Kyphoscoliosis

Grade the restriction with numbers - PFTs show a reduced FRC, FVC, and FEV1, but the 6-minute walk test correlates with severity of deformity better than pulmonary function testing or arterial blood gases do. Ask for both, and note that increasing Cobb angle tracks with worse PFTs.

Look for right heart strain - Echocardiogram is the screening study for pulmonary arterial pressures and RV size and function, with TAPSE quantifying RV systolic performance; right heart catheterization confirms pulmonary hypertension at a mean PA pressure of 25 mmHg or more with a normal wedge. Once cor pulmonale is established the prognosis is poor and mortality rises.

Oxygen is a pulmonary vasodilator - Hypoxia is the trigger for hypoxic pulmonary vasoconstriction, and relieving hypoxemia improves cardiac output, lessens sympathetic vasoconstriction, and improves renal perfusion. Treat desaturation as a right-heart problem, not just a saturation number.

Small FRC, short apnea time - The oxygen reservoir these patients induce with is reduced, so denitrogenate deliberately and have the airway plan and a second operator ready before you give the relaxant.

Stiff chest wall, careful ventilation - Reduced distensibility means higher airway pressures for smaller tidal volumes. Watch peak and plateau pressures rather than chasing a textbook tidal volume.

RV failure rescue - A plain vasoconstrictor is a limited tool because raising systemic vascular resistance can raise pulmonary vascular resistance too. Inhaled iloprost or IV milrinone combined with sildenafil lowers PVR without dropping systemic pressure, and low-dose vasopressin raises SVR while lowering PVR through nitric oxide release from the pulmonary endothelium.

Neuraxial is unpredictable - Rotation and two-plane deviation make spinous processes hard to palpate, and poor palpability plus anatomic deformity is associated with block failure and inadequate spread. Blocks may be patchy, unilateral, or fail outright. Check sensory level by pinprick or cold and motor block by modified Bromage within 10 minutes, and keep a full general anesthetic ready. Reattempting carries the risk of a high spinal; siting an epidural one level above the attempt is the better alternative.

Instrumented spines close doors - Arthrodesis with rods, wires, and screws removes the fused segments from neuraxial access, and fusion alters mechanical forces so the unfused segments become excessively mobile and vulnerable to injury from even mild trauma.

Sensitive to everything given - This population tolerates perioperative medication and its side effects poorly because of functional limitation and prolonged immobilization. Titrate sedatives, opioids, and neuromuscular blockers to effect, confirm full reversal with TOF, and sit them up early.

Plan the postoperative bed - Severe deformity affects both respiratory and cardiovascular mechanics and may require postoperative cardiorespiratory support. Decide on a monitored or step-down bed at booking, not in PACU.

Position around the deformity - Padding and support have to be built for the actual spine in front of you; standard table contours will not match it, and these patients carry a documented risk of pressure sores.

Pregnancy raises the stakes - Restrictive lung disease is rare in pregnancy, and when it appears it is usually from neuromuscular disease or kyphoscoliosis. Involve obstetric anesthesia early rather than meeting the anatomy on labor and delivery.

Kyphoscoliosis is deviation of the spine in both the sagittal and coronal planes, usually with rotation of the spinal axis, most often thoracolumbar. The added kyphotic component is what separates it from scoliosis alone — see the Scoliosis entry for curve measurement and surgical thresholds. Collapsing the chest front-to-back as well as laterally deforms the rib cage and makes this a classic extrapulmonary cause of restrictive lung disease: chest expansion turns asymmetric, inspiratory capacity falls, and FRC, FVC, and FEV1 all drop.

Chronic hypoxemia then drives sustained hypoxic pulmonary vasoconstriction and smooth-muscle proliferation in the small pulmonary arteries. Pulmonary vascular resistance climbs, right ventricular work rises, and the RV hypertrophies and dilates into cor pulmonale. Kyphoscoliosis complicated by pulmonary hypertension carries high mortality.