Intra-Operative Discussion Topics for General OR Rotation

 

1.                  Pharmacology:

a.                   General concepts:

i.                     Pharmacokinetics – protein binding, partition coefficients, pKa, ionization, tissue uptake.

ii.                   Elimination, biotransformation, termination of action.

b.                  Anesthetic gases:

i.                     Concept of minimal alveolar concentration (MAC).

ii.                   Physical properties – vapor pressure, MAC%, partition coefficients

iii.                  Mechanism of action.

iv.                 Factors affecting inspiratory (FI), alveolar (FA), and arterial (Fa) concentrtions.

v.                   Effects on CNS, circulation, respiratory, neuromuscular function, renal function, hepatic function, hematologic and immune systems.

vi.                 Biotransformation and toxicity.

vii.                OR pollution and personnel harards – including mutagenicity, teratogenicity, carcinogenicity.

c.                   Intravenous anesthetics: opioid and non-opioid induction and anesthetic agents

i.                     Mechanism of action.

ii.                   Pharmacokinetics and pharmacodynamics.

iii.                  Metabolism and excretion.

iv.                 Effects on circulation.

v.                   Effects of respiration.

vi.                 Effect on other organs.

d.                  Muscle relaxants: depolarizing and non-depolarizing

i.                     Mechanism of action.

ii.                   Non-relaxant side effects.

iii.                  Abnormal responses.

iv.                 Biotransformation and excretion.

v.                   Prolongation and termination of actions.

vi.                 Reversal agents – indications, mechanism of action, and side effects.

vii.                Drug interactions – antibiotics, H2 blockers, magnesium … etc.

e.                   Autonomic drugs:

i.                     Sympathetic:

1)                  Transmitters and receptor types.

2)                  Target organ and metabolic effects.

3)                  Agonists – peripheral and central actions.

4)                  Antagonists – alpha and beta blockers, antihypertensives, ganglionic blockers, peripheral vasodilators.

5)                  Tocolytic uses.

ii.          Parasympathetic:

1)                  Transmitters and receptor types

2)                  Muscarinic effects

3)                  Nicotinic effects

4)                  Agonists – cholinergic and anticholinesterases

5)                  Antagonists

f.                    Drug interactions:

i.                     Protein binding.

ii.                   PH effect.

iii.                  Enzyme induction and inhibition.

iv.                 Effects of hepatic blood flow

 

2.                  Physics:

a.                   Mechanics – medical gas cylinders (gases, types, pressures, color), diameter and pin index safety systems, gas cylinder pressure volume relationship, gas inlets and pressure regulators.

b.                  Flow velocity – flowmeters (rotameter, electromagnetic, ultrasonic), pneumotachogram.

c.                   Vaporizers – types (copper kettle, agent-specific, Tec-6 … etc).  Vapor pressure and calculation of anesthetic concentrations.

d.                  Uptake and distribution of inhalation agents:

i.                     Uptake and elimination curves – effect of ventilation, circulation, and anesthetic systems.

ii.                   Concentration effect.

iii.                  Second gas effect.

iv.                 Nitrous oxide – effects in closed spaces and diffusion hypoxemia.

e.                   Breathing system:

i.                     Principles – resistance, turbulent flow, mechanical deadspace, rebreathing, dilution, leaks, gas mixtures, humidity, heat exchange.

ii.                   Components – connectors, adaptors, breathing tubes, resevoir bag, unidirectional valves, relief valve

iii.                  Characteristics –

1)                  Circle systems – closed and semi-closed.

2)                  Non-circle systems - insufflations, open, semi-closed.

3)                  Non-rebreathing valves.

4)                  CO2 absorption – principles, canisters, efficiency (granules size and channeling).

iv.                 Oxygen supply system and oxygen sensor.

v.                   Waste gas scavenger systems

vi.                 Fail safe and other safety features.

f.                    Monitoring including measurement methods, indications, interpretation for various clinical conditions, and limitations of:

i.                     EKG – normal parameters including rate, rhythm, axis, and intervals.  Recognize and interpret various types of heart blocks, bundle branch block, ventricular hypertrophy, arrhythmia (SVT, VT/VF, AF/Aflutter, PVC/PAC, WPW, aberration), ischemia, injury, and infarction patterns.

ii.                   Arterial blood pressure – especially with respect to the differences in sites of measurement, damping, overshoot, resonance in intra-arterial monitoring.

iii.                  Central venous pressure

iv.                 Pulmonary artery pressure

v.                   Left ventricular end-diastolic pressure

vi.                 Cardiac output (Fick, dye dilution, thermodilution, Doppler)

vii.                Pulse oximetry – Beer-Lambert law, absorption wavelengths.

viii.              Capnography – phases of inspiration and expiration.

ix.                 Anesthetic gas analysis

x.                   Neuromuscular monitoring – different stimulation patterns

xi.                 Blood gases – electrode design, calibration, temperature corrections.

 

3.                  General anesthesia:

a.                   Premedications – interactions with chronic drug therapy and anesthetic agents, adverse effects, impacts on different disease states (thyroid dysfunction, chronic or acute drug abuse, glaucoma, uremia, increased CSF pressure, chronic steroid usage, obesity, depression, COPD), alteration of gastric fluid volume, pH, and sphincter tone.

b.                  Depth of anesthesia - stages and signs, monitoring.

c.                   Awareness under anesthesia – causes, prevention, medical and legal management of awareness.

d.                  Bronchospasm and laryngospasm – etiology, treatment, and prevention.

e.                   Fluid management – body compartments, assessment of deficits, replacement strategies, crystalloid versus colloid.

f.                    Transfusion – indications and contraindications of various blood products (whole blood, PRBC, FFP, Cryo, platelets), typing, screening, cross matching, complications including infection risks, citrate toxicity, hypothermia, and transfusion reactions (see also transfusion reactions under Idiosyncratic reactions).

g.                   Alternatives to transfusion of blood bank products – indications, contraindications, techniques, and disadvantages of autologous transfusions, cell saver/autotransfusion, normovolemic hemodilution,  donor-directed transfusions, and deliberate hypotension.

h.                   Hypoxemia – etiologies, diagnosis, systemic effects, and treatment.

i.                     Hypocarbia – hypercarbia – etiologies, diagnosis, systemic effects, and treatment.

j.                    Emergence delirum – differential diagnosis, etiologies, prevention, and treatments

 

4.                  Regional anesthesia (neuraxial blocks)

a.                   Spinal – indications, contraindications, anatomy, sites of actions, techniques, differential blockade, baricity, complications, and management of complications.

b.                  Epidural – indications, contraindications, anatomy, sites of actions, techniques, test dose,  differential blockade, complications, and management of complications.

c.                   Local anesthetics – factors influencing onset, duration, and termination of action.  Systemic toxicity and treatment of toxicity.

 

5.                  Patients with cardiac diseases:

a.         Determinants of myocardial oxygen supply and demand, and optimization of supply-demand ratio.

b.         Preoperative assessments and assessment of perioperative risk.

c.                   Anesthetic considerations and management of patients with coronary artery disease including monitoring and perioperative use of beta-blockers.

d.                  Anesthetic considerations and management of patients with valvular disease including monitoring and the use of prophylactic antibiotics.

e.                   Anesthetic considerations and management of patients with heart failure including monitoring and optimization strategies.

f.                    Anesthetic considerations and management of patients with arrhythmia or dysrrhythmia including monitoring and the issues related to patients with pace makers or AICD.

g.                   Anesthetic considerations and management of patients with hypertension including the etiology, pathophysiology, and treatment options.

 

6.                  Patients with pulmonary diseases:

a.                   Obstructive disease – types and etiologies (upper airway, tracheobronchial, parenchymal).

b.                  Restrictive disease – types and etiologies (neurologic, musculoskeletal, parenchymal, pleural and mediastinal, pain, abdominal compartment).

c.                   Preoperative assessment and assessment of perioperative risk

d.                  Anesthetic management –

i.                     Effects of anesthesia and surgery on pulmonary function.

ii.                   Preoperative preparation – respiratory therapy, drug therapy (antibiotics, bronchodilators, steroids, mucolytics),  smoking cessation, premedications.

iii.                  Intraoperative management – monitoring, choice of anesthesia, induction and maintenance agents.

iv.                 Postoperative care – pain management, respiratory therapy, ventilator support, extubation criteria.

 

7.                  Patients with renal diseases:

a.                   Pathophysiology of renal disease and uremia.

b.                  Anesthetic considerations and management of patients with renal insufficiency or failure.

c.                   Diuretics – types, mechanism of action, adverse effects, effect on eletrolyte and acid base balance.

d.                  Oliguria and acute renal failure – differential diagnosis and management.

 

8.                  Patients with endocrine diseases:

a.                   Diabetes mellitus – pathophysiology, impact on organ function, perioperative glucose control and anesthetic management.  Emergency anesthesia for patients with diabetic ketoacidosis and hyperosmolar coma.

b.                  Thyroid disease –

i.                     Hyperthyroidism - Metabolic and circulatory effects, anesthetic considerations and management including thyroid storm.

ii.                   Hypothyroidism – Metabolic and circulatory effects, replacement therapy, anesthetic considerations and management including myxedema coma.

c.                   Parathyroid disease –

i.                     Hyperparathyroidism – physiological effects and anesthetic management.

ii.                   Hypoparathyroidism – physiological effects and anesthetic management including postoperative issues.

d.         Adrenal disease -

i.                     Cushing’s syndrome – physiological effects and anesthetic management.

ii.                   Primary aldosteronism – physiological effects and anesthetic management.

iii.                  Addison’s disease – physiological effects and anesthetic management.

iv.                 Pheochromocytoma – metabolic and circulatory effects, diagnosis, and anesthetic considerations and management.

e.                   Pituitary disease –

i.                     Hyperpituitarism – physiological effects and anesthetic management including airway issues in patients with acromegaly.

ii.                   Hypopituitarism – physiological effects and anesthetic management including issues in patients with diabetes insipidus.

iii.                  Syndrome of inappropriate ADH – physiological effects and anesthetic management.

f.          Carcinoid syndrome – physiological effects and anesthetic management.

 

9.                  Patients with hematologic diseases:

a.                   Anemia – differential diagnosis, compensatory mechanisms, polycythemias, primary vs secondary.

b.                  Coagulopathy – differential diagnosis including congenital, acquired, and pharmacologic.  Treatment options.

c.                   Hemoglobinopathies – pathophysiology and anesthetic management of patients with sickle cell disease.

 

10.              Geriatric patients:

a.                   Physiologic changes and co-existing diseases, and their impact on anesthetic management.

b.                  Common post-operative complications – respiratory insufficiency, myocardial dysfunction, renal insufficiency, hypothermia, sedation, and delirium.

 

11.              Morbidly obese patients:

a.                   Definition of morbid obesity.  Pulmonary (including Pickwickian syndrome), cardiovascular, gastrointestinal, and metabolic changes that effect anesthetic management. 

b.                  Induction, intubation, intra-operative, and post-operative management issues.

 

12.              Obstetric patients for non-obstetric surgery:

a.                   General physiologic changes of pregnancy and their impact on anesthesia.

b.                  Basic objectives (maternal safety, avoidance of teratogenic agents, avoidance of intrauterine fetal distress, prevention of preterm labor) in anesthetic management.

c.                   Appropriate monitoring (maternal and fetal).

 

 

 

13.              Trauma and burn patients:

a.                   Trauma patient - assessment including airway, cervical spine, vital signs, volume status, and other co-existing injuries (cardiovascular, thoracic, visceral).  Anesthetic management.

b.                  Burn patient – types of burn, classification, physiological changes (respiratory, cardiovascular, metabolic), fluid replacement strategy (Parkland and Brooke formulas), airway and pain management, and anesthetic considerations including the effect of proliferation of extra-junctional receptors, carbon monoxide poisoning.

 

14.              Electroconvulsive therapy:

a.         Indications, contraindications, physiologic effects, psychiatric drug interactions, and anesthetic management.

 

15.              Laparoscopic surgery:

a.                   Anesthetic considerations – positioning, respiratory and hemodynamic effects of pneumoperitonium, and post-operative nausea and vomiting.

 

16.              Ophthalmologic surgery:

a.                   Intra-ocular pressures (IOP) – normal range and factors (including anesthetic agents) that effect IOP.

b.                  Oculocardiac reflex – pathophysiology, prevention, and management.

c.                   Regional anesthesia – indications, complications, and management.

d.                  General anesthesia – indications, complications (including the effects of succinylcholine, nitrous oxide, emergence agitation/coughing/hypertension/pain), anesthetic management, and timing of general anesthesia in patients with recent eye surgeries treated with air/sulfur hexafluroride.

 

17.              Orthopedic surgery:

a.                   Anesthetic considerations of patients with osteoarthritis.

b.                  Intra-operative considerations – adverse effects of methylmethacrylate, tourniquet induced hemodynamic changes, prone positioning (airway edema, decrease preload and lung compliance, post-operative blindness), isovolemic hemodilution, deliberate hypotension, wake-up test, and somatosensory-evoked potential monitoring.

 

18.              Urologic surgery:

a.                   Respiratory and cardiac effects of lithotomy position.

b.                  General versus regional anesthesia for urologic surgery.

c.                   Transurethral resection of the prostate (TURP) – complications, TURP syndrome (manifestations, diagnosis, management).

d.                  Anesthetic considerations and management of patients with autonomic hyperreflexia.

e.                   Anesthetic considerations and management of patients for extracorporeal shock wave lithotripsy.

f.                    Anesthetic considerations and management of patients for radical cystectomy.

g.                   Anesthetic considerations and management of patients for renal transplantation.

h.                   Anesthetic considerations and management of patients for pheochromocytoma resection.

 

19.              Transplant surgery:

a.       Kidney transplant – Anesthetic considerations and management.

b.      Pancreatic transplant – Anesthetic considerations and management.

c.       Organ donor – definition of brain death.  Anesthetic considerations and management.

 

20.              Procedures outside the operating rooms: general considerations.

a.       Cath lab

b.      MRI/MRT – issues with magnetic field, monitoring, closed circuit television

c.       CT Scanner – general versus conscious sedation.

d.      REI – conscious sedation versus regional, drugs to avoid

e.       GI Endoscopy

 

21.              Nausea and vomiting:

a.                   Physiology, etiology, gastroesophegeal sphincter, gastric emptying time.

b.                  Treatment choices – H2 blockers (i.e. ranitidine), pro-kinetics agents (metoclopramide), butyrophenones (droperidol), HT3 blockers (i.e. dolasetron), anti-cholinergics (i.e. scopolamine), steroids (i.e. dexamethasone), benzodiazepine (i.e. lorazepam), oxygen, acupressure (i.e. Sea-Band).

 

22.              Aspiration:

a.         Pneumonia and pneumonitis – etiology, diagnosis, treatment, and prevention.

 

23.              Temperature regulation:

a.                   Mechanisms of temperature control - conduction, convection, evaporation, and radiation.

b.                  Temperature sensing – central and peripheral, concept of set point.

c.                   Mechanisms of heat loss – re-distribution of heat from core to peripheral.

d.                  Heat production and conservation - shivering

e.                   Body temperature measurements – sites and gradients.

f.                    Complications of hypothermia – infection, coagulopathy, increased metabolic demands, arrhythmia, incomplete muscle reversal … etc.

 

24.              Electrical safety and fire hazards:

a.                   Electrical safety – prevention, grounding, ground leakage circuit breaker, isolation transformers, line isolation monitor.  Micro and macro current hazards.

b.                  Fire hazards – source of ignition, static discharge, misuse of oxygen, and management of fire.

c.                   Alarms – know the meaning of various alarms systems of the operating room, electrical system, anesthesia machine, ventilators, and oxygen sensor.

 

 

25.              Pharmacogenetics:

a.                   Malignant hyperthermia – pathophysiology, diagnosis, and treatment.

b.                  Pseudocholinesterase deficiency – incidence, pathophysiology, diagnosis, and treatment.

 

26.              Idiosyncratic reactions:

a.                   Anaphylactoid and anaphylactic – pathophysiology, manifestations, diagnosis, and management.

b.                  Latex allergy – incidence, diagnosis, prevention, and management.

c.                   Transfusion reactions – types, diagnosis, and management.