Biomedical subjects

M Wenzel

Publications and source records attributed to M Wenzel.

At least 37 records · Page 2Linked to original sources

PubMed1998

Red cell membrane skeletal changes in marathon runners.

Hemolysis in endurance exercise may be related to structural changes in red blood cell (RBC) membrane skeletal proteins. To test this hypothesis, we studied 13 male subjects before and after a marathon race. RBC membrane skeletons were observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Plasma haptoglobin was measured. RBCs were affixed on poly-l-lysine coated glass supports for SEM and copper grids with formvar were prepared for TEM. Cytoplasmatic materials and lipid membranes were extracted with Triton-X-100 solution. TEM specimens were negatively stained and air dried. For SEM, the remaining RBC membrane skeletons were fixed, postfixed and sputtered with platinum. RBC membrane skeletal areas on SEM micrographs were measured by digitizer table planimetry. No RBC changes were observed with TEM. On the other hand, SEM showed disrupted RBC membrane skeletons. Furthermore, there appeared to be a loss of membrane material in RBC after the race, compared to RBC before the race. RBC membrane skeletal areas were increased by 30% (p<0.01). Hemolysis was indicated by a 57% decrease in plasma haptoglobin values (p<0.001). Thus, structural changes in RBC membrane skeletons occur after a marathon race. These changes can be identified with SEM but not with TEM. They may be related to increased susceptibility to chemical and physical stress and may contribute to hemolysis in endurance exercise.

Adult↗

PubMed1998

Blood transfusion and lung function in chronically anemic patients with severe chronic obstructive pulmonary disease.

OBJECTIVE: To study in anemic patients with chronic obstructive pulmonary disease (COPD) whether blood transfusion reduces minute ventilation and work of breathing (WOB). DESIGN: We prospectively evaluated the minute ventilation and WOB in 20 anemic adults (hemoglobin of <11 g/dL). Ten patients had severe COPD and ten patients were without lung disease. Measurements were made before and after receiving red blood cell transfusion; post-transfusion measurements were made 24 to 36 hrs after the last transfusion. SETTING: The study was performed in the intensive care unit of a tertiary referral center for home mechanical ventilation and for patients considered difficult to wean from mechanical ventilation. PATIENTS: Twenty clinically stable patients (12 female, eight male) with chronic anemia were studied. Ten patients with COPD (mean forced expiratory volume in 1 sec: 0.55+/-0.1 [SD] L) were compared with ten patients without lung disease. All participants had adequate renal and left ventricular function. INTERVENTIONS: Patients received 1 unit of packed red blood cells for each g/dL that their hemoglobin value was less than an arbitrarily defined target value of 11.0 to 12.0 g/dL. Each unit was transfused over 2 hrs and < or =3 units in total was given. MEASUREMENTS AND MAIN RESULTS: Esophageal pressure was measured from a catheter which was positioned in the middle of the esophagus. Flow was measured using a pneumotachygraph connected to a mouthpiece while a nose clip closed the nostrils during the measurements. From these data, respiratory rate, minute ventilation, and inspiratory resistive WOB were computed. Arterial blood gas values, oxygen saturation, hemoglobin, and hematocrit were also measured, and oxygen content was calculated before and 24 to 36 hrs after transfusion. In patients with COPD, hemoglobin increased from 9.8+/-0.8 to 12.3+/-1.1 g/dL due to a mean transfusion of 2.2+/-0.4 (SD) units of red blood cells. There was a reduction in the mean minute ventilation from 9.9+/-1.0 to 8.2+/-1.2 L/min (p < .0001); correspondingly, WOB decreased from 1.03+/-0.24 to 0.85+/-0.21 WOB/L (p< .0001). The capillary P(CO2) increased from 38.1+/-6.0 to 40.7+/-6.8 torr (5.1+/-0.8 to 5.8+/-0.9 kPa) (p < .05). Similarly, capillary P(O2) changed from 56.9+/-8.9 to 52.8+/-7.0 torr (7.6+/-1.2 to 7.0+/-0.9 kPa) (p < .05). In anemic patients without lung disease, minute ventilation, WOB, and the capillary blood gas values did not change after increase of the hemoglobin by a similar degree. CONCLUSIONS: We conclude that red blood cell transfusion in anemic patients with COPD leads to a significant reduction of both the minute ventilation and the WOB. In these patients, transfusion may be associated with unloading of the respiratory muscles, but it may also result in mild hypoventilation.

Aged↗

PubMed1997

Angiotensin-converting enzyme inhibitors in preventing remodeling and development of heart failure after acute myocardial infarction: results of the German multicenter study of the effects of captopril on cardiopulmonary exercise parameters (ECCE).

Early action of angiotensin-converting enzyme (ACE) inhibitors after myocardial infarction (MI) has been shown in large scale clinical trials to reduce mortality over the first weeks. However, the mechanisms involved are yet unclear and several trials showed a tendency toward a small, albeit unexpected, rise in cardiogenic shock or mortality. Since cardiopulmonary exercise testing (CPX) has become a "gold standard" in assessing the severity of heart failure, we studied--after finishing a pilot trial--the effect of captopril versus placebo in 208 patients who were individually titrated (titrated dose, mean 46/69 mg/day after 7 days/4 weeks, respectively) in order to preserve their blood pressure in the acute phase of myocardial infarction; we followed the development of congestive heart failure (CHF) over 4 weeks by measuring oxygen consumption. After 4 weeks, overall oxygen consumption at the anaerobic threshold (VO2-AT; 13.7 vs 13.1), maximal oxygen consumption (VO2max 19.3 vs 18.9 mL/kg per min) and exercise duration (896 vs 839 sec) showed a nonsignificant difference in favor of the captopril group. The predefined, categorized, combined endpoint of severe heart failure or death (heart failure necessitating ACE inhibition, VO2max < 10 mL/kg per min, or death) was significantly reduced in the captopril group (n = 7/104) versus placebo (n = 18/104; p = 0.03). Differences were mainly caused by fewer CHF events (delta n = 10). We conclude that ACE inhibition with individualized dose titration markedly reduces the 4-week incidence of severe heart failure or death; > 10 patients per 100 treated gained major benefits from this therapy.

Adult↗

PubMed1997

[Anemia increases work of breathing in patients with lung disease].

BACKGROUND: Pulmonary diseases with marked disorders in gas exchange or chronic overload of the respiratory pump needs increased ventilatory requirements. Additionally in these patients anemic may aggravate the ventilatory load. We thereby evaluated whether in these patients treatment of anemia (red blood cell transfusion: RBCT) leads to an improvement of the ventilatory load in comparison to the anemic patients without pulmonary disease. PATIENTS AND METHODS: We examined 21 patients with an anemia (Hb < 11 g%, 12 men). Fifteen patients had a pulmonary disease (group A), 6 patients suffered from anemia without pulmonary disease (group B). Subsequently within 8 hours the patients got 2 to 3 RBCT. We studied the patients on the day of admission and 24 to 36 hours after transfusion. The patients kept bed rest for spontaneous breathing 1 hour prior to the actual examination without supplemental oxygen. Hemoglobin, hematocrit, respiratory rate, respiratory minute volume and arterial blood gases were measured. On the following day we repeated the same procedures. RESULTS AND CONCLUSIONS: Anemia in patients with an increased ventilatory requirement causes an additional increase of work of breathing. In these patients-in contrast to patients without compromised lungs-2.2 red blood cell transfusions lead to an impressive reduction of VE (about 20%) and correspondingly also to a reduction of WOB.

Aged↗

PubMed1997

[Endoscopic placement of an intratracheal oxygen catheter--description of a new method].

BACKGROUND: In patients with disturbed gas-exchange intratracheal oxygen insufflation improves oxygenation and reduces the minute ventilation. Until now the intratracheal oxygen insufflation was performed using a tracheostomy or a percutaneous transtracheal technique. We studied the acceptance and efficacy of the intratracheal oxygen insufflation using a bronchoscopic technique of intratracheal catheter placement. PATIENTS AND METHODS: Five COPD-patients (4 men, 55.2 +/- 10.3 years; FEV1: 0.9 +/- 0.31 = 30.3 +/- 5.5% debit, pO2: 56.2 +/- 10.3 mmHg, pCO2 +/- 43.1 +/- 4.8 mmHg). Procedure of catheter placement: Through a nasally passed bronchoscope a guide wire was inserted into the proximal part of one bronchus. When positioned at the point 2 to 3 cm proximal to the carina, the bronchoscope was marked with plaster at the nasal ostium in order to measure this distance. After removing the endoscope, the oxygen catheter was inserted proximal to the carina using the guide wire. Before and during the intratracheal oxygen insufflation (flow: 3 l/min) minute ventilation, tidal volume, breathing frequence, blood gases and the subjective scores (using a visual analogue scale) were measured. RESULTS: Apart from one patient with a tolerable spontaneous declining urge to cough irritation the catheter was tolerated well during the study. Whereas pCO2 remained stable during the ITO2 (before ITO2: 43.1 +/- 4.8 mmHg; after 1 hour ITO2: 44.3 +/- 4.8 mmHg), the oxygenation improved (pO2: 56.2 +/- 10.3; 81.4 +/- 19.6 mmHg) and the minute ventilation decreased (7.5 +/- 1.8; 5.4 +/- 1.3 l/min) by approximately 28%. CONCLUSION: The bronchoscopic application of the intratracheal oxygen catheter was characterized by high acceptance, low invasiveness and immediate function. Furthermore, the minute ventilation and work of breathing respectively decreased to a relevant degree.

Adult↗

PubMed1997

[Value of various intra- and extraoral therapeutic procedures for treatment of obstructive sleep apnea and snoring].

BACKGROUND: Recently intra- and extraoral devices are increasingly used in order to treat obstructive sleep apnea (OSA) and snoring. We examined the value of some devices according to the literature and our own results. PATIENTS AND METHODS: The mandibular advancing devices aim at increasing upper airway diameter. The active part of the tongue extending device (SnorEx) is a stamp connected to a piston which exerts pressure at the base of the tongue causing its forward displacement; we studied 23 patients. The principle of an optically stimulating system ("eye-cover", Snore-Stop) consists of a microphone and light diods which are integrated in the eye-cover. After detecting acoustic signals (for example snoring) optical stimuli are generated in front of the eyes, which are thought to induce arousals causing a change of body position and the reduction of the snoring and apneas; we measured 24 patients. The principle of the tongue-retainer (Snore-Master) is the fixation of the tongue in a ventral position, which is thought to enlarge the mesopharyngeal area; we studied 14 patients. The nose plaster (Breathe-Right) contains an elastic spine that pulls the alae nasi cranial. This manipulation is thought to increase the diameter of the nostril and reduce the airway resistance. We measured 30 patients with obstructive sleep apnea and 20 snoring subjects without obstructive sleep apnea. RESULTS: Regarding the mandibular advancing due to different appliance designs and study protocols variable success rates have been documented. In patients with mild to moderate obstructive sleep apnea a reduction of the sleep related breathing disorder could be shown. Non compliance (NC) to the tongue extending device was 75% (17/23). Non-compliance-patients were characterized by unacceptable local-side-effects of the prosthesis, lacking improvement of symptoms and of the respiratory disturbance index. Both tongue-retainer and -extensor are characterized by a high incidence of local side effects. Neither the eye-cover nor the nose plaster could improve the severity of obstructive sleep apnoe or snoring. In contrast to another study we could not show a significant effect of the tongue-retainer. CONCLUSIONS: Neither the nose plaster nor the optical stimulating device influenced the degree of obstructive sleep apnea and snoring. There are conflicting data regarding the tongue retainer. The high rate of non-compliant subjects and the low efficacy of the tongue extending prosthesis precludes large-scale use of this treatment modality in patients with obstructive sleep apnoe and snoring. In selected individuals suffering from a mild to moderate degree of obstructive sleep apnea with CPAP-inefficiency and -incompliance the mandibular advancing principle may be an therapeutic alternative to CPAP.

Equipment Design↗

PubMed1997

Screening for renal carcinoma associated mutations in the von Hippel-Lindau tumor suppressor gene by temperature gradient gel electrophoresis.

Renal cell carcinoma is the most common neoplastic disease of the adult kidney and occurs in its sporadic and hereditary form. Approximately 57% of all renal carcinomas of the clear cell type analyzed revealed a mutation in the von Hippel-Lindau disease (VHL) gene. In the present work, temperature gradient gel electrophoresis (TGGE) is presented as a rapid and precise polymerase chain reaction (PCR)-employing methodology for the detection of mutations in the VHL gene. The theoretical efficiency of TGGE to detect mutations in every base pair of the gene was calculated. According to computer analysis, at least 92% of all known mutations in the VHL gene are detectable. This calculated figure appears to be in agreement with the experimental results. Primary difficulties in analyzing exon 1 of the VHL gene were overcome by the employment of psoralen-cross-linked PCR fragments. In addition, TGGE analysis was used in screening for possible mutations in thirteen renal carcinoma samples. With this protocol TGGE is successfully added to the array of methods for the screening of VHL mutations.

Aged↗

PubMed1997

Endoscopic placement of a tracheal oxygen catheter: a new technique.

OBJECTIVE: In patients with chronic obstructive pulmonary disease (COPD), intratracheal oxygen insufflation (ITO) is an established therapeutic approach. We developed a new endoscopic technique of intratracheal catheter placement. The aim of this pilot study was to demonstrate its short-term feasibility in acutely extubated patients with moderate to severe COPD who require oxygen therapy. DESIGN: A guide wire was inserted through a nasally passed bronchoscope and was positioned such that its tip was placed intratracheally. Using a "Seldinger technique", the tracheal catheter was then inserted over the wire to a point 2-3 cm proximal to the carina and positioned under direct vision from the bronchoscope inserted through the contralateral nose. After catheter insertion, the guide wire was removed. The patients scored catheter-associated local discomfort using a visual analogue scale. In a randomly assigned, crossover design, the effectiveness of the endoscopically (e) inserted ITO catheter was assessed by measuring the capillary blood gases, respiratory rate (RR), tidal volume (Vt) and minute ventilation (MV) after 1 h breathing room air without eITO and 1 h after eITO (flow: 3 l/min). MEASUREMENTS AND RESULTS: The eITO catheter was placed in all patients without complications and with only minimal discomfort in two patients (spontaneously reversible cough). Compared to breathing room air, capillary O2 pressure increased (from 54.7 +/- 9.4 to 82.8 +/- 21.8 mmHg) whereas Vt (from 458.7 +/- 86.8 to 358.3 +/- 75.1 ml) and MV (from 7.7 +/- 1.5 to 5.5 +/- 1.1 l/ min) decreased significantly (each p < 0.0001) with eITO in all patients. The capillary CO2 pressure and RR did not change. CONCLUSIONS: Acutely extubated patients in whom oxygen therapy is indicated may profit from eITO. This new technique works immediately and is thus an effective short-term intervention of potential value in the intensive care unit.

Bronchoscopy↗

PubMed1997

[Temperature changes of the cornea by applying an eye bandage].

BACKGROUND: The corneal temperature is not often measured, but it may be useful to evaluate the temperature-changing effect of the application of eye bandages. The reason for applying an eye bandage is to calm an inflamed eye and to provide mechanical protection. Everyone knows that some patients have more complaints after an eye bandage has been applied. This phenomenon might be caused by the inflamed eye being warmed up by bandage application. MATERIALS AND METHODS: In 40 apparently healthy subjects 24 +/- 1.93 years of age we examined the temperature changes caused by two different types of eye bandage. The measurements were done with a Jeol infrared camera. Twenty probands received a monocular bandage consisting of a perforated plastic cap and another 20 subjects a monocular mull bandage with a perforated plastic cap. RESULTS: The mean corneal apex temperature was 32.05 +/- 0.74 degrees C. Both bandages caused the corneal temperature to go up considerably. The perforated plastic cap increased the mean apex temperature by 0.58 +/- 0.48 degree K and the combined mull bandage by 1.15 +/- 0.57 degrees K (P < 0.05). CONCLUSIONS: Application of an eye bandage increases the corneal temperature significantly. This is known to change enzyme activities and to cause prostaglandin liberation and pain. A change in the bacterial spectrum may result. Cooling as a universal principle in antiphlogistic therapy might be a supplementary therapy in treating sterile, but inflamed eyes.

Adult↗

PubMed1997

[Eyelid reconstruction with tarsomarginal transplant].

UNLABELLED: In the past 3 years, 85 basal cell carcinomas were treated in our clinic using eyelid reconstruction. During the same period, 54 lids were reconstructed after other diseases, mostly after chemical burns. In one of the 54 patients, the upper lid was reconstructed using a tarso-marginal graft after congenital coloboma. METHOD: In 31 of the 85 patients with basal-well carcinoma (36%), so much tarsus was lost that a transplantation of tarsus was necessary. Fifteen of the 31 patients were treated with a Hughes-plasty and 16 using a tarsomarginal graft, two in the upper lid. RESULTS: In eight of the remaining 16 cases, the defect was less than one half of length, so that the graft was taken from the second lower lid. In the remaining eight patients, the defect was two thirds of length or longer. In six cases, a 7 mm-graft was taken from the upper lid. As the tarsus from the upper lid measures 10 mm and is thus twice as big as the lower lid tarsus, it was divided into two grafts, resulting in two grafts measuring 7 x 5 mm. They were placed in the lower lid ("double tarsomarginal graft"). The former lower part with lashes was placed in the middle of the lower lid, the former upper part peripherally. In two patients, the defect was healed with three tarsomarginal grafts. A pedicle skin flap was transposed to cover the posterior grafts. Remaining defects were closed with free skin transplants. CONCLUSION: The tarsomarginal graft permits a short operation time and early rehabilitation of the patients. The disadvantage of the double tarsomarginal graft is that the more valuable upper lid tarsus is used to reconstruct the less valuable lower lid tarsus.

Adult↗

PubMed1997

A new tongue advancement technique for sleep-disordered breathing: side effects and efficacy.

We examined the efficacy and the acceptance of an oral device (SnorEx) causing a forward displacement of the tongue for the treatment of sleep-disordered breathing (SDB). Twenty-three consecutive subjects with SDB were investigated. Noncompliance (NC) of use of the oral appliance was observed in 74% (17 of 23) of the subjects. NC patients were characterized by unacceptable local side effects of the prosthesis, lacking improvement of indicators of daytime well-being, and a missing reduction of the respiratory disturbance index (RDI). The device was tolerated without side effects in 26% (6 of 23) of the subjects. In these compliant (C) subjects the RDI, EDS, and snoring improved significantly (p < 0.05) compared with baseline values. After 6 mo using the device, five of the six C patients were still using it. We conclude that the high rate of noncompliance and the low efficacy of the SnorEx prosthesis preclude large-scale use of this treatment modality in patients with SDB and snoring since the local side effects are the principal cause of NC. No useful predictive parameter of treatment compliance or treatment success was found. Thus, this dental appliance should be prescribed only for selected patients failing other treatment modalities seen by an experienced sleep-disorders specialist.

Dental Prosthesis↗

PubMed1997

[Optical stimulation method (Snore-Stop) and tongue retainer (Snore-Master) without relevance in therapy of obstructive sleep apnea and snoring].

Recently intra- und extraoral devices are increasingly used in order to treat obstructive sleep apnea and snoring. We examined the value of an optically stimulating system ("eye-cover", Snore-Stop) and a tongue-retainer (Snore-Master) as treatment of the obstructive sleep apnoe or snoring. In case of the eye-cover is a microphone integrated, which detects acoustic signals (e.g. snoring). After detection of snoring optical stimuli are generated in front of the eyes. This is intended to induce an arousal of the patient, without awaking him, causing a change of body position and this reduces the snoring or apneas. For the examination of the eye-cover in 26 patients (23 men, 55.6 +/- 10.3 years) polygraphic studies were performed while sleeping one night with the eye-cover and one night without, respectively. Visual analogue scales (VAS) were used in order to measure quality of life and sleep and the adverse effects of the device. To examine the tongue-retainer 14 patients (13 men, aged 52.9 +/- 11.8 years) were measured polygraphically. Again the subjective scores were assessed using the VAS. The principle of the tongue-retainer is to create a hollow space in front of the teeth, in which the tongue is positioned. Fixation of the tongue in this ventral position is thought to enlarge the mesopharyngeal area in order to reduce the upper airway obstruction. For both devices the index of snoring, the apnea-hypopnea-index, the index of desaturation, the mean and minimal SaO2 and SaO2 < 90 % in % of the night did not change significantly. Furthermore the subjective perception of the patients concerning their quality of sleep and life did not change. Moreover, despite of an adequate adaptation-period the use of the tongue-retainer was associated with considerable adverse effects. Neither the eye-cover nor the tongue-retainer could improve the severity of obstructive sleep apnoe or snoring.

Adult↗

PubMed1997

[Bronchial hyperreactivity and nCPAP therapy].

In patients with obstructive sleep apnoea (OSA) nCPAP may irritate the mucous membranes of the upper airways. We investigated in this study whether nCPAP can induce bronchial hyperreactivity (BHR). Forty-one patients (33 men, mean age 52.6 years) were treated with nCPAP due to OSA. All of them were tested for BHR with histamine ("pari-provo-Test") before and six weeks after initiation of the nCPAP therapy. Thirty-five of the patients showed BHR neither before nor after the beginning of CPAP. Six patients developed a BHR of moderate degree (PD20: 50-100 micrograms) during the study; four of these six patients were not symptomatic. The two other patients complained about more colds than usual or about noctumal cough. Both of them received inhaled steroids and a moistening system. Nobody of the enrolled patients was obliged to finish CPAP therapy due to BHR. Four patients had already a BHR before nCPAP therapy began. Most of the patients did not acquire a BHR during the first 6 weeks after nCPAP therapy had started. A BHR bronchial may develop, but in the majority it remains without clinical relevance. In patients with a BHR and OSA, the benefits of nCPAP therapy excel the potential adverse effects.

Airway Resistance↗

PubMed1997

[Is SnorEx also ApneaEx? A study with a new intra-oral prosthesis as a form of therapy of obstructive sleep apnea syndrome].

UNLABELLED: In recent years different kinds of dental devices have been advocated for treating sleep apnoea. In this study we report on our results with a kind of prosthesis ("Snor-Ex", DEPITA, 29336 Nienhagen) designed to relieve upper airway obstruction in sleep in pulling forward the tongue by a truss pad positioned in the posterior area of the tongue. We performed the study to test the effectiveness of the device in reducing the number of obstructive events. PATIENTS: 23 patients with OSA (22 male, age: 53.7 +/- 8.6 years, Body mass index: 31.1 +/- 3.9 kg/m2, Apnoea index: 33.5 +/- 18.4, Respiratory disturbance index: 45.6 +/- 19.7, mean apnoea duration: 20.4 +/- 4.4 sec) were included. STUDY DESIGN: Before the study was started, polysomnography was performed and the OSA associated symptoms/claims were standardised with the help of visual analogue scales (VAS). The prosthesis were made by the dental laboratory. Between the 28th and 42nd day after beginning with the study the patients had to come to the hospital for control. The effect of the therapy was documented only by a further polysomnography in patients who could sleep for at least 2.5 hours with the prosthesis. The effects of the device on changing OSA-associated symptoms and snoring were reevaluated by the above mentioned VAS. During the control the patients were divided into non-responders (NR) and responders (R) according to the results. RESULTS: The NR prevail in the study with 75% (17/23). They are characterised by inacceptable loco-regional side effects of the prosthesis, missing improvement of the state of daytime wellbeing and constant obstructive events. Only 25% of the patients are R. They locally tolerated the prosthesis, which is the precondition for long-term therapy. The severity of OSA diminished. Snoring also diminished significantly. CONCLUSION: According to our results the insufficient acceptance and the low effectivity of the SnorEx-prosthesis preclude large-scale indication for OSA patients. The prosthesis should not be prescribed without contacting a sleep lab.

Adult↗

PubMed1997

[Predictive value of laryngoscopy with reference to the severity of obstructive sleep apnea].

The diagnosis of sleep-related breathing disorders is based primarily upon targeted history-taking and upon night-time polysomnography. Diagnostic measures should be completed by laryngopharyngoscopy (LPS). Frequently in cases of relevant obstructive sleep-related breathing disorders, a collapse of the pharyngeal lumen may be detected already in the waking state: either during spontaneous breathing or through adequate provocation (snoring manoeuvre). Furthermore, endoscopy of the upper airways will yield indirect clues as to nocturnal snoring and possible obstructive apnoeas. Although the predictive value of LPS regarding the degree of obstructive sleep-related breathing disorders seems low compared with polysomnography, it appears reasonable to perform it to exclude further relevant ENT findings. With LPS, local and regional obstacles of the kind of the intended positive pressure ventilation (narrowing of the nasal ducts, septum deviation and hyperplasia of the turbinates) are demonstrable which may warrant surgical correction. LPS, which has a low complication rate, facilitates interdisciplinary cooperation in the care for patients suffering from obstructive sleep-related breathing disorders.

Airway Obstruction↗

PubMed1997

[Work of breathing in differentiation of various forms of sleep-related breathing disorders].

BACKGROUND: In contrast to the obstructive sleep apnoea syndrome (OSA) the obesity-hypoventilation syndrome (OHS) is characterised by persistent hypercapnia during the day and predominant hypoventilation during sleep. In this study we wanted to know whether work of breathing (WOB) in a sitting and supine position separates both groups. PATIENTS AND METHODS: OSA population: 20 men, 50.5 +/- 9.2 years, Body Mass Index (BMI: 54.1 +/- 6.9 kg/m2, pO2: 65.6 +/- 6.6 mmHg, pCO2: 40.6 +/- 3.1 mmHg, OHS-group: 14 patients, 13 men age: 53.1 +/- 9.3 years, BMI: 53.1 +/- 9.3 kg/m2, pO2: 51.8 +/- 10.5 mmHg, pCO2: 53.8 +/- 9.2 mmHg. The control group consisted of 10 normal weighted subjects. The intrathoracic pressures were assessed by an oesophageal catheter; at the same time, the minute ventilation (VE) and the breathing frequency (fb) were measured via a pneumotachygraph. The area under the pressure-volume loop was correlated to WOB. After reaching steady state VE, fb, and WOB were determined in sitting and supine position. RESULTS: In the OSA-group the apnoea index (AI) was 48.6 +/- 17.7/h and the respiratory disturbance index (RDI) was 66.3 +/- 19.4/h. The forced expiratory volume (FEV1) was 77.3 +/- 23% pred. and the vital capacity (VC) was 76.3 +/- 18.6% pred.; 7 out of 20 patients suffered from chronic bronchitis. In the OHS-group the AI was 21.5 +/- 19/h and the RDI 44.3 +/- 28.2/h. The majority of OHS patients had an airway obstruction (FEV1: 55.8 +/- 17.5% pred., VC: 58.8 +/- 12.8% pred.); 12 out of 14 patients suffered from chronic bronchitis. Compared to the OSA population WOB in the OHS group was significantly higher both in the sitting (0.67 +/- 0.28 J/I versus 1.04 +/- 0.32 J/I, p < 0.001) and supine positions (1.23 +/- 0.25 J/I versus 1.91 +/- 0.43 J/I, p < 0.001). Compared to the sitting position VE and fb did not change significantly in both groups lying supine. CONCLUSIONS: Compared to the OSA group at the same BMI the WOB of the OHS population was significantly increased in the sitting and supine position. The main reason for these findings may be the increased airway obstruction due to chronic bronchitis. Both populations did not change the breathing patterns during the different positions.

Adult↗

PubMed1997

[Nasal strips without effect on obstructive sleep apnea and snoring].

Recently a nose plaster (NP, Breathe-Right) has been increasingly used in the treatment of obstructive sleep apnoea (OSA) and snoring. Hence, we examined the use of the NP as a treatment of both OSA and snoring without OSA. The NP has a elastic spine that increases the diameter of the nostril and is thought to reduce the degree of OSA and snoring. According to the polysomnographic data two groups were differentiated: Group A (30 patients with OSA, apnoea index > 10/h, 26 men) and Group B (20 snorers, without OSA, 13 men). After the diagnostic polysomnography the efficacy of the NP was measured with a cardiorespiratory polygraph on the 2 following nights. In the group A the polygraphic data (apnoea index, time of apneas, desaturation index, time of desaturations, mean and nadir SaO2) were studied; in group B the snoring index (snoring events/hour) was measured. A questionnaire scored quality of sleeping, daytime condition and the quality of nose breathing. In neither group were the recorded polygraphic findings different with the NP although with the NP an improved nose breathing was scored in both groups. In group A 90% of the patients scored the daytime sleepiness unchanged and 10 of 30 patients described an improved quality of sleep. In group B there was no change in the frequency of snoring events with the NP. Neither the degree of OSA nor of snoring without OSA were changed by the NP, which can therefore not be considered a treatment of these conditions. However, the majority of the study population were impressed by the symptomatic improvement in nose breathing.

Dilatation↗

PubMed1997

[Changes in the time spent awake in obstructive sleep apnea and snoring--results of a pilot study].

Continuous positive airway pressure (CPAP) therapy reduces sleeping time per day and daytime sleepiness in obstructive sleep apnoea (OSA) and heavy snoring. Due to sleep fragmentation the OSA and heavy snoring are associated with a daytime sleepiness and increased necessity of sleep. In this pilot study the effect of CPAP-therapy on daytime sleepiness and sleep time during 24 hours were assessed in patients with OSA or heavy snoring (daytime sleepiness, none or slight apnoea with AHI < 10/h and benefit of CPAP). We studies 42 patients with OSA (AHI: 34.5 +/- 23.6) and 15 patients with heavy snoring: inclusion criteria: Patients with OSA (AHI > 10/h, ESS-Score > 8) and heavy snoring (AHI < 10/h, ESS-Score > 8) who were treated with nCPAP. Before and 2 months after initiation the CPAP-therapy all patients completed diary cards recording the sleeping time/day for 1 month; additionally they scored sleepiness using the Epworth sleepiness scale (ESS-score ranged from 0 to 24, the higher the score the worse the sleepiness) before and 2 months after initiation the CPAP-therapy. In the whole study population nCPAP-therapy reduced the sleeping time significantly by a mean period of 46 minutes per 24 hours (from 8.3 +/- 1.3 to 7.5 +/- 1.2 hours, p < 0.001) and improved the ESS score from 13.7 +/- 4.6 to 6.1 +/- 3.6 (p < 0.0001). In respect of the change of sleeping time/day and of the sleepiness score there was no significant difference between the OSA and heavy snoring group. With CPAP the AHI in OSA patients was reduced from 34.5 +/- 23.6/h to 3.2 +/- 3.2/h. Due to the improvement of sleep-related breathing disorders CPAP therapy reduced the mean sleeping time/day by approximately 10% and the daytime sleepiness score both in patients with OSA and heavy snoring compared to the pretreatment period.

Airway Obstruction↗