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Fang Han

Publications and source records attributed to Fang Han.

At least 37 records · Page 2Linked to original sources
PubMed2005

Preconcentration and determination of trace metals in seawater using a thiol cotton fiber minicolumn coupled with inductively coupled plasma mass spectrometry.

A rapid separation and preconcentration method was developed for the determination of trace metals Cu, Zn, Cd, and Pb in seawater using a minicolumn packed with thiol cotton fiber (TCF) coupled with inductively coupled plasma mass spectrometry (ICP-MS). Preconcentration parameters, such as seawater sample volume and flow rate and eluent hydrochloric acid concentration, volume and flow rate, were optimized. Under the optimized conditions, trace metals Cu, Zn, Cd, and Pb in seawater can be determined with no interference from saline matrices. When a sample volume of 1500 ml and a sample flow rate of 15 ml min(-1) were used, the preconcentration factor of 1500 and RSD value of <7% at ng ml(-1) were achieved. The accuracy of the recommended method was verified by the analysis of certified reference materials.

Journal Article↗
PubMed2005

[Gastrointestinal stromal tumor: a clinicopathological study of 74 cases].

OBJECTIVE: To explore a simplified and reproducible approach for the diagnosis and morphologic prognostication of gastrointestinal stromal tumor (GIST). METHODS: Eighty-five cases of gastrointestinal mesenchymal tumors including 74 cases of GIST, 8 esophageal smooth muscle tumor, 1 rectal leiomyosarcoma, 1 Schwannoma, and 1 malignant fibrous histiocytoma were studied by histological evaluation along with an immunohistochemistry panel including vimentin, CD117 (c-kit), CD34, SMA, desmin and S-100. Clinicopathological correlation was performed in 31 cases of GIST that had accompanied with the available follow-up data. RESULTS: Among 74 GISTs, 34 arose principally from the stomach, 30 from the small intestine, and 10 other cases found in the esophagus, retroperitoneum, mesenterium and omentum. The patients' age ranged from 23 to 80 years (mean 52.5 years), with 45 males and 29 females. Histologically, the tumors composed of either spindle or oval to round cells arranged in interlacing fascicles forming whorls or cellular clusters, cytoplasm generally abundant and eosinophilic. There were 48 cases of spindle cell type, 10 cases of epithelioid cell type and 16 cases of mixed cell type. All 74 cases of GIST were positive for CD117 in a cell membranous pattern, however, some variable staining patterns of CD117 had been noticed in a few cases. In addition, 54 GISTs were also positive for CD34 (72.9%), 25 cases positive for SMA, 5 cases positive for S-100 and 5 cases positive for desmin. According to the Fletcher's scheme, GISTs in this study were divided into 4 subcategories including groups of very low risk of aggressive behavior (3 cases), of low risk (15 cases), of intermediate risk (36 cases) and of high risk (20 cases) respectively. Kaplan-Meier survival analysis of 31 GIST cases whom had been followed up for 16 to 72 months showed a statistically significant difference present among the subcategories (P < 0.01). CONCLUSIONS: GISTs predominantly occur in the middle and old age patients, more common in male, and positive CD117 staining is considered to be the defining marker to differentiate GIST from other mesenchymal tumors of the GI tract. Positive CD34 immun-staining, plus a CD117 positivity, strengthens further a diagnosis of GIST. Subclassification of GISTs using Fletcher's scheme appears to be simple, reproducible, and correlates well with the clinical behavior of the tumor.

Actins↗
PubMed2005

[Effects of uvulopalatopharyngoplasty surgery on subsequent continuous positive airway pressure in patients with obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To determine the effect of uvulopalatopharyngoplasty (UPPP) therapy on post-surgery continuous positive airway pressure (CPAP) treatment during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), and to evaluate the use of Bi-level positive airway pressure (BiPAP) in whom CPAP therapy failed. METHODS: Thirty-four OSAHS patients after UPPP surgery were tested more than 3 months after the procedure. Among them 25 patients were treated with classical UPPP (cUPPP), in which all of the uvula and part of the soft palate were removed. Nine underwent modified UPPP (mUPPP), keeping part of the uvula. The control group consisted of 34 age, body mass index (BMI) and apnea hypopnea index (AHI) matched, newly diagnosed OSAHS patients without prior treatment. Four patients receiving both pre- and post-surgery tests were included in both groups. A manual titration of CPAP to determine the optimal CPAP pressure (oCPAP) and the highest CPAP pressure (hCPAP) the patient can tolerate was performed during both NREM and REM sleep in all 68 patients. RESULTS: 72% of the UPPP patients had less than 50% decrease in AHI, and 82% of the 34 patients still had AHI > 15 during post-operation PSG test. Hence, most of them needed further therapy. All of the untreated OSAHS patients could tolerate 17-20 cm H2O of CPAP during NREM and REM sleep. None had severe mouth air leak before an oCPAP was reached. In contrast, five in the surgery group failed to respond to CPAP treatment during both NREM and REM sleep, and one more during REM sleep. All of the nine patients who had a mUPPP could tolerate CPAP. One of the four tested both before and after surgery failed to respond to CPAP treatment after surgery during REM sleep and one during both NREM and REM sleep. However, the six patients failed to respond to CPAP treatment tolerated BiPAP therapy well. CONCLUSIONS: In a considerable number of patients with OSAHS, UPPP may compromise the applicability of nasal CPAP as a subsequent therapy, and BiPAP might be a treatment option for patients who could not tolerate CPAP treatment.

Adult↗
PubMed2004

Noninvasive positive pressure ventilation treatment for acute respiratory failure in SARS.

This study describes the blood gases features and short-term outcomes with noninvasive positive pressure ventilation (NPPV) treatment in the management of acute respiratory failure (ARF) during a severe acute respiratory syndrome (SARS) epidemic. Between April 22 and May 1, 2003, 120 patients meeting clinical criteria for SARS were admitted to a hospital for infectious diseases in Beijing, China. At 6 weeks after onset, 25% of patients (30/120) had experienced ARF. Of interest, 16 of these patients (53%) exhibited hypercapnia (PaCO (2) > 45 mm Hg), and 10 hypercapnic events occurred within 1 week of admission. The occurence of hypencapnia or CO (2) retention and was accompanied by myalgias. NPPV was instituted in 28 patients; one was intolerant of NPPV. In the remaining 27 patients, NPPV was initiated 1.2 +/- 1.6 days after ARF onset. An hour of NPPV therapy led to significant increases in PaO (2) and PaO (2)/FiO (2) and a decrease in respiratory rate ( p < 0.01). Endotracheal intubation was required in one third of the patients (9 of 27) who initially had a favorable response to NPPV. Remarkable pulmonary barotrauma was noticed in 7 of all 120 patients (5.8%) and in 6 of those (22%) on NPPV. The overall fatality rate at 13 weeks was 6.7% (8/120); it was higher (26.7%) in those needing NPPV. No caregiver contracted SARS. We conclude that NPPV is a feasible and appropriate treatment for ARF occurring as a result of a SARS infection.

Acute Disease↗
PubMed2004

Strain differences in murine ventilatory behavior persist after urethane anesthesia.

Differences in breathing pattern between awake C57BL/6J (B6) and A/J mice are such that A/J mice breathe slower, deeper, and with greater variability than B6. We theorized that urethane anesthesia, by affecting cortical and subcortical function, would test the hypothesis that strain differences require a fully functional neuroaxis. We anesthetized B6 and A/J mice with urethane, placed them in a whole-body plethysmograph, and measured the durations of inspiration and expiration, respiratory frequency (Fr), and peak amplitude during exposure to room air (21% O2), hyperoxia (5 min, 100% O2), hypoxia (5 min, 8% O2), and posthypoxic reoxygenation (5 min, 100% O2). Breathing variability was assessed by calculating the coefficient of variation (CV) and by applying spatial statistics to Poincaré plots constructed from the timing and amplitude data. Even though Fr in anesthetized B6 and A/J mice was greater than that for unanesthetized animals, anesthetized A/J mice still breathed slower, deeper, and with greater variability than B6 mice at rest and during hyperoxia. During the fourth minute of hypoxia, Fr and its CV were not significantly different between strains. Even though Fr was similar between strains immediately after hypoxia, its CV was significantly greater for B6 than A/J mice. Posthypoxic Fr was significantly less than baseline Fr in B6 but not A/J mice, and the CV for posthypoxic Fr was greater for B6 but less for AJ mice compared with baseline CV. This difference in patterning was confirmed by spatial statistical analysis. We conclude that strain-specific differences in respiratory pattern and its variability are robust genetic traits. The neural substrate for these differences, at least partially, exists within subcortical structures generating the breathing pattern.

Anesthetics, Intravenous↗
PubMed2004

Ventilatory behavior during sleep among A/J and C57BL/6J mouse strains.

The pattern of breathing during sleep could be a heritable trait. Our intent was to test this genetic hypothesis in inbred mouse strains known to vary in breathing patterns during wakefulness (Han F, Subramanian S, Dick TE, Dreshaj IA, and Strohl KP. J Appl Physiol 91: 1962-1970, 2001; Han F, Subramanian S, Price ER, Nadeau J, and Strohl KP, J Appl Physiol 92: 1133-1140, 2002) to determine whether such differences persisted into non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Measures assessed in C57BL/6J (B6; Jackson Laboratory) and two A/J strains (A/J Jackson and A/J Harlan) included ventilatory behavior [respiratory frequency, tidal volume, minute ventilation, mean inspiratory flow, and duty cycle (inspiratory time/total breath time)], and metabolism, as performed by the plethsmography method with animals instrumented to record EEG, electromyogram, and heart rate. In all strains, there were reductions in minute ventilation and CO2 production in NREM compared with wakefulness (P < 0.001) and a further reduction in REM compared with NREM (P < 0.001), but no state-by-stain interactions. Frequency showed strain (P < 0.0001) and state-by-strain interactions (P < 0.0001). The A/J Jackson did not change frequency in REM vs. NREM [141 +/- 15 (SD) vs. 139 +/- 14 breaths/min; P = 0.92], whereas, in the A/J Harlan, it was lower in REM vs. NREM (168 +/- 14 vs. 179 +/- 12 breaths/min; P = 0.0005), and, in the B6, it was higher in REM vs. NREM (209 +/- 12 vs. 188 +/- 13 breaths/min; P < 0.0001). Heart rate exhibited strain (P = 0.003), state (P < 0.0001), and state-by-strain interaction (P = 0.017) and was lower in NREM sleep in the A/J Harlan (P = 0.035) and B6 (P < 0.0001). We conclude that genetic background affects features of breathing during NREM and REM sleep, despite broad changes in state, metabolism, and heart rate.

Animals↗
PubMed2004

Exocytosis sensitivity to growth hormone-releasing hormone in subsets of GH cells in rats under different corticosterone conditions. Ultrastructural study using microwave irradiation for fixation and immunocytochemistry.

Growth hormone (GH) cells in the rat anterior pituitary have been morphologically classified into three subtypes: type I (mature) containing large secretory granules about 350 nm in diameter, type II (intermediate) containing a mixture of large and small granules, and type III (immature) containing small granules about 150 nm in diameter. However, the functional implications of morphological heterogeneity, especially the different sensitivities to growth hormone-releasing hormone (GRH) under different corticosteroid conditions have not been elucidated to date. In the present study, by application of microwave irradiation (MWI) for fixation and immunocytochemistry, new findings of the exocytotic response have been revealed among the subsets of GH cells following adrenalectomy (ADX), corticosterone treatment and/or GRH treatment. The MWI gave effective results for fixation, especially for the permeability of the fixative, and showed good results for immunoelectron microscopy using the protein-A gold method. Moreover, the use of MWI greatly shortened the fixation, processing and immunolabeling times without compromising the quality of ultrastructural preservation and the specificity of labeling. The number of exocytotic figures was low in all subtypes of GH cells in the sham-operated control rats. GRH treatment induced a significant increase in exocytosis in each subtype of GH cells, particularly in type I (mature) and type II (intermediate) GH cells in the control rats. GRH injection to rats for 4 days after ADX also showed an increase in exocytosis, but the degree was significantly less in comparison with the GRH injection in the control group. Corticosterone replacement given to ADX rats induced a clear recovery of the exocytotic response to GRH to the control level. Serum GH content measured by radioimmunoassay correlated with these morphological results. These results suggest that the secretion of GH stimulated by GRH is closely related to corticosteroids, and that the sensitivity to GRH differs among the three subtypes of GH cells.

Animals↗
PubMed2004

[Diagnosis of childhood narcolepsy and significance of HLA in its diagnosis].

OBJECTIVE: Narcolepsy is a lifelong sleep disorder characterized by excessive daytime sleepiness, and features of rapid eye movement (REM) sleep, such as cataplexy, sleep paralysis and hypnagogic hallucinations. The present study aimed to investigate the diagnostic basis of childhood narcolepsy and possible role of HLA Class II alleles in the onset of this disease. METHODS: The clinical data of 40 narcoleptic children were analyzed. All patients received Multiple Sleep Latency Test (MSLT) and they were analyzed in combination with clinical features. Polymerase chain reaction/sequence specific primers (PCR/SSP) methods were used to detect the HLA-DRB1 and DQB1 alleles. RESULTS: Narcolepsy was diagnosed in 40 children. The age range was 3 to 14 years (mean 8.5 +/- 2.5 years), 29 were male and 11 female. Their mean course of disease was 6.5 months, 14 patients (30%) were less than 3 months old, 21 patients (52%) were less than 6 months old. All the patients had excessive daytime sleepiness, cataplexy appeared in 37 cases, hypnagogic hallucination in 22 and sleep paralysis in 6. Mean sleep latency on MSLT was less than 5 min, the average number of sleep-onset rapid eye movement (SOREM) was 4.33 +/- 0.26 episodes (2-5 episodes), the latency of SOREM episodes were 4.0 +/- 1.8 min (0.25-4.9 min). Thirty-five patients were DRB1 1501 and DQB1 0602 positive (Pc < 0.01), 2 were DRB1 1502 and DQB1 0601 positive, while 3 were DRB1 15 and DQB1 6 negative. CONCLUSIONS: Some pediatric patients with narcolepsy were different from adult patients in that the pediatric cases had a sudden onset and shorter disease course. Diagnosis of this disease was based on the clinical manifestations, MSLT and absence of any medical or psychiatric disorder that could account for the symptoms. The authors demonstrated that DRB1 1501 and DQB1 0602 were susceptibility genes for narcolepsy and those who were DRB1 15 negative could not be excluded.

Adolescent↗
PubMed2004

[Influence of different sleep stages on respiratory regulation in normal humans].

OBJECTIVE: To understand the influence of different sleep stages on respiratory regulation in normal people. METHODS: We measured ventilation (VE) and occlusion pressure (P0.1) responses to hyperoxia hypercapnia (deltaVE/deltaPaCO2, deltaP0.1/deltaPaCO2) and isocapnic hypoxia (deltaVE/deltaSaO2 and deltaP0.1/deltaSaO2) in eleven non-snoring healthy people during wakefulness and during non-rapid eye movement (NREM) I + II, NREM III+IV, and rapid eye movement (REM) sleep stages. RESULTS: During NREM I + II and NREM III+IV, the normal subjects showed no significant decrease in P0.1, deltaP0.1/deltaSaO2 and deltaP0.1/deltaPaCO2 (P > 0.05), but deltaVE/ deltaSaO2 and deltaVE/ deltaPaCO2 decreased significantly (P < 0.05). During REM sleep, P0.1 maintained the level during wakefulness, but both hypoxic and hypercapnic responses decreased significantly (P < 0.05). CONCLUSIONS: Sleep has significant influence on respiratory regulation in normal people. The respiratory drive (P0.1) in both NREM and REM sleep stages could maintain the awake level due to an effective compensation to the increase of upper airway resistance. The P0.1 responses to both hypoxia and hypercapnia decrease only in REM sleep stage, which is in consistent with the clinical phenomenon that sleep disordered breathing occurs in REM in normal people.

Adult↗
PubMed2004

[Acute respiratory failure and noninvasive positive pressure ventilation treatment in patients with severe acute respiratory syndrome].

OBJECTIVE: To describe the blood gas features and short-term outcomes of noninvasive positive pressure ventilation (NPPV) treatment for acute respiratory failure (ARF) in patients with severe acute respiratory syndrome (SARS) in this retrospective case series study sought. METHODS: Between April 22 and May 1, 2003, 120 clinically compatible SARS patients were admitted to a special hospital for infectious diseases in Beijing. All patients' records were reviewed. The outcome variables of NPPV therapy were analyzed. RESULTS: At 6 weeks of SARS onset, 25% (30/120) patients had respiratory failure with ALI/ARDS. 16 (53%) had hypercapnia (PaCO(2) > 45 mm Hg) during the course of SARS. 28 of them received NPPV therapy. One was intolerable to NPPV treatment. In the remaining 27 patients, NPPV was initiated 1.2 +/- 1.6 (0 - 10) days after onset of respiratory failure. One hour of NPPV therapy led to significant increases in PaO(2), SpO(2) and PaO(2)/FiO(2), and decrease in respiratory rate (all P < 0.01). 18 of the 27 patients were weaned successfully from NPPV. The mean duration of NPPV use was 10 +/- 6 (5 - 30) days. In addition to one patient who was intolerable to NPPV treatment, intubation was required in other 9 patients who initially had a favorable response to NPPV. Remarkable pulmonary barotrauma was noted in 7 of the 120 (5.8%) patients with SARS, among which 1 developed 2 days after intubation, and 6 occurred while the patients were on NPPV, the incidence being 22% (6/27) in patients using NPPV. The fatality rate at 13 weeks of SARS onset was 6.7% (8/120) in the patient cohort, and 26.7% (8/30) in the ALI/ARDS patients. No SARS occurred in medical staff taking care of NPPV patients. CONCLUSIONS: Some of the SARS patients with ALI/ARDS could experience CO(2) retention, which might be related to the impairment of respiratory muscles. It is proved to be feasible and appropriate for NPPV treatment of respiratory failure in SARS patients who were at high risk of intubation related complications. As there was a high incidence of remarkable barotrauma, a careful lung protective strategy is necessary during the administration of NPPV as well as invasive mechanical ventilation.

Adult↗
PubMed2003

[HLA-DRB and -DQB allele contribution to narcolepsy susceptibility in Chinese patients with narcolepsy].

OBJECTIVES: To study the association of narcolepsy with HLA class II alleles in Chinese narcoleptic patients. METHODS: 31 patients with narcolepsy underwent brain computed tomography (CT) scan and magnetic resonance imaging (MRI) testing. All patients received a MSLT test following a routine night's sleep, and serological HLA typing for HLA DR(2). 21 patients received PCR-SSP HLA DR and DQ typing. RESULTS: All patients had sleepiness and cataplexy. There was no evidence for other functional or structural diseases. Sleep paralysis was elicited in 45%; hypnagogic hallucinations, in 61%. Mean sleep latency on MSLT was 2.1 min +/- 1.3 min; sleep-onset rapid eye movement (SOREM) occurred during 2/5 naps in 30 of 31 patients. The average number and latency of SOREM episodes were 4.2 +/- 1.0 episodes and 4.0 min +/- 1.8 min, respectively. All patients but one were HLA DR(2) positive and 86% were HLADRB(1) * 1501-HLADQB(1)*0602 positive. CONCLUSIONS: HLA DR(2) and HLADQw6 are markers for narcolepsy-cataplexy in Chinese.

Adolescent↗
PubMed2003

7-nitroindazole and posthypoxic ventilatory behavior in the A/J and C57BL/6J mouse strains.

Periodic breathing (PB) is a fundamental breathing pattern in many common cardiopulmonary illnesses. The finding of PB in C57BL/6J (B6) mice was previously ascribed to strain differences in posthypoxic ventilatory and frequency decline in the B6 mice (Han F, Subramanian S, Price ER, Nadeau J, and Strohl KP. J Appl Physiol 92: 1133-1140, 2002). We tested whether the induction of posthypoxic frequency decline in A/J mice, through administration of a neuronal nitric oxide synthase blocker [7-nitroindazole (7-NI); 60 mg/kg], would cause A/J mice to exhibit PB and/or alter PB expression in the B6 strain. Recordings of ventilatory behavior by the plethysmography method were made when unanesthetized B6 (n = 10) or A/J (n = 6) animals were reoxygenated with 100% O2 or room air after exposure to 8% O2. Before undergoing gas challenges, mice were given an intraperitoneal injection of either peanut oil alone (vehicle) or 7-NI suspended in peanut oil. Compared with vehicle, both strains of mice exhibited posthypoxic frequency decline and the absence of short-term potentiation with 7-NI administration. B6 mice continued to exhibit posthypoxic PB; however, the PB was characterized by longer cycle and apnea length. In contrast, A/J mice did not show increased tendency toward posthypoxic PB with 7-NI. We conclude that 7-NI further differentiates the A/J and B6 strains in terms of PB and that strain-related differences in posthypoxic frequency decline are not primary determinants of this strain difference in the occurrence of PB. Metabolism was not associated with either the expression of posthypoxic ventilatory decline or PB. Furthermore, neuronal nitric oxide may be an organizing feature in the presence, length, and/or cycle length of apnea in the susceptible strain.

Animals↗
PubMed2003

[Overexpression of c-erbB-2 and hypoexpression of nm23 relating to poor prognosis of colorectal carcinoma].

OBJECTIVE: To investigate the relationship between expression of c-erbB-2, CD44v6 and nm23 gene proteins and the clinicopathological features of colorectal carcinomas. METHODS: Immunohistochemical technique was adopted to detect the protein expression of c-erbB-2, CD44v6 and nm23 genes in 92 cases of colorectal carcinomas. Of the 92 cases, 28 cases were followed up for more than 10 years, in which the prognosis was analyzed. RESULTS: Expression of c-erbB-2 and CD44v6 was correlating with UICC staging (P < 0.05), and c-erbB-2 was associated with prominent peritumoral lymphocytic infiltration (P < 0.05). In the 28 cases with followed-up data, univariant analysis revealed that the survival rate was correlated with histological grading, UICC staging, tumor growth pattern, peritumoral lymphocytic infiltration, and expression of c-erbB-2, CD44v6 and nm23. However, Cox stepwise proportional hazards analysis showed that only UICC staging, c-erbB-2 and nm23 status retained significant independently in prospecting prognosis. CONCLUSIONS: Besides UICC III and IV stage, overexpression of c-erbB-2 and decreased expression of nm23 are considered acceptable as the parameters in predicting of poor prognosis in colorectal carcinoma.

Adenocarcinoma↗
PubMed2003

[Epidemiologic study on sleep apnea-hypopnea syndrome by home investigation in Chengde city].

OBJECTIVE: To investigate the prevalence of sleep apnea-hypopnea syndrome (SAHS) among adults aged over 30 yr in Chengde city of Hebei province. METHODS: 1 168 subjects (over 30 yr) were derived from a random sample of the population among the Shuangqiao district in Chengde city. All subjects were asked at home to answer questions about their snoring, daytime sleepiness, and habits of smoking and drinking. According to the degree of snoring, 127 moderate and severe snorers were measured by portable PSG for a whole night and the prevalence of SAHS was estimated according to AHI and ESS scores. RESULTS: 1 168 subjects (95.42%) answered the questions. The prevalence of snoring was 53.76%. The prevalence of moderate and severe snoring (>or= second degree) was 28.25%. The prevalence of snoring increased with age before the age of 70. The prevalence of snoring in males was significantly higher than that in females. Smoking and drinking groups were associated with a higher prevalence of snoring. The prevalence of snoring was higher in drivers (42.00%) than that in other populations. The estimated prevalence of SAHS according to both the AHI > 5 and the ESS >or= 9 was 4.63%. CONCLUSIONS: The estimated prevalence of SAHS among adults aged over 30 yr in Chengde city was 4.63%. It means that SAHS needs better understanding and more study.

Adult↗
PubMed2003

[Retrospective analysis of the studies on sleep apnea-hypopnea syndrome in the past twenty years in our country].

OBJECTIVE: To summarize and evaluate the studies on sleep apnea-hypopnea syndrome (SAHA) in our country. METHOD: Articles on the study of SAHS published in major journals of our country from January, 1982 to June, 2002 were evaluated retrospectively. RESULTS: 262 articles were recruited. More papers covering more aspects of this disorder were getting published in the past 20 years. However, basic studies, multidisciplinary studies, more effective therapies and large size, multicenter, and prospective trials were lacking. The study of SAHS in different provinces did not reach the same level. CONCLUSION: Large sampled, multicenter and multidisciplinary prospective trials are needed to study more effective and acceptable therapies as well as the basic mechanism of SAHS.

Biomedical Research↗
PubMed2003

[Comparison of tolerance to sequential continuous positive airway pressure therapy between patients after classical and after modified uvulopalatopharyngoplasty].

OBJECTIVE: To investigate the effect of uvulopalatopharyngoplasty (UPPP) on postoperation continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: 66 OSAHS patients underwent UPPP were recruited and all were followed up for more than 12 months. Among them 24 patients were treated with classical UPPP, 42 had modified UPPP treatment. The efficacy of surgery was compared between the two groups. The post-operation tolerance to CPAP pressure was tested during sleep CPAP titration in 24 classical UPPP patients and in 15 modified UPPP patients. RESULTS: The validity ratio is 58.3% and 61.9% 12 months after operation. There was no significant difference between classical UPPP and modified UPPP in regard to surgery efficacy, and most of them need further CPAP therapy. During CPAP treatment, compared with untreated OSAHS patients, the highest CPAP pressure classical UPPP group could tolerant decreased significantly, however, classical UPPP group did not. 16.7% of classical UPPP patients had severe mouth air leak before optimal CPAP pressure was titrated, but none of the 15 post modified UPPP failed to sequential CPAP therapy. CONCLUSION: The efficacy was similar between modified UPPP and classical UPPP treatment, post modified UPPP patients had better tolerance to sequential CPAP treatment. It may be better to treat OSAHS patients with modified UPPP instead of classical UPPP.

Adult↗
PubMed2003

[Respiratory control during sleep and the development of nocturnal hypoxia in patients with obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: It is assumed that the reduced ventilatory control during sleep may be related to the nocturnal hypoxia in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and daytime CO(2) retention. METHODS: Oxygen desaturation index (ODI(4)), sleep time spent when SaO(2) was below 90% (SIT(90)), the lowest SaO(2) (LSaO(2)) and the mean SaO(2) (MSaO(2)) during sleep were measured in 24 OSAHS patients with daytime PaCO(2) > or = 45 mm Hg and 39 with PaCO(2) < 45 mm Hg. Hypoxic (DeltaP(0.1)/DeltaSaO(2)) and hypercapnic (DeltaP(0.1)/DeltaPaCO(2)) responsiveness were measured in 11 eucapnic and 4 hypercapnic patients during wakefulness, NREM and REM sleep stages. RESULTS: Compared with the eucapnic patients, all the hypercapnic patients had more severe hypoxia during sleep (P < 0.05). Although both groups had similar chemical responsiveness during wakefulness, the hypercapnic patients had lower DeltaP(0.1)/DeltaSaO(2) and DeltaP(0.1)/DeltaPaCO(2) during both REM and NREM sleep (P < 0.05). CONCLUSION: The depressed chemical responsiveness during sleep plays an important role in the development of nocturnal hypoxia in OSAHS patients with daytime CO(2) retention.

Carbon Dioxide↗