CORRESPONDENCE – Suggested changes in central venous cannulation

Nouman I. Alvi, FCARCSI and Dileep Kumar, FCPS

Department of Anaesthesia, Aga Khan University, Karachi (Pakistan); E-mail:

Use of ultrasound (US) is standard of care these days for central venous access[1]. Traditionally, a 22 or 25 gauge seeker needle (injection) was used to locate the internal jugular vein. After the introduction of US in clinical practice introducer needles are now used alone for localization and threading guide wires into central veins. In our University-hospital based Department, Arrow®triple lumen catheter sets are being used, containing an 18G 2.5″ (6.35 cm) needle as introducer. Approximately two thousand central lines are placed under US annually and our faculty has largely discarded the practice of using seeker needles. The depth and coordinates3,4 of internal jugular vein are estimated by using the calibrated view on the display screen of the ultrasound machine.

We feel that there ought to be two changes in the introducer needles; graduated markings on the shaft and a reduced length (up to 3.5 cm). They are usually 6.35 cm to 8 cm long depending on commercial makes.  This length is hardly ever needed even in obese patients Figure 1. These changes will prompt   anesthetists to gauge the required depth and the introducer needle would be inserted according   to calculated depth. These changes will preclude the risks of pneumothorax, brachial plexus, spinal cord and thoracic duct injuries which are known complications2 of central vein cannulation using a traditional long, unmarked introducer needle.


Figure 1: Introducer needles with suggested graduated markings


  1. Guidance on the use of ultrasound locating devices for placing central venous catheters, National Institute for Clinical Excellence, ISBN: 1-84257-213-X, 04 October 2002
  2. Chapman GA,  Johnson D, Bodenham AR. Visualisation of needle position using ultrasonography. Anaesthesia 2006 Feb;61(2):148-58
  3. Dietz HP, Haylen BT, Broome J. Ultrasound in the quantification of female pelvic organ prolapse. Ultrasound Obstet Gynecol. 2001 Nov;18(5):511-4.
  4. Kirchmair, Lukas, Entner, Tanja MD; Kapral, Stephan MD; Mitterschiffthaler, Gottfried MD. Ultrasound Guidance for the Psoas Compartment Block: An Imaging Study.Anesth & Analg  2002 March;94(3);706-710