Ernest K. Cotton

Carbenicillin and gentamicin: Pharmacologic studies in patients with cystic fibrosis and pseudomonas pulmonary infections

Fourteen treatment courses with carbenicillin, 100 to 600 mg. per kilogram every 4 hours, gentamicin, 4–5 mg. per kilogram per day, or a combination of these drugs were given to patients with cystic fibrosis, who had extensive pulmonary disease and Pseudomonas aeruginosa colonization, to determine the penetration of these antibiotics into sputum, to attempt to eradicate pseudomonas organisms from sputum, and to observe the clinical effects of such intensive chemotherapy. The mean minimum inhibiting concentration (MIC) of carbenicillin for 27 pseudomonas strains was 85.6 μg per milliliter. The mean peak serum level of carbenicillin at 600 mg. per kilogram every 4 hours was 2,176 μg per milliliter at 15 minutes; the mean peak sputum level was 78 μg per milliliter at 60 minutes. Peak serum levels at 100 to 400 mg. per kilogram every 4 hours ranged from 248 to 464 μg per milliliter with sputum peaks of 0 to 18.4 μg per milliliter. Sputum concentrations of carbenicillin and gentamicin, alone or in combination, were inadequate to eradicate pseudomonas organisms. There was no objective evidence of improvement as a result of chemotherapy in this small group of patients.

Removal of foreign bodies from the tracheobronchial tree.

Abstract With a 5-yr period, 82 infants and children were seen with confirmed foreign body aspiration. Seventy-five of them underwent bronchoscopy for removal of the foreign body. There was no correlation between duration of symptoms and hospitalization, and patients who had aspirated peanuts required no longer hospital stay than those who aspirated other vegetable or nonvegetable matter. Comparison of these results with a similar series treated primarily with postural drainage indicates that a 24-hr trial of this therapy will clear the airway in about 80% of children.

Partial obstruction of endotracheal tubes in children: incidence, etiology, significance.

: We examined 99 endotracheal tubes removed from 81 pediatric patients to determine the incidence of partial endotracheal tube obstruction and predisposing factors. The overall incidence of obstruction was 20.2% (20/99); 14 of the 20 obstructed tubes were occluded less than 50%. General anesthesia during the period of intubation was the only factor significantly associated with an increased incidence of obstruction (p less than 0.05). There was no correlation of obstruction with duration of intubation, the presence of a Murphy-eye side hole, or small tube size. Among the 71 tubes from patients who received general anesthesia, a tube size of 4 mm or less was associated with an increased incidence of obstruction (p less than 0.05). Pressure-flow curves for three different sizes of endotracheal tubes were constructed to determine the increase in resistance produced by different degrees of obstruction. At flow rates that approximated those found in children during quiet breathing, the resistance of tubes that were 50% obstructed was 4 times greater than that found in unobstructed tubes.

Removal of Aspirated Foreign Bodies by Inhalation and Postural Drainage: A Survey of 24 Cases

This survey of patient compliance with drug administration reveals that approximately 25 per cent of those seen in the clinic or in hospitals will not be taking drugs as directed. Compliance failures seem to be directly related to the number of drugs taken daily. Few other etiologic factors have been identified. It is difficult for physicians to ascertain which patients have defected from a therapeutic program, yet these defections may lead to false impressions of drug failure. Assessment of compliance can be aided by chemical testing of urine and blood for presence of drug or markers such as riboflavin. Pill counting and patient interviews are not necessarily sensitive indices of compliance. Although not much data are available on the reasons behind compliance failure, intervention which involves supervision and monitoring of patients has increased adherence to a drug regimen. Some of the measures for strengthening compliance are too expensive to be widely applicable, especially in patients with a chronic disease such as epilepsy. Studies using multifactorial analysis of psychologic, social, environmental, and other parameters are needed to develop technics to ensure better compliance in most patients requiring pharmacologic agents.

Treatment of Status Asthmaticus and Respiratory Failure

Mortality from status asthmaticus is very significant; however, over the past 6 years treatment has been developed which has lowered the number of deaths. This therapy consists of oxygen, fluids, bronchodilators, steroids, physical therapy, isoproterenol, and mechanical ventilation.

Endotracheal Foreign Bodies Difficulties in Diagnosis

The diagnosis of foreign body aspiration into the lower airway depends primarily on the radiographic demonstration of partial bronchial obstruc tion causing localized air trapping or atelectasis, present in 95 per cent of the cases. Èndotracheal foreign bodies may often be visualized directly on high kilovoltage radiographs of the airway or by fluoroscopy. In three of the four cases presented in this report, radiologic evaluation was normal, but endo tracheal foreign bodies were subsequently demonstrated endoscopically. Foreign objects may remain in the trachea for prolonged periods of time, causing persistent coughing, wheezing, or stridor. When there is a clear history or strong suspicion of foreign body aspiration in a patient with persistent symptoms, bronchoscopy should be used for diagnosis and treatment.

The effect of intermittent positive-pressure breathing on airway resistance in normal and asthmatic children

Abstract The airway resistance of 20 children with chronic asthma and 8 normal children was measured before and after intermittent positive-pressure breathing (IPPB) and nebulizer treatments. There was a significant increase in airway resistance in both groups of children following IPPB. No significant increase in resistance was found following the nebulizer treatment. It is concluded that the delivery of air under pressure to the airway can act as an irritant, especially in individuals with asthma.

The use of humidity in asthmatic children

Controversy exists as to the advisability of mist therapy in pulmonary disease. We studied the effects of several forms of humidity on asthmatic airways. Thirty-four children were tested over a period of 8 months as follows: (1) mist with a mean particle size of 3 mu was delivered for 30 min by an ultrasonic nebulizer to 11 children individually in a plastic tent; (2) to another 11 subjects in a tent, mist with a mean particle size of 10 mu was delivered by a jet nebulizer for 30 min;3) 15 patients in a croup room recieved for 30 min water droplets ranging from a microscopic fog to large rain particles (mean 16 mu) generated by a Melco natural fog generator; (4) 10 children were challenged with 3 solutions used commonly for the production of mist: distilled water, half-normal saline, and normal saline. Pulmonary functions were studied on each patient pre- and post-mist exposure. Approximately two thirds of the patients had a significant response, either improvement or deterioration, when challenged with the various forms of mist. No particular group trends were produced either by increasing the mean particle size of humidity, or by using solutions of increasing salinity.

Removal of Aspirated Foreign Bodies by Inhalation and Postural Drainage

From the Departments of Pediatrics, Radiology and Surgery, The Unversity of Colorado Medical Center. 4200 East Ninth Avenue, Denver, Colo. 80220. FOR THE past four years, we have been using a nonendoscopic technic (postural drainage) for removal of the foreign bodies aspirated into the lungs of children. This technic was developed from the methods used to remove thickened secretions from infants and

Partial Obstruction of Endotracheal Tubes in Children. Incidence, Etiology, Significance

We examined 99 endotracheal tubes removed from 81 pediatric patients to determine the incidence of partial endotracheal tube obstruction and predisposing factors. The overall incidence of obstruction was 20.2% (20/99); 14 of the 20 obstructed tubes were occluded less than 50%. General anesthesia during the period of intubation was the only factor significantly associated with an increased incidence of obstruction (p less than 0.05). There was no correlation of obstruction with duration of intubation, the presence of a Murphy-eye side hole, or small tube size. Among the 71 tubes from patients who received general anesthesia, a tube size of 4 mm or less was associated with an increased incidence of obstruction (p less than 0.05). Pressure-flow curves for three different sizes of endotracheal tubes were constructed to determine the increase in resistance produced by different degrees of obstruction. At flow rates that approximated those found in children during quiet breathing, the resistance of tubes that were 50% obstructed was 4 times greater than that found in unobstructed tubes.