Acute Respiratory Compromise Resulting from Tracheal Mucous Impaction Secondary to a Transtracheal Oxygen Catheter

close confines of an urban prison. Our attempts to assess the health of other inmates and to evaluate potential sources of infection at the Justice Center were unsuccessful. Blastomycosis may take a variety of clinical forms, including silent asymptomatic infection, an acute primary pneumonia that may resolve spontaneously, or as a chronic slowly progressive disease, occasionally leading to dissemination. Although a rapidly progressive and fulminant form has been described, there are relatively few reports of acute disseminated miliary blastomycosis progressing to respiratory failure.P.... ll Shaw et all reported eight patients in Mississippi with miliary blastomycosis who experienced extremely rapid clinical deterioration, resulting in high mortality. Griffith and Campbell" described a case of acute miliary blastomycosis presenting as fulminant respiratory failure in a Mississippi fanner. The described case, therefore, is notable for two reasons: first, the illness in this patient occurred in a metropolitan area and in the absence of any history of exposure to a rural setting or urban environmental source; second, our patient presented with rapidly progressive disseminated miliary blastomycosis leading to respiratory failure, a rarely reported complication of the disease. Most of the reported cases of acute miliary blastomycosis with respiratory failure occurred in patients exposed to rural areas or who resided in Mississippi, an area known to have an extremely high incidence ofblastomycosis. 11 Despite the absence of a history of exposure to a rural or urban source of infection, consideration should still be given to the diagnosis of blastomycosis, especially in the presence of miliary disease, as this form of the infection may progress rapidly to respiratory failure. REFERENCES

1 Steck W Blastomycosis. Dermatol Clin 1989; 7:241-50 2 Shaw GB, Campbell GO, Busey JF. Miliary blastomycosis. Am Rev Respir Dis 1976; 113:81 3 Klein BS, Vergeront JM, Weeks RJ, Kumar UN, Mathai G, Varkey B, et aI. Isolation of Blastomyces dermatitidis in soil associated with a large outbreak of blastomycosis in Wisconsin. N Engl J Med 1986; 314:529-34 4 Armstrong C~ Jenkins SR, Kaufman L, Kerkering TM, Rouse BS, Miller GB Jr. Common-source outbreak of blastomycosis in hunters and their dogs. J Infect Dis 1987; 155:568-70 5 Cockerill FR III, Roberts GO, Rosenblatt JE, Vtz J~ Vtz DC. Epidemic of pulmonary blastomycosis (Namekagon fever) in Wisconsin canoeists. Chest 1984; 86:688-92 6 Tosh FE, Hammerman KJ, Weeks RJ, Sarosi GA. A common source epidemic of North American blastomycosis. Am Rev Respir Dis 1974; 109:525-29 7 Blastomycosis-North Carolina. MMWR 1976; 25:205-06 8 Kitchen MS, Reiber CD, Eastin GB. An urban epidemic of North American blastomycosis. Am Rev Respir Dis 1977; 115:1063-66 9 Stelling CB, Woodring JH, Rehm SR, Hopper D~ Noble RC. Miliary pulmonary blastomycosis. Radiology 1984; 150:7-13 10 Brown LR, Swensen SJ, Van Gray RE, Prakash UBS, Coles DT, Colby ~ Roentgenologic features of pulmonary blastomycosis. Mayo Clin Proc 1991; 66:29-38 11 Griffith JE, Campbell GO. Acute miliary blastomycosis presenting as fulminating respiratory failure. Chest 1979; 75:63032

Acute Respiratory Compromise Resulting from Tracheal Mucous Impaction secondary to a Transtracheal Oxygen C8theter* Bernard]. Roth, M.D., F.C.C.R; Thomas W lroine, M.D., F.C.C.R; Douglas A. Liening, AI.D.;

Newton

a

Duncan, M.D.; and W Hal Cragun, M.D., F.C.C.R

Transtracheal oxygen catheters are being increasingly used because of savings in oxygen usage and patient preference. The complications of the catheter are believed to be minor and easily managed. Inspissated mucous collections that form at the tip of the SCOOP 1 (Transtracheal Systems, Denver, Colorado) catheter have been reported but are usually easily expectorated by the patient. This report describes a patient who had development of acute respiratory compromise from crusted mucoid impaction of the trachea secondary to transtracheal catheter use. General anesthesia and rigid bronchoscopy were required for removal of the obstructing impaction. Unexplained worsening of respiratory symptoms in patients with transtracheal oxygen catheters should be addressed by prompt stripping of the catheter. (Che.t 1992; 101:1465-66) he use of a transtracheal oxygen catheter to administer T oxygen to patients with hypoxemia has become more

popular. Numerous publications have shown that the oxygen requirement (and therefore cost) is reduced by the use of the transtracheal catheter when compared with the nasal cannula.':" Patients prefer the transtracheal catheters because they are aesthetically superior to nasal cannulas, noninjurious to nasal mucosa, and subjectively improve dyspnea. 1·10 The complications of the transtracheal catheter are believed to be minimal and easily managed.v" Although large inspissated mucous collections adherent to the tip of the catheter are usually removed easily by pulling out the catheter and having the patient expectorate the so-called "mucous ball" (catheter stripping), respiratory failure and death have been reported from tracheal obstruction.t"" In this report, we describe a patient using transtracheal oxygen who had development of acute respiratory compromise from mucoid impaction of the trachea that required general anesthesia and rigid bronchoscopy for removal. CASE REPORT

A 69-year-old woman with a clinical diagnosis of idiopathic pulmonary fibrosis did not respond to treatment with high-dose prednisone and azathioprine and required more than 6 L of oxygen by nasal cannula to maintain her arterial oxygen saturation above 90 percent during a short walk. Her pulmonary function tests revealed a severe restrictive defect with normal Rows (FEV I> 1 L). A transtracheal oxygen catheter was recommended to decrease the oxygen requirement and perhaps improve her sensation of dyspnea. A SCOOP (Transtracheal Systems, Denver) transtracheal stent was placed using the techniques described in the Institute for ·From the Pulmonary Disease/Critical Care Service (Drs. Roth, Irvine, and Cragun), and the Otolaryngology-Head and Neck Surgery Service (Drs. Liening and Duncan), Madigan Army Medical Center, Tacoma, WA. The opinions expressed are those of the authors and are not to he construed as official or as reflecting the views of the Department of the Army or the Department of Defense. CHEST I 101 I 5 I MA"f, 1992

1485

Transtracheal Oxygen Therapy (ITaf) Manual. Seven days later, the stent was replaced with a SCOOP-I catheter; 6 Umin flow through the SCOOP catheter was required to maintain oxygen saturation at greater than 90 percent with exercise. The oxygen saturation was 94 percent at rest on 2 Umin. A humidifier for the oxygen was not used. For the next two days, the patient felt subjectively better and was very active. Three days after SCOOP-I placement, she was seen in an emergency department complaining of increasing nonproductive cough. A chest roentgenogram showed good catheter placement and she was treated with trimethoprim-sulfamethoxazole for presumed bronchitis. Six days after SCOOP-I placement, the patient presented complaining of hoarseness, general malaise, increasing dyspnea, and inability to produce sputum. A small amount of purulent drainage was noted around the catheter insertion site without erythema. A repeated chest roentgenogram was unchanged from previous examinations. The patient was hospitalized and treated with intravenous cephradine for presumed tracheobronchitis. Over the next 24 h, she had increasing respiratory distress with a persistent respiratory rate greater than 40 breaths/min. She developed a subjective sensation of fatigue associated with an increase in the PaC02 from 30 to 42 mm Hg and a decrease in the pH from 7.49 to 7.38. Because of her hoarseness and the development of stridor, flexible nasolaryngoscopy was performed. Large obstructing crusts were noted to be almost filling the subglottic space with extension to the supraglottic area. The patient was emergently brought to the operating room where she had acute total obstruction of her airway during mask inhalation induction and application of laryngeal anesthesia. A rigid ventilating bronchoscope was forced through the obstructing crusts; this quickly established an adequate airway.Through a slow process of repeated suction, irrigation, and foreign body forceps use, the extremely adherent crusts were removed. The transtracheal catheter was also removed and the tracheal mucosa was noted to be free of ulceration. Microscopic evaluation of the obstructing crusts revealed layers of mucin and in8ammatory cells compatible with a mucolith. The patient required reintubation 48 h after surgery for worsening respiratory distress. No obstruction was noted at the time of intubation; however, copious secretions were suctioned via the endotracheal tube. She was extubated 24 h later but over the next five days had worsening oxygenation with increasing diffuse infiltrates on chest roentgenogram. A repeated 8exible bronchoscopy was normal. The patient elected to have no further lifesaving measures and died 22 days after the initial placement of the SCOOP stent in respiratory failure. Postmortem examinationn revealed endstage usual interstitial pneumonitis and normal trachea. DISCUSSION

This is the third report of acute respiratory compromise secondary to "mucous ball" obstruction of the trachea with transtracheal oxygen catheter use. 10.11 The patient from the Cleveland Clinic series had resolution of respiratory distress after bronchoscopic removal of the mucolith while the patient whose case was reported by Burton et al" died of suffocation and the mucous ball was found at autopsy 10,11 Since these mucous balls are not visible on the chest roentgenogram, bronchoscopy may be necessary for diagnosis and treatment. 10-12 Mucous collections appear to be a problem during the use of the SCOOP-l catheter which is not removed while the tract is maturing.3.9.11.13 Inspissated mucous combined with inflammatory protein secretions from the tracheal wall comprise the mucolith or mucous ball. Small, forming mucous balls are probably stripped offthe SCOO P-2catheter which is removed twice daily for cleaning. The largest review of experience with the Transtracheal Systems catheter (100 1466

patients) reported a 10 percent incidence of mucous balls during use of SCOOF-I. 3 Other risk factors for mucous ball formation are copious secretions, high-How oxygen, lack of humidification, poor cleaning technique, and inadequate cough due to poor pulmonary mechanics," However, a patient has had development of a significant obstructing mucolith while using SCOOF-2 with 6 Umin oxygen How despite a humidifier and good cleaning technique." Our patient was at moderate risk for mucous ball formation due to 2 Umin oxygen flow at rest and a low risk assessment score." The SCOOP Transtracheal Oxygen Therapy Clinicians Guide (not available to us at the time this patient was treated) recommends humidification for flows greater than 1 Umin and at least weekly stripping of the SCOOF-l catheter by the physician. 14 This report emphasizes that new pulmonary symptoms such as hoarseness, stridor, change in cough, or increasing dyspnea during the use of a transtracheal oxygen catheter should warn the physician about the possibility of impacted crusted, tracheal mucous that may lead to acute total airway occlusion and respiratory compromise. Catheter stripping and/or urgent bronchoscopy may be necessary for diagnosis and treatment. REFERENCES

1 Heimlich HJ. Respiratory rehabilitation with transtracheal oxygen system. Ann Otol Rhinol LaryngoI1982; 91:643-47 2 Heimlich HJ, Carr CC. Transtracheal catheter technique for pulmonary rehabilitation. Ann Otol Rhinol Laryngoll985; 94:502 3 Christopher KL, Spofford BT, Petrun MD, McCarty DC, Goodman JR, Petty TL. A program for transtracheal oxygen delivery: assessment of safety and efficacy. Ann Intern Med 1987; 107:802-08 4 Heimlich HJ, Carr CC. The micro-trach: a seven year experience with transtracheal oxygen therapy. Chest 1989; 95:1008-12 5 Bloom BS, Daniel JM, Wiseman M, Knorr RS, Cebul R, Kissick WL. Transtracheal oxygen delivery and patients with chronic obstructive pulmonary disease. Respir Med 1989; 83:281-88 6 Banner NR, Govan JR. Long term transtracheal oxygen delivery through micro catheter in patients with hypoxemia due to chronic obstructive airways disease. Dr Med J Clin Res 1986; 293:111-14 7 Hoffman LA, Dauber JH, Ferson PF, Openbrier DR, Zullo TG. Patient response to transtracheal oxygen delivery. Am Rev Respir Dis 1987; 135:153-56 8 Wesmiller S~ Hoffman LA, Sciurba FC, Ferson PF, Johnson JT, Dauber JH. Exercise tolerance during nasal cannula and transtracheal oxygen delivery. Am Rev Respir Dis 1990; 141: 789-91 9 Spofford B, Christopher K. The ITOT manual for transtracheal oxygen therapy. 1st ed. Denver: The Institute for Transtracheal Oxygen Therapy, 1986 10 Adano J~ Mehta AC, Stelmach K, Meeker D, Rice T, Stoller JK. The Cleveland Clinic's initial experience with transtracheal oxygen therapy. Respir Care 1990; 35:153-60 11 Burton G, Wagshul FA, Kime w Henderson D. Fatal mucus ball obstruction of the central airway in a transtracheal oxygen therapy patient. Respir Care 1990; 35:1143 12 Haiggi J, Anderhub H~ Kronauer C, Russi EW Transtracheal oxygen administration in long-term oxygen therapy. Schweiz Med Wochenschr 1988; 118:1321-24 13 Fletcher EC, Nickeson D, Costarangos-Galarza C. Endotracheal mass resulting from a transtracheal oxygen catheter. Chest 1988; 93:438-39 14 SCOOP: Transtracheal oxygen therapy clinician guide. Englewood, CO: Transtracheal Systems, 1990 Acute RespiratoryCompromise (Roth st 81)