to give an idea about conscious sedation

1. What we need to know about
Conscious Sedation
BY
Rizk Elazhary
MD, Anesthesiology
Benha University

2. Introduction and definition
Conscious Sedation: A drug induced depression of the patient’s
level of consciousness such that the patient responds appropriately to
physical and verbal commands and maintains airway protective
reflexes, that is intended to facilitate the successful performance of
the diagnostic or therapeutic procedure while providing patient
comfort and cooperation.

3. Purpose of the lecture
Dissemination of medical knowledge
Fulfill requirements for conscious sedation understanding
and privileges
Differentiate conscious sedation from light sedation, deep
sedation and general anesthesia.
Describe the desired outcomes of conscious sedation.

4. Purpose of the lecture (continue)
Record the normal dosage, rate of administration, onset
and duration of action and adverse effects of specific
pharmacologic agents used in conscious sedation.
Describe the correct technique for administering reversal
agents.
Identify potential complications related to conscious
sedation

5. Target Audience
Attending staff who wish to be credited in
conscious sedation.
Anyone who cares conscious sedation also
requires current ACLS certification.

6. Indications
Any procedure where the patient will be
unable to cooperate, and that procedure may
cause the patient significant pain

7. Clinical Areas Administering Sedation
OR and ICU : for GIT endoscopies & ECT.
Emergency Room.
Delivery Room.
Radiology Department.
Uro-surgery, ESWEL unite.
Others: Orthopedic , Cardio-Thoracic

8. Levels of Sedation
Light Sedation
 The administration of
medication in dosages
causing the sedation and
allowing the patient to
sleep and rest.
Moderate Sedation
 A medically controlled
state of depressed
consciousness that allows
the patient to
independently maintain a
patent airway and respond
to verbal stimuli.
Deep Sedation
 A medically controlled state
of depressed consciousness
from which the patient is not
easily aroused, is unable to
maintain a patent airway
independently, and is unable
to respond purposefully to
physical stimulation or verbal
command.
General Anesthesia
 A medically controlled state
of unconsciousness which
includes loss of protective
reflexes and inability to
respond to stimuli.

9. Goals of Sedation
To titrate the medication such that the
smallest amount of medication is administered
to achieve the desired depression of
consciousness while minimizing the potential
complications.
Desired Effects:
Depressed consciousness
Amnesia
Maintaining the patient vital signs

10. Eligible Patients
Patients with the following indications
Stable vital signs
NPO
No medical contraindications to the medications that
will be given
ASA 1 & ASA 2
Malampati I or II

11. Fasting Recommendations
Ingested Material minimum fasting hours
Clear Liquids 2 h
Breast milk 4 h
Infant formula 6 h
Non-human milk 6 h
Light meal 6 h
Heavy meal ≥ 8 h

12. Physical Status Classifications

13. ASA Classification
ASA 1 ---Normally healthy patient
ASA 2 --- Mild systemic disease --- no functional
limitation (e.g. hypertension, diabetes mellitus,
chronic bronchitis, morbid obesity, extremes of age)

14. Classifications (continued)
ASA 3 --- Severe systemic disease that results
in functional limitation (e.g. poorly controlled
hypertension, diabetes mellitus with vascular
complications, angina pectoris, prior
myocardial infarction, pulmonary disease that
limits activity.
ASA 4 --- Severe systemic disease that is a
constant threat to life (e.g. congestive heart
failure, unstable angina pectoris, renal or
hepatic dysfunction)

15. Classifications (continued)
ASA 5 --- Moribund patient not expected to
survive without the operation (e.g. ruptured
abdominal aneurysm, pulmonary embolism, head
injury with increased intracranial pressure)
ASA 6 --- A declared dead patient whose organs
are being removed for donation.

16. Mallampati Classification
 Class 1: Full visibility of tonsils, uvula and soft palate
 Class 2: Visibility of hard and soft palate, upper portion of tonsils and
uvula
 Class 3: Soft and hard palate and base of the uvula are visible
 Class 4: Only hard palate is visible
The Mallampati classification is
used to predict the ease of
intubation.
A high Mallampati score (class 3 or
4) is associated with more difficult
intubation as well as a higher
incidence of sleep apnea.

17. “At Risk” Patients for Sedation or Analgesia
The ASA physical status risk classification of 3 or greater
Critical care patients
Extremes in age (<1 or >70 years of age)
Patients with chronic respiratory disease, chronic
obstructive pulmonary disease, emphysema
History of sleep apnea
Mentally and neurologically handicapped patients
Patients at risk for aspiration (i.e. hiatal hernia with
regurgitation, diabetes with gastroparesis
Altered mental status

18. Technique of conscious sedation
The procedure begins once oxygen is given via nasal
cannula, the intravenous (IV) access established,
skin sensitivity test for local anesthetic done,
cardiopulmonary and other required monitors
connected.

19. Complications
Deep unarousable sleep
Hypotension
Arrhythmias
Agitation and, or confusion
Hypoventilation, Respiratory depression , or
Apnea
Airway obstruction
Vomiting and aspiration

20. Contraindications
Physical Examination
Respiratory distress (wheezing, stridor, etc.)
Hypotension
Morbid obesity
Craniofacial abnormalities
Short neck
Decreased hyoid-mental distance (<3cm in adult)
Distorted landmarks on anterior surface of neck

21. Contraindictions (continued)
Physical Examination
Limited mouth opening
Receding chin
Large tongue
Unable to view base of uvula with mouth open and
tongue protruding

22. Monitoring of Patients

23. Monitoring of Patients
Personnel
*Nurse or *physician other than the physician
performing the procedure
Team member able to establish an airway, provide
positive pressure ventilation (Ambu bag)
Mechanism for additional personnel with Advanced
Life Support capability
*ACLS required for physicians and nurses

24. Monitoring of Patients (continued)
Record:
Blood pressure
ECG
Pulse oximetry
Respiratory rate & depth of respiration
Supplemental oxygen throughout procedure
Level of consciousness—ask simple questions
Medications – dose & times

25. Monitoring of Patients (continued)
Record
Supplemental oxygen throughout procedure
Level of consciousness—ask simple questions
Medications – dose & times

26. Ramsey Sedation Scale
Level of Sedation Clinical Description
1 – Anxious, bordering
2 – Cooperative, oriented, tranquil
3 – Responds only to verbal commands
4 – Asleep with brisk response to light stimulation or
physical stimuli
5 – Asleep with sluggish response to stimulation
6 – Asleep with no response to stimulation
**Levels 2, 3 and 4 are desired range of levels during moderate sedation

27. Emergency Resuscitative Equipment
should be available

28. Emergency Equipment
Oxygen – system can deliver 100% at 10 LPM
Suction – can produce negative pressure of 150 torr
Airway management
Face masks (all sizes)
Oral & nasal airways
LMAs (laringeal mask airway)
Endotracheal tubes
Laryngoscopes

29. Emergency Equipment (continued)
Ambu bag
Monitors: (audible & visible display)
 Pulse oximeter
ECG
Automated blood pressure device

30. Emergency Equipment (continued)
Defibrillator with ECG recording capability
Emergency crash cart and ACLS protocols
Emergency drugs include
Naloxone (Narcan)
Flumazenil (Anixate)
Ephedrine
Epinephrine

31. Medications used for conscious
sedation

32. Sedatives/Hypnotics
Midazolam
(Benzodiazepine)
Diazepam
(Benzodiazepine)
Methohexital
(Barbiturate)
Initial IV Dosage
(Adult)
1-2mg
(0.02-0.04 mg/kg)
½ -2 ½ mg 0.75 -1.0 mg/kg
Incremental Dosage
(Adult)
1 mg at 5 minute
intervals
0.5-1.0 mg in 10
minutes
0.25 mg/kg in 5-10
minutes
Pediatric Dosage 0.0250.05 mg’kg
followed by 0.02-0.03
mg/kg at 5 minute
intervals
0.1 mg/kg IV May
repeat q 15 minutes
until desired effect
achieved
0.75-1.0 mg/kg
Onset 1-2 minutes 2-5 minutes <1 minute
Duration 30 minutes 4-6 hours 5-10 minutes

33. Sedatives/Hypnotics (continued)
Midazolam
(Benzodiazepine)
Diazepam
(Benzodiazepine)
Methohexital
(Barbiturate)
Side Effects ↓BP
Respiratory
depression with
rapid
administration
↓HR/↓BP
Respiratory
depression
↓BP ↑HR
Emergence
Delirium, hiccups,
laryngospasm
Contraindications
and Comments
Reduce dosage by
50% in elderly
patients
Pregnancy
Narrow angle
glaucoma
Porphyria
Cardiovascular
Disease shock
Reversal Agent Flumazenil
0.2-1 mg IV
Flumazenil
0.2 mg-1 mg IV
NONE

34. Narcotic Analgesics
Morphine Meperidine Fentanyl
Initial Dosage 5-10 mg IV 0.5-1 mg/kg 0.51.5 mcg/kg
Incremental
Dosage
0.02-0.1 mg/kg/5-10
minute intervals
0.5 mg/kg/5
minute intervals
0.50 mcg per dose at
2-3 minute intervals
Pediatric
Dosage
0.1 mg/kg oral
0.03 -0.05 mg/kg IV
0.5-1 mg/kg 1 mcg/kg followed by
0.25-1.5 mcg/kg at
2-3 minute intervals
Onset 2-5 minutes 1-5 minutes 1-2 minutes

35. Narcotic Analgesics (continued)
Morphine Meperidine Fentanyl
Duration 2-6 hrs 2 hrs 20-30 minutes
Side Effects ↓ HR / ↑BP
Respiratory
depression
↓ HR / ↓ BP
Respiratory
depression
↓ BP
Respiratory
depression
Anaphylaxis
Muscular rigidity
Contraindications &
Comments
Head injury Head injury Use with caution in
patients with reactive
airway disease
Reversal Agents Naloxone 0.4 mg IV Naloxone 0.4 mg IV Naloxone 0.4 mg IV

36. Midazolam
A short-acting, water-soluble benzodiazepine,
an ideal agent for its amnestic and anxiolytic
properties.
Midazolam, with a half-life of 2 hours, has limited
cardiovascular effects, allows for quick recovery and
has no postoperative sequelae such as nausea and
vomiting.
Dose: 0.05 mg/kg bolus IV.

37. Propofol
A rapidly-acting sedative and hypnotic agent having a
quick recovery property.
Can be used in bolus and infusion dose along with
local anesthetic injection.
Slow administration maintains hemodynamics.
Does not cause postoperative nausea or vomiting .
May cause postoperative shivering.
Dose: Bolus - 0.5-1 mg/kg; infusion - 25 µg/kg/min

38. Ketamine
Agent of choice as an analgesic in conscious sedation.
Produces dissociated anesthesia.
Psychotic reactions such as hallucination, serious
cardiovascular adverse effects, seizures and
postoperative shivering have been reported.
Dose: 2 mg/kg IV or 6-10 mg/kg IM.

39. Dexmedetomidine
Has both sedative and analgesic properties.
 Does not cause respiratory depression, though
hemodynamic parameters need to be closely
monitored.
Has a high incidence of postoperative dry mouth.
Dose: 1 μg/kg IV.

40. The disadvantages of conscious sedation
 Mainly are the lack of airway control and the risk of
airway obstruction or aspiration.
Thus to minimize the disadvantage, the medication
should be selected and titrated by the
anesthesiologist

41. Discharge Criteria
Patient awake and alert to pre-sedation levels
Stable vital signs
Aldrete Score equal to or greater than 8 or equal to
baseline
Patient able to walk unassisted
Discharge to a responsible adult

42. Points to Remember
When appropriately administered, moderate sedation
should make the patient’s procedures tolerable to
pain and reduce anxiety.
Moderate sedation is the responsibility of the
anesthesiologist.
Give drugs “slowly”.
Let “routine” be your friend.

43. What if our patient is pregnant?

44. Conscious sedation in pregnancy
Consider the physiological changes in pregnancy.
Propofol is taken as a safe agent.
 The American College of Obstetricians and
Gynecologists (ACOG) has recommended that
intermittent or continuous fetal monitoring during
conscious sedation is a more sensitive and important
indicator of placental perfusion and fetal oxygenation
than observations of maternal hemodynamic stability.

45. References
• Longnecker DE, Tinker JH, Morgan Jr., GE.
• Principles and Practice of Anesthesiology 1998; Vol. 1:(12) 227-228 and Vol. 2:
(86) 2268.
• Mallampati S, Gatt S, Gugino L, Desai S, Waraksa B, Freiberger D, Liu P
(1985).
• “A clinical sign to predict difficult tracheal intubation; a prospective study”.
• Can Anaesth Soc J 32 (4): 429-34.
• Nuckton TJ, Gledden DV, Browner WS, Claman DM (Jul 1, 2006).
• “Physical examination: Mallampati score as an independent predictor of
obstructive sleep apnea”. Sleep 29 (7); 903-8.
• http://sedationconsulting.blogspot.com/2008/09/guidelines-for-conscious-moder
• JAYASHREE SEN*, BITAN SEN: “Conscious Sedation: An Observation”,
Indian Journal of Clinical Practice, Vol. 24, No. 10, March 2014