[Specular microscopy follow-up of endophthalmitis after cataract operation]

INTRODUCTION

Since the first reports of specular microscopic photographs in vivo of the corneal endothelium, endophthalmitis is said to damage endothelial cells irreversibly.

PATIENTS AND METHOD

We controlled 29 eyes 1 to 10 years after endophthalmitis following cataract surgery using specular microscopy. We tried to find out, if endophthalmitis leads to significant endothelial damage and we wanted to describe the in-vivo-cytological follow-up of the implanted lenses.

RESULTS

Endothelial cell-density of the eyes with endophthalmitis (n = 29) was 2733/mm2 (+/- 680). In those eyes receiving cataract-surgery without endophthalmitis in the fellow eye (n = 14), the endothelial density was 2851/mm2 (+/- 360). If the fellow eye has had no cataract surgery (n = 13), cell density was 3110/mm2 (+/- 750). Hypopyon-iritis after cataract-surgery did not decrease endothelial cell count significantly more than cataract-surgery without hypopyon-iritis (p > 0.05). At the last control at least one year after surgery, 36% of all IOLs were free of any cellular deposits. There was no case of a foreign-body-reaction.

CONCLUSION

In our patients, postoperative endophthalmitis has not led to significant endothelial damage. In none of our patients, endophthalmitis has led to chronic foreign-body reaction against the implant or to granulomatous uveitis. Specular microscopy of the corneal endothelium and of the implanted lens may help to differentiate in the case of postoperative inflammation between an infection and a foreign-body-reaction. In the case of a sterile foreign-body-reaction, there are no inflammatory cells on the endothelium or in the anterior chamber.

Silicone oil removal from a silicone intraocular lens with perfluorohexyloctane

Silicone oil can be easily dissolved in vivo from silicone intraocular lenses by perfluorohexyloctane. Using specular microscopy, we examined the corneal endothelium in a patient with silicone lens implantation immediately after cataract surgery and 5 weeks postoperatively. There were no signs of acute or chronic toxicity to the endothelium.

Survivin-deltaEx3 and survivin-2B: two novel splice variants of the apoptosis inhibitor survivin with different antiapoptotic properties

Recently, a novel antiapoptosis gene, i.e., survivin, was identified as a structurally unique member of the inhibitor of apoptosis protein family. Survivin expression is turned off during fetal development and not found in non-neoplastic adult human tissues but is again turned on in the most common human cancers. The antiapoptotic properties of survivin might provide a significant growth advantage in tumors and possibly also contribute to chemoresistance of cancer. Therefore, we analyzed the expression of survivin in human renal cell carcinomas (RCCs), known to be largely resistant to chemotherapy. Northern blot analysis and RT-PCR revealed survivin expression in newly established RCC cell lines (n = 11) of all major histological types. Moreover, we identified two novel splice variants of survivin, lacking exon 3 (survivin-deltaEx3) or retaining a part of intron 2 as a cryptic exon (survivin-2B). Both sequence alterations cause marked changes in the structure of the corresponding proteins, including structural modifications of the baculovirus inhibitor of apoptosis protein repeat domain. The role of the novel isoforms in the regulation of apoptosis was assessed in transfection experiments, showing conservation of antiapoptotic properties for survivin-deltaEx3 and a markedly reduced antiapoptotic potential for survivin-2B. In conclusion, our observations suggest a complex regulatory balance between the different isoforms of survivin, which might determine the response to proapoptotic stimuli, not only in human RCCs but also in fetal tissues and other types of cancer.

[Effect of intermittent ventilation on pulmonary hypertension in chronic respiratory failure]

Intermittent non-invasive (or nocturnal mechanical ventilation) eliminates symptoms of hypoventilation and improves gas exchange in patients with chronic respiratory failure. Performing right heart catheterisation we studied the influence of nocturnal mechanical ventilation on pulmonary hemodynamics. We investigated 20 patients with restrictive thoracic diseases (Post-TBC: n = 9, scoliosis: n = 11, PaCO2: 59.8 +/- 7.6 mmHg) and 13 patients with COPD (n = 13, PaCO2: 58.5 +/- 7.8 mmHg). All patients were mechanically ventilated in controlled mode. During the study the medication was not changed; COPD patients with long-term oxygen maintained this therapy. Right-heart catheterisation was performed immediately before and after 1 year nocturnal mechanical ventilation. In patients with thoracic restriction NMV induced a marked reduction of pulmonary artery pressure (PAP) from 33.2 +/- 10.0 mmHg before to 24.8 +/- 6.2 mmHg after 1 year nocturnal mechanical ventilation. In the COPD group PAP increased from 25.3 +/- 6.0 mmHg before to 27.5 +/- 6.0 mmHg after 1 year nocturnal mechanical ventilation. In contrast to the COPD group in patients with chronic respiratory failure due to thoracic restriction nocturnal mechanical ventilation causes substantial reduction in pulmonary artery pressure after a one year application.

[Scintigraphic demonstration of aspiration in long-term ventilation patients with tracheotomy]

The main complication of enteral feeding in prolonged mechanical ventilation via tracheostomy is the subsequent aspiration pneumonia. We used a scintigraphic method for the detection of enteral feeding aspiration and compared the results with clinical evidence of aspiration. The study population consisted of 62 consecutive tracheotomised patients (16 females, age: 64.1 +/- 11.1 years). The swallowing test was done in an upright or semirecumbent body position with the patients spontaneously breathing. The standard feed consisted of a liquid, semiliquid and solid meal which was labelled by 100 MBQ 99 TC. Scintigraphic aspiration (SA) was defined as positive if radioactivity was detected in the bronchial system. Clinical aspiration (CA) was defined as positive if there was cough, choking and distress after swallowing; furthermore, when receiving enteral feeding during suctioning or bronchoscopy. Both clinically significant aspiration (CA) and scintigraphic aspiration (SA) were found to be identical in 10 of 62 (16%) patients. CA, but not SA: 4/62 (6.5%). SA, but not CA (Subclinical aspiration): 4/62 (6.5%). Nor CA neither SA: 44/62 (71%) patients. Radiolabelled feed can be used as a feasible marker to detect aspiration. The test is a useful screening test and strategy to minimize aspiration. The scintigraphic method failed to identify all tracheotomised patients with clinically significant aspiration. However, scintiscanning did suggest that some patients had subclinical aspiration.

[Biocompatibility of flexible intraocular lenses in vivo]

PURPOSE

One aspect of biocompatibility of IOLs can be tested using specular microscopy of the anterior and posterior surface of the lens in vivo.

METHODS

We examined 45 patients after implantation of a "Memory lens" and 31 patients after the implantation of an "Acrysof" lens 3-6 months after surgery.

RESULTS

Typical deposits (Lens epithelial cells, spindle-shaped macrophages, giant cells, pigment, Wolter membrane) were rarely seen on both types of lenses. There were fewer lens epithelial cells on the posterior capsule and less secondary cataract after implantation of the "Acrysof" lens.

CONCLUSIONS

We did not find any indication of reduced biocompatibility in any of the lenses examined. The reduced rate of secondary cataract after implantation of the "memory lens" may be explained by the fact that this lens type sticks to the posterior capsule better.

[Retinal hemodynamics in patients with normal pressure glaucoma. Quantification with digital laser scanning fluorescein angiography]

Chronic ischemia of the retina and the optic nerve head seems of importance especially in patients with normal-tension glaucoma (NTG). The purpose of this study was to examine the retinal hemodynamics in patients with NTG.

PATIENTS

Twenty-five patients with NTG were examined (3 weeks washout period) in this study (age 58 +/- 16 years). The arteriovenous passage (AVP) time and arterial and venous diameters from scanning laser fluorescein angiograms were evaluated by means of digital image analysis.

RESULTS

The AVP time in patients with NTG (2.78 +/- 1.1 s) was significantly prolonged (P < 0.0001) compared with healthy subjects (1.58 +/- 0.4 s). No significant correlation was found between arterial and venous diameters, intraocular pressure, blood pressure or calculated perfusion pressure and retinal arteriovenous passage time.

CONCLUSION

Patients with NTG showed prolonged retinal passage, which could cause chronic hypoxia. This prolongation of circulation is not correlated with any of the clinical parameters. Thus, a circulatory defect might be a primary factor in the pathogenesis of NTG.

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.

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.

[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.

[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.

[Eyelid reconstruction with tarsomarginal transplant]

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.

[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.

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.

[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.

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

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.

[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.

[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.

[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.

[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.

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.

[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.

[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.