Original Article Benefit of Forced Expiratory Technique for Weak Cough in a Patient with Bulbar Onset Amyotrophic Lateral Sclerosis J. Phys. Ther. Sci. 16: 137 141, 2004 MITSUAKI ISHII, RPT 1) 1) Department of Physical Therapy, Maizuru Municipal Hospital: 150 11 Mizoshiri, Maizuru, Kyoto 625-0035, Japan. TEL +81 773-62-2630 FAX +81 773-64-6200 E-mail: mm.ishii@orion.ocn.ne.jp Abstract. The specific purpose of this case study was to investigate whether forced expiratory technique (FET) improves the peak expiratory flow compared to coughing in a 53-year-old man with amyotrophic lateral sclerosis (ALS) who presented with bulbar symptoms. Approximately 12 months after diagnosis, his peak cough flow did not exceed 160 L/min, and cough became ineffective. However, FET could generate peak expiratory flow to a point over the 160 L/min threshold until 14.5 months after diagnosis. As a result, FET delayed the need for tracheostomy. When the forced vital capacity (FVC) was observed to be markedly decreased and it was 1,600 ml, the patient was unable to achieve 160 L/min of peak expiratory flow generated by FET. Patients with bulbar onset ALS who have FVC greater than 1,600 ml may benefit from FET. Key words: Amyotrophic lateral scleroses, Bulbar involvement, Forced expiratory technique (This article was submitted Jun. 29, 2004, and was accepted Sep. 27, 2004) INTRODUCTION Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by loss of motor neurons 1). In approximately 25 percent of patients with ALS, the initial symptoms begin in muscles innervated by the lower brainstem cranial nerves in the bulb (medulla) 2). As bulbar muscle dysfunction progresses, it impairs the retention of optimal breath with a closed glottis, and cough becomes ineffective 3, 4). During cough, high peak intrapulmonary pressures are reached when the glottis is closed, and with opening of the glottis, high expiratory flows are generated. Incomplete glottic closure can exacerbate cough dysfunction and further decrease peak cough flow (PCF) 5). The inability to effectively cough is associated with aspiration or respiratory infection, and is a cause of respiratory failure and death. The author hypothesized that use of the forced expiratory technique (FET) 6) known as huffing, that creates forced expiratory flows through an open glottis, might be useful in the treatment of patients with ALS presenting with bulbar involvement. FET is a technique to assist in the expectoration of secretions. Unlike a cough in which the glottis is closed, FET requires the glottis to remain open. The technique is taught when cough is ineffective. It has been proposed that FET for patients with chronic bronchitis is an important adjunctive therapy 7). However, little has been reported about the effect on FET in the patients with bulbar onset ALS. The essential purpose of this case study was to investigate whether a patient who had bulbar involvement but adequate other muscles function can benefit from FET compared with coughing on the peak expiratory flow.
138 J. Phys. Ther. Sci. Vol. 16, No. 2, 2004 CASE REPORT The patient was a 53-year-old man who noticed dysphagia in November of 2002 and dysarthria in January of 2003. In May, he developed weight loss and was subsequently admitted to the University hospital for further examination and management. During this hospitalization, he was diagnosed with ALS and was prescribed Riluzole. He had no upper motor neuron signs. However, physical examination and an electromyographic study revealed that the patient had lower motor neuron signs in the bulbar and cervical regions. Based on progressive muscular weakness with fasciculation in at least two body regions, he fulfilled El-Escorial diagnostic criteria for suspected ALS 8). Pulmonary function testing revealed 3,730 ml of vital capacity (VC), 102 percent of predicted VC, and 79.8 percent of forced expiratory volume in one second per forced vital capacity (FEV 1.0% ). Arterial blood gas values were ph, 7.445; arterial partial pressure of carbon dioxide (PaCO 2 ), 40.5 mmhg; partial pressure of oxygen (PaO 2 ), 97.8 mmhg; bicarbonate (HCO 3 ), 27.2 meq/l; and base excess (BE), 2.9 meq/l. Seven months after diagnosis, he was referred to our hospital at which time he was examined by physical therapy. His voice sounded nasal. Swallowing was disturbed for solid materials. The patient demonstrated muscular fasciculation, atrophy, and weakness in the tongue. The Gag reflex was decreased, in particular on the left side. Position of uvula was deviated to the right side (curtain sigh). Laryngeal elevation was delayed during deglutition. He could benefit from head rotation to the left side to prevent aspiration. Head rotation can divert material down the opposite pyriform sinus into the esophagus 9). Videofluoroscopic study showed (1) delayed bolus propulsion in the oral phase, (2) residue in velleculae after swallow, and (3) removal of the residue by repeated swallowing. Pulmonary examinations revealed 3,500 ml of forced vital capacity (FVC) and 350 L/min of PCF. The patient was able to clear all tracheal secretions independently. Thus, cough function could be classified functional 10). Respiratory rate was 12 breaths per minute. Oxygen saturation was 97 percent. Muscular fasciculation was also reported in the deltoids and biceps bilaterally. However, weakness of these muscles was not detected in manual muscle testing using Daniels and Worthingham grades 11). This means that death of motor neurons innervating these muscles was less than 40 to 50 percent 11, 12). He could perform all functional activities independently. Nine months after diagnosis, he developed dyspnea in the supine position. The author regarded this postural dependent dyspnea as upper airway obstruction due to paretic pharyngeal muscles 13). Ten months after diagnosis, he complained of being heavy-headed 14) in the upright position. Fifteen months after diagnosis, he developed head drop from weak neck extensor muscles. Manual muscle testing grade of the neck extensors revealed fair (3/5) bilaterally. Muscle weakness of limbs initially developed in the deltoids muscle. Thirteen months after diagnosis, the strength of left deltoids was detected as good (4/5) by manual muscle testing. Fifteen months after diagnosis, the manual muscle testing grade deteriorated to poor (2/5) strength of deltoids and fair (3/5) strength of biceps bilaterally. At this time, in room air, his arterial blood gas values were ph, 7.40; PaCO 2, 50.5 mmhg; PaO 2, 81.8 mmhg; HCO 3, 30.5 meq/l; and BE, 4.6 meq/l. Oxygen saturation was 95 percent. Respiratory rate was 20 breaths per minute. Sixteen months after diagnosis, he agreed to undergo tracheostomy. Nineteen months after diagnosis, he required mechanical ventilation. METHODS The author investigated longitudinal changes of the peak expiratory flow by two different methods and FVC. The two different methods were coughing and huffing (FET). Peak expiratory flow was measured with a peak flow meter (Assess; Health scan products Inc; Cedar Grove, NJ). FVC was measured with the Wright Spirometer (Mark 14, Ferraris Development and Engineering Co, Ltd, London UK). A facemask was connected to the measurement devices (Fig. 1). Peak expiratory flow and FVC were measured three times per session and the maximum value of three measurements was taken. Measurements were performed in the sitting position to eliminate the effect of postural dependent upper airway obstruction due to bulbar muscle involvement.
139 Fig. 1. Measurement methods. Left: the measurement method of forced vital capacity with the Wright Spirometer (Mark 14, Ferraris Development and Engineering Co, Ltd, London UK). Right: the measurement of peak expiratory flow with the peak flow meter (Assess; Health scan products Inc; Cedar Grove, NJ). A facemask was connected to the measurement devices. Fig. 2. Longitudinal changes of the peak expiratory flow. Peak cough flow decreased over time. Peak expiratory flow was consistently greater in the forced expiratory technique compared to coughing. Fig. 3. Longitudinal changes of the forced vital capacity. Forced vital capacity (FVC) decreased over time. When the peak expiratory flow generated by the forced expiratory technique declined to below 160 L/min, FVC had decreased to 1,600 ml. RESULTS Decrease in PCF progressed over time (Fig. 2). Approximately 12 months after diagnosis, PCF decreased to 140 L/min, and the patient could not cough out the airway secretions independently. However, at this time, FET generated 250 L/min of peak expiratory flow. The peak expiratory flow was consistently greater in FET compared to coughing (Fig. 2). Decrease in PCF persisted, but FET maintained peak expiratory flow above 160 L/min until 14.5 months after diagnosis. However, 15 months after diagnosis, FET generated a peak expiratory flow only 140 L/min. At this time, FVC had decreased to 1,600 ml (Fig. 3). DISCUSSION Cough flows less than 160 L/min are ineffective 15). Approximately 12 months after diagnosis, PCF could not exceed 160 L/min. As a result, cough became ineffective. The results of this case study revealed that peak expiratory flow was improved by FET, even though the patient with ALS demonstrated marked PCF decrease due to bulbar involvement. Despite having bulbar involvement, the patient who had adequate both inspiratory and expiratory muscles could generate peak expiratory flow to a point over 160 L/min threshold until 14.5 months
140 J. Phys. Ther. Sci. Vol. 16, No. 2, 2004 after diagnosis. As a result, FET delayed the need for tracheostomy. Thus, FET is beneficial for patients with ALS and possibly other neuromuscular disorders which weaken the bulbar muscle. Nonetheless, FET maintained peak expiratory flow for a prolonged period of time until marked weakness from the progressive effects of ALS produced an inadequate contraction of the ventilatory muscles and a subsequent deterioration in FVC. FET, therefore, may be an important adjunctive treatment for patients with ALS and other neuromuscular disorders who have been diagnosed with bulbar involvement. However, when the FVC was observed to be markedly decrease, and it was only 1,600 ml, the patient was unable to reach 160 L/min of peak expiratory flow by FET. The decrease of FVC was associated with a decrease in peak expiratory flow generated by FET, because peak expiratory flows can decrease from not only bulbar dysfunction but also inspiratory or expiratory muscles weakness 5). When the peak expiratory flow generated by FET declined to below 160 L/min, the patient required tracheostomy. In addition, when FET became ineffective, weakness of deltoids, biceps and neck extensors became apparent, and the arterial blood gas values indicated alveolar hypoventilation. The lower motor neuron cell bodies for the diaphragm are in the upper portion of the cervical spinal cord, segments C3 through C5. Lower motor neurons to neck extensors, deltoids, and biceps originate from the same cervical region. Thus, these muscles usually become weak with the diaphragm. Therefore, weakness of deltoids, biceps, and lower cervical-upper thoracic paraspinal muscles predicts involvement of respiratory muscles 12). The effect of FET was dependent on FVC. Thus, appearance of severe weakness less than poor of deltoids, fair of biceps, and fair of neck extensors may be good indication that the beneficial time for FET in the patients with bulbar onset ALS is over. The rate of neuronal deterioration in patients with ALS appears to vary 16). Therefore, the most beneficial time in the stage of the disease for FET for patients with ALS may be different among individuals. This is the major limitation of this study. However, the author believe that, when cough becomes ineffective in patients with bulbar onset ALS, physical therapists should instruct FET to delay the need for tracheostomy, and because FET is a method which can be performed by the patient independently to eliminate bronchial secretions. REFERENCES 1) Francis K, Bach JR, DeLisa JA: Evaluation and rehabilitation of patients with adult motor neuron disease. Arch Phys Med Rehabil, 1999, 80: 951 963. 2) Mitsumoto H: Classification and clinical feature of amyotrophic lateral sclerosis. In: Amyotrophic Lateral Sclerosis; A Comprehensive Guide to Management. New York: Demos Publications, 1994, pp 1 19. 3) Suarez AA, Pessolano FA, Monterio SG, et al.: Peak flow and peak cough flow in the evaluation of expiratory muscle weakness and bulbar impairment in patients with neuromuscular disease. Am J Phys Med Rehabil, 2002, 81: 506 511. 4) Mustfa N, Aiello M, Lyall RA, et al.: Cough augmentation in amyotrophic lateral sclerosis. Neurology, 2003, 61: 1285 1287. 5) Kang SW, Bach JR: Maximum Insufflation Capacity. Chest, 2000, 118: 61 65. 6) van der Schans CP, van der Mark TV, Rubin BK, et al.: Chest physical therapy: mucus mobilizing techniques. In: Pulmonary Rehabilitation; The Obstructive and Paralytic Condition. Philadelphia: Hanley & Belfus, 1996, pp 229 246. 7) van Hengstum M, Festen J, Beurskens C, et al.: Effect of positive expiratory pressure mask physiotherapy (PEP) versus forced expiration technique (FET/PD) on regional lung clearance in chronic bronchitics. Eur Respir J, 1991, 4: 651 654. 8) Brooks BR: El escorial world federation of neurology criteria for the diagnosis of amyotrophic lateral sclerosis. Subcommittee on motor neuron diseases/ amyotrophic lateral sclerosis of the world federation of neurology research group on neuromuscular diseases and the el escorial clinical limits of amyotrophic lateral sclerosis workshop contributors. J Neurol Sci, 1994, 124: 96 107. 9) Logemann JA, Kahrilas PJ, Kobara M, et al.: The benefit of head rotation on pharyngoesophageal dysphagia. Arch Phys Med Rehabil, 1989, 70: 767 771. 10) Alvarez SE, Peterson A, Lunsford BR: Respiratory treatment of the adult patient with spinal cord injury. Phys Ther, 1981, 61: 1737 1745. 11) Hislop HJ, Montgomery J: Daniels and Worthingham s Muscle Testing: Techniques of Manual Examination. 6th ed. Philadelphia: W.B. Saunders Co, 1995. 12) Bromberg MB: Life support: realities and dilemmas. In: Amyotrophic Lateral Sclerosis; A Comprehensive Guide to Management. New York: Demos
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