Biomedical subjects

L Klemka

Publications and source records attributed to L Klemka.

5 recordsLinked to original sources

PubMed1985

Respiratory insufficiency in newborns with abdominal wall defects.

Respiratory failure in newborns with abdominal wall defects has been attributed to increased intra-abdominal pressure and elevation of the diaphragm after closure. Despite surgical techniques designed to minimize intra-abdominal pressure, we have observed prolonged respiratory insufficiency in several such infants. We reviewed the charts of 108 infants from 1975 to 1982 who had abdominal wall defects: 53 with gastroschisis, 29 with small omphaloceles, 22 with liver-containing or giant omphaloceles (GO), and four with cloacal exstrophy. Nine infants with GO (41%) had prolonged respiratory insufficiency and five died. Infants with GO required longer periods of oxygenation and ventilation (P less than .001, ANOVA) than infants with other abdominal wall defects. Clinical observation suggested that infants with GO have a small, narrow thorax. We obtained detailed measurements from the chest radiographs of infants in all groups. After correction for birth weight, babies with GO had smaller chest widths (P less than .001) and lung areas (P less than .05) than infants with other abdominal wall defects. At autopsy, one newborn with GO was found to have severe pulmonary hypoplasia. Prolonged respiratory insufficiency in infants with GO may be explained by pulmonary hypoplasia and/or by a narrow chest deformity which limits lung expansion.

Abdominal Muscles↗

PubMed1985

Effects of almitrine on hypoglossal and phrenic electroneurograms.

Almitrine increases breathing by stimulating peripheral chemoreceptors. Previous studies suggest clinical usefulness in the adult with chronic obstructive pulmonary disease, but little data are available to decide whether almitrine would be helpful in diseases involving pharyngeal airway obstruction, such as apnea of prematurity or obstructive sleep apnea. We investigated the effect of intravenous almitrine on hypoglossal (HG), an upper airway nerve, and phrenic (PHR) neural activity in eight alpha-chloralose-urethan anesthetized, paralyzed, vagotomized, and artificially ventilated cats. Recordings were made of raw and integrated HG and PHR electroneurograms (ENGs), alveolar PCO2, arterial PO2, arterial blood pressure, and rectal temperature. A dose-response study of cumulative almitrine doses ranging from 0.1 to 4.0 mg/kg was performed in three cats. The interactive effects of almitrine and hypoxic stimulation were investigated in four cats. The interactive effects of almitrine and hypercapnic stimulation were investigated in five cats. The interactive effects of almitrine and ventilatory timing were investigated in six cats. We found that 1) almitrine doses as low as 0.1 mg/kg iv increased both HG and PHR ENG activity, with a maximum effect at approximately 1.0 mg/kg; 2) almitrine markedly increased HG and PHR ENG activity at all arterial PO2 values from 35-175 Torr; 3) almitrine increased HG and PHR ENG activity at all arterial PCO2 values from 30-70 Torr; and 4) almitrine increased the ratio of tidal volume to inspiratory time and decreased the inspiratory muscle duty cycle at normoxia and eucapnia.

Airway Obstruction↗

PubMed1985

Day-to-day pneumogram variability.

To determine day-to-day variability in respiratory pattern, we obtained 188 comparisons of pneumograms performed during two successive 24-h intervals. The respiratory pattern values calculated were total duration of brief apnea (apnea density), periodic breathing episodes, longest apnea, number of apneas greater than 11 s, and number of apneas greater than 15 s. For day 1 values for apnea density, periodic breathing, and longest apnea which were within the 90th percentile for normal infants at age 1 month, day 2 values fell outside that range in 4.3, 3.5, and 18% of comparisons, respectively. There was a systematic tendency for the day 2 values to be less than the day 1 values. For each parameter, the day 2 range was lower, the slope of the day 2 versus day 1 regression line was significantly less than 1 (p less than 0.01) and the y-intercept was significantly greater than zero (p less than 0.01). Knowledge of day-to-day pneumogram variability should be helpful in interpreting individual pneumogram results and in assessing the clinical usefulness of pneumogram recordings.

Apnea↗

PubMed1984

A diagnostic approach to suspected obstructive sleep apnea in children.

Most children with obstructive sleep apnea will benefit from tonsillectomy and adenoidectomy. Although polygraphic monitoring remains the definitive diagnostic technique, we wondered if all children suspected of having OSA require such evaluation. We therefore administered a standardized questionnaire to the parents of 23 children with polygraphically proved OSA related to adenotonsillar hypertrophy, 46 age- and sex-matched normal children, and 23 children subsequently referred because of possible OSA. Significantly increased frequencies of the following symptoms were found in the OSA group compared with the control group: difficulty breathing during sleep, 96% vs 2%; apnea observed by the parents, 78% vs 5%; snoring, 96% vs 9%; restless sleep, 78% vs 23%; chronic rhinorrhea, 61% vs 11%; and mouth breathing when awake, 87% vs 18%. Using discriminant analysis, an OSA score was derived that correctly classified all control subjects and 22 of 23 patients with OSA. Considering the data from all groups, we found that (1) OSA scores greater than 3.5 were highly predictive of OSA requiring adenotonsillectomy; (2) no child with an OSA score less than -1 had OSA; and (3) in children with OSA scores between -1 and 3.5, polygraphic monitoring was required to determine the severity of sleep-related airway obstruction and the need for surgical treatment. Use of the OSA score should decrease the need for polygraphic monitoring and facilitate selection of children for tonsillectomy and adenoidectomy.

Adenoids↗

PubMedDate not supplied

Liposyn infusion increases plasma prostaglandin concentrations.

To determine whether Liposyn infusion results in increased plasma prostaglandin (PG) concentrations, the following study was performed in 33 adult rabbits with chronically implanted arterial and venous catheters. Plasma PG concentrations were determined by radioimmunoassay for two vasodilators, PGE2 and PGI2 (as measured by its metabolite 6-keto-PGF1 alpha), and two vasoconstrictors, thromboxane (TX) A2 and PGF2 alpha, as measured by their metabolites TXB2 and PGF2 alpha-M, respectively. A 1-hour infusion of Liposyn at 4 ml per kg resulted in statistically significant increases in arterial and venous concentrations of PGE2 and 6-keto-PGF1 alpha (p less than 0.001) and of TXB2 (p less than 0.04). There were no significant changes in PGF2 alpha-M plasma concentrations. Liposyn infusion also resulted in a small but statistically significant increase in PaO2 of 4.7 +/- 1.5 torr (p less than 0.01). It is concluded that Liposyn infusion results in statistically significant increases in plasma concentrations of PGE2, 6-keto-PGF1 alpha, and TXB2.

6-Ketoprostaglandin F1 alpha↗