Preflight Assessment by Hypoxic Inhalation Test in Cardio-Pulmonary Patients 

J. Lebzelter, G. Fink, E. Kleinman, I. Rosenberg, M.R. Kramer

Pulmonology Institute, Rabin Medical Center, Beilinson Campus, Petah Tikva

Flying may expose passengers to hypoxic conditions, which may induce hypoxemia, particularly in those with chronic heart and/or lung disease. Onset of dyspnea, wheezing, chest pain, cyanosis and right heart failure can lead to urgent need for oxygen during flight. The hypoxia inhalation test (HIT) provides a safe and simple means of identifying those who may develop hypoxemia during flight.

We report our experience with 48 self-reporting patients who underwent HIT prior to pre-planned air travel. They inhaled for 15-minute periods a reduced oxygen concentration (F₁O₂ 15%) under normobaric conditions, during which O₂ saturation was monitored by pulse oximeter; electrocardiogram, blood pressure and symptoms were also monitored. O₂ saturation of 85% (PaO₂ 50 mm Hg) was considered a positive test. In the 8 cases (17%) with a positive test, 5 had chronic obstructive pulmonary disease and 3 had cardiovascular and/or combined heart-lung disease.

We calculated predicted O₂ partial pressure in altitude (PaO₂ ALT) and compared it to actual results in the 8 patients with a positive HIT. In 5, use of the predicted formula would have under-diagnosed the hypoxemia that developed during the HIT. Thus, the results of the HIT changed treatment strategy in these patients. We recommend that patients with positive tests use O₂ (2LPM or 4LPM) during flight.

HIT is practical and of potential benefit in the objective assessment of patients with various degrees of heart, lung or combined heart-lung disease. Clinicians should be aware of the relative risk of hypoxia during flight in such patients, and of the value of HIT in identifying them, leading to increase in its use.

High Dose Endobronchial Brachy - Therapy for Malignant Airway Obstruction

Alex Yarmolovsky, Alan Katz, Eyal Fenig, G. Fink, Daniel Bendayan, Aaron Sulkes, Mordechai R. Kramer

Institutes of Pulmonology and Oncology, Rabin Medical Center, Beilinson Campus, Petah Tikva, and Sackler Faculty of Medicine, Tel Aviv University

Brachytherapy is especially suitable for palliative treatment of endobronchial tumors adjacent to internal organs that might be damaged by intensive external beam radiation, but are easily accessed with a flexible bronchoscope. This treatment is mostly palliative.

30 patients underwent such palliative high-dose endobronchial brachytherapy to alleviate malignant airway obstruction. With the aid of a flexible fiberoptic bronchoscope an endobronchial catheter was inserted adjacent to the tumor and treatment delivered using a 192Ir remote afterloader for 5-10 min, in 2 or 3 sessions.

There was symptomatic improvement in 26 (86%) and objective improvement in 27 (90%). 1 patient died of hemoptysis.

Therapeutic and Toxic Theophylline Levels in Asthma Attacks

Aliza Zeidman, Joseph Gardyn, Zinaida Fradin, Gershon Fink, Moshe Mittelman

Dept. of Medicine B, Rabin Medical Center, Golda (Hasharon) Campus and Pulmonary Institute, Rabin Medical Center, Beilinson Campus, Petah Tikva; and Sackler Faculty of Medicine, Tel Aviv University

Although first-line therapy for bronchial asthma has changed over the past decade to anti-inflammatory medication such as inhaled corticosteroids and cromolyn with possible addition of beta-agonists, theophylline is still useful and therefor widely used. However, several studies have raised serious questions regarding its efficacy in acute asthmatic exacerbations. These studies, the narrow therapeutic range of the drug, the frequency of side effects and interactions with common drugs, and individual variation in clearance and metabolism, have prompted its reevaluation in the management of asthma. Therapeutic serum levels of theophylline are between 10 to 20 mcg/ml. Most adults achieve these concentrations with daily slow-release oral theophylline preparations, 200-400 mg (approximately 10 mg/Kg) twice a day. However, when such a patient presents to the emergency room (ER) in an asthmatic attack, immediate intravenous theophylline is often given, regardless of maintenance treatment. Since the rationale for this common therapeutic approach has been challenged, the current study was undertaken. Serum theophylline levels were measured in 23 consecutive asthmatics presenting to the ER in an acute attack. 15 (68%) had therapeutic levels (above 10 mcg/ml) and 2 had toxic levels (above 20 mcg/ml), prior to receiving the standard intravenous theophylline dose given for an attack. These data indicate that most patients with bronchial asthma on oral maintenance theophylline do not require additional intravenous theophylline when in an attack. It probably will not benefit them and may even induce serious theophylline toxicity.