Makindo Medical Notes.com

Related Subjects: Atropine |Acute Anaphylaxis |Basic Life Support |Advanced Life Support |Adrenaline/Epinephrine |Acute Hypotension |Cardiogenic shock |Distributive Shock |Hypovolaemic or Haemorrhagic Shock |Obstructive Shock |Septic Shock and Sepsis |Shock (General Assessment) |Toxic Shock Syndrome

Introduction

• Ensure you have had formalised training in this before attempting. Ensure that it is needed. I have seen time wasted with central cannulation to do something when other things more pressing. A patient with peripheral access and a GI bleed dying of haemorrhagic shock needs endoscopy/surgery and will not be saved by a central line. Central lines have significant complications. Always document why you are doing it. Is it really needed? Indications that you need to justify. Predictors of poor outcome are emergency placement, Obesity, coagulopathy, intubation, hypotensive. Always be ready to phone a friend if things are not going well and plan this in advance
  • IV access
  • Infusion of irritant substances
  • CVP monitoring
  • Advanced haemodynamic monitoring (PICCO, PA catheter)
  • Central venous oxygenation monitoring
  • Cardiac pacing
  • Inadequate peripheral access
  • Extracorporeal therapies (ECMO, CRRT)
  • IVC filter placement
  • Venous stenting
  • Catheter-guided thrombolysis
• Consider Contraindications
  • Lack of consent - needs special consent form if patient lacks capacity
  • Inexperience, unsupervised operator
  • Obstructed vein (eg. clot) or Distorted local anatomy
  • Stenosis of the vein
  • Raised ICP (IJ line)
  • Severe coagulopathy
  • Respiratory failure with high FiO₂ risk of PTX
  • Contaminated site
  • Traumatised site (eg. clavicle fracture and subclavian line)
  • Burned site or large neck mass or previous radiation damage
  • Uncooperative awake patient
  • Patient cannot lie flat e.g. Pulmonary oedema !!!
  • Patient coughing , agitated
  • No absolute contraindications
• Ensure you have the correct equipment and a USS probe. How to tell carotid artery from the jugular vein
  • Artery circular, vein elliptical
  • Artery smaller, vein bigger
  • Artery pulsatile, vein less so unless severe TR
  • Artery non compressible, vein compressible
  • Artery thicker wall
  • Valsalva vein dilates
  • Artery shows pulsatile flow on doppler
• The vein originates at the jugular foramen and runs down the neck, to terminate behind the sternoclavicular joint, where it joins the subclavian vein. It lies alongside the carotid artery and vagus nerve within the carotid sheath.
• The vein is initially posterior to, then lateral and then anterolateral to the carotid artery during its descent in the neck. The vein lies most superficially in the upper part of the neck.
• Positioning is key: Place the patient in a supine position, at least 15 degrees head-down to distend the neck veins and to reduce the risk of air embolism. It maximises IJV visibility. Turn the head away from the venepuncture site. This stretches the vein and keeps it from moving. Cleanse the skin and drape the area. Sterile gloves and a gown should be worn (see catheter-related sepsis).
• Localise using either Ultrasound-guided technique or landmark technique using Seldinger Landmark technique. If the patient is awake, use a local anaesthetic to numb the venepuncture site. Introduce the large calibre needle, attached to an empty 10 ml syringe, into the centre of the triangle formed by the two lower heads of the sternocleidomastoid muscle and the clavicle.
• Palpate the carotid artery and ensure that the needle enters the skin lateral to the artery. Direct the needle caudally, parallel to the sagittal plane, at a 30-degree posterior angle with the frontal plane, aiming towards the ipsilateral nipple.
• Once blood is aspirated, cannulate the vein using the Seldinger technique. The catheter tip should lie in the superior vena cava above the pericardial reflection. Perform a check chest X-ray to confirm the position and exclude pneumothorax.
• Complications
  • Pneumothorax/haemothorax - a high approach that minimises this risk.
  • Air embolism - ensure head-down position.
  • Arrhythmias - avoid passing guidewire too far, observe rhythm on the cardiac monitor during insertion.
  • Carotid artery puncture/cannulation - palpate artery and ensure the needle is lateral to it, use ultrasound-guided placement, transduce needle before dilating and passing central line into the vessel, or remove the syringe from needle and ensure blood is venous.
  • Chylothorax - use a high approach and avoid the left side wherever possible.
  • Infection - see section on catheter-related sepsis.

Anatomy and Technique

References

• Also see here the NEJM paper here