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 ANAESTHETIC SOLUTION 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 LATE Headache Meningitis Back 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