Hypoventilation, myoneural disorders, lung cancer, obesity, and its influence on driving

Home > Education and outreach > Road Safety Programs > Safe and healthy mobility > Clinical Topics and Safe Driving > Hematologic and Respiratory Diseases > Hypoventilation, myoneural disorders, lung cancer, obesity, and its influence on driving

Alveolar hypoventilation

Alveolar hypoventilation causes hypercapnia, that provokes respiratory acidosis and

hypoxemia, leading to a state of confusion with a distressing feeling of dullness, or even fainting.

Chronic hypoxemia can induce secondary polycythemia, pulmonary hypertension, and right heart failure.

Gas exchange worsens during sleep, causing morning headache, disorders in the quality of sleep, fatigue, daytime drowsiness and mental confusion.

The causes of alveolar hypoventilation include:

  • Defect in the metabolic control system of breathing for central nervous system diseases, abuse drugs, drugs, long-term hypoxia, etc.
  • Disorders in the neuromuscular system of breathing for spinal cord involvement in high cervical injuries, poliomyelitis, neuropathies, or involvement of respiratory muscles in myasthenia gravis, muscular dystrophy, chronic myopathy, etc.
  • Impairment of ventilation system due to a disorder in the chest wall for kyphoscoliosis, fibrothorax, thoracoplasty, ankylosing spondilytis and obesity.
  • Hypoventilation from airway and lung disease, COPD, cystic fibrosis, laryngeal and tracheal stenosis, and in obstructive sleep apnea.
  • The primary myoneural disorders cause gradually chronic hypoventilation, and these patients, in the event of respiratory overload due to a simple viral bronchitis, can suffer respiratory failure.

The weakness of the diaphragm is a frequent issue in orthopnea and paradoxical abdominal movement in supine position.

The treatment must be aimed at the underlying condition, and many patients improve with assistance through nocturnal or continued assisted ventilation.

Advice on Alveolar hypoventilation

  • These patients are highly susceptible and their limitations increase progressively preventing them from driving.
  • The physician will advise them against driving at the appropriate time of their disease progression.

Carcinoma of the lung

Carcinoma of the lung is only diagnosed in 5-15% when the patient does not show symptoms yet.

Smoking is seen in over 90% of male patients and in around 70% of female patients.

A small percentage of lung cancers are related to occupational agents, but always enhanced by smoking.

Central endobronchial tumors cause cough, hemoptysis, wheezing, stridor, dyspnea, and pneumonitis.

Peripheral lesions cause pain, cough, dyspnea, and possible symptoms of pulmonary abscess on cavitation.

Pulmonary and extrapulmonary dissemination cause multiple clinical problems that weaken and disable the patient progressively.

The treatment is based on reducing pain and anxiety with sedatives and opiates, treating infectious complications and breathlessness and eradicating the tumor with chemotherapy, radiation therapy, and surgery, if possible.

Advice on Carcinoma

  • Lung cancer, regardless of the symptoms, requires since its diagnosis cancer and/or surgical therapy, that, for their side effects and the disease itself, are disabling for driving.
  • Patients with a favorable progression and no symptoms of dyspnea, cough, pain, or general involvement, can always drive with favorable report from their physician in this regard.
  • The patient should be warned of the side effects of some analgesics and sedatives, that can interfere with driving, causing drowsiness and loss of attention and concentration.
  • All instrumental maneuvers or surgery in the chest required a more or less prolonged convalescence therapy without driving, that the patient must respect for the good outcome of the condition.
  • The recovery of the pulmonary capacity without sequels will permit driving, always with a favorable report from the physician.
  • The sequels of the pulmonary disease causing restriction of function, need a specialized study and report that indicates the actual handicap, to indicate for sure the capacity of this patient, already cured, to drive.


Obesity leads to mechanical overload of the respiratory tract.

Patients with morbid obesity can suffer hypercapnia, hypoxemia, and subsequently polycythemia, pulmonary hypertension and right heart failure.

Characteristics of the obese driver:

  • The position of the driver enhances the breathlessness of the obese patient.
  • Obese patients often adopt positions with the backing and the headrest not very adequate for driving.
  • The difficulty and inconvenience caused by the adjustment of the safety belt frequently lead them to disregard it, with a higher risk of serious disasters.
  • Obese drivers must separate their legs for the large volume of their thighs, leading to a poor support on the pedals and risk of accident.
  • Obese drivers have limited movements, which hinder maneuvers.
  • Obese drivers can tend to put their arm out of the window to increase the maneuverability of the other arm for driving.
  • Obese patients usually take food in the car and take it during traveling, with the risk of prolonged visual and physical diversion, for having one or both hands occupied to take the food.
  • Studies have shown that eating a hamburger is more distracting than talking by the mobile phone. The fashion of consuming fast food while driving not to waste time increases the number of accidents.
  • These drivers suffer more often drowsiness, aggravated by digestion.

Advice on Obesity leads

  • In addition to recommending them to lose weight to prevent the obesity disease, they should be recommended not to eat while they drive and, even if it is uncomfortable, to fasten their safety belt and adjust their neck-holder.
  • They should be recommended to make only small travels to relax their forced driving position and improve ventilation.
  • These patients are at a higher risk of deep venous thrombosis, so they should be recommended to make short trips when driving or many stops in long trips to walk and move their legs, and prevent possible PTE.