key: cord-0060769-9vl8tp73 authors: Tomsic, Jaclyn A.; Ashrafi, Alireza; English, Ray; Brown, Kiara title: Respiratory Diseases date: 2020-05-11 journal: Oral Board Review for Oral and Maxillofacial Surgery DOI: 10.1007/978-3-030-48880-2_14 sha: 968280320dda6d7a02d280a31248b5d19ff186e7 doc_id: 60769 cord_uid: 9vl8tp73 Asthma: Chronic obstructive disease with bronchiolar inflammation and hyperresponsiveness that displays reversible, variable, and recurrent airway obstruction. • Total lung capacity (TLC) is the total volume of air that can be contained in the lung. • Functional residual capacity (FRC) is the volume of air in the lungs after normal exhalation. • Expiratory reserve volume (ERV) is the volume of air that can still be expired after normal exhalation. • Inspirational reserve capacity (IRC) is the maximum volume of air that can be inspired at the end of normal inspiration. • Forced vital capacity (FVC) is the maximum volume of air that can be exhaled. • Residual volume (RV) is the volume of air remaining in the lungs at the end of forced exhalation. • Inspiratory capacity (IC) is the maximum volume of air that can be inspired. • Tidal volume (VT) is the volume of air during normal inspiration. • Vital capacity (VC) is the total volume of air that can be expired after maximum inhalation. • Forced expiratory volume (FEV1) is air that can be expired in 1 second. • FEV1/FVC ratio represents the proportion of vital capacity that is expired in the first second of forced expiration. Normal value is 80%. • FRC serves as a reservoir of oxygen. FRC increases with obstructive lung disease and decreases with lung restrictive disease. FRC is also low in the pediatric population. (Table 14 .1) Asthma: Chronic obstructive disease with bronchiolar inflammation and hyperresponsiveness that displays reversible, variable, and recurrent airway obstruction. • Diagnosis: Asthma is a clinical diagnosis, which can be confirmed with a positive response to bronchodilator during a pulmonary function test. should be avoided such as meperidine and morphine. Also, opioids should be used judiciously to decrease the risk of chest wall rigidity. • Use of adenosine and other nonspecific β-blockers (e.g., Labetalol) should be avoided since they will result in bronchoconstriction. • Be cautious using NSAIDs and cyclooxygenase inhibitors as this can induce an asthma attack and rash. Some patients may have Samter's triad (nasal polyps, ASA sensitivity, and asthma) and are also sensitive to the aforementioned drugs. • Be aware of signs and symptoms of bronchospasm and status asthmaticus. Contact EMS for suspected status asthmaticus. Cystic Fibrosis: Autosomal recessive disease resulting in altered chloride and water transport (CFTR gene) across epithelial cells; this prevents sodium reabsorption by epithelial sodium channels. Can impact the respiratory, gastrointestinal, and reproductive systems. • Diagnosis: Sweat chloride concentration exceeding 60 mEq/L in addition to one or more of the following: chronic airway disease, exocrine pancreatic insufficiency, or cystic fibrosis in a first-degree relative. At birth, failure of passing meconium is highly suggestive of CF. • Patients have a high incidence of respiratory infections that manifest as productive cough, pansinusitis, and dyspnea. • Patients may also exhibit signs of malabsorption including diarrhea, constipation, and greasy smelly stools. • Salty crystal accumulation on skin and salty tasting skin. • Heat and exercise intolerance. • Infertility due to azoospermia and atresia of the vas deferens may also be present. • Signs of fat-soluble deficiency: -Vitamin E -peripheral neuropathy and hemolytic anemia. • Management of these patients is best carried out with the aid of pulmonologist or cystic fibrosis specialist. • Optimization of pulmonary status in terms of management of secretions and infections is the key. • Active infections must be ruled out prior to surgery. • Consider chest physiotherapy prior to surgery. • Electrolytes, LFTs, and chest radiographs are useful prior to anesthesia along with continuation of medications. • Risk of developing a pneumothorax is risk high (nitrous oxide should be avoided). • Procedure should be carried out later in the day to allow for clearance of secretions that have accumulated overnight. • Ketamine is relatively contraindicated due to increased secretions. • Prophylactic β agonist with metered dose inhaler is recommended. • Irritant vapors such as isoflurane such and desflurane are less useful than sevoflurane [2] . • Short-acting anesthetic agents such as propofol and sevoflurane may be the most appropriate choice. • Consider arterial line for frequent blood gas monitoring [2] . • Avoid nasal intubation if possible due to higher incidence of polyposis [2] . • COPD is an irreversible disease that causes airway obstruction by either chronic bronchitis and/or emphysema (Table 14. 3). • Risk factors include smoking (most common), respiratory infection, occupational exposure to environmental substances, and alpha-1 antitrypsin deficiency. • Signs and symptoms include wheezing, chronic cough, productive cough, hyperinflation of chest, weight loss, fatigue, and dyspnea on exertion. • Advanced symptoms include pursed lips, cachexia, and pulmonary hypertension leading to neck vein distention and peripheral edema. Oxygen, pulmonary rehabilitation • Chronic bronchitis ("blue bloaters") results in chronic hypersecretion of mucus in the bronchi resulting in increased resistance to airflow and irreversible airway obstruction. • Emphysema ("pink puffers") is enlargement of the airway due to destruction of the airway walls distal to bronchioles. This leads to loss of elasticity/recoil. Symptoms include dyspnea, cough, sputum production, and decreased exercise tolerance. They typically have a barrel chest due to hypertrophy of the accessory muscles used during respiration. • COPD patients typically exhibit hypercarbia and hypoxemia. Advanced disease can lead to pulmonary hypertension and cor pulmonale. • Pulmonary function tests including spirometry are used to confirm suspected COPD. • Bronchitis diagnosis is based on a history of a productive cough that has been present for at least 2 consecutive years. • Blood labs may show hypercarbia, polycythemia, decreased serum alpha 1 -antitrypsin levels, and leukopenia. • Chest radiographs are used to look for evidence of lung nodules, bullae, hyperinflated lungs, masses, or fibrotic changes. • Pulse oximetry at rest, during exertion, and during sleep is useful to evaluate for hypoxemia and the need for supplemental oxygen. • COPD patients should be optimized prior to surgery (consult with a pulmonologist and treatment of active infections). • Smoking cessation for 6 weeks is recommended as oxygen carrying capacity and mucociliary transport improve and has been shown to reduce postoperative pulmonary complications [3, 4] . • EKG to rule out right-sided heart disease and ischemic heart disease [5] . • Chest X-ray warranted if concern for respiratory infection or occult malignancy. • Presence of extensive bullae translates to a higher risk pneumothorax [5] . • Chest physiotherapy prior to surgery to loosen secretions and dislodge mucus plugs. Signs of active infection such a pyrexia, purulent sputum, or worsening cough may warrant delaying surgery until improvement. • Nitrous oxide has the potential to expand and possible rupture pulmonary bullae. • Consider β-2 agonist and an antimuscarinic (e.g., robinul) to increase airway patency. • Prolonged recovery should be anticipated due to air trapping when using inhalational agents. • Avoid over oxygenation as this will cause a ventilation-perfusion mismatch due to inhibition of autoregulatory mechanism known as hypoxic pulmonary vasoconstriction. This leads to more blood flow to poorly ventilated areas. Maintain oxygen saturation between 88% and 92% [6] . • On ventilator, watch out for breath trapping (intrinsic positive PEEP) may lead to right heart strain. Consider increasing inspiratory to expiratory ratio to allow more exhalation time closer to 1:3 to 1:5 [5] . • Chronic hypercapnia leads to a decrease in ventilatory drive in response to elevated CO 2 levels. Chemoreceptors in the medulla oblongata reset and initiate ventilation at a higher concentration of CO 2 . Respiration drive is mostly dependent on anoxic stimulation of peripheral chemoreceptors (another reason to not excessively oxygenate the patient). • Patients have limited ability to tolerate hypoventilation because they have a diminished response to hypercarbia. Opioids diminish the respiratory drive and predispose the patient to apnea (use opioids judiciously). • Local anesthesia is preferred. Pulmonary embolism -acute, partial, or complete obstruction in the pulmonary arterial vasculature leading to a ventilation perfusion mismatch. • Consult with physician managing the patient's anticoagulation to determine whether or not a drug holiday from the anticoagulant is possible. • Obtain preoperative INR if warafin is utilized. • Trend INR and PTT for inpatients that are being bridged to Coumadin®. Generally an of INR < 1.5 is suitable to more invasive procedures and patient is to continue bridging pro- Background • Coronavirus disease 2019 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). • It is a single-stranded, positive sense RNA virus [9] . • SARS-CoV-2 is a betacoronanvirus, one of the four genera of coronaviruses. Betacoronavirus are of great clinical concern in humans as they produce the lineage of viruses that cause the common cold. • The betacoronavirus also circulates in animals, but rarely do the animal viruses infect people. • Previous outbreaks of coronaviruses included SARS-CoV-2 and Middle East respiratory syndrome (MERS-CoV), which are zoonotic and have their origins in bats. There is evidence that SARS-CoV-2 may be originated in horseshoe bats due to similarities in genomic architecture [10] . • Coronaviruses are human viruses that attack the human respiratory system. SARS-CoV-2 is the seventh member of the coronaviruses that infect the human respiratory system. • The first clusters of the novel coronavirus, SARS-CoV-2, appeared in Wuhan, China in 2019 with patients presenting with pneumonia of unknown etiology [11] . • Transmission from person to person occurs through direct contact and droplets spread through coughing, sneezing, and talking. There is a possible role for fomites in that contaminated surfaces can harbor viral particles. • Symptomatic and asymptomatic transmission can occur with a high rate of infectivity. • Increased susceptibility to severe disease in patients with multiple comorbidities (HTN, DM, COPD) and elderly patients. • Men have a higher susceptibility to severe disease compared to women. • African Americans and Latinos are at a higher risk of morbidity in comparison to their White counterparts. • Peptomers on the surface of the virus are the glycoproteins responsible for entry into host cells. • SARS-COV-2 gains entrance through points such as the nasal, ocular, and oral cavity mucosae by binding to the human angiotensin-converting enzyme II (ACE2) receptors in these tissues via the peptomers on the viral surface. • Alveolar epithelial cells have an abundance of cells with ACE2 in the pulmonary parenchyma which is why fulminant lung disease may occur. Binding activates immune cells inducing secretion of inflammatory mediators into the pulmonary vessels. • Associated systemic cytokine storm can lead to widespread thrombosis and multiple organ involvement and has a serious impact on morbidity and mortality. • Complications include acute respiratory disease, acute kidney injury, myocardial injury, thrombotic events, Kawasaki disease, multiorgan failure, and Guillain-Barre syndrome. • Symptoms appear after an incubation period of 1-14 days with 5-6 days being the average [10, 11] . • The most common symptoms at onset include: fever, cough, sore throat, myalgia, fatigue, dyspnea, headache, loss of taste (dysgeusia), and smell (anosmia) [12] . • About 25% of patients have diarrhea [9] . • Rhinorrhea and sore throat surprisingly do not commonly occur [9] . • Most cases are mild and self-limiting. • Severe cases progress to severe pneumonia, acute respiratory syndrome (ARDS), multiorgan dysfunction syndrome, thrombotic manifestations, cardiac arrest, shock, and death secondary to cytokine storm. • On physical exam, patients may appear tachypneic with labored breathing. They typically have fever exceeding 39 °C/102.2 °F (extreme age or immunodeficient patient may not develop fever). • Hypotension may lead to tachycardia and cool extremities. • Ophthalmic signs include conjunctival secretions, injection, and chemosis. • Dermatological signs include erythematous rashes and petechiae. • Polymerase chain reaction tests are standard for diagnosis. Samples include nasal and oral swabs to test for virus RNA. Bronchial fluid can also be sampled for viral RNA. • CBC with differential. -WBC: Low to normal with higher than normal neutrophils. • Elevated CRP, ESR, and D-dimer. • CXR may show infiltrates and evidence of pneumonia. • Computed tomography (CT) scan of the chest may reveal ground glass opacities, perihilar lymphadenopathy, and consolidations. • Maculo-papular, acral, urticariform, vesicular, and vascular obstruction lesions are the most common cutaneous manifestations of COVID-19 [13] . • Common oral manifestations specifically include: xerostomia, vesiculobullous lesions, aphthous-like lesions, dysgeusia, facial pain [14] . • Salivary glands may be a reservoir for the virus. • Cause-effect relationship has not been solved at present; however, research is being conducted on whether or not oral lesions are related to immunosuppression rather than the virus itself. • Temporal and oral pigmented lesions are associated with hydroxychloroquine use. • Mostly supportive (antipyretics, analgesics, fluid resuscitation, and non-ventilator oxygen therapy). Unstable patients may require mechanical ventilation or extracorporeal membrane oxygenation (ECMO). • SARS-CoV-2 is sensitive to ultraviolet light and heat, 75% ethanol, ether, chloroform, chlorine disinfectants, and other disinfectants [15] . • 10% betadine found to be viricidal to particles (need at least 15 seconds of contact). • Judicious use of PPE, face masks, and medical grade N95 masks. • Oral and maxillofacial surgeons and staff are considered to have a considerable risk of transmission due to aerosol producing procedures. There are high viral loads in the sinonasal and oropharyngeal regions; therefore, preoperative baseline testing for risk stratification is paramount. Nasoendotracheal intubation also increases the risk of transmission. • Phone screenings prior to appointments should be considered. • Frequent handwashing, social distancing in waiting areas, and disinfection of high contact areas are mainstays to controlling the spread of the virus [14] . • Consider using negative pressure rooms in the operating room setting for patients with unknown COVID-19 status. • Influenza vaccination should be considered in the midst of the COVID-19 pandemic. • COVID-19 is an ever-evolving pandemic; the prudent surgeon should continue to monitor and follow changing scientific literature and federal, state, and local public health guidelines as well. • Allergic rhinitis is an IgE-mediated inflammatory process of the nasopharynx, oropharynx associated with allergen exposure. -Overall prevalence of about 25-40%, which peaks in childhood and adolescence [16, 17] . -Continuous exposure due to home or work contamination may cause some symptom variability in perennial allergic rhinitis (sinus mucosal thickening and postnasal discharge). -Perennial allergic rhinitis is usually developed in adult life and may be caused by cockroach allergens, fungal spores, or latex. -Generally, occurring in atopic patients [16, 18] . ○ 40% of allergic rhinitis patients also display symptoms of asthma. ○ 70% of asthmatics experience rhinitis. -Associated with asthma, rhinosinusitis, otitis media, sleep disorders, and there is a strong association with dental malocclusion due to chronic mouth breathing [18] . • Nonallergic rhinitis with eosinophilia syndrome (NARES) occurs in middle decades of life and is associated with anosmia, chronic sinusitis, and aspirin intolerance. -Resembles allergic rhinitis but occurs with nonspecific stimuli (e.g., chemical odors and position changes • In seasonal allergic rhinitis, diagnosis mainly depends on accurate history of symptoms concurrent with pollination of offending plants. • Recurrent viral or bacterial infection and tonsillar and adenoidal hypertrophy must be ruled out. IgE is critical to etiologic diagnosis, particularly in severe cases. -Skin-prick test of allergens in question is a quick and reliable method to identifying allergen sensitized mast cells. -An intradermal test may follow if the skin test is inconclusive. • Nasal secretions will be rich in eosinophils and useful for ruling out nonallergic rhinitis when diagnosis is not clear. • Prevent exposure to known offending allergens. • Treatment of symptoms is the most commonly used treatment. • Oral antihistamines in the H 1 class are effective for nasal itching and lacrimation. Firstgeneration drugs are more lipophilic and cross the blood-brain barrier and tend to produce sedation (e.g., diphenhydramine). Secondgeneration drugs are less lipophilic and hence less sedating and have decreased psychomotor impairment (e.g., loratadine and fexofenadine). • Nasal H 1 antihistamines are also available and have been shown as efficacious as oral form (e.g., azelastine). Significantly reduces congestion and itching compared to oral form but may cause alteration in taste and smell [18] . • Decongestants α-adrenergic agents can be used topically for nasal congestion (e.g., oxymetazoline or pseudoephedrine). -Limited use due to rebound rhinitis (in use longer than 5 days) and systemic hypertension are side effects reducing the duration of their efficacy. Its use should be limited for acutely severe rhinitis. -Pseudoephedrine should be avoided in patients with narrow angle glaucoma, urinary retention, pregnancy, and severe hypertension. • Intranasal glucocorticoids are the most effective in relief of established rhinitis (e.g., fluticasone, beclomethasone, and budesonide). Effects occur 7-8 h after administration [18] . Side effects include: -Epistaxis range from 4% to 8% in first 2 weeks [18] . -Local irritation occurs in approximately 10% of patients [18] . -Candida overgrowth is a rare side effect, whereas nasal irritation is a common side effect of this medication. • Immunotherapy or hyposensitization requires gradually increasing concentrations of offending allergens. -This lasts 3-5 years with weekly or monthly injections being the most effective. -Should be avoided in patients with unstable asthma and significant cardiovascular disease. • Systemic monoclonal antibody treatment blocks mast cell and basophil sensitization (e.g., montelukast, zafirlukast, and zileuton). Bosack RC, Lieblich S, editors. Anesthesia complications in the Dental Office Cystic fibrosis and anaesthesia Anesthesia secrets Stoelting's anesthesia and co-existing disease Chronic obstructive pulmonary disease and anaesthesia Oxygen-induced hypercapnia in COPD: myths and facts Perioperative pulmonary embolism: diagnosis and anesthetic management Chapter 77 -Deep venous thrombosis and pulmonary embolism 155 -coronaviruses, including Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) s principles and practice of infectious diseases Evolutionary origins of the SARS-CoV-2 sarbecovirus lineage responsible for the COVID-19 pandemic The epidemiology and pathogenesis of coronavirus disease (COVID-19) outbreak Review of the clinical characteristics of coronavirus disease 2019 (COVID-10) Oral manifestations associated to Covid-19 Oral mucosal lesions in a COVID_19 patient: new signs or secondary manifestations? Transmission routes of SARS-Cov-2 and protective measures in dental clinics during the COVID-19 pandemic Allergies, anaphylaxis and systemic mastocytosis Zitelli and Davis' atlas of pediatric physical diagnosis 40 -allergic and nonallergic rhinitis. 9th ed. Middleton's allergy 2-volume set