Protriptyline in obstructive sleep apnea: a double-blind trial

We evaluated protriptyline, a nonsedating tricyclic antidepressant, as a treatment for obstructive sleep apnea in a double-blind crossover study of five men. After two weeks of treatment, with no change in body weight, daytime somnolence was markedly reduced and nocturnal oxygenation was improved, although apnea duration and frequency were not significantly decreased. Rapid-eye-movement (REM) stage time as a fraction of the total sleep time was reduced during treatment from 0.231 +/- 0.031 to 0.107 +/- 0.013 (mean +/- S.E.M.) (P less than 0.05). REM apnea time as a fraction of total sleep time was reduced from 0.145 +/- 0.022 to 0.054 +/- 0.006 (P less than 0.05). REM reduction during treatment with protriptyline can account for decreased REM apnea time. Similar decreases in REM stage time and REM apnea duration and similar improvement in oxygenation continued after six months of treatment. In addition, body weight, apnea, and arousal frequency were decreased at this time. Although the obstructive sleep apnea was not resolved, it was reduced. Protriptyline can be effective in patients with sleep apnea when the disorder is not life-threatening.     

Effect of hyperbaric oxygen on microvascular anastomosis healing and patency in the rat

Recent evidence has shown that changes in blood viscosity and marked increases in both platelet count and fibrinogen concentration occur after exposure to hyperbaric oxygen (HBO). The purpose of the present study was to address whether repeated HBO therapy would increase either hematocrit or platelet count, and to determine if these changes would influence the patency of the microvascular anastomosis, as well as anastomotic healing. Eighty femoral arteries from 40 rats were divided into four groups (n = 10), and arterial anastomoses were performed on normal arteries in the first two groups, and on crushed arteries in the second two groups. One of the normal artery groups and one of the crushed artery groups received repeated HBO treatments for 5 days. Anastomotic patency rates, platelet count, hematocrit, and breaking strength were recorded. Among the results of this study were that: (1) there was no difference in patency rate following HBO treatment in both the normal and crushed artery groups; (2) platelet count was significantly higher following HBO treatment in the groups with the undamaged arteries; (3) breaking strength was significantly increased following HBO treatment in the groups with the crushed arteries. The authors concluded that HBO therapy may be useful in improving the healing of microvascular anastomoses in vessels that have undergone crush injury. Although HBO treatment results in an increased platelet count, this does not influence anastomotic patency.     

Learning curve of microvascular venous anastomosis: a never ending struggle?

In this study, a simple protocol based on the rat femoral venous anastomosis was established to provide a quantitative representation of the progress. The learning curve is based on the patency rate in each consecutive group of five anastomoses. Two groups of surgeons were observed. The inexperienced group encountered a tough time in the first 25 anastomoses. However, the progress was fast and is represented by the steep slope of the curve. A plateau was reached whereby the avearge patency rate matches that of the experienced group. As expected, there was no learning curve for the experienced group. Despite every effort to attempt to maintain a perfect 100% patency on this model, the best achievable patency was only 88%. The results and its implication are discussed.     

Surgical management of urinary incontinence in children with neurogenic sphincteric incompetence

PURPOSE: There are many alternatives for the surgical treatment of children with neurogenic sphincteric incompetence. However, there is no consensus regarding appropriate evaluation and long-term management in these patients. We critically reviewed the literature and compare the outcomes of each technique. MATERIALS AND METHODS: A MEDLINE search was performed to select all relevant peer reviewed publications since 1966. In addition, the bibliography of each article was examined for additional published resources. The results of each technique were compared in 7 objective categories, including continence (defined as complete dryness for 4 hours between voidings or catheterizations), the need for intermittent catheterization, effects on bladder compliance, the need for bladder augmentation, upper tract changes, other complications and the revision rate. RESULTS: Long-term results of artificial urinary sphincter placement were superior and reproducible in terms of continence, preservation of volitional voiding and avoidance of bladder augmentation. Revision rates of various procedures were similar but the incidence of complications was highest with the Kropp procedure. Long-term published data were limited in regard to bladder neck sling, reconstruction, injection, suspension and urethral lengthening techniques. CONCLUSIONS: Long-term published data support artificial urinary sphincter creation as first line surgical management of neurogenic sphincteric incontinence. Girls who already depend on intermittent catheterization may benefit equally from a sling procedure if successful long-term continence is demonstrated in future studies.     

Identification and quantification of apneas by computer-based analysis of oxygen saturation

Manual detection and quantitation of apneas from an all-night polysomnogram is very time-consuming. Because SaO2 changes with virtually every apnea event, we reasoned that by identifying cyclical SaO2 changes, we could calculate (1) an apnea-hypopnea index that would correlate very well with the manually derived apnea-hypopnea index, and (2) the duration of apnea-hypopnea events. We developed a computer algorithm to scan and detect dips in SaO2 data digitally stored as a time series by computer throughout overnight studies. Desaturations detected by computer were compared with the events detected manually in 9 all-night polysomnograms from 6 patients with typical obstructive sleep apnea. Events detected by one method but not the other were subsequently verified to determine the overall number of apnea-hypopnea events present and to determine false positive and false negative rates for the 2 methods of detection. The total number of apneas was 4,008. Both methods agreed on 3,639 of them. Of 77 manually recorded apneas not detected by computer, 24 were subsequently discounted (manual false positives, 24 of 4,007 = 0.6%) and 53 confirmed (computer false negatives, 1.32%). Of 358 events not detected manually, 316 were confirmed (manual false negatives, 7.9%) and 42 discounted (computer false positives, 1.1%). Using the final manual scoring as the reference, the computer program detected apneas with a sensitivity of 97.9%, and the predictive value of a computer-detected event was 90.8%. For event duration, a regression was performed on 3,623 matched apneas-hypopnea events, giving a coefficient of r = 0.9431, p less than 10(-6).(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of oxygen on respiration and sleep in patients with congestive heart failure

STUDY OBJECTIVE: To determine the effect of supplemental oxygen on Cheyne-Stokes respiration, nocturnal oxygen saturation (SaO2), and sleep in male patients with severe, stable congestive heart failure. DESIGN: Randomized, single-blind, placebo-controlled crossover study. SETTING: Patients referred from outpatient cardiology clinics of two teaching hospitals. PATIENTS: Sequential sample of nine outpatients with severe, stable congestive heart failure. INTERVENTIONS: For each patient, sleep studies (after an adaptation night) from two consecutive randomized nights were compared; one study was done while the patient breathed compressed air and the other while the patient breathed oxygen (O2). Compressed air and oxygen were both administered through nasal cannulae at 2 to 3 L/min. MEASUREMENTS AND MAIN RESULTS: Cheyne-Stokes respiration, defined as periodic breathing with apnea or hypopnea, was found in all patients. Low-flow oxygen significantly reduced the duration of Cheyne-Stokes respiration (50.7% +/- 12.0% to 24.2% +/- 5.4% total sleep time), mainly during stage 1 NREM (non-rapid eye movement) sleep (21.3% +/- 7.1% to 6.7% +/- 2.3% total sleep time) with no significant change during stage 2 sleep, slow-wave sleep, or REM (rapid eye movement) sleep. Although patients had normal SaO2 (96.0% +/- 1.7%) while awake, severe sleep hypoxemia was common; breathing oxygen reduced the amount of time that SaO2 was less than 90% from 22.3% +/- 8.0% to 2.41% +/- 1.93% of total sleep time. Sleep, disrupted to a variable extent in all patients, improved with oxygen therapy: There was an increase in total sleep time from 275.3 min +/- 36.6 to 324.6 min +/- 23.3; a reduction in the proportion of stage 1 sleep (27.6% +/- 5.8% total sleep time to 15.2% +/- 2.6% total sleep time); and a reduction in the number of arousals (30.4/h +/- 8.0 to 13.8/h +/- 1.9). The apnea-hypopnea index was reduced from 30.0 +/- 4.7 to 18.9 +/- 2.4 with oxygen breathing. CONCLUSION: In severe, stable congestive heart failure, nocturnal oxygen therapy reduces Cheyne-Stokes respiration, corrects hypoxemia, and consolidates sleep by reducing arousals caused by the hyperpneic phase of Cheyne-Stokes respiration. Correction of nocturnal hypoxemia and sleep disruption may improve the clinical status of these patients.     

乐胃煎逆转胃癌前病变AgNOR及细胞图像分析

目的研究乐胃煎逆转胃癌前病变不完全结肠型肠化和／或中度异型增生的疗效．方法胃镜病理证实为不完全结肠型肠化和／或中度异型增生４６例．治疗组３０例用乐胃煎，对照组１６例用德诺（Ｄｅ＿Ｎｏｌ）．治疗前后胃镜活检胃窦固定部位粘膜标本作ＡｇＮＯＲ染色及细胞图像分析．结果乐胃煎对不完全结肠型肠化及中度异型增生总有效率均高于Ｄｅ＿Ｎｏｌ，分别为７２％比２５％（Ｐ＜００５）和８９５％比４４４％（Ｐ＜００５）．乐胃煎治疗前后，ＡｇＮＯＲ计数分别为７３０±１１６和４８１±１５０（Ｐ＜００１），Ｄｅ＿Ｎｏｌ组为７７３±０９２和７０５±１０２（Ｐ＜００１）．两组治疗前后ＡｇＮＯＲ计数差值均数相比，统计学上也有显著性差异，分别为２５２±１５４和０６９±０４８（Ｐ＜００１）．乐胃煎组中２０例作细胞图像分析，治疗后各参数（长轴、短轴、核浆比、结构异型指数等）均有不同程度的降低，有显著性差异．结论乐胃煎确有较好地逆转胃癌前病变的功效．     

Nasal CPAP reduces gastroesophageal reflux in obstructive sleep apnea syndrome.

Anecdotal reports suggest that obstructive sleep apnea syndrome (OSAS) patients may suffer from frequent nocturnal gastroesophageal reflux (GER) and that nasal continuous positive airway pressure may be an effective form of antireflux therapy in this population. To confirm these clinical impressions, we performed two consecutive days of 24-h esophageal pH monitoring, nocturnal esophageal pressure recording, and polysomnography on six OSAS patients complaining of regular nocturnal GER. On night one, the patients were untreated. Five of six subjects had abnormal amounts of nocturnal GER. Arousal, movement and swallowing were more frequent (p less than 0.043) and nadir intrathoracic pressure lower (p less than 0.005) in the 30 s prior to precipitous drops in esophageal pH (greater than or equal to 2 pH units) than during random control periods. A direct association between obstructive apneas and GER was not identified. On night two, nasal CPAP was administered and successfully treated apnea in five of six subjects. In these patients, there was also dramatic reduction in GER frequency and duration on CPAP. The mean percentage of time pH less than 4 dropped from 6.3 +/- 2.1 to 0.1 +/- 0.1 percent (p less than 0.025). We believe that OSAS may predispose to nocturnal GER by lowering intrathoracic pressure and increasing arousal and movement frequency. Nasal CPAP can correct these predisposing factors and reduce GER.