Question | Answer |
Preanesthesia Standards | I- perform a thorough/complete assessment
II- Obtain informed consent for the planned anesthetic intervention from the patient or legal guardian
III- Formulate a patient-specific plan of care |
What is the most significant predictor of postop morbidity and mortalitiy? | The patient's preoperative condition |
Goals of the preop exam | *gather information and formulate patient specific plan *minimize perioperative morbidity/mortality by assessing pt health issues *evaluate the patient's health and determine what preop tests or consultations needed *establish a trusting relationship |
What general information should you be able to obtain from the medical record? | -age -height -weight -surgical consent -admission VS -progress notes and consultation notes -medical treatments and dosages |
Important Components of the PreOP interview | - History (previous anesthetics, allergies)
-Current medical therapy
-Physical exam (CV, pulmonary, and airway)
-Interpretation of lab data |
Previous Adverse Responses Related to Anesthesia | -Allergic
-Sleep Apnea
-Prolonged skeletal muscle paralysis
-N/V
-Myalagia
-Hemorrhage
-Postdural Puncture headache
-Adverse response in relatives |
Family Anesthetic Experiences | -most patients are NOT at increased risk even if a family member died under anesthesia
-certain inherited conditions are only expressed when exposed to certain anesthetics |
Malignant Hyperthermia | -rare, life-threatening condition of muscle metabolism
-genetic: family members of patient's with MH should be tx as if they also have it
-sustained muscle contraction causes massive energy expenditure and hypermetabolic state |
Clinical Features of MH | -muscle rigidity
-masseter spasm
-rising etC02 and PaC02
-decrease in Sp02 and Pa02
-Tachypnea
-Tachycardia (**1st symptom)
-fever (late sign)
-metabolic acidosis |
The majority of meds are continued preoperatively (T or F) | TRUE |
Drugs that cause tolerance to anesthetic drugs | -ETOH abuse -Benzos |
Drugs that exaggerate response to sympathomimetics | MAOI and TCA |
Latex Allergies | -range of reactions possible
-Irritant Dermatitis (not ax to latex, usually due to sweating or detergents)
-Allergic Contact Dermatitis (reaction to latex or chem additives)
-Hypersensitivity Immune System Reaction |
Risk factors for Latex Sensitivity | -chronic exposure to latex products -spina bifidia -repeated surgical procedures (9+) -known intolerance to latex products (i.e.condoms) -allergy to fruit and tropical fruit (kiwi, peach, advocate) -Intraop anaphylaxis of unknown cause -health care worker |
Tobacco Use | -smoking rates down to 19%
-over 4000 compounds in cigs
-Inquire amount smoked and years smoked |
Nicotine | -sense of relaxation, well-being, and heightened concentration
-long term causes release of catecholamines (vasoconstriction)
-Incr. Coagulation (sticky/adherent plts, increased viscosity d/t fibrinogen & RBCs stack to form conglomerations |
Carbon Monoxide | -high affinity for Hgb
-bond btw Hgb CO is 250x stronger than O2
-Inhaled CO displaces 02 causing hypoxia |
Smoking Effects | -small airways in lung narrow and prone to collapse
-increase in mucus, decreased ability to clear mucus
-excess mucus and inflammation lead to progressive and permanent lunch damage
-increased bronchial reactivity/sensitivity |
Tobacco Sessation Benefits for Surgery | 12-24 hours effects of CO decrease and much of the nicotine is cleared from blood, 48hrs needed for changes in airways reactivity/sensitivity -improvement of secretion and small airways takes 4-8 weeks -after 10 weeks anesthesia risks reduced to nonsmoker |
Opiod Abuse effect on anesthetic requirement | Acute: decrease
Chronic: increased |
Barbituate Abuse effect on anesthetic requirement | Acute: decreased
Chronic: increased |
Marijuana use and anesthetic requirment | Acute: decreased
Chronic: no effect |
Amphetamines effect on anesthetic requirement | Acute: increased need
Chronic: decreased need |
Cocaina effect on anesthetic requirement | Acute: increase
Chronic: no change |
Phencylidine (PCP) | Acute: decreased
Chronic: unknown |
Thyromental Distance | -distance from thryoid notch to bony point of chin with head extended
-7cm (3 fingers) or LESS is assoc w difficult intubation |
Standard Lab Testing | Age 0-12: none
Age 13-49: Hct for females (valid for 1 month), HCG if appropriate
Age 50+: Hct, EKG, lytes (labs valid 1 month, EKG 6 months) |
Preop Testing for know CV disease | -EKG
-electrolytes
-CXR
-cardiology consult |
Preop Testing for known Pulmonary disease | -ABG
-CXR (good for 6 months)
-PFT (significant symptoms)
-medicine or pulm consult |
Preop Tesing for Renal | -BUN/Cr
-glucose
-lytes
-PT/PTT
-platlets |
Preop Testing for Liver Disease | -BUN/Cr -Glucose
-electrolytes
-LFTs
-PT/PTT
-platlets |
Labs for patient on anticoagulant therapy | -coags
-fibrinogen
-platlets
-consider hematology consult |
Chronic Meds that require preop labs | -Diuretics (lytes, BUN/Cr)
-Steroids (lytes, glucose)
-Digitalis (lytes, Bun.Cr, EKG)
-Anti-convulsant: drug levels |
When do you order T&S? | -major blood loss (>500ml)
-Intermediate blood loss (50-500ml) if elderly (>70), significant medical probe, anemia, or required previous transfusion
-if patient had transfusion or was pregnant w/in 6 mos |
Repeat EKG guidelines for diabetics | -Within 1 month if previous EKG abnormal
-Within 3 months if previous EKG normal and no symptoms |
Repeat EKG guidelines for Non-diabetics | -Within 6 months if previous EKG abnormal and no symptoms
-Within 1 year if previous EKG normal and no symptoms |
Pregnancy Testing | Women of reproductive age SHOULD have blood pregnancy test within 38-72 hours of surgery, same day urine test is alternative but less sensitive
-Why? anestetics can be teratogenic, risk of abortion, elective surgery should wait until after 1st trimester |
Complications of prolonged fasting | -Dehydration -Hypoglycemia - Increased Irritability -Thirst -Hunger -Headache |
Pulmonary Aspiration | #1 cause of anesthesia death, aspiration pneumonitis occurs in1-7:10,000 cases |
Patients at risk for Aspiration | -GI obstruction, GERD, DM/gastroparesis, pregnancy, abdominal distension (obese, ascites), recent solid food, recent opioid, depressed LOC, airway trauma, nasopharyngeal or upper GI bleed |
Critical Values for Aspiration | pH < 2.5 and volume >25ml |
Aspiration of Acidic Content | -immediate aleveolar-capillary breakdown
-interstitial edema, intraalveolar hemorrhage, atelectasis, increased airway resistance and hypoxia |
Aspiration of Nonacidic Content | destroys surfactant, causes alveolar collapse, atelectasis and hypoxia
-aspiration of food causes physical obstruction and later inflammatory response
-results in alternating areas of atelectasis and hyper expansion, hypoxia, and hypercapnea |
Symptoms of Aspiration | -can be silent
-tachypnea
-rales
-cough
-cyanosis
-wheezing
-fever
(if patient aspirates and within 2 hours no symptoms- full recovery)
(75% of pts with symptoms require 02 or ventilation w/in 2 hrs) |
Prevention of Aspiration | -recognize risk
-fasting guidelines
-preanesthetic treatment to increase pH and decrease volume
-rapid sequence
-awake intubations |
Fasting Guidelines | Clears: 2 hrs Breast Milk: 4 hrs Infant Formula: 6 hrs Light Meal: 6 hrs Heavy Meal: 8 hrs |
General Anesthesia | A reversible, drug induced coma during which the patient will no perceive or respond to pain. Should include: unconsciousness, amnesia, akinesia, analgesia, and reversibility |
MAC anesthesia | -administration of sedative and anesthetic drugs producing effects ranging from awake to light sleep -standard of care is the same for MAC as general -Airway management skill is required of the provider giving MAC |
Reasons to AVOID regional anesthesia | -low platelets -antiplatlet therapy -spinal disease -spinal fracture -sepsis -AS |
Reasons for Premedications | -Patient Comfort -Decrease gastric pH/volume -decrease airway secretions -decrease risk of PONV -prevent ABX |
Factors to Consider when Premedicating | -ASA status -Age -Weight -Level of pain/anxiety -Allergies -Hx of drug abuse/use -previous PONV -planned surgical procedure -inpatient or outpatient |
PreOp Meds: Benzos | -most commonly administered drugs for sedation and anxiety
-Versed and Ativan produce anterograde amnesia
-can produce excessive sedation in some pts |
PreOp Meds: Opiods | -use for preop pain control
-use if patient requires invasive procedures before surgery
-use before insertion of spinal/epidural (non-OB) |
PreOp Meds: Antihistamine | -prophylaxis against allergic reaction
-sedative and antiemetic properties |
PreOp Meds: Anticholinergics | -used for antisialagogue effect
-sedative and amnestic properties (scopolamine)
-prevent reflex bradycardia |
Why might we give preop steroids? | Stress dose given if patient was on steroids prior to surgery |
According to SCIP the most common complications after surgery are.. | -Surgical site infection and postoperative sepsis, CV complications, Respiratory complications, throboembolic complications |