Measures appropriate for specific causes of ALF are described in detail later in this chapter. Neurologic complications
Patients with grade I–II encephalopathy should be transferred to a liver transplant facility and listed for transplantation. Consider a brain computed tomography (CT) scan to rule out other causes of altered or impaired mental status. Stimulation and overhydration can cause elevations in intracranial pressure (ICP) and should be avoided. Unmanageable agitation may be treated with short-acting benzodiazepines in small doses. Lactulose can be considered at this stage. A preliminary report from the ALFSG on 117 patients suggests that use of lactulose in the first 7 days after diagnosis is associated with a small increase in survival time, but with no difference in severity of encephalopathy or in the overall outcome. For patients who progress to grade III–IV encephalopathy, intubation for airway protection is generally required. Many centers use propofol for sedation because it may reduce cerebral blood. The head of the bed should be elevated to 30 degrees, and electrolytes, blood gasses, glucose, and neurologic status monitored frequently. Cardiovascular complications
Increased cardiac output and low systemic vascular resistance are characteristic of ALF. Pulmonary artery catheterization should be considered. Hypotension should be treated preferentially with fluids, but systemic vasopressor support with agents such as epinephrine, norepinephrine, or dopamine should be used if fluid replacement fails to maintain mean arterial pressure of 50–60 mm Hg. Vasoconstrictive agents (especially vasopressin) should be avoided. Pulmonary complications
Pulmonary edema and pulmonary infections are commonly seen in patients with ALF. Mechanical ventilation may be required.
There is limited data on hormone treatment and tranexamic acid to reduce bleeding and anemia. Severe anemia or episodes of severe bleeding are treated with endoscopic argon plasma coagulation (APC) or laser treatment of any lesions identified; this may reduce the need for supportive treatment. The expected benefits are not such that repeated attempts at treating lesions are advocated. Sudden, very severe bleeding is unusual—if encountered, alternative causes (such as a peptic ulcer) need to be considered—but embolization may be used in such instances. Lung AVMs
Lung lesions, once identified, are usually treated to prevent episodes of bleeding and more importantly embolism to the brain. This is particularly done in lesions with a feeding blood vessel of 3 mm or larger, as these are the most likely to cause long-term complications unless treated. The most effective current therapy is embolization with detachable metal coils or plugs. The procedure involves puncture of a large vein (usually under a general anesthetic), followed by advancing of a catheter through the right ventricle and into the pulmonary artery, after which radiocontrast is injected to visualize the AVMs (pulmonary angiography). Once the lesion has been identified, coils are deployed that obstruct the blood flow and allow the lesion to regress. In experienced hands, the procedure tends to be very effective and with limited side effects, but lesions may recur and further attempts may be required. CTA scans are repeated to monitor for recurrence.