Coagulation abnormalities in patients with COVID-19 on venovenous ECLS increased risk for technical complications and support times but had no impact on survival.

BACKGROUND: Patients with severe coronavirus disease-19 (COVID-19)-associated acute respiratory distress on venovenous extracorporeal lung support (V-V ECLS) showed a high incidence of vascular as well as ECLS-related thrombotic complications. The latter may influence the outcome of the patients. METHODS: This is a retrospective monocentric study on prospectively collected data of technical complications including 69 adult COVID-19 patients on V-V ECLS (ECLS Registry, March 2020 until April 2021) without and with system exchanges. Alterations in ECLS-specific data, hemolysis, coagulation, and hemostasis parameters were analyzed. RESULTS: Every second COVID-19 patient on V-V ECLS developed technical complications. Optimized ECLS management at our ECLS center reduced cases of acute clot formation (pump head thrombosis, acute oxygenator thrombosis) (17%), and allowed early identification of progressive clotting processes (worsened gas transfer, coagulation disorder) (14%, 54%) with a significant overhang of hyperfibrinolysis (37%). Although COVID-19 disease and technical complications caused the prolonged length of stay at the intensive care unit and ECLS support times, the proportion of successful weaning and survival rates were comparable with patients without system exchange. CONCLUSION: The survival of ECLS patients with COVID-19 was independent of the requirement for system exchange due to technical-induced coagulation disorders. Close monitoring for circuit clotting is mandatory in COVID-19 patients and is one prerequisite for successful organ support in these difficult patients.

Bail-out treatment of pulmonary embolism using a large-bore aspiration mechanical thrombectomy device.

We report on the first pulmonary embolism treatment via the large-bore aspiration mechanical thrombectomy device (Inari FlowTriever®) outside the USA, in a resuscitated patient on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) suffering from severe and acute right heart failure. In this particular high-risk patient population, where thrombolysis is mostly not applicable, this new technology could be a promising solution as the combination of large-bore thrombus aspiration and extraction successfully removes large emboli. In our case, right ventricular function improved rapidly after the procedure, ECMO could be weaned, and the patient was dismissed 2 weeks after. In summary, we provide a new therapeutic option for the often difficult treatment of pulmonary embolism in high-risk patients on VA-ECMO.

Autopsy findings after long-term treatment of COVID-19 patients with microbiological correlation.

Between April and June 2020, i.e., during the first wave of pandemic coronavirus disease 2019 (COVID-19), 55 patients underwent long-term treatment in the intensive care unit at the University Hospital of Regensburg. Most of them were transferred from smaller hospitals, often due to the need for an extracorporeal membrane oxygenation system. Autopsy was performed in 8/17 COVID-19-proven patients after long-term treatment (mean: 33.6 days). Autopsy revealed that the typical pathological changes occurring during the early stages of the disease (e.g., thrombosis, endothelitis, capillaritis) are less prevalent at this stage, while severe diffuse alveolar damage and especially coinfection with different fungal species were the most conspicuous finding. In addition, signs of macrophage activation syndrome was detected in 7 of 8 patients. Thus, fungal infections were a leading cause of death in our cohort of severely ill patients and may alter clinical management of patients, particularly in long-term periods of treatment.

Influence of early elective tracheostomy on the incidence of postoperative complications in patients undergoing head and neck surgery.

BACKGROUND: The incidence of postoperative complications after head and neck surgery is high. This study evaluated the influence of early elective tracheostomy on the incidence of postoperative pneumonia and delirium. METHODS: We reviewed the data of all patients who had undergone removal of an oropharyngeal tumor and microsurgical tissue transfer at our department in a two year period. Pearson's Chi-squared test and the Fischer's exact t-test were then used to measure the influence of patients' preexisting conditions and risk factors and of early elective tracheostomy on the incidence of postoperative complications. RESULTS: In total, 47 cases were analyzed. Patients with an endotracheal tube were ventilated for a longer time (3.4 days vs. 1.5 days) and were transferred to the regular ward later (after 6.9 days vs. 4.7 days) than patients with tracheostomy. Only 1 (2.1%) of the patients with a tracheostomy developed pneumonia in contrast to 5 intubated patients (10.6%) and only 2 patients with a tracheostomy developed postoperative delirium (9.5%) in contrast to 8 intubated patients (30.8%). CONCLUSION: Early primary tracheostomy in patients undergoing resection of oropharyngeal cancer seems to have numerous benefits, such as lower complication rates with regard to pneumonia and postoperative delirium and shorter duration of both mechanical ventilation and intensive care unit (ICU) stays. Further studies have to evaluate if these benefits also influence morbidity and mortality rates.

Inventory of a Neurological Intensive Care Unit: Who Is Treated and How Long?

Purpose. To characterize indications, treatment, and length of stay in a stand-alone neurological intensive care unit with focus on comparison between ventilated and nonventilated patient. Methods. We performed a single-center retrospective cohort study of all treated patients in our neurological intensive care unit between October 2006 and December 2008. Results. Overall, 512 patients were treated in the surveyed period, of which 493 could be included in the analysis. Of these, 40.8% had invasive mechanical ventilation and 59.2% had not. Indications in both groups were predominantly cerebrovascular diseases. Length of stay was 16.5 days in mean for ventilated and 3.6 days for nonventilated patient. Conclusion. Most patients, ventilated or not, suffer from vascular diseases with further impairment of other organ systems or systemic complications. Data reflects close relationship and overlap of treatment on nICU with a standardized stroke unit treatment and suggests, regarding increasing therapeutic options, the high impact of acute high-level treatment to reduce consequential complications.

A comparison of three supraglottic airway devices used by healthcare professionals during paediatric resuscitation simulation.

OBJECTIVE: The aim of this study was to determine the best airway device among the laryngeal mask, I-gel and the laryngeal tube used by healthcare professional groups with different levels of experience with paediatric airway management. METHOD: Three groups of healthcare professionals were separately provided with brief supervised training in using the three devices. Afterwards the participants were asked to place the airway device. For every participant, the positioning of each device was recorded. The success rate and timing of insertion were measured. Furthermore, each insertion was scored for the ease of insertion, clinical and fibreoptic verification of the position and successful ventilation. RESULTS: A total of 66 healthcare providers (22 paramedics, 22 nurse anaesthetists and 22 anaesthesia residents) participated in the study. The median time of insertion of both the laryngeal mask and the tube was significantly longer than for the I-gel for all professional groups (p<0.001). The success rate with the I-gel was higher than that with the laryngeal mask or tube (p<0.001). Except for the laryngeal mask, there were no differences among the professional groups regarding the fibreoptic evaluation. CONCLUSIONS: In terms of both the time required for successful placement and the rate of successful placement, the I-gel is superior to the laryngeal mask and tube in paediatric resuscitation simulations by healthcare professional groups with different levels of experience with paediatric airway management.

No change in the regional distribution of tidal volume during lateral posture in mechanically ventilated patients assessed by electrical impedance tomography.

We assessed the distribution of regional lung ventilation during moderate and steep lateral posture using electrical impedance tomography (EIT) in mechanically ventilated patients. Seven patients were placed on a kinetic treatment table. An elastic belt containing 16 electrodes was placed around the chest and was connected to the EIT device. Patients were moved to left and right lateral positions in a stepwise (10 degrees ) mode up to 60 degrees. EIT images [arbitrary units (AU)] were generated and scanned for assessment of relative ventilation distribution changes [tidal volume (V(T))]. A calibration procedure of arbitrary units (AUs) versus ventilator-derived V(T) performed in all patients during three predefined positions (supine, 60 degrees-left dependent and 60 degrees-right-dependent) showed a significant correlation between V(T) in supine, left and right lateral positions with the corresponding AUs (r(2) = 0.356, P<0.05). Changes in V(T) were calculated and compared to supine position, and specific regions of interest (ROIs) were analysed. In our study, in contrast to recent findings, a change in lateral positions did not induce a significant change in regional tidal volume distribution. In right lateral positions, a broader variation of V(T) with a trend towards an increase in the dependently positioned lung was observed in comparison with supine. Lateral positioning promotes the redistribution of ventilation to the ventral regions of the lung. The use of EIT technology might become a helpful tool for understanding and guiding posture therapy in mechanically ventilated patients.

Bilateral vertebral artery occlusion with retrograde basilary flow in three cases of giant cell arteritis.

Vertebrobasilar ischaemia is a rare life-threatening complication in giant cell arteritis (GCA). We report three patients with bilateral vertebral artery occlusion. Neurovascular imaging, including CT-angiography, MR-angiography and colour-coded duplex sonography revealed flow reversal in the basilar artery as well as inflammation of the vertebral vessel wall. The first patient died from massive brainstem infarction, the other two patients survived the initial inflammatory phase of GCA. No stroke recurrence at 12 months' follow-up on warfarin and steroid treatment was observed. Bilateral distal vertebral artery occlusion and retrograde basilar artery flow persisted.Outcome in these patients is dependant on potent immunosuppression, concurrent atherosclerotic steno-occlusive disease and presence and/or rapid development of sufficient collateral pathways into the vertebrobasilar circulation. The identification of patients with high risk of ischaemia due to compromised vertebrobasilar flow may be important to select adjunct treatment to immunosuppression, such as anticoagulation in GCA.

Recurrent cardiac arrest caused by lateral medulla oblongata infarction.

Cardiac arrest is a rare complication in Wallenberg syndrome, despite the fact that the brainstem, especially the lower medulla, modulates sympathetic and parasympathetic activity. In the case reported here, a 45-year-old man was admitted with clinical symptoms of Wallenberg syndrome, including right sided hemiparesis secondary to dissection of the right vertebral artery. During the following days he experienced several spells of self limiting cardiac arrests, which made the implantation of a pacemaker necessary. Magnetic resonance imaging scan showed an infarction on the lower right and dorsolateral medulla. This might have affected the central sympathetic neurons which normally inhibit the nucleus of the solitary tract. The disinhibition of the nucleus tractus solitarii may have led to an increase of parasympathetic outflow resulting in bradycardia/asystolia. This case report describes a rare indication for transient or permanent therapy with a cardiac pacemaker in Wallenberg syndrome.

Four years' experience with a miniaturized extracorporeal circulation system and its influence on clinical outcome.

It has been suggested that the morbidity associated with cardiopulmonary bypass can be attributed in part to the blood-material and blood-air interactions in the extracorporeal circulation (ECC). A recently introduced minimized ECC-system (MECC System) should be able to reduce these negative effects associated with ECC. A retrospective analysis was performed comprising 485 patients who were operated on for elective coronary artery bypass grafting (CABG) using the MECC System with intermittent antegrade warm blood cardioplegia (group 1) from January 2000 to February 2004. A control group consisted of 485 patients (group 2) undergoing elective CABG in the same period using a conventional ECC and cold crystalloid cardioplegia. There were no significant differences between the two groups in terms of the duration of intubation following surgery, the length of intensive care unit-stay and the total hospital stay. Although the 30-day mortality was similar between the two groups, the incidence of postoperative complications and the perioperative use of blood products were significantly higher in the control group compared to the MECC group. The MECC System may serve as an alternative and less invasive approach to conventional ECC.

In vivo uptake and elimination of isoflurane by different membrane oxygenators during cardiopulmonary bypass.

BACKGROUND: Volatile anesthetics are frequently used during cardiopulmonary bypass (CPB) to maintain anesthesia. Uptake and elimination of the volatile agent are dependent on the composition of the oxygenator. This study was designed to evaluate whether the in vivo uptake and elimination of isoflurane differs between microporous membrane oxygenators containing a conventional polypropylene (PPL) membrane and oxygenators with a new poly-(4-methyl-1-pentene) (PMP) membrane measuring isoflurane concentrations in blood. METHODS: Twenty-four patients undergoing elective coronary bypass surgery with the aid of CPB were randomly allocated to one of four groups, using either one of two different PPL-membrane oxygenators for CPB or one of two different PMP-membrane oxygenators. During hypothermic CPB, 1% isoflurane in an oxygen-air mixture was added to the oxygenator gas inflow line (gas flow, 3 l/min) for 15 min. Isoflurane concentration was measured in blood and in exhaust gas at the outflow port of the oxygenator. Between-group comparisons were performed for the area under the curve (AUC) during uptake and elimination of the isoflurane blood concentrations, the maximum isoflurane blood concentration (C(max)), and the exhausted isoflurane concentration (F(E)). RESULTS: The uptake of isoflurane, expressed as AUC of isoflurane blood concentration and a function of F(E), was significantly reduced in PMP oxygenators compared to PPL oxygenators (P < 0.01). C(max) was between 8.5 and 13 times lower in the PMP-membrane oxygenator groups compared to the conventional PPL-membrane oxygenator groups (P < 0.01). CONCLUSIONS: The uptake of isoflurane into blood via PMP oxygenators during CPB is severely limited. This should be taken into consideration in cases using such devices.