Estudio piloto de marcadores inflamatorios en el sindrome de apnea obstructiva del sueño / Pilot study of inflammatory markers in the syndrome of obstructive sleep apnea

El síndrome de Apnea Obstructiva del Sueño (SAOS), consiste en la aparición repetida de episodios de obstrucción faríngea durante el sueño como consecuencia de un colapso de la vía respiratoria. La respuesta fisiológica a la hipoxia intermitente crónica es la generación de una respuesta inflamatoria local y sistémica. Se han evidenciado cambios importantes a nivel cardiovascular en pacientes con SAOS; sin embargo, se desconocen cuáles marcadores séricos y genéticos pudieran ser de utilidad. En el presente estudio, se presentan 15 marcadores séricos y 3 genéticos (IL-6, IL-1β y TNF-α) en un grupo de cinco pacientes para determinar cuáles pueden ser los marcadores de interés en la aparición y en el desarrollo de esta patología respiratoria. Se proponen como marcadores los niveles séricos: proteína C reactiva, TNFα, IL-6, el receptor soluble de TNF I, sCD62, sCD154, nitrotirosina y anti-oxLDL. Los niveles de IL-1 β, el receptor de TNF soluble II, sCD25, sCD54, nitritos y nitratos no parecieran ser buenos marcadores en SAOS. Los estudios genéticos no fueron concluyentes.

Obstructive sleep apnea syndrome (OSAS) is a repeated sequences of pharynx obstruction during sleep as a consequence of airway collapse. The physiological response to the desaturation is the generation of a local and systemic inflammatory immune response. Important changes at cardiovascular levels in patients with OSAS have been observed; however, it is not know which serum or genetic parameters could be useful. In the present study, we present 15 serum and 3 genetic (IL-6, IL-1β y TNF-α) markers in a group of five patients in order to determine which marker could be useful to study the genesis and progression of this respiratory pathology. The proposed serum markers are C reactive proteín, TNFα, IL-6, soluble de TNF receptor I, sCD62, sCD154, nitrotirosine and anti-oxLDL. The levels of IL-1 β, soluble TNF receptor II, sCD25, sCD54, nitrite y nitrate do not seem to be good markers for OSAS. The genetic studies were not conclusive.

Ghrelin, leptin, adiponectin, and resistin levels in sleep apnea syndrome: role of obesity

The aim of this study was to investigate the relationship among plasma leptin, ghrelin, adiponectin, resistin levels, and obstructive sleep apnea syndrome [OSAS]. Fifty-five consecutive newly diagnosed OSAS patients and 15 age-matched nonapneic controls were enrolled in this study. After sleep study between 8:00 AM and 9:00 AM on the morning, venous blood was obtained in the fasting state to measure ghrelin and adipokines. Serum ghrelin levels of OSAS group were significantly [P<0.05] higher than those of the control group. No significant difference was noted in the levels of leptin, adiponectin, and resistin in OSAS group when compared to controls. There was a significant positive correlation between ghrelin and apnea-hypopnea index [AHI] [r=0.237, P<0.05] or the Epworth sleepiness scale [ESS] [r=0.28, P<0.05]. There was also a significant positive correlation between leptin and body mass index [r=0.592, P<0.0001]. No significant correlation was observed between leptin, adiponectin, resistin, and any polysomnographic parameters. Our findings demonstrated that serum ghrelin levels were higher in OSAS patients than those of control group and correlated with AHI and ESS. Further studies are needed to clarify the complex relation among OSAS, obesity, adipokines, and ghrelin

Predictors of nocturnal oxygen desaturation in chronic obstructive pulmonary disease in a South Indian population.

CONTEXT: Nocturnal Oxygen Desaturation (NOD) in patients with chronic obstructive pulmonary disease (COPD) is associated with a poor prognosis. AIMS: To document the occurrence of NOD in COPD and to identify factors which might predict NOD in COPD patients with daytime arterial oxygen tension (PaO2) > or =60 mm Hg. SETTINGS AND DESIGN: This prospective study was conducted in patients attending the special respiratory clinics or admitted in JIPMER, Pondicherry. METHODS AND MATERIAL: Thirty consecutive patients with COPD were divided into two groups, desaturators and non-desaturators on the basis of nocturnal oxygen saturation. Statistical analysis used: Unpaired 't' test, Karl Pearson's correlation equation and stepwise multiple regression analysis was done. RESULTS: Fourteen patients (46.6%) experienced NOD. Desaturators had lower awake oxygen saturation, PaO2, forced vital capacity, forced expiratory volume in one second and peak expiratory flow rate. There was positive correlation between nocturnal O2 saturation and PaO2 (r=0.638 and P value =0.014) and awake SPO2 (r=0.901 and P value <0.001). CONCLUSIONS: The rate of occurrence of NOD in COPD was 46.6%. Awake SPO2 is the only single predictor of nocturnal oxygen desaturation in these patients.

Kinetics of theophylline in apnea of prematurity in small for gestational age babies.

OBJECTIVES: To study the pharmacokinetics of theophylline and its correlations to pharmacodynamic effects in apnea of prematurity in small for gestational age babies. DESIGN: Prospective case control study. SETTING: Level III Neonatal Intensive Care Unit. SUBJECTS: Ten small for gestational age (SGA) babies and 10 gestation matched appropriate for gestational age (AGA) babies with recurrent apnea of prematurity. METHODS: All babies were investigated to exclude secondary causes of apnea. 5 mg/kg of aminophylline loading dose followed by 2 mg/kg as maintenance dose every 8 hourly intravenously was used. The trough and peak levels of theophylline were assessed on different days of therapy. Clinical monitoring was done for the efficacy and toxicity of the drug. Analysis was done using unpaired Student's 't' test and the correlation between plasma theophylline levels of different days was performed by using ANOVA. RESULTS: The therapeutic drug levels were achieved within 24 hours in all babies. The SGA babies showed 25% higher drug levels as compared to AGA babies. The mean trough plasma theophylline levels ranged from 8.15 +/- 1.59 to 12.37 +/- 1.54 micrograms/ml in SGA babies while in AGA babies they ranged from 6.26 +/- 1.93 to 9.96 +/- 1.96 micrograms/ml in first 8 days of therapy. The mean peak levels in SGA babies ranged from 11.91 +/- 1.84 to 17.13 +/- 1.63 micrograms/ml and in AGA babies ranged from 8.17 +/- 1.84 to 13.02 +/- 1.48 micrograms/ml. Twenty per cent SGA and AGA babies each developed clinical toxicity though toxic drug levels were found in 50% SGA and 30% AGA babies. CONCLUSION: There is a need to modify dosage schedule for these babies.

Sleep polygraphic parameters in neuromuscular diseases

Estudando 32 pacientes com doenças neuromusculares - 22 com forma de distrofia muscular, 3 com forma de miopatia congênita, 4 com forma de atrofia muscular espinal, 1 com forma recorrente de polimiosite e 1 com sídrome de osteogenesis imperfecta - dos quais 21 estavam impossibilitados de deambulaçäo, distúrbios respiratórios relacionados ao sono foram observados sob forma dessaturaçäo da oxi-hemoglobina, arritmia cardíaca, taquipnéia, taquicardia e roncos. Nove desses 32 pacientes apresentaram períodos de dessaturaçäo de oxi-hemoglobina maiores que 4 por cento em relaçäo aos níveis obtidos em vigília e repouso. Esse grupo de pacientes era caracterizado por apresentar síndrome respiratória associada a deformidade torácica (principalmente escoliose). Alguns apresentaram taquipnéia e/ou saturaçäo da oxi-hemoglobina abaixo de 90 por cento durante o repouso e em vigilia. Neste grupo, roncos foram observados principalmente nos pacientes com forma de distrofia muscular, enquanto a taquipnéia foi observada sobretudo nos pacientes com os maiores níveis de dessaturaçäo. A quantificaçäo do sono mostrou aumento na porcentagem do estado 1 do sono associada a diminuiçäo ou mesmo ausência do estado do sono paradoxal. Isso nos leva a crer em um provável mecanismo de proteçäo consequente à potencializaçäo da hipoventilaçäo observada durante o estado de sono paradoxal, em que os maiores níveis de dessaturaçäo säo observadas

Pierre Robin sequence and obstructive sleep apnea

É relatado o caso de paciente do sexo feminino de 12 anos de idade, com sequência de Pierre Robin, cuja reduçäo da luz faríngea leva a apnéia do sono tipo obstrutivo e consequente sonolência excessiva diurna. Estudo radiológico articular, tomografia computadorizada e ressonância nuclear magnética evidenciam anquilose bilateral da articulaçäo têmporo-mandibular. Cefalometria mostra reduçäo acentuada do espaço aéreo posterior. Polissonografia realizada durante três noites inteiras apresenta síndrome de apnéia do sono tipo obstrutivo, severa, acompanhada de reduçäo da saturaçäo de oxigenio. No Teste das Latências Múltiplas do Sono (TLMS) há objetivamente sonolência excessiva diurna, com descréscimo da latência do sono; näo ocorre estágio REM. Avaliaçäo polissonográfica, do TLMS e radiológica extensa permitem, neste caso, estagiar a severidade de acometimento e as malformaçöes concomitantes e detectar o sítio de obstruçäo

Arterial oxygen desaturation rate following obstructive apnea in parturients

This study was attempted to observe the rate of oxygen desaturation after full oxygenation in six parturients scheduled for Cesarean sections and six patients scheduled for transabdominal hysterectomies. We calculated the mean rate of fall of arterial saturation (slope of desaturation: less than SaO2 (t2)-SaO2(t1) greater than/t2-t1) and changes in arterial blood gases were observed. All subjects were denitrogenated then a single isolated apnea was carried out. The mean time to obtain 90% saturation was longer in the nonpregnant group (7.5 min vs 3.6 min in parturients). The mean slope of desaturation was steeper in the parturients (-3.34) than the nonpregnant group (-1.52). As far as the oxygen reserve is concerned, the parturients had a lesser margin of safety than the nonpregnant women. It was concluded that the lower the thoracic gas volume (parturients), the lower the alveolar O2 stores and, the more rapidly these stores are depleted.