PREOPERATIVE EVALUATION AND PREPARATION (based on T) Flashcards
What organization developed the Basic Standards for Preanesthesia Care?
The American Society of Anesthesiologists (ASA), adopted by the Philippine Society of Anesthesiologists.
What is the responsibility of the anesthesiologist in preanesthesia care?
Determining the patient’s medical status and developing an anesthesia care plan.
What should the anesthesiologist review before anesthesia?
Medical records, patient history, physical exam, relevant tests, and consultations.
What is included in the patient interview for preanesthesia care?
Discussion of medical history, past anesthetic experiences, surgical history, and medical therapy.
Why is physical examination important in preanesthesia evaluation?
To assess perioperative risk and management, including airway assessment and spinal/epidural feasibility.
What tests or consultations should the anesthesiologist review?
Pertinent available tests and necessary consultations for anesthesia care.
What medications may be ordered preoperatively?
Preemptive analgesia and antibiotics.
What should be included in the informed consent for anesthesia?
The anesthetic plan and risks, including the possibility of death.
What is documented in the chart before anesthesia?
Medical status assessment, anesthesia plan, informed consent, and preoperative evaluations.
What are the cornerstones of preoperative evaluation?
History and physical examination.
What is the purpose of preoperative evaluation?
To identify patients who may benefit from medical optimization or surgery postponement.
When might a surgery be postponed for a patient’s benefit?
If their condition is unstable, such as a patient with left main coronary artery disease requiring a CABG before elective surgery.
What is the anesthetic plan?
A strategy to determine premedication use, anesthetic type, intraoperative management, and postoperative care.
When is general anesthesia typically used?
For surgeries above the diaphragm, such as neurosurgery, cardiac, and thyroid procedures.
What are examples of regional anesthesia techniques?
Spinal, epidural, and peripheral nerve blocks.
What factors affect intraoperative management?
Nonstandard monitors, patient positioning, contraindications to drugs, fluid management, and special techniques.
What should be considered for postoperative management?
Pain control, ICU admission, postoperative ventilation, and hemodynamic monitoring.
What is the purpose of the ASA Physical Status Classification System?
To assess and communicate a patient’s pre-anesthesia medical comorbidities.
Does the ASA classification predict perioperative risk?
No, but it can help assess risk when combined with other factors like frailty and type of surgery.
When is the final ASA classification assigned?
On the day of anesthesia care by the anesthesiologist after evaluating the patient.
What does the letter ‘E’ in ASA classification indicate?
Emergency surgery (e.g., ASA 1E).
What is ASA 1 classification?
A normal, healthy patient (e.g., non-smoker, no chronic illnesses).
What is ASA 2 classification?
A patient with mild systemic disease (e.g., controlled DM/HTN, pregnancy, mild lung disease, BMI 30-40).
What is ASA 3 classification?
A patient with severe systemic disease with functional limitations (e.g., poorly controlled DM/HTN, COPD, ESRD on dialysis).
What is ASA 4 classification?
A patient with severe systemic disease that is a constant threat to life (e.g., recent MI, ongoing ischemia, sepsis, ARDS).
What is ASA 5 classification?
A moribund patient who is not expected to survive without the operation (e.g., ruptured aneurysm, massive trauma).
What is ASA 6 classification?
A brain-dead patient whose organs are being removed for donation.
Why is pregnancy considered ASA 2?
Due to physiological changes that increase anesthetic risk compared to non-pregnant patients.
What is the definition of emergency surgery in ASA classification?
A surgery where delay increases the threat to life or body part.
How would you classify a 30-year-old female scheduled for emergency appendectomy?
ASA 1E.
What is the first monitoring device that should be connected to a patient in the OR?
Pulse oximeter.
Why is the pulse oximeter essential in the OR?
It provides continuous oxygenation and pulse rate monitoring, ensuring vigilance even without direct visual observation.
What does ASA Standard I state?
Qualified anesthesia personnel must be present throughout the administration of anesthesia.
What does ASA Standard II emphasize?
Ensuring proper monitoring of oxygenation, ventilation, circulation, and body temperature.
What equipment is used to monitor oxygenation?
Oxygen analyzer and pulse oximeter.
What methods are used to monitor ventilation?
Capnography, chest excursion observation, breath sounds auscultation.
What parameters are monitored for circulation?
Arterial blood pressure, heart rate, and ECG.
Why is body temperature monitoring important?
To prevent hypothermia or hyperthermia in critical care settings.
“How long before surgery can a patient consume a light meal (e.g., toast and clear liquids)?”
Up to 6 hours
“How long before surgery can a patient consume breast milk?”
Up to 4 hours
“How long before surgery can a patient consume clear liquids?”
Up to 2 hours
“What is the fasting recommendation for a patient within the 2-hour window before surgery?”
No solids, no liquids
“What are examples of conditions that increase the risk of aspiration, making fasting guidelines inapplicable?”
Esophageal disorders (uncontrolled reflux, hiatal hernia, Zenker diverticulum, achalasia, stricture), previous gastric surgery (gastric bypass), gastroparesis, diabetes mellitus, opioid use, GI obstruction, acute intra-abdominal processes, pregnancy, obesity, emergency procedures
“What pharmacologic agents can be used to reduce the risk of pulmonary aspiration in preoperative fasting?”
H2 blockers, PPIs, gastric protectants, gastrokinetic agents
“What is the purpose of the ASA Physical Status Classification System?”
To assess and communicate a patient’s pre-anesthesia medical comorbidities
“What is ASA 1 classification?”
A normal healthy patient (e.g., healthy, non-smoker, no or minimal alcohol use)
“What is ASA 2 classification?”
A patient with mild systemic disease (e.g., controlled DM/HTN, mild lung disease, pregnancy, obesity BMI 30-40, current smoker, social alcohol drinker)
“What is ASA 3 classification?”
A patient with severe systemic disease (e.g., poorly controlled DM/HTN, COPD, morbid obesity BMI >40, active hepatitis, pacemaker, moderate ejection fraction reduction, ESRD on dialysis, history of MI/CVA >3 months)
“What is ASA 4 classification?”
A patient with severe systemic disease that is a constant threat to life (e.g., recent MI/CVA <3 months, ongoing cardiac ischemia, severe valve dysfunction, severe ejection fraction reduction, sepsis, DIC, ARDS, ESRD not on dialysis)
“What is ASA 5 classification?”
A moribund patient who is not expected to survive without surgery (e.g., ruptured aneurysm, massive trauma, intracranial bleed with mass effect, ischemic bowel with significant cardiac pathology)
“What is ASA 6 classification?”
A declared brain-dead patient whose organs are being removed for donation
“When is the letter ‘E’ added to an ASA classification?”
For emergency surgeries where delay increases the threat to life or body part (e.g., ASA 1E)
“What is the fasting requirement for a pregnant patient before surgery?”
Pregnant patients are always considered to have a full stomach and require special precautions.
“What are the four categories of surgery urgency in perioperative cardiovascular management?”
Emergency (<2h), Urgent (≥2 to <24h), Time-Sensitive (delay up to 3 months), Elective (can be delayed for full evaluation)
“What are the two risk categories for perioperative cardiovascular events?”
Low risk (MACE <1%) and Elevated risk (MACE ≥1%)
“What are the highest-risk surgeries for MACCE?”
Suprainguinal vascular, thoracic, transplant, neurosurgery
“What are the intermediate-risk surgeries for MACCE?”
General, otolaryngology, genitourinary, orthopedic surgeries
“What are the lowest-risk surgeries for MACCE?”
Endocrine, breast, gynecology, obstetrics
“What are major cardiovascular risk factors in preoperative cardiac assessment?”
Hypertension, smoking, high cholesterol, diabetes, age >65 (women) or >55 (men), obesity, family history of premature CAD
“What are examples of risk modifiers in preoperative cardiac risk assessment?”
Severe valvular heart disease, severe pulmonary hypertension, previous CABG or coronary stenting, recent stroke, presence of CIED (ICD/pacemaker), frailty
“How does the timing of surgery affect MACCE risk?”
Emergency surgeries have the highest risk, while elective surgeries allow for risk optimization.
“What is an example of how surgical approach affects MACCE risk?”
Endovascular aortic aneurysm repair has a lower MACCE risk than open repair.
“What is the first monitoring device that should be connected upon arrival in the OR?”
Pulse oximeter
“What are the ASA standards for basic anesthetic monitoring?”
Qualified anesthesia personnel present, monitoring of oxygenation, ventilation, circulation, and body temperature
“What are the recommended methods for monitoring oxygenation during anesthesia?”
Oxygen analyzer, pulse oximeter
“What are the recommended methods for monitoring ventilation during anesthesia?”
Capnography, capnometry, chest excursion observation, breath sounds auscultation
“What are the recommended methods for monitoring circulation during anesthesia?”
ECG, arterial blood pressure, heart rate monitoring
“What is the role of qualitative clinical signs in anesthetic monitoring?”
Chest excursion, reservoir bag observation, auscultation of breath sounds, pulse palpation
“Why is the pulse oximeter the first device to be connected in the OR?”
Immediate monitoring of oxygenation and pulse rate, ensures continuous vigilance even without direct visual observation.
What is an important predictor of risk of adverse cardiovascular events after noncardiac surgery (NCS)?
Functional capacity, usually measured in metabolic equivalents (METs) of a task, with 4 METs considered the threshold for poor functional capacity.
What is a common way to assess functional capacity?
It can be assessed by asking patients if they can climb 2 flights of stairs or by using a patient-reported instrument like the Duke Activity Status Index (DASI).
What percentage of patients undergoing major NCS have coronary artery disease (CAD)?
Approximately 18%.
What is the perioperative risk associated with a history of acute coronary syndrome (ACS) compared to chronic coronary disease (CCD)?
A history of ACS confers greater perioperative risks than CCD.
What ASA classification is given to patients with a history of CAD for more than 3 months?
ASA III.
What ASA classification is given to patients with a recent history of CAD?
ASA IV.
What risk is associated with coronary stent placement in patients undergoing NCS?
Increased risk of major adverse cardiovascular events (MACE).
How should patients with CAD be managed before elective NCS?
Careful attention to optimal medical management for atherosclerotic cardiovascular disease (ASCVD) is important.
What is the benefit of preoperative revascularization in patients with ACS or left main CAD?
Preoperative revascularization can reduce the risk of MACE in patients with MI.
What should be done for patients with refractory anginal symptoms before NCS?
A multidisciplinary heart team approach to revascularization should be considered.
How does uncontrolled hypertension affect myocardial demand?
It increases myocardial demand via elevated LV end-diastolic pressure, leading to subendocardial myocardial ischemia.
What complications are increased by uncontrolled hypertension in the perioperative period?
Increased risk of cardiovascular disease (CVD), cerebrovascular events, and bleeding.
What should be considered when elevated BP is observed on the day of surgery?
It may represent a situational (‘White Coat Hypertension’) response, and the patient’s baseline ambulatory BP should guide management.
What should be administered if elevated BP is detected preoperatively?
Anxiolytics and IV antihypertensive agents may be required.
What is the most common arrhythmia in patients undergoing NCS?
Atrial fibrillation (AF).
What are the risks for patients with preexisting AF undergoing NCS?
Increased risks of all-cause mortality, heart failure (HF), and ischemic stroke within 30 days of surgery.
Do patients with AF undergoing NCS generally require changes in medical management?
If hemodynamically stable, they generally do not require changes, except for interruption of oral anticoagulation (OAC).
What complication is of concern when performing neuraxial anesthesia in patients with AF?
Increased risk of spinal or epidural hematoma.
How long should elective NCS be delayed after a stroke or transient ischemic attack (TIA)?
At least 3 months to reduce the incidence of recurrent stroke, MACE, or both.
What is the effect of delaying surgery after a cerebrovascular event?
The increased risk of MACE and stroke diminishes over time as inflammation decreases, hemorrhage risk reduces, and cerebral autoregulation is reestablished.
What is the minimum time required for aspirin to restore platelet function after interruption?
4 days.
What is the minimum time required for clopidogrel to restore platelet function after interruption?
5-7 days.
What is the minimum time required for prasugrel to restore platelet function after interruption?
7-10 days.
What is the minimum time required for ticagrelor to restore platelet function after interruption?
3-5 days.
What are the risks of perioperative major adverse cardiovascular events (MACE) when NCS is performed within the first 3 months after PCI?
The risks of MACE are highest within the first 3 months after PCI.
What is the recommended minimum time for elective NCS after PCI?
Elective NCS should not be performed within 30 days of PCI.
What therapy is associated with lower rates of death and nonfatal MI in patients undergoing NCS after PCI with stent placement?
Aspirin use.
When should dual antiplatelet therapy (DAPT) be interrupted for patients undergoing NCS?
DAPT should be interrupted at least 14 days after balloon angioplasty alone without stent placement.
What should be done if interruption of DAPT is required for NCS?
Aspirin monotherapy should be continued whenever possible.
What should be considered when delaying elective NCS in patients with high residual thrombotic risk?
Delaying surgery may allow for safer interruption of oral anticoagulation (OAC).
What are the reversal agents for vitamin K antagonists (VKA) like warfarin after a procedure?
Vitamin K and prothrombin complex concentrates.
What is a key consideration when restarting warfarin after a procedure?
It can take several days to achieve full anticoagulant effect, so it is reasonable to restart VKA as early as 12-24 hours postoperatively.
How does diabetes impact perioperative cardiovascular events and surgical site infections?
Diabetes increases the risk of cardiovascular events and surgical site infections.
What are the risks associated with stress from anesthesia and surgery in diabetic patients?
It alters the balance between hepatic glucose production and glucose utilization, affecting regulatory hormones and inflammatory cytokines.
Why is managing perioperative hyperglycemia crucial in diabetic patients?
To reduce the risks of complications such as cardiovascular events and infection.
What is the recommendation regarding GLP-1 agonists (e.g., Ozempic) before elective NCS?
Weekly formulations of GLP-1 agonists should be held >1 week before NCS, and daily formulations should be held the day before.
What is a complication of SGLT2 inhibitors that requires attention in the perioperative period?
Euglycemic diabetic ketoacidosis, which is a serious postoperative complication.
What should be done if the patient’s hemoglobin A1c is higher than 8% before elective surgery?
It may be reasonable to defer surgery if the hemoglobin A1c is higher than 8%.
What is the approach for emergent or time-sensitive procedures in diabetic patients with high A1c?
The focus should be on optimizing perioperative glucose control rather than delaying surgery to achieve a target hemoglobin A1c.
How should SGLT2 inhibitors be managed before surgery?
SGLT2 inhibitors should be discontinued 3-4 days before surgery.
What is the impact of chronic pulmonary disease on surgical patients?
Increased morbidity and mortality (M/M).
How should asthma and COPD be evaluated in the perioperative setting?
Evaluate exercise tolerance, frequency & severity of exacerbations, and focused history including intubations for exacerbations.
What is the risk of instrumentation or tracheal intubation in patients with asthma or COPD?
It may act as a noxious stimulus, causing bronchoconstriction, leading to desaturation and hypoxemia.
What causes bronchoconstriction in asthma and COPD patients during anesthesia?
Vagal afferents in the bronchi are sensitive to histamine and noxious stimuli, resulting in bronchoconstriction.
What is the effect of most inhaled anesthetics in asthma or COPD patients?
Most inhaled anesthetics act as bronchodilators.
Which inhaled anesthetic is recommended for asthmatic or COPD patients to avoid airway irritation?
Sevoflurane, as it is not an airway irritant.
What is the treatment approach for asthmatic patients with active bronchospasm presenting for emergency surgery?
Aggressive treatment with supplemental oxygen, aerosolized B2-agonists, and IV glucocorticoids.
Why are ABGs useful in asthma or COPD exacerbations?
ABGs help in evaluating the severity and adequacy of treatment.
What is the most common pulmonary disorder encountered in adult anesthetic practice?
Chronic obstructive pulmonary disease (COPD).
What is the difference between ‘blue bloaters’ and ‘pink puffers’ in COPD?
‘Blue bloaters’ typically have chronic bronchitis, while ‘pink puffers’ typically have emphysema.
How does smoking affect pulmonary function preoperatively?
Smoking increases mucus production, decreases clearance, and depletes antioxidants like glutathione and vitamin C.
What is the benefit of smoking cessation before surgery?
Cessation of smoking for as little as 24 hours can improve oxygen-carrying capacity of hemoglobin.
What is the preoperative evaluation for obstructive sleep apnea (OSA)?
Medical record review, patient/family interview, screening protocols, and review of sleep studies.
What should be considered for patients with severe OSA before surgery?
Preoperative initiation of CPAP, and in some cases, NIPPV (Non-Invasive Positive Pressure Ventilation).
What preoperative treatments should be considered for OSA?
Mandibular advancement devices, oral appliances, and preoperative weight loss.
When should a patient with a history of corrective airway surgery be assumed to remain at risk for OSA complications?
Unless a normal sleep study has been obtained and symptoms have not returned.
What tests are useful in evaluating dyspnea preoperatively?
ABGs, BNP, BUN, PFTs, CT, and other clinical evaluations.
What is the key approach to preventing acute kidney injury (AKI) in high-risk patients?
Adequate hydration and maintenance of renal blood flow.
What are the underlying causes of impaired kidney function that may impact surgery?
Glomerular dysfunction, tubular dysfunction, and urinary tract obstruction.
What is the incidence of postoperative AKI in general surgery patients?
1% to 5% of general surgery patients, and up to 30% in cardiothoracic and vascular surgeries.
What are preoperative risk factors for perioperative AKI?
Pre-existing kidney disease, hypertension, diabetes, liver disease, sepsis, trauma, and exposure to nephrotoxic agents.
What is a general recommendation for nephrology in patients with increased risk for AKI?
Avoid NSAIDs post-operatively and optimize perioperative fluid management.
What is the preferred muscle relaxant in patients with renal dysfunction?
Cis-atracurium, as it is eliminated via Hofmann elimination and not dependent on renal or hepatic metabolism.
Why should morphine and meperidine be avoided in patients with renal failure?
Their metabolites can accumulate, leading to increased risk of respiratory depression.
What is the role of the liver in drug metabolism?
The liver is responsible for metabolizing most anesthetic drugs, and hepatic dysfunction may impair this process.
What are the hemostatic changes in liver disease?
Impaired synthesis of coagulation factors, leading to prolonged PT/INR, thrombocytopenia, and endothelial dysfunction.
How does cirrhosis affect bleeding risk in surgery?
Cirrhosis can lead to excessive bleeding due to thrombocytopenia, endothelial dysfunction, and portal hypertension.
What laboratory tests are used to assess liver function preoperatively?
PT, INR, liver enzymes, albumin, bilirubin, and platelet count.
Why should elective surgery be postponed in patients with acute hepatitis?
Elective surgery should be postponed until liver function normalizes, as indicated by liver tests.
What is the risk of acute alcohol withdrawal during the perioperative period?
Acute alcohol withdrawal can be life-threatening, with a mortality rate as high as 50%.
What is the most important indicator of hepatic synthetic function?
Prothrombin time (PT) is the best indicator.
What does a persistent prolongation of PT after vitamin K administration indicate?
Severe hepatic dysfunction requiring interventions like fresh frozen plasma or platelet transfusions.
What are the perioperative risks associated with liver disease?
The degree of hepatic impairment correlates with increased perioperative risks, including difficulty awakening from anesthesia due to impaired hepatic metabolism.
