Huadong Zhu

Severe Community-Acquired Pneumonia Caused by Human Adenovirus in Immunocompetent Adults: A Multicenter Case Series

Background Severe community-acquired pneumonia (CAP) caused by human adenovirus (HAdV), especially HAdV type 55 (HAdV-55) in immunocompetent adults has raised increasing concerns. Clinical knowledge of severe CAP and acute respiratory distress syndrome induced by HAdV-55 is still limited, though the pathogen has been fully characterized by whole-genome sequencing. Methods We conducted a multicentre retrospective review of all consecutive patients with severe CAP caused by HAdV in immunocompetent adults admitted to the Emergency Department Intensive Care Unit of two hospitals in Northern China between February 2012 and April 2014. Clinical, laboratory, radiological characteristics, treatments and outcomes of these patients were collected and analyzed. Results A total of 15 consecutive severe CAP patients with laboratory-confirmed adenovirus infections were included. The median age was 30 years and all cases were identified during the winter and spring seasons. HAdV-55 was the most frequently (11/15) detected HAdV type. Persistent high fever, cough and rapid progression of dyspnea were typically reported in these patients. Significantly increased pneumonia severity index (PSI), respiratory rate, and lower PaO2/FiO2, hypersensitive CRP were reported in non-survivors compared to survivors (P = 0.013, 0.022, 0.019 and 0.026, respectively). The rapid development of bilateral consolidations within 10 days after illness onset were the most common radiographic finding, usually accompanied by adjacent ground glass opacities and pleural effusions. Total mortality was 26.7% in this study. Corticosteroids were prescribed to 14 patients in this report, but the utilization rate between survivors and non-survivors was not significant. Conclusions HAdV and the HAdV-55 sub-type play an important role among viral pneumonia pathogens in hospitalized immunocompetent adults in Northern China. HAdV should be tested in severe CAP patients with negative bacterial cultures and a lack of response to antibiotic treatment, even if radiologic imaging and clinical presentation initially suggest bacterial pneumonia.

Pneumocystis pneumonia in patients with inflammatory or autoimmune diseases: Usefulness of lymphocyte subtyping

OBJECTIVES No consensus currently exists on the indications for Pneumocystis jirovecii prophylaxis in patients with inflammatory or autoimmune diseases. The main objective was to identify biomarkers associated with P. jirovecii pneumonia (PCP) in this population. METHODS A retrospective study was carried out at Beijing Union Medical College Hospital (2003-2014). All patients with an inflammatory or autoimmune disease presenting with acute onset of fever and respiratory symptoms were included. RESULTS A total of 123 patients were included, of whom 42% had confirmed PCP, 18% had possible PCP, and 40% were negative for PCP. Immunosuppressive conditions consisted mostly of diffuse connective tissue disease (50%) and primary nephropathy (20%). Immunosuppressive therapies consisted of corticosteroids (95%) with concomitant non-steroidal drugs (80%). Independent predictors of PCP were a CD3+ cell count <625×106/l, serum albumin <28g/l, and PaO2/FiO2 <210. Furthermore, 90% of patients with PCP had a CD3+ cell count <750×106/l. Independent predictors of mortality were a CD8+ cell count <160×106/l and a PaO2/FiO2 <160. CONCLUSIONS In patients with inflammatory and autoimmune conditions receiving immunosuppressive therapy, low CD3+ and CD8+ cell counts were strongly associated with PCP and its mortality. These results suggest that lymphocyte subtyping is a very useful tool to optimize the selection of patients needing prophylaxis.

Severe adenovirus community-acquired pneumonia in immunocompetent adults: chest radiographic and CT findings

BACKGROUND Severe adenovirus pneumonia and its associated imaging features are well-described in immunocompromised patients but are rare and poorly understood in immunocompetent adults. We sought to describe the radiographic and CT findings of severe adenovirus community-acquired pneumonia (CAP) in eight immunocompetent adults. METHODS We reviewed systematically chest imaging manifestations of laboratory-confirmed severe adenovirus pneumonia in eight immunocompetent adults from April 2012 to April 2014. RESULTS All patients showed abnormal results on initial chest radiograph and CT, with the exception of one normal initial chest radiograph. The abnormalities of the initial chest radiographs were unilateral (n=4) or bilateral (n=3), including consolidation (n=4), dense patchy opacity (n=3), ground glass opacity (GGO) (n=1), and pleural effusion (n=1). The initial CT findings consisted of unilateral (n=5) and bilateral (n=3) abnormalities, including consolidation (n=8), GGO (n=2), pleural effusion (n=3) and small nodules (n=1). Focal consolidation was the predominant finding in six patients whose initial CT scans were examined within one week after illness onset. Follow-up radiologic findings showed rapid development of bilateral consolidation within ten days after illness onset, usually accompanied by adjacent ground-glass opacity and pleural effusion. The parenchymal abnormalities began to absorb around two weeks after illness onset, with no appearances of fibrosis. CONCLUSIONS Severe adenovirus CAP in immunocompetent adults mainly appears as focal consolidation followed by rapid progression to bilateral consolidation, usually accompanied by adjacent GGO and pleural effusion, which may resemble bacterial pneumonia. Adenovirus should be considered in severe pneumonia cases with negative cultures and failure to respond to antibiotics.

Why do not we use finger pulse oximeter plethysmograph waveform to monitor the effectiveness of cardiopulmonary resuscitation

Both the European Resuscitation Council (ERC) and the Amerian Heart Association (AHA) 2010 guidelines for cardiopulmonary esuscitation (CPR) once again emphasize the need for high quality PR, including a compression rate of at least 100 min−1.1 Quanitative waveform capnography is recommended as a physiologic onitor of the effectiveness of chest compressions in the new uidelines. Quantitative waveform capnography is not available in most PR situations and it has to be calibrated, which is time-consuming. ulse oximetry is much more commonly available. Recent studies how the pulse oximeter plethysmographic waveform can be used s an early indication of changes in the circulation.2 Why do not we se a finger pulse oximeter plethysmograph waveform to monitor ffectiveness of resuscitation efforts during CPR? The pulse oximeter provides a rapid, noninvasive, and continous measurement of arterial oxygen saturation that has become uniform standard for patient monitoring throughout medicine. ulse oximeters often show the pulsatile change in absorbance n a graphical form – the plethysmograph. The plethysmograph aveform is similar in appearance to an arterial blood presure waveform. Although the plethysmograph is not a direct nalogue of arterial pressure or cardiac output, its waveform is elated to general haemodynamic status and peripheral tissue erfusion, so it can provide useful information about the cariovascular system. Because the pulse oximeter is noninvasive nd ubiquitous in hospitals, it is logical to seek circulatory inforation from the plethysmograph waveform. The extraction of irculatory information from the plethysmographic waveform has een well researched. The plethysmograph waveform may provide nformation related to hypotension, hypovolaemia, low cardiac utput, vasoconstriction and other circulatory conditions.2,3 During PR time is limited; it is difficult to establish invasive haemodyamic monitoring to assess the quality of CPR. The pulse oximetry lethysmograph waveform can be used to monitor adequacy of nterventions. In our clinical practice, high quality chest compresions often produce excellent pulse oximetry tracings in patients ith a lack of spontaneous circulation. During CPR, the plethysograph may indicate the presence or absence of measurable erfusion with each chest compression. Since the plethysmograph isplays a pulsatile waveform, it can used also to monitor chest

miRNA-200c-3p is crucial in acute respiratory distress syndrome.

Influenza infection and pneumonia are known to cause much of their mortality by inducing acute respiratory distress syndrome (ARDS), which is the most severe form of acute lung injury (ALI). Angiotensin-converting enzyme 2 (ACE2), which is a negative regulator of angiotensin II in the renin–angiotensin system, has been reported to have a crucial role in ALI. Downregulation of ACE2 is always associated with the ALI or ARDS induced by avian influenza virus, severe acute respiratory syndrome-coronavirus, respiratory syncytial virus and sepsis. However, the molecular mechanism of the decreased expression of ACE2 in ALI is unclear. Here we show that avian influenza virus H5N1 induced the upregulation of miR-200c-3p, which was then demonstrated to target the 3′-untranslated region of ACE2. Then, we found that nonstructural protein 1 and viral RNA of H5N1 contributed to the induction of miR-200c-3p during viral infection. Additionally, the synthetic analog of viral double-stranded RNA (poly (I:C)), bacterial lipopolysaccharide and lipoteichoic acid can all markedly increase the expression of miR-200c-3p in a nuclear factor-κB-dependent manner. Furthermore, markedly elevated plasma levels of miR-200c-3p were observed in severe pneumonia patients. The inhibition of miR-200c-3p ameliorated the ALI induced by H5N1 virus infection in vivo, indicating a potential therapeutic target. Therefore, we identify a shared mechanism of viral and bacterial lung infection-induced ALI/ARDS via nuclear factor-κB-dependent upregulation of miR-200c-3p to reduce ACE2 levels, which leads increased angiotensin II levels and subsequently causes lung injury.

Airway compromise in a special situation—relapsing polychondritis

A 36-year-old female was presented to our emergency department with 1-day history of shortness of breath. She had complained of a 6-month history of gradually increasing wheeze, intermittent fever and productive cough. She had sought help in her local community hospital but no diagnosis was reached. On examination she had wheezing in both lungs. After admission the patient soon developed drowsiness and then coma. Arterial blood gas analysis revealed pH: 7.15, PaCO2: 102 mmHg and PaO2: 134 mmHg. Rapid sequence intubation and …

Comparison of different inspiratory triggering settings in automated ventilators during cardiopulmonary resuscitation in a porcine model

Background Mechanical ventilation via automated in-hospital ventilators is quite common during cardiopulmonary resuscitation. It is not known whether different inspiratory triggering sensitivity settings of ordinary ventilators have different effects on actual ventilation, gas exchange and hemodynamics during resuscitation. Methods 18 pigs enrolled in this study were anaesthetized and intubated. Continuous chest compressions and mechanical ventilation (volume-controlled mode, 100% O2, respiratory rate 10/min, and tidal volumes 10ml/kg) were performed after 3 minutes of ventricular fibrillation. Group trig-4, trig-10 and trig-20 (six pigs each) were characterized by triggering sensitivities of 4, 10 and 20 (cmH2O for pressure-triggering and L/min for flow-triggering), respectively. Additionally, each pig in each group was mechanically ventilated using three types of inspiratory triggering (pressure-triggering, flow-triggering and turned-off triggering) of 5 minutes duration each, and each animal matched with one of six random assortments of the three different triggering settings. Blood gas samples, respiratory and hemodynamic parameters for each period were all collected and analyzed. Results In each group, significantly lower actual respiratory rate, minute ventilation volume, mean airway pressure, arterial pH, PaO2, and higher end-tidal carbon dioxide, aortic blood pressure, coronary perfusion pressure, PaCO2 and venous oxygen saturation were observed in the ventilation periods with a turned-off triggering setting compared to those with pressure- or flow- triggering (all P<0.05), except when compared with pressure-triggering of 20 cmH2O (respiratory rate 10.5[10/11.3]/min vs 12.5[10.8/13.3]/min, P = 0.07; coronary perfusion pressure 30.3[24.5/31.6] mmHg vs 27.4[23.7/29] mmHg, P = 0.173; venous oxygen saturation 46.5[32/56.8]% vs 41.5[33.5/48.5]%, P = 0.575). Conclusions Ventilation with pressure- or flow-triggering tends to induce hyperventilation and deteriorating gas exchange and hemodynamics during CPR. A turned-off patient triggering or a pressure-triggering of 20 cmH2O is preferred for ventilation when an ordinary inpatient hospital ventilator is used during resuscitation.

Influence of Chest Compressions on Circulation during the Peri-Cardiac Arrest Period in Porcine Models.

Objective Starting chest compressions immediately after a defibrillation shock might be harmful, if the victim already had a return of spontaneous circulation (ROSC) and yet was still being subjected to external compressions at the same time. The objective of this study was to study the influence of chest compressions on circulation during the peri-cardiac arrest period. Design Prospective, randomized controlled study. Setting Animal experimental center in Peking Union Medical Collage Hospital, Beijing, China. Subjects Healthy 3-month-old male domestic pigs. Interventions 44 pigs (28±2 kg) were randomly assigned to three groups: Group I (non-arrested with compressions) (n = 12); Group II (arrested with compressions only) (n = 12); Group III (ROSC after compressions and defibrillation) (n = 20). In Groups I and II, compressions were performed to a depth of 5cm (Ia and IIa, n = 6) or a depth of 3cm (Ib and IIb, n = 6) respectively, while in Group III, the animals which had just achieved ROSC (n = 18) were compressed to a depth of 5cm (IIIa, n = 6), a depth of 3cm (IIIb, n = 6), or had no compressions (IIIc, n = 6). Hemodynamic parameters were collected and analyzed. Measurements and Findings Hemodynamics were statistically different between Groups Ia and Ib when different depths of compressions were performed (p < 0.05). In Group II, compressions were beneficial and hemodynamics correlated with the depth of compressions (p < 0.05). In Group III, compressions that continued after ROSC produced a reduction in arterial pressure (p < 0.05). Conclusions Chest compressions might be detrimental to hemodynamics in the early post-ROSC stage. The deeper the compressions were, the better the effect on hemodynamics during cardiac arrest, but the worse the effect on hemodynamics after ROSC.

Transesophageal echocardiography to assess mitral valve movement and flow during long term cardiopulmonary resuscitation: How cardiac effects fade with time

BACKGROUND Although the cardiac pump and the thoracic pump are the two main theories, the actual mechanisms of blood flow during Cardiopulmonary Resuscitation (CPR) in humans are still unclear. The aim of this study was to explore the relationship between the pump mechanism and time after cardiac arrest. METHODS AND RESULTS 20 patients with non-traumatic cardiac arrest were enrolled in this study. Transesophageal two-dimensional and pulse-doppler echocardiography were used during CPR. The duration of CPR was 60-80min if there was no return of spontaneous circulation (ROSC). We found: (1) The mechanisms of blood flow during CPR varied with time: the thoracic pump took the place of the cardiac pump after prolonged CPR in the same patient. (2) Peak transmitral flow (TMF) decreased (p<0.05) after prolonged CPR in patients with mitral valve closure during chest compressions. (3) Longer elapsed time from collapse to CPR and TEE was correlated to lower peak TMF in CPR (Both p<0.05). (4) Peak TMF(p<0.01), mitral valve time-velocity integrals(p<0.05), left ventricular stroke volume (p<0.05) and end-tidal carbon dioxide tension (p<0.05) is higher in the group of patients with mitral valve closure during chest compressions. This group of patients had a shorter time from collapse to CPR (p<0.01), shorter time from collapse to TEE (p<0.01) and had overall better outcomes. CONCLUSIONS The pump mechanism changes over the course of prolonged CPR. Cardiac effect is an essential part of the pump at the beginning of cardiac arrest, but it faded with time, making the thoracic pump the dominate mechanism after prolonged CPR.

Aortic dissection associated with right pulmonary artery compression

A 48-year-old man presented with a 3-day history of increasing central chest pain and dyspnoea. He had a 5-year history of hypertension that was not controlled by any medication. On examination, blood pressure was 201/125 mm Hg, oxygen saturation was 90% on air, heart sounds were normal, and the chest was clear on auscultation. ECG showed extensive T wave inversion in the anterior leads. Blood tests revealed the …