FDMA FLAP - The first dorsal metacarpal artery (FDMA) flap is used mainly for...
Preanesthetic evaluation
2. AIM
PURPOSE OF MEETING OF PATIENT AND ANAESTHESIST
IMPORTANT FUNCTION OF PREOPERATIVE EVALUATION ARE
General Health Assessment
What Are the Different Methods of Surgery
According to ASA
Laboratory work up
The normal AND ABNORMAL blood picture
INR ,PT, PTT and ISI
Electrolyte and creatinine
CVS assesment
Exercise tolerance
Chest radiographs
Elecro cardiogram
Pulmonary function test
Diabetes mellitus
Steroids
Management of patient of anticoagulant
Conclusion
bibliography
3. THE ULTIMATE GOAL OF PREOPERATIVE MEDICAL
ASSESMENT OF PATIENTS ARE TO REDUCE THE MORBIDITY OF
SURGERY, TO INCREASE QUALITY BUT DECREASE COST OF
POST OPERATIVE CARE, AND TO RETURN THE PATIENT TO
DESIRABLE FUNCTIONING AS QUICKLY AS POSSIBLE
4. AS A CONSULTANT, THE QUESTION ASKED IS: “FOR THIS
PATIENT, ARE THE MEDICAL CONDITIONS AS GOOD AS THEY
CAN BE?”
5. PURPOSE
1. Documentationof the condition(s)for which surgery is needed.
2. Assessment of the patient’soverall healthstatus.
3. Uncoveringof hidden conditionsthat could cause problems both during and after surgery.
4. Perioperative riskdetermination.
5. Optimizationof the patient’smedical conditionin order to reduce the patient’ssurgical and
anestheticperioperativemorbidityor mortality.
6. 6. Development of an appropriateperioperativecare Plan.
7. Educationof the patient about surgery, anesthesia, intraoperativecare and postoperative
pain treatments in the hope of reducing anxiety andfacilitating
recovery.
8. Reductionof costs, shortening ofhospital stay, reduction of cancellationsand increase of
patient satisfaction.
7. 1. OPTIMIZING PATIENT HEALTH BEFORE SURGERY
2. MOST APPROPRIATE PERIOPERATIVE MANAGEMENT
8. The history- include a past and current medical history,
a surgical history,
a family history,
a social history (use of tobacco, alcohol and illegaldrugs),
a historyof allergies
current and recent drug therapy,
unusual reactionsor responses to drugs and any problems or complicationsassociatedwith previous anesthetics.
Systemic history-
• look for undiagnosed chronic disease
• Inadequately controlled chronic disease
10. 1..Class A- minimally invasive-
° less potentialto disrupt normal physiology.
° Rarelyassociatedwith morbidityassociatedwith anesthesia
° Rarelyrequire blood administration,invasive monitoring,or postoperative management in intensive care serting
2.. Class B-moderately invasive
° modest potentialto disruptnormal physiology
° may require blood administration
° Invasive monitoringor monitoringin intensive care
11. 3.. Class 3 highly invasive –
Significant disrutption of normal physiology
Almost always require blood administration
Invasive monitoring or post operative management in critical care setting
15. Complete blood count:-
Red blood cells, which carry oxygen
White blood cells, which fight infection
Hemoglobin, the oxygen-carrying protein in red blood cells
Hematocrit, the proportion of red blood cells to the fluid
component, or plasma, in your blood
Platelets, which help with blood clotting
19. A prothrombin time (PT) is a test used to help detect and diagnose a bleeding
disorder or excessive clotting disorder;
The international normalized ratio (INR) is calculated from a PT result and is
used to monitor how well the blood-thinning medication (anticoagulant)
warfarin is working to prevent blood clots.
The partial prothrombin time (PTT) test evaluates those protein factors that are
part of the intrinsic and common pathways
20. For calculating the international normalized ratio, a patient's prothrombin time is
divided by the mean normal prothrombin time. This ratio is raised to a power
called the international sensitivity index
The reference range for prothrombin time is 9.5-13.5 seconds.
The reference range for international normalized ratio (INR) is less than 1.3
However, the normal range is highly variable and dependent on the laboratory
performing the test
21. The prothrombin time is a measure of the integrity of the extrinsic and
final common pathways of the coagulation cascade. This consists of
tissue factor and factors VII, II (prothrombin), V, X, and fibrinogen.
The test is performed by adding calcium and thromboplastin, an
activator of the extrinsic pathway, to the blood sample then measuring
the time (in seconds) required for fibrin clot formation.
23. ELECTROLYTES ARE MINERALS IN YOUR BLOOD AND OTHER BODY FLUIDS
THAT CARRY AN ELECTRIC CHARGE
COMMON ELECTROLYTES INCLUDE:
Chloride: 95-105 mmol/L
Creatinine: 0.8-1.3 mg/dL
Glucose: 65-110 mg/dL
Inorganic phosphorous: 1-1.5 mmol/L
Ionized calcium: 1.03-1.23 mmol/L
Magnesium: 1.5-2 mEq/L
Potassium: 3.5-5 mmol/L
Sodium: 135-145 mmol/L
Total calcium: 2-2.6 mmol/L
Urea: 1.2-3 mmol/L
Uric acid: 0.18-0.48 mmol/L
25. American college of cardiology and american heart association published guidelines for CVS
evaluation for non cardiac surgeries
26. It is usually evaluatedby the estimatedenergy requirement for various activitiesand graded in
metabolicequivalents(MET) on a scale definedby the Duke Activity Status Index
One MET represents the oxygen consumptionof a resting adult (3.5 ml/kg/min).
30. Electrocardiography (ECG or EKG*) is the process of recording the electrical activity of the heart
over a period of time using electrodes placed on the skin
32. Pulmonary function tests(PFTs) are a group of tests that measure how well your lungs work. Thisincludes how
well you’re able to breathe and how effective your lungs are able to bring oxygen to the rest of your body
35. Procedure-related risk factors: primarily based on how close the
surgery is to the diaphragm (i.e. upper abdominal and thoracic
surgery are the highest risk procedures).
Length of surgery (> 3 hours) and general anesthesia (vs. epidural
or spinal).
Emergency surgery.
Underlying chronic pulmonary disease or symptoms of respiratory
infection.
Smoking.
Age >60 years.
Obesity.
Presence of obstructive sleep apnea.
Poor exercise tolerance or poor general health status.
38. it is important to remember that patient is more likely to be harmed by neglect of the
long term complications of diabetes than from the short term control of blood
glucose levels
diabetic patient who needs elective surgery should be carefully assessed
preoperatively for symptoms and signs of peripheral vascular, cerebrovascular and
coronary disease
39. Adequate control of blood glucose concentration (< 180 mg/dL) must
be established preoperatively and maintained until oral feeding is
resumed after operation.
Oral hypoglycemic agents are withheld the day of surgery for an agent
with a short half-life and up to 48 h preoperatively for a long acting
agent such as chlorpropamide.
A combination of glucose and insulin is the most satisfactory method
of overcoming the deleterious metabolic consequences of starvation
and surgical stress in the diabetic patient. Generally, there is no need
for insulin infusion in diabetics who are diet-controlled regardless of
type of surgery, or in diabetics who are on oral agents only and are
undergoing minor surgeries.
40. Patients on steroids who present for surgery may be at increased risk of
complications because of
The adrenal suppression
The disease or condition which required them to take steroids
Long-term and other side-effects of steroid therapy
patient.info/doctor/precautions-for-patients-on-steroids-undergoing-surgery
41. Establish how much steroid has been taken
and for how long.
10 mg/day or more of prednisolone (or
equivalent) is generally taken as the
threshold dose for 'steroid cover'.
42. The risk of adrenal suppression
In normal healthy patients there is a prompt secretion of cortisol with the
onset of surgery and secretion remains elevated for several days after
surgery. Glucocorticoids are not stored and must be synthesised when
required - for example, during and after surgery. This response depends on
the hypothalamopituitary axis which may be suppressed or unresponsive
to stress when steroids have been taken. Failure of cortisol secretion may
result in the circulatory collapse and hypotension characteristic of an
hypoadrenal or 'Addisonian' crisis.
44. Preoperative assessment
This should focus on the history of steroid usage, routine examination
(including blood pressure) and basic investigations including FBC, U&Es,
blood glucose and LFTs.
Investigation for adrenal suppression is rarely done. It is possible to assess
this with:
1. Serum and urinary cortisol.
2. Short synacthen test (SST) - more popular but interpret with care. [5]
3. Insulin tolerance test.
4. Corticotropin-releasing hormone (CRH) measurement.
45. Patients on corticosteroids at a dose of 10 mg or more of prednisolone
Patients who have received corticosteroids 10 mg daily within the three months
preceding surgery.
Patients on high-dose inhaled corticosteroids
Minor surgery - 25 mg hydrocortisone at induction
Moderate surgery
Major surgery
47. Major concern is when to perform surgery. Ie
without risk of hemorrhage or
thromboembolism
48. 1. Most patients can undergo dental extractions, arthrocentesis,
biopsies, ophthalmic operations and diagnostic endoscopy without
alteration of their regimen.
For other invasive and surgical procedures, oral anticoagulation
needs to be withheld and the decision whether to pursue an
aggressive strategy of perioperative administration of intravenous
(IV) heparin or subcutaneous (SC) low-molecular-weight heparin
(LMWH) should be individualized
49. Management recommendations:
1. If INR pre-op is 2-3, stop oral anticoagulant 4 days prior to
surgery (or longer if INR > 3.0).
2. Measure INR one day prior to surgery: if it is ≥ 1.7, give 1 mg
vitamin K SC.
3. If on the day of surgery the INR is 1.3-1.7, administer 1 unit of
fresh frozen plasma and administer 2 units if the INR is 1.7-2.0.
4. The following approaches can be used: administer full-dose
anticoagulation with IV unfractionated heparin (UFH); administer
full-dose anticoagulation with LMWH; or administer prophylactic
doses of UFH or LMWH.
50. 2. Invasive surgery is generally safe (from major
hemorrhagic complication) when the INR ∼1.5.
3. It takes approximately 4 days for the INR to reach 1.5
once oral anticoagulant is stopped preoperatively.
4. It takes approximately 3 days for the INR to reach 2.0
once oral anticoagulant is restarted postoperatively.
5. If oral anticoagulant is held 4 days pre-op and started
immediately post-op, the patient is, in the mean time,
without anticoagulation for 2 days
52. The ultimate goals of preoperative medical assessment are to reduce the
patient’s surgical and anesthetic perioperative morbidity or mortality, and to
return him to desirable functioning as quickly as possible. It is imperative to
realize that “perioperative” risk is multifactorial and a function of the
preoperative medical condition of the patient, the invasiveness of the surgical
procedure and the type of anesthetic administered
Laboratory investigations should be ordered only when indicated by the
patient’s medical status, drug therapy, or the nature of the proposed procedure
and not on a routine basis
Proper consultations with appropriate medical services should be obtained to
improve the patient’s health. These consultations should ideally not be done in
a “last second” fashion
53. I. Ronald d miller. Anesthesia. Fifth edition
II. Wylie and churchill-davidson’s Apractice of anesthesia
III. HIPPOKRATIA 2007, 11, 1: 13-21
IV. How to read an electrocardiogram (ECG). Part One: Basic principles of the ECG. The
normal ECG. SSMJ Vol 3 Issue 2 May 2010
V. Precautions for Patients on Steroids Undergoing Surgery
VI. How to Read a Chest X-Ray – A Step by Step Approach . SSMJ Vol 1 Issue 2.
VII. Clinical Guideline for the Perioperative Steroid Replacemen
VIII. Preoperative evaluation of the patient with pulmonary disease. Rev Bras Anestesiol.
2014;64(1):22---34
IX. Pulmonary Function Tests.Harpreet Ranu, Michael Wilde, Brendan Madden. Ulster Med J
2011;80(2):84-90
Notas del editor
Open surgery - an "open" surgery means the cutting of skin and tissues so that the surgeon has a full view of the structures or organs involved. Examples of open surgery are the removal of the organs, such as the gallbladder or kidneys.
Minimally invasive surgery - minimally invasive surgery is any technique involved in surgery that does not require a large incision. This relatively new approach allows the patient to recuperate faster with less pain. Not all conditions are suitable for minimally invasive surgery.
Hish risk procedures,
Red blood cell count, hemoglobin and hematocrit. The results of your red blood cell count, hemoglobin and hematocrit are related because they each measure aspects of your red blood cells.
If the measures in these three areas are lower than normal, you have anemia. Anemia causes fatigue and weakness. Anemia has many causes, including low levels of certain vitamins or iron, blood loss, or an underlying condition.
A red blood cell count that's higher than normal (erythrocytosis), or high hemoglobin or hematocrit levels, could point to an underlying medical condition, such as polycythemia vera or heart disease.
White blood cell count. A low white blood cell count (leukopenia) may be caused by a medical condition, such as an autoimmune disorder that destroys white blood cells, bone marrow problems or cancer. Certain medications also can cause white blood cell counts to drop.
If your white blood cell count is higher than normal, you may have an infection or inflammation. Or, it could indicate that you have an immune system disorder or a bone marrow disease. A high white blood cell count can also be a reaction to medication.
Platelet count. A platelet count that's lower than normal (thrombocytopenia) or higher than normal (thrombocytosis) is often a sign of an underlying medical condition, or it may be a side effect from medication. If your platelet count is outside the normal range, you'll likely need additional tests to diagnose the cause.
In a test tube during a laboratory test, there are two "pathways" that can initiate clotting, the so-called extrinsic and intrinsic pathways. Both of these then merge into a common pathway to complete the clotting process. The PT test evaluates how well all of the coagulation factors in the extrinsic and common pathways of the coagulation cascade work together. Included are: factors I (Fibrinogen), II (Prothrombin), V, VII and X. The PTT test evaluates those protein factors that are part of the intrinsic and common pathways: XII, XI, IX, VIII, X, V, II (prothrombin), and I (fibrinogen) as well as prekallikrein (PK) and high molecular weight kininogen (HK). The PT and PTT evaluate the overall ability to produce a clot in a reasonable amount of time and, if any of these factors are deficient in quantity or not functioning properly, the test results will be prolonged
The INR is a calculation that adjusts for changes in the PT reagents and allows for results from different laboratories to be compared. Most laboratories report both PT and INR values whenever a PT test is performed. The INR should be only applicable, however, for those taking the blood-thinning medication warfarin.
For calculating the international normalized ratio, a patient's prothrombin time is divided by the mean normal prothrombin time. This ratio is raised to a power called the international sensitivity index
Calculating the ISI
The calibration of a test thromboplastin must be against a reference thromboplastin of the same species e.g. human against human, rabbit against rabbit etc.Prothrombin Times are performed in duplicate for each thromboplastin and the mean for each pair of tests derived. Tests are historically performed on 20 normal donors not on anticoagulants and 60 patients who have been on oral anticoagulant treatment for at least 6 weeks. If there is more than a 10% difference in the clotting times between duplicate samples, the tests on that plasma sample should be repeated.The mean of each pair of of PT results are plotted on double-log paper with the reference sample on the Y axis and the test plasma on the X-axis. The use of the double-log paper removes the necessity to derive the log for each PT result. A line of best fit is drawn and the slope of this line is the ISI.
various conditions may prolong or shorten prothrombin time.
Causes of prolonged PT include the following:
Warfarin use
Vitamin K deficiency from malnutrition, biliary obstruction, malabsorption syndromes, or use of antibiotics
Liver disease, due to diminished synthesis of clotting factors
Deficiency or presence of an inhibitor to factors VII, X, II/prothrombin, V, or fibrinogen
Disseminated intravascular coagulopathy (DIC)
Fibrinogen abnormality (eg, hypofibrinogenemia, afibrinogenemia, dysfibrinogenemia)
After bolus administration of heparin (PT may be transiently elevated)
Massive blood transfusion due to dilution of plasma clotting proteins
Hypothermia, as it causes inhibition of a series of enzymatic reactions of the coagulation cascade [1]
Causes of decreased PT include the following:
Vitamin K supplementation
Fresh frozen plasma transfusion
Patients’ risk factors are usually subdivided into three categories: major, intermediate and minor .A 6-week period is necessary for the myocardium to heal after an infarction and for the thrombosis to resolve.
Patients with coronary revascularization done within the preceding 40 days should also be classified as high-risk patients. Because of sympathetic stimulation and hypercoagulability during and after surgery, patients with major
predictors have a five times greater perioperative risk. Only vital or emergency surgical procedures should
therefore be considered for these patients. All elective operations should be postponed and the patients properly
investigated and treated.
Intermediate-risk factors are proof of well established but controlled coronary artery disease. Diabetes mellitus is included in this category because it is frequently associated with silent ischemia and represents an independent risk factor for perioperative mortality.
Minor risk factors are markers of an increased probability of coronary artery disease, but not of an increased perioperative risk
ETT consists of exercising on a treadmill following a defined protocol, the Bruce protocol, over approximately 20 minutes. The test begins gently and gradually the level of intensity is increased through a combination of increased treadmill speed and incline.
Intensity of exercise is measured in metabolic equivalents (METs) where 1 MET is the amount of energy expended at rest or 3.5 ml oxygen per kilogram per minute.
The test is divided into seven stages of three minutes and there is also a less strenuous version called the modified Bruce.
ECG is recorded throughout and blood pressure measured intermittently.
ETT might be prematurely stopped for any of the following: development of chest pain, presence of ST elevation, very deep, 2 mm or more, ST depression, arrhythmias, hypotension or if the patient becomes tired and is unable to continue. In addition, elevation of blood pressure to dangerous levels such as >250/115 mm Hg should also lead to termination of the test.
Beta-blockers and digoxin can interfere with the results so are usually stopped before the ETT.
Chest radio graphs helps to determine
Any tracheal deviation
Mediastinal masses
Pulmonary nodules
Solitary lung mass
Aortic aneurysm
Pulmonary edema
Pneumonia
Ateòectasos
Any fractures of vertebrae, ribs or clavicle,
Cardio megaly
on he down side the radio graphs cant tell degree of chronic lung diseas that would require changes in anesthesia technique than what has been decided upon after medical and history taking
In a conventional 12-lead ECG, 10 electrodes are placed on the patient's limbs and on the surface of the chest. The overall magnitude of the heart's electrical potential is then measured from 12 different angles ("leads") and is recorded over a period of time (usually 10 seconds). In this way, the overall magnitude and direction of the heart's electrical depolarization is captured at each moment throughout the cardiac cycle.[1] The graph of voltage versus time produced by this noninvasive medical procedure is referred to as an electrocardiogram.
heart has an orderly progression of depolarization that starts with pacemaker cells in the sinoatrial node, spreads out through the atrium, passes through the atrioventricular node down into the bundle of His and into the Purkinje fibers, spreading down and to the left throughout the ventricles. This orderly pattern of depolarization gives rise to the characteristic ECG tracing.
To briefly summarize the components of a normal ECG tracings, it consist of waveform components which indicate electrical events during one heart beat. These waveforms are labeled P, Q, R, S, T and U. P wave is the first short upward movement of the ECG tracing. It indicates that the atria are contracting, pumping blood into the ventricles. The QRS complex, normally beginning with a downward deflection, Q; a larger upwards deflection, a peak (R); and then a downwards S wave. The QRS complex represents ventricular depolarization and contraction.The PR interval indicates the transit time for the electrical signal to travel from the sinus node to the ventricles.
–– 10 electrodes required to produce 12-lead ECG.– – Electrodes on all 4 limbs (RA, LL, LA, RL)– – Electrodes on precordium (V1–6)– Monitors 12 leads (V1–6), (I, II, III) and (aVR, aVF, aVL)– Allows interpretation of specific areas of the heart– – Inferior (II, III, aVF)– – Lateral (I, aVL, V5, V6)– – Anterior (V1–4)
Uses 5 electrodes (RA, RL, LA, LL and Chest)– Monitor displays the bipolar leads (I, II and III)– AND a single unipolar lead (depending on position of the brown chest lead (positions V1–6))
Uses 3 electrodes (RA, LA and LL).
– Monitor displays the bipolar leads (I, II and III)
– To get best results – Place electrodes on the chest wall equidistant from the heart (rather than the specific limbs)
The adrenal suppression caused by steroid therapy. [1] This often poses the greatest risk and
deserves particular attention. It is important for patients to be educated about the risk. [2] Steroid cards
should be carried by patients taking steroids.
The disease or condition which required them to take steroids. Corticosteroids are used in a
wide variety of conditions. Some of these may also have attached risks for anaesthesia (those, for
example, affecting lungs, neck joints or drug metabolism).
Long-term and other side-effects of steroid therapy. These include:
Hypertension.
Diabetes mellitus.
Fatty liver.
Susceptibility to infection.
Osteoporosis.
Avascular necrosis of bone.
Skin sepsis.
Electrolyte disturbance: hypokalaemia, metabolic alkalosis.
Establish how much steroid has been taken and for how long. The degree of adrenal suppression
depends on the dose and duration of steroid treatment. However, the integrity of the adrenal response
is not routinely tested and steroid cover or supplements are given according to the surgical stimulus
(minor, moderate and major surgery).
Dosages of less than 5 mg prednisolone per day are not significant and no steroid cover is required.
10 mg/day or more of prednisolone (or equivalent) is generally taken as the threshold dose for 'steroid
cover'.
Steroid cover is required if taken within three months of the surgery. This is because adrenal
suppression can occur after only a week and may take as long as three months to recover.
Peri-operative considerations
Normal cortisol secretion is about 30 mg/day. The normal rise in plasma adrenocorticotropic hormone
(ACTH) and hence cortisol is in response to the severity of surgery. The adrenals are capable of
secreting about 300 mg/day (equivalent to about 75 mg of prednisolone) but output rarely exceeds 150
mg of cortisol/day even in response to major surgery.
Postoperative considerations
The normal rise in cortisol secretion after surgery lasts for about three days. In recent years, doses
used for steroid cover have been reduced. [3] This is because excessive doses cause adverse effects
such as postoperative infection, gastrointestinal haemorrhage and delayed wound healing.
Minor surgery - 25 mg hydrocortisone at induction of anaesthesia and then resume normal
medication postoperatively.
Moderate surgery - usual dose of steroids pre-operatively and then 25 mg of hydrocortisone
intravenously (IV) at induction, followed by 25 mg IV every 8 hours for 24 hours. Usual pre-operative
dose is then continued.
Major surgery - usual dose of steroids pre-operatively, then a bigger 50 mg of hydrocortisone IV at
induction, followed by 50 mg IV every 8 hours for 48-72 hours. Continue this infusion until the patient
has started light eating, then restart the normal pre-operative dose.