https://doi.org/10.1111/anae.15049 Extreme
measures have already been undertaken, including: closure of hospital
wards; restricting visitor access to hospital; identification of
external triage areas; dedicated patient transport and isolation
pathways; and cessation of elective surgery, with only emergency, trauma
and selected oncological surgery proceeding. Notably, operating rooms
are allocated as emergency critical care beds and anaesthetists have
been re‐allocated to critical care management and rapid response
emergency care, including dedicated COVID‐19 emergency teams to assist
patients in non‐critical care settings. In terms of public health,
several measures have been implemented, including: the use of
telemedicine consultations; domestic isolation of COVID‐19 patients who
are not severely unwell; production and distribution of educational
videos and television segments; and firm restrictions against public
gatherings. Most recently, much of northern Italy had a quarantine
imposed, affecting up to 16 million residents 19,
and on 11 March 2020, all Italian territories were identified as ‘red
zones’ by the Government, with firm restrictions on any public activity 20.
The acuity of the epidemic burden on healthcare
infrastructure has also led to the identification of certain hospitals
as ‘COVID‐19 sanatoriums,’ and we forecast a possible future of
‘COVID‐19 positive’ and ‘COVID‐19 negative’ hospitals. Finally, there
has been activation of military forces to construct field hospitals with
bio‐containment level resources. The role of anaesthetists and
intensivists has been critical, complex and dynamic. They have been
directly responsible for the early clinical management of critically ill
patients, and have faced the hardest task of undertaking critical,
ethically and psychologically disrupting triage, unavoidable though it
may be. To support clinicians with these ethical decisions, The Società
Italiana di Anestesia Analgesia Rianimazione e Terapia Intensiva
(SIAARTI) produced guidance on clinical management and triage during the
crisis 21.
Clinical management
Specific aspects of COVID‐19 patient care distinguish it from routine clinical practice (Table 2).
In these settings, there are factors that must be considered for:
oxygen administration and non‐invasive ventilation of the spontaneously
ventilating patient; airway management of the patient requiring tracheal
intubation; clinical management with PPE; and human factors
Table 2.
Clinical aspects of COVID‐19 patients during the
Italian outbreak. Preliminary observations based on data from Gruppo
Italiano per la Valutazione degli Interventi in Terapia Intensiva; http://giviti.marionegri.it)
Typical patient characteristics
Age
60–70 years
Sex
Male
Most common comorbidity
Obesity
Typical investigation findings
Procalcitonin
< 0.15 ng.ml−1 (normal)
Brain natriuretic peptide
< 100 pg.ml−1 (normal)
Creatine phosphokinase
Elevated, particularly in younger patients
Albumin
Reduced
Lymphocytes
Reduced
Chest X‐ray features
Bilateral interstitial pneumonitis
CT chest features
Parenchymal and interstitial involvement
Lung ultrasound
Diffuse B‐lines may indicate those who respond to high PEEP.
Anterior lung regions aerated or posterior atelectasis may indicate those who respond to prone positioning
Possible treatments and therapies
Antiretrovirals
Lopinavir or ritonavir
Other agents
Choroquine or hydroxychloroquine
Antibiotic prophylaxis
Piperacillin/tazobactam or ceftriazone or trimethoprim/sulfamethoxazole
Secretion management
N‐acetylecysteine
Other pharmacological agents
Corticosteroids or immune suppression, for example, tocilizumab
Sedation
Deep
Ventilation
Lung‐protective ventilation with high PEEP. Compliance is usually good.
Neuromuscular blockade
Deep, particularly during prone positioning
Fluid balance
Negative
Positioning
Consider up to seven cycles of prone positioning
Extracorporeal membrane oxygenation
Rarely used, but might be considered for those unresponsive to conventional ventilation
Renal replacement therapy
Challenging
COVID‐19, coronavirus disease 2019.
Oxygen administration
Given the aggressive pulmonary involvement associated
with COVID‐19, the requirement for non‐invasive or invasive oxygen
therapy is likely. All oxygen administration strategies in the
spontaneously ventilating patient carry risks of aerosolisation and
disease transmission. Hudson and Venturi masks, nasal cannulae and
helmets, carry a lower‐risk of transmission when compared with high‐flow
nasal oxygen and non‐invasive ventilation (NIV) with facemasks or hoods 22. Data from the SARS 23 and MERS 24
outbreaks cautioned against the use of high‐flow nasal oxygen or
non‐invasive ventilation, although this has recently been countered by
data demonstrating no increased dissemination of bacteria with high‐flow
nasal oxygen, yet viral spread remains unexplored 25.
As well as the potential risk of viral aerosolisation and the need for
careful isolation precautions, non‐invasive ventilation may also be
insufficient to manage COVID‐19‐induced respiratory failure, and
preliminary observations from the current Italian outbreak suggest there
may be a poor response to non‐invasive ventilation 3, 23, 25-27.
Delaying avoidable tracheal intubation may be beneficial 28, but delaying unavoidable tracheal intubation is a significant concern 27.
Invasive ventilation is associated with reduced aerosolisation and is
thus safer for staff and other patients. That said, it might also be
associated with hypoxia, haemodynamic failure and cardiac arrest 29, 30
during tracheal intubation, and a risk of staff exposure to high viral
load secretions, given that the very act of tracheal intubation is
associated with the greatest risk of exposure to healthcare
professionals 31.
Patient triage based on expected prognostic outcomes has become
increasingly important. Thus, early tracheal intubation is encouraged,
as late or emergency tracheal intubation in rapidly deteriorating
patients may be associated with greater risks, both to patients and
healthcare professionals.
Ethical burden and moral distress have been emerging
factors in the Italian outbreak, like that already seen in Wuhan.
Invasive ventilation must account for available personnel and critical
care beds, which have become rapidly saturated as our daily experience
is showing, with 650 COVID‐19 patients in critical care settings in
Italy on 8 March 2020 32.
Alternatives to tracheal intubation might reduce the demand on critical
care beds. Multidisciplinary evaluation, co‐operation and
decision‐making are strongly advised during this evolving and highly
dynamic crisis.
Airway management
Protocols and experiences in airway management for this and other coronavirus outbreaks 3, 23, 33-35,
as confirmed by our ongoing experience in Italy, is a necessity to
rigorously prepare for airway management. This includes utilisation of
cognitive aids such as checklists, cross‐checking and pre‐planned and
explicitly defined airway management strategies 36.
Any airway management procedure should be managed electively rather
than as an emergency, and any means to maximise first‐pass success
should be adopted. Procedures should be performed in a negative pressure
chamber (if available) or isolation area that is equipped with a
replenished, complete and checked emergency airway trolley. Entry and
departure of staff from the immediate clinical area must be strictly
monitored and restricted to those who are required. Thorough airway
assessment should guide clinicians to determine the safety of asleep
tracheal intubation, rather than awake tracheal intubation (ATI) 37, 38.
Clinicians must note that ATI is potentially a highly
aerosol‐generating procedure, thus the decision to undertake ATI must be
carefully considered.
Tracheal intubation
Patients with COVID‐19 are at risk of rapid arterial
oxygen desaturation, and therefore effective pre‐oxygenation is
mandatory. After pre‐emptive optimisation and correction of haemodynamic
disturbances, pre‐oxygenation with a fraction of inspired oxygen of 1.0
for at least 3 min at tidalvolume breathing or eight vital capacity
breaths should be carried out 39.
Rapid sequence intubation is indicated for all cases to minimise the
apnoea time during which significant aerosolisation can occur with
facemask ventilation. Therefore, facemask ventilation should only be
performed gently in the event of critical arterial oxygen desaturation 40.
In order to maximise first‐pass success and not compromise optimal
ventilation (if needed), cricoid force should not be performed, unless
there are other indications 41, 42. Apnoeic oxygenation is recommended to prevent desaturation 43, ideally with low‐flow nasal oxygenation during tracheal intubation attempts. Despite the benefits of high‐flow nasal oxygen 44,
it is an aerosol‐generating technique, particularly when the airway
operator is in close proximity to the patient, and should be avoided.
Cautious administration of general anaesthetic agents is
recommended to minimise haemodynamic instability, and rocuronium
1.2 mg.kg−1 or suxamethonium 1 mg.kg−1 should be given to ensure rapid onset of neuromuscular blockade, maximise first‐pass success 45
and prevent coughing and associated aerosolisation. Neuromuscular
monitoring is advisable. The most skilled and experienced airway
operator should perform airway instrumentation, and all conditions
should be optimised to ensure the highest chance of first‐pass tracheal
intubation success. We strongly recommend the use of a
videolaryngoscope, which would ideally be disposable but with a separate
screen to minimise patient contact. Pre‐loading an appropriately‐sized
tracheal tube on an introducer is also advised, as this may also improve
the first‐pass success rate 46.
In the event of a failed tracheal intubation, gentle
manual ventilation may be used, followed by a maximum of two attempts at
tracheal intubation (with consideration of change in position, device
and technique between attempts). After two failures, or any time if a
rescue airway is needed, a second generation supraglottic device is
strongly advised. Supraglottic airway devices that allow flexible
bronchoscopic intubation are preferable 47.
An early emergency front‐of‐neck airway (surgical or percutaneous
cricothyroidotomy) should be considered before a ‘cannot intubate,
cannot oxygenate’ scenario independently of critical arterial oxygen
desaturation 36.
If ATI is indicated, 37, 38, an experienced operator should perform it 48, 49 and administration of intravenous sedation may minimise coughing 50.
Aerosol or vaporised delivery of local anaesthesia should be minimised,
and consideration given to the use of mucosal atomisers, swabs and
tampons, and if clinical expertise permits, nerve blocks.
Ultrasound‐guided techniques could be adopted, though they might be
time‐consuming and carry challenges in terms of decontamination.
Single‐use flexible bronchoscopes should be used as they are associated
with a reduced risk of cross‐contamination 51,
and a separate screen is strongly advised. The diameter of the tracheal
tube should be the smallest appropriate to reduce the risk of tube
impingement on the arytenoids with consequent coughing. Awake tracheal
intubation with videolaryngoscopy is faster than with flexible
bronchoscopy and could be considered 52.
In the event of failed ATI, tracheostomy with local anaesthesia is a
viable alternative and must be considered, despite the potential for
aerosolisation 31.
Should a ‘cannot intubate, cannot oxygenate’ scenario occur, an
emergency front‐of‐neck airway should be performed with the
aforementioned principles.
Emergency tracheal intubation may be required for
COVID‐19 patients. This setting increases risks to patients and
healthcare workers and is often performed outside of the operating
theatre or intensive care environment. However, the acuity of airway
management should not compromise the safety of clinicians, and thus team
members must have PPE donned before commencing airway management. This
could require the delivery of gentle facemask ventilation in a hypoxic
patient to buy time for the patient and treating clinicians. Principles
of airway management in emergencies are like those in more controlled
settings.
After successful tracheal intubation, careful management
of the tracheal tube is crucial. Auscultation is not advisable due to
the challenges with PPE and the risk of cross‐contamination 23,
but confirmation of tracheal tube placement should ideally rely on
viewing the tracheal tube pass through the vocal cords, with an
appropriate and repeated capnographic trace and chest wall movement. All
of the aforementioned considerations need to be adopted for tracheal
tube exchange manoeuvres, and strategies for protected extubation should
be addressed, especially after prolonged tracheal intubation or
documented difficult airway management 53.
High‐efficiency particulate air filters should be placed between the
primary airway device and the breathing circuit, including the
expiratory limb of the circuit once the patient is connected to the
ventilator 54.
To prevent viral dispersion, unnecessary respiratory circuit
disconnections are discouraged. If disconnection is required, patient
sedation should be optimised to prevent coughing, the ventilator should
be turned to stand‐by mode and the tracheal tube clamped (Fig. 1).
Società Italiana di Anestesia Analgesia
Rianimazione e Terapia Intensiva guidance on airway management of the
patient with coronavirus disease 2019.
Non‐technical skills
The management of patients with COVID‐19 places
additional physical and psychological burdens on healthcare workers.
Physical burdens include repeated donning and doffing of PPE and
physical restrictions to routine practice due to PPE. Psychological
burdens include: management in unfamiliar environments; communication
challenges with PPE; and changes to standard practice. Identification of
suitable environments for airway management, team briefing and
co‐ordination, task assignment and briefings, team training and the use
of checklists and cognitive aids are all crucial to reduce physical and
cognitive work‐loads (Fig. 1).
To reduce physical risks, consideration of predefined
roles and ergonomics is imperative. There should be an independent
practitioner observing the donning and doffing of PPE 23, 55.
Only the most experienced healthcare workers with full PPE should be
present inside the isolation chamber. Suggested team assignments,
utilised in our clinical practice during this current crisis, include an
inner isolated chamber and an outer chamber (Fig. 2).
In the isolated chamber, all staff should have full PPE donned. Outside
of the chamber, additional PPE and other members of staff are
available.
Suggested team roles and ergonomics for elective tracheal intubation.
Personal protective equipment
Coronaviruses are typically found in the lower respiratory
tract linked with angiotensin converting enzyme receptors, with the
primary mechanism of transmission through contact and droplet spread of
respiratory secretions, which travel up to 2 m 10. The importance of PPE cannot be overstated, but clinicians must also be aware that effectiveness is rarely 100% 3.
Moreover, experiences in Italy have demonstrated that supplies of PPE
are unlikely to meet demand, thus the use of centralised storage and
distribution of PPE is recommended as well as considering the
preparation of dedicated PPE kits in keeping with WHO recommendations 17.
One of the key supply restrictions is that of appropriate
filtering face piece (FFP) masks. These are different to conventional
masks such as surgical masks as they create a facial seal, filtering the
air with different filter capacities (Table 3).
Although 2019‐nCoV has a size of 0.06–0.14 μm, the virus is carried
with droplets that are larger than 0.3 μm, and therefore facial
respirator masks with a filter against particles sized > 0.3 μm are
appropriate.
Table 3.
Filtering face piece (FFP) protection levels. FFP2, N95 and FFP3 masks are recommended for the management of COVID‐19 patients
Filter standard
Filter capacity (removal percentage of all particles ≥ 0.3 µm
FFP1
80%
FFP2
94%
N95
95%
FFP3
99%
N100
99.97%
COVID‐19, coronavirus disease 2019.
The levels of protection for airway management in COVID‐19
patients adopted in most of hospitals in Italy are either second‐ or
third‐level PPE, preferring the use of airborne‐level PPEs for critical
care aeorsol‐generating procedures, including tracheal intubation,
bronchoscopy and ATI. So far, the outbreak‐related global PPE shortage
has forced the use of lower‐protection PPEs for aeorsol‐generating
procedures. Airborne‐level protection should include: helmets, covers or
hoods; FFP3 or FFP2/N95 masks, goggles or face shields (if no helmets);
hazmat suits or long sleeved fluid‐resistant gowns; double gloves
(possibly different colours); and overshoes. Whenever possible, the
maximum available protection level should be used, especially for
aeorsol‐generating procedures.
Donning and doffing of PPE should be practiced and when
performed clinically, an external observer should supervise its
meticulous performance in accordance with checklists 23.
In our experience, PPE donning and doffing presents the greatest
challenge to daily working. In particular, doffing of PPE, especially
when clinicians are tired and cognitively overloaded, is associated with
the greatest risk of contamination. Team members should doff PPE
individually and one at a time. Cycles of thorough hand disinfection
must be undertaken and supervised, and meticulous waste disposal must be
completed.
Transport
Local protocols should be designed for post‐procedural
transport of patients with PPE and biocontainment procedures strictly
adhered to 55. This must factor staff and public safety during transport.
Briefing, debriefing and training
Pre‐procedural briefing and post‐procedural debriefing are
mandatory to review errors and determine improvements for future
practice. Team‐based simulation and training remains critical throughout
the evolution of this pandemic, involving any level of healthcare
professionals 56. The development of local protocols and checklists, development and adoption of dedicated early warning scores 57,
and accounting for regional variation in practice, is strongly
recommended given the number of clinicians involved, as well as the
risks to healthcare professionals.
Conclusion
We have faced many challenges with the onset of the COVID‐19
outbreak throughout Italy and it is likely that other countries will
face similar challenges in the coming weeks and months. We have shared
systemic and clinical knowledge and experiences gained during the course
of the Italian outbreak, with the aims of educating and supporting
clinicians elsewhere in the global healthcare community who may face
similar scenarios. Only with appropriate informed planning, training and
team working will healthcare systems be best placed to face this new
pandemic.
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