26 (19–44) vs. 21 (17–25) days (survivors vs. nonsurvivors), days on the ventilator were 18 (14–35) vs. 20 (17–24), and ECMO duration was 10 (8–25) vs. 13 (11–16) days, respectively (all p = n.s.). Compared to a control group of 241 adult intensive care unit patients without H1N1v, length of stay in the ICU, rate of mechanical ventilation, days on the ventilator, and TISS 28 scores were significantly higher in patients with H1N1v. The ICU survival tended to be higher in control patients (79 vs. 59%; p = 0.06). Patients with H1N1v admitted to either of our ICUs were young, overproportionally obese and almost all with existing comorbidities. All patients developed severe ARDS, which could only be treated with extracorporeal gas exchange in an unexpectedly high proportion. Patients with H1N1v had more complicated courses compared to control patients.

Successful weaning from 65-day extracorporeal membrane oxygenation therapy in influenza-associated acute respiratory distress syndrome

Introduction Data on prolonged extracorporeal membrane oxygenation (ECMO) usage in influenza associated acute respiratory distress syndrome (ARDS) are lacking. Furthermore, no consensus exists on when to terminate ECMO treatment in refractory cases. This report highlights additional treatment measures and complications in prolonged ECMO therapy and discusses associated ethical burdens. Case report We report on a 64-year-old man with confirmed H1N1 influenza virus infection who was successfully weaned from 65-day ECMO treatment with an excellent outcome. Conclusions Our experience suggests that prolonged ECMO therapy may be provided as long as only 1-organ failure exists and no lung fibrosis occurs. Active physical therapy, facilitated by ECMO treatment, is crucial and should be performed as early as possible.

Supraclavicular Approach to the Subclavian Vein as an Alternative Venous Access Site for ECMO Cannulae? A Retrospective Comparison

Venous reperfusion and double-lumen cannulae for extracorporeal membrane oxygenation (ECMO) are usually inserted via the right internal jugular vein. The supraclavicular approach to the right or left subclavian vein could serve as a possible alternative. The aim of this analysis was to compare feasibility, complications, and performance of supraclavicular and jugular cannulation. We retrospectively analyzed charts and registry data of patients undergoing venovenous ECMO. Twenty-four patients underwent jugular cannulation, and 11 patients underwent supraclavicular cannulation. Ten patients underwent femoro-jugular, and five patients underwent femoro-supraclavicular ECMO. Double-lumen cannulae were inserted via the jugular approach in 14 patients and via the supraclavicular approach in 6 patients. No cannulation-associated complications but for a single minor bleeding from the insertion site of a supraclavicular double-lumen cannula were recorded. Performance of the extracorporeal circuit was comparable between jugular and supraclavicular groups but for a more pronounced oxygenation effect in the supraclavicular double-lumen group caused by higher blood flows via larger (24 F) cannulae. The supraclavicular approach seems safe and equivalent to jugular cannulation and could serve as a valid alternative.

Discrepancy between blood gas concentration measurements and carbon dioxide removal rate: response to comments by Du et al.

Dear Editor, Du et al. [1] raise concerns regarding the calculation methods of CO2 content and the CO2 removal rate as reported in our study to describe the gas exchange performance of a novel ECCO2-R system [2]. We used standard equations for calculation of gas exchange through the membrane. These equations were derived from the literature [3] and were directly adopted into our study. We suspect a clerical rather than a calculation error as values consistently show credible data. However, we want to thank the authors for pointing out this mistake. We also appreciate their comment on the limitation of the Henderson–Hasselbalch equation. Possible factors biasing its results still remain temperature and pH values as shown in an early study by Severinghaus et al. [4]. Indeed, direct CO2 concentration measurement at the oxygenator outlet port as used by Du et al. [1] is a sophisticated alternative to blood gas-derived calculation, eliminating the chance of miscalculation and associated errors. We thankfully take these restrictions into account. The data obtained in one exemplary patient receiving veno-venous ECMO due to postcardiotomy ARDS are highly interesting. CO2 removal rate calculated according to the aforementioned equations seems to overrate the results of direct measurement conducted with the CO2 Sampling Data Logger. The authors consequently hypothesize an overestimation of the real decarboxylation rate in our study. Even though this assumption is based upon a single case, the measured difference of 19.35 mL/min (98.55 vs. 79.2 mL/min) must not be disregarded. Further investigations are required to corroborate this interesting hypothesis in an adequately representative patient population. However, we would like to emphasize the major key point of our study, which refers to the changes in patients’ arterial blood gas pressures. These values reflect the clinical therapeutic goal of extracorporeal gas exchange rather than any transmembranous partial pressure difference and regardless of the limitations of a chemical equation. In our study, changes in arterial blood gases were achieved by changes in blood and sweep gas flow, respectively, while patient-related factors like hemodynamics and respiration were kept stable and unchanged.