S(+)-ketamine, the pure dextrorotatory enantiomer of ketamine has been available for clinical use in analgesia and anesthesia for more than 25 years. The main effects are mediated by non-competitive inhibition of the N-methyl-D-aspartate (NMDA) receptor but S(+)-ketamine also interacts with opioid receptors, monoamine receptors, adenosine receptors and other purinergic receptors. Effects on α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, metabotropic glutamate receptors (mGluR) and L‑type calcium chanels have also been described. S(+)-ketamine stimulates the sympathetic nerve system, making it an ideal drug for analgosedation or induction of anesthesia in instable patients. In addition, the neuroprotective properties, bronchodilatory, antihyperalgesic or antiepileptic effects provide interesting therapeutic options. In this article we discuss the numerous effects of S(+)-ketamine under pharmacological and clinical aspects especially for typical indications in emergency medicine as well as intensive care.

Introduction: Acute respiratory failure (ARF) is the main reason for intensive care unit (ICU) admissions in patients with hematologic malignancies (HMs). We report the first series of adult patients with ARF and HMs treated with extracorporeal membrane oxygenation (ECMO). Methods: This is a retrospective cohort study of 14 patients with HMs (aggressive non-Hodgkin lymphoma (NHL) n = 5; highly aggressive NHL, that is acute lymphoblastic leukemia or Burkitt lymphoma, n = 5; Hodgkin lymphoma, n = 2; acute myeloid leukemia, n = 1; multiple myeloma, n = 1) receiving ECMO support because of ARF (all data as medians and interquartile ranges; age, 32 years (22 to 51 years); simplified acute physiology score II (SAPS II): 51 (42 to 65)). Etiology of ARF was pneumonia (n = 10), thoracic manifestation of NHL (n = 2), sepsis of nonpulmonary origin (n = 1), and transfusion-related acute lung injury (n = 1). Diagnosis of HM was established during ECMO in four patients, and five first received (immuno-) chemotherapy on ECMO. Results: Before ECMO, the PaO₂/FiO₂ ratio was 60 (53 to 65), (3.3 to 3.7). Three patients received venoarterial ECMO because of acute circulatory failure in addition to ARF; all other patients received venovenous ECMO. All patients needed vasopressors, and five needed hemofiltration. Thrombocytopenia occurred in all patients (lowest platelet count was 20 (11 to 21) G/L). Five major bleeding events were noted. ECMO duration was 8.5 (4 to 16) days. ICU and hospital survival was 50%. All survivors were alive at follow-up (36 (10 to 58) months); five patients were in complete remission, one in partial remission, and one had relapsed. Conclusions: ECMO therapy is feasible in selected patients with HMs and ARF and can be associated with long-term disease-free survival.

To investigate the impact of prophylactic continuous lateral rotation therapy on the prevalence of ventilator-associated pneumonia, duration of mechanical ventilation, length of stay, and mortality in critically ill medical patients. Prospective, randomized, clinical study. Three medical intensive care units of an university tertiary care hospital. Patients were randomized to continuous lateral rotation therapy or standard care if they were mechanically ventilated for 10(4) colony-forming units/mL in bronchoalveolar lavage. Radiologists were blinded to randomization whereas clinical outcome assessors were not. Rotation therapy was performed continuously in a specially designed bed over an arc of 90 degrees. Additional measures to prevent ventilator-associated pneumonia were equally standardized in both groups including semirecumbent position. Ventilator-associated pneumonia frequency during the intensive care unit stay was 11% in the rotation group and 23% in the control group (p = .048), respectively. Duration of ventilation (8 +/- 5 vs. 14 +/- 23 days, p = .02) and length of stay (25 +/- 22 days vs. 39 +/- 45 days, p = .01) were significantly shorter in the rotation group. In a forward stepwise logistic regression model including the continuous lateral rotation therapy, gender, Lung Injury Score, and Simplified Acute Physiology Score II, continuous lateral rotation therapy just failed to reach statistical significance with respect to development of ventilator-associated pneumonia (p = .08). Intolerance to continuous lateral rotation therapy during the weaning phase was observed in 29 patients (39%). Mortality was comparable in both groups. Ventilator-associated pneumonia prevalence was significantly reduced by continuous lateral rotation therapy. Continuous lateral rotation therapy led to shorter ventilation time and length of stay. Continuous lateral rotation therapy should be considered in ventilated patients at risk for ventilator-associated pneumonia as a feasible method exerting additive effects to other preventive measures.

In patients awaiting lung transplantation (LTX), adequate gas exchange may not be sufficiently achieved by mechanical ventilation alone if acute respiratory decompensation arises. We report on 20 patients with life-threatening hypercapnia who received extracorporeal CO2 removal (ECCO2-R) by means of the interventional lung assist (ILA®, Novalung) as bridge to LTX. The most common underlying diagnoses were bronchiolitis obliterans syndrome, cystic fibrosis, and idiopathic pulmonary fibrosis, respectively. The type of ILA was pumpless arteriovenous or pump-driven venovenous (ILA activve®, Novalung) in 10 patients each. ILA bridging was initiated in 15 invasively ventilated and five noninvasively ventilated patients, of whom one had to be intubated prior to LTX. Hypercapnia and acidosis were effectively corrected in all patients within the first 12 h of ILA therapy: PaCO2 declined from 109 (70-146) to 57 (45-64) mmHg, P < 0.0001; pH increased from 7.20 (7.06-7.28) to 7.39 (7.35-7.49), P < 0.0001. Four patients were switched to extracorporeal membrane oxygenation due to progressive hypoxia or circulatory failure. Nineteen patients (95%) were successfully transplanted. Hospital and 1-year survival was 75 and 72%, respectively. Bridging to LTX with ECCO2-R delivered by arteriovenous pumpless or venovenous pump-driven ILA is feasible and associated with high transplantation and survival rates.

Introduction: Prone position is known to improve oxygenation in patients with acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS). Supine upright (semirecumbent) position also exerts beneficial effects on gas exchange in this group of patients. We evaluated the effect of combining upright and prone position on oxygenation and respiratory mechanics in patients with ALI or ARDS in a prospective randomized cross-over study. Methods: After turning them prone from a supine position, we randomized the patients to a prone position or combined prone and upright position. After 2 hours, the position was changed to the other one for another 6 hours. The gas exchange and static compliance of the respiratory system, lungs, and chest wall were assessed in the supine position as well as every hour in the prone position. Results: Twenty patients were enrolled in the study. The PaO₂/FiO₂ ratio improved significantly from the supine to the prone position and further significantly increased with additional upright position. Fourteen (70%) patients were classified as responders to the prone position, whereas 17 (85%) patients responded to the prone plus upright position compared with the supine position (P = n.s.). No statistically significant changes were found with respect to compliance. Conclusions: Combining the prone position with the upright position in patients with ALI or ARDS leads to further improvement of oxygenation. Trial registration: Clinical Trials No. NCT00753129