FIGURE 1. New device to perform standardized VaIsalva's maneuver. can be easily assembled in the pulmonary laboratory of most hospitals, is easy to carry, and can be used in conjunction with most commercially available sphygmomanometers. Furthermore, the cost of the device is minimal. DESCRIPTION OF TIlE DEVICE

The device consists of four parts (Fig 1). The disposable mouthpiece (Inspiron No. 0012(0) fits into one end of a 6inch corrugated tube (Hudson Corr-A-Tube II, No. 1410). The other end of this tube is coupled to a connector (BardParker oxygen hose connector No. 5(02) via a 22 X 22-mm adapter (Bard-Parker No. 5095). This connector fits snugly onto the male hub of the rubber tubing of most commercially available sphygmomanometers. An 18-gauge needle may be inserted into the adapter to equalize the intraoral and intrabronchial pressures during the strain phase of Valsalva's maneuver.' The patient in the supine or semirecumbent position blows into the mouthpiece and maintains the column of mercury in the sphygmomanometer at 40 mm for a period of ten seconds. This device is presently being studied in a series of patients. Shashi K. Agarwal, M.D., Chief Medical Resident Bergen Pines County Hospital, Paramus, NT REFERENCE')

1 Braunwald E, Oldham HN Jr, Ross J Jr, et al: The circulatory response of patients with idiopathic hypertrophic subaortic stenosis to nitroglycerin and to the Valsalva maneuver. Circulation 29 :422, 1964 2 Barlow JB, Pocock WA, Marchand P, et al: The significance of late systolic murmurs . Am Heart J 66 :443-452, 1963 3 Ewing DJ, CampbelllW, Burt AA, et al: Vascular reflexes in diabetic autonomic neuropathy. Lancet 2:1354-1356, 1973 4 Levin AB: A simple test of cardiac function based upon the heart rate changes induced by Valsalva maneuver. Am J CardioI18:90-99, 1966

Sutureless Prosthesis for Aortic Aneurysms To the Editor:

In 1912, Alexis Carrell described a technique for permanent intubation of the thoracic aorta and suggested its use in treating thoracic aortic aneurysms. In 1952, Voorhees et al 2 reported the use of Vinyon "N" cloth for bridging arterial defects. In several of their laboratory animals, Voorhees et al 2 used a "nonsuture Vitallium cuff technique" described by Blakemore et al 3 in 1942. Since that time, there has been

CHEST, 75: 2, FEBRUARY, 1979

FIGURE 1. Dacron graft with metal rings. One ring is already covered with Dacron felt little interest in a sutureless technique for inserting arterial prostheses. Recently, we developed a prosthesis consisting of Dacron cloth with two cloth-covered stainless steel spools at either end for use in the treatment of thoracic aneurysms (Fig 1). We have now used this prosthesis in six patients, with no surgical deaths and no complications. Follow-up x-ray films and arteriograms have shown no tendency for thrombosis or migration of the prosthesis. The high surgical mortality in acute dissection of the aorta is primarily due to hemorrhage from attempts to suture friable edematous tissue. By utilizing a sutureless prosthesis, this complication is avoided . The prosthesis may be inserted with little difficulty and thus a short duration of cross-clamping of the aorta. We believe that this is a significant advance in the treatment of thoracic aneurysms, and we are preparing to submit a complete report on our work in the near future. Michael D. Strong, M.D. Paschal M. Spagna, M.D., F.C.C.P. and GeraldM. Lemole, M.D., F.C.C.P. Deborah Heart and Lung Center, Browns Milla, NT and Episcopal Hospital, Philadelphia REFERENCE')

1 Carrel A: Results of the permanent intubation of the thoracic aorta. Surg Gynecol Obstet 15:245-248, 1912 2 Voorhees AB, Jaretzki A, Blakemore AH: The use of tubes constructed from Vinyon "N" cloth and bridging arterial defects. Ann Surg 135:332-336,1952 3 Blakemore AH, Lord JW, Stefko PL: The severed primary artery in the war wounded. Surgery 18:488-508, 1952

Unilateral Diaphragmatic Paralysis in Association with Erb's Palsy To the Editor:

Erb's palsy is a well-described complication of trauma to

the shoulder and neclc.1 Except in neonates, it is very unusual

for Erb's palsy to be accompanied by an ipsilateral diaphragmatic paralysis. The purpose of this communication is to

COMMUNiCaTIONS TO THE EDITOR 209

report such a case occurring in an adult following drug overdosage. CASE REPoRT

A 57-year-old white man was brought to the emergency room of UCLA Hospital after having lain for four days on his right side on the floor of his apartment following ingestion of a large dose of meprobamate. The patient was well developed and well nourished. His temperature was 39.2°C ( 102.6°F), the pulse rate was 120 beats per minute, the respiration rate was 40/min, and the blood pressure was 120/70 mm Hg. There was dullness to percussion over the entire right pulmonary field, with decreased and tubular breath sounds. There was marked edema of the right arm. On neurologic examination, significant abnormalities were limited to the right arm. There was no evidence of muscular atrophy or "winging" of the scapula. The rhomboid muscles were intact. The following strengths were noted for various muscles: deltoid muscle, 0/5; adductor muscles of shoulder, 3/5; biceps muscle, 0/5; triceps muscle, 3/5; flexor muscles of wrist, 5/5; and intrinsic musculature of hand, 5/5. Areas of decreased sensation and hyperpathia were present over the right shoulder. Laboratory data included the following: white blood cell count, 9,600/cu mm, with a shift to the left; blood urea nitrogen level, 75 mg!l00 ml; creatinine level, 3.9 mg/100 ml; serum osmolarity, 341 mOsm; creatine phosphokinase level, 2,200 International units/ml; oxygen pressure, 54 mm Hg, carbon dioxide pressure, 28 mm Hg; pH, 7.44; and serum level of meprobamate, 14.1 mg/100 mI. A chest x-ray film showed consolidation of the entire right lung. By the eighth day of hospitalization, infiltrates on the chest x-ray film had cleared considerably, revealing an elevated right hemidiaphragm and an area of atelectasis above the diaphragm ( Fig 1) . Fluoroscopic examination ("sniff test") showed paradoxic motion of the right hemidiaphragm. A chest x-ray film taken two months earlier was normal. Electromyographic studies confirmed the clinical impression of an Erb's palsy of the CS-6 brachial plexus, with sparing of the rhomboid muscles. A study of conduction by the phrenic nerves showed an intact left phrenic nerve, while the right phrenic nerve did not react.

DISCUSSION

Diaphragmatic paralysis should be suspected in patients with persistent physical and roentgenographic findings of atelectasis and unilateral elevation of the diaphragm. The present case is unusual because unilateral diaphragmatic paralysis was associated with an ipsilateral Erb's palsy.2 Neonates born with an ipsilateral Erb's palsy commonly have a unilateral diaphragmatic paralysis.s This syndrome occurs as a complication of delivery in which excessive manipulation of the shoulder and neck is required. It probably results from traction injury to the phrenic nerve and to the upper portion of the brachial plexus. Decreased mobility of the shoulder and neck in adults may account for the fact that this syndrome is so rarely acquired after birth; however, the occurrence in this patient of both hemidiaphragmatic paralysis and an ipsilateral Erb's palsy strongly suggests the same mechanism as has been proposed in neonates, namely, traction on both the brachial plexus and the phrenic nerve. The absence of conduction in the right phrenic nerve supports the contention . We believe that these traction injuries were sustained during the prolonged period when the patient lay comatose on the floor of his apartment in a position which was probably such that his head and neck were forced to the left, while his right shoulder was pushed caudally . In conclusion, we believe that in adults, as well as in neonates, trauma to the shoulder and neck can cause traction injury to both the phrenic nerve and the brachial plexus, resulting in unilateral diaphragmatic paralysis in association with an ipsilateral Erb's palsy. Diaphragmatic motion should therefore be assessed in patients with Erb 's palsy, since such patients may have an unrecognized diaphragmatic paralysis. Michael P. Biberstein, Senior Medical Student and Harvey Eisenberg, M.D. Pulmonary Division, Department of Medicine Center for the Health Sciences University of California, Los Angeles Reprint requests: Dr. Eisenberg, Pulmonary Section, Room 1409, Metropolitan Hospital Center, 1901 First Ave, New York 10029 REFERENCES

1 Leffert RD: Brachial-plexus injuries. N Engl J Med 291: 1059-1069, 1974 2 Stevens J: Brachial plexus paralysis. In Cogman EA (ed) : The Shoulder. Boston, private publisher, 1934, pp 332399 3 Richard J, Chevalier V, Capelle R, et al: La paralysie diaphragmatique obstericale. Arch Fr Pediatr 14:563-598, 1957

Cardiac Entrapment by Thymoma following Coronary Bypass Surgery To the Editor: We present the findings in what is apparently the first reported case of entrapment of the heart by a thymoma following cardiac surgery. CASE REPoRT

FlGUBE 1. Chest x-ray film showing area of atelectasis above elevated hemidiaphragm.

210 COMIlUNICAnONS TO THE EDITOR

A 53-year-old white man underwent an uneventful coronary bypass procedure on May 4, 1976. Autogenous sections

CHEST, 75: 2, FEBRUARY, 1979