This document outlines the process and importance of preanesthetic evaluation. It defines preanesthetic evaluation as a medical check-up and lab tests done before surgery to assess patient health and risks. The evaluation aims to optimize patient preparation, ensure surgery is realistic, and anticipate problems. It involves taking a medical history, examining the patient, ordering relevant tests, and developing a preoperative plan. Factors like ASA grade and POSSUM score can help predict perioperative risks. The evaluation helps educate patients, organize care, and plan anesthesia to improve surgical outcomes.

1. By
Dr olofin K.E
Anaesthetic Unit
Asokoro District Hospital

2. Outline
Introduction
Definition
Aims
Preanesthetic evaluation
Preanesthetic planning
Premedication and other prophylactic measures
Prediction of perioperative morbidity or mortality
Conclusion
References

3. Introduction
 All patients scheduled to undergo surgery should be
assessed in advance with a view to planning optimal
preparation and perioperative management.
 It is one mechanism by which the standard and
quality of care provided by the anaesthetist is
measured.

4. Definition
 Preanesthetic evaluation is a medical check-up and
laboratory investigations done by the anaesthesiologist
before an operation, to assess the patient's physical
condition and any other co-morbidities.

5. Aims
 To create rapport with the patient
 To ensure history, physical examination and proper
investigation optimise patient for anaesthesia.
 To confirm that the surgery proposed is realistic and
beneficial to the patient and the possible risks
involved.
 To anticipate potential problems and adequately plan
for them

6. Preanesthetic assessment
History
 Bio data: Age, gender
 Indication for surgery
 Surgical/Anaesthetic Hx: previous anaesthesia, surgery
and complications
 PMHx
hypertension, diabetes, asthma, sickle cell disease etc

7. Preanesthetic assessment
 Drug Hx. Medications, drug allergies,
 F/SHx: Cigarette smoking, alcohol consumption, use
of recreational drugs

8. Preanesthetic assessment
General examination
• General assessment of nutrition and mental status
Systemic examination
• CNS, CVS, and respiratory systems

9. Preanesthetic assessment
Airway assessment
It is done to determine intubation difficulty (no single
test is 100% specific or sensitive)
Relative to tongue/pharyngeal size using the
mallampatti classification.

10. Preanesthetic assessment
Mallampati classification
• Class I : Visualization of the
soft palate, fauces; uvula,
anterior and the posterior
pillars.
• Class II : Visualization of the
soft palate, fauces and uvula.
• Class III : Visualization of
soft palate and base of uvula.
• Class IV: Only hard palate is
visible. Soft palate is not
visible at all.

13. Preanesthetic assessment
Atlanto occipital joint (AO) extension
• Grade I : >35°
• Grade II : 22°-34°
• Grade III : 12°-21°
• Grade IV : < 12°
• Normal angle of extension is 35° or more

14. Preanesthetic assessment

15. Preanesthetic assessment
"3-3-2 rule"
A. Inter-incisor distance- (<3
finger breadths is associated
with difficulty in intubation)
B. Š
Hyomental distance (distance
of lower mandible in midline
from the mentum to the hyoid
bone); <3 finger breadths (<6
cm) is associated with difficult
intubation
C. Š
Thyrohyoid distance (<2
finger breadths is associated
with difficult intubation)

18. Preanesthetic assessment
LEMON airway assessment method
 The score with a maximum of 10 points is calculated by
assigning 1 point for each of the following LEMON
criteria:

19. Preanesthetic assessment
 L = Look externally (facial trauma, large incisors, beard
or moustache, large tongue)
 E = Evaluate the 3-3-2 rule
 M = Mallampati (Mallampati score > 3).
 O = Obstruction (presence of any condition like
epiglottitis, peritonsillar abscess, trauma).
 N = Neck mobility (limited neck mobility)

20. Preanesthetic assessment
Others
• Š
Anterior jaw subluxation (<1 finger breadth is
associated with difficult intubation)
• ƒ
Tongue size dentition, dental appliances/prosthetic
caps, existing chipped/loose teeth – must inform
patients of rare possibility of damage
• ƒ
Nasal passage patency (if planning nasotracheal
intubation)

21. Preanesthetic assessment
 examination of anatomical sites relevant to lines and
blocks
 ƒ
bony landmarks and suitability of anatomy for
regional anaesthesia (if relevant)
 ƒ
sites for IV, central venous pressure (CVP), and
pulmonary artery (PA) catheters

22. Preanesthetic assessment
Investigations
 FBC,Urinalysis, Urea, creatinine and electrolytes Blood
glucose, Liver function tests, Coagulation screen, ECG,
Chest X-ray
 Others: Echocardiography, Pulmonary Function Tests,
Cardiopulmonary Exercise Testing

23. Preanesthetic preparation
Having taken
 Full clinical history,
 Physical examination
 Reviewed the relevant investigations,
 Satisfied?
 Go ahead with surgery or reschedule

24. Preanesthetic preparation
 Preoperative fasting
 providing information to the patient and obtaining
consent to proceed
 Ensuring blood products are available during the
perioperative period if necessary
 organizing appropriate staff and equipment within the
operating theatre suite.
 Reschedule Surgery for Clinical Reasons

25. Preanesthetic preparation
Reasons include
 Acute upper respiratory tract infection
 Coexisting medical disease and drug therapy,
 Emergency surgery for which the patient has not been
resuscitated adequately
 Recent ingestion of food
 Failure to obtain consent

26. Premedication and other prophylactic
measures
Premedication refers to the administration of drugs in
the period 1–2 h before induction of anaesthesia.
Aim:
 allay anxiety and fear
 reduce postoperative nausea and vomiting
 assist with intra- and postoperative analgesia
 reduce secretions

27. Premedication and other
prophylactic measures
 reduce the volume and increase the pH of gastric
contents
 attenuate vagal reflexes
 attenuate sympathoadrenal responses.

28. Premedication and other
prophylactic measures
Pre-anesthetic medications to stop
 ƒ
oral antihyperglycemics: stop on morning of surgery
 ƒ
antidepressants: stop on morning of surgery
 ƒ
ACE inhibitors and angiotension receptor blockers: may
stop on morning of surgery (controversial)
 ƒ
anticoagulants

29. Prediction of perioperative morbidity or
mortality
 ASA (American Society ofAnesthesiologists) Grading
 Physiological and Operative Severity Score for the
enUmeration of Mortality and morbidity POSSUM score
 Lee’s Revised Cardiac Risk Index

32. Conclusion
Assessments made during the preanesthetic
evaluation may be used to:
• Educate the patient
• Organize resources for perioperative care
• Formulate plans for intra-operative care, postoperative
recovery, and postoperative pain management.

33. Conclusion
 These would help the patient and family prepare for
the best possible outcome.
 Failure to undertake this activity places the patient at
increased risk of perioperative morbidity or mortality.

34. References
 Smith and Aitkenhead’s Textbook of Anaesthesia Sixth
Edition By Alan R. Aitkenhead, Iain K. Moppett And
Jonathan P. Thompson
 Airway Assessment : Predictors Of Difficult Airway ,Dr.
Sunanda Gupta1 Dr. Rajesh Sharma Kr2 Dr. Dimpel Jain
 2016 Toronto Notes, Comprehensive medical reference and
review for the Medical Council of Canada Qualifying Exam
Part I and the United States Medical Licensing Exam Step 2
32nd Edition, Editors-in-Chief: Zamir Merali and Jason D.
Woodfine

35. Thank you