PeriOp stroke Flashcards
Key points
Key points
- The incidence of perioperative stroke after non-cardiac surgery is 0.1–1.9%.
- Patients should be screened for risk factors for perioperative stroke.
- Elective surgery should preferably be delayed for 9 months after a previous stroke;
emergency surgery should not be delayed. - Perioperative strokes are under-recognised and are associated with a high morbidity and mortality.
- Covert stroke occurs in 7% of patients undergoing non-cardiac surgeries and is associated with postoperative cognitive decline.
Summary pf recommended management
Defn
overt
covert
Definition and aetiology of perioperative stroke
The SNACC Consensus Statement defines ‘perioperative stroke’ as a brain infarction of ischaemic or haemorrhagic aetiology that occurs during surgery or within 30 days after surgery.
‘overt stroke’ is an acute brain infarct with clinical manifestation lasting longer than 24 h, and
‘covert stroke’ represents a brain infarct that is not recognised at the time of onset because of unappreciated subtle or misclassified clinical manifestations but is detected on brain imaging done at the time or subsequently
cause
incidence
Perioperative strokes can result from multiple aetiologies. The majority of perioperative strokes are reported to be cardioembolic in origin.3 Many anaesthetists believe intraoperative hypotension is a common cause.5 However, perioperative strokes resulting solely from hypoperfusion are relatively uncommon.
overall incidence for perioperative stroke of 0.1%, increasing to 1.9% in a subset of high-risk patients.
Risk factors
Patient
advancing age
TIA / CVA
AF
Vavlular diz
CV dis
Renal disease
DM
Smoker / COPD
PFO
Surgical
Vascular surgery
Thoracic surgery
Tplx surgery
Endocrine surgery
ENT surgery
Hemicolectomy
Prevention of Perio Stroke
- Carotid stenosis
Present surgery - evaluated gen stroke RF
incl stenosis
Further intervent - established guideline
Propylactic sx not recommended
Recommended for symptomatic high grade stenosis
50-99%
Stenting considered high risk candidate
- Anticoagulation
BRIDGE) trial
i. not bridging was non-inferior to bridging for the prevention of arterial thromboembolism
ii. Bridging with LMWH resulted in a nearly three-fold greater incidence of major bleeding
more cautious approach in those at higher risk of periprocedural stroke
(e.g. CHADS2 score >3, recent transient ischaemic attack or stroke, rheumatic heart disease or mechanical heart valve)
DOACs) for atrial fibrillation (i.e. apixaban, dabigatran or rivaroxaban), a temporary interruption of 1–2 days before and resumption 1–3 days after surgery resulted in a low rate of arterial thromboembolism or ischaemic stroke
Anti platelets
(POISE-2) trial
eceive either aspirin or placebo
No difference in the primary outcome (death or non-fatal myocardial infarction) was found, and aspirin did not result in a significant reduction in stroke
imilar to the bridging of anticoagulation trial discussed above, perioperative aspirin treatment resulted in an increased risk of major bleeding in this study. Therefore, the continuation or initiation of aspirin does not appear to confer protection against perioperative stroke in non-cardiac surgery, non-neurological surgery.
Prevention of Perio Stroke
- Carotid stenosis
Present surgery - evaluated gen stroke RF
incl stenosis
Further intervent - established guideline
Propylactic sx not recommended
Recommended for symptomatic high grade stenosis
50-99%
Stenting considered high risk candidate
- Anticoagulation
BRIDGE) trial
i. not bridging was non-inferior to bridging for the prevention of arterial thromboembolism
ii. Bridging with LMWH resulted in a nearly three-fold greater incidence of major bleeding
more cautious approach in those at higher risk of periprocedural stroke
(e.g. CHADS2 score >3, recent transient ischaemic attack or stroke, rheumatic heart disease or mechanical heart valve)
DOACs) for atrial fibrillation (i.e. apixaban, dabigatran or rivaroxaban), a temporary interruption of 1–2 days before and resumption 1–3 days after surgery resulted in a low rate of arterial thromboembolism or ischaemic stroke
- Anti platelets
(POISE-2) trial
eceive either aspirin or placebo
No difference in the primary outcome (death or non-fatal myocardial infarction) was found, and aspirin did not result in a significant reduction in stroke
imilar to the bridging of anticoagulation trial discussed above, perioperative aspirin treatment resulted in an increased risk of major bleeding in this study. Therefore, the continuation or initiation of aspirin does not appear to confer protection against perioperative stroke in non-cardiac surgery, non-neurological surgery.
Prevention
- Perioperative management of beta-blocker therapy
hat beta-blockers do not reduce the risk of perioperative stroke in low-risk patients and may increase the risk of stroke if initiated immediately before surgery
POISE trial was a large, randomised trial that randomised patients to extended-release metoprolol or placebo,
metoprolol reduced the incidence of myocardial infarction, it resulted in more deaths and a higher rate of stroke
- Timing of elective
Danish study
risk lowest around 9 months after a stroke
. The decision to delay surgery must be carefully considered and the increased risk of stroke balanced with the risks of delaying surgery (e.g. for cancer).
These results suggest that urgent surgery should not be delayed in patients who have had a recent stroke and, given the concerns about autoregulation, tight haemodynamic control is recommended
Prevention
Management of anaesthesia
Perioperative arterial blood pressure may play an important role in the risk of perioperative stroke although the current literature is conflicting
inally, brain hypoperfusion from the sitting position has been postulated to increase the risk of perioperative stroke, although a review of 4169 patients who underwent shoulder surgery in the sitting position did not find any postoperative strokes, despite frequent hypotension
These data suggest that although intraoperative hypotension may be an important contributor to perioperative stroke, most strokes occur postoperatively
(POISE-3) underway
role of hypotension in patients undergoing non-cardiac surgery
addition, an analysis of the US National Surgical Quality Improvement (NSQIP) database did not show a relationship between type of anaesthesia and postoperative stroke, even with adjustment for multiple confounding variables
Prevention
Management of anaesthesia
Perioperative arterial blood pressure may play an important role in the risk of perioperative stroke although the current literature is conflicting
inally, brain hypoperfusion from the sitting position has been postulated to increase the risk of perioperative stroke, although a review of 4169 patients who underwent shoulder surgery in the sitting position did not find any postoperative strokes, despite frequent hypotension
These data suggest that although intraoperative hypotension may be an important contributor to perioperative stroke, most strokes occur postoperatively
(POISE-3) underway
role of hypotension in patients undergoing non-cardiac surgery
addition, an analysis of the US National Surgical Quality Improvement (NSQIP) database did not show a relationship between type of anaesthesia and postoperative stroke, even with adjustment for multiple confounding variables
Therefore, the choice of anaesthetic modality should be based on other clinical indications, rather than risk of perioperative stroke.
Although these techniques have been shown to detect neurological insults such as stroke during carotid endarterectomy, there is currently no robust evidence that using monitors such as cerebral oximetry prevents perioperative stroke or mortality after non-cardiac surgery.
Postoperative screening and management of perioperative stroke
peak incidence of perioperative stroke occurs 1–2 days after surgery
5% of patients with a stroke presented with mental status changes only with no appreciable deficit, and residual anaesthesia complicated the recognition of deficits.
NIHSS
clinical assessment suggests a perioperative stroke, then immediate imaging should be performed using non-contrast CT or MRI to determine whether an ischaemic or haemorrhagic stroke is the cause
Clinical evaluation should also include measurements of arterial pressure, oxygen saturation, temperature, blood glucose and routine haematological laboratory studies to exclude alternative causes, and a thorough neurological assessment conducted
urther urgent consultation with a stroke neurology service will determine appropriate further management, which may include blood pressure management, thrombolysis or endovascular thrombectomy
able 2The modified National Institutes of Health Stroke Scale (NIHSS), which can be used to assess patients with possible perioperative stroke
A. Level of consciousness questions
0=answers both correctly
1=answers one correctly
2=answers neither correctly
B Level of consciousness commands
0=performs both tasks correctly
1=performs one task correctly
2=performs neither task
C Gaze
0=normal
1=partial gaze palsy
2=total gaze palsy
D Visual fields
0=no visual loss
1=partial haemianopsia
2=bilateral haemanopsia
E F G H
Left arm Left Leg
Right Arm RIght Leg
1 =drift before 10 s
2=falls before 10 s
3=no effort against gravity
4=no movement
I Sensory
0=normal
1=abnormal
J Language
0=normal
1=mild aphasia
2=severe aphasia
3=mute
K Neglect
0=normal
1=mild
2=severe
Outcome
Perioperative stroke is an independent predictor of 30 day in-hospital morbidity and mortality after non-vascular, non-neurological surgery; and is a risk factor for developing cardiovascular and pulmonary complications.
58.5% will either require subsequent assistance with activities of daily living or be incapacitated
NeuroVISION
This study was the first to document an incidence of perioperative covert stroke of 7% (95% CI, 6–9%
perienced a perioperative stroke were more likely to experience postoperative delirium
postoperative cognitive decline
Knowledge gaps in perioperative stroke
First, the pathophysiology of perioperative stroke needs to be better defined, including the mechanisms, timing and modifiers in the perioperative period, which are distinct from non-surgical stroke. The recent data demonstrating the potential role of covert perioperative stroke in postoperative delirium and cognitive function
Post op cognitive dysfxn
Postoperative cognitive dysfunction (POCD) is a possible, subtle decline in cognition present after a patient has recovered from the acute impact of surgery and hospital stay.
*
Postoperative cognitive dysfunction is newly defined as ‘delayed neurocognitive recovery’ if present within 30 days of surgery, or ‘postoperative neurocognitive disorder’ if present within 1 yr after surgery.
*
The inconsistent diagnosis and testing of POCD have led to significant variation between published studies.
*
There is moderate evidence to suggest that altering some aspects of anaesthesia may reduce the risk of developing POCD.
Post op cognitive dysfxn
Postoperative cognitive dysfunction (POCD) is a possible, subtle decline in cognition present after a patient has recovered from the acute impact of surgery and hospital stay.
*
Postoperative cognitive dysfunction is newly defined as ‘delayed neurocognitive recovery’ if present within 30 days of surgery, or ‘postoperative neurocognitive disorder’ if present within 1 yr after surgery.
*
The inconsistent diagnosis and testing of POCD have led to significant variation between published studies.
*
There is moderate evidence to suggest that altering some aspects of anaesthesia may reduce the risk of developing POCD.
Conclusions
One in 10 elderly patients will suffer with POCD at 3 months postoperatively, and for some, this reduced quality of life outweighs the benefits of surgery.
Duration
Cognitive impairment manifests with objective evidence of decline in cognition or activities of daily living. The timing of onset and resolution are specified as:
-Delayed neurocognitive recovery (up to 30 days after exposure to surgery and anesthesia)
-Neurocognitive disorder (NCD; postoperative) diagnosed up to 12 months post-procedure.
●Risk factors for PND
Patient
older age,
preexisting cognitive impairment
(which may be detected by a brief preoperative cognitive screen),
preoperative sleep disruption,
excessive consumption of alcohol,
psychotropic drug use,
medical comorbidities (eg, prior neuronal damage such as stroke or traumatic brain injury, severe vascular disease, diabetes),
and frailty
____________________________________
Procedures
Include cardiac,
major orthopedic,
or emergency procedures,
or prolonged duration of surgery.
Preoperative management
Preoperative management –
We discuss individual risk and
implications of PND during
the informed consent process.
Risk mitigation for all patients
– For all patients we avoid the following
- Excessive anesthetic depth during general anesthesia.
We employ continuous monitoring of the end-tidal anesthetic concentration (ETAC)
to titrate inhalation anesthetic agents.
We also employ either raw or
processed electroencephalography (EEG),
particularly when ETAC monitoring is not feasible
(ie, when inhalation agents are not administered)
and in patients at risk for PND
- Excessive sedation during neuraxial or other regional anesthetic techniques
- Higher doses of intravenous (IV) anesthetic and adjunct agents that may increase risk for PND in patients at high risk.
In particular, we minimize or avoid
benzodiazepines,
opioids, gabapentinoids,
diphenhydramine,
metoclopramide,
anticholinergics (particularly scopolamine),
and agents that can cause serotonin syndrome.
- Extremes of blood pressure (BP; ie, hypotension or hypertension)
Risk mitigation for high-risk patients
We suggest using antiinflammatory agents including acetaminophen, nonselective antiinflammatory drugs (NSAIDS), and selective COX-2 inhibitors as part of a multimodal anesthetic technique, which may decrease PND risk due to opioid-sparing and/or anti-inflammatory properties
We suggest administering an intraoperative infusion of dexmedetomidine or continuing infusion in the postoperative period in high-risk patients admitted to an intensive care unit (ICU) may reduce incidence of delirium
Evidence is insufficient to recommend specific anesthetic techniques (eg, neuraxial versus general anesthesia; total IV anesthesia [TIVA] versus inhalation-based anesthesia; or use of any one inhalation agent) to avoid PND; thus, we select an appropriate anesthetic technique based on other considerations.
Postoperative management
- Employing nonpharmacologic measures such as
cognitive stimulation with
provision of reassurance and reorientation;
maintenance of sensory input (glasses, hearing aids);
early mobilization;
avoidance of dehydration;
and minimizing or avoiding medications associated with delirium risk
while providing excellent control of postoperative pain
- Using a brief postoperative screening tool to detect delirium such as a brief version of the Confusion Assessment Method (CAM) test termed the 3-Minute Diagnostic Assessment (3D-CAM), or the CAM-ICU version
3 Investigating known causes of delirium and treating as appropriate, including medication-induced delirium, substance intoxication or withdrawal.
4 Obtaining a neurology consult in patients with severe or persistent delirium.
Postoperative management
- Employing nonpharmacologic measures such as
cognitive stimulation with
provision of reassurance and reorientation;
maintenance of sensory input (glasses, hearing aids);
early mobilization;
avoidance of dehydration;
and minimizing or avoiding medications associated with delirium risk
while providing excellent control of postoperative pain
- Using a brief postoperative screening tool to detect delirium such as a brief version of the Confusion Assessment Method (CAM) test termed the 3-Minute Diagnostic Assessment (3D-CAM), or the CAM-ICU version
3 Investigating known causes of delirium and treating as appropriate, including medication-induced delirium, substance intoxication or withdrawal.
4 Obtaining a neurology consult in patients with severe or persistent delirium.
