[Anesthesia and intensive care ventilators: differences and usability in COVID-19 patients]. / Anästhesie- und Intensivbeatmungsgeräte: Unterschiede und Nutzbarkeit bei COVID-19-Patienten.

The current coronavirus disease 2019 (Covid-19) pandemia is a highly dynamic situation characterized by therapeutic and logistic uncertainties. Depending on the effectiveness of social distancing, a shortage of intensive care respirators must be expected. Concomitantly, many physicians and nursing staff are unaware of the capabilities of alternative types of ventilators, hence being unsure if they can be used in intensive care patients. Intensive care respirators were specifically developed for the use in patients with pathological lung mechanics. Nevertheless, modern anesthesia machines offer similar technical capabilities including a number of different modes. However, conceptual differences must be accounted for, requiring close monitoring and the presence of trained personnel. Modern transport ventilators are mainly for bridging purposes as they can only be used with 100% oxygen in contaminated surroundings. Unconventional methods, such as "ventilator-splitting", which have recently received increasing attention on social media, cannot be recommended. This review intends to provide an overview of the conceptual and technical differences of different types of mechanical ventilators.

[Update: acute hypercapnic respiratory failure]. / Update: akute hyperkapnische respiratorische Insuffizienz.

BACKGROUND: Hypercapnic respiratory failure is a frequent problem in critical care and mainly affects patients with acute exacerbation of COPD (AECOPD) and acute respiratory distress syndrome (ARDS). In recent years, the usage of extracorporeal CO2 removal (ECCO2R) has been increasing. OBJECTIVE: Summarizing the state of the art in the management of hypercapnic respiratory failure with special regard to the role of ECCO2R. METHODS: Review based on a selective literature search and the clinical and scientific experience of the authors. RESULTS: Noninvasive ventilation (NIV) is the therapy of choice in hypercapnic respiratory failure due to AECOPD, enabling stabilization in the majority of cases and generally improving prognosis. Patients in whom NIV fails have an increased mortality. In these patients, ECCO2R may be sufficient to avoid intubation or to shorten time on invasive ventilation; however, corresponding evidence is sparse or even missing when it comes to hard endpoints. Lung-protective ventilation according to the ARDS network is the standard therapy of ARDS. In severe ARDS, low tidal volume ventilation may result in critical hypercapnia. ECCO2R facilitates compensation of respiratory acidosis even under "ultra-protective" ventilator settings. Yet, no positive prognostic effects could be demonstrated so far. CONCLUSION: Optimized use of NIV and lung-protective ventilation remains standard of care in the management of hypercapnic respiratory failure. Currently, ECCO2R has to be considered an experimental approach, which should only be provided by experienced centers or in the context of clinical trials.

[Polytrauma following a truck accident : How to save lives by guideline-oriented emergency care]. / Polytrauma nach LKW-Unfall : Wie eine leitliniengerechte Notfallversorgung Leben retten kann.

BACKGROUND: Identification and immediate treatment of life-threatening conditions is fundamental in patients with multiple trauma. In this context, the S3 guidelines on polytrauma and the S1 guidelines on emergency anesthesia provide the scientific background on how to handle these situations. CASE STUDY: This case report deals with a seriously injured driver involved in a truck accident. The inaccessible patient showed a scalping injury of the facial skeleton with massive bleeding and partially blocked airway but with spontaneous breathing as well as centralized cardiovascular circulation conditions and an initial Glasgow coma scale (GCS) of 8. An attempt was made to stop the massive bleeding by using hemostyptic-coated dressings. In addition, the patient was intubated via video laryngoscopy and received a left and right thoracic drainage as well as two entry points for intraosseous infusion. DISCUSSION: In modern emergency medical services, treatment based on defined algorithms is recommended and also increasingly established in dealing with critical patients. The guideline-oriented emergency care of patients with polytrauma requires invasive measures, such as intubation and thoracic decompression in the preclinical setting. The foundation for this procedure includes training in theory and practice both of the non-medical and medical rescue service personnel.

[Venoarterial extracorporeal membrane oxygenation for out-of-hospital cardiac arrest. Case series of prehospital and in-hospital therapies]. / Venoarterielle extrakorporale Membranoxygenierung beim präklinischen Herz-Kreislauf-Stillstand. Fallserie prä- und innerklinischer Behandlungen.

Despite new concepts and strategies of basic and advanced life support, the outcome of patients with out-of-hospital cardiac arrest (OHCA) remains poor. The main reason accounting for these poor results is a low-flow phase during conventional cardiopulmonary resuscitation (CPR) with insufficient end organ perfusion. The early use of venoarterial extracorporeal membrane oxygenation (vaECMO) during CPR, i.e. extracorporeal resuscitation (ECPR) might improve OHCA survival rates as well as the neurological outcome in resuscitated patients. This article on a case series discusses the management of ECPR in three patients with OHCA. All patients suffered from a witnessed OHCA and received effective bystander CPR. After subsequent advanced cardiac life support could not achieve a return of spontaneous circulation (ROSC), vaECMO support was established as a bridge to therapy on site or after transportation to a primary or tertiary hospital. During the course of therapy two patients died and one patient was discharged after a full recovery. Early ECPR might improve the outcome in patients with prolonged cardiac arrest without ROSC. The use of ECPR should be based on the individual decision of an experienced ECPR team considering defined inclusion and exclusion criteria. As the outcome mainly depends on the duration and quality of conventional CPR, ECPR support should be requested immediately after establishing advanced life support (approximately 10-15 min).

[Venoarterial extracorporeal membrane oxygenation in an awake patient : Use of the mobile ECMO team for fulminant pulmonary embolism]. / Venoarterielle extrakorporale Membranoxygenierung am wachen Patienten : Einsatz des mobilen ECMO-Teams bei fulminanter Lungenarterienembolie.

The current report highlights the use of venoarterial extracorporeal membrane oxygenation (va-ECMO) in a case of pulmonary embolism complicated by right ventricular failure. A 38-year-old woman was admitted to a secondary care hospital with dyspnea and systemic hypotension. Diagnostic testing revealed a massive pulmonary embolism. Thrombolytic therapy was unsuccessful necessitating thromboendarterectomy in the presence of cardiogenic shock. To allow the necessary transport of the highly unstable patient to a tertiary care center a mobile ECMO team was called in. The team immediately initiated awake va-ECMO as a bridge to therapy. Extracorporeal support subsequently allowed a safe transportation and successful completion of the surgical procedure with complete recovery.

[Therapy of acute respiratory distress syndrome : Survey of German ARDS centers and scientific evidence]. / Therapie des akuten Lungenversagens : Umfrage an deutschen ARDS-Zentren und wissenschaftliche Evidenz.

BACKGROUND: In addition to specific treatment of the underlying cause, the therapy of acute respiratory distress syndrome (ARDS) consists of lung protective ventilation and a range of adjuvant and supportive measures. AIM: A survey was conducted to determine the current treatment strategies for ARDS in German ARDS centers. MATERIAL AND METHODS: The 39 centers listed in the German ARDS network in 2011 were asked to complete a questionnaire collecting data on the clinic, epidemiology as well as diagnostic and therapeutic measures regarding ARDS treatment. RESULTS: Of the centers 25 completed the questionnaire. In 2010 each of these centers treated an median of 31 (25-75 percentile range 20-59) patients. Diagnostic measures at admission were computed tomography of the thorax (60 % of the centers), whole body computed tomography (56 %), chest x-ray (52 %), abdominal computed tomography (32 %) and cranial computed tomography (24 %). Transesophageal echocardiography was performed in 64 %, pulmonary artery pressure was measured in 56 % and cerebral oximetry in 12 %. Sedation was regularly interrupted in 92 % of the centers and in 68 % this was attempted at least once a day. A median minimum tidal volume of 4 ml/kg (range 2-6) and a maximum tidal volume of 6 ml/kg (4-8) were used. Methods to determine the optimal positive end-expiratory pressure (PEEP) were the best PEEP method (60 %), ARDS network table (48 %), empirical (28 %), pressure volume curve (16 %), computed tomography (8 %), electrical impedance tomography (8 %) and others (8 %). Median minimum and maximum PEEPs were 10 cmH2O (range 5-15) and 21 cmH2O (15-25), respectively. Median plateau pressure was limited to 30 cmH2O (range 26-45). The respiratory rate was set below 20/min in 20 % and below 30/min in 44 %. Controlled ventilator modes were generally preferred with 80 % using biphasic positive airway pressure (BIPAP/BiLevel), 20 % pressure controlled ventilation (PCV) and 4 % airway pressure release ventilation (APRV). Assisted modes were only utilized by 8 % of the centers. Recruitment maneuvers were used by 28 %, particularly during the early phase of the ARDS. Muscle relaxants were administered by 32 % during the early phase of the ARDS. Complete prone positioning was used by 60 % of the centers, whereas 88 % utilized incomplete (135°) prone positioning. Continuous axial rotation was utilized by 16 %. Spontaneous breathing tests were used in 88 % of the centers with 60 % performing these at least once a day. Supportive therapies were frequently applied and mainly consisted of nitrous oxide (44 %), prostacycline (48 %) and corticosteroids (52 %). A restrictive fluid therapy was used in 48 % and a special nutrition regimen in 28 % of the centers. Of the participating centers 22 were able to offer extracorporeal membrane oxygenation (ECMO). In this case, respiratory therapy was modified by further reducing tidal volumes (91 %), inspiratory pressures (96 %) as well as using lower respiratory rates (≤ 8/min in 31 %). Only 9 % reduced PEEP during ECMO. Regular recruitment maneuvers were used by 14 %. Positioning maneuvers during ECMO were used by 82 %. CONCLUSIONS: Lung protective ventilation with reduced tidal volumes as well as inspiratory pressures represents the current standard of care and was utilized in all network centers. Prone positioning was widely used. Promising adjuvant therapies such as the muscle relaxation during the early phase of the ARDS, fluid restriction and corticosteroids were used less frequently. During ECMO respirator therapy was generally continued with ultraprotective ventilator settings.

[Spinal anesthesia in high-volume, low-concentration technique for Caesarean sections : Retrospective analysis]. / Spinalanästhesie zur Sectio caesarea in "High-volume-low-concentration"-Technik : Retrospektive Analyse.

BACKGROUND: Nowadays Caesarean sections are mainly undertaken using spinal anesthesia; therefore, it is important to minimize potential side effects and risks associated with this technique. Currently, many studies have been conducted to optimize the dose of local anesthetics to avoid hypotension, which often occurs during spinal anesthesia. AIM: In a retrospective study design the high-volume, low-concentration technique with up to 12 ml isobaric bupivacain 0.1% (1 mg/ml) and sufentanil (1 µg/ml), which has been used at the University Hospital Würzburg for many years was analyzed with respect to reliability and side effects. The use of this technique so far is unique among university hospitals in Germany. MATERIAL AND METHODS: Of the 1424 anesthesia protocols from 2001 to 2007 a total of 1368 were analyzed. Demographic data and parameters, such as location of puncture, dose and extent of anesthesia, hemodynamic stability and additional medication were recorded. A decrease of systolic blood pressure of more than 20% of the initial value was defined as hypotension. RESULTS: The median volume used for spinal anesthesia was 9 ml, containing 9 mg bupivacaine and 9 µg sufentanil. The rate of hypotension was 48.8 %. No significant differences in hypotension between lower and higher volumes were detectable. In 0.84% (n=12) of the cases the procedure had to be changed to general anesthesia and additional analgesia was administered in 3 cases (0.22%). CONCLUSION: The high-volume, low-concentration technique is an effective approach for spinal anesthesia with a small number of cases needing general anesthesia or additional analgesics. The rate of hypotension was moderate compared to other studies; however, because of the retrospective and non-randomized study design the dependence of this rate on dose and given volume should be interpreted with caution.

[Trauma centre admission of severely injured or critically ill patients: comparison of estimated and real arrival times]. / Schockraumaufnahme schwerverletzter oder kritisch kranker Patienten: Geschätzte und tatsächliche Eintreffzeiten im Vergleich.

BACKGROUND: During early in-hospital management of the arriving trauma patient the timing of the trauma team alert is an important organisational step. To evaluate the accordance of the estimated and the real arriving time we performed a retrospective data analysis at a level I German trauma centre. METHODS: Retrospective data analysis. Trauma team alerts from September 2010 until March 2011 were analysed. According to the hospitals pre-alert algorithm, trauma team alert took place 10 min before the estimated time of arrival. RESULTS: There were 165 trauma team alerts included in the analysis. The estimated arrival time coincided with the real arrival time in less than 10 % of cases. In 76 % of the cases, the patient arrived in an acceptable time frame with the trauma team waiting less than 14 min. In 3 % of the cases, the patient arrived prior to the trauma team. CONCLUSION: An exact estimation of the arrival time is rare. With a trauma team alert 10 min prior to the estimated time of arrival, an acceptable waiting time can be achieved. Arrival of the patient prior to the trauma team can be avoided.

Influence of apneic oxygenation and minimal tidal volumes on ventilator-associated lung injury.

BACKGROUND: Protective tidal volumes such as 6 mL/kg can still result in tidal hyperinflation and expose the lung to mechanical stress. Further reduction of tidal volume and apneic oxygenation might mitigate lung injury. We aimed to assess the influence of minimal tidal volumes and apneic oxygenation in combination with arterio-venous extracorporeal lung assist (av-ECLA) on ventilator-associated lung injury. METHODS: Acute respiratory distress syndrome was induced in swine (N.=24) by saline lavage. The animals were randomized into three groups, ventilated in a pressure-controlled mode with a tidal volume (VT) of 6 mL/kg, 3 mL/kg and 0 mL/kg body weight, respectively. The latter two groups were instrumented with an av-ECLA device. Lung injury was assessed by histological examination of lung tissue at the end of the 24 hour experiment and by gas exchange parameters. RESULTS: Oxygenation was significantly lower in the 3 and 0 mL/kg groups, whereas CO2 remained in the targeted range in all groups. Histological examination revealed a reduction of tidal hyperinflation in the apical lung regions in the 3 and 0 mL/kg groups. In lower lung regions an increase of inflammation, intra-alveolar exudation and formation of atelectasis was shown in the animals ventilated with lower VTs. CONCLUSION: In combination with highly effective CO2-removal, the reduction of tidal volumes up to 0 mL was feasible. Tidal hyperinflation could be reduced in the upper lung areas, yet inflammation in the lower lung was higher with low tidal volumes. This stresses the differing mechanical properties of inhomogeneous injured lungs.

Combination of positioning therapy and venovenous extracorporeal membrane oxygenation in ARDS patients.

Positioning therapy may improve lung recruitment and oxygenation and is part of the standard care in severe acute respiratory distress syndrome (ARDS). Venovenous extracorporeal membrane oxygenation (vvECMO) is a rescue strategy that may ensure sufficient gas exchange in ARDS patients failing conventional therapy. The aim of this case series was to describe the feasibility and pitfalls of combining positioning therapy and vvECMO in patients with severe ARDS. A retrospective cohort of nine patients is described. The patients received 20 (15-86) hours (median, 25(th) and 75(th) percentile) of positioning therapy while being treated with vvECMO. The initial PaO2/FiO2 index was 64 (51-67) mmHg and the arterial carbon dioxide tension was 60 (50-71) mmHg. Positioning therapy included 135 degrees prone, prone positioning and continuous lateral rotational therapy. During the first three days, the oxygenation index improved from 47 (41-47) to 12 (11-14) cmH2O/mmHg. The lung compliance improved from 20 (17-28) to 42 (27-43) ml/cmH2O. Complications related to positioning therapy were facial oedema (n=9); complications related to vvECMO were entrance of air (n=1) and pump failure (n=1). However, investigation of root causes revealed no association with the positioning therapy and had no documented effect on the outcome. The reported cases suggest that positioning therapy can be performed safely in ARDS patients treated with vvECMO, providing appropriate precautions are in place and a very experienced team is present.

Effects of venovenous extracorporeal membrane oxygenation on cerebral oxygenation in hypercapnic ARDS.

Extracorporeal membrane oxygenation (ECMO) is increasingly used in ARDS patients with hypoxemia and/or severe hypercapnia refractory to conventional treatment strategies. However, it is associated with severe intracranial complications, e.g. ischemic or hemorrhagic stroke. The arterial carbon dioxide partial pressure (PaCO2) is one of the main determinants influencing cerebral blood flow and oxygenation. Since CO2 removal is highly effective during ECMO, reduction of CO2 may lead to alterations in cerebral perfusion. We report on the variations of cerebral oxygenation during the initiation period of ECMO treatment in a patient with hypercapnic ARDS, which may partly explain the findings of ischemic and/or hemorrhagic complications in conjunction with ECMO.

[Acute respiratory distress syndrome and septic cardiomyopathy : successful application of veno-venoarterial extracorporeal membrane oxygenation]. / Akutes Lungenversagen und septische Kardiomyopathie : Erfolgreicher Einsatz der veno-venoarteriellen extrakorporalen Membranoxygenierung.

A 30-year-old patient was admitted to hospital with fever and respiratory insufficiency due to community acquired pneumonia. Within a few days the patient developed septic cardiomyopathy and severe acute respiratory distress syndrome (ARDS) which deteriorated under conventional mechanical ventilation. Peripheral venoarterial extracorporeal membrane oxygenation (va-ECMO) was initiated by the retrieval team of an ARDS/ECMO centre at a paO2/FIO2 ratio of 73 mmHg and a left ventricular ejection fraction (EF) of 10 %. After 12 h va-ECMO was converted to veno-venoarterial ECMO (vva-ECMO) for improvement of pulmonary and systemic oxygenation. Left ventricular function improved (EF 45 %) 36 h after starting ECMO and the patient was weaned from vva-ECMO and converted to vv-ECMO. The patient was weaned successfully from vv-ECMO after 5 additional days and transferred back to the referring hospital for weaning from the ventilator.

Whole-body multislice computed tomography (MSCT) improves trauma care in patients requiring surgery after multiple trauma.

OBJECTIVES: Whole-body multislice helical CT becomes increasingly important as a diagnostic tool in patients with multiple injuries. Time gain in multiple-trauma patients who require emergency surgery might improve outcome. The authors hypothesised that whole-body multislice computed tomography (MSCT) (MSCT trauma protocol) as the initial diagnostic tool reduces the interval to start emergency surgery (tOR) if compared to conventional radiography, combined with abdominal ultrasound and organ-focused CT (conventional trauma protocol). The second goal of the study was to investigate whether the diagnostic approach chosen has an impact on outcome. METHODS: The authors' level 1 trauma centre uses whole-body MSCT for initial radiological diagnostic work-up for patients with suspected multiple trauma. Before the introduction of MSCT in 2004, a conventional approach was used. Group I: data of trauma patients treated with conventional trauma protocol from 2001 to 2003. Group II: data from trauma patients treated with whole-body MSCT trauma protocol from 2004 to 2006. RESULTS: tOR in group I (n=155) was 120 (90-150) min (median and IQR) and 105 (85-133) min (median and IQR) in group II (n=163), respectively (p<0.05). Patients of group II had significantly more serious injuries. No difference in outcome data was found. 14 patients died in both groups within the first 30 days; five of these died within the first 24 h. CONCLUSION: A whole-body MSCT-based diagnostic approach to multiple trauma shortens the time interval to start emergency surgery in patients with multiple injuries. Mortality remained unchanged in both groups. Patients of group II were more seriously injured; an improvement of outcome might be assumed.

Hepatic effects of an open lung strategy and cardiac output restoration in an experimental lung injury.

BACKGROUND: Ventilation with high positive end-expiratory pressure (PEEP) can lead to liver dysfunction. We hypothesized that an open lung concept (OLC) using high PEEP impairs liver function and integrity dependent on the stabilization of cardiac output. METHODS: Juvenile female Pietrain pigs instrumented with flow probes around the common hepatic artery and portal vein, pulmonary and hepatic vein catheters underwent a lavage-induced lung injury. Ventilation was continued with a conventional approach (CON) using pre-defined combinations of PEEP and inspiratory oxygen fraction or with an OLC using PEEP set above the lower inflection point of the lung. Volume replacement with colloids was guided to maintain cardiac output in the CON(V+) and OLC(V+) groups or acceptable blood pressure and heart rate in the OLC(V-) group. Indocyanine green plasma disappearance rate (ICG-PDR), blood gases, liver-specific serum enzymes, bilirubin, hyaluronic acid and lactate were tested. Finally, liver tissue was examined for neutrophil accumulation, TUNEL staining, caspase-3 activity and heat shock protein 70 mRNA expression. RESULTS: Hepatic venous oxygen saturation was reduced to 18 + or - 16% in the OLC(V-) group, while portal venous blood flow decreased by 45%. ICG-PDR was not reduced and serum enzymes, bilirubin and lactate were not elevated. Liver cell apoptosis was negligible. Liver sinusoids in the OLC(V+) and OLC(V-) groups showed about two- and fourfold more granulocytes than the CON(V+) group. Heat shock protein 70 tended to be higher in the OLC(V-) group. CONCLUSIONS: Open lung ventilation elicited neutrophil infiltration, but no liver dysfunction even without the stabilization of cardiac output.

[Polytrauma management in a period of change: time analysis of new strategies for emergency room treatment]. / Polytraumamanagement im Wandel: Zeitanalyse neuer Strategien für die Schockraumversorgung.

BACKGROUND: Quality management and the early implementation of whole-body multi-slice spiral computed tomography (whole-body MSCT) are becoming increasingly important in the management of patients with multiple trauma. The aim of this study was to evaluate both components with respect to the time factor for treatment. METHODS: The investigation involved a retrospective data analysis of the time needed in the emergency room for the initial stabilization (phase A), completing the diagnosis (phase B) and the emergency room treatment (phase C). The investigation included three groups: trauma patients imaged in the emergency room with conventional imaging procedures (group I), with whole-body MSCT alone (group II) and those who were imaged with whole-body MSCT after the introduction of a quality management system with standard operating procedures (group III). RESULTS: The times for resuscitation (phase A), for diagnostic evaluation (phase B) and for total treatment (phase C) were analyzed. The times for phase A were for group I (n=79) 10 min (interquartile range, IQR 8-12 min), group II (n=82) 13 min (IQR 10-17 min) and group III (n=79) 10 min (IQR 8-15 min; p<0.001). The times for phase B were 70 min (IQR 56-85 min) for group I, 23 min (IQR 17-33 min) for group II and 17 min (IQR 13-21 min; p<0.001) for group III. For phase C the times were 82 min (IQR 66-110 min) for group I, 47 min (IQR 37-59 min) for group II and 42 min (IQR 34-52 min; p<0.05) for group III. CONCLUSION: Quality management and the early implementation of whole-body MSCT can accelerate the treatment work flow. A rapid initial diagnosis represents an important component in the high quality of treatment of polytrauma patients.

[Cholestasis and liver dysfunction in critical care patients]. / Cholostase und Leberinsuffizienz beim Intensivpatienten.

Cornerstones of the diagnostic investigations of disturbances in liver function are analysis and sophisticated evaluation of serum liver enzymes, bilirubin and ammonia. Coagulation factors, serum albumin and cholinesterase levels are indicators of the hepatic metabolic capacity. Dynamic assessment of complex liver functions allows quantification of the hepatic metabolic activity and excretory function. Imaging techniques permit visualization of the size and texture of the liver, the vascular supply and perfusion as well as an assessment of the gall bladder and the extra-hepatic and intra-hepatic bile ducts. Manifold causes for cholestasis and/or liver dysfunction are known, such as ventilation with high pressure, total parenteral nutrition, shock, hypoxia and certain drugs. Obstructive cholestasis requires reconstitution of bile duct drainage, while non-obstructive cholestasis primarily requires treatment of the causative disease. The symptomatic therapy of liver insufficiency is rarely possible via direct treatment of the cause, but mostly requires specific management of secondary organ dysfunctions related to hepatic dysfunction including circulatory failure, hepatorenal syndrome and hepatic encephalopathy. In rare cases a temporary liver surrogate is necessary. The molecular absorbent recirculating system (MARS), a form of extracorporeal albumin dialysis, is introduced as a modality for the treatment of liver failure.

Arteriovenous extracorporeal lung assist as integral part of a multimodal treatment concept: a retrospective analysis of 22 patients with ARDS refractory to standard care.

BACKGROUND AND OBJECTIVES: Pumpless arteriovenous extracorporeal lung assist is increasingly used as a rescue therapy in acute respiratory distress syndrome. Arteriovenous extracorporeal lung assist is highly efficient in eliminating carbon dioxide and allows the application of ventilator techniques that prioritize lung protection and aim to reduce ventilator-induced lung injury and remote organ dysfunction. METHODS: Retrospective data analysis performed in a 12-bed university hospital ICU. In all, 22 patients with acute respiratory distress syndrome refractory to standard care were included. Arteriovenous extracorporeal lung assist as central part of a multimodal treatment concept was combined with tidal volume (VT) reduction below 4 mL kg-1 predicted body weight, a positive end-expiratory pressure titrated to optimize oxygenation and continuous axial rotation. RESULTS: Hypercapnia was reversed within 24 h in survivors (39 mmHg (35-42) (median and interquartile range) vs. 65 mmHg (54-72), P < 0.05) and non-survivors (5.2 kPa (5.5-6.0) vs. 10 kPa (6.9-13.9), P < 0.05). Oxygenation was significantly improved in survivors after 24 h (PaO2/FiO2 ratio 20.7 kPa (17.4-22.7) vs. 11.7 kPa (7.3-20.8), P < 0.05). All patients required norepinephrine infusion and volume resuscitation. The overall complication rate was 23%, predominantly due to reversible lower limb ischaemia. One patient (5%) was permanently disabled due to amputation of a seriously injured lower leg 9 days after initiation of arteriovenous extracorporeal lung assist therapy; however, the patient survived without neurological deficits despite an initial oxygenation index of 4.4 kPa. The overall mortality rate was 27%. CONCLUSIONS: A multimodal treatment concept with arteriovenous extracorporeal lung assist as its central part provides reversal of hypercapnia and stabilization of oxygenation. In an attempt to maximize lung protection and potentially reduce ventilator-induced lung injury, a further VT reduction below 4 mL kg(-1) predicted body weight combined with a high mean airway pressure and continuous axial rotation is safely possible.

Handheld vs. conventional transesophageal echocardiography in non-cardiac surgical intensive care unit patients.

PURPOSE: We examined the feasibility of a newly developed handheld ultrasound device capable of transesophageal echocardiography (TEE). MATERIALS AND METHODS: Prospective case series in a non-cardiac surgical intensive care unit including 18 deeply sedated and endotracheally intubated critically ill non-cardiac surgical patients. The imaging quality and findings of a newly developed handheld device were compared to those of a cart-based standard TEE system. All patients were examined with both systems in a randomized order by independent examiners performing a structured and complete TEE examination. The imaging quality of the standard cardiac cross sections and spectral Doppler studies of the cardiac valves was assessed on an analog scale from 1 (excellent) to 5 (insufficient). The time requirements for each study were documented. RESULTS: We did not detect significant differences in two-dimensional imaging. Continuous-wave Doppler imaging of the left ventricular outflow tract and pulsed-wave Doppler imaging of the transmitral flow were significantly better (p <0.001) with the standard system. CONCLUSION: Handheld TEE is a goal-oriented diagnostic tool, which may sufficiently replace a standard cart-based TEE system in unstable critically ill patients when an acute gross diagnosis is required.

Early treatment with arteriovenous extracorporeal lung assist and high-frequency oscillatory ventilation in a case of severe acute respiratory distress syndrome.

BACKGROUND: Lung protective ventilation can reduce mortality in acute respiratory distress syndrome (ARDS). However, many patients with severe ARDS remain hypoxemic and more aggressive ventilation is necessary to maintain sufficient gas exchange. Pumpless arteriovenous extracorporeal lung assist (av-ECLA) has been shown to remove up to 95% of the systemic CO(2) production, thereby allowing ventilator settings and modes prioritizing oxygenation and lung protection. High-frequency oscillatory ventilation (HFOV) is an alternative form of ventilation that may improve oxygenation while limiting the risk of further lung injury by using extremely small tidal volumes (VT). METHODS: We discuss the management of a patient suffering from severe ARDS as a result of severe bilateral lung contusions and pulmonary aspiration. RESULTS: Severe ARDS developed within 4 h after intensive care unit admission. Conventional mechanical ventilation (CV) with high-airway pressures and low VT failed to improve gas exchange. Av-ECLA was initiated to achieve a less aggressive ventilation strategy. VT was reduced to 2-3 ml/kg, but oxygenation did not improve and airway pressures remained high. HFOV (8-10 Hz) was started using a recruitment strategy and oxygenation improved within 2 h. After 5 days, the patient was switched back to CV uneventfully and av-ECLA was removed after 8 days. CONCLUSION: The combination of two innovative treatment modalities resulted in rapid stabilization and improvement of gas exchange during severe ARDS refractory to conventional lung protective ventilation. During av-ECLA, extremely high oscillatory frequencies were used minimizing the risk of baro- and volutrauma.