1. Clinical Anaesthesiology
Qiu Wei Fan
Associate professor Department of Anaesthesiology Rui Jin Hospital Shanghai Second Medical University

2. Local Anaesthetic techniques
Features of local anaesthesia
Methods of local anaesthesia
Complications of local anaesthesia
Regional block equipment
Spinal, epidural, & caudal blocks
Peripheral nerve blocks

3. Preoperative assessment and premedication Purpose
Establish rapport with the patient
Obtain a history and perform a physical examinations
Order a special investigations
Assess the risks of anaesthesia and surgery and if necessary postpone or cancel the date of surgery
Instutite preoperative management
Prescribe premedication and the anaesthesia management

4. Preoperative assessment and premedication
Routine preoperative anaesthetic evaluation
History
Current problem
Other known problems
Medication history

5. Preoperative assessment and premedication Medication history
Allergies
Drug intolerances
Present therapy
Prescription
Nonprescription
Nontherapeutic
Alcohol
Tobacco
Illicit

6. Preoperative assessment and premedication
Previous anaesthetics, surgery, and obstetric deliverries
Family history
Review of organ systems
Last oral intake

7. Preoperative assessment and premedication Review of organ systems
General
Respiratory
Cardiovascular
Renal
Gastrointestinal
Hematologic

8. Preoperative assessment and premedication Review of organ systems
Neurologic
Endocrine
Psychiatric
Orthopedic
Dermatologic

9. Preoperative assessment and premedication Physical examination
Vital signs
Airway
Heart
Lungs
Extremities
Neurologic examination

10. Preoperative assessment and premedication Laboratory evaluation
Hematocrit or hemoglobin concentration All menstruating women All patients over 60 years of age All patients who are likely to experience significant blood loss and may require transfusion
Serum glucose and creatinine (or blood urea nitrogen) concentration: all patients over 60 years of age
Electrocardiogram: all patients over 40 years of age
Chest radiogram: all patients over 60 years of age

11. ASA classification
I A normal healthy patient other than surgical pathology- without systemic disease.
II A patient with mild systemic disease – no functional limitations.
III A patient with moderate to severe systemic disturbance duo to medical or surgical disease- some functional limitation but not incapacitating.

12. ASA classification
IV A patient with severe systemic disturbance which poses a constant threat to life and is incapacitating.
V A moribund patient not expected to survive 24 hours with or without surgery.
E If the case is an emergency, the physical status is followed by the letter “E”-, “IIE”.

13. American Society of Anaesthesiologists classification and perioperative mortality rates
Class Mortality Rate
I % II % III % IV % V %

14. Documentation Informed Consent The preoperative note
The intraoperative anaesthesia record
The postoperative notes

15. Local Anaesthetic techniques Features of local anaesthesia
Preservation of consciousness
The quality of early postoperative analgesia
Simplicity of administration
Sympathetic blockade attenuation of the stress response
Minimal depression of ventilation

16. Local Anaesthetic techniques Methods of local anaesthesia
Surface anaesthesia
Local infiltration
Field block
Regional blocks (Spinal, epidural, & caudal blocks)
Peripheral nerve blocks

17. Complications of local anaesthesia
Local anaesthetic toxicity( Systemic toxicity): Cardiovascular, Respiratory， Cerebral and Immunologic
Hypotension
Motor blockade
Pneumothorax
Urinary retention
Neurological complications
Equipment problems

18. Local anaesthetic toxicity
Systemic toxicity Cardiovascular:
Cardiac dysrhythmia or circulatory collapse is often the presenting sign of local anaesthetic overdose during anaesthesia.

19. Local anaesthetic toxicity
Systemic toxicity Respiratory:
Lidocaine depresses hypoxic drive. Apnea can result from phrenic and intercostal nerve paralysis or depression of the medullary respiratory center.

20. Local anaesthetic toxicity
Systemic toxicity Cerebral:
Early symptoms are circumoral numbness, tongue paresthesia, and dizziness. Sensory complaints may include tinnitus and blurred vision.Excitatory signs often precede central nerve system depression.

21. Local anaesthetic toxicity
Systemic toxicity Immunologic:
True hypersensitivity reactions to local anaesthetic agents- as distinct from systemic toxicity due to excessive plasma concentration- are quite uncommon.

22. Regional block equipment
Spinal needles (26G)
Pencil-point 24G needles
Catheters
Label syringes
A short length of tubing
Nerve stimulators
Local anaesthetic drugs

23. Complications of local anaesthesia Hypotension
Sympathetic blockade
Total spinal blockade
Vasovagal attack
Anaphylactoid reaction

24. Regional block Subarachnoid block(SAB): Spinal anaesthesia
Extradural nerve block: Epidural anaesthesia may be performed in the sacral(caudal block), lumbar, thoracic or cervical regions.

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40. Regional Block
Physiology: Somatic Blackade Visceral blackade Cardiovascular Pulmonary Gastrointestinal Liver Urinary tract Metabolic & Endocrine

41. Physiology effects of SAB Differential nerve blockade
Sympathetic fibres block
sensory block
Motor block

42. Physiology effects of SAB Respiratory system
Roots of the phrenic nerves: apnoea
Thoracic level: loss of intercostal muscle activity, decrease in vital capacity, reduction in cardiac output and pulmonary artery pressure, and increased ventilation/perfution imbalance, resulting in a decrease in arterial oxygen tension (PaO2)

43. Physiology effects of SAB Cardiovascular system
Denervation of the sympathetic outflow tracts (T1-L2): dilatation of resistance and capacitance vessels and results in hypotension
Bradycardia: vasovagal syndrome; block of the cardiac sympathetic fibres

44. Physiology effects of SAB Gastrointestinal system
Sympathetic denervation and unopposed parasympathetic action : a constricted gut with increased peristaltic activity (nausea, retching or vomiting)

45. Physiology effects of extradural block
The physiological effect of extradural blockade are similar to those following subarachnoid block.

46. Spinal anaesthesia：Indications
Lower extremities
Hip
Perineum
Lower abdomen
Lumber spine Type of surgery: Urology, Gynaecology, Obstetrics and any surgical procedure on the lower limbs or perineum.
Urologic endoscopic surgery, Rectal surgery, repair of hip fracture, obstetrics, orthopedic, Inguinal hernia repair, etc.

47. Spinal anaesthesia： Contraindications
Absolute: Sepsis Bacteremia Skin infection at injection site Hypovolemia Coagulopathy Therapeutic anticoagulation Demyelating central nerve system disease Increased intracranial pressure Psychosis or dementia Lack of consent

48. Spinal anaesthesia： Contraindications
Relative Peripheral neuropathy Mini-dose” heparin Aspirin or other antiplatelet drugs Prior lumbar spine surgery Chronic back pain Certain cardiac lesions Psychologic or emotional instability Uncooperative patients Prolonged surgery Surgery of uncertain duration Surgical team resistance to awake patients

49. Patient preparation Consent Physical examination Laboratory Tests
Premedication

50. Equipment & Safety General Preparation: Monitoring
Administration of GA if necessary
Resuscitation equipment
Regional equipment

51. Patient position
Sitting position
Lateral position
Prone position

52. Technique：Needle Technique
Midline Technique
Paramedian Technique

53. Factors influencing spinal anaesthesia
Agents: Procaine, Tetracaine, Lidocaine, Bupivacaine
Dosage
Vasoconstrictors
Specific Gravity: Hyperbaric technique, Hypobaric technique, Isobaric technique
Posture
Intra-abdominal Pressure
Spinal Curvature
Prior Surgery of Spine
Age
Obesity
Pregnancy
Spread of the agent
Redistribution

54. Spinal anaesthesia： Complications
Pain on injection
Backache
Headache
Urinary Retention
Meningitis and meningism
Vascular injury
Nerve injury: Cranial nerve palsy
High spinal anaesthesia
Transverse myelitis and cauda equina syndrome

55. Epidural anaesthesia ：Indications
Specific Indications Hip and knee surgery Low extremity Revascularization Obstetric deliveries Postoperative management

56. Epidural anaesthesia ： Contraindications
Epidural anaesthesia shares the contraindications discussed in the section on spinal anaesthesia.

57. Applied Physiology for Epidural Anaesthesia
Segmental Blockade
Differential Blockade

58. Table Agents for epidural anaesthesia
Agent Concentration Onset Sensory Block Motor Block
Chloroprocaine % Fast Analgesic Mild to moderate % Fast Dense Dense
lidocvaine ≥1% Intermediate Analgesic Minimal % Dense Mild to moderate % Intermediate Dense Dense
Mepivacaine % Intermediate Analgesic Minimal % Intermediate Dense Dense
Prilocaine % Fast Dense Minimal % Fast Dense Dense
Bupivacaine ≥0.25% Slow Analgesic Minimal % Slow Dense Mild to moderate
0.75% Slow Dense Moderate to dense

59. Technique of Epidural Anaesthesia
A) Safety
B) Preparation of the patient Informed consent Preoperative evaluation Laboratory assessment Premedication
C）Equipment: The epidural needle

60. Technical performance of a block
Identification of the epidural space:
Loss of resistance technique;
Hanging drop technique

61. Level selected
Lumbar epidural anaesthesia: Midline technique, paramedian technique
Thoracic epidural anaesthesia: Midline technique, paramedian technique
Cervical epidural anaesthesia: Midline technique

62. Strategies for injection of the anaesthetic agent
A test dose
Incremental dosing

63. Choice of local anaesthetic
Agent Concentration Onset Sensory Block Motor Block
Chloroprocaine % Fast Analgesic Mild to moderate % Fast Dense Dense
lidocvaine ≥1% Intermediate Analgesic Minimal % Dense Mild to moderate % Intermediate Dense Dense
Mepivacaine % Intermediate Analgesic Minimal % Intermediate Dense Dense
Prilocaine % Fast Dense Minimal % Fast Dense Dense
Bupivacaine ≥0.25% Slow Analgesic Minimal
% Slow Dense Mild to moderate
0.75% Slow Dense Moderate to dense

64. Factors that affect epidural anaesthesia
Dosage
Patient Age
Weight & Height
Posture
Vasoconstrictors
pH adjustment of local anaesthesia
Failure of epidural block

65. Epidural anaesthesia Complications(Intraoperative)
Dural tap
Total spinal anaesthesia
Profound hypotension
Apnoea
Massive extradural block and subdural block
Intravenous toxitity
Hypotension
Shivering
Nausea/ vomiting

66. Epidural anaesthesia Complications(Postoperative)
Headache
Infection
Extradural haematoma
Neurological complications

67. Caudal anaesthesia Indications
Obstetric patients, for vaginal deliveries
Surgery related to the sacral area (anorectal and vaginal procedures).

68. Caudal anaesthesia: Contraindications
The contraindications for caudal anaesthesia are the same as for any central block.

69. Caudal anaesthesia Complications
The complications of caudal block are essentially the same as those associated with epidural and spinal block.

70. Differences between subarachniod and extradural block
Subarachniod Extradural block
Small Large
Fast Slow
Complete anaesthesia Not complete anaesthesia
Cord transection Dermatomal
Dose of drug employed
Rate of onset
Intensity of block
Pattern of block

71. Peripheral nerve blocks
Upper limb blocks
Brachial plexus block
Axillary block
Supraclavicular block
Interscalene block

72. Peripheral nerve blocks
Lower limb blocks
Sciatic nerve block
Femoral nerve block
Mid tarsal block

73. Question What are the complication of local anaesthesia?
What are the features of local anaesthetic toxicity?
What are the absolute contraindications to subarachnoid block and extradural block?

74. Question
What are the major differences between subarachnoid block and extradural block?
How do you take the history from a patient?
What are the methods for identifying the epidural space?

75. Any Questions?
Thank you !