Klippel-Feil Syndrome (KFS)

The airway is the headline - Fused cervical vertebrae with reduced flexion and extension make it impossible to align the oral, pharyngeal, and laryngeal axes for laryngoscopy. Assume both mask ventilation and intubation will be hard, and have the cart open in the room before induction: oral and nasopharyngeal airways, a full range of supraglottic airway sizes including one designed for intubation, fiberoptic bronchoscope, video laryngoscope, and a tracheostomy set.

Image the neck before you move it - Anteroposterior and lateral cervical radiographs in neutral, flexion, and extension show which segments are fused and rule out atlanto-occipital instability. CT demonstrates canal stenosis; MRI is the study when there is a deficit on exam. Document a baseline neurologic exam — cranial nerves, motor, sensory, reflexes, gait, and bowel or bladder symptoms — so any postoperative change has a comparator.

Fiberoptic first, awake when possible - Fiberoptic intubation avoids the flexion and extension that injures the cord, which is why it is the preferred technique. If the patient is developmentally able and cooperative, do it awake. If not, inhalational or IV induction with spontaneous ventilation preserved is the safer route; sevoflurane with oxygen insufflated at 10 L/min by nasal cannula through induction buys apnea time.

Limit laryngoscopy attempts - If direct laryngoscopy is used, the most experienced laryngoscopist takes it and it stops at one or two attempts. Move to video laryngoscopy, flexible bronchoscopic intubation, or fiberoptic through a supraglottic airway early rather than after several failures. Video laryngoscopy gives a glottic view without axis alignment, which is exactly the forceful neck movement you are trying to avoid.

Don't paralyze before you can ventilate - Video laryngoscopy works best with relaxation, but where the ability to ventilate is in doubt, the relaxant waits until the airway is secured. In the published cases the relaxant was given after the tube was in and position confirmed.

Supraglottic devices press on the neck - An LMA is a legitimate rescue and an intubating LMA is a route to the tube, but supraglottic devices exert measurable pressure against the cervical vertebrae, which is hazardous with an unstable spine. Manual in-line stabilization stays on throughout airway management.

Have smaller tubes ready - A short, restricted neck produces venous and lymphatic congestion of the airway. Edematous cords and arytenoids with a smaller-than-expected tracheal dimension are reported findings; 6.5 mm cuffed tubes were used in adult women in the published series. Pull the sizes below your first choice before you start.

Plan the surgical airway out loud - Keep surgical help on standby for emergency tracheostomy in a cannot-ventilate, cannot-oxygenate situation, and brief the room on who cuts before induction.

Neuraxial is unpredictable, not off-limits - Around 60% have scoliosis, which makes the block technically hard and the spread of local anesthetic unpredictable; complete failure after a textbook single-attempt subarachnoid block is documented, as is patchy epidural spread. Fused segments concentrate motion on unfused ones, raising the risk of neuraxial injury from mild trauma. Use it when the interspaces are palpable, but keep the airway cart set up for conversion the entire time.

Cardiac and renal anomalies - Ventricular septal defect is the most common cardiac lesion; get an echocardiogram if there is a murmur on the preop exam. Renal anomalies — ectopia, hydronephrosis, horseshoe kidney, absent kidney — are reported in 30% to 64% of patients, so check a creatinine and dose renally cleared drugs to it. Renal ultrasound is the screening study.

Positioning and pulmonary reserve - Scoliosis and chest wall deformity make positioning awkward and can restrict respiratory and cardiovascular mechanics enough to require postoperative cardiorespiratory support. Settle the PACU or ICU disposition before the case, not at extubation.

Extubate fully awake - Given how hard reintubation would be, the bar is awake, following commands, and taking adequate tidal volumes. That is what the reported cases did.

Sudden neck movement - Syncopal attacks can be precipitated by abrupt neck movement. Move the head deliberately at every transfer, including onto the PACU bed.

Glycopyrrolate for secretions - Where a fiberoptic technique is planned, an antisialagogue before induction keeps the view; 0.2 mg IV given 15 minutes before induction is the documented approach in this population.

Klippel-Feil syndrome (KFS) is congenital fusion of two or more cervical vertebrae, caused by failed segmentation of the cervical somites in weeks 3 to 8 of gestation. Incidence is about 1 in 42,000 births with a slight female predominance; most cases are sporadic, though GDF6 and GDF3 (autosomal dominant) and MEOX1 (autosomal recessive) mutations are described.

The classic triad of short neck, low posterior hairline, and severely restricted neck motion is present in fewer than half of patients, so KFS is easy to miss until you try to intubate. C2-C3 and C5-C6 are the interspaces most often fused. Fused segments throw extra motion onto adjacent levels, roughly half have atlantoaxial instability, and congenital canal stenosis means a low-energy insult can produce a real neurologic deficit.