Lumbar Puncture

INTRODUCTION

• Lumbar puncture and analysis of cerebrospinal fluid is widely used as a diagnostic tool in neurological diseases.
• Lumbar puncture (LP) is the insertion of a needle into the subarachnoid space in the lumbar region to obtain cerebrospinal fluid (CSF) for diagnostic or therapeutic purposes.
• The CSF obtained by LP can provide crucial data in the diagnosis of life threatening conditions such as meningitis and encephalitis and evaluation of other disease conditions such as demyelinating diseases.
• Lumbar puncture is alsoperformed for therapeutic reasons, such as the treatment of benign intracranial hypertension. 
•  The spinal cord ends at the lower border of L1 vertebrae (Fig 1).
• Below this are nerve roots – the cauda equina. Lumbar puncture can be safely done below L1-2 vertebral space, as there is no risk of injuring the spinal cord.

Management of a difficult airway and failed intubation

Introduction

• Probably the most important job of an anaesthetist is to maintain a safe airway of an anaesthetised patient
• Difficulty in airway management is the single most important cause of anaesthesia related morbidity and mortality     
• If a difficult airway is detected and appropriate measures are taken to face it before anaesthetising a patient, morbidity and mortality associated with airway related problems can be minimised
• Hence the importance of assessing the airway during the pre-operative visit

What is a Difficult Airway?

• An airway which is difficult to be maintained or intubated or unable to be intubated in an anaesthetised or unconscious patient

IV Cannulation

Indications

1. Administration of IV fluids
2. Administration of blood products
3. Administration of IV therapy

Procedure

1. Confirm patient identity
   
2. Communicate with the patient
• Explain the procedure to the patient and get his/her verbal consent
• Try to minimize the patient distress
• Answer any questions the patient has
      
3. Gather the equipment needed
• Non sterile pair of gloves
• Kidney tray
• Tourniquet
• Sterile alcohol swabs
• IV Cannula of appropriate size

o Large bore cannulas are needed for rapid / thick fluid administration. E.g. 16 gauge gray canula

o The commonest used in day to day practice for IV fluid administration and drug administration are gauge 18 and 20

Anaphylaxis

Introduction-Anaphylactic reaction

· IgE -mediated type I hypersensitivity reaction.

· Effects are due to wide spread degranulation of mast cells.

· A dose independent unpredictable adverse drug reaction

 

Mechanism:

Commonly associated with a previous exposure to a similar group of drugs or chemicals. Foreign proteins act as antigens and stimulate production of IgEantibodies. They bind to mast cells and basophils, and with subsequent exposure massive degranulation occurs due to these already formed antibodies reacting with new antigens.

There is a massive release of mediators : Eg – Histamine, leukotrienes, tryptase, protease.

They give rise to bronchoconstriction, vasodilatation and increased capillary permeability. 

Malignant hyperthermia

Introduction.

• Inherited disorder in skeletal muscle cells
• Autosomal dominant
• Variable penetrance
• Incidence:-   1:15 000 – paediatrics         1: 40 000 – adult
• Can be lethal

Aetiology.

• A genetic mutation in Rynodine receptor, an intracellular calcium channel in sarcoplasmic reticulum.
• When triggered, there is an exaggerated release of calcium ions causing hypermetabolism.
• Triggering agents:- Halogenated inhalational anaesthetic agents Suxamethonium
• They can be otherwise healthy individuals.
• More susceptible in :-
• Duchenne muscular dystrophy
• Central core disease
• Osteogenesis imperfecta
• Strabismus surgery
• Repeated anaesthetics
• Positive family history.