Anesthesia Principles and Practice I: Lecture 9 - Geriatrics Flashcards
(31 cards)
Geriatric Anesthesia
Folks >65 years represent the fastest growing segment of population
By 2040
24% of Population
45-50% of Healthcare related expenses
½ will require surgery before death
3X higher risk for perioperative Death
Ethics- Rationale for Surgery
Save a degree of Function
Relieve Pain
Improve Quality of Life
Assuage suffering
Maintenance of Autonomy is a top priority
↓Fear of Dying than younger patients
↑ Desire to preserve activity
Ethics
Capacity
Stopping psychotropic meds
Time of Day is important for important discussions
Many have worse cognition at night
Capacity- “A functional determination that an individual is or is not capable of making a medical decision within in given situation.”
Competency- “The ability of an individual to participate in legal proceedings”
Determined by a judge, never a medical provider.
Informed consent- “the systematic approach to patient education and medical decision making regarding a particular treatment of procedure”
LOOK UP MORE ABOUT THESE DIFFERENCES!!!
When is it worth further investigating a patient’s decision-making capacity?
Inability to voice and opinion
Blanket acceptance or refusal of care
Absence of questions about treatment being provided
Excessive of inconsistent reasons for refusing care
New inability to perform activities of daily living
Hyperactivity, disruptive behavior, or agitation
Labile emotions or Affect
Hallucinations
Clinical intoxication
LOOK UP MORE ABOUT LEGAL GUARDIAN, WHO CAN SIGN IF THEY ARE PRESENT THEMSELVES!!!
How does the patient prove capacity?
Understanding of information relevant to the discussion in question.
Ability to weigh risks and benefits, and to asses alternative options.
Communicate clearly with medical providers about the decision in question and verbalize the ultimate decision.
Consistency of logic and decision-making throughout the encounter.
Perioperative Advance Directives: DNR in the Operating Room
Only 40% of patients who undergo CPR in hospital will have return of spontaneous circulation.
Only 10% survive until hospital discharge.
TV shows do not convey this reality
Policy developed that we should preserve the life of all patients.
This has resulted in the crazy situation where resuscitation is the sole medical intervention requiring a written order/consent not to perform.
Of the 10% that survive until discharge, only 25% (so 2.5% from the starting group) survive in excess of 5 years. Most of those will be confined to chronic care facilities and/or have neuroligc disabilities.
More DNR
INDICATIONS FOR DNR
When a patient makes an informed decision to decline CPR
In situation CPR is known to be ineffective
Cardiac arrest from traumatic injuries.
When arrest is attributable to anesthetic causes, recovery rate can be as high as 92%
Many resuscitative measures are a part of anesthesia
Intubation, ventilation, inotropic support
Calculation of Risk benefit is therefore different
DNR: Two Current Approaches
The DNR List (Most Common)
* Allows patients to select interventions they will allow
Intubation
Medications
Chest compressions
Defibrillation
* Pro: Easy to follow
* Cons:
Does not explore what sort of result is important to Patient
Rigid
Goal-Directed
* Discuss patient’s detailed goals of care
Allow physician to determine the best way of getting to those goals.
Gives flexibility for anesthesia and surgical teams.
If goal is to not have severe cognitive deficit
Brief resuscitation might be allowed
Extensive interventions to prolong life but result in anoxic brain injury would be avoided.
Decision tree
What options do the patient and surgical/anesthesia/nursing team have?
Keep in place during surgery, cancel, or suspend directive for a specified amount of time. Procedure or goal directed directive can be kept in place.
What if a consensus cannot be reached?
Patient or POA has the final word
What resources are available?
Palliative care or ethics consults can be very valuable.
What have professional organizations said?
ACS, ASA, AORN all say it is inappropriate to automatically suspend a patients DNR
Required reconsideration is the standard of care.
Age and Perioperative Risk
Older patients have ↑ risk of periop M&M.
Patients >80 yrs of age are classified as ASA 2 by ASA Physical status scale.
Parallels between old and young: Elderly and Infants
↓ ability to increase HR in response to hypovolemia, hypotension, or hypoxemia
↓ Lung Compliance
↓ Arterial oxygen tension
Inability to cough (CANT MAKE SECRETIONS??? LOOK UP)
↓ Renal tubular function
↑ susceptibility to hypothermia
Prone to pressure ulcers
Physiologic Changes- Nervous System
Gross Anatomical Changes
↓ In brain Size and neuronal density
Widening of sulci and ventricles
… smaller amount of drug needed because “less space” needed to be acted on
Pharmacodynamic Sensitivity
↑ Sensitivity to propofol, fentanyl, midazolam
… dont need to pretreat with opioids and make them work for pain medications intraop
↓ in cholinergic receptor activity may explain ↑ side effects to meds that act there
Diphenhydramine, Meperidine, Scopolamine
↓ Ventilatory Responses
Response to hypercapnia and hypoxemia
Effects of opioids, benzos, VA are exaggerated
Nervous System Changes
Cerebrovascular changes
Autoregulation is impaired, ↓ response to BP changes, hypoxia, hypercapnia
Higher Pain Threshold
↓ in myelinated fibers and altered pain perceptions
May prolong diagnosis of painful pathophysiology like appendicitis etc.
Post-op Delirium
Post-op delirium and Post-op cognitive defects are far more common
Undiagnosed multi-infarct dementia or neurodegenerative disease may be present
Cardiovascular System Changes
BP Lability
Hardened arteries lead to hypertension
Intraop hypotension is very common and worsened by
Vasodilation of anesthetics
Sympatholysis from neuraxial anesthesia
↓ Venous return from insufflation
… have a drip of Neo ready to go
A progressive decline in baroflex sensitivity and autonomic responsiveness
Increased vagal tone and decreased sensitivity of adrenergic receptors
Decline in heart rate
More dependent on synchronous atrial contraction for ventricular filling
Autonomic Changes
“dysautonomia of Aging”
Beta receptors are impaired
↓ ability to compensate CO with HR
More dependent on vascular tone and pre-load
LV Hypertrophy
↑vascular resistance ↑ LV work
Impaired diastolic filling/dysfunction found in ½ of patients older than 65 diagnosed with CHF
Systolic HTN more common
Fibrosis of conduction system
Increased chance of arrythmias, especially Afib and flutter
More dependent on atrial kick for filling in diastole, even brief atrial arrythmias can cause sever hypotension. Diastolic dysnfunction ↑risk of Pulmonary Edam with fluid admin
Respiratory Changes
Stiffening of Chest Wall
↓ elasticity of lungs
↑ work of breathing = Can cause respiratory failure
↑ closing capacity leads to small airway closure
↑ V/Q mismatch (↑dead space)
↓ FEV and Vital Capacity
↓ responsiveness to CO2
Impaired pharyngeal function = Obstruction, dysphagia (happens much easier)
↓ respiratory muscle strength and cough mechanism
↓ PaO2, ↑A-a gradient leads to hypoxemia
Undiagnosed COPD and OSA may present
More likely to obstruct/not tolerate MAC
Incentive Spirometry can be very helpful pre-operatively
Renal Changes
↓ GFR, Creatinine Clearance, and Renal reserve
Results in increased plasma [ ] of renally excreted compounds
Prolonged DOA
Can’t dilute urine as well
Difficulty handling fluid bolus
More likely to have nephrotoxic effects from NSAIDs, IV Contrast, Aminoglycosides etc. (LOOK UP THESE DRUGS MORE!!!)
Hematological System Changes
Anemia d/t Iron Deficiency, chronic disease, malnutrition, or bone marrow malfunction
Neuroendocrine Changes
Aging and stress-related neuroendocrine dysregulation can combine to affect immune function.
This can result in worsened immune function ↑ risk for inflammatory disease.
Pharmacokinetic Changes
Little bit goes a long way is big take away from this slide.
Pre-Anesthesia Consult
Frailty has a stronger association with poor outcomes than age alone.
Nursing Home resident are at a much higher risk of poor outcomes.
What are the goals of treatment?
What are the risks of surgery?
Are they likely to return to good function?
Review Advance Directives
Nutritional Risk Score Tool
Albumin level less than 2 is considered malnurished (LOOK INTO MORE!!!)
Assessment for Frailty
Defined as “an aging-related syndrome of physiologic decline and reduced tolerance to medical and surgical interventions.
Weakness and fatigue
Medical Complexity
↓Physiological reserve
Periop Neurocognitive Disorders
Post-Op Delirium- 2 kinds
Transient agitation and delirium right after GA
Persistent/recurrent delirium later in post-op period
Emergence Delirium- Brief, may see pronounced during Stage II in recovery from GA
Persistent/recurrent- can occur after any surgery and anesthetic technique. Patients may fluctuate between hyperactive/hypoactive or exhibit one or the other subtype
Hypoactive- Excessive somnolence/altered mental status
Hyperactive- Overt agitation, hyperexcitability, disinhibition, crying, restlessness, and confusion.
KNOW THIS LIST!!!
Post-op Neurocognitive Impairment
Delayed Neurocognitive Recovery
Persisting up to 30 days post procedure, seen in 17-43% of post-op adults. Much higher in the elderly.
Neurocognitive Disorder
Cognitive decline that persists after 12 months.
Older Age (>65 y) and Pre-existing Cognitive Impairment are biggest Risk Factors
May be >80% in critically ill elderly.
Other risk factors
Preop Sleep Disruption
Excessive EtOH consumption, polypharmacy/psychotropic drug use
Severe Vascular Disease, Diabetes, prior neuronal damage (TBI, Stroke)
… remember 1/4 of a MAC induces amnesia
More likely after cardiac (26-52%) and major ortho surgery (17-31%). Major head and neck surgery (12-36%) and colorectal surgery (8-54%).
Prevention
Avoid excessive Depth during GA
Avoid low BIS and burst suppression (can monitor EMG too (high score on EMG is they need more anesthesia))
Processed EEG associated with 30-38% ↓in postop delirium
Avoid excessive sedation during regional anesthesia
Avoid extremes of BP
Keep MAPs >65 mmHg and Systolic >100 mmHg
Avoid Cerebral Desaturation
Cerebral Oximetry discussed in I&M. I think.
OG thought was that Neuraxial w/ sedation resulted in less delirium than GA
These studies have not been able to be reproduced.
Was also thought TIVA ↓Risks vs Inhaled Agents.
Biggest study to date found similar rates of postop delirium
