A Case for Bleeding: Structures at the
Risk of Injury during Invasive Procedures
of the Cricothyroid Membrane
Ivan James Prithishkumar
Department of Anatomy
Christian Medical College
Vellore - 632002, India.
Phone: +91 416 2284245
Fax: +91 416 2262788
Background: Transcutaneous puncture of the cricothyroid membrane is a component of several important invasive clinical procedures, including surgical cricothyroidotomy. One of its most feared complications is endolaryngeal haemorrhage that has been fatal at times.
Aim: Our aim was to determine the structures at the risk of injury during procedures which involved puncture of the cricothyroid membrane.
Methods: Anterior neck dissection was done on sixty three cadavers in a tertiary care, university teaching hospital. Results: Several structures were noted to be anterior to the membrane, such as the paired and the median anterior jugular veins, the transverse cricothyroid artery, the median descending artery, the sternohyoid muscle, the pyramidal lobe of the thyroid gland, the thyroidea ima artery and the jugular venous arch. The transverse cricothyroid artery was seen anterior to the upper 1/4th of the membrane in 98% of the cadavers. In most of the cadavers, the right and left transverse cricothyroid arteries joined to form a median descending artery. Both the transverse cricothyroid artery and the median descending artery gave multiple branches that perforated the cricothyroid membrane.
Conclusion: All invasive procedures require a firm grounding in anatomy. Regarding surgical cricothyroidotomy, the authors recommend an initial vertical incision of the skin and the investing layer of the deep cervical fascia, followed by a horizontal incision of the cricothyroid membrane, just above the arch of the cricoids, to avoid the transverse cricothyroid artery. For needle procedures, the authors suggest an anterior midline approach, immediately above the arch of the cricoid.