Module 3 Week 6 Flashcards
What is the goal of pre-operative fluid management
It is to provide the appropriate amount of parental fluid to maintain intravascular volume and cardiac preload, oxygen carrying capacity, coagulation status, acid-base hemostasis, and electrolyte balance.
What can make the pre-operative period a challenge
Blood loss, evaporation loss, third spacing, preoperative fluid volume status, and pre-existing disease states
What is the major component of all fluid compartments with in the body
Water
Total body water can be divided into two basic components ______ and _____?
Intracellular and extracellular
What are the major components of the extracellular compartment
Blood volume and interstitial fluid volume
What is the non-cellular component of the blood?
The plasma volume
What is the major difference between plasma and interstitial fluid
Plasma has a higher concentration of protein
What can influence electrolyte balance
Parental fluid administration
What can lead can happen in the perioperative period that can lead to shift in fluid balance
Physiologic changes
What is the recommended period of time for preoperative fasting from clear liquids
2 hours
Balanced salt Solutions have an electrolyte composition similar to what
Extracellular fluid
What is considered extracellular fluid and what classification of fluid do they fall in?
These are hypotonic solutions such as Lactated ringer‘s, Plasma-Lyte, normosol
In vivo ( in the body) what does lactate ringers Metabolize into
It becomes bicarbonate
What kind of solution is normal Saline
It is slightly hypertonic
Why is normal Celine preferred to dilute pack red blood cells
Because it is nearly isotonic
Osmolality of iso tonic solution’s can cause what at the point of injection
Hemolysis
Why does dextrose Function as free water
Because the dextrose is metabolized
In what circumstances is dextrose IV solution used
To correct hyper natremia and to prevent Hypoglycemia and diabetic patients
What are Colloids And why are they used
A colloid is albumin And it is used because it is a larger molecule in weight and remains in the intravascular space longer than a crystalloid
Does albumin affect coagulation?
A minimal effect
Hydroxyethyl starches (HES) interferes with what
With von Willebrand factor, factor VIII, And platelet function
Administration of what after acute blood loss may lead to more rapid improvement of filling pressures, arterial blood pressure, and heart rate
Colloid (albumin)
Postoperatively what rapidly subsides when administration of anesthetics are stopped
Venodilation in my cardinal depression
What is the fluid deficit equation
(Maintained fluid requirement) x (hours since last intake (Npo deficit)) + (unreplaced preoperative external and interstitial) / (third space loss(eg. vomiting, diarrhea))
The fluid infusion rate for normal patient should be set to whiten
It should be set to deliver three 24 times the maintenance rate until the Calculated deficit has been corrected
The onset of surgical stimulation elicits changes in what
Catecholamines, cortisol, and growth hormone
Additional approaches include replacement of Crosoli that the rate proportional to surgical incision exposure is what
4 to 6 mL/kg/hr for bowel resection
What can excessive perioperative fluid administration cause in the G.I. track
The Adema can contribute to an ileus
What is the threshold for weight gain for post operative Procedures that it would be recommended to restrict fluid’s and administer a diuretic
1 kg
What is the first clue that anesthesia providers have about their patient?
History and Physical – which can help identify coexisting diseases and allows CRNA to assess the patient’s anatomy to determine if difficulties with certain anesthetic techniques may arise.
What is the overall goal of pre-op assessment?
Patient safety.
What factors are important to consider during a pre-op assessment?
HCG, smoking status, illicit drug use, medications, allergies, PONV, previous surgeries, medical conditions, anesthesia problems
What labs are important to obtain prior to a surgery?
b-HCG for all child bearing aged women, CBC, glucose (for diabetics, obese, steroid treatment), electrolytes, PT/PTT/INR, CXR, echo
A minimum pre-anesthesia exam must include:
Airway, heart, lung, review of VS, oxygen saturation, Ht/Wt,
What is the anesthesia assessment based on?
The history and type of surgery the patient is having.
What is METS and why is it important to include in a pre-op assessment?
Metabolic equivalents-The ability to attain average exercise levels. 4-5 METS is the equivalent of walking two flights of stairs. If a patient scores <4 METS, they are at increased risk of perioperative complications.
1 MET=
consumption of 3.5mL of O2/mL/min/kg of body weight.
What are two important questions to ask a patient preoperatively about their activity level?
Are you able to walk four blocks without stopping regardless of limiting symptoms? Are you able to climb two flights of stairs without stopping regardless of limiting symptoms.
What is the mallampati exam testing?
Visible structures in the airway.
What can you see in a mallampati 1 patient?
The soft palate, uvula, and tonsillar pillars.
What can you see in a mallampati 2 patient?
Soft palate and uvula
What can you see in a mallampati 3 patient?
Soft palate and base of uvula seen. Very difficult airway.
What can you see in a mallampati 4 patient?
Hard palate only seen. Very difficult airway
What does the mallampati assessment test for?
Potential airway establishment difficulties. It is a predictor of difficulty.
What is the ASA physical status?
A means of communication to anesthesia staff within and among institutions about the physical status of a patient. It is NOT an estimate of anesthetic risks and should remain independent of the proposed surgical procedure. (just because someone is having a Whipple or very difficult procedure, doesn’t mean the ASA should be impacted).
What is ASA class 1?
Patient presents with no organic, physiologic, biochemical, or psychiatric disturbance. Patient is healthy.
What is ASA 2?
Patients have mild to moderate systemic disturbance. Being a smoker places you here. Well-controlled HTN of DM places you here
What is ASA class 3?
Severe systemic disturbance that limits activity. Ex: heart or chronic pulmonary disease, poorly controlled HTN, previous MI, bedridden
What is ASA class 4?
Severe systemic disturbances that is life threatening. Ex: CHF, advanced pulmonary, renal or hepatic dysfunction.
What is ASA class 5?
Moribound patient undergoing surgery as a resuscitative effort despite a minimal chance of survival. Ex: uncontrolled hemorrhage from a ruptured AAA.
What is an ASA class with an E added to it?
Indicates emergency surgery is required. Ex: if a patient cannot sign for consent.
What is patient centered care?
Basing the choice of anesthesia technique or combination of techniques on surgical and patient considerations. Most important considerations are patient safety, the ability of the surgeon to perform the procedure, and patient comfort during and after the procedure.
What should you always have regarding an anesthesia plan?
A plan A AND plan B- which is ALWAYS general anesthesia.
What influences choice of anesthetic technique?
Patient, team, and surgeon preference, coexisting disease (reflux, DM, asthma), site of surgery, body position of patient during surgery, elective or emergent surgery?, increased gastric content, suspected difficult airway, duration of procedure, patient age, anticipated recovery time, PACU discharge criteria.
What does the general anesthesia technique involve?
A loss of consciousness, induction by inhalation or IV, airway instrumented with ETT, LMA, or mask(unsecured) if procedure is short.
What does regional anesthesia or peripheral nerve blocks involve?
RA- Neuraxial anesthesia is provided by placing local anesthesia within the CSF or epidural space. It may be used as primary anesthetic or for postop pain.
Peripheral nerve blocks are provided by placing local anesthetics near peripheral nerves using a needle. Typically used for surgeries of the extremities but may be used as primary or postop analgesia when administered with other techniques like GA.
What does monitored anesthesia care or MAC involve?
Anesthetic drugs are administered to varying levels of sedation, analgesia and anxiolysis as necessary for the procedure. Must prepare to convert to GA if necessary.
If a patient has been rendered unconscious or losses the ability to make purposeful responses during MAC….
The case is now converted to GA regardless of whether or not the airway is instrumented.
Prescription medications can be taken up to _____ hours before anesthesia?
One
Patients are allowed how many mLs of water before surgery?
150mls for adults and 75mls for children.
What is the purpose of fasting guidelines?
Reduce the risk of pulmonary aspiration
Why are you not allowed to chew gum the night before surgery?
Risk of foreign body aspiration
Patients are allowed clear liquids up to ____ hours before surgery.
2
Children can have breast milk up until ___ hours before surgery.
4
Infant formulas and light meals must avoided ____ hours before surgery.
6
Why should you avoid fried or fatty foods 8 hours before surgery?
They prolong gastric emptying time and present an aspiration pneumonia risk.
What are the goals of a preoperative evaluation?
Reduce patient risk and morbidity associated with surgery and anesthesia, prepare the patient medically and psychologically, and promote efficiency and reduce costs
What are the components of a preoperative evaluation?
oReview of medical record
oHistory and physical examination
oObtaining appropriate diagnostic tests and consults
oDevelopment of anesthetic care plan
oEducate the patient about anesthesia and perioperative period
oAnswer questions and obtain consent
Ability to review previous anesthetic records help to…?
Detect presence of a difficult airway, identify a hx of malignant hyperthermia and determine an individuals response to surgical stress and specific anesthetics
What are the four risk factors for PONV after inhalation anesthesia (in adults)?
Female gender, prior hx of motions sickness or PONV, nonsmoking status, and use of postoperative opoids
Name the four predictors of POV in children
Duration of surgery longer than 30 minutes, age above 3 years old, hx of POV in patient or family, and strabismus surgery
What are the components of an airway evaluation?
Examination of oral cavity (including dentition), determination of thyromental disease, assessment of the size of pts neck and potential tracheal deviation or masses, and evaluation of their ability to flex of base of the neck and extend the head
In what patient populations is it critical to assess the cervical spine preoperatively?
Trauma, severe RA, and down syndrome patients
Describe the steps of intubation…
Flexion of the lower neck, extension of upper neck, opening the mouth to insert laryngoscope, and displacing the tongue forward and down into the submandibular space to expose glottis
Which laboratory biomarkers are associated with major adverse cardiac event (MACE)?
BNP, CRP, and N-terminal brain natriuretic peptide
What patient populations may present with atypical signs/symptoms of cardiovascular disease?
elderly, women, and diabetics
What clinical condition (cardiovascular) is associated with a high perioperative risk of MI?
Unstable angina
What is the best predictor of silent ischemia?
Autonomic neuropathy
What ECG pattern is suggestive of a chronic ischemic state?
Strain pattern
What is one of the most important predictors of perioperative risk for noncardiac surgery and helps define the need for further testing and invasive monitoring (the most cost effective and least invasive method for detecting ischemia)?
Exercise tolerance testing
What is the best method for defining coronary anatomy and assessing ventricular and valvular function ?
Coronary angiography
Guidelines support the delay of elective noncardiac surgery for ____ days after coronary balloon angioplasty and ____ days after bare metal stent placement
14; 30
Are preoperative PFTs and chest radiography routinely recommended for all patients?
No, they are not routinely recommended as they have little benefit in predicting pulmonary complications perioperatively
What laboratory levels appear to be associated with increased risk of perioperative pulmonary morbidity?
Reduced albumin level and increased BUN
What types of surgeries are have been associated with the highest risk for postoperative pulmonary morbidity?
Open aortic, thoracic, and upper abdominal surgeries
Name the effects of general anesthesia on the pulmonary system…
Decrease in functional residual capacity, reduced diaphragmatic function –> leading to ventilation/perfusion abnormalities, atelectasis, inhibition of mucociliary clearance, increased alveolar-capillary permeability, inhibition of surfactant production, increased nitric oxide synthetase, and increased sensitivity of the pulmonary vasculature to neurohumoral mediators
What medications should maybe be considered as prophylaxis for the severe asthmatic?
Steroids and bronchodilators
OSA patients are especially susceptible to the respiratory depressant and airway obstructive effects of what medications?
Sedatives, opioids, and inhaled anesthetics both intraoperatively and postoperatively
What is the Purpose of pre-anesthetic evaluation?
ppt
Tool to reduce anesthetic risk and morbidity
Promote efficiency and reduce cost
Medico-legal document
Mandated by Joint Commission for the Accreditation of Healthcare facilities
Part of the American Society of Anesthesiologists (ASA)
The preoperative assessment allows CRNAs to…
ppt
Communicate with the team
Tailor anesthetic care plan to individual needs
Identify if surgery will proceed, be delayed, or be deferred
Aids in optimization of comorbid diseases
Identify pertinent necessary preoperative testing
Educate our patients about the anesthesia process
Establish informed consent
What are the Goals of Preoperative Evaluation:
ppt
- Reduce patient risk
- Morbidity of surgery
- Promote efficiency and reduce costs
How can improve patient outcome from anesthesia?
ppt
History and physical examination
Laboratory tests and consultations
Anesthetic and care plan
What are the Standards for All Patients Receiving Anesthesia Care?
ppt
Review the available medical record
Interviewing and performing a focused examination of the patient to
Discuss:
Medical history, including previous anesthetic experiences and medical therapy
Assess aspects of the patient’s physical condition that might affect decisions regarding perioperative risk management.
Standards for All Patients Receiving Anesthesia Care (ASA 2010)
ppt
- Ordering and reviewing pertinent available tests and consultations as necessary for the delivery of anesthesia care
- Ordering appropriate preoperative medications
Ensuring that consent has been obtained for the anesthesia care - Documenting in the chart that the above have been performed
What are the components of pre-anesthetic evaluation?
ppt
1. History: Current & past medical history Family history of anesthesia problems, ie, Malignant hyperthermia Medications Previous Surgeries Anesthetics Allergies NPO status
- Physical exam:
- PreopVital signs
- Airway
- Neurologic
- Heart
- Lungs
- Extremities
- Organ systems
- Focused areas
- Laboratory and diagnostic testing and evaluation
- ASA classification number
What are the most important assessors of disease and risk?
ppt
History and physical exam.
Factors to Consider for anesthesia evaluation.
- Coexisting disease
- Site of surgery
- Position during surgery
- Risk of aspiration
- Age of patient
- Patient cooperation
- Airway management
- Coagulation status
- Previous response to anesthesia
- Preference of patient
- Elective or emergency
- Recovery time
- Post anesthesia discharge
What risks are associated with anesthesia?
-Potential difficulty for adequate ventilation/intubation
-Induction/emergence is “stressful” Maintenance of anesthesia is associated with variable degrees of stimulation, fluid shifts, & blood loss
-Anaphylactic reactions to medications may occur
-Injuries may be incurred such as airway trauma during
laryngoscopy/neuropathy from improper patient positioning
-LIKE FLYING A PLANE, TAKE OFF AND LANDING IS THE MOST DANGEROUS
New approaches to preoperative anesthesia evaluation?
-Pre-op clinics
-Decrease in same day surgical cancellations
-Improve in operating room efficiency
-Cost effective
-Computerized data accessible by all anesthesia providers prior to procedure
-Emergency procedures: hand written anesthesia
evaluation
How to do to a healthy pre-op patient assessment.
-Indication for the surgical procedure
-Current Medications/Allergies
-NPO status
-Thorough history and physical
-Systems approach:
Airway, Malampatti classification
Pulmonary
Cardiovascular
Neurologic
Endocrine
Renal
Hepatic
Gastrointestinal
-Response to previous anesthetic, ie, Difficult Airway, Malignant Hyperthermia, Bleeding (watch out for Red heads)
What is the purpose of ASA’s Fasting Recommendations
Reduce the risk of pulmonary aspiration
ASA fasting recommendation what is considered as a light meal?
toast and clear liquids
What is considered as a heavy meal?
fried and fatty foods.
What is the recommended fasting time in hours for clear liquids
2 hours
What is the recommended fasting time in hours for breast milk
4 hours
What is the recommended fasting time in hours for infant formula
6 hours
What is the recommended fasting time in hours for infant formula for neonates
4 hours
What is the recommended fasting time in hours for non-human milk
6 hours
What is the recommended fasting time in hours for light meal
6 hours
What is the recommended fasting time in hours for heavy meal
8 hours
What is considered as History of problems with anesthesia.
Malignant hyperthermia, Allergic reactions, Post-operativenausea and vomiting, Difficulty with intubation,
Unplanned/prolonged postoperative
intubation.
category “ASA VI stands for
the brain-dead organ donor
What does E” denotes for ASA category
Emergency surgery
ASA Physical Status class 1
Normal healthy patient. No organic, physiologic, biochemical or psychiatric disturbance
ASA Physical Status class 2
Mild to moderate systemic disease that is well controlled and causes no organ dysfunction or functional limitation, that is, treated hypertension. Example, Current smoker Social alcohol drinker Pregnancy Obesity Well-controlled DM/HTN Mild lung disease
ASA Physical Status class 3
Severe systemic disease of at least one organ system that does cause functional limitation, that is, stable angina,Example
Poorly controlled DM/HTN
COPD
Morbid obesity (BMI ≥40)
Active hepatitis, alcohol dependence or abuse
Implanted pacemaker
Moderate reduction of ejection fraction
ESRD undergoing regularly scheduled dialysis
Premature infant PCA < 60 weeks
History (>3 months) of MI, CVA, TIA, or CAD/stents
ASA Physical Status class 4
Severe systemic end-stage disease of at least one organ system that is life threatening with or without surgery, that is, congestive heart failure or renal failure
For example Recent (< 3 months) MI, CVA, TIA, or CAD/stents
Ongoing cardiac ischemia or severe valve dysfunction
Severe reduction of ejection fraction
EF, 30% is ASA 3
EF, 20% is ASA 4
Sepsis
DIC
ARD
End stage renal disease (ESRD) not undergoing regularly scheduled dialysis
ASA Physical Status class 5
Moribund patient who has little chance of survival but is submitted to surgery as a last resort (resuscitative effort) that is, ruptured aortic aneurysm
For example, Ruptured abdominal/thoracic aneurysm
Massive trauma
Intracranial bleed with mass effect
Ischemic bowel in the face of significant cardiac pathology
Multiple organ/system dysfunction
ASA Physical Status class 6
A declared brain-dead patient whose organs are being removed for donor purpose. For example,
Components of Physical examination
-Measurement of Preoperative Vital signs: (BP, HR, RR, T, SaO2)
-Inspection of the airway
Loose, chipped teeth
Caps
Dentures
Prominent upper incisors
TMJ
Neck ROM
-Auscultate heart and lungs
-Inspect extremities
-Brief neurologic exam
Mallampati classification
Relationship between the size of the base of the tongue and the rest of the structures of the pharynx:
Class I: Mallampati classification
pillars, uvula, soft & hard palate
Class II: Mallampati classification
uvula, soft & hard palate
Class III: Mallampati classification
: soft & hard palate visible
Class IV: Mallampati classification
only hard palate visible
Ingredients of propofol
Egg lecithin emulsion
10% soy bean oil, 2.25% glycerol & 1.2% egg phosphatide extracted from yolk
Physical Examination: How to Evaluate the airway
-Thyromental distance Measure between the edge of the mandible and the cricoid cartilage: should be > 6 cm -Neck mobility Flexion Extension -Observation of patient, assess for: Short neck Obesity Micrognathia (restricts oral axis alignment), jaw is undersized. -Ability to open mouth
Egg allergy-Cross-sensitivity reaction to Propofol (Diprivan)
Allergy usually to egg albumin in egg white!!!!!
Propofol contraindicated in patients with egg allergy
Objective of Obtaining Anesthesia Informed Consent
-The subject has knowledge and comprehension of anesthesia procedures”
“-Risks and benefits have been explained”
“-Pt’s questions have been answered
-Risks,benefits,alternatives explained
Procedure without consent :
Assault and Battery
When to take two-physician emergency consent
- If the patient is a Minor
- Incompetent
- Unconscious patient
practice advisory for anesthesia evaluation
Preoperative tests should not be ordered routinely!!!
Preoperative Testing: 12-lead EKG, Indication
—-Any patient with a previously undiagnosed murmur
——–Asymptomatic patients > 50 y/o or any age with one of the following:
CAD, CVA, or PVD
Creatinine >2
DM
High risk surgery or vascular surgery
Chest pain/ischemia
Prior coronary revascularization/hospitalization for cardiac causes
Pre-op ECHO indication
- Any identified EKG abnormality should be followed up by an echo
- Patients with current or poorly controlled heart failure
- Prior heart failure and dyspnea of unknown origin
Stress testing,Indication
- Patients with intermediate pretest probability
- Change in clinical status of patient with suspected or proven CAD
- Proof of ischemia prior to revascularization
- Evaluation of adequacy of medical therapy
- Evaluation of exercise capacity when subjective assessment unreliable
Exercise stress test
- Exercise stress test has a specificity of 69% for predicting post-op cardiac events
- Accurate test results when patients can exercise to 85% of their target HR
- Often used in combination with echocardiogram for patients with significant EKG abnormalities to detect wall abnormalities
Ideal BP for surgery
SBP BELOW 140
DIASTOLIC BP BELOW 90
Elective surgery should be delayed for BP
—if if SBP >200 mm Hg or DBP > 115 mm Hg- until BP is less than 180/110 mm Hg
Which Anti-hypertensives should be delayed on the day of surgery
ACEI (Angiotensin Converting Enzyme)
ARBs (Angiotensin Receptor Blockers)
Pharmacologic stress test
——-Provides the more accurate prognostic information than exercise stress test
———-Used for patients who:
Cannot exercise
Have pacemakers
Have marked bradycardia
Are on high-dose beta blockers
Can also be used in combination with echocardiogram to detect wall abnormalities
Pre-op Testing: indication for Chest X-ray
–Consider in pt’s ≥ 50 y/o:
–Hx of lung disease
Asthma,
COPD
——-Active pulmonary condition
URI
Pneumonia
Pulmonary edema)
——–Having intrathoracic surgery
Smokers
Cardiac disease
Indication for pre op Complete blood count (CBC)
- Any procedure @ risk for blood loss > 500 cc
- Extreme age (neonates, adults age ≥ 75yr)
- Medically ill patients
- Anticoagulant/corticosteroid use
- Hx anemia, bleeding, hematologic disorders, infection
- Those receiving chemotherapy/radiation treatment
T & S AND T&C
TYPE AND SCREEN ,TYPE AND CROSS
T & S probability of intraop transfussion
T & C expected to require intraop transfussion
T & S (7 days)
T & C (2 days)
Pre-op Human chorionic gonadotropin (HCG) testing
- Exclusion criteria:
- Hx of total hysterectomy
- Menopause (1yr without menses)
- Bilateral tubal ligation
———Usually everyone under the age of 50yo
JMH guidelines for pre-op HCG testing
- Any female patient child-bearing age who suspects pregnancy
- Minors
- Should be done in minors capable of conceiving (Minor patients and their guardian should be notified that a pre-operative pregnancy test is being performed, but a POSITIVE result should be reported only to the patient. -The patient should be strongly encouraged to discuss this result with her guardian.
- Any patient undergoing a hysterectomy or gynecological procedure
- Any childbearing woman under 50 is mandatory unless patient had a tubal ligation, hysterectomy or no menses for one year after 50.
MEDICATIONS TO CONTINUE PRE-OP
- Cardiac/BP meds (statins, BB)
- Meds for asthma/COPD
- GERD meds
- Thyroid meds
- Psychiatric meds
- Narcotics
- Bronchodilators/Steroids
- Seizure meds
- Birth control pills
MEDICATIONS Should be held or adjust dose:pre-op
- Oral hypoglycemics
- Short acting insulin
- ACE inhibitors
- Diuretics (except HCTZ)
- Viagra
Anticoagulants dosing for pre-op
NSAIDs- stopped 2 days before surgery
Warfarin- stopped 5 days before surgery
Aspirin (ASA) and surgery
- Typically stopped 5 days before surgery EXCEPT:
- In patients who have had a DES placed less than 12 months ago
- In patients who have had bare metal placement less than a month ago
- ASA is usually continued in patients with any type of stent placed during any given time frame
Thienopyridines:INCLUDE Clopidogrel/ticlopidine
ppt
-Clopidogrel- stop 7 days before surgery
-Ticlopidine- stop 14 days before surgery
EXCEPT:
In patients who have had a DES placed less than 12 months ago
In patients who have had bare metal stent placement less than a month ago
Ephedra HERBAL (diet aids, antitussive) can cause
- Sympathetic stimulation,
- ↑ HR, BP
- Dysrhythmias, MI, stroke
St. John’s wort ,HERBAL
- Depression
- Anxiety
- Increases drug metabolism induction, cytocrome P450, decrease drug levels (ie, digoxin)
Ginseng (stress)-HERBAL
- Hypoglycemia,
- Inhibits PLT aggregation
- Increase bleeding
Patients anesthetic history:
- Difficult airway, examination of oral cavity and dentition
- Malignant hyperthermia
- Prolonged response to drugs, ie, patient states I took a long time to wake up in my last anesthetic.
- Current medications, over the counter and herbal products
Screening evaluation for the Pulmonary system:
---------History: Tobacco utilization Shortness of breath Cough Wheezing Stridor Snoring or sleep apnea Recent history of an upper respiratory tract infection
Preoperative Predictive Pulmonary complications:
- Thoracic and Upper Abdominal Surgery
- Duration of Anesthesia
- Chronic Cough
- Unexplained Dyspnea
- Exercise Tolerance
- Wheezing/Asthma
- Tobacco Utilization
Guidelines for perioperative management of patients with obstructive sleep apnea
–ASA Guidelines
CPAP
Sensitivity to respiratory depressant effects of drugs
–Determine if noninvasive approaches for performing the surgery would reduce the need for postoperative opioids
–Discuss if it is feasible to perform the surgery under neuraxial, regional or local anesthesia to decrease the amount of anesthesia or opioids needed
–Determine if NSAIDs are acceptable for postoperative analgesia
–Discuss whether outpatient surgery is a safe option
–Determine if the patient will be able to use CPAP postoperatively
–Determine if Postop admission to ICU is needed for a first time user of CPAP
Preoperative Evaluation of Neurologic Function:
- Mental Status
- Intracranial pressure
- Cerebral vascular disease
- Seizure history
- Peripheral neuropathy
Preoperative cardiovascular Evaluation:
- Hypertension
- Angina
- Congestive Heart Failure
- Auscultation (heart murmurs, carotid bruits)
- Cardiac rhythm
- Peripheral Pulses
Preoperative Cardiovascular Testing:
—Exercise tolerance
——–Cardiovascular tests
Electrocardiography
Echocardiography
Coronary angiography
Preoperative Evaluation of Diabetes Mellitus
- Silent Angina
- Myocardial Infarction
- Congestive Heart Failure
- Peripheral neuropathies
- Autonomic Neuropathy
- Hemodynamic instability
- Gastroparesis
Suboptimal glucose control
Hemoglobin A1C>6-8%
Electrolyte abnormalities
Ketonuria
Ischemic Heart Disease (CAD),GOALS FOR EVALUATION
- Identify heart disease risk
- Identify severity of heart disease
- Determine need for perioperative testing
- Modify risk for adverse perioperative event
With h/o steroids use how to treat patients with minor surgical risk
hydrocortisone 25mg iv pre-op,can restart ususal dose day after surgery
With h/o steroids use how to treat patients with intermediate surgical risk
ppt
hydrocortisone 50-100 mg iv pre-op, / 25 mg iv/po qhrs x 3 doses
With h/o steroids use how to treat patients with majorr surgical risk
ppt
hydrocortione 50-100 mg iv pre-op, 50 mg iv/po q8hrs and taper over 2-3 days
What are S/S of CAD
Chest pain SOB/dyspnea What do the labs show What does the EKG show Cardiac clearance
What are Long-term CAD risk modifications
Statins
Aspirin
Exercise
Diet adjustment
in cardiac pt when should elective SX be held
- Those with bare metal stents placed within the last 30 days
- Those with drug-eluting stents (DES) placed within the last 12 months
- Premature discontinuation of dual antiplatelet therapy could result in
- Stent thrombosis
- MI
- Death
what is the goal of preoperative evaluation
-to identify/minimize effects of heart failure
What do you want to evaluate in CHF pt pre operatively?
Recent weight gain? SOB/fatigue? Orthopnea/nocturnal cou-gh? Peripheral edema/JVD? S3/S4? Tachycardia? Ascites?
what are the stages of heart failure
Class I- No limitation of physical activity
Class II-Slight limitation of physical activity.
Class III-Marked limitation of physical activity
Class IV-Unable to carry out any physical activity without discomfort
what are cardiac considerations for sx pt
-Angina
unstable ↑ risk perioperative MI
chronic stable not shown to ↑ risk MI
Pacemaker and/or AICD
Clinical Predictors of Increased Perioperative Cardiovascular Risk
- Unstable coronary syndromes
- Decompensated heart failure
- Significant arrhythmias
what is the MET questionnaire
questions regarding exercise testing, exercise prescription, and evaluation
what questions do you ask in the Metabolic Equivalent (MET) questionnaire
1 METs
Eat, dress, us>/= 10 METs
Strenuous sports
(swimming, singles tennis, football, basketball, skiing)
e the toilet,
walk indoors, light housework,
walk a block or two on level ground at 2 – 3 mph
4 METs
Climb a flight of stairs,
walk on level ground at 4 mph, run a short distance,
do heavy housework,
moderate recreational activities (bowling, doubles tennis, golf, dancing)
on the Metabolic Equivalent (MET) questionnaire what number do you have to be worried about
Any thing under then 4
what is the Cardiac evaluation for noncardiac surgery
step I - need emergency surgery
step II-active cardiac conditions
step III-low risk for sx
step IV-good function capacity
Postoperative pulmonary complications
Risk factors: Cigarette use current or >40 pack years Age 70 or > COPD BMI of 30 or Mets <4 Undergoing neck, thoracic, upper abdominal, aortic or neurologic surgeries
what can help an asthmatic prior to surgery ?
breathing treatment
what are symptoms of COPD
Symptoms include: Dyspnea Coughing Wheezing Changes in sputum amount, or color? Barrel chest? Purse-lipped breathing? SaO2? Chest x-ray?
what should you postpone surgery in pt with recent Upper Respiratory Infections (URI)
Patients at risk for laryngospasm bronchospasm
what should you assess in pt with recent Upper Respiratory Infections (URI)
Recent antibiotics?
Does patient have fever?
Does the patient have a productive cough?
how is Pulmonary hypertension (PHTN) defined
as a mean pulmonary pressure >25 mm Hg or pulmonary artery occlusion pressure < 15 mm Hg
what are Increased risk for perioperative morbidity/mortality with moderate-severe PHTN
Dyspnea at rest?
Hypoxemia?
Right-sided heart failure?
Split S2?
Direct and “second-hand” exposure to tobacco increases the risk of postoperative what complications
Desaturation
Severe coughing
Hypertension
Ischemia
Smokers have increased of what?
Sputum production,
↑ Airway reactivity,
↓Oxygenation
why should Elective surgeries should be postponed until patient is “euthyroid” when a patient has thyroid complications
Surgery can precipitate myxedema coma/thyroid storm
What are the components of intracellular fluid
Potassium, phosphate, magnesium
How much of total body water is intracellular fluid (TBW)
2/3
Are Na-k-ATP pump located inside or outside the cell Membrane
Inside the cell membrane
How much Total body water does extracellular fluid contain
1/3
How is extracellular fluid divided
It is divided into intravascular (plasma) and interstitial fluid
Extracellular fluid has High concentrations of what
Na (cations) and cl (anions)
Where is interstitial fluid located
It is fluid within the tissues
What does intracellular fluid compartments contain
It is characterized by high potassium (cations), phosphate (anions), and magnesium concentration
What are starling forces
Starling forces determine the motion of the fluid across capillary membrane
What are the four forces that govern fluid dynamics
Capillary pressure
Isf pressure
Isf colloid osmotic pressure
Plasma colloid osmotic pressure
Why is osmotic pressure significant
It pulls fluid into the cell, it is determined by plasma protein concentration and serves to maintain fluid volume within the intervascular space
What can alter fluid and electrolyte balance of patients during the pre-operative.
Illness, surgery and anesthesia
Preoperative have a bulimia and electrolyte abnormalities are at least in part an ________________ Phenomenon related to bow preparation and pre-operative
Iatrogenic
Surgery can lead to ____________ And a need a replace Fluids or blood
Hemorrhage
What is redistribution of fluid from intravascular space into the interstitial space
“Third spacing”
Which to a lecture lights are cat ions and where are they located
Sodium is a major Cariant in the extracellular fluid
Potassium is a major cat ion it and intracellular fluid
Where does protein have the highest concentration intracellular fluid or extracellular fluid
Intracellular (ICF)
Where is Chloride located
It is in the extracellular fluid
What is the treatment for acute hypocalcemia?
Treatment of acute hypocalcemia involves the infusion of calcium salts. Calcium chloride is the most bioavailable parenteral preparation of calcium & results in rapid correction of hypocalcemia.
What is the most common cause of hypercalcemia?
Primary hyperparathyroidism. Malignancy being the second most common cause.
How do we treat hypercalcemia?
Volume expansion with NS & loop diuretics
What is the second most abundant intracellular cation second only to potassium?
Magnesium
30% of alcoholics admitted to hospital have _____ (hyper/hypo) magnesemia?
hypomagnesemia
What is the treatment for hypomagnesemia?
Administer 1-2 g of magnesium sulfate over 5 minutes while ECG is monitored followed by 1-2 g/hr of magnesium sulfate
What are the clinical manifestations of hypermagnesemia?
Clinical manifestation: 3-5 Flushing, N/V 4-7 Drowsiness, ▼ of deep tendon reflexes 7-10 Loss of patellar reflex 10-15 Respiratory paralysis, coma 15-20 Cardiac arrest
What are the causative factors for hypermagnesemia?(serum magnesium >2.5 mg/dL)
Renal failure, excessive magnesium administration, adrenal insufficiency
What are the three principle purposes of parenteral fluid administration?
Maintenance fluids, replace fluids loss as result of surgery and anesthesia (1:3 ratio for blood loss), correction of electrolyte disturbances
Most commonly used fluid in the surgical setting with a similar concentration to ECF?
Crystalloids
Crystalloid or colloid…
Which is better for volume expansion?
Colloid
What is the first choice for volume resuscitation of trauma patients with head injuries?
Isotonic crystalloid solutions
What is a possible adverse effect of giving NS with large volume resuscitation?
hyperchloremic acidosis
What is a possible adverse effect of giving LR with large volume resuscitation?
metabolic alkalosis from lactate being metabolized into Bicarb
What solutions can be given with PRBCs?
NS & P-Lyte
If hypernatremia is accompanied by volume depletion, which do you treat first?
The volume deficit with isotonic fluids and THEN treat the hypernatremia with hypotonic fluids.
what is the principle electrolyte in intracellular fluid?
Potassium, 98% of K is located in the ICF.
K abnormalities can be the result of abnormal total body K stores and…..?
an imbalance between the normal ICF and ECF K concentrations.
Which electrolyte imbalance creates disturbances with resting membrane potentials?
Potassium. Abnormalities cause cardiac dysrhythmias and peripheral muscular abnormalities
Hypokalemia is defined as a serum level
3.5
Maximum rate of Potassium replacement to avoid hyperkalemia is….?
10-20mEq/hr
Would you most likely cancel a case as a result of hyperkalemia or hypokalemia?
HYPERkalemia as it is harder to treat.
Should you replace potassium with or without chloride and with or without dextrose for treatment of hypokalemia? Why?
WITH chloride (to enhance the kidney’s ability to retain K) and withOUT dextrose (as insulin will draw K into the INTRAcellular compartment).
Do anesthetic agents, such as succinylcholine, increase or decrease potassium?
increase
mild hyperkalemia leads to…
Peak T waves and prolonged PR interval
Moderate hyperkalemia leads to….
Widened ORS, loss of P wave, and ST elevation
Severe hyperkalemia leads to……..
sine wave, Vfib, astystole
How can we treat hyperkalemia by SHIFTING potassium stores instead of losing total potassium?
administer insulin and glucose, administer bicarb, hyperventilate, beta stimulation via albuterol,
How can we treat hyperkalemia by decreases total K stores?
kayexelate and K-wasting diuretics
Does acidosis increase or decrease serum K? Alkalosis?
Acidosis= increased serum K; Alkalosis= decreased serum K
______% of Ca is found in bones
99%
what faction is the most clinically significant form of Ca?
Ionized Ca
What are the most likely causes of HYPOcalcemia?
hyperventilation and changes in pH; also caused by massive transfusions of citrated blood
For iconic pressure it is important to have higher or lower protein
Higher protein is important
