What are pre-op lab tests that are important to get for anesthesia?
Hemoglobin and hematocrit
Pregnancy test if patient is under 50
CBC
Chemistry
ECG if patient has CAD or over 50 yrs.
Urinalysis
*PT, PTT if history of bleeding disorder or if on coumadin.
Pt is in pre-op and you look at labs, hemoglobin is at 7g/dL and Hematocrit is 25%. Would it be wise to continue with elective surgery?
No, Hemoglobin and hematocrit should be at 8g/dL or higher and higher than 30% in men and 27% for weomen.
What is the lab finding that is diagnostic for polycythemia? Should you do elective surgery on someone with polycythemia?
Hematogrit greater than 57% for men and greater than 54% for women. Not sure but you should be careful because this poses with it additional risks of bleeding and thrombosis.
Patient has leukocyte value of 2,200/mm3. Is elective surgery ok? What about over 12,000?
It is advised to do further studying if WBC is less than 2,400 or higher than 12,000.
Pt is on coumadin, pt is cleared to hold for surgery. When would be a good time to start holding?
3-5 days prior to surgery or as long as it is necessary for PT to return to normal range.
Does ASA affect bleeding time?
No it hasn't been found to
Do all patients need chest XRAY prior to surgery? When is it indicated and what can it help detect?
No, if over 60 years old or if you have suspicion of heart failure or chronic lung disease. XRAY can help detect heart failure or chronic lung disease.
Which patient sneed ECG prior to surgery?
If older than 40 years old.
Pt is under General anesthetic and is experiencing extremely high fever, muscle rigidity, cardiac arrhytmias, and acidosis. What medication is patient on and what would you do to treat?
Halothane (malignant hyperthermia).
Treatment: immediate termination of anesthesia, quick cooling of body, reversal of acidosis with sodium bicarb. Dantrolene is the drug of choice for reversal.
PT presents with elevated serum creatinine phosphokinase an abnormal ECG and myopathy. What complication might the patient be suseptible to with anesthesia?
Malignant hyperthermia.
During anesthesia patient is having muscle spasms of masseter, his temperature is high, blood pressure unstable, he is acidotic, cyanotic, and there is dark blood in surgical field. What might the patient be experiencing?
Malignant hyperthermia
Intraoperatively the patients blood pressure shoots up to 190/100. What sublingual medication could you give to treat, what IV meds could be used?
Sublingual = nifedipine
IV = Sodium Nitroprusside and nitroglycerin
For severe elevations labetalol an alpha/beta blocker is sometimes used.
Pt has history of CAD what three things may you want to watch while patient is receiving anesthesia for surgery?
1. Diastolic blood pressure (to make sure its high enough to provide adequate coronary artery perfusion)
2. Sufficient hydration
3. Adequate hemoglobin and hematocrit to ensure full tissue oygenation.
Which is more advantageous for a patient with Coronary heart disease, sedation and local or general?
Sedation and local
Why might it be important to ask a patient if they have had a recent history of bronchial asthma?
Pt may need albuterol preoperatively
What is a good sedative for a patient with respiratory disease?
IV midazolam as well as IV meperidine
If general anesthesia is necessary in a patient with respiratory disease which anesthetics are favored for induction of patients with COPD?
Etomidate
Thiopental sodium
Ketamine may also be considered in patients with respiratory disease.
What is the inhalation agent of choice for patients with respiratory disease?
Halothane because its ability to prevent bronchila spasm.
An insulin-dependent pt is in pre-op ready for surgery. You ask if the patient received insulin that morning. The patient says yes, how much should the pt have injected?
1/3 to 1/2 of daily dose of intermediate acting
Pt has raging cellulites covering entire foot, he has a full-thickness ulceration sub 1st MTH. Dr. tells you to do a block. Where should you block?
You want to avoid injecting where there is infection or OM... pt may need a more proximal block or other means of anesthesizing.
Patient is morbidly obese (twice their ideal body weight), which type of anesthesia is recommended?
Obese patient provide difficult airway management, mild sedation and local or regional anesthetic infiltration or central neural blockade. Epideral however may be difficult.
Why is a sickle cell disorder pt a concern for anesthesia?
Difficulty maintaining full oxygen saturation of arterial blood, normal cardiac output, and stable blood pressure intraoperatively.
Pt has sickle cell, resident instructs you to put on tourniquet. What do you do?
Remind the resident that the pt has sickle cell disorder and if you use tourniquet you increase stasis, local aciosis, and hypoxia. The resident responds, "I know dummy, give me literature to prove it!" There really is no literature supporting this argument, however we still don't use it and you are right when it comes to boards!
What is the favored anesthesia for geriatric patients receiving elective surgery?
Regional anesthesia: Allows maintenance of consciousness and permits recongnition of acute changes in cerebral function as well as critical symptoms of angina pectoris.
Pt ate at 7 am this morning, the surgery is scheduled at 1:30 pm. Is it ok to start the procedure on schedule?
Yes, in adult pts nothing by mouth for a minimum of 6 hours, in this case it will be 6 1/2.
Child was given apple juice at 10 am and his surgery is scheduled at 12. Can you continue with the surgery as scheduled.
No, technically a child can have clear liquids up to 4 hours prior to surgery. The surgery would need to be postponed for 2 more hours.
What are the most common agents used for inhalation induction?
Oxygen
Nitrous oxide
Potent volatile agents (Halothane is volatile agent of choice because of its lack of respiratory tract irritability)
What is the most common complication with a patient being supine for anesthesia?
brachial plexus injury, especially the ulnar nerve
What specific class of sedative drugs do you want to avoid in patients with porphyria?
Barbituarates - it can precipitate an acute attack
Diazepam and lorazepam are the benzodiazepines most commonly used for relief of aniety and to invoke amnesia preoperatively. Which route of administration reaches greater blood levels...ORAL or IM?
ORAL is best, IV administration can cause vein irritation. Oral is faster induction. You give 1 to 2 hours before surgery.
Which is a beter amnesic and more potent, Diazepam (Valium) or Midazolam (Versed)
Versed! it is the best, better amnesia, more potent and can be administered IV with less SE and has quicker onset.
Which drug in small doses is often included with diazepam or midazolam to help with sedation?
Ketamine
There are 5 main opiods that are used as narcotics intraoperatively. What are they?
Morphine
Meperidine (Demerol)
Fentanyl
Sufentanil
Alfentanil
If you were doing a fairly quick outpatient procedure which narcotic would you choose?
I would choose Alfentanil. It is shortes acting of the opiates and has good induction. It also has less respiratory depression. It has often been used in combination with thiopental or nitrous oxide or with propofol.
Sufentanil is also good, it is better than fentanyl because it is more potent and causes less respiratory depression. Alfentanil is still a shorter acting.
Patient is suffering from respiratory depression due to overuse of Fentanyl. How would you reverse this?
Naloxone. The duration of action is 15 to 90 min.
Name at least 5 drugs that can be used for induction of anesthesia?
Thiopental
Methohexital
Propofol
Ketamine
Midazolam
Droperidol
Etomidate
Fentanyl
Sufentanil
Alfentanil
Name 5 inhalation agents
Nitrous Oxide
Halothane
Enflurane
Isoflurane
Sevoflurane
Nitrous oxide has a low blood gas coefficient. If you needed a fast induction would this be a good choice?
Yes. The lower the blood gas coeffient the faster the induction and emergence.
Nitrous oxide is most often used with another inhalation agent because of its rapid smooth induction and low irritability to respiratory tract.
Halothane. It is often used in pediatric patients because of the low irritability to respiratory tract.
What is the agent of choice for prevention of aspiration when a rapid-sequence induction anesthetic is used?
Succinylcholine.
Pt was given succinylcholine which is the agent of choice for prevention of aspiration, in so doing he was overdosed. What can you give the patient?
An anticholinesterase such as neostigmine.
What is a common complication of using succinylcholine as prevention of aspiration?
Muscle aches and pains. These agents are usually used with atropine to counteract the muscarinic actions that consist of an increase in salivation and bronchial secretions and bradycardia.
Out of all the volatile agents which has the lowest blood solubility and pt responds to the quickest?
Isoflurane
As you roll the pt back to post-op they complain they are nauseus and ready to vomit. Name 2 possible medications you can give them
Zofran
Reg-lan
Droperidol
As you roll the patient into the operating room they ask, what is the mortality rate of general anesthesia?
You respond, "oh about 0.5%" but if you have voexisting CV disease it can be up to 5%. The patient is conforted because she doesn't have any CV disease.
What is one of the biggest SE of general anesthetics with diabetics?
Silent myocardial infarctions
Atelectasis in general not specifically for diabetics
What is a rare complication of halothane?
liver damage or halothane hepatitis
What is the prefered position for administration of epidural anesthesia
lateral prone position
What is the advantage of epidural anesthesia over spinal?
Lower potential for postanesthetic headache. Also you can do a continuous indwelling catheter.
What is the most commonly used local anesthetic used for spinal anesthesia?
Bupivicaine
Which is more advantageous for ambulatory surgery, spinal block or epidural?
Spinal block is more efficatoius, it has shorter induction time and lower incidence of nausea and vomiting.
You are on anesthesia rotation, the anesthesiologists asks you to do a bier block on a patient due to their contraindications for general and spinal/epidural block. HOw would you do it?
Touriquet is placed just below the knee and IV is placed in which the lidocaine is injected to LE. Local diffuses out of vein into surrounding tissues.
T/F Epinephrine shortens the onset and prolongs the effect of the local anesthetic?
T
WHat are the 3 main systemic complications of local anesthetics?
Tinnitus, convulsions, and anxiety
What is the component in local anesthetics that people with allergy are allergic to?
methylparaben (preservative in local anesthetics)
How long does the vasocontriction effect of epinephrine last?
20 min to 1 hour.
Where is the sciatic nerve located in relation to the ischial tuberosity?
