Presentation on theme: "January 15, 2010 Issue AFP J OURNAL R EVIEW Emory Family Medicine Katina Robertson, MD."— Presentation transcript:
January 15, 2010 Issue AFP J OURNAL R EVIEW Emory Family Medicine Katina Robertson, MD
A RTICLES R EVIEWED Peripheral Nerve Entrapment and Injury in the Upper Extremity Vocal Cord Dysfunction Noninfectious Penile Lesions Outdoor Air Pollutants and Patient Health
P ERIPHERAL N ERVE E NTRAPMENT AND I NJURY IN THE U PPER E XTREMITY
P ERIPHERAL N ERVE INJURY Peripheral Nerve Injury (PNI) in UE is common Risk Factors Superficial position Long course through area at high risk of trauma Narrow path through bony canal
A NATOMY AND R ISK F ACTORS ANATOMY AND RELATED RISK FACTORS OF UPPER EXTREMITY NERVE INJURY NerveAnatomyFunctionRisk factors for injury Axillary From brachial plexus, around humeral head, through the quadrilateral space to deltoid/teres minor. Quadrilateral space boundaries: humeral neck, teres major and minor, long head of triceps Motor: deltoid, teres minor. Sensory: skin over lower half of the deltoid Humeral head compresses nerve during extreme abduction. Upward pressure through the axilla. Shoulder dislocation. Compression in quadrilateral space Long thoracic C5 to C7 merge, travel between clavicle and first rib through axilla to serratus anterior muscleLong nerve: 20 to 22 cm Motor: serratus anterior. Sensory: none Sudden upper extremity traction. Shoulder depression with contralateral neck flexion. Prolonged compression (backpacker's palsy) MedianBrachial plexus down anterior arm, at antecubital fossa passes through radial tunnel, dives between two heads of pronator muscle, under flexor digitorum superficialis, through carpal tunnel Motor: Injury at elbow or forearm: Weak wrist flexion, no interphalangeal flexion of thumb, index, and long digitInjury at wrist: none or weak thumb abduction. Sensory: Injury at elbow: proximal forearm painInjury at wrist: sensory loss in the thumb, radial 2.5 digits, and thenar eminence Injury at elbow /forearm: radial tunnel, within pronator teres muscle, under flexor digitorum superficialis. Injury at wrist: carpal tunnel syndrome
A NATOMY AND R ISK F ACTORS ANATOMY AND RELATED RISK FACTORS OF UPPER EXTREMITY NERVE INJURY NerveAnatomyFunctionRisk factors for injury Musculocutaneous C5 to C7 merge into lateral cord brachial plexus, goes through axilla, under coracobrachialis, through biceps and under deep fascia at the elbow Motor: Injury at shoulder: loss in biceps, coracobrachialis, and brachialis. Injury at elbow: none. Sensory: radial side of forearm (dorsal and volar), but not hand Shoulder dislocation. Hypertrophy of the coracobrachialis. Deep brachial fascia of elbow as nerve exits biceps (sensory symptoms only) Radial From brachial plexus, through axilla, down posterior arm until it circles toward anterior arm at spiral groove of the humerus; down anterior arm and enters radial tunnel just above the lateral epicondyleDivides into superficial and deep (posterior interosseus nerve) branches Motor: Injury in axilla: loss of elbow flexion; weak wrist and digit extension; weak forearm supination Injury at elbow: superficial branch (radial tunnel): forearm pain, normal motor; posterior interosseus nerve: weak or no wrist extension. Injury at wrist: no motor loss. Sensory: variable sensory loss in distal forearm or hand. Injury at elbow: no sensory loss; possible pain with repetitive forearm supination Injury in axilla or proximal humerus (fracture). Injury at elbow: radial tunnel or area of proximal radius (fracture or dislocation); two nerve branches from elbow have injury potential, posterior interosseus nerve has mostly motor loss and the superficial branch has only sensory change (pain) Spinal accessoryEmerges through sternocleidomastoid muscle, across posterior neck, dives under trapezius Motor: trapezius. Sensory: none Very superficial course in posterior neck and directly under the trapezius muscle
A NATOMY AND R ISK F ACTORS ANATOMY AND RELATED RISK FACTORS OF UPPER EXTREMITY NERVE INJURY NerveAnatomyFunctionRisk factors for injury Suprascapular From upper trunk brachial plexus, through posterior triangle, across top of scapula and through scapular notch, down posterior aspect scapula and across scapular spine to supraspinatus, infraspinatus Motor: supraspinatus, infraspinatus. Sensory: acromioclavicular and glenohumeral joints Entrapment under transverse scapular ligament that covers the suprascapular notchInjury as it crosses scapular spine or under spinoglenoid ligament Ulnar From brachial plexus down anterior arm; just above medial epicondyle it passes to the posterior compartment and into the cubital tunnel; down ulnar side of forearm into Guyon canal (boundaries are hamate and pisiform bones); splits into deep (motor) and superficial (sensory) branches in canal Motor: no loss or weak thumb adduction, weak digit abduction, and adduction toward center of long digit. Sensory: Injury at elbow: pain ulnar side of forearm with or without paresthesias in ulnar digits. Injury at wrist: paresthesias in ulnar digits Injury at elbow or forearm: cubital tunnel, ulnar nerve irritation with medial collateral ligament deficiency. Injury at wrist: Guyon canal Upper trunk cervical plexus Nerve roots C5 and C6 as they exit vertebral foramina and form upper trunk brachial plexus Motor: infraspinatus, supraspinatus, biceps, and deltoid. Sensory: C5 and C6 dermatomes No protective coverings (epineurium and perineurium) on the nerves after they exit the foramina. Increased risk of stretch injury at neck and shoulder regionsContusion or compression of upper trunk at Erb point
P ATHOPHYSIOLOGY Three categories of nerve injury Neurapraxia– least severe, focal damage of myelin fibers around axon. Limited course (days-wks) Axonotmesis– more severe, axonal injury. Nerve regeneration possible but prolonged (months) and incomplete recovery Neurotmesis– complete disruption of axon. Little chance of regeneration or clinical recovery Mechanisms of nerve injury Direct pressure Repetitive microtrauma Stretch- or compression- induced ischemia
D IFFERENTIAL D IAGNOSIS Consider PNI in pts with pain, weakness, parasthesias not related to known bone/soft tissue/vascular injury Anatomic areaSymptomNerve injuries to consider ShoulderPain or numbnessAxillary Brachial plexus WeaknessAxillary Brachial plexus Long thoracic Spinal accessory Suprascapular ForearmPain or numbnessPronator Radial tunnel WeaknessPosterior interosseous HandPain or numbnessRadial at wrist Ulnar at wrist or elbow WeaknessMedian at wrist Ulnar at elbow SYMPTOMS OF UPPER EXTREMITY NERVE INJURIES
C UTANEOUS INNERVATION & D ERMATOMES
S HOULDER & A RM Axillary Brachial Plexus Long Thoracic Spinal Accessory Suprascapular
A XILLARY N ERVE : Q UADRILATERAL S PACE S YNDROME Mechanism Shoulder dislocation Upward pressure (e.g., from improper crutch use) Repetitive overload activities (e.g., pitching a ball, swimming) Arthroscopy or Rotator cuff repair Symptoms Arm fatigue w/ overhead activity or throwing +/- associated paresthesias of lateral &posterior upper arm Signs Weak abduction Weak external rotation
B RACHIAL P LEXUS : S TINGER Mechanism Collision sports (e.g. football) Symptoms Classic: acute onset paresthesias in upper arm Paresthesias in circumferential pattern (not dermatomal) Short duration: last seconds-minutes Motor symptoms can develop at any point Signs Differentiate from C-spine injury (point tenderness, pain w/ neck motion, bilateral symptoms) immobilize Motor weakness, can occur hrs-days after injury 24hrs, then every few days x 2wks if recurrent stingers w/up the neck for underlying pathology predisposing to injury sporting event: All sxs resolve in 15 min + no C-spine injury may return to play, but repeat exam during event
L ONG T HORACIC N ERVE Mechanism Blow to the shoulder Chronic repetitive traction on nerve (e.g., tennis, swimming, baseball) Symptoms Diffuse shoulder or neck pain, worse with overhead motions Signs Winged scapula and weakness with forward elevation of arm
S PINAL A CCESSORY N ERVE Mechanism Trapezius trauma Shoulder dislocation Iatrogenic (Radical neck dissection, carotid endarterectomy, and cervical node biopsy) Symptoms Generalized shoulder pain and weakness Signs Shoulder asymmetry Shoulder sag, inability to shrug shoulder to ear Weakness of forward arm elevation above horizontal plane Chronic injury trapezius atrophy
S UPRASCAPULAR N ERVE Mechanism repetitive overhead loading Glenoid labrum tear +/- cyst formation at suprascapular notch Symptoms Motor weakness Signs Infraspinatus- weak external rotation of the arm Supraspinatus- weak arm elevation, 90 to 180 degrees Differentiate from rotator cuff tear MRI
F OREARM & E LBOW Median Radial Ulnar
M EDIAN N ERVE AT THE ELBOW : P RONATOR S YNDROME Mechanism pronator teres m. -- compress the median nerve Symptoms Forearm discomfort and aching w/activities requiring repetitive pronation (especially w/elbow extended) +/- Paresthesias in the thumb and first two digits Signs Sensory loss over thenar eminence (not seen in carpal tunnel) Negative Tinel Negative Phalen
R ADIAL N ERVE AT THE ELBOW : R ADIAL T UNNEL & P OSTERIOR I NTEROSSEOUS N ERVE S YNDROMES Mechanism divides into a superficial branch (sensory only) and a deep branch (posterior interosseous nerve) at the lateral elbow– compression at any point Symptoms Pain that radiates from lateral elbow to forearm and wrist Pain with wrist extension or grip (shaking hands, turning doorknob) Generalized hand and forearm weakness Signs Differentiate from lateral epicondylitis (tennis elbow) Both– pain with supination against resistance w/ elbow and wrist extended Both– pain resisted extension of middle finger **Maximal tenderness over anterior radial neck If motor symptoms (weakness of digit & wrist extension)– likely post. interosseous
U LNAR N ERVE AT THE ELBOW : C UBITAL T UNNEL S YNDROME Mechanism Very superficial– injury from acute contusion or chronic compression Symptoms Paresthesias of the fourth and fifth digits elbow pain radiating to the hand (sxs may be worse w/ prolonged or repetitive elbow flexion) Signs Sensory loss Motor: Weak digit abduction, weak thumb abduction, and weak thumb-index finger pinch Late finding– decreased power grip
H AND & W RIST Median Radial Ulnar
M EDIAN N ERVE AT THE WRIST : C ARPAL T UNNEL S YNDROME Mechanism Repetitive fine movements– chronic compression Symptoms Paresthesias of thumb, 2 nd & 3 rd digits +/- forearm pain Signs Hypalgesia (positive LR of 3.1) Abnormality in a Katz hand diagram Positive Tinel & Phalen signs Late findings: weak thumb abduction, thenar atrophy
K ATZ H AND D IAGRAM A.classic carpal tunnel syndrome (CTS) for both hands; B. probable CTS, because of symptoms in palm; C. unlikely CTS
R ADIAL N ERVE AT THE WRIST : H ANDCUFF N EUROPATHY Mechanism Superficial branch of the radial nerve crosses the volar wrist-- vulnerable to compression by anything wound tightly around the wrist (e.g. handcuffs) Symptoms Numbness on dorsal hand (usually on radial side) Signs Decreased sensation to soft touch and pinprick over the dorsoradial hand, dorsal thumb, and index digit Motor intact
U LNAR N ERVE AT THE WRIST : C YCLIST ’ S P ALSY Mechanism Common in cyclists -- ulnar nerve compressed against handlebar during cycling Activities involving prolonged pressure on the volar wrist (e.g., jackhammer use) Symptoms Paresthesias in the 4 th and 5 th digits Weakness uncommon -- motor portion of nerve less superficial at wrist Signs Unless activity is prolonged or chronic-- results of the sensory examination are normal Numbness resolves within hours after stopping the activity
S HOULDER & A RM
F OREARM & E LBOW
H AND & W RIST
D IAGNOSTIC T ESTING Plain XR: fracture or cervical spondyloarthropathy
E LECTRODIAGNOSTIC T ESTING Nerve Conduction Studies– Evaluate motor and sensory nerves; Demyelination = slowing of conduction velocity Helpful in confirming diagnosis in pts with atypical presentations In pts with “classic” presentation, NCS do not change diagnosis or management, i.e. don’t bother EMG– useful in conjunction with NCS to distinguish central vs peripheral neuropathies
T REATMENT O PTIONS
P ERIPHERAL N ERVE I NJURY A football player presents with upper arm paresthesias following a tackle. Which one of the following statements about a brachial plexus nerve injury (i.e., stinger) is correct? (check one) A. Paresthesias typically have a dermatomal pattern. B. The athlete should not return to competition or activity for two weeks. C. Bilateral symptoms make the diagnosis more likely. D. Paresthesias typically have a circumferential pattern.
P ERIPHERAL N ERVE I NJURY A patient works on an assembly line doing repetitive overhead work. He has weakness with external rotation of the right arm and when he raises his right arm above his shoulder. Which one of the following nerves is likely involved? (check one) A. Suprascapular nerve. B. Posterior interosseus nerve. C. Radial nerve. D. Ulnar nerve.
P ERIPHERAL N ERVE I NJURY Which of the following has/have been shown to provide short-term benefit for patients with carpal tunnel syndrome? (check all that apply) A. Nonsteroidal anti-inflammatory drugs. B. Corticosteroid injection. C. Vitamin B 6. D. Splinting.
V OCAL C ORD D YSFUNCTION
Definition: inappropriate vocal cord motion produces partial airway obstruction subjective respiratory distress Normal-- person breathes cords move away from midline during inspiration & slightly toward the midline during expiration Dysfunction-- person breathes cords move toward the midline during inspiration or expiration = obstruction Other terms: paradoxical vocal cord dysfunction, paradoxical vocal fold motion, factitious asthma
C LINICAL P RESENTATION Women >men; Ages Symptoms -- recurrent, subj. resp distress Inspiratory stridor Cough Choking sensation Throat tightness 59% with VCD, previously Dx of asthma Sxs usually mild, intermittent Laryngospasm (subtype of VCD) brief involuntary spasm of vocal cords producing aphonia and acute resp distress common complication of anesthesia Spasmodic Dysphonia hoarseness and voice strain when the abnormal vocal cord motion occurs during speech Vocal Cord Dysfunction
D IFFERENTIAL D IAGNOSIS Vocal Cord Dysfunction
P RECIPITATING F ACTORS Exercise: consider in pts with exercise-induced asthma not improved with bronchodilators Psychosocial Conditions: stress disorder, anxiety, depression, and panic attack Irritants: environmental/occupational ammonia, dust, smoke, soldering fumes, and cleaning chemicals Rhinosinusitis GERD Medications: neuroleptics can cause transient VCD (considered focal dystonic reaction) Vocal Cord Dysfunction
D IAGNOSIS PFT w/ a flow-volume loop = most common diagnostic test expiratory loop = normal inspiratory loop = flattened (c/w extrathoracic upper airway obstruction) Flexible Laryngoscopy = diagnostic standard, direct visualization Vocal Cord Dysfunction
T REATMENT Vocal Cord Dysfunction
V OCAL C ORD D YSFUNCTION Which of the following is/are common triggers of vocal cord dysfunction? (check all that apply) A. Gastroesophageal reflux disease. B. Airborne irritants. C. Anticholinergics. D. Exercise.
V OCAL C ORD D YSFUNCTION Which of the following is/are the most valuable diagnostic tests for confirming vocal cord dysfunction? (check all that apply) A. Methacholine challenge test. B. Flexible laryngoscopy. C. Pulmonary function testing with a flow-volume loop. D. Arterial blood gases.
V OCAL C ORD D YSFUNCTION Which of the following symptoms is/are often present in patients with vocal cord dysfunction? (check all that apply) A. Cough. B. Inspiratory stridor. C. Choking sensation. D. Throat tightness.
N ONINFECTIOUS P ENILE L ESIONS Inflammatory Papulosquamous Neoplastics
A NATOMY Noninfectious Penile Lesions
P SORIASIS Epidemiology bimodal peaks at yo & yo Prevalence 1-2%, up to 40% have GU involvement Symptoms red or salmon-colored, papulosquamous, circinate plaques, w/ white or silvery scales Pruritis Exacerbated by-- stress, excess etoh &tobacco use, acute infections (strep), medications(e.g., beta blockers, lithium) Noninfectious Penile Lesions
P SORIASIS Treatment 1 st line options for localized disease mild to mod strength topical corticosteroids (CS)—qDay Vitamin D3 analogues– qDay or BID Prevent skin atrophy– use <50 mg ultrapotent or <100 mg potent topical CS over long-term dose ultrapotent daily x 2wks then q weekend Lesions may recur when CS discontinued If long-term therapy required, tacrolimus (Protopic) or pimecrolimus (Elidel) may decrease risk of atrophy Refractory cases– dermatology referral Diagnosis Clinical systemic signs (nail pitting, arthritis, other skin) If atypical– punch or shave biopsy Noninfectious Penile Lesions
L ICHEN S CLEROSUS ( BALANITIS XEROTICA OBLITERANS ) Epidemiology All ages; ave age 42yo Prevalence..? 1 in 300 4-6% assoc w/ squamous cell carcinoma (SCC) Signs/Symptoms hypopigmented lesion texture like crinkled paper/cellophane. glans penis and prepuce involv Bullae, erosions, or atrophy phimosis, painful erections, obstructive voiding, itching, pain, and bleeding DDX: carcinoma in situ, leukoplakia, and scleroderma Noninfectious Penile Lesions
L ICHEN S CLEROSUS ( BALANITIS XEROTICA OBLITERANS ) Treatment Goal: decr symptoms & prevent malignant transformation mod to ultrapotent fluorinated topical CS Surgery if persistent dz or h/o SCC Circumcision if limited to glans and prepuce Severe cases– reconstructive surgery Systemic agents (e.g. retinoids) for severe refractory cases Long term f/u to monitor for malignant transformation Noninfectious Penile Lesions
A NGIOKERATOMAS Epidemiology Age >40yo; white males Prevalence <1% Signs/Symptoms well-circumscribed, red or blue papules, 1 to 6 mm Clinical diagnosis Usu glans penis; also involv scrotum, groin, thighs, abdominal wall Involv of penile shaft, suprapubic area, and sacrum a/w Fabry disease– referral needed rare intermittent bleeding, pain, or pruritus Tx options: (if symptomatic) surgery, cryoablation, electrocautery, and laser ablation Noninfectious Penile Lesions
L ICHEN N ITIDUS Epidemiology: uncommon Signs/Symptoms Discrete, slightly elevated, hypopigmented papules, approx 1 mm Can involve upper limbs &abdomen Diff from pearly papules ring-like distribution on coronal sulcus Tx options: for cosmesis-- corticosteroids, vitamin A analogues, cyclosporine (Sandimmune), itraconazole (Sporanox), and phototherapy Noninfectious Penile Lesions
L ICHEN P LANUS Epidemiology: uncommon but ¼ affected have GU lesions Signs/Symptoms raised, violaceous, flat-topped, polygonal papules Fine white streaks (Wickham striae), on surface Pts c/o pruritus and soreness Biopsy ulcerated/indurated lesions to r/o SCC Tx options: variable response Potent CS daily vs Ultrapotent CS qWknd If refractory and isolated to prepuce-- circumcision Noninfectious Penile Lesions
Z OON B ALANITIS Epidemiology : Men ; usu Ages yo Signs/Symptoms Patches bright red or brown, shiny with red specks /spots sharply demarcated occur on glans penis, inner prepuce, or coronal sulcus Lesions – tend to bleed +/- erode Mimic carcinoma in situ-- biopsy Noninfectious Penile Lesions
C ARCINOMA IN S ITU Pre-malignant, restricted to skin Epidemiology: uncircumcised men >60 yo Progress to SCC in 5-30% pts Etiology: Primarily HPV Other factors: smegma, trauma Signs/Symptoms 2-35 mm; involv glans penis, urethral meatus, frenulum, coronal sulcus, and prepuce Lesions= raised, beefy red, velvety, irreg shaped plaques, may ulcerate Velvety plaques of glans = erythroplasia of Queyrat Keratotic plaques on shaft, scrotum, or perineum = Bowen disease approx 50% have pruritus and pain Noninfectious Penile Lesions
C ARCINOMA IN S ITU Dx: shave biopsy adequate Treatment Prepuce only-- circumcision Other-- Mohs micrographic surgery ? Radiation for non-surgical candidates ? Imiquimod (Aldara) fluorouracil, curettage, local excision, laser ablation a/w significant recurrence Noninfectious Penile Lesions
I NVASIVE S QUAMOUS C ELL C ARCINOMA Epidemiology: Rare; 2-3 cases/100,000 men Peak Incidence men >70 yo SCC 95% of penile cancers Risk Factors HPV Lichen sclerosus Smegma Smoking Older age Poor hygeine Foreskin phimosis Signs/symptoms Early stage: painless lump/ ulcer Progress to thickened skin & wart-like growth sometimes a/w foul discharge Noninfectious Penile Lesions
I NVASIVE S QUAMOUS C ELL C ARCINOMA Signs/symptoms (Cont’d) Exophytic or fungating SCC--large, irreg shape Exophytic lesions -- can cause phimosis (mass not visible until prepuce retracted) Endophytic SCC -- ulcerative and infiltrating lesions Noninfectious Penile Lesions
I NVASIVE S QUAMOUS C ELL C ARCINOMA Diagnosis: confirmed w/ biopsy (excision vs incision based on size) Treatment low-grade/low-stage tumors: organ-sparing techniques, (e.g. Mohs micrographic surgery) Prepuce only: circumcision Higher-stage tumors (i.e., T2 to T4): Penile amputation is standard treatment Partial penectomy, laser therapy, radiation, and brachytherapy have been attempted as alternatives to radical penectomy Noninfectious Penile Lesions
S UMMARY DD X
S UMMARY T X O PTIONS
N ONINFECTIOUS P ENILE L ESIONS A patient presents with red plaques on his penis. He also reports a history of silvery scales on his elbows that were diagnosed as psoriasis. Which one of the following statements about this patient’s treatment is correct? (check one) A. A minimum daily dosage of 50 g of ultrapotent topical corticosteroids is recommended. B. First-line treatment includes oral corticosteroids. C. Tacrolimus (Protopic) is inappropriate for long-term use. D. Vitamin D 3 analogues should be reserved for refractory cases. E. Weekend dosing of topical corticosteroids reduces the risk of atrophy.
N ONINFECTIOUS P ENILE L ESIONS A 40-year-old man presents with hypopigmented penile lesions, phimosis, painful erections, and erosions that itch and bleed. The lesions are limited to the glans penis and prepuce. Which one of the following statements about this patient’s condition is correct? (check one) A. Topical corticosteroids aggravate the lesions. B. Lichen sclerosus is usually self-limiting. C. Timely treatment may prevent malignant transformation. D. Circumcision is contraindicated.
N ONINFECTIOUS P ENILE L ESIONS Which of the following penile lesions has/have potential for malignant transformation? (check all that apply) A. Zoon balanitis. B. Lichen sclerosis. C. Angiokeratomas. D. Erythroplasia of Queyrat.
O UTDOOR A IR P OLLUTANTS & P ATIENT H EALTH Ozone PM
A IR POLLUTANTS Federal Clean Air Act– requires EPA to set National Ambient Air Quality Standards (NAAQS) for certain pollutants Six Major Pollutants ozone, particulate matter (PM), carbon monoxide, nitrogen oxides, sulfur dioxide, and lead Outdoor Air Pollutants
A IR POLLUTANTS Does your local area meet EPA standards? Go to Outdoor Air Pollutants
A IR POLLUTANTS AQI = information about local air quality, potential health effects, and actions to take to protect when air pollutants reach unhealthy levels Outdoor Air Pollutants
A IR POLLUTANTS Outdoor Air Pollutants
A IR P OLLUTANTS & P ATIENT H EALTH Which one of the following major air pollutants, or “criteria” pollutants, is thought to be the most widespread and serious threat to health in the United States? (check one) A. Carbon monoxide. B. Particulate matter. C. Nitrogen oxides. D. Sulfur dioxide
A IR P OLLUTANTS & P ATIENT H EALTH Which one of the following statements most accurately reflects the health advice of the U.S. Environmental Protection Agency to the general population when the Air Quality Index is 130 for ozone? (check one) A. Everyone should reduce prolonged outdoor exertion. B. No specific health advice is given. C. Persons with asthma should avoid all outdoor exertion. D. Persons with chronic obstructive pulmonary disease should reduce prolonged outdoor exertion. E. Older adults should avoid prolonged outdoor exertion.
A IR P OLLUTANTS & P ATIENT H EALTH Which of the following actions is/are recommended to reduce exposure to air pollution? (check all that apply) A. Opening windows on sunny days to reduce indoor ozone levels. B. Increasing physical activity. C. Using air conditioning in recirculation mode. D. Adjusting exercise schedules to avoid times of day when air pollution levels are highest.