Spinal Anaesthesia

August Bier 1885

SPINAL ANESTHESIA

ANAESTHETICS USED

HYPERBARIC (HEAVY)

LIGNOCAINE 5% IN 7.5%DEXTROSE

BUPIVACAINE 0.5% IN 5% DEXTROSE

HOW A HEAVY ANAESTHETICSOLUTION FLOWS IN CSF

INDICATIONS• Economical• Pulmonary Diseases• Full Stomach• Lower Abdominal Surgery• Ischemic Heart Diseases for Lower Abdominal Surgery

Fit patient requiring lower abdominal, anal of lower extremity surgery A patient having relative contraindication to general anaesthesia eg respiratory infection,

asthma, or a deformed airway

Operations where the patient needs to be placed prone eg excision pilonidal sinus

Operations of one lower extremity ( hemispinal)

CONTRAINDICATIONS

• Hypotensive Patients

• Cardiac failure

• Raised ICT

• Spinal Deformity

• Refusing Patients

• Bleeding Diathesis

• Skin Infection

CONTRAINDICATIONS

• Unco-operative patient

• Operations lasting more than 2 hours

• Hypovolemic shock

• Children

• Sepsis anywhere on the back

• Operations on the thorax and above

TECHNIQUE

• Preload with 500- 1000ml crystalloid

• Premedicate – pentazocine,prometazine, atropine

• Moniter BP,pulse and O2 sat, heart rhythm

COMPLICATIONS

IMMEDIATE

Hypotension- increase IV fluids, use small doses of vasoconstrictors eg mephenteramine ( 3mg iv as needed)

Bradycardia- iv atropine

Respiratory distress- supplement with O2, bag and mask or intubate

Inadequate block – supplement with IV ketamine

Total spinal

IV Isotonic Fluids

Vasopressors

Oxygen by mask

Pregnancy & Spinal

• Aortocaval Occlusion

• Pre loading with IV Fluids

• Left lateral Position• Vasopressors• Oxygen therapy

COMPLICATIONS

LATEHeadacheMeningitisBack pain

Local Anaesthetic Drugs

• Lignocaine 2%• Lignocaine 5%

• Bupivacaine 0 .5%

Lignocaine

• Dose 3mg /kg

• 7mg/kg with adrenaline

• Prolong action/reduces the toxicity

Lignocane Toxicity

• Tingling sensation around mouth

• Drowsiness

• Hypotension

• Fits

Treatment

• Dizepam/Thiopentone

• Muscle relaxant

Bupivacaine

• Longacting 4-6 hours

• Deferential blockers

-Sensory more than Motor

-Dose- 1-1.5 mg/kg

-Cardiac Toxic

-No Tachyphylaxis- Repeat drug

SPINAL CORD

Where Spinal Cord Ends

100% Sterile

Spinal Anaesthesia

Holding for Spinal

Sitting Position

Structures Pierced

Spinal Needle

Factors Influence The Level Of Anaesthesia

• The level of Injection

• The volume of drug• Tilt of Table• Speed of Injection

Advantages of spinal anaesthesia

• Full and complete anaesthesia• Prolonged block: Pain free postoperatively• Alternative to GA for certain poor risk patients esp.:- Difficult airway- Respiratory disease• Contracted bowel• Good muscle relaxation• Suitable for certain surgical procedures:-

Caesarian section (awake patient, bonding)

-Lower limb surgery

-Lower abdominal surgery

- Urological & gyneacological procedures.

SITTING / LYING

Reason For the Patho physiological Changes

• Blockade of the Sympathetic Systems

Cardivascular Changes

• Hypotension

• Tachycardia

• Bradycardia

• Sympathetic Blockade

• Marys law/Mayos Reflex

• Bainbridge Reflex

Drug for Spinal Anaesthesia

• Lignocaine• Bupivacaine

• Hyperbaric

Stay in the lowest area as per gravity

• 5% with Glucose• 0.5% with Glucose

• Does not mix up with CSF

How to prevent Delayed Complication

• Use Thin Spinal needles

• Sterile Precaution