Over a period of lo years, 7 patients have been referred

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1 nflated. The treatment of pneumothorax ex vacuo should be drected to releve the endobronchal obstructon.1 Ths may consst of aggressve suctonng to remove secretons or mucous plugs, fberoptc bronchoscopy to extract asprated foregn bodes or nspssated plugs, or repostonng of a malpostoned endotracheal tube. 1 Chest tube placement may not result n reexpanson of the collapsed lobe n the face of endobronchal obstructon 5 6 and s not ndcated. 1 The dagnoss s confrmed when the ntrapleural gas spontaneously resolves after the endobronchal obstructon s releved and the lobe reexpands (Fg l-3). REFERENCES Berdan WE, Dee GJ, Abramson ST, et al. Localzed pneumothorax adjacent to a collapsed lobe: a sgn of bronchal obstructon. Radology 1984; 150: Rgby M, Zylak CJ, Wood LDH. The effect of lobar atelectass on pleural flud dstrbuton n dogs. Radology 1980; 136: Lams PM, Jules H. The effect oflobar collapse on the dstrbuton offree ntrapleural ar. Radology 1982; 142: Kurlander GJ, Helmen CH. Subpulmonary pneumothorax. AJR 1966; 96: Galvs AG, Bowen A, Oh KS. Nonexpandable lung after dranage of pneumothorax. AJR 1981; 136: Tanaka F, Ezak H, lsobe J, et al. Four cases of spontaneous pneumothorax wth no reexpanson of collapsed lung despte chest tube dranage. Kyobu Geka 1992; 45: nterventons: The patents were treated wth nocturnal nonnvasve ventlaton wth ether an ndvdually constructed curass shell and a negatve pressure pump or nasal ntermttent postve pressure ventlaton usng a volume preset ventlator. Measurement and results: Each patent underwent an ntal clncal assessment along wth radologc studes of the spne, pulmonary functon tests, daytme arteral blood gas tensons, and overnght recordngs of arteral saturaton, and transcutaneous carbon doxde tenson. They were reassessed n detal at a mean of 5 years after startng ventlatory support. Symptoms, vtal capacty, daytme carbon doxde tenson, and overnght oxmetry had all mproved followng treatment. Temporary wthdrawal of ventlatory support led to severe sleep fragmentaton n four patents and the appearance of central apneas and hypopneas n the other three. Sx of the 7 patents were alve at a mean of 5. 7 years after startng nocturnal ventlaton. Concluson: These results show that ventlatory falure may develop, after an nterval of many years, n patents wth a severe thoracc kyphoss due to tuberculoss n chldhood. Nonnvasve nocturnal ventlatory support can control the symptoms of ventlatory falure, mprove the physologc abnormaltes, and s assocated wth prolonged survval. (CHEST 1996; 110: ) Kyphoss Secondary to Tuberculoss Osteomyelts as a Cause of Ventlatory Falure* Clncal Features, Mechansms, and Management an E. Smth, MA; Clare Z'vl. Laroche; Sarah A. Jameson; and John M. Shneerson, MD Study objectves: To nvestgate the relatonshp of thoracc kyphoss followng tuberculoss to the development of ventlatory falure and to assess the effcacy of nocturnal nonnvasve ventlatory support. Desgn: Retrospectve consecutve case seres wth crossover from a phase wthout nonnvasve ventlatory support to a phase wth ths treatment. Settng: The Respratory Support and Sleep Centre, Papworth, Hosptal, Cambrdge, England. Patents: Seven patents wth thoracc kyphoss followng tuberculous osteomyelts whch had been contracted by the age of 4 years were studed. Ther mean age was 53 (SD 7.1) years and the mean angle of kyphoss was ll3.60. All patents were n ventlatory falure. *From The Respratory Support and Sleep Centre, Papworth Hosptal, Cambrdge, England. Manuscrpt receved November 6, 199.5; revson accepted May 1, Reprnt requests: Dr. Smth, The Respratory Support and Sleep Centre, Papworth Hosptal, Papworth Ewrard, Cambrdge, England CB3 8RE.. Key words: kyphoss; mechancal ventlators; respratory nsuffcency Abbrevatons: Dl=desaturaton ndex (number of dps n Sa02 >4% per hour); Pemax=maxmal expratory mouth pressure; Pmax=maxmal nspratory mouth pressure; PtcCOz=transcutaneous partal pressure of COz; REM=rapd eye movement; Sa02=arteral oxyhemoglobn saturaton; TLC=totallung capacty; TSa02 <90%=percentage of tme overnght when Sa02 <90%. Over a perod of lo years, 7 patents have been referred to the Respratory Support and Sleep Centre, Papworth Hosptal, Cambrdge, England, wth ventlatory falure assocated wth kyphoss and no other respratory dsorder. No prevous report has analyzed ths assocaton or the outcomes of treatment. We therefore examned the clncal and physologc factors whch mght have caused ventlatory falure n ths group of subjects and present the results of treatment wth long-term nocturnal-asssted ventlaton n the home. Subjects MATERALS AND METHODS The records of all patents referred to the Respratory Support and Sleep Centre who had kyphoss and subsequently receved asssted ventlaton were examned. Patents wth an assocated scoloss, a neuromuscular dsease, prevous pulmonary tuberculoss, or another pulmonary dsorder, such as chronc bronchts, were excluded. Seven patents fulflllng the entry crtera for the study were referred to the center between May 1983 and July All patents gave ther nformed consent for ncluson n the study. CHEST OCTOBER,

2 Table -Changes n Hemoglobn, Daytme Arteral Blood Gas Levels, and Overnght Montorng Between Referral and Reassessment* ntal Referral Reassessment Admsson Hemoglobn, gcll Pa02, mm Hg PaC02, mm Hg Mean overnght Sa02, % Mnmum overnght Sa02, % TSa02 <90%, % D, dps >4% per hour Mean overnght PtcC02, mm Hg \-lean : SD Mean SD 14.: t *The mean perod between the 2 admssons was.5.08 years; the overnght results on reassessment are those assessed \Vth patent recevng asssted ventlaton. 1Sgnfcant dfferences between results at ntal referral and the reassessment admsson are p<0.05. Sgnfcant dfferences between results at ntal referral and the reassessment admsson are p<o.ol. Study Desgn Assessment at ntal Referral: nformaton was obtaned regardng age of onset of the spnal deformty, duraton, and nature of symptoms related to ventlatory falure, and tobacco consumpton. A complete physcal examnaton and an ECG were performed. Plan radographs of the thoracc spne were obtaned to determne the level of the kyphoss, and the angulaton was estmated usng Cobb's method 1 The hemoglobn concentraton and the hematocrt level were measured. Pa02 and PaC02 were measured wth the patent at rest breathng room ar. The FEV1 and FVC were measured usng a cl1y sprometer (Vtalograph;). Functonal resdual capacty was measured by helum dluton (P. K. Morgan; Gllngham, Unted Kngdom) and total lung capacty (TLC) and resdual volume were calculated. All volumes were corrected to body temperature, pressure, and saturaton and expressed as a percentage of the predcted value calculated on the arm span rather than heght to account for the spnal clefonnty 2 Maxmum mouth pressures were recorded usng a calbrated v a ~ areluctance b l e pressure transducer (S-Plan Electroncs Research; Stratford-upon-Avon, England) and e:\-pressecl as a percentage of predcted values calculated from regresson equatons accordng to a prevously descrbed method: 3 The arteral o:\yhemoglobn saturaton (Sa02) was recorded contnuously overnght usng ether an ear oxmeter (Hewlett Packard; San Dego) or a pulse oxmeter (Box 3700; Ohmeda; Herts, UK) and the transcutaneous partal pressure of C02 (PtcC02) was recorded usng a heated polarographc electrode (TCM3; Radometres; Copenhagen). A two-channel recorder, wth the paper speed set at 1 mm/mn, was used to produce a hard copy. From the paper tracngs, the mean and mnmum Sa02levels, the percentage of tme overnght when Sa02 was less than 90% (TSa02 <90% ), the desaturaton udex (D [number of dps n Sa02 greater than 4% per hour]), and the mean and mnmum PtcC02 were calculated and recorded. The ndcatons for the ntaton of asssted ventlaton and detals of the technque of ventlatory support were recorded. Any changes n the method of asssted ventlaton durng subsequent admssons and the reasons for such changes were recorded. Reassessment Admsson: Behveen July 1993 and May 1994, the 7 patents were reassessed n detal. All of the nvestgatons perfonnecl at ntal referral were repeated. n order to observe abnormaltes n nocturnal ventlaton and to reassess the need for treatment, a controlled wthdrawal of asssted ventlaton was performed. The patents were montored on the frst nght usng the ventlator system whch they used at home. On the second and thrd nghts, asssted ventlaton was wthdrawn. On all three nghts, Sa02 and PtcC02 were recorded contnuously. On the 3rcl clay, mtelal blood gas tensons were measured and on the 4th nght polysomnography was performed (Bomedcal Montorng Systems amplfers and Sleepmaster conputer). Chest and abdomnal movements were recorded usng nductance plethysmography bands (Resptrace) and nasal -oral arflow was measured wth a thermstor. Sa02 was measured usng a pulse oxmeter. The EEG was staged usng standard crtera 4 5 the record was scored for sleep efflcency, and the apnea-hypopnoea ndex was calculated. Statstcal Analyss Correlaton behveen the angle of the kyphoss and pulmonary functon tests at presentaton, the daytme blood gas tensons, hemoglobn levels, and overnght measurements of Sa02 and PtcC02 were examned usng Kendall's ranked correlaton coeffcent. Dfferences were sought behveen the results of the laboratory nvestgatons at frst referral and those on the frst day of the reassessment admsson usng the \Vlcoxon's matched-pars sgned-rank test. The analyss was performed usng the SPSS package (SPSS; Chcago). Probablty results of less than 0.05 were accepted as sgnfcant. ntal Referral RESULTS Clncal Detals at ntal Referral: The 7 patents ( 4 men) had a mean age at referral of 53 years (SD 7.09). All had had tuberculous osteomyelts of the spne before the age of 4 years (mean age, 2.2 years; SD 1.1). Ths had affected the upper thoracc spne n two patents and the mdthoracc spne n fve. The mean angle of kyphoss at presentaton was (SD, 14; range, 95 to 135 ). The patents had been treated vvth bedrest and plaster braces. None had receved correctve surgery, and only one had receved anttuberculous chemotherapy. All patents were ex-smokers (mean number of pack-years was 14; SD 12.6), but none complaned of a productve cough or had wheezng on examnaton. All 7 patents descrbed ncreasng dyspnea on exerton over a perod of at least 4 years. At referral four had dyspnea walkng on the flat surface and three had dyspnea at rest. Two patents had mornng headaches and all seven descrbed dsrupted sleep and daytme somnolence. Sx patents were beng treated wth duretcs, but three of these had persstng perpheral edema Selected Reports

3 Table 2-Changes n Pulmonary Functon Between Referral and Reassessment ntal Referral Reassessment Admsson Mean SD Mean SD FEV1, % of predcted FVC, % of predcted FEV 1/FVC rato, % TLC, % of predcted Resdual volume, % of predcted Pmax, % of predcted Pemax, % of predcted * *Sgnfcant dfferences between results at ntal referral and the reassessment admsson are p<o.ol. Sgnfcant dfferences between results at ntal referral and the reassessment admsson are p<0.05. The percent of predcted values for Pemax at presentaton could not be calculated snce results for 5 patents were recorded only as more than 100 em H20. Physologc Measures at ntal Referral: All 7 patents had p pulmonale, rght axs devaton, and evdence of rght ventrcular hypertrophy on an ECG. The results of the arteral blood gas estmatons are shown n Table l. The daytme restng PaC02 was greater than 50 mm Hg n 6 patents (mean, 53.7 mm Hg; SD 7.30). Results oflung functon tests at ntal referral are shown n Table 2 and demonstrate a restrctve pattern. n 6 patents TLC and resdual volume were both reduced to less than 50% of predcted. Maxmal nspratory mouth pressure (Pmax) was less than 50% of predcted n 2 patents and greater than 85% of predcted n only 2. n 5 patents, maxmal expratory mouth pressure (Pemax) was recorded only as greater than 100 em H 20 and so the percentages of predcted values could not be calculated. However, usng a fgure of 100 em H20 for these 5 patents, Pemax was at least 85% of predcted for 6 patents and 36% of predcted for the remanng patent. The complete results of overnght montorng at ntal referral are gven n Table 2. Of partcular note s the low level of the mean overnght Sa02 (mean, 81 %; SD, 4.2), and TSa02 <90% (mean, 86%; SD, 12.3). 50 ~ -::;-- 40 ~ There was no correlaton between the angle of kyphoss on the one hand and the hemoglobn concentraton, daytme arteral blood gas tensons, the overnght oxmetry measures, or maxmal mouth pressures on the other hand. There was no overall correlaton between the Cobb angles and the measures oflung volume. However, one patent, who dd not have any other unusual measurements, dd have larger lung volumes despte havng the most pronounced kyphoss. f the data of ths patent are excluded, there s a strong nverse correlaton between the angle of kyphoss and FEV 1, TLC, and n partcular FVC (r= -0.88; p=0.02) wth each expressed as a percentage of the predcted value (Fg 1). Progress: Nonnvasve nocturnal-asssted ventlaton was commenced n all patents. n sx patents, the ndcaton was stable ventlatory falure wth an elevated daytme PaC02. The remanng patent had relatvely normal daytme blood gas tensons (Pa02, 70 mm Hg; PaC02, 41.4 mm Hg) but had a mean overnght Sa02 value of 79% and a PtcC02 level of 53 mm Hg assocated wth perpheral edema that dd not resolve wth treatment wth duretcs. Curass ventlaton usng customzed shells 6 and the Newmarket negatve pres _._ J Q) u :..0 ~ 30 a. ~ Q) = Q) ~ 20 ' ' u Q:; a. 10 t :;: '-'- 0 l l ' Cobb Angle (degrees) FGURE l. Forced vtal capacty (percentage predcted) aganst angle of kyphoss. There was no overall relatonshp between vtal capacty and the Cobb angle. However, f the outler (astersk) s excluded, r=-0.88 (p=0.02). * CHEST/110/4/0CTOBER,

4 sure pump (S-Plan Electroncs Research; Stratford-upon Avon, England) was begun for the three patents referred to the center before The other 4 patents, referred after 1988, began recevng nasal ntermttent postve pressure ventlaton usng standard masks (Resproncs; Murrysvlle, Pa) and the Monnal D postve pressure ventlator n assstcontrol mode (Taema; Pars, France). None of the patents requred addtonal oxygen therapy at ths stage. The dose of duretcs was reduced n all patents takng them, and the duretcs were dscontnued completely n two patents. All patents have been followed up at regular ntervals. One patent who had been recevng curass ventlaton deterorated after an nterval of 29 months wth a hstory suggestve of obstructve sleep apnea and perpheral edema. Overnght montorng showed a D of 28, a mean Sa02 of 83%, and a TSa02 <90% of 88%, although daytme arteral blood gas values were normal. He was converted to nasal ntennttent postve pressure ventlaton usng a Monnal D ventlator wth an mprovement n hs symptoms and resoluton of the perpheral edema. Subsequent overnght montorng revealed a D of 4 and a mean Sa0 2 of90%. One other patent who had been recevng curass ventlaton deterorated after a perod of 34 months wth recurrent hypoxema and perpheral edema (overnght mean Sa02, 81 %; TSa02 <90%, 100%) but no evdence of obstructve sleep apnea. The overnght PtcC0 2 showed that he was well ventlated, and daytme PaC02 whle the patent was breathng ar was only 43.6 mm Hg. Oxygen therapy was ntroduced to correct hypoxema. He ded of bronchopneumona a lttle more than 9 years after hs ntal referral. Postmortem examnaton confrmed rght ventrcular enlargement and dlated man pulmonary arteres, whch was consstent wth pulmonary hypertenson. Reassessment Admsson The mean perod between the ntal referral and the wthdrawal studes was 5.08 years (SD 2.50). Wth the excepton of one, all the patents thought that ther symptoms were well controlled usng nocturnal nasal ventlaton wth the Monnal D or curass ventlaton. Sx patents reported breathlessness on nclnes only and had no mornng headaches or daytme somnolence. The remanng patent, who ded 3 months after ths admsson, was breathless on mnmal exerton and complaned of nsomna. None of the patents had perpheral edema. mprovements were demonstrated n the daytme arteral blood gas values wth a statstcally sgnfcant fall n the PaC02. The dynamc lung volumes mproved n all patents and the dfferences were statstcally sgnfcant (p<0.05) although the changes were small. There were no statstcally sgnfcant changes n maxmal mouth pressures. n four patents, however, the Pmax was lower at reassessment, and one patent was too breathless to repeat the measure. Overnght montorng showed sgnfcant mprovements n the mean and mnmum Sa02 levels and n the TSa02 <90%. The complete results are gven n Tables 1 and 2. The ECG had not altered n any of the patents. The arteral blood gas levels on the lst and 3rd days of the reassessment admsson were not sgnfcantly dfferent. However, there were dfferences n the overnght oxmetry traces on the frst and fourth nghts, wth and wthout asssted ventlaton, respectvely. Usng Wlcoxon's matched-pars sum-ranked test, the mean overnght Sa02 was sgnfcantly lower (p=0.04; mean dfference, 6.7%) as was the mnmum Sa02 (p=0.03; mean dfference, 17.3%). The other major fndng on the fourth nght, when polysomnography was performed, was that 3 of the 7 patents slept very poorly wthout ventlatory support (sleep effcency <70%) and one dd not sleep at all. As a consequence, the studes were termnated early n these four patents and ventlatory support was restarted durng the nght. n the 3 patents who spent the whole nght wthout asssted ventlaton, the mean sleep effcency was 83% and mean apnea-hypopnea ndex was 14.7/h. None of the seven patents had obstructve apneas, but central apneas and hypopneas were demonstrated whch were most frequent n rapd eye movement (REM) sleep. DSCUSSON We have reported 7 patents wth ventlatory falure assocated wth thoracc kyphoss. Ths has only been prevously documented n a few case reports, 7-10 but t may be that the assocaton s more common than s apparent from the lterature. Many seres report patents wth kyphoscoloss and ventlatory falure. 11.l2 A true kyphoscoloss s very rare, and whle the term usually s used as a synonym for scoloss, t s possble that some patents wth a genune kyphoss have been ncluded wth the scolotc subjects n prevous seres. Ths dstncton s mportant because both the etology of kyphoss and scoloss and the abnormaltes of the respratory mechancs observed n them are very dfferent. All seven of our patents had had tuberculous osteomyelts n the thoracc spne. Ths s recognzed to cause a sharp kyphoss or gbbus whle scoloss s usually absent or trval. The normal thoracc kyphoss has a range of 20 to 40,1-3 whle n our patents the mean value was n all of the seven subjects, the kyphoss nvolved the upper or mdthoracc vertebrae. Tuberculoss usually nfects the vertebrae of the thoracolumbar juncton, but t s only when t damages the thoracc vertebrae that mportant respratory consequences would be antcpated. The effects of thoracc scoloss on respratory mechancs have been extensvely nvestgated. 14 There s a large decrease n the complance of both the lungs and the chest wall n adults wth a Cobb angle of greater than 100. The respratory muscles on ether sde of the asyn1metrcal chest are affected dfferently, and the overall nfluence on maxmal mouth pressures appears to depend on the severty of the angulaton. n mld scoloss, wth an angle of less than 30, Pemax has been shown to be reduced more than Pmax, 15 whle n more severe scoloss wth an angle greater than 60, Pmax has been found to be consderably reduced whle Pemax was preserved. 16 Wth kyphoss, the chest wall may be greatly deformed but remans symmetrcal and the changes n orentaton of the respratory muscles are dfferent from those seen wth scoloss. n our patents at referral, Pmax was less than 85% of predcted n all but 2 patents, whle Pemax was greater than 85% of predcted for all but l patent. t seems lkely from our fndngs that despte the 1108 Selected Reports

5 small lung volumes, daphragm functon s mpared, possbly because t s at a mechancal dsadvantage due to ts abnormal orentaton. n all of our patents, the kyphoss was apparent by the age of 4 years. Ths has been a feature of the prevously reported cases, and an ncreased rsk of ventlatory falure has been demonstrated n patents wth scoloss of early onset. 17 The number of alveol normally ncreases untl around the age of 8 years but t only does so n response to the mechancal forces generated by the chest wall. The falure of the thoracc cavty to develop, the presence of abnormal respratory mechancs due to the kyphoss tself, and the ankyloss of the costovertebral jonts may have prevented the usual number of alveol from beng formed. 18 Ths would contrbute to the restrctve defct seen n our patents. Ventlatory falure only developed 43 to 61 years after the kyphoss was notced, suggestng that t may have been precptated by changes assocated wth agng, such as reducton n respratory drve or chest wall complance. Loss of respratory muscle strength probably was a contrbutory factor because the Pmax was reduced n all but two patents. n other patent groups treated wth asssted ventlaton, maxmal mouth pressures have mproved, and t has been argued that ths may reflect the relef of respratory muscle fatgue. 19 Because there was no overall mprovement n mouth pressures after effectve treatment n these patents wth kyphoss, we would argue that respratory muscle fatgue was not an mportant factor n the development of ventlatory falure. The patents have been followed up for a mean of5.7 years (SD, 2.52), and 6 of the 7 patents are stll alve. One patent, aged 62, ded a lttle more than 9 years after the ntaton of asssted ventlaton. Rght heart falure (cor pulmonale) has been reported prevously n patents wth kyphoss, 20 and n one seres all four patents ded. 21 Perpheral edema was present n three of our patents at the tme of frst referral. Ths resolved n each case once asssted ventlaton had been ntroduced. The electrocardographc changes of rght ventrcular hypertrophy dd not, however, mprove and the patent who ded had postmortem evdence of pulmonary hypertenson, whch was probably a factor n hs death. At reassessment, the mean Sa0 2 at nght mproved compared wth that at presentaton; the values ncreased from 81 to 92% (p=o.oool). The daytme PaC0 2 fell sgnfcantly between presentaton and the reassessment admsson (mean nterval, 5.08 years). Smlar mprovements n daytme blood gas tensons have been demonstrated prevously wth asssted ventlaton n other chest wall dsorders, such as scoloss,u and after thoracoplasty 19 but not n kyphoss. nterestngly, on the fourth nght of the reassessment admsson n the present study, only three of the seven patents were able to tolerate the whole nght off ther ventlators. n all patents, there was a deteroraton n the mean overnght Sa02 after ths short perod wthout asssted ventlaton. n a prevous study of the wthdrawal of ventlatory assstance for a perod of 15 days, smlar changes n nocturnal gas exchange values were found. 22 Our results suggest that even shorter perods of wthdrawal may be deleterous. None of our patents demonstrated obstructve sleep apnea when self-ventlatng at nght. The records of the three subjects who managed to complete the fourth nght of the reassessment admsson wthout asssted ventlaton showed central apneas and hypopneas whch were most frequent n REM sleep. There have been no prevous polysomnographc studes n kyphotc subjects to compare wth the fndngs of the present study. The present observatons suggest that ether the reducton n bochemcal ventlatory drve n REM sleep compared wth non-rem sleep and wakefulness or the loss of accessory muscle actvty n REM sleep was responsble for these apneas and hypopneas. These fndngs suggest that ventlatory falure wth kyphoss s assocated wth an onset of deformty n early chldhood and may be more common than has been prevously recognzed. The cause of the development of ventlatory falure after an nterval of over 40 years remans uncertan, but t seems that respratory muscle weakness s a factor and that abnormaltes n nocturnal ventlaton precede the deteroraton n daytme arteral blood gas values. We have shown that treatment wth nocturnal asssted ventlaton s well tolerated and can effectvely control symptoms and mprove physologc abnormaltes n the majorty of patents. REFERENCES 1 Cobb JR. Outlne for the study of scoloss. Am Acad Ortbop Surg 1948; 5: Lnderhom H, Lndgren U. Predcton of sprometrc values n patents wth scoloss. Acta Orthop Scand 1978; 49: Wlson SH, Cooke NT, Edwards RHT, et al. Predcted normal values for maxmal respratory pressures n caucasan adults and chldren. Thorax 1984; 39: Ryan CF, Lowe AA, LD, et al. Magnetc resonance magng of the upper arway n obstructve sleep apnea before and after chronc nasal contnuous postve arway pressure therapy. Am Rev Respr Ds 1991; 144: Rechtschaffen A, Kales A. A manual of standardsed termnology, technques and scorng system for sleep stages ofhuman subjects. Bethesda, Md: US Government Prntng Offce; Natonal nsttutes of Health publcaton Brown L, Knnear WJM, Seargent KA, et al. Artfcal ventlaton by external negatve pressure: a method for makng curass shells. Physotherapy 1985; 71: Brlle D, Hatzfeld C, Lejeune F. Le tratement de 'hypoventlaton alveolare dans a defallance cardo-respratore des gbbeux. J Fr Med Chr Thor 1963; 17: Gmenez M, Pham QT, Vttoz-Polu E. Aspects partculers de a reeducaton des gbbeux, nsuffsants respratores. Ann Med Physque 1969; 12: Prowse CM, Gaensler EA. L' nsuffsance respratore ague des gbbeux. Anesthesology 1965; 26: Turno GM, Goldrng RM, Fshman P. Cor pulmonale n musculoskeletal abnormaltes of the thorax. Bull NY Acad Sc 1965; 41: Ells ER, Grunsten RR, Chan S, et al. Nonnvasve ventlatory support durng sleep mproves respratory falure n kyphoscoloss. Chest 1988; 94: Gullemnault C, Kurland G, Wnkle R, et al. Severe kyphoscoloss, breathng, and sleep. Chest 1981; 79: Moe JH, Wnter RB, Bradford DS, et al. Scoloss and other spnal deformtes. Phladelpha: WB Saunders, 1978; Baydur A, Mlc-Eml J. Respratory mechancs n kyphoscoloss. Monald Arch Chest Ds 1993; 48: Smyth RJ, Chapman KR, Wrght TA, et al. Pulmonary functon n adolescents wth mld dopathc scoloss. Thorax 1984; 39: Cooper DM, Velasques Rojas J, Mellns RB, et al. Respratory CHEST /110/4/ OCTOBER,

6 mechancs n adolescents wth dopathc scoloss. Am Rev Respr Ds 1984; 130: Branthwate MA. Cardorespratory consequences of unfused dopathc scoloss. Br J Ds Chest 1986; 80: Berend N, Marln GE. Arrest of alveolar multplcaton n k)phoscoloss. Pathology 1979; 11: Jackson M, Smth E, Kng MA, et a. Long term non-nvasve domclary asssted ventlaton for respratory falure followng thoracoplasty. Thorax 1994; 49:9L Hanley T, Platts MM, Clfton M, et a. Heart falure of the hunchback. Q J Med 1958; 27: Coombs CF. Fatal cardac falure oc'currng n persons wth angular deformty of the spne. Br J Surg 1930; 18: Jmenez JFM, de Cos Escun JS, Vcente CD, et al. Nasal ntermttent postve pressure ventlaton: analyss of ts wthdrawal. Chest 1995; 107: Use of a Bronchal Blocker to mprove Gas Exchange n Respratory Falure and Dfferental Lung Dsease* Arthur]. Boujoukos, MD, FCCP; Robert]. Keenan, MD, FCCP The use of a bronchal blocker to optmze gas exchange n a patent wth marked dfferental lung dsease s reported. Ths technque proved to be a useful alternatve n an CU settng to ndependent lung ventlaton. (CHEST 1996; 110: ) Key words: bronchal blocker; gas exchange; respratmy falure Abbrevatons: DLET =double-lumen endobronchal tube; ETT =endotracheal tube; LLL=left lower lobe; PEEP=postve end-expratory pressure; SLT=sngle lung transplant ' ~ ~ complcated e n by a dfferental lung pathologc l l condton, respratory falure may be dffcult to manage wth conventonal approaches. n such cases, knowledge of local ventlaton-perfuson ratos and dfferental complances wthn the lungs may be used to talor effectve alternatve strateges. The extremes of dfferental lung pathophysology are frequently encountered n sngle lung transplant (SLT) recpents. SLT recpents wth pulmonary hypertenson exhbt major ventlaton-perfuson msmatch, wth 8.5% or more of the pulmonary perfuson dverted to the allograft by hgh natve pulmonary vascular resstance. 1 n patents wth allograft dysfuncton, ventlatory management conssts of postve end-expratory pressure (PEEP), sedaton, occasonally neuromuscular blockade, and lateral postonng wth the natve lung down. Ths last manpulaton often s essental to mprovng ventlaton-perfuson matchng and oxygenaton. n emphysemc SLT recpents, partcularly those wth *From the Dvson of Crtcal Care Medcne/Department of An-. esthesology and Crtcal Care (Dr. Boujoukos) and Dvson of Cardothoracc Surgery/Department of Surgery (Dr. Keenan), Unversty of Pttsburgh Medcal Center, Pttsburgh. Manuscrpt receved Febmary 8, 1996; revson accepted May allograft dysfuncton, dfferental complance between the emphysematous natve lung and the relatvely noncomplant allograft can result n natve lung hypernflaton, auto-peep, and hypotenson. Emphysemc SLT recpents often need ndependent lung ventlaton wth low PEEP and a ventlatory rate low enough to prevent auto-peep n the natve lung whle mantanng hgher levels of PEEP, smaller tdal volumes, and a hgher rate n the stffer allograft. 2 3 Wth ndependent lung ventlaton, however, bronchal anatomy sometmes precludes an effectve bronchal seal wth a double-lumen endobronchal tube (DLET), and thck pulmonary secretons combned wth the small ntralumnal sze of the DLET make pulmonary tolet extremely dffcult. Ths case report descrbes an SLT recpent wth both end-stage emphysema and pulmonary hypertenson n her remanng natve lung, whose severe allograft dysfuncton was managed usng a bronchal blocker. CASE REPORT A 51-year-old woman, 68 kg n body weght and 1.68 m2 n body surface area, receved a left SLT for end-stage emphysema. Preoperatvely, she also had severe pulmonary hypertenson \vth systolc pulmonary artery pressures of90 mm Hg and a pulmonary vascular resstance ndex of 1,300 dvne s/cm5/m2 (normal: 50 to 220 dyne s/cnhm 2 ). After transplantaton she had a moderate reperfuson njury requrng ndependent lung ventlaton. A bedsde lung perfuson scan performed on the 1st postoperatve day revealed that only 5% of the pulmonary blood flow was drected to the hypertensve natve lung. By the 4th postoperatve day, the Pa02 was 128 mm Hg on an Fo2 of 0.5 and PEEP of.5 em H20. The double-lumen tube was removed, and a 8.5 endotracheal tube (ETT) was placed to facltate clearance of thck brown secretons and promote weanng from mechancal ventlaton. BAL of an atelectatc left lower lobe (LLL) was requred to remove thck brown mucus, and antbotc therapy was begun. Durng the next 4 days, arteral oxygenaton was less stable, wth postonng changes leadng to arteral ox)'gen saturaton of 82 to 85%. The patent requred full sedaton and natve lung-down postonng. An arteral blood gas <malyss revealed a ph value of7.31, a Pa02 level of69 mm Hg, and PaC02 level of 64 mm Hg. Radographcally, there was no progresson of her ntal allograft nfltrate. Thck secretons were agan asprated from the LLL, wth transent mprovement n oxygenaton. Attempts to ncrease PEEP above 7.5 em H20 or reduce the nspraton-expraton rato from 1:4 led to hypernflaton of the natve emphysematous rght lung and subsequent hypotenson and oxygen desaturaton. 'Wth an emprc clagnoss of allograft rejecton, the patent was gven the frst of three daly doses of methylprednsolone (1,000 mg). Although ndependent lung ventlaton and selectve PEEP to the allograft were consdered, the volume and vscosty of the pulmonary secretons were consdered to be a major lmtaton because of the small lumen sze of the double-lumen tube requred. Because natve pulmonary blood flow was thought to be only.5% of total blood flow, t was felt that bronchal blockade could safely lmt natve lung ventlaton and PEEP wthout sgnfcantly ncreasng shunt. A No.6 Fogarty catheter was placed through a nasal tmmpet and past the vocal cords exteror to the endotracheal tube (ETT) wth bronchoscopc gndance. The Fogarty catheter was then postoned nto the rght manstem bronchus, and the balloon was nflated wth ar. Although the balloon was too small to occlude ventlaton to the entre lung, t effectvely blocked the bronchus ntermedus. Oxygenaton and C02 clearance mmedately mproved (Table 1). On two occasons, repostonng for a chest radograph dslodged the bronchal blocker and caused arteral desaturaton. Ths was easly corrected by repostonng the bronchal Selected Reports