Download MBBS Neuroanaesthesia PPT 6 Preoperative Risk Stratification And Optimization Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Neuroanaesthesia PPT 6 Preoperative Risk Stratification And Optimization Lecture Notes

Preoperative Risk Stratification and Patient

Optimization for Elective surgeries

Preoperative evaluation

? Surgical procedures performed under anaesthesia require

preoperative evaluation

- Anaesthesia is an added risk to surgery
- Preanaesthetic evaluation of patients improve clinical safety
- Minimizes morbidity in appropriately prepared patient
Purpose

? To obtain pertinent information regarding.

? The patient's medical history,
? Formulate an assessment of the patient's

perioperative risk

? Develop a plan for any requisite clinical

optimization.

? Planning postoperative pain management in the

background of preoperative pain medication

Goals of Preoperative evaluation

? To ensure that patients can safely tolerate

anaesthesia for planned surgical procedures

? To mitigate risks associated with the overall

perioperative period
Scope of Preoperative Evaluation


? General History (leading question based)
? Physical examination
? Evaluation of coexisting disease
? Preop lab and diagnostic investigations
? Preop medication management
History

vCorrect diagnosis can be made in 56% of

cases on the basis of history alone

? History in general
? History of coexisting medical illnesses
? History of taking medicine
? History of allergies and drug reactions
? Anaesthetic history
? Family History

Physical examination

? Special attention to the evaluation of the

? vital signs, (CNS, heart, lung,)
? Airway,
?If regional anaesthesia is proposed :

? Assessment of the site of block
? Back
Height and weight

? Calculate BMI : obese
? Estimate drug dosages
? Determine fluid volume requirement
? Calculate acceptable blood loss
? Adequacy of urine output

Vital signs

? Blood pressure
? Resting pulse
- rate, rhythm, and fullness
? Respiration
- rate, depth, and pattern at rest
? Body temperature
? Pain score (baseline score)
Airway Examination

? Mallampati classification
? Interincisors gap
? Thyromental distance
? Forward movement of mandible
? Range of cervical spine motion :
flexion and extension
? Document loose or chipped teeth,
tracheal deviation

Preoperative Evaluation Of

Patients With Coexisting Disease

? Identification of these comorbid conditions often

presents an opportunity for the anaesthesiologist to
intervene to decrease risk

? These conditions are best managed before the

surgery, thus allowing ample time for thoughtful
evaluation, consultation, and optimization.
Cardiovascular system

? May lead to serious perioperative adverse events

? Cardiovascular complications account for almost half

of the perioperative mortalities

? Serious myocardial injury occurs in approximately

80% of patients who undergo major surgery

? Some perioperative interventions modify risks for

cardiovascular morbidity and mortality

Cardiovascular disorders

? Hypertension
? Ischemic heart disease
? Heart failure
? Valvular heart disease
? Patients with rhythm disturbances
? Patient with coronary stents
? Patients with pacemakers and ICD devices
? Patients with peripheral arterial disease
The Revised Cardiac Risk Index (RCRI) has been
extensively validated for predicting perioperative cardiac
risk in noncardiac surgery

METS
Fliesher et al. "2014
ACC/AHA Guideline
on Perioperative
Cardiovascular
Evaluationand
Management of Patients
Undergoing Noncardiac
Surgery."
http://content/onlinejac
c.org/
Respiratory system
? Respiratory function is inextricably linked to practice

of anaesthesia

? GA has significant effects on respiratory function and

lung physiology and mechanics

? Adverse respiratory event can occur during

anaesthesia and the most significant is hypoxemia

? Integrative measures of respiratory function are likely

predictors of outcome following anaesthesia and
surgery

Pulmonary disorder

? Upper respiratory tract infection
? Asthma and COPD
? Chronic smokers
? Restrictive lung diseases
? Obstructive sleep apnoea
? Patients scheduled for lung
resection
Endocrine system

? Diabetes Mellitus
? Thyroid disorders
? Hypothalamic- pituitary- adrenal disorders
? Pheochromocytoma

Renal system

? Surgical stress, anaesthetic agents tend to decrease

GFR

? Renal impairment- CKD
- AKI
? Contrast induced nephropathy

? The emphases of the preoperative evaluation of

patients with renal insufficiency are on the

cardiovascular system, cerebrovascular system, fluid

volume, and electrolyte status
Hepatic disorder

? Liver diseases have significant impact on drug

metabolism and pharmacokinetics

? Sedatives./opioids might have exaggerated effects in

patients with advanced liver disease

? Hepatitis
? Alcohol liver disease
? Obstructive jaundice
? Cirrhosis

Hematologic Disorders

? Anaemia
? Sickle cell disease
? G6PD deficiency
? Coagulopathies
Neurologic disease

? Cerebrovascular disease
? Seizure disorders
? Multiple sclerosis
? Aneurysm and AV malformation
? Parkinson disease
? Neuromuscular junction disorders
? Muscular dystrophy and myopathy
Musculoskeletal and Connective tissue disorders

? Rheumatoid Arthritis
? Ankylosing Spondylitis
? Systemic Lupus Erythematosus
? Raynaud Phenomenon

Miscellaneous conditions

? Morbidly obese patient
? Patient with transplanted organs
? Patient with allergies
? Patient with substance abuse
Specific group of patient

? Children
? Pregnant patient
? Breast feeding patient
? Elderly patient

Preoperative laboratory and diagnostic studies

? To screen the disease
? To evaluate fitness for surgery
? Should be based on patient's medical history and

proposed surgical procedure
Preoperative diagnosis based investigations

before elective surgery

Preoperative risk assessment

? A critical objective for the preanaesthesia evaluation
? Improves patients' understanding of the risks inherent

to the perioperative period

? Helps health care providers for clinical decision

making

? Helps to identify individuals who warrant potentially

beneficial interventions, enhanced levels of

postoperative monitoring, or consideration for

alternative nonoperative treatment for their

underlying condition
Risk stratification

? Meyer Saklad et al- 1941, described `six degree' ASA

PS grading of a patient's physical state as just one of

the components of the operative risk

? He listed the other components as:
-The planned surgical procedure
-The ability and skill of the surgeon in the particular
procedure contemplated
- The attention to postoperative care
- The past experience of the anaesthetist in similar
circumstances

Influences of various components on poor perioperative

outcome

Preoperative medication management

? Medications: to continue or not?
? Need to understand risk/ benefit of continuing or holding

a medication

? Diuretics, ACE Inhibitors, ARBS
- should be discontinued 12-24 hr prior to surgery to prevent
intraoperative hypotension
? Nitrates, Digoxin, Clonidine, Beta Blockers, Calcium

Channel Blockers, and Antiarrhythmic drugs

-Essentially safe to continue perioperatively

Planning for postoperative pain management

? All patients have the right to appropriate assessment

and treatment of pain

? A preoperative evaluation should include baseline

pain assessment

? Provides an important opportunity to discuss and plan

for the management of acute postoperative pain

? Specific issues include their tolerance to usual doses

of opioid analgesics and the potential for acute
withdrawal reactions should be assessed

Collaboration, Commitment and Team work

? The preoperative evaluation clinic is a visible partnership among the

departments of anaesthesia, surgery, nursing, and hospital administration to
achieve common goals
Summary

Surgeries done (w.e.f 3/6/14 till date)

LA, 930

GA, 901

? OPD based Preoperative

evaluation was done

? Grave morbidity- 7 cases

(0.003%)

Regional213