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The concept of neurocritical care has been developed to
coordinate the management of critically ill neurological patients
within a single specialist unit and to include clinical situations
such as swallowing disturbances, respiratory problems
management in neurocritical care, infection control in the unit,
pain relief and sedation in some patients, as well as diagnosing
brain death. Acute rehabilitation is important in securing
improved long-term neurological outcomes after many brain
insults, trauma, ischemia or hemorrhage. Intervention from
neurophysiotherapists, as part of the neurocritical care
multiprofessional team, must occur as early as possible.
Respiratory muscle impairment is the most common reason for
admission to the ICU in patients with neuromuscular disorders.
Objective measures of respiratory muscle function are necessary
because significant respiratory muscle impairment may exist
despite a paucity of symptoms.
Analgesia in the neurocritical care unit is indicated in many
situations such as postoperative pain, traumatic injury, and
subacute or chronic pains. Although it is mandatory and
beneficial in many situations, precautions must be taken before
coordinate the management of critically ill neurological patients
within a single specialist unit and to include clinical situations
such as swallowing disturbances, respiratory problems
management in neurocritical care, infection control in the unit,
pain relief and sedation in some patients, as well as diagnosing
brain death. Acute rehabilitation is important in securing
improved long-term neurological outcomes after many brain
insults, trauma, ischemia or hemorrhage. Intervention from
neurophysiotherapists, as part of the neurocritical care
multiprofessional team, must occur as early as possible.
Respiratory muscle impairment is the most common reason for
admission to the ICU in patients with neuromuscular disorders.
Objective measures of respiratory muscle function are necessary
because significant respiratory muscle impairment may exist
despite a paucity of symptoms.
Analgesia in the neurocritical care unit is indicated in many
situations such as postoperative pain, traumatic injury, and
subacute or chronic pains. Although it is mandatory and
beneficial in many situations, precautions must be taken before
applying many agents; e.g., equipment and personnel to intubate
and mechanically ventilate patients must be readily available
with use of narcotic agonists. Some agents may cause decreased
level of consciousness or obtundation leading to impairment of
neurological exam. This chapter will cover management of these
issues in the neurocritical care setting.
Swallowing Disturbances
Weakness, spasticity or both of the pharynx and tongue cause
dysphagia and tendency for aspiration. A feeding tube through a
percutaneous endoscopic gastrostomy (PEG), cervical
esophagostomy or jejunostomy is a reliable method of patient
feeding when prolonged deficit is expected. Nutrition support by
enteral feeding through either a nasogastric or an orogastric
tube should be maintained in all intubated patients whenever
possible. In patients with a normal baseline nutritional state,
support should be initiated within 7 days. In malnourished
patients, nutritional support should be initiated within 72 h.
Delayed gastric emptying is common in critically ill patients on
sedative medications but often responds to promotility agents
such as domperidone, and metoclopramide (Gomes 2010).
Parenteral nutrition is an alternative to enteral nutrition in
patients with severe gastrointestinal pathology. When patients
improve the gastrostomy is easy to close. It is better to try to
provide adequate and safe nutrition by mouth in an alert patient
before placing a feeding tube. Nasogastric tubes have been used
temporarily for feeding but they are uncomfortable, cause
pressure necrosis of the nares when used chronically, and allow
aspiration, so it should not be used for long. In ambulatory
patients with severe dysphagia, cervical esophagostomy may be
useful, as a patient can insert the tube during feedings and the
ostium can be covered with a dressing at other times. Patients
with severe weakness or ataxia of the upper extremities are
usually unable to feed themselves, so percutaneous endoscopic
gastrostomy is the method of choice (Wanklyn 1995). Tube
and mechanically ventilate patients must be readily available
with use of narcotic agonists. Some agents may cause decreased
level of consciousness or obtundation leading to impairment of
neurological exam. This chapter will cover management of these
issues in the neurocritical care setting.
Swallowing Disturbances
Weakness, spasticity or both of the pharynx and tongue cause
dysphagia and tendency for aspiration. A feeding tube through a
percutaneous endoscopic gastrostomy (PEG), cervical
esophagostomy or jejunostomy is a reliable method of patient
feeding when prolonged deficit is expected. Nutrition support by
enteral feeding through either a nasogastric or an orogastric
tube should be maintained in all intubated patients whenever
possible. In patients with a normal baseline nutritional state,
support should be initiated within 7 days. In malnourished
patients, nutritional support should be initiated within 72 h.
Delayed gastric emptying is common in critically ill patients on
sedative medications but often responds to promotility agents
such as domperidone, and metoclopramide (Gomes 2010).
Parenteral nutrition is an alternative to enteral nutrition in
patients with severe gastrointestinal pathology. When patients
improve the gastrostomy is easy to close. It is better to try to
provide adequate and safe nutrition by mouth in an alert patient
before placing a feeding tube. Nasogastric tubes have been used
temporarily for feeding but they are uncomfortable, cause
pressure necrosis of the nares when used chronically, and allow
aspiration, so it should not be used for long. In ambulatory
patients with severe dysphagia, cervical esophagostomy may be
useful, as a patient can insert the tube during feedings and the
ostium can be covered with a dressing at other times. Patients
with severe weakness or ataxia of the upper extremities are
usually unable to feed themselves, so percutaneous endoscopic
gastrostomy is the method of choice (Wanklyn 1995). Tube
feeding needs high caloric diet (1200 to 2400 Kcal/day) for active
patients, and liquid foods are usually concentrated to deliver
1 Kcal/ml. To avoid clogging of the tube, each feeding is followed
with water. Tube feeding is best started with about one half the
total desired calories diluted in water, with gradual increase in
concentration and calories, to avoid diarrhea and malabsorption,
reaching a maximum volume of about 200 ml (150 ml food and 50
ml of water). If aspiration of saliva and nasal secretions is a
problem, a cuffed endotracheal tube is necessary and the use of
tricyclic antidepressants or anticholinergic drugs (if there is no
absolute contraindication for its use) might reduce salivation
and prevent drooling (Fjærtoft 2011). Adequate nutritional
feeding, trace elements, minerals and vitamins constitute the
most important basic brain supplements.
Respiratory Management in Neurocritical Care
Most patients who are started on ventilatory support receive
synchronized intermittent mandatory ventilation (SIMV),
because this ensures user-specified backup minute ventilation in
the event that the patient fails to initiate respiratory efforts.
Once the intubated patient has been stabilized with respect to
oxygenation, definitive therapy for the underlying process
responsible for respiratory failure is formulated and initiated.
Subsequent modifications in ventilator therapy must be
provided in parallel with changes in the patient’s clinical status.
As improvement in respiratory function is noted, the first
priorities are to reduce PEEP and supplemental O2 and once a
patient can achieve adequate arterial saturation with an FIO2
≤0.5 and 5 cm H2O PEEP, attempts should be made to reduce the
level of mechanical ventilatory support and weaning should be
planned and started. Patients previously on full ventilator
support should be switched to a ventilator mode that allows for
weaning, such as SIMV, PSV (pressure support ventilation), or
SIMV combined with PSV. Ventilator therapy can then be
gradually removed while patients whose condition continues to
patients, and liquid foods are usually concentrated to deliver
1 Kcal/ml. To avoid clogging of the tube, each feeding is followed
with water. Tube feeding is best started with about one half the
total desired calories diluted in water, with gradual increase in
concentration and calories, to avoid diarrhea and malabsorption,
reaching a maximum volume of about 200 ml (150 ml food and 50
ml of water). If aspiration of saliva and nasal secretions is a
problem, a cuffed endotracheal tube is necessary and the use of
tricyclic antidepressants or anticholinergic drugs (if there is no
absolute contraindication for its use) might reduce salivation
and prevent drooling (Fjærtoft 2011). Adequate nutritional
feeding, trace elements, minerals and vitamins constitute the
most important basic brain supplements.
Respiratory Management in Neurocritical Care
Most patients who are started on ventilatory support receive
synchronized intermittent mandatory ventilation (SIMV),
because this ensures user-specified backup minute ventilation in
the event that the patient fails to initiate respiratory efforts.
Once the intubated patient has been stabilized with respect to
oxygenation, definitive therapy for the underlying process
responsible for respiratory failure is formulated and initiated.
Subsequent modifications in ventilator therapy must be
provided in parallel with changes in the patient’s clinical status.
As improvement in respiratory function is noted, the first
priorities are to reduce PEEP and supplemental O2 and once a
patient can achieve adequate arterial saturation with an FIO2
≤0.5 and 5 cm H2O PEEP, attempts should be made to reduce the
level of mechanical ventilatory support and weaning should be
planned and started. Patients previously on full ventilator
support should be switched to a ventilator mode that allows for
weaning, such as SIMV, PSV (pressure support ventilation), or
SIMV combined with PSV. Ventilator therapy can then be
gradually removed while patients whose condition continues to
deteriorate after ventilator support is initiated may require
increased O2, PEEP, and alternative modes of ventilation such as
IRV or OLV (Borel 2000). Patients who are started on mechanical
ventilation usually require some form of sedation and analgesia
to maintain an acceptable level of comfort. Often, this regimen
consists of a combination of a benzodiazepine and opiate
administered intravenously. Medications commonly used for this
purpose include lorazepam, midazolam, diazepam, morphine,
and fentanyl. Immobilized patients in the intensive care unit on
mechanical ventilatory support are at increased risk for deep
venous thrombosis; accepted practice consists of administering
prophylaxis in the form of subcutaneous heparin and/or
pneumatic compression boots. Fractionated low-molecularweight
heparin has also been used for this purpose; it appears to
be equally effective and is associated with a decreased incidence
of heparin-associated thrombocytopenia (Pelosi 2011).
Prophylaxis against diffuse gastrointestinal mucosal injury is
indicated for patients who have suffered a neurologic insult, so
histamine receptor antagonists (H2 receptor antagonists), proton
pump inhibitors, and cytoprotective agents such as Carafate
have all been used for this purpose and appear to be effective.
Recent data suggest that Carafate use is associated with a
reduction in the incidence of nosocomial pneumonias, since it
does not cause changes in stomach PH and is less likely to permit
colonization of the gastrointestinal tract by nosocomial
organisms at neutral PH.
Endotracheal intubation and positive-pressure mechanical
ventilation have direct and indirect effects on several organ
systems, including the lung and upper airways, the
cardiovascular system, and the gastrointestinal system.
Pulmonary complications include barotraumas, nosocomial
pneumonia, oxygen toxicity, tracheal stenosis, and
deconditioning of respiratory muscles (Hurford 2002).
Upper airway function must be intact for a patient to remain
extubated but is difficult to assess in the intubated patient.
Therefore, if a patient can breathe on his own, through an
increased O2, PEEP, and alternative modes of ventilation such as
IRV or OLV (Borel 2000). Patients who are started on mechanical
ventilation usually require some form of sedation and analgesia
to maintain an acceptable level of comfort. Often, this regimen
consists of a combination of a benzodiazepine and opiate
administered intravenously. Medications commonly used for this
purpose include lorazepam, midazolam, diazepam, morphine,
and fentanyl. Immobilized patients in the intensive care unit on
mechanical ventilatory support are at increased risk for deep
venous thrombosis; accepted practice consists of administering
prophylaxis in the form of subcutaneous heparin and/or
pneumatic compression boots. Fractionated low-molecularweight
heparin has also been used for this purpose; it appears to
be equally effective and is associated with a decreased incidence
of heparin-associated thrombocytopenia (Pelosi 2011).
Prophylaxis against diffuse gastrointestinal mucosal injury is
indicated for patients who have suffered a neurologic insult, so
histamine receptor antagonists (H2 receptor antagonists), proton
pump inhibitors, and cytoprotective agents such as Carafate
have all been used for this purpose and appear to be effective.
Recent data suggest that Carafate use is associated with a
reduction in the incidence of nosocomial pneumonias, since it
does not cause changes in stomach PH and is less likely to permit
colonization of the gastrointestinal tract by nosocomial
organisms at neutral PH.
Endotracheal intubation and positive-pressure mechanical
ventilation have direct and indirect effects on several organ
systems, including the lung and upper airways, the
cardiovascular system, and the gastrointestinal system.
Pulmonary complications include barotraumas, nosocomial
pneumonia, oxygen toxicity, tracheal stenosis, and
deconditioning of respiratory muscles (Hurford 2002).
Upper airway function must be intact for a patient to remain
extubated but is difficult to assess in the intubated patient.
Therefore, if a patient can breathe on his own, through an
endotracheal tube, but develops stridor or recurrent aspiration
once the tube is removed, upper airway dysfunction or an
abnormal swallowing mechanism should be suspected, and plans
for achieving a stable airway be developed. An intact cough
reflex during suctioning is a good indicator of a patient’s ability
to mobilize secretions. Respiratory drive and chest wall
functions are assessed by observation of respiratory rate, tidal
volume, inspiratory pressure, and vital capacity (Hardin 2006).
The weaning index, defined as the ratio of breathing frequency
to tidal volume (breaths per minute per liter), is both sensitive
and specific for predicting the likelihood of successful
extubation. When this ratio is less than 105, and the patient can
breathe without mechanical assistance through an endotracheal
tube, successful extubation is likely. An inspiratory pressure of
more than −30 cm H2O and a vital capacity of greater than 10
ml/kg are considered indicators of acceptable chest wall and
diaphragm functions. Alveolar ventilation is generally adequate
when elimination of CO2 is sufficient to maintain arterial pH in
the range of 7.35 to 7.40, and SaO2 >90% can be achieved with an
FIO2 <0.5 and a PEEP ≤5 cm H2O. Although many patients may not
meet all criteria for weaning, the likelihood that a patient will
tolerate extubation without difficulty increases as more criteria
are met (Hurford 2002).
Many approaches to wean patients from ventilator support
have been advocated. T-piece and CPAP weaning are best
tolerated by patients who have undergone mechanical
ventilation for brief periods and require little respiratory muscle
reconditioning, whereas SIMV and PSV are best for patients who
have been intubated for extended periods and require gradual
respiratory muscle reconditioning. Weaning by means of SIMV
involves gradual tapering of the mandatory backup rate, in
increments of 2 to 4 breaths per minute, while monitoring blood
gas parameters and respiratory rates (Webb 1999). Rates of
greater than 25 breaths per minute, on withdrawal of mandatory
ventilator breaths, generally indicate respiratory muscle fatigue
and the need to combine periods of exercise with periods of rest.
once the tube is removed, upper airway dysfunction or an
abnormal swallowing mechanism should be suspected, and plans
for achieving a stable airway be developed. An intact cough
reflex during suctioning is a good indicator of a patient’s ability
to mobilize secretions. Respiratory drive and chest wall
functions are assessed by observation of respiratory rate, tidal
volume, inspiratory pressure, and vital capacity (Hardin 2006).
The weaning index, defined as the ratio of breathing frequency
to tidal volume (breaths per minute per liter), is both sensitive
and specific for predicting the likelihood of successful
extubation. When this ratio is less than 105, and the patient can
breathe without mechanical assistance through an endotracheal
tube, successful extubation is likely. An inspiratory pressure of
more than −30 cm H2O and a vital capacity of greater than 10
ml/kg are considered indicators of acceptable chest wall and
diaphragm functions. Alveolar ventilation is generally adequate
when elimination of CO2 is sufficient to maintain arterial pH in
the range of 7.35 to 7.40, and SaO2 >90% can be achieved with an
FIO2 <0.5 and a PEEP ≤5 cm H2O. Although many patients may not
meet all criteria for weaning, the likelihood that a patient will
tolerate extubation without difficulty increases as more criteria
are met (Hurford 2002).
Many approaches to wean patients from ventilator support
have been advocated. T-piece and CPAP weaning are best
tolerated by patients who have undergone mechanical
ventilation for brief periods and require little respiratory muscle
reconditioning, whereas SIMV and PSV are best for patients who
have been intubated for extended periods and require gradual
respiratory muscle reconditioning. Weaning by means of SIMV
involves gradual tapering of the mandatory backup rate, in
increments of 2 to 4 breaths per minute, while monitoring blood
gas parameters and respiratory rates (Webb 1999). Rates of
greater than 25 breaths per minute, on withdrawal of mandatory
ventilator breaths, generally indicate respiratory muscle fatigue
and the need to combine periods of exercise with periods of rest.
Exercise periods are gradually increased until a patient remains
stable on SIMV at 4 breaths per minute or less without needing
rest at higher SIMV rates. A CPAP or T-piece trial can then be
attempted before planned extubation (Bernard 1994).
Infection Control in Neurocritical Care
Sepsis (and the systemic inflammatory response to sepsis)
remains the major cause of organ failure and death in the
intensive care unit, being either directly or indirectly
responsible for 75% of all deaths (Valles 1997). Common sites of
infection include the urinary tract, respiratory tract (especially
ventilator associated pneumonia), vascular cannulae (catheter
related sepsis) and long-term use of nasogastric feeding tubes.
Vascular cannulae sepsis, particularly those associated with
internal jugular and subclavian catheters, constitute the
majority, but peripheral catheters also carry a considerable risk
of infections. Thus, placement of intravenous lines requires
careful aseptic technique and regular changing of lines. It is
important to culture specimens from the tips of catheters that
have been removed. Catheter related infections are usually
caused by Staphylococcus epidermidis or Staphylococcus aureus, and
its treatment is empiric depending on use of vancomycin and
cephalosporins.
Most nosocomial infections seen in the NICU are endogenous,
caused by colonization of the patient’s GI tract by pathogenic
bacteria which then translocate through the intestinal mucosa to
reach distant sites by hematogenous spread. With vascular
cannulation, Gram-negative organisms such as Escherichia coli,
Klebsiella, and Pseudomonas species stated to be traditionally
responsible, but Gram-positive organisms (Streptococcus and
Staphylococcus species) are increasingly suspected. Fungi may
also be implicated and considered the most serious infection
(Vincent 1995).
Patients intubated for longer than 72 hours are at high risk for
ventilator-associated pneumonia as a result of aspiration from
stable on SIMV at 4 breaths per minute or less without needing
rest at higher SIMV rates. A CPAP or T-piece trial can then be
attempted before planned extubation (Bernard 1994).
Infection Control in Neurocritical Care
Sepsis (and the systemic inflammatory response to sepsis)
remains the major cause of organ failure and death in the
intensive care unit, being either directly or indirectly
responsible for 75% of all deaths (Valles 1997). Common sites of
infection include the urinary tract, respiratory tract (especially
ventilator associated pneumonia), vascular cannulae (catheter
related sepsis) and long-term use of nasogastric feeding tubes.
Vascular cannulae sepsis, particularly those associated with
internal jugular and subclavian catheters, constitute the
majority, but peripheral catheters also carry a considerable risk
of infections. Thus, placement of intravenous lines requires
careful aseptic technique and regular changing of lines. It is
important to culture specimens from the tips of catheters that
have been removed. Catheter related infections are usually
caused by Staphylococcus epidermidis or Staphylococcus aureus, and
its treatment is empiric depending on use of vancomycin and
cephalosporins.
Most nosocomial infections seen in the NICU are endogenous,
caused by colonization of the patient’s GI tract by pathogenic
bacteria which then translocate through the intestinal mucosa to
reach distant sites by hematogenous spread. With vascular
cannulation, Gram-negative organisms such as Escherichia coli,
Klebsiella, and Pseudomonas species stated to be traditionally
responsible, but Gram-positive organisms (Streptococcus and
Staphylococcus species) are increasingly suspected. Fungi may
also be implicated and considered the most serious infection
(Vincent 1995).
Patients intubated for longer than 72 hours are at high risk for
ventilator-associated pneumonia as a result of aspiration from
the upper airways through small leaks around the endotracheal
tube cuff; the most common organisms responsible for these
conditions are enteric gram-negative rods, Staphylococcus aureus,
and anaerobic bacteria. Because the endotracheal tube and
upper airways of patients on mechanical ventilation are
commonly colonized with bacteria, the diagnosis of nosocomial
pneumonia requires “protected brush” bronchoscopic sampling
of airway secretions coupled with quantitative microbiologic
techniques to differentiate colonization from infection.
Precautions and ways to combat nosocomial infections involve
the isolation of the infected patient whenever possible,
meticulous staff hygiene (hand washing before and after each
patient contact, aseptic techniques for invasive procedures, etc),
early identification and treatment of infection by the routine
sending of blood, urine, sputum, etc, for culture, use of
disposable equipments and, most importantly, joint daily ward
rounds between microbiologists and the ICU team (Fagon 1993).
Treatment of nosocomial infection, with or without septicemia,
requires the administration of appropriate antibacterial drugs in
adequate doses for an appropriate period.
Pain Relief and Sedation
In neurocritical care units different scores are used to evaluate
patient anxiety, agitation and response to surroundings.
Different scores for pain, anxiety and agitation are used as
guidelines for medication when pain is common, with a variety
of causes such as anxiety, confusion, sleep deprivation, sepsis,
drug withdrawal – especially sedatives, metabolic (hypo- or
hyperglycemia, hypernatremia, uremia, hepatic precoma or
coma), respiratory (infection, hypoxemia, hypercapnia) and
cardiac (low output state, hypotension). It may manifest as
discomfort, pulling at intravenous and bladder catheters,
tracheal and nasogastric tubes, shouting, aggressive behavior,
extreme restlessness, and confusion (Schnakers 2007). Pain is
particularly common and often unrecognized because of
tube cuff; the most common organisms responsible for these
conditions are enteric gram-negative rods, Staphylococcus aureus,
and anaerobic bacteria. Because the endotracheal tube and
upper airways of patients on mechanical ventilation are
commonly colonized with bacteria, the diagnosis of nosocomial
pneumonia requires “protected brush” bronchoscopic sampling
of airway secretions coupled with quantitative microbiologic
techniques to differentiate colonization from infection.
Precautions and ways to combat nosocomial infections involve
the isolation of the infected patient whenever possible,
meticulous staff hygiene (hand washing before and after each
patient contact, aseptic techniques for invasive procedures, etc),
early identification and treatment of infection by the routine
sending of blood, urine, sputum, etc, for culture, use of
disposable equipments and, most importantly, joint daily ward
rounds between microbiologists and the ICU team (Fagon 1993).
Treatment of nosocomial infection, with or without septicemia,
requires the administration of appropriate antibacterial drugs in
adequate doses for an appropriate period.
Pain Relief and Sedation
In neurocritical care units different scores are used to evaluate
patient anxiety, agitation and response to surroundings.
Different scores for pain, anxiety and agitation are used as
guidelines for medication when pain is common, with a variety
of causes such as anxiety, confusion, sleep deprivation, sepsis,
drug withdrawal – especially sedatives, metabolic (hypo- or
hyperglycemia, hypernatremia, uremia, hepatic precoma or
coma), respiratory (infection, hypoxemia, hypercapnia) and
cardiac (low output state, hypotension). It may manifest as
discomfort, pulling at intravenous and bladder catheters,
tracheal and nasogastric tubes, shouting, aggressive behavior,
extreme restlessness, and confusion (Schnakers 2007). Pain is
particularly common and often unrecognized because of
confusion and the difficulties with communication in the
aphonic, aphasic or paralyzed patient. Clinical assessment may
direct attention through finding of profuse sweating, sustained
tachycardia and blood pressure fluctuations, and dilated pupils.
Most patients will require sedation but there is a natural
reluctance to sedate patients with an evolving CNS disorder
(McMillian 2011).
The first line of management is to reassure and calm the
patient, ensuring a quiet environment and normal diurnal cycle.
Next, there should be careful nursing and treatment of the
underlying causes, including positioning, splinting, bed cages,
catheterization, and physical treatments. In spite of reluctance
to sedate patients with an evolving CNS disorder, sedative
medications are mandatory and must be used, when indicated, to
reduce pain, distress, and anxiety. Also they may be used to help
patient toleration of tracheal tubes, IPPV, tracheal suction, and
physiotherapy. Patients with neurologically-induced respiratory
failure often require prolonged periods of mechanical
ventilation in the NICU, and it is not desirable to keep such
patients continuously sedated throughout their stay (Jacobi
2002). Furthermore, assessment of their condition and
subsequent weaning is impossible when sedated. However,
during periods of cardiorespiratory instability, raised ICP, and in
cases of intubation, sedation may be essential. In the ICU
environment, however, medications are often needed to calm
patients. As many as 30 different medications are used, and the
agents most frequently used are midazolam, olanzapine,
propofol, lorazepam and opioid analgesics (Jacobi 2002).
Bedside approach to the agitated patient
Assess and manage immediate threat to life (airway, breathing,
circulation and temperature).
Assess pain by querying the patient about pain, and assess for
noxious stimuli after measurement of pain score. Correct any
identified causes, and if the patient is hemodynamically
unstable, give fentanyl 25-100 μgm IV q5-15 minutes until
aphonic, aphasic or paralyzed patient. Clinical assessment may
direct attention through finding of profuse sweating, sustained
tachycardia and blood pressure fluctuations, and dilated pupils.
Most patients will require sedation but there is a natural
reluctance to sedate patients with an evolving CNS disorder
(McMillian 2011).
The first line of management is to reassure and calm the
patient, ensuring a quiet environment and normal diurnal cycle.
Next, there should be careful nursing and treatment of the
underlying causes, including positioning, splinting, bed cages,
catheterization, and physical treatments. In spite of reluctance
to sedate patients with an evolving CNS disorder, sedative
medications are mandatory and must be used, when indicated, to
reduce pain, distress, and anxiety. Also they may be used to help
patient toleration of tracheal tubes, IPPV, tracheal suction, and
physiotherapy. Patients with neurologically-induced respiratory
failure often require prolonged periods of mechanical
ventilation in the NICU, and it is not desirable to keep such
patients continuously sedated throughout their stay (Jacobi
2002). Furthermore, assessment of their condition and
subsequent weaning is impossible when sedated. However,
during periods of cardiorespiratory instability, raised ICP, and in
cases of intubation, sedation may be essential. In the ICU
environment, however, medications are often needed to calm
patients. As many as 30 different medications are used, and the
agents most frequently used are midazolam, olanzapine,
propofol, lorazepam and opioid analgesics (Jacobi 2002).
Bedside approach to the agitated patient
Assess and manage immediate threat to life (airway, breathing,
circulation and temperature).
Assess pain by querying the patient about pain, and assess for
noxious stimuli after measurement of pain score. Correct any
identified causes, and if the patient is hemodynamically
unstable, give fentanyl 25-100 μgm IV q5-15 minutes until
desired effect is achieved, or hydromorphone 0.25-0.75 mg IV
q 5-15 minutes; if patient is hemodynamically stable, give
morphine 2-5 mg IV every 5-15 minutes.
Assess anxiety. When patients have been on sedative and
analgesic drug infusions for longer than 24 hours and begin to
recover, daily interruptions of drug infusions for a time period
sufficient to allow awakening is recommended (Blanchard 2002).
Role of Rehabilitation
Rehabilitation is a reiterative active, educational, problemsolving
process, focused on the patient disability. The
operational characteristics of rehabilitation services comprise a
multidisciplinary group of people who work together towards
common goals for each patient, involve and educate the patient
and family in the process, have relevant expertise and
experience (knowledge and skills) and can, between them,
resolve most of the common problems faced by patients (Arnow
1993). The stages of rehabilitation involve general assessment to
identify the nature and extent of the patient problems and the
factors relevant to their solution, goal setting, then intervention,
which may include treatments that affect the process of change
and support (care), which maintain life and safety, and finally
evaluation to check on the effects of the intervention.
The aims of rehabilitation are to maximize the participation of
the patient in his/her social setting, minimize the pain and
distress experienced by the patient and family and/or carers
(Collen 1990). The development of models for disability has
fostered and clarified discussion about the nature of
rehabilitation. Definition of rehabilitation refers to the
operational characteristics of a rehabilitation service (structure),
how rehabilitation service works (process) and the aims of
rehabilitation services (outcome).
Three specific core skills are particularly associated with
q 5-15 minutes; if patient is hemodynamically stable, give
morphine 2-5 mg IV every 5-15 minutes.
Assess anxiety. When patients have been on sedative and
analgesic drug infusions for longer than 24 hours and begin to
recover, daily interruptions of drug infusions for a time period
sufficient to allow awakening is recommended (Blanchard 2002).
Role of Rehabilitation
Rehabilitation is a reiterative active, educational, problemsolving
process, focused on the patient disability. The
operational characteristics of rehabilitation services comprise a
multidisciplinary group of people who work together towards
common goals for each patient, involve and educate the patient
and family in the process, have relevant expertise and
experience (knowledge and skills) and can, between them,
resolve most of the common problems faced by patients (Arnow
1993). The stages of rehabilitation involve general assessment to
identify the nature and extent of the patient problems and the
factors relevant to their solution, goal setting, then intervention,
which may include treatments that affect the process of change
and support (care), which maintain life and safety, and finally
evaluation to check on the effects of the intervention.
The aims of rehabilitation are to maximize the participation of
the patient in his/her social setting, minimize the pain and
distress experienced by the patient and family and/or carers
(Collen 1990). The development of models for disability has
fostered and clarified discussion about the nature of
rehabilitation. Definition of rehabilitation refers to the
operational characteristics of a rehabilitation service (structure),
how rehabilitation service works (process) and the aims of
rehabilitation services (outcome).
Three specific core skills are particularly associated with
rehabilitation:
1. An ability to assess all relevant aspects of patients’ situation
not simply their disease and its symptoms and signs, formulating
the important interactions.
2. An ability to set realistic but challenging goals in both the
short and long term, a skill that depends upon an accurate
evaluation of the likely prognosis and scope for effective
intervention.
3. An ability to participate in teamwork, working co-operatively
with a group of other experts towards agreed common goals
(Cunningham 2000).
However, recent research, mostly related to stroke, does
support various hypotheses. First, there is now evidence that
even quite small levels of intervention can have powerful and
specific effects. There is also some evidence of a dose response
relationship between therapeutic input and outcome. Second,
there is some evidence that even the simple provision of
information may be effective and acting on the patient’s
personal context is an important component of rehabilitation
(Badley 1993). Third, patients should be encouraged to seek
review of medication at regular intervals, perhaps every 6
months, especially for drugs that have cognitive side effects and
either slow or hinder the process of recovery. Use drugs to treat
specific impairments like gabapentin to improve visual acuity
when nystagmus is present, and a dopamine agonist (such as
bromocriptine) to ameliorate the reduced initiation after frontal
lobe damage. Acute-onset disability is often considered the
easiest to manage, because recovery occurs and may be complete
(Wade 2000).
Diagnostic Findings in Cerebral Death
Brain death is the irreversible cessation of cerebral functions.
Cerebral death, which is of medico-legal importance, cannot be
accurately assessed on the basis of a criterion related to a single
functional system. It is basically characterized by the absence of
three main brain functions:
not simply their disease and its symptoms and signs, formulating
the important interactions.
2. An ability to set realistic but challenging goals in both the
short and long term, a skill that depends upon an accurate
evaluation of the likely prognosis and scope for effective
intervention.
3. An ability to participate in teamwork, working co-operatively
with a group of other experts towards agreed common goals
(Cunningham 2000).
However, recent research, mostly related to stroke, does
support various hypotheses. First, there is now evidence that
even quite small levels of intervention can have powerful and
specific effects. There is also some evidence of a dose response
relationship between therapeutic input and outcome. Second,
there is some evidence that even the simple provision of
information may be effective and acting on the patient’s
personal context is an important component of rehabilitation
(Badley 1993). Third, patients should be encouraged to seek
review of medication at regular intervals, perhaps every 6
months, especially for drugs that have cognitive side effects and
either slow or hinder the process of recovery. Use drugs to treat
specific impairments like gabapentin to improve visual acuity
when nystagmus is present, and a dopamine agonist (such as
bromocriptine) to ameliorate the reduced initiation after frontal
lobe damage. Acute-onset disability is often considered the
easiest to manage, because recovery occurs and may be complete
(Wade 2000).
Diagnostic Findings in Cerebral Death
Brain death is the irreversible cessation of cerebral functions.
Cerebral death, which is of medico-legal importance, cannot be
accurately assessed on the basis of a criterion related to a single
functional system. It is basically characterized by the absence of
three main brain functions:
(1) Cerebral activity known as “cerebral responsivity”
(2) Vital functions
(3) Cephalic reflexes
Cephalic reflexes are mediated by the cranial nerves, and are
considered as important indicators of the integrity of the
brainstem, as absence of the cephalic reflexes are essential for
considering the diagnosis of brain death, yet they differ in
importance as a criterion of death. Some cephalic reflexes are
considered to be the most sensitive and discriminative of
brainstem functions, and accepted as criteria of cerebral brain
death, e.g., pupillary reflex was absent in 98.4% of cases, corneal
reflex was absent in practically all cases, and returns early if the
patient shows any signs of survival (unless the cornea has
become insensitive due to edema or dehydration), the
oculocephalic reflex (Doll’s eyes response) is quite
discriminative, and it returns early, with evidence of recovery.
The vestibular reflex is also quite discriminative for cerebral
death, but upon recovery, it is slightly slower to return than the
pupillary and corneal reflexes. The audio-ocular reflex, which is
a blink of the eyelids in response to a sudden clap, is not as
discriminative as the other cephalic reflexes, and is somewhat
slower to recover. Snout reflex, pharyngeal (gag) reflex,
swallowing reflex and cough reflex are not particularly
discriminative.
In the collaborative study of cerebral death, absence of all
cephalic reflexes was noted in more than half of the cases,
whereas audio-ocular reflex was absent in 99% of cases, the
pupillary reflex was absent in only 76.6%, and the audio-ocular
reflex was extremely sensitive to brain injury.
Certain combinations of cranial nerve reflexes have been
specified as essential for the diagnosis of brain death. The
absence of pupillary, corneal, vestibular, audio-ocular and
oculocephalic reflexes showed significant correlation with
cerebral death (Smith 1973), so all clinical tests are needed to
declare brain death and are likely essential.
(2) Vital functions
(3) Cephalic reflexes
Cephalic reflexes are mediated by the cranial nerves, and are
considered as important indicators of the integrity of the
brainstem, as absence of the cephalic reflexes are essential for
considering the diagnosis of brain death, yet they differ in
importance as a criterion of death. Some cephalic reflexes are
considered to be the most sensitive and discriminative of
brainstem functions, and accepted as criteria of cerebral brain
death, e.g., pupillary reflex was absent in 98.4% of cases, corneal
reflex was absent in practically all cases, and returns early if the
patient shows any signs of survival (unless the cornea has
become insensitive due to edema or dehydration), the
oculocephalic reflex (Doll’s eyes response) is quite
discriminative, and it returns early, with evidence of recovery.
The vestibular reflex is also quite discriminative for cerebral
death, but upon recovery, it is slightly slower to return than the
pupillary and corneal reflexes. The audio-ocular reflex, which is
a blink of the eyelids in response to a sudden clap, is not as
discriminative as the other cephalic reflexes, and is somewhat
slower to recover. Snout reflex, pharyngeal (gag) reflex,
swallowing reflex and cough reflex are not particularly
discriminative.
In the collaborative study of cerebral death, absence of all
cephalic reflexes was noted in more than half of the cases,
whereas audio-ocular reflex was absent in 99% of cases, the
pupillary reflex was absent in only 76.6%, and the audio-ocular
reflex was extremely sensitive to brain injury.
Certain combinations of cranial nerve reflexes have been
specified as essential for the diagnosis of brain death. The
absence of pupillary, corneal, vestibular, audio-ocular and
oculocephalic reflexes showed significant correlation with
cerebral death (Smith 1973), so all clinical tests are needed to
declare brain death and are likely essential.
Spinal reflexes may sometimes be present but they are not
relevant in establishing brain death. Isolated clinical studies,
electroencephalographic (EEG) examination and even blood flow
determination, fall short of an absolute diagnosis of cerebral
death.
Repetitive studies of a single functional system provide greater
confidence but the time period is long and many patients die of
cardiac arrest before they meet the criteria for cerebral death
(George 1991). Within limits, the shorter the period of
observation the more individuals may be diagnosed as cerebrally
dead (Smith 1973), so after the first rapid evaluation, the clinical
data should be confirmed by the following tests:
– conventional or CT angiography which shows no
intracerebral filling at the level of the carotid bifurcation or
Circle of Willis, patency of the external carotid circulation,
and a delay in the filling of the superior longitudinal sinus
(Brodac 1974; Frampas 2009),
– electroencephalography which shows no electrical activity
for at least 30 minutes of recording in suspected brain death,
as adopted by the American Electroencephalographic
Society (Benett 1978), including 16 channel
electroencephalographic instruments,
– transcranial Doppler ultrasonography; ten per cent of
patients may not have temporal insonation windows,
therefore the initial absence of Doppler signals cannot be
interpreted as consistent with brain death; small systolic
peaks in early systole without diastolic flow or reverberating
flow, indicating very high vascular resistance associated
with greatly increased intracranial pressure (Ropper 1987),
– technetium 99m hexamethyl propylene amineoxime brain
scan: no uptake of isotope in brain (Hollow skull
phenomenon),
– somatosensory evoked potentials which showed bilateral
absence of N20-P23 response with median nerve stimulation,
and its recordings should adhere to the minimal technical
relevant in establishing brain death. Isolated clinical studies,
electroencephalographic (EEG) examination and even blood flow
determination, fall short of an absolute diagnosis of cerebral
death.
Repetitive studies of a single functional system provide greater
confidence but the time period is long and many patients die of
cardiac arrest before they meet the criteria for cerebral death
(George 1991). Within limits, the shorter the period of
observation the more individuals may be diagnosed as cerebrally
dead (Smith 1973), so after the first rapid evaluation, the clinical
data should be confirmed by the following tests:
– conventional or CT angiography which shows no
intracerebral filling at the level of the carotid bifurcation or
Circle of Willis, patency of the external carotid circulation,
and a delay in the filling of the superior longitudinal sinus
(Brodac 1974; Frampas 2009),
– electroencephalography which shows no electrical activity
for at least 30 minutes of recording in suspected brain death,
as adopted by the American Electroencephalographic
Society (Benett 1978), including 16 channel
electroencephalographic instruments,
– transcranial Doppler ultrasonography; ten per cent of
patients may not have temporal insonation windows,
therefore the initial absence of Doppler signals cannot be
interpreted as consistent with brain death; small systolic
peaks in early systole without diastolic flow or reverberating
flow, indicating very high vascular resistance associated
with greatly increased intracranial pressure (Ropper 1987),
– technetium 99m hexamethyl propylene amineoxime brain
scan: no uptake of isotope in brain (Hollow skull
phenomenon),
– somatosensory evoked potentials which showed bilateral
absence of N20-P23 response with median nerve stimulation,
and its recordings should adhere to the minimal technical
criteria for somatosensory evoked potentials recording in
suspected brain death as adopted by the American
electrophysiological society (Benett 1978).
Conclusion
A neurological intensive care unit requires a multidisciplinary
approach to the management of critically ill patients. The
intensivists’ and neurologists’ attention to communication, daily
nursing care, physical therapy, and infection control will ensure
the best outcome (Rivers 2001).
suspected brain death as adopted by the American
electrophysiological society (Benett 1978).
Conclusion
A neurological intensive care unit requires a multidisciplinary
approach to the management of critically ill patients. The
intensivists’ and neurologists’ attention to communication, daily
nursing care, physical therapy, and infection control will ensure
the best outcome (Rivers 2001).
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