Many patients are predisposed to respiratory problems in the dental setting; these patients include patients with asthma or chronic obstructive pulmonary disease (CO PO), extremely anxious patients, patients who are. atopic, and those in whom a noninhalation sedative technique using respiratory depressant drugs is to be used. Special precautions should be taken to help prevent the occurrence of emergencies. If these patients are not treated promptly, • the situation may become life threatening.
Asthma. Patients with a history of asthma can be a particular challenge to safely manage if emotional stress or many pharmacologic agents easily. trigger their respiratory problems. Most patients with asthma are aware of
the symptoms that signal the onset of bronchospasm. Patients will complain of shortness o( breath and want tosit erect. Wheezing is usually audible; tachypnea and tachycardia begin,and patients start using their accessory muscles of respiration. As bronchospasm progresses,
patients may become hypoxic and cyanotic, with eventual loss of consciousness (Box 2-6).
Management should start with placing patients in an erect or semierect position. Patients should then administer brortchodilators, using their own inhalers or one provided from the office emergency supply. The inhaler may contain epinephrine, isoproterenol, metaproterenol, or albuterol. Repeated doses should be administered caused
Manifestations of an Acute Asthmatic Episode
Mild to Moderate
• Wheezing (audible with or without stethoscope)
• Dyspnea (i.e., labored breathing)
• Intense dyspnea, with flaring of nostrils and use of
accessory muscles of respiration
• Cyanosis of mucous membranes and nail beds
• Minimal breath sounds on auscultation
• Flushing of face
• Extreme anxiety
• Mental confusion
Hyperventilation. The most frequent cause of respiratory difficulty in the dental setting is anxiety that is expressed as hyperventilation, which is usually seen in patients in their teens, 20s, and 30s, and can frequently
be prevented through anxiety control. Dentists should be attuned to the signs of patient apprehension and, through the health interview, should encourage patients to express their concerns. Patients with extreme anxiety should be managed with an anxiety reduction protocol. In addition, pharmacologic anxiolysis may be necessary. The first manifestation of hyperventilation syndrome is frequently a complaint of an inability to get enough air. They breathe very rapidly (tachypnea) and become agitated. The rapid ventilation increases elimination of CO2
through the lungs The patient rapidly becomes alkalotic; may complain of becoming lightheaded and of having a tingling sensation in the fingers, toes, and perioral region; and may even develop muscle twitches or convulsions.
Eventually loss of consciousness occurs (Box 2-7).
Management of a hyperventilating patient involves terminating the surgical procedure, positioning the patrent in a semierect position, and providing reassurance.If symptoms of alkalosis occur, the patient should be forced
to breathe into and out of a small bag (Fig. 2-5). Oxygenenriched air is not indicated. If hyperventilation continues, the clinician may have to administer a sedative such as rnidazolam, DY giving 2 to 4 mg 1Mor by IV titration of the drug until hyperventilation ceases or the patient is
sedated. Once hyperventilation stops, the patient should be rescheduled, with plans to use preoperative or intraoperative sedation (or ‘both) in future visits (Box 2-8).
with. well-compensated COPD can have difficulty during oral surgery. Many of these patients depend on maintaining an upright posture to breathe adequately. In addition, they become accustomed to having high arterial .
CO2 levels and use a low level of blood oxygen as the primary stimulus to drive respirations. Many of these patients experience difficulty if placed in an almost supine position or if placed on high-flow nasal oxygen. Patients with COPD often ·rely on their accessory muscles of respiration to breathe. Lying supine interferes with the use of these accessory muscles; therefore patients will usually ask to sit up before problems resulting from positioning occur. Excessive lung secretions that are more difficult
to clear when supine also accompany COPD.
If .excessive oxygen is administered to a patient susceptible
to COPD, the respiratory rate will fall, which pro-
Manifestations of Hyperventilation Syndrome
duces cyanosis, and apnea may eventually occur. The treatment for such a problem is to discontinue oxygen administration before the patient becomes apneic. The respiratory rate should soon improve. If apnea occurs and the patient loses consciousness, artificial ventilation must
be initiated ‘and emergency assistance summoned.
Foreign-hody aspiration. Aspiration of foreign bodies into the airway is always a potential problem during oral surgical and other dental procedures. This is especially true if the .patient is positioned supine or semierect in the chair or is sufficiently sedated to dull the gag reflex. Objects that fall into the hypopharynx are frequently swallowed and usually pass harmlessly through the gastrointestinal tract. Even if the clinician’ feels’ confident the material was swallowed, chest and
abdomina.l radiographs should be obtained to eliminate the possibility of asymptomatic aspiration into the respiratory tract. Occasionally the foreign object is aspirated into the larynx, where, in the lightly sedated or
nonsedated patient, violent coughing will ensue that may expel the aspirated material. The patient can usually still talk and breathe. However, larger objects that are aspirated may obstruct the airway and become lodged in such a manner that coughing is ineffective because the
‘lungs cannot be filled with air before the attempted cough. Inthis situation the patient usually cannot produce any vocalizations and becomes extremely anxious. Cyanosis soon appears, followed by loss of consciousness (Box 2-9).
The manner in which aspirated foreign bodies are ma. ;;ed depends primarily on the degree of airway obstruction. Patients with an intact ga reflex and a partially obstructed airway should be allo ed to attempt to
expel the foreign bodY by coughing. If the material will not come up, the patient should be given supplemental oxygen arid transported to an emergency facility to allow laryngoscopy or bronchoscopy to be performed. The completely obstructed but awake patient should have abdominal thrusts ·(Fig. 2-6, A) or Heimlich maneuvers
(Fig. 2-6, B) performed until successful or consciousness is lost. If a patient has a dimiriished gag reflex as a result of
Management of Hyperventilation Syndrome
1. Terminate all dental treatment and remove foreign
bodies from mouth.
2. Position patient in chair in almost fully upright
3. Attempt to verbally calm patient.
4. Have patient breathe CO2-enriched air, such as in
and out of a small bag.
5. If symptoms persist or.~orsen, administer diazepam.
10 mg 1Mor titrate slowly IVuntil anxiety isrelieved,
or administer midazolam 5 mg 1Mor titrate slowly IV
uritil anxiety is relieved.
6. Monitor vital signs.
7.. Perform all.further dental surgery using anxietyreducing
1M, Intramuscular; III, intravenous .
He. 2-6 A, t\ lethod of f1crfc,~;nmg abdominal thrusts for an unconscious patient with foreign body obstructing airway. Chair is first placed in recumbent position. The heel of the dentist’s right palm is placed on the abdomen just below the xiphoid process, with the elbow Kept locked and the left hand placed over the right for further delivery of force. Arms are quickly thrust into ‘the patient’s abdomen, directing force down and superiorly. 8, Proper positioning for Heimlich maneuver is shown. Rescuerapproaches the patient from behind and positions hands on the patient’s abdomen, just below the rib cage. Rescuer’shands are then quickly pulled into the abdominal area, attempting to have any residual air in the lungs dislodge the obstruction from airway.
Acute Manifestations of Aspiration into the Lower Respiratory Tract
Large Foreign Body Gastric Contents • Coughing • Coughing • Choking sensation • Stridcrousbreathlnq • Stridorous breathing • Wheezing or rales
(l.e., crowing sounds) (i.e., cracking sound) • Severe dyspnea on chest auscultation
• Feeling of something • Tachycardia
caught.in throat • Hypotension .
• Inability to breathe • Dyspnea • Cyanosis • Cyanosis
• Loss of consciousness
sedation or has a completely obstructed airway and loses consciousness, abdominal thrusts should be performed with the patient in a supine position. After each volley of thrusts, the patient should be quickly turned onto the side and the clinician should finger sweep the mouth to remove any Object that may have been forced out. Ifthe patient is not exchanging air, BLS should be started. If air cannot be blown into the lungs., additional abdominal thrusts should be attempted, followed by oral finger sweeps and BLS. Dentists trained-in laryngoscopy can look into the larynx and use Magill forceps to try to remove any foreign material. If several attempts to relieve the obstruction fail, an emergency cricothyrotomy may be necessary (Fig. 2-7) .
contents into the lower respiratory tract presents another situation that frequently leads to serious respiratory difficulties. The particulate matter in gastric contents causes physical obstruction of pulmonary airways, but it is usually the high acidity of gastric material that produces more serious problems. The low pH of gastric juice quickly necrotizes the pulmonary tissue it contacts, and a respiratory distress syndrome soon follows, with transudation of fluid into pulmonary alveoli and a loss of functioning lung tissue. The patient with an intact gag reflex rarely aspirates gastric contents during vomiting. Rather it is the patient with a diminished gag reflex
caused by sedatiori, unconsciousness, or topical anesthesia in the oropharynx who is at greatest risk ‘for gastric aspiration. The sedated or unconscious patient who aspirates a signiflcant amount of gastric material will first show signs of respiratory difficulty, ‘such as tachypnea
and wheezing. Tachycardia and hypotension may soon occur and, as ventilatory capability worsens, cyanosis appears. Eventually respiratory failure occurs that is refractory to BLS and requires both intubation and the
delivery of high concentrations of oxygen.
Prevention of gastric aspiration involves instruction to patients to avoid eating or drinking for I) hours before any oral surgery appointment during which they are to be moderately or deeply sedated.
A deeply sedated or unconscious patient who begins to vomit should be immediately placed into a head-down, feet-raised position and turned onto the right side to encourage oral drainage of vomitus, Box 2-10 lists several
symptoms exhibited by patients preparing to vomi t. High-volume suction should be used to assist removal of vomitus from the oral cavity, If the clinician suspects that gastric material may have entered the lower respiratorv tract, a call should be placed for emergency assistance.
The patient should be placed on supplemental oxygen and vital signs monitored, If possible, the dentist should gain venous access (i.e., start an IV) and be prepared to administer crystalloid solution (e.g. normal saline or OsW) to help treat a falling blood pressure and allow emergency technicians to administer IV bronchodilators if necessary. Immediate transportation to an emergency facility is mandatory (Fig, 2-8).