Dental Procedures
When a person with Duchenne undergoes general anesthesia, they are at risk for a number of serious problems.
Dental Procedure Recommendations
Dental hygiene and proper care are extremely important and help to reduce the incidence of oral and respiratory infections, specifically pneumonia. Dentistry generally can and should be performed with minimal or no anesthesia to provide the patient with maximal physical and emotional comfort. Local anesthetics (i.e. novocaine, lidocaine) or inhaled nitrous oxide (“laughing gas”) are both generally safe to use in people with Duchenne regardless of their pulmonary function or ambulation. Any oxygen use should be cautioned in people with Duchenne who are non-ambulatory and/or have abnormal pulmonary function.
Nitrous Oxide
The use of inhaled anesthetics (i.e. Halothane, Isoflurane, Seroflurane) can result in serious complications. One complication is rhabdomyolysis, which is the massive breakdown of skeletal muscle tissue which can ultimately damage the kidneys. Another is hyperkalemia, which is the release of too much potassium into the bloodstream which can result in cardiac arrest (“heart attack”).
Nitrous oxide (“laughing gas”), used during office dental procedures by an observant dentist, is an accepted and safe practice, even though it is inhaled. Nitrous oxide is a commonly used inhaled anesthetic in dentistry, emergency, and ambulatory centers. Advantages of nitrous oxide include:
- Impressive safety profile
- Provides excellent minimal and moderate sedation for anxious patients
- Quickly and easily absorbed into the bloodstream and the brain, as well as easily eliminated from the body
Following nitrous oxide, patients are generally given oxygen for 1-2 minutes in order to “wash out” the gas from the respiratory system. The oxygen is administered in an “open system” (mixed with room air), so the oxygen concentration is not 100%. The use of an “oxygen washout” is also a safe and appropriate practice for people with Duchenne.
Local Anesthetics
In many dental procedures, local anesthetics are often given via injection. Commonly used anesthetics include Novocaine or Lidocaine. Local anesthetics are considered safe for use in Duchenne.
Oxygen use
Many parents are concerned with the use of oxygen is mentioned. The use of oxygen in an ambulatory patient with normal lung function poses minimal threat. The use of oxygen by itself is a concern when its intended use is to treat hypoventilation in a non-ambulatory patient with decreased pulmonary function.
Patients with Duchenne who have pulmonary dysfunction (abnormal breathing) should consider receiving dental care requiring general anesthesia in a hospital or surgery center staffed with an anesthesiologist, and equipped to monitor intra-operative respiratory functioning and to manage potential respiratory and cardiac emergencies.
Non-ambulatory patients with Duchenne have weaker respiratory muscles. Therefore, as the disease progresses, it becomes difficult to cough and to take deep breaths. Up to a point, shallow breathing can provide the body with adequate oxygen supply and adequate removal of carbon dioxide. That delicate balance of oxygen and carbon dioxide allows breathing to continue. When extra or supplemental oxygen is given, this delicate balance is disturbed. The respiratory center may get the false impression that the body has enough oxygen, and the drive to breathe diminishes. Without effective breathing, carbon dioxide can build to dangerous levels (called hypercapnia).
Oxygen should never be given without constantly monitoring the level of carbon dioxide CO2 in the expired breath (the “end-tidal CO2”) or the CO2 level in blood. A normal end tidal CO2 is between 30-45 mmHg. A CO2 level (greater than 45 mmHg) indicates that CO2 is not being expelled from the body. Non-invasive ventilation (Bi-PAP via mouthpiece or nasal cannula) will assist with the mechanical process of breathing, delivery of oxygen and removal of CO2.
Dental Procedure Facts to Remember
- Dentistry generally can, and should, be performed with the minimal amount of anesthesia possible while providing the patient maximal physical and emotional comfort.
- Local anesthetics, nitrous oxide, and an oxygen “wash out” are safe for most patients with Duchenne, especially patients who are ambulatory with normal pulmonary function (normal breathing).
- Patients with Duchenne who have pulmonary dysfunction (abnormal breathing) should consider receiving dental care requiring general anesthesia in a hospital or surgery center staffed with an anesthesiologist, and equipped to monitor intra-operative respiratory functioning and to manage potential respiratory and cardiac emergencies.
Related Links
References
- Becker DE, Rosenberg M, “Nitrous Oxide and the Inhalations Anesthetics,” Anesth Prog, 2008, winter, 55(4): 124-131.
- “Respiratory Care of the Patient with Duchenne Muscular Dystrophy,” American Thoracic Society Document, Am J Respir Crit Care Med, 2004, 170: 456-465.
- Birnkrant D, Panitch HB, Benditt JO, Boitano LJ, Carter ER, Cwik VA, Finder JD, Iannaccone ST, Jacobson LE, Kohn GL, Motoyama EK, Moxley RT, Schroth MK, Sharma GD and Sussman MD, “American College of Chest Physicians Consensus Statement on the Respiratory and Related Management of Patients with Duchenne Muscular Dystrophy Undergoing Anesthesia or Sedation,” Chest, 2007, 132:1977-1986.
Acknowledgements
Pulmonologists(Dr. Jonathan Finder, Dr. Hemant Sawnani, and Dr. Richard Shell), dentistry (Dr. Elizabeth Vroom), and anesthesia (Dr. Norbert Weidner)