In t ro du c t i o n
Amyotr ophic lat er al scler osis (ALS ) is a pr ogr es siv e, neur odeg ener ativ e disor der of the v olunt ary m ot or sy st em that is ch ar ac-
t erized by loss and degen er ation of m ot or neur on s an d their outflow tr act s (Kaplan and Hollan der , 1994). ALS primarily affect s the m otoneur on s of th e cer ebr al cortex , br ain st em , and spin al cor d (Br ow n , 1997;
E ffe c t o f B re ath in g E x e rc i s e o n Im pro v e m e nt o f P u lm on ary F un c t ion in P at ie nt W ith A m y otroph ic
L at e ral S c le ro s i s : Ca s e S tu dy
Ju n g Y ou n g - j on g , B .H .S c ., P .T .
Dept . of Phy sical T her apy , T h e Nation al Cancer Center
국 문 요 약
근 위 축 성 측 색 경 화 증 환 자 에 서 호 흡 운 동 치 료 가 폐 기 능 에 미 치 는 효 과
정영종
국립암센터 물리치료실
근위축성 측색 경화증 (amyotrophic lateral sclerosis : ALS ) 환자에게 있어 호흡기능 장애는 죽음에 이르게 하는 주요 원인 중 하나이다. 본 연구는 근위축성 측색 경화증이 있으며 호흡기능이 약화되어 있는 51세의 여성 환자를 대상으로 호흡운동 치료를 시행한 후 폐기능(pulmonary function)이 증진되었는지를 알아보고자 실시하였다. 연구 대상자는 6주간의 호흡운동 치료 프로그램에 참여하였다. 호흡운동 치료 프로그램은 횡경막 호흡 (diaphr agm atic br eathin g ), 복부근육강화(abdomin al mu scles str engthening ), 지갑입술 호 흡(pur sed lip breathing ), 그리고 동기 유발성 흡기폐활량계(incentive spirometer )를 이용 한 흡기운동 등으로 구성되었다.
폐기능 검사는 이동식 호흡측정기(spirometer : MICROSPIROHI- 198)를 이용해서 시행 하였다. 또한 하지 에르고미터(cycle- ergometer )를 이용해 운동 시간을 측정함으로써 폐 기능의 증진 여부를 알아보았다. 연구 대상자는 6주간의 호흡운동 치료 기간 동안 노력성 폐활량(forced vital capacity : FVC)과 정상 예측치에 대한 노력성 폐활량의 비율 (per cent age of the pr edict ed for ced vit al capacity : %F VC), 그리고 하지 에르고미터의 운동 시간에 있어 현저한 증가를 보였다. 그러나 노력성 폐활량에 대한 1초간 노력성 폐 활량 비(FEV1/ FVC)에 있어서는 약간의 감소를 보였다.
근위축성 측색 경화증 환자에게 6주간의 호흡운동 치료를 실시한 결과, 폐기능의 증진 에 효과적임을 알 수 있었으며, 앞으로 더 많은 연구 대상자에게 그 효과를 알아보는 연 구가 필요할 것이다.
핵심단어: 근위축성 측색 경화증; 폐기능; 호흡운동치료.
Hir ano, 1996). Inv olv ement of the m ot or neurons for the respiratory muscles ev entually leads t o dy spn ea and then r espir at ory failur e, the m ost common cau se of death in ALS (Car oscio et al, 1987; T andon and Br adley , 1985). T he incidence of ALS is .4 t o 2.4 ca ses per 100,000 people worldwide, with a pr ev alence of 2.5 t o 7 ca ses per 100,000 people (Ju er gen s and Kurland, 1980; Mit sum ot o et al, 1998; T andon an d Br adley , 1985).
No cur e exist s for ALS , but m edication s hav e ben eficial effect s . Riluzol (Rilut ec) inhibit s glut am at e r elease and ant agonizes the glut am at e r ecept or , which pr olong s surviv al (Ben sim on et al, 1994).
T he cour se of th e disease is in ex or ably progressive (Arnulf et al, 2000). During th e cour se of the disease, the involvement of various respiratory mu scle gr oups leads t o a r estrictiv e v entilat ory defect and ultim at ely t o hyper capnic r espir at ory in sufficien cy (Arnulf et al, 2000). In the majority of cases, death is r elat ed to r espir at ory ev ent s (Car oscio et al, 1987; T an dan and br adley , 1985). Among the mechanisms of r espir at ory impairment in ALS, diaphragmatic dy sfun ction pr obably play s an import ant r ole (Car oscio et al, 1987). Att ali et al (1997) r eported that diaphr agm atic dy sfun ction , defined as the pr esence of abdominal par adox an d delay ed or abolished r espon ses of th e diaphr agm t o phr enic nerv e or cortical stimulation , w as g ener ally associat ed with dy spn ea. P atient s with ALS usually die from such r espir at ory pr oblem s a s hypo- v entilation cau sing hypoxemia, hypercarbia, or both ; aspiration pneumonitis; other pn eu - monia; and occasionally pulmonary embolism
(Car oscio et al, 1987; Kaplan and Hollan der , 1994). It has been r ecently r eport ed that patient s with ALS exhibit ed featur es typical of diaphr agm par aly sis with compen sat ory u se of in spir at ory neck mu scles, and It w as sugg est ed that diaphr agm atic dy s - function is a major det erminant of dy spn ea in ALS (Att ali et al, 1997; Similow ski et al, 1999).
Respir at ory sympt om s u sually appear lat e, and th e m onit oring of lun g and r espir at ory mu scle function hav e been report ed t o be the best pr ognostic in dicator s in these patient s (F allat et al, 1979; Kaplan and Hollander , 1994; S chiffm an and Beish , 1993).
Nakat o et al (1976) w er e am on g the fir st t o r eport serial pulmonary function studies in ALS . T hey m easur ed lung v olum es an d diffu sin g capacity , but not st atic pr es sur es, in 25 patient s beginning 9 m onth s aft er on set an d at 15, 22, and 33 m onth s . Initial m ean vit al capacity (VC) w as within the norm al r an ge and av er aged 58 per cent of predicted at final measurement . S chiffm an and Beish (1993) r eport ed th at 31 of 36 patient s had r espir at ory mu scle w eakness at pr esent ation , although only 7 complained of any r espir at ory sympt om s. Vital capacity (per cent pr edict ed) w as significantly low er in the symptomatic group (55.9) compar ed with th e asympt om atic gr oup (76.4). It is concluded that early m easur em ent or r espir at ory mu scle str ength in ALS w ith sub sequent follow - up studies may be u seful in det erminin g ov er all pr ogn osis an d in decision m aking .
F or many year s , phy sical ther apist s hav e in struct ed patient s in br eathing ex er cise.
Br eathing inv olv es m ov em ent of m any joint s and contr action and r elax ation of m any mu scles. It is a complex m ov em ent that happen s most of th e tim e without con sciou sness. T h e purpose of br eathing exer cises is to reduce the work of br eathing and to improve the ventilation and perfu sion of the lung s. A s the m ajority of r espir at ory function is w eakened in ALS , br eathing ex er cise an d education is v ery import ant .
T o impr ov e r espir at ory capacity , I ch ose the diaphr agm atic br eathing contr ol, pulsed lip br eathin g , thor acic mobility , incentiv e spir om et er , an d especially str engthening of the abdomin al mu scle during in spir ation .
F allat et al (1979) r eport ed the u se of spir om etry (but not static pr essur es) at the time of diagnosis and serially in a lar ge number of patient s with m ot or n eur on disea se, m ostly w ith ALS . At the tim e of diagnosis , 93.6% of their patient s show ed at least one abnorm ality for the following thr ee par amet er s : for ced vit al capacity (FVC), maximum voluntary ventilation (MVV ), and r esidual v olum e (RV ). Mun sat et al (1988) hav e r eport ed a linear loss of muscle function, including pulmonary function , during the active phase of the illn ess in ALS patient s. Early in the disease, befor e an ar ea of m ot or function such as a limb becom es inv olv ed, ther e is a period of st ability . On ce an ar ea of the body st art s t o w eaken , the declin e in str en gth ov er time is lin ear until the low en d of fun ction is r eached and the plot lev els out without further decline. Althou gh r at es of declin e v ary am ong patient s, the plot s t end to be linear in individual patient s. F VC w as the only m easur e of pulm on ary function in this
study , and it s plot ov er tim e w as also found t o be lin ear (Andr es et al, 1986;
Mun sat et al, 1988).
T he abdominal mu scles ar e the prim ary mu scles of expir ation . T hey also hav e an import ant r ole in au gm enting in spir ation in the upright postur e (Dan on et al, 1979; De T r oyer , 1983). De T r oy er (1983) pr oposed sev er al m echanism s by which abdomin al mu scle r ecruitm ent m ay confer m echanical adv ant age t o the diaphr agm . Abdominal mu scle activity and t on e pr ev ent ex cessiv e short ening of the diaphr agm aft er each contr action , en abling the diaphr agm t o function on a m or e fav or able position of it s length - t ension curve. T he incr ease in abdo- minal pr essur e dev eloped during in spir ation is tr an smitt ed t o the low er rib cage.
During ex er cise, abdominal mu scle activity is ev en mor e import ant . Abdomin al mu scle r ecruitm ent for activ e expir ation begin s at low levels of exercise when minute v entilation ex ceeds 30 L (P ar dy et al, 1984). T h e tidal v olum e incr ease during ex er cise is in both the inspir atory and the expirat ory dir ection s.
T he decr ease in fun ctional r esidual capacity (FRC) is preferentially through the abdominal pathw ay (Grimby , 1968). Displacem ent of abdominal cont ent s upon contr action of th e abdominal musculature pushes the diaphr agm upw ar ds so that it oper at es on a m or e favorable portion of it s length - ten sion curv e durin g in spir ation . Dodd and colleagues (1984) emphasized another mechanism for the r ole of abdomin al mu scles as acces sory mu scles of in spir ation . T hey su ggest ed th at the r ecruitm ent of the abdominal mu scles during exercise leads t o a st orage of elastic and gravitational energy, which, when r eleased
during in spiration, contribut es to gener ation of negativ e pleur al pr essur es an d enhan ced in spir atory flow (Dodd et al, 1984).
Alth ough r espir at ory function play s such an import ant r ole in the pr ogn osis of th ese patient s, ther e hav e been few r eport s of r espir at ory function studies in ALS (Black and Hy att , 1971; Keltz, 1965; Nakano et al, 1976; O Donohue et al, 1976).
A s the majority of patient s pr esenting with ALS alr eady hav e evidence of r espi- r at ory mu scle w eakn ess, I think that it m ay be u seful t o est ablish a baselin e with the effect of pulmonary rehabilitation. Pulmo- nary r ehabilit ation is an int erv ention that can combine exercise, education, and behavior m odification str at egies in an effort t o minimize sympt om s and t o impr ov e qu ality of life (Camp et al, 2000).
Ca s e S t u dy
H i s t ory
A 51- year - old female suddenly ex p er ien ced whole body w eaknes s, follow ed by fatigue especially in the aftern oon appr oxim at ely 7 year s ago. Her w eight w as 58 ㎏, an d height w as 164 ㎝.
Since then , the patient had r eceiv ed som e m edical tr eatm ent s an d phy sical ther apy , but w as not informed of the ex act diagnosis . Aft er 2 y ear s, the diagnosis of ALS est ablished in the patient by clinical examination, electromyogr aphic studies, n erv e con duction stu dies, an d furth er neur ologic pr ocedur es that w er e neces sary t o ex clude other neur omu scular disor der s. T he patient history included an both extremities par aly sis and some sleep disturbance. Aft er par aly sis,
the patient felt extr em e w eakness, had difficulty in w alkin g an d activ e daily living activity . Aft er the hospit alization the cour se of the disease is inex or ably pr ogr essiv e.
T he patient complain ed of feeling fatigu ed and being uncapable of sin ging a son g du e to shortness of br eath , and having difficulty in cou ghing an d deep br eathing . Especially the patient could not perform th e low er extremity ergometer for more than 2 minutes .
T he patient lacked knowledge of ALS , it s effect on r espir ation , m ethods t o contr ol dy spnea, breathing and coughing t echniques, and methods of controlling respir ation during ex er cise. All of these symptom s had been unch anged for 6 m onth s prior t o r eferr al t o breathing rehabilitation program . T he patient and her family were informed of the diagnosis and the pr ogr es siv e natur e of the disease. I believ e it is import ant that the patient an d family be giv en as much inform ation as possible about the disease pr ocess , so that inform ed decision s about car e can be m ade.
T he patient participat ed in g oal setting and tr eatment planning .
E v alu atio n
Respir at ory function test w as perform ed at 6 pm , t wice a w eek , ev ery T u esday and F riday . Respir atory function w as t est ed by a portable spirometer (MICROSPIRO HI - 198).
Spir om etry is con sider ed of v alue, n ot only in det ecting early r espir atory inv olv em ent in ALS , but in det ectin g early r espir at ory inv olv em ent in ALS , but also in pr edicting the cour se of r espir at ory failur e (Kaplan and Hollander , 1994; Rin gel et al, 1993).
Spir om etry w as perform ed w ith the patient w earing a noseclip an d connect ed dir ectly
by a m outhpiece. T he data w as digit ally r ecor ded. T he t est w as perform ed 3 tim es t o m eet r eliability guidelines and the m easur em ent s of the best F VC of thr ee trials w er e r ecor ded, not necessarily fr om the sam e trial. Resting period of fiv e minut e w er e pr ovided to allow ample r ecov ery fr om the fatigue. After the final t esting session , the patient w a s participat ed in the int erview . T he initial r espir at ory function ev aluation w as perform ed for 10 day s as a baseline information .
T re atm e nt
P atient s w er e giv en det ailed education cov erin g the following : br eathing and coughing t echniques, m ethods of contr ol of dy spn ea, sign s of illn ess an d tim e t o seek medical help, energy con servation t echniqu es, nutrition al an d ex er cise guidelines, and body m ech anics. T eachin g the patient and his family the in dication s for and the importance of his treatment decreases anxiety and incr ea ses compliance. T h ese ar e vit al point s to con sider if m axim al tr eatm ent benefit is to be realized and further compli- cation s av oided.
T he m ain obj ectiv e of th e pulm on ary r ehabilit ation pr ogr am w as to pr omot e r espir at ory function by m ean s of br eathing ex er cises . Pulm onary r ehabilit ation m ana - gem ent also inclu ded education about self - m onit oring an d pr ogr es sion of activity . Phy sical th er apy beg an 2 w eek s post - admission and consisted of breathing ex er cises.
T hr ee tim es a day phy sical ther apy session (9 am , 1 pm , 5 pm ), dur ation of 20 minut e w er e plann ed for the patient , 5 day s a w eek , for a 6- w eek period. If the patient
had been fatigued, the patient w as not tr eat ed by the phy sical ther apist . T he fr equen cy an d dur ation of the ex er cise pr escribed depend on the patient s lev el of ex er cise capacity . Repetition s of ex er cises w er e pr ogr essiv ely increased as the patient s dy spnea impr ov ed and the patient w as more able to toler ate the pulmonary r eh abili- tation pr ogr am . During this time, T he patient had a 4 minut e w arm - up and cool- down phases. T he warm - up and cool- down pha ses con sist ed of str et chin g ex er cises for upper and low er extr emities, thor acic mobility ex er cises .
W ong (2000) r eport ed that th e upright sitting position w as con sider ed the position of choice for intervention because the patient s ar ou sal w a s at it s gr eat est , v en t ila t ion - perfu sion r atio w as optim al, and diaphr agm mu scle ex cur sion was maximal in an upright position. In this position, the patient perform ed the br eathing ex er cises . Head an d upper body w as leaned again st the w all v ery r elax ed position . T he w ork of br eathing w as also r educed in that position . T he activ e cycle of br eathing techniques w as incorporated with periods of breathing contr ol, deep br eathing m obilization/ ex er cise, an d cough . During the br eathing contr ol period, the patient w as in stru ct ed t o perform norm al tidal br eathing u sing the low er chest w all and t o r elax his upper chest and shoulder s. Verbal input an d t actile input (ie, the ther apist s han d w as placed ov er th e patient s abdom en ) w er e giv en until the patient w a s able t o achiev e br eathing contr ol. During deep br eathing , the patient w as in struct ed t o inhale deeply thr ough the n ose (ie, slowly ov er 3～5
secon ds) t o in spir atory r eserv e v olum e (w hen he began u sin g his accessory mu scles) and t o exh ale thr ough the m outh passiv ely . T he empha sis w as on low er chest w all expan sion . T her e w er e four r epetition s of deep br eathing follow ed by a period of br eathing control. Before br eathing ex er cises w er e perform ed, m obilization and ex er cise in the form of arm elev ation and thor acic m obility (r ot ation ) ex er cises (10～
20 tim es or as t oler at ed) w er e pr escribed t o optimize the v ariou s st eps of the oxy gen tr an sport sy st em , particularly to stimulat e m axim al inspiration and facilitate mucociliary tr an sport r at e.
F or impr oving of r espir atory fun ction , the patient perform ed the in spir at ory ex er cise u sin g in spir at or , abdomin al mu scle str engthening ex er cise u sing m anu al contact , an d diaphr agmatic br eathing ex er cise with pur sed lip br eathing t echnique. In spir at ory mu scle tr aining and r esistiv e diaphr agm atic br eathing ex er cises m ay be ben eficial while w eaning th e patient with quadriplegia or chr onic pulm onary disease form the v entilat or (Aldrich and Karpel, 1987; Derrick son et al, 1992; Horn st ein an d Ledsome, 1986).
Diaphr agm atic br eathin g exercises increase lung volume and impr ove gas exchange (Levenson, 1992). Ex er cise tr aining of in spir atory mu scles m ay be in dicated t o impr ov e their function (Reid and Dechman , 1995). Energy con serv ation t echniques can be u seful in helping a patient accomplish daily activities w ith less effort expended and t o spr ead the effort thr ou ghout the day (Rin gel et al, 1993).
Str engthening of the abdomin al mu scle has been described a s one of the m ajor aim s of ther apy for r espir at ory fun ction . Abdominal mu scles ar e the prin cipal mu scles of activ e ex pir ation , and cough is lar gely (T an dan and Br adley , 1985), though not ex clu siv ely (Ben sim on et al, 1994), depen dent on the int egrity of this mu scle group. Strengthening ex ercise for the abdo- minal mu scle was to be performed ev ery day . I chose this tr eatm ent appr oach becau se I believ ed the patient did not u se abdominal muscles selectively during breathing. I thought this pr oblem w as one of the r espir at ory failur e.
In spir atory ex er cise u sin g spir omet er was performed in comfortable sitting position .
F ig 1. Spirom etric t esting r esult s (FVC, FEV 1)
F ig 2 . Spirom et ric t esting result s (% FV C, % F EV 1)
R e s u lt s
Spir ometir c dat a w er e illu str at ed gr aphi- cally (F ig 1- 3). F igur es show ed that th e effect of the pulmonary rehabilitation pr ogr am in ALS . Initially , the patient showed severe restrictive pattern as asses sed by a F VC th at w as low er than 50%
pr edicted v alu e. T her e w as a definit e pr ogr es sion t o a low er F VC with 6 con se- cutiv e w eek s of the pulm onary r ehabili- t ation pr ogr am fr om 1230 t o 2130 cc.
T hr ee w eek s aft er the pulm on ary r ehabili- t ation pr ogr am , F VC w as incr eased dr am atically .
At initial ev alu ation befor e pulm on ary r ehabilit ation pr ogr am , she w a s able t o perform the low er - ex tr emity er gom et er for approximately 3 minutes, however the dur ation of ex er cisin g gr adually incr eased t o 20 minut es (F ig 4).
D i s c u s s i o n
Pulm on ary r ehabilit ation pr ogr am , as giv en in this study , w as able t o impr ov e qu ality of life of the patient by deliv ering ex er cise tr ainin g , education , and coping
str at egy t echniques. Despit e the poor pr og - nosis of ALS , I believ e th at pulm on ary r ehabilit ation pr ogr am is an import ant component of the ov er all car e of patient s with this disease. Through active participation in tr eatm ent planning , the patient m ay gain som e sen se of contr ol ov er wh at is happening to her body and enable h er t o cope with fun ctional losses efficiently . T he m ajor impact of pulm onary r ehabilit ation w as impr ov em ent in quality of life.
W eakness of the r espir at ory mu scle is an obligat ory component of ALS . Mor eov er , pr ogr es sion in ALS is fast er than in m ost other chr onic neur omu scular disor der s explaining why r espir atory failur e is th e m ost comm on cau se of death (Juer gen s and Kurlan d, 1980). P atient s w ith amyo- trophic lat eral scler osis with mild r estrictiv e v entilat ory patt ern m ay sh ow r eduction in r espir at ory mu scle fun ction , r apid shallow br eathing , and a pr eserv ed n eur al driv e.
Respir at ory fun ction play s such an import ant r ole in the pr ogn osis in ALS . T hu s, pulm on ary r ehabilit ation pr ogr am inv olvin g br eathing ex er cises is essential treatment in ALS . Since ventilatory fun ction is so con sist ently affected in patient s with ALS , I u sed the spir om etry as a simple F i g 3 . Spir om etric t estin g result s (V50, V 25,
V25/ Ht , MMF , PEFR)
F ig 4 . Ergom et er ex ercise time
and accur ate m ean s t o assess the sev erity and the progression of the disease objectiv ely . Although ALS is u sually fat al, the tim e cour se of the symptom s is quit e v ariable, as emphasized in pr eviou s r eport s (Kaplan and Hollan der , 1994; S erisier et al. 1982).
Impairm ent in F VC is a possible harbinger of a m or e r apid clinical det erior ation .
Spir ometric m easur em ent s show that in a m aj ority of cases, r egar dless of the patt ern of mot or neur on impairment , FVC decr ea ses w ith disease pr ogr ession and is corr elat ed with surviv al (Black and Hy att , 1969; F allat et al, 1979; Nakat o et al, 1976;
Schiffm an an d Belsch , 1989). T he v alues for the patient w as compar ed w ith her pr edicted n orm al v alu e that w as adju st ed by age, sex , and height . F or ced expir ed v olum e in 1 second (F EV 1) and F VC ar e am ong th e most r eliable of spir om etric m easur es. T he decline of F VC is occurr ed in ev ery disease affecting the bellow action of chest w all and expan sion of lun g . T he low F EV 1/ F VC w as r elated t o h er w eak and uncoor din at ed expir at ory effort . F EV1/
F VC r atio of less than 0.6, which indicates a greater degree of chronic airflow limit ation . T he %F VC an d %FEV 1 w er e calculat ed by dividing the actual value by the pr edict ed v alue for her . Mahler et al (1992) found that measures of pulmonary function (%F VC and %F EV 1) w er e r elat ed t o disability . T he most con sistently and significantly r educed measurement was the %FEV1. These finding s pr ovide obj ectiv e confirm ation in pulmonary function of the clinical impr ession during pulmonary r ehabilit ation pr ogr am t o her .
T her e were some limitation s to this study . T hese limit ation s included the lack of
subject s, the inability to det ermine the long - t erm ben efit s of pulm onary r ehabilitation.
More research on pulmonary r eh abilitation pr ogr am is n eeded if ther apist s ar e t o make evidence- based decisions regarding the respi- rat ory function . Randomized studies th at compar e the effect s of differ ent exercise programs in terms of type, fr equency , dur ation , and int en sity of ex er cises, for ex ample, ar e needed. Out com e mea sur es should in clude not only for ce m easur em ent s but m or e import antly , function and quality - of - life m easur es.
Physical and emotional health are affect ed by pulmonary r ehabilitation in ALS. Becau se the patient w as exuber ant , alert , and cooper ativ e, th e patient could g et m or e benefit fr om br eathing ex er cises t o impr ov e tidal v olume, thor acic- cage m obility , in spi- r at ory capacity , and cough efficacy . Abov e all, the patient could find the pleasur es in her life. I believ e that phy sical ther apist s car e an d compassion can h av e an impact on the w ell- bein g of people livin g w ith disea se.
R e f e re n c e s
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