The current epidemiological situation
General facts on COVID-19
Since January 2020, the COVID-19 pandemic has spread rapidly worldwide. According to the World Health Organization (WHO) up to now 3,759,967 COVID-19 cases have been confirmed worldwide and 259,474 patients have already died .
Epidemiological information on and study results from COVID-19 must still be interpreted with caution. They are subject to powerful dynamics and multifactorial influences, display a variable data quality and due to differences in healthcare structures and epidemiological features allow only limited international comparisons. Therefore, as is common practice in antibiotic stewardship, national and regional data should be systematically gathered and regularly analyzed. This is the only way in which the current local situation can be adequately assessed.
Like influenza, COVID-19 is a viral infectious disease with a variable course (from asymptomatic to mild to severe to fatal). In Europe, most of the people positively tested show mild symptoms. Conversely, more than 80% of the hospitalized patients suffered from fever, cough and respiratory distress (Table 1; [2, 3]). In particular, older and comorbid patients are severely affected and present with severe community acquired pneumonia (CAP) with resulting hypoxia. In addition, possible COVID-19 specific phenomena are described, such as a reduced sensation of dyspnea, whereby a respiratory deterioration may not be subjectively perceived for a long time, a lack of increase of the respiratory rate despite severe oxygenation disturbance, and a temporary loss of smell and taste.
Due to the infectiousness of the pathogen, hospital-associated SARS-CoV‑2 pneumonia can also be expected in the future.
According to the European Centre for Disease Prevention and Control (ECDC), severe COVID-19 courses (need for hospitalization) have so far been observed in Europe in 28% of all cases; however, due to undetected mild courses, a high number of unreported cases and a higher rate of mild courses can be assumed.
An average of 16% of hospitalized patients suffered from a very serious illness course (need for intensive care or respiratory support) and COVID-19 hospital mortality in Europe is currently at 14% .
There are relevant differences in Europe with respect to COVID-19 deaths per 100,000 inhabitants. With a comparable COVID-19 incidence (175–250 cases/100,000 inhabitants), 7–9 deaths/100,000 have been registered in Austria, Denmark, Germany, and Liechtenstein and 31–39 deaths/100,000 in France, Sweden, and the Netherlands . In Europe, the highest burden of COVID-19 is currently reported from Belgium (455 cases/100,000 and 75 deaths/100,000 inhabitants). In line with these figures, the European monitoring of excess mortality for public health action (EuroMOMO) network has recorded an exceptionally high pandemic-associated excess mortality rate in certain European countries (UK, France, Spain, Belgium, the Netherlands, Italy, and Switzerland), but a significantly lower one in Austria and other countries, such as Denmark, Germany, Greece, Norway, and Ireland .
In Austria, 15,735 persons have so far been tested positive for SARS-CoV‑2 and 615 (3.9%) have died from or with COVID-19. At present, 230 COVID-19 patients are hospitalized (peak at the beginning of March with 1010 hospitalized patients) and 79 are being treated in intensive care units (peak at the beginning of March with 267 ICU patients) (24–34% more than the European average). Thus, at the beginning of March 26% (currently only 8%) of all available intensive care beds in Austria were occupied by COVID-19 patients . Primary data on the number of patients previously treated in hospitals or intensive care units and the mortality rates are currently unavailable in Austria.
Hospitalization and mortality risk for COVID-19 and community-acquired pneumonia due to other pathogens
In order to realistically classify the current COVID-19 data, they must also be compared with the incidence and course of other severe respiratory infections as they occurred before the COVID-19 pandemic. In principle, pathogen-induced CAP which requires hospitalization (hCAP) is frequent. With an incidence of 296 hCAP per 100,000 inhabitants, an estimated 26,222 patients with hCAP are treated in Austria every year and 2185 patients every month . With an average hospital mortality rate of 13% (Table 2) Austria has 3409 (39/100,000) hCAP deaths per year and 284 hCAP deaths per month whereas COVID-19 caused 491 deaths per month during the peak phase of the pandemic (27 March–27 April 2020). It can therefore be assumed that in Austria the pandemic caused at least a transient doubling of hCAP deaths/100,000 inhabitants.
Influenza must be considered separately as the influenza case fatality rate is only partly caused by influenza pneumonia but 400,000 influenza-associated deaths are annually expected worldwide [8, 9].
The incidence of inpatient influenza cases in Europe ranges between 12–95/100,000 depending on the season of the year and the effective vaccination coverage rate of the population, and for children in Austria between 2002 and 2018 was 50/100,000 [10,11,12,13]. If this incidence is applied to Austria, assuming an ICU rate of 7% and a hospital mortality rate of 4%, during each influenza season there will be 1152–8416 inpatients, 81–589 cases requiring ICU, and 46–337 inpatient deaths in Austria. For the period from December to April (influenza season), for Austria this means that there are 288–2104 inpatients and 20–147 influenza cases requiring ICU per month. Due to a very low influenza vaccination rate as compared to other European countries, higher rather than lower rates can be expected for Austria. This assumption is supported by calculations of the Agentur für Gesundheit und Ernährungssicherheit (AGES), which based on the statistical model FluMOMO, supposes an average of 2326 influenza deaths per year in the last 4 years and thus 582 influenza deaths per month during the influenza season (COVID-19: currently approximately 450 deaths per month, as of 19 April 2020) . Accordingly, the annual wave of influenza in Austria is very likely to lead to a burden on the healthcare system comparable to that of the current COVID-19 pandemic. Therefore, systematic recording like that currently established for COVID-19 should also be introduced in Austria with respect to influenza-associated deaths amongst hospitalized patients.
To sum up, it can be assumed that SARS-CoV‑2 can be listed as another relevant CAP pathogen that for an unforeseeable period of time will significantly increase the incidence of CAP, especially amongst older people, and similarly to influenza infections involves significant logistical and hospital hygiene and infection prevention efforts. Due to the governmental preventive measures both inside and outside the healthcare system, the COVID-19 pandemic in Austria has so far been successfully contained but a further increase in COVID-19 cases is possible following the easing of the lockdown restrictions. As far as can be currently assessed, the hospitalization rate for SARS-CoV‑2 CAP seems to be higher than that for CAP due to other pathogens, and depending on the functionality of the healthcare system hospital mortality would appear to be comparable to that of other pathogen-induced CAP (Table 2).
The CAP mortality risk is determined by the extent of immediate lung parenchyma damage, secondary infections/complications, age and pre-existing comorbidities, and the quality of the available medical care. The significance of typical cardiopulmonary, renal and metabolic comorbidities for the course of CAP is well-known from influenza, pneumococcal and legionella infections, and plays a decisive role in SARS-CoV‑2 CAP to the same extent. Consequently, as is the case with other CAP pathogens, the risks of hospitalization and mortality of SARS-CoV‑2 CAP increase significantly from the age of 60 years and with the number of concomitant diseases (Table 3; [7, 10, 15, 29, 41]).
Furthermore, the COVID-19 pandemic has clearly demonstrated that the mortality rate of an acute infection is always determined by social and structural factors (e.g. timely public health interventions to slow the spread of a pandemic infection, prompt and flexible structural adjustments to the healthcare system, the number of immediately available intensive care or mechanical ventilation beds, capacity for isolation and protection in the outpatient and inpatient area, short-term and effective medical staff training).
In some countries and regions there were acute supply emergencies and therefore it can be assumed that in these critical and partly catastrophic medical situations, not all acutely and severely ill patients could be provided with the required timely and adequate medical care. For example, the mortality rate in the primarily unprepared epicenter (Wuhan city in Hubei province) was initially 12% and later in the other Chinese provinces only about 1% . This is substantiated by excess mortality rates recorded by EuroMOMO in some countries that were severely affected by the pandemic.
SARS-CoV-2 in children
In an analysis of the first approximately 45,000 laboratory-confirmed COVID-19 cases in China, children <10 years of age represented only 0.9% (416 children) and children between 10 and 19 years of age only 1.2% (549 children) of the cases . Until now, neonatal COVID-19 cases have been extremely rare ; however, the number of children, who are actually infected, but have not been tested due to missing or mild symptoms, still remains unclear. Close contact with a SARS-CoV‑2 infected person in the family environment seems to be the most frequent transmission route .
As compared to adults, children and adolescents are much less likely to fall ill from SARS-CoV‑2 and have often shown only mild clinical symptoms. Only one quarter developed temperatures between 38 and 39 °C, and only 10% temperatures >39.0 °C. Coughing and tachypnea are described in about 30–50% and pharyngitis (5–45%), rhinitis (10–30%), diarrhea (10–30%) and vomiting (6%) are significantly less frequent [48,49,50,51]. Similarly to adults, laboratory tests showed an increase in C-reactive protein (CRP) (moderate), transaminases, lactate dehydrogenase, D‑dimer and creatine kinase, as well as leukopenia (primarily lymphopenia) .
Due to the less specific symptoms in children, it is difficult to make a reliable clinical diagnosis. Accordingly, especially in pediatric patients it is important to test extensively for SARS-CoV‑2 and to implement appropriate protective measures for medical personnel.
Severe courses of respiratory insufficiency, or the need for intensive care constitute the exception . Severe COVID-19 infections have been repeatedly suspected in infants; however, these were mostly only suspected cases (without SARS-CoV‑2 testing). The authors assume that other viruses (especially respiratory syncytial virus [RSV]) might have caused a considerable percentage of the severe courses of the infection . Only a few pediatric COVID-19 deaths have been reported in the literature so far [46, 47, 53].
Due to the often milder disease course in children, it has been discussed whether oligosymptomatic and asymptomatic children could play an essential role in the transmission, without this hypothesis ever having been confirmed scientifically . On the contrary, a recent study from Iceland showed that when screening asymptomatic individuals, the proportion of virus excretion is threefold higher in 40–50 year-olds (approx. 1.5%) than in children/young people between the ages of 10 and 20 years (approx. 0.5%). In a group of more than 800 children under 10 years of age, not a single child was tested positive .
The SARS-CoV‑2 infections in children with risk factors and underlying diseases (chronic respiratory diseases such as cystic fibrosis, severe asthma, bronchopulmonary dysplasia as well as cardiac diseases, primary and secondary immunodeficiencies, underlying malignant diseases, malnutrition, etc.) are rarely reported in pediatric analyses [46, 52]. Whether or not it can be derived that these children are less at risk than adults with risk factors, or whether children from risk groups have more effectively been protected against infection, remains unclear.
As soon as the governmental pandemic prevention measures are eased, the Austrian healthcare system must be further prepared for more than a renewed increase in the number of COVID-19 cases. All other respiratory infections (e.g. influenza, RSV, Pneumococcus, Mycoplasma and Bordetella infections), the spread of which as in the case of SARS-CoV‑2 was concomitantly suppressed by the pandemic prevention measures, will also increase again.
Within this context, the increased public awareness of potentially threatening infectious diseases created by the COVID-19 pandemic is to be welcomed. As a next step, targeted reasonable, individual and social preventive measures have to be developed and supported. For example, these could not only include the individual willingness for protective vaccination against influenza and other relevant pathogens but also a deeper understanding among the population of how to autonomously differentiate between harmless infections that should be cured at home and serious acute illnesses that must be treated by a general practitioner or in hospital (Fig. 1).
Management of SARS-CoV-2 pneumonia
Basic management of SARS-CoV-2 CAP
Serious SARS-CoV‑2 pneumonia is a severe viral CAP (svCAP), the clinical presentation of which (acute onset, bilateral pneumonia, progressive respiratory failure, high risk of mortality) is comparable to that of severe influenza CAP (Table 2). In the current pandemic situation, the guarantee of sufficient medical care for such severe medical conditions is of crucial importance. Due to the frequency of svCAP (especially during the annual influenza season), the medical centers in Austria are familiar with the clinical management of svCAP.
As the functionality of the Austrian healthcare system was not significantly impaired during the current COVID-19 pandemic, the key points of current evidence-based guidelines for the treatment of CAP should also be applied to SARS-CoV‑2 CAP and serve as general orientation (Figs. 1, 2 and 3):
Early diagnosis of CAP, possibly simultaneously decompensated underlying diseases and the recognition of life-threatening situations
Start of CAP therapy without delay (including the treatment of respiratory insufficiency, hemodynamic instability, decompensated underlying diseases and, if indicated, anti-infective therapy)
Triage according to the clinical findings (outpatient vs. inpatient vs. intensive care treatment)
Definition of appropriate treatment goals and avoidance of futile treatment in palliative patients already suffering from severe underlying diseases (see below)
From the outset, consequent adherence to strict hygiene measures for personal protection and the avoidance of nosocomial infections
Prevention of new infections
For details regarding guideline-based CAP diagnosis and therapy refer to current guidelines .
The key signs and symptoms of almost all respiratory tract infections are cough, possibly fever and dyspnea. This applies to any kind of bacterial or viral acute bronchitis, COPD exacerbation or pneumonia including COVID-19. Although COVID-19 is currently being diagnosed in hospitals to a larger extent, other acute cardiorespiratory diseases and infections are also present and will likewise increase again after the liberalization of the social pandemic measures. Therefore, CAP diagnostics that are exclusively focused on COVID-19 is unreasonable. In Austria CAP diagnostics should generally continue to follow the current recommendations from the German-Austrian-Swiss CAP guideline for adults from 2016 and for children and adolescents from 2017 [55, 56].
Nevertheless, within the context of the COVID-19 pandemic, diagnostic amendments for the early detection of a SARS-CoV‑2 infection in routine diagnostics are necessary (Figs. 1, 2 and 3):
Outpatients who are not seriously ill should contact the established contact points by telephone and seek information and advice on the current procedure (Fig. 1).
In patients with the clinical presentation of a possible respiratory tract infection without a clear etiological attribution, a SARS-CoV‑2 PCR should be performed in emergency rooms, or in hospitals if it is of therapeutic or hygienic relevance (Figs. 2 and 3).
A chest CT scan without contrast agent should be performed in patients in the emergency department or already hospitalized if a lower respiratory tract infection is suspected
the chest x‑ray is unremarkable (or difficult to interpret)
the rapid diagnostic tests for common infections (Influenza/RSV/SARS-CoV‑2 PCR, Pneumococcus/Legionella urine antigen test) are negative
typical laboratory values for COVID-19 (leucocytes <10.0 × 109/L, neutrophils <7.0 × 109/L, lymphocytes <1.0 × 109/L, CRP only moderately elevated (10–130 mg/L), procalcitonin <1.0 ng/mL [34, 37]) are present.
With typical COVID-19 CT findings, but a negative SARS-CoV‑2 PCR, the patient should first be classified as a suspected COVID-19, and other differential diagnoses proactively evaluated and the SARS-CoV‑2 PCR repeated.
A positive SARS-CoV‑2 PCR confirms the diagnosis of COVID-19. The sensitivity of a virus-specific PCR is dependent on multiple factors, such as the time of testing (at the start of infection versus a later time point), the sample material (oropharyngeal swab versus nasopharyngeal swab versus sputum or bronchial lavage), the sample quality and the applied test procedure (type of assay). Therefore, a negative PCR result does not exclude COVID-19 if the clinical presentation and the CT findings are typical. The SARS-CoV‑2 PCR from sputum samples or bronchial lavage fluids are in general more sensitive than those from nasopharyngeal smears ; however, for reasons of hygiene neither sputum induction nor diagnostic bronchoscopy should be solely performed for confirming COVID-19. In intubated patients with an initially negative PCR from the upper respiratory tract, further PCR testing in a lower respiratory tract specimen (e.g. tracheal secretions via closed suction system) is recommended. This increases the diagnostic sensitivity and reduces the false negative test rate [58, 59].
A chest x‑ray is neither sufficiently sensitive nor precise enough for the diagnosis of SARS-CoV‑2 CAP; however, if the clinical signs and symptoms are specific and the PCR result is positive, x‑ray findings typical for COVID-19 (bilateral mostly ground glass-like peripheral and basal consolidations) are sufficient.
In justified cases (as mentioned), severe cases, or for better differentiation of alternative diagnoses or complications, a chest CT scan is indicated . Typical COVID-19 chest CT findings are bilateral, multifocal, peripheral/subpleural and dorsobasal ground glass opacities with or without consolidations. In the course of the disease, consolidation areas may increase and a crazy paving pattern may occur. Sensitivity, specificity, negative and positive predictive values of chest CT scans were described in a larger study as 97%, 25%, 65% and 83%, respectively . Thus, SARS-CoV‑2 CAP can be detected sensitively by chest CT, but the radiological changes may also result from other infections or diseases, or complications.
Specific SARS-CoV-2 CAP therapy
In general, treatment of a SARS-CoV‑2 CAP, as of another bacterial or viral pneumonia, should follow relevant guidelines (see above). Currently, there is broad discussion about antiviral and anti-inflammatory treatment approaches that have yet to be sufficiently validated (remdesivir, chloroquine, hydroxychloroquine, tocilizumab, recombinant angiotensin converting enzyme 2 and others). They should therefore not be used as standard therapy in clinical routine. According to the WHO recommendations, their efficacy, safety and tolerability should first be tested in clinical trials, preferably randomized controlled trials (RCT) [62, 63]. Until results from RCTs are available, experimental therapies outside clinical trials must be extremely well justified and considered solely in selected individual cases (compassionate use). They should not be used uncritically, potentially harmful side effects must be considered and wherever possible, their application should be documented in registers .
On 28 March 2020, the U.S. Food and Drug Administration (FDA) issued an emergency use authorization for chloroquine/hydroxychloroquine, and on 1 May 2020 for remdesivir for the treatment of COVID-19 . The FDA points out that only in vitro or anecdotal clinical data and case series on the efficacy of chloroquine and hydroxychloroquine are available and that these drugs should be further tested in RCTs. Nevertheless, the FDA has approved the use of chloroquine and hydroxychloroquine for hospitalized COVID-19 patients (body weight >50 kg) outside of studies. For remdesevir, the FDA decision was based on unpublished topline data from a randomized, double-blind, placebo-controlled trial (NCT04280705) and from another open-label trial (NCT04292899). At present, the European Medicines Agency (EMA) has not granted approval for chloroquine, hydroxychloroquine, remdesivir or any other specific SARS-CoV‑2 therapy or vaccination.
With a few exceptions, a large number of studies and meta-analyses showed no benefit and even an increased fatality rate for systemic steroids in svCAP or viral acute respiratory distress syndrome (vARDS) [66,67,68]. Accordingly, the routine use of systemic steroids for the treatment of svCAP/vARDS including COVID-19 is not recommended ; however, in exceptional circumstances, systemic steroids may be considered in cases of viral CAP:
According to the septicemia guidelines, hydrocortisone is indicated for refractory shock with massive hemodynamic instability [69, 70].
Severe COPD exacerbation: 0.5 mg prednisolone/kg/day for 5–7 days, then stop.
Severe asthma exacerbation: 0.5 mg prednisolone/kg/day for a maximum of 7 days, then slowly tapering over a further 7 days.
In the course of svCAP, systemic steroids may be considered in suspected individual cases of organizing pneumonia, postpneumonic interstitial pneumonia, hemophagocytic lymphohistiocytosis, or exacerbation of pre-existing pulmonary fibrosis.
Respiratory intensive care
Patients requiring intensive care and ventilation should be treated according to generally accepted national and international recommendations. Thus, for the usually predominant severe oxygenation disorder, an escalation from a ventilation mask with reservoir (non-rebreather mask) via high-flow nasal oxygenation (HFNO) to non-invasive ventilation (NIV) is recommended. In all international recommendations, special focus is placed on the protection of the practitioner, in particular during measures such as intubation, NIV, HFNO, bronchoscopy or nebulization [69, 71, 72]. Aerosol production is probably not significantly increased with oxygen therapy, HFNO, nebulization and NIV with non-vented systems, and a significantly increased risk for personnel is presently not assumed. In contrast, an increased risk for personnel has been shown for intubation, bronchoscopy, endotracheal aspiration and the use of vented systems, or in the absence of a virus filter in the expiratory part of ventilation systems. A recent COVID-19 position paper of the German Respiratory Society provided a good overview of aerosol production and the resultant risk for practitioners .
If available, HFNO and NIV of COVID-19 patients should be performed in negative pressure rooms. In clinical practice, however, the number of negative pressure rooms is limited in Austria, and HFNO and NIV are also acceptable in other facilities; however, personal protection measures must be strictly adhered to.
Since aerosol formation increases with augmented HFNO flow rate, the flow rate should be set as low as possible and an oronasal mask (FFP1 mask) should be applied to the patient’s face to reduce aerosol release. In general, intensified monitoring should be ensured in patients with very high or rapidly progressive oxygen demand because acute respiratory failure requiring immediate intubation must be identified without delay.
Irrespective of the type of ventilation, the use of a respirator with a double-hose system and bacteria/virus filter at the expiratory section of the breathing circuit is recommended. Ventilation with a single-hose system and vented systems should be avoided due to aerosol formation. Ventilators for home ventilation, including obstructive sleep apnoea syndrome (OSAS) therapy, should therefore not be used in the inpatient setting for SARS-CoV‑2 positive patients, but should be replaced by suitable ventilators, or an appropriate mask construction with a filter at the expiratory valve. Air humidifiers of home ventilators should not be used . If only ventilators with a single-hose system and distal flow measurement are available, a filter must be installed at the patient side, with the resultant increase in airway resistance to be taken into account. If a continuous positive airway pressure (CPAP) helmet is used, a filter must be attached to the expiratory part.
For intubation, video laryngoscopy and rapid sequence induction with full relaxation are recommended to prevent aerosol formation, possible coughing of the patient and close proximity of the airway operator to the patient’s head. Nebulization should be avoided in favor of the use of metered dose inhalers.
According to the severity of the oxygenation impairment, intubation and invasive ventilation are often recommended for an oxygenation index (PaO2/FiO2) ≤200 . Whether in such a case NIV is still feasible as an alternative has to be individually assessed for each patient. Depending on the underlying pulmonary disease and the clinical condition, with special regard to the load of the respiratory muscles, the cooperation of the patient, strict protective measures for the medical staff, and the user’s experience with NIV are particularly important. In the presence of ARDS and no improvement with NIV, intubation should not be delayed.
Two phenotypes of COVID-19 lung disease are distinguished (Fig. 4): the L‑type (low elastance) is characterized by good compliance, a poor response to recruitment maneuvers and deterioration when excessively high positive end-expiratory pressure (PEEP) is used (>10 cm H2O). The frequent severe oxygenation impairment is primarily due to vasoplegia with an altered ventilation-perfusion ratio and microthrombotic events.
In the L‑type, O2/HFNO application, NIV or invasive ventilation with lower PEEP (6–10 cm H2O) and prone positioning are usually effective. Higher tidal volumes are well tolerated without lung injury (ventilator induced lung injury, VILI).
The H‑type (high elastance) is characterized by poor compliance (<40 ml/cm H2O), a higher shunt, increased right cardiac pressure and a better response to recruitment maneuvers, and basically represents full-blown severe ARDS. Mechanical ventilation with a relatively high PEEP (invasively mostly >15 cm H2O), but frequently low plateau pressures is useful. It can be assumed that COVID-19 ARDS patients also benefit significantly from prone positioning according to the ProSEVA protocol [62, 75]. Recruitment maneuvers (Lachmann maneuvers) can also be tried in patients with the H‑type .
A transition from the L‑type to the H‑type is possible and may be recognized early due to increased breathing effort (esophageal manometry, change in CVP, assessment of the work of breathing).
According to present experience and autopsy reports, euvolemia is recommended because overhydration disproportionately worsens the respiratory situation.
To date, there is no substantial evidence for the application of the aforementioned experimental COVID-19 therapies for patients in intensive care. Based on the principle primum nil nocere, the use of insufficiently validated and unapproved medications is only recommended in clinical trials, or in compassionate use programs. Moreover, potential side effects and possible interactions with standard intensive care medication have to be considered . Equally, the evidence for efficacy of a supportive therapy with zinc, ascorbic acid or selenium is also insufficient.
The WHO guidelines for the treatment of COVID-19 incorporate the subject of intensive care and we recommend the regular updates to be followed and accounted for .
Microcirculatory disturbances on a thrombotic basis are assumed, and after a risk-benefit analysis a pharmacologic thrombosis prophylaxis is also indicated for the frequently occurring (moderate) thrombocytopenia [78, 79].
As occurs during other serious infections, COVID-19 ARDS patients may develop a form of secondary hemophagocytic lymphohistiocytosis (sHLH). Therefore, a close watch must be kept for signs of a massive hyperinflammatory response. Specific and adequately evaluated diagnostic criteria for COVID-19 sHLH are not yet available [80, 81]. Diagnosis and classification of sHLH so far have been based on the practice-oriented and evaluated HScore [82, 83]. A freely available calculator can be found at http://saintantoine.aphp.fr/score/. There is no gold standard for the therapy of sHLH; the current evidence is based on case series, and RCTs have yet to be conducted. As with other non-COVID-19 associated sHLH, in individual cases especially systemic corticosteroids, but also cyclosporine, intravenous immunoglobulins, anakinra, tocilizumab or other therapies may be considered .
During any form of inhalation or respiratory support therapy (nebulization, O2 via nasal cannula/mask, HFNO, NIV), aerosol formation and thus an increased risk of infection for healthcare professionals and patients must be expected (see also section on “Cardiorespiratory physiotherapy”) . These treatment forms should only be used if indicated, and in view of the possible risk of contamination of the surroundings by aerosols should either be applied in a relatively restrictive manner or even avoided. Preferably, bronchodilators or corticosteroids should be inhaled with dry powder inhalers or (also with NIV or invasive ventilation) metered dose inhalers .
For further details see the sections on “Respiratory intensive care” and “Cardiorespiratory physiotherapy”.
Hospitalized COVID-19 patients with sleep-related breathing disorders
If a patient treated with positive airway pressure (PAP) for a sleep-related breathing disorder develops COVID-19, it may be assumed that analogous to NIV and aerosol therapy, this therapy increases virus transmission to the environment. In this case, an individual risk-benefit assessment must be performed; however, if possible, PAP should be continued under strict hygiene and isolation measures. According to current evidence, PAP does not exacerbate COVID 19 infections. When single-hose systems and vented masks have been used so far, for the protection of the practitioner it is recommended to not use air humidifiers if possible and change to non-vented masks with a special exhalation valve and filter. If available, switching to a two-hose system is an alternative option.
Bronchoscopy in COVID-19 patients
Bronchoscopy is not recommended for the exclusion or verification of COVID-19 (lack of therapeutic consequence, unnecessary risk for personnel, and possible risk of clinical deterioration due to bronchoscopy); however, in exceptional situations, bronchoscopy may be indicated in confirmed or suspected COVID-19 patients (e.g. in immunosuppressed patients to exclude Pneumocystis pneumonia).
Bronchoscopy involves the risk of aerosol formation and thus a significantly increased risk of SARS-CoV‑2 infection for personnel present during the procedure. Bronchoscopy in intubated patients probably has a lower transmission risk.
In accordance with international recommendations, if SARS-CoV‑2 infection is suspected or confirmed, the following should be considered during the COVID-19 pandemic [87,88,89]:
Extremely restrictive indications for a bronchoscopy.
Primary use of other sensitive diagnostic procedures (e.g. obtaining tracheal secretions via a closed suction system for microbiological testing including SARS-CoV‑2 PCR).
Bronchoscopy is indicated in emergency situations (e.g. life-threatening hemoptoe, high-grade airway stenosis, or foreign body aspiration), or if an alternative diagnosis can be verified, which would lead to a significant change in therapeutic management.
Reduction of staff (bronchoscopist, bronchoscopy assistance, if necessary an anesthesia team) to a core team. No students, basic or advanced trainees in the bronchoscopy suite.
Strict personal protection for the entire team (disposable protective gown, disposable gloves, FFP3 mask, protective glasses/visor, hair protection). Strict attention to correctly putting on and taking off protective clothing.
If justifiable, rigid bronchoscopies with jet ventilation should not be performed; however, should a rigid bronchoscopy be unavoidable, it should be performed in an intubated patient with conventional ventilation and reduced aerosol escape, e.g. using a FLUVOG attachment (KARL STORZ SE & Co. KG, Tuttlingen, Germany).
Bronchial lavage should be performed as fractionated procedure (10 ml NaCl 0.9% for each fraction; to reduce the transmission risk, the suction device should be clamped after sampling or before disconnection).
Bronchoscopes are to be cleaned and disinfected in a validated manner; there is no evidence that these processes have to be changed for SARS-CoV‑2.
Routine bronchoscopies in non-COVID-19 patients (e.g. for the evaluation of pulmonary nodules/lesions or interstitial lung diseases) should only be performed during the current pandemic if strictly indicated, with increased personal protection measures (including the use of FFP2 or FFP3 masks) and strict adherence to hygiene protocols.
Therapeutic goals, treatment limitations and withdrawal of treatment in COVID-19 patients
The ethical principles of intensive and palliative care apply equally to COVID-19 patients. Since in several countries even increased intensive care resources have been completely exhausted, guidelines for the allocation of intensive care beds, triage and palliative care have been established in Austria [90, 91]. Based on the patient’s present state of health and the severity of the infection and respect for the will of the patient, capacities should be kept available for patients for whom a higher probability of survival is predicted . Not only is this a difficult undertaking due to the lack of validated predictive scores for COVID-19, but it also ignores the problem that patients without SARS-CoV‑2 infection, or those with clinically silent infection, may require intensive care for other reasons (e.g. COPD exacerbation, myocardial infarction, polytrauma, etc.) (Fig. 5). The German and British professional societies have developed recommendations regarding clinical-ethical decision-making [93, 94].