Neurological disorders due to renal failure and liver disease, and their influence on driving
Urea increases can cause malaise, anorexia, laxity, fatigue, vomiting, and reduction of the mental sharpness.
Chronic renal failure affect cellular function and metabolism, as well as the volume and composition of body fluids occurring with polyuria and nycturia in the phases of mild or moderate renal failure.
Neurological disorders are frequent, with paresthesia due to polyneuropathy of distal, bilateral, and symmetrical distribution, night sensation of burning and restlessness in the legs and muscle cramps.
The signs of encephalopathy join variably the confusion, alertness disorders, convulsive crises and abnormal movements with agitating tremor myoclonus.
Psychological disorders occur, including depression, irritability, and risk of suicide.
In advanced cases uremic encephalopathy starts, with asterixis, seizures, and coma.
The dialysis improving renal failure can cause dementia and “imbalance;” and on the other hand, from simple nausea to seizures.
Several drugs, particularly antibiotics, can trigger in these patient signs of severe encephalopathy with seizures.
Advice on renal failure
- Patients with slightly decreased renal reserve do not show symptoms, and can drive.
- Mild to moderate renal failure can show only vague symptoms such as nycturia not interfering with driving, except for the tiredness caused by the absence of the adequate night rest.
- The first manifestations of uremia such as laxity, fatigue, and reduced mental sharpness reduce the capacity for conduction, so the patient must not drive until the specialist, through the appropriate treatment and subsequent favorable evolution of the patient, decides that he can drive safely.
- Neuromuscular manifestations such as sharp muscle contractions, peripheral neuropathies with sensitive and motor manifestations, muscle spasms and seizures preventing from driving.
- It is recommended not to drive in case of episodes of ulcers with digestive bleeding and risk of new bleeding, occurring with the advanced disease.
- The patient with stable chronic renal failure and few symptoms can suffer acute decompensation with a concomitant disease, and suddenly worsen. He must not drive until he is stabilized and without symptoms.
- The patient with diabetic nephropathy not adjusting the dose of insulin to the progression of renal failure can suffer serious episodes of hypoglycemia appearing while driving, that could eventually lead to losing the control of the car.
- Physicians should warn to all driving patients with renal failure that many drugs can cause them side effects that will interfere with driving, if the dosage is not adjusted.
- It is the case of anxiolytics, antidepressants, anticonvulsants, etc., where the adverse reactions should be known by the patient.
- The driver with uncontrolled psychological and depressive disorders should be advised against driving until the favorable outcome of his condition is verified.
- The hemodialysis session is disabling for driving for the possible and frequent side effects that the patients show at the end of it.
- The safety of driving on the intermediate days among the dialysis sessions of dialysis depends on the symptoms shown by the patient, both the characteristic of renal failure and of the causal disease.
- In general these are susceptible patients due to the advanced renal failure so they are recommended to run the lowest risks, and one of the possible risks would include driving.
It is relatively frequent in some liver diseases such as cirrhosis.
Encephalopathy of cirrhosis frequently has a triggering factor such as the digestive bleeding, some drugs such as barbiturates, morphine, benzodiazepines, acetazolamide, etc.
Liver encephalopathy is characterized by disorders of the central nervous system, with reduced consciousness, from somnolence and confusion to stupor and coma.
The inversion of sleep rhythm, intellectual disorders with bradypsychia, inability to maintain attention, temporospatial disorientation are frequent
Also, personality disorders including euphoria, depression, aggressiveness, and behavior disorders.
Often neuromuscular disorders occur, including asterixis, hypertonia, seizures, tremor, ataxia, amimia, choreoathetosis, spastic paraplegia, etc.
The treatment of these patients is complex and multidisciplinary and requires expert physicians to avoid any complication.
Liver transplant has returned life to many of these patients.
Advice on liver encephalopathy
- Patients with mild or moderate liver insufficiency only with symptoms of dyspepsia can drive.
- If the underlying disease is chronic and progressive, at some time of the evolution the patient will start to suffer neurological disorder, loss of care and somnolence, that will disable him for driving.
- The physician must advise the patient against driving when the clinical manifestations reduce the safety on driving, and report it in writing.
- Liver transplant has returned life and makes that a great number of these patients can drive again, when the physician considers it adequate through a written report.