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M Strüber

Publications and source records attributed to M Strüber.

At least 19 recordsLinked to original sources
PubMed2006

Pressure-controlled versus volume-controlled one-lung ventilation for MIDCAB.

One-lung ventilation is limited by hypoventilation and hypoxemia because of increasing airway pressure and intrapulmonary shunt. Previous clinical studies compared pressure-controlled versus volume-controlled ventilation during one-lung ventilation in patients with pre-existing pulmonary disease. We studied 50 patients undergoing thoracotomy and one-lung ventilation because of cardiovascular disease. After two-lung ventilation with volume-controlled ventilation, patients were divided randomly into two groups. In one group, ventilation was switched to pressure-controlled ventilation after starting one-lung ventilation. In the other group, volume-controlled ventilation was continued. Parameters of ventilation, pulmonary function and systemic and pulmonary hemodynamics were recorded. We observed, that peak airway pressure, dead space ventilation and arterial carbon dioxide partial pressure were significantly higher during volume-controlled ventilation. After one-lung ventilation patients with pressure controlled ventilation had lower alveolar-arterial oxygen tension difference and a higher arterial oxygen partial pressure with significant differences for those patients in the intensive care unit. We conclude that pressure-controlled ventilation may be useful to improve gas exchange and alveolar recruitment during one lung ventilation.

Coronary Artery Bypass↗
PubMed2005

Outcome following single vs bilateral lung transplantation in recipients 60 years of age and older.

AIMS: The significant shortage of donor organs in lung transplantation necessitates a careful selection of lung transplant recipients. The outcome of lung transplant recipients aged 60 years and older has not been analyzed systematically. METHODS: We retrospectively reviewed our experience with older recipients. Between January 1999 and July 2003, 248 patients underwent lung transplantation at our institution, of which 18 were aged 60 years and older (7.3%, range 60-66, mean 62 +/- 1.1). RESULTS: Eleven (61%) of the recipients 60 years and older received a single (SLTx) and seven (39%), a bilateral lung transplant. Donor age in the single transplant cohort was 30 +/- 4 years. It was 33 +/- 3 years in bilateral patients. Posttransplant ventilation time was significantly different among groups, with 282 +/- 32 hours after bilateral and 56 +/- 13 hours after transplant (P < .05). Also significantly longer was the length of the ICU stay in the bilateral group. First PaO2 in the ICU was not different among the two groups. The 1-year survival in the single transplant group was significantly better compared to the bilateral group with 73% versus 43%, respectively. CONCLUSIONS: The 1-year survival following lung transplantation in patients older than 60 years is markedly reduced compared to recipients under 60 years of age. If a lung transplant is considered in a recipient above the age of 60 years, a single transplant should be favoured. If that is not indicated, patients over 60 should be very carefully selected for bilateral transplant.

Aged↗
PubMed2004

The experience of the support person involved in a lung transplant programme: results of a pilot study.

UNLABELLED: In contrast to the high priority most transplant programmes give to the recipient's support system there is a paucity of studies referring to the experience of the respective support persons. This study sought to focus on the subjective burden of support persons and their unmet needs. METHOD: A questionnaire was designed for a cross-sectional study using numerical rating scales and fill-in-the-gap-items concerning subjective burden, stress symptoms, unmet needs, suggestions to improve the support person's situation. Participants were 39 relatives of adult transplant patients (22 cystic fibrosis transplant recipients, 17 recipients with other aetiologies) who had transplants 5 years ago (mean). RESULTS: The acute illness stage was rated as extremely stressful by most of the respondents. However, even during the rehabilitation period, one third described themselves as very stressed. Stress related symptoms at or post transplant were reported by 82% of respondents (more mothers than partners). Symptoms mostly referred to depressive and anxiety states. Most support persons had to tackle organizational difficulties in order to stay with the recipient and faced financial burdens not refunded by agencies. Support persons made suggestions to improve the recipient's situation and those of other support persons. Regarding the recipient their advice referred to enhanced information giving, aspects of communication and better access to psychosocial professionals. Regarding another support person they suggested to be well-informed beforehand and to remain optimistic. CONCLUSIONS: Mothers in this study seemed to be particularly vulnerable as support persons and thus deserve special attention. Few resources may be needed to achieve considerable benefit for the support person, such as arranging accommodation or identifying a team member to relate to.

Adult↗
PubMed2004

[Lung transplantation. Possibilities and limitations].

Lung transplantation is an option for patients with endstage pulmonary diseases without contraindications. Recent European studies showed a survival benefit for patients with cystic fibrosis, fibrosis and emphysema after lung transplantation. Early mortality has been reduced recently by surgical improvements. Life expectancy after lung transplantation has improved in recent years but is still lower than in patients with other solid organ transplantations. Quality of life is consistently improved but exercise tolerance keeps reduced in comparison to the normal population. Specific problems described in detail are frequent organ rejections and infections, airway problems and a high incidence of malignant diseases. 5-year survival after lung transplantation is in average 60%.

Comorbidity↗
PubMed2004

[Quality of life and exercise capacity in lung transplant recipients].

BACKGROUND: Quality of life in lung transplant recipients (LTR) is reported to be comparable with that of the general population. However, previous studies have shown that exercise capacity was reduced to 30 - 40 % of normal values. The purpose of this study was to investigate the gap between good self-reported quality of life and reduced exercise capacity in LTR, to describe possible correlations and to compare the results with those of a control group (CG). METHODS: 27 LTR 208 +/- 67 days after bilateral lund transplantation (16 male, 11 female; age: 46 +/- 10 years; body mass index: 24 +/- 3 kg x m (- 2), FEV (1) % 75 +/- 27 %) and 30 controls (17 male 13 female; age 47 +/- 15 years; BMI: 26 +/- 4 kg x m (- 2), FEV (1) % 103 +/- 15 %) performed cardiopulmonary exercise testing and were interviewed with the standardized German "Quality of life profile for chronic disease" self-rating questionnaire. RESULTS: Significant differences were shown in objective exercise related variables (peak oxygen consumption: LTR 15.1 +/- 1.8, CG 34.5 +/- 9.1 ml x min (- 1) x kg (- 1); p < 0,01); peak workload: LTR 1.0 +/- 0.2; CG 2.4 +/- 1.0 W. kg (- 1); p < 0.01); percentage of predicted workload: LTR 44 +/- 12, CG 115 +/- 33 %; p < 0.01). The rating of subjective quality of life in physical, psychological and social domains of LTR did not differ from values of the CG or of the general population (n = 1143). The quality of life in the physical domain correlated significantly with peak exercise capacity (LTR r = 0.44, p < 0.05; CG r = 0.37; p < 0.05). CONCLUSION: Patients 7 months after lung transplantation described their physical, social and psychological quality of life as equally good as the healthy control group. However, peak exercise capacity and oxygen consumption were markedly reduced. To improve physical capacity in the range of daily activities, an exercise training program should be offered to patients after lung transplantation.

Adult↗
PubMed2001

Combined exogenous surfactant and inhaled nitric oxide therapy for lung ischemia-reperfusion injury in minipigs.

BACKGROUND: The combined application of exogenous surfactant and inhaled nitric oxide was evaluated for prevention of ischemia-reperfusion injury of the lung. METHODS: Left lungs were selectively perfused in 18 minipigs in situ with cold preservation solution. After 90 min of warm ischemia, the lungs were reperfused and the right pulmonary artery and bronchus were ligated (control group, n=6). Exogenous surfactant was instilled via bronchoscopy during ischemia (surfactant group, n=6). In a third group, surfactant was applied, followed by administration of inhaled nitric oxide (surfactant+NO group, n=6). Hemodynamic and respiratory parameters were recorded for 7 hr, and bronchoalveolar lavage fluid (BALF) was obtained before and after reperfusion for measurement of surface tension, small aggregate/large aggregate ratio, protein and phospholipid contents, and a differential cell count. RESULTS: Control group animals survived for 3.7+/-1.4 hr. In both surfactant-treated groups, five out of six animals survived the observation period (P<0.001). Dynamic compliance of the lung was decreased in control animals (P<0.001). In the surfactant+NO group, arterial PO2 was higher than in both other groups (P<0.001). BALF cell count and histology showed reduced neutrophil infiltration in surfactant+NO-treated lungs. Surface tension assessed in BALF with a pulsating bubble surfactometer was severely impaired in control animals (gammamin, 14.82+/-9.95 mN/m), but maintained in surfactant-treated (gammamin, 1.11+/-0.56 mN/m) and surfactant+NO-treated animals (gammamin, 3.90+/-2.35 mN/m, P=0.02). CONCLUSIONS: Administration of exogenous surfactant in lung reperfusion injury results in improved lung compliance. The addition of inhaled NO improves arterial oxygenation and reduces neutrophil extravasation compared with surfactant treatment alone.

Administration, Inhalation↗
PubMed2001

Aerosolized iloprost for severe pulmonary hypertension as a bridge to heart transplantation.

Preexisting pulmonary hypertension in pediatric patients is associated with poor outcome after cardiac transplantation because of donor right ventricular dysfunction. To avoid a combined heart-lung transplantation in a 17-year-old patient, we used an intensified pretreatment with intravenous prostacyclin and dobutamine combined with an inhalative therapy with the aerosolized prostacyclin-analog Iloprost. With this regimen, the patient was hemodynamically stabilized for the waiting period of 21 days after which an uneventful cardiac transplantation was performed.

Adolescent↗
PubMed2001

Flush perfusion with low potassium dextran solution improves early graft function in clinical lung transplantation.

OBJECTIVES: We have previously demonstrated experimentally an amelioration of reperfusion injury of the lung after preservation using low potassium dextran (LPD) solution compared to Euro-Collins (EC) solution. Now we report on early graft function in 106 lung transplant recipients of LPD or EC preserved grafts. METHODS: Initial graft function was assessed by measurement of lung compliance and oxygenation index 2 h after transplantation. Length of stay on the intensive care unit and hours of mechanical ventilation were compared. Correlation of donor oxygenation, ischemic time, type of transplant, recipient age and sex as well as initial lung compliance and oxygenation with early postoperative course were calculated. RESULTS: Dynamic lung compliance was significantly (P<0.05) improved in the LPD group. PO(2)/fiO(2) was comparable in both groups (303+/-122 mmHg LPD, 282+/-118 mmHg EC). Mechanical ventilation was used for 321+/-500 h in the EC group and 189+/-365 h in the LPD group (P=0.006). Intensive care therapy was required for 17.2+/-23.7 days in the EC group and 10.4+/-16 days in the LPD group (P=0.012). Significantly higher lung function parameters were obtained in extubated recipients of LPD preserved grafts 2 weeks after TX. Thirty day graft survival was improved in the LPD group (P=0.045). In the EC group, 30 day mortality was 14.2 and 8% in the LPD group. CONCLUSIONS: A reduction of perioperative mortality and morbidity suggests that LPD solution has superior early graft function compared to lung preservation using EC solution.

Adolescent↗
PubMed2001

Homocysteine--a treatable risk factor for allograft vascular disease after heart transplantation?

Growing evidence suggests that elevated total plasma homocysteine (tHCY) levels are associated with cardiac allograft vasculopathy following heart transplantation. To assess the effect of folic acid supplementation on tHCY levels, we performed a prospective study in a cohort of 69 patients (7.0 +/- 3.2 years after heart transplantation; mean age, 55.0 +/- 9.6 years; 61 male) treated with 5 mg folic acid/day (n = 34) vs no medication (n = 35). Therapy with folic acid resulted in significantly decreased tHCY levels, from 22.6 +/- 9.6 micromol/liter to 17.3 +/- 5.5 micromol/liter (p = 0.001) within 3 months, whereas values in the control group remained unchanged. We conclude that folic acid supplementation (5 mg per day) provides a simple and effective measure to lower elevated tHCY levels in heart transplant recipients.

Aged↗
PubMed2000

Improved right ventricular function after intracoronary administration of a C1 esterase inhibitor in a right heart transplantation model.

OBJECTIVE: Myocardial injury from ischemia can be augmented after reperfusion due to proinflammatory events including complement activation, leukocyte adhesion, and release of various chemical mediators. It has been shown that intracoronary administration of a C1 esterase inhibitor (C1 INH) significantly reduces myocardial necrosis in an experimental model of ischemia. Our study addresses the question whether the most susceptible region of the heart for ischemic injury, the right ventricle (RV), can benefit from the protective effects of C1 esterase inhibition after transplantation. METHODS: To precisely control RV volume in vivo an isovolumic model was used in which the RV volume was regulated using an intracavity high compliance balloon inserted into donor hearts of domestic pigs (34+/-4 kg). After 4 h of ischemia, donor hearts were transplanted into recipient pigs (44+/-4 kg). Treatment groups, each with six animals, consisted of C1 INH treatment or control. After opening the cross clamp, the C1 INH group animals received 20 IU/kg body weight of C1 INH intracoronary over a 5 min period. The control animals received no drug therapy. The hearts were reperfused for 60 min, and thereafter the RV balloon volume was increased in 10 ml increments until RV failure occurred. These measurements were repeated after 120 min of reperfusion. RESULTS: There was no significant difference in maximal RV developed pressure between the two groups (after 1 h, 35.7+/-5.9 vs. 40.6+/-12.7 mm Hg; after 2 h, 41.5+/-10.7 vs. 46.3+/-15.2 mm Hg; for C1 INH and control animals, respectively). However, the RV could be loaded with a significantly higher volume after both 1 h (60.0+/-20.0 ml (C1 INH) vs. 46.7+/-13.7 ml (control) balloon volume, P<0.05), and 2 h of reperfusion (70.0+/-8.9 ml vs. 60.0+/-6.3 ml; C1 INH and control animals, respectively; P<0.05). CONCLUSIONS: Intracoronary administration of a C1 INH significantly improves right ventricular function in an experimental transplant model. Thus, inhibition of the classic complement cascade may be a promising therapeutic approach for effective protection of myocardium from reperfusion injury after transplantation.

Animals↗
PubMed2000

Low-potassium dextran solution ameliorates reperfusion injury of the lung and protects surfactant function.

OBJECTIVE: This study was designed to compare the effect of lung preservation with low-potassium dextran solution and Euro-Collins solution on reperfusion injury and surfactant function by using an in situ model of warm ischemia. METHODS: The left lungs of 6 minipigs were selectively perfused with Euro-Collins solution. In an additional 6 animals low-potassium dextran solution was used for flush perfusion. After 90 minutes of warm ischemia, the lungs were reperfused, and the contralateral pulmonary artery and bronchus were clamped. Hemodynamic and respiratory measurements were obtained for 7 hours of reperfusion. Surface tension of bronchoalveolar lavage and surfactant small and large aggregates were determined before perfusion (right lung) and after 2 hours of reperfusion (left lung). RESULTS: In the group receiving Euro-Collins solution, right heart failure developed within 215 +/- 39 minutes of reperfusion. An increase in minimal surface tension (P =.03), surfactant small aggregates/large aggregates ratio (P =.003), and bronchoalveolar lavage protein content (P =.012) were found after 2 hours of reperfusion. In the group receiving low-potassium dextran solution, all minipigs survived (P =.0001). Dynamic lung compliance (P =.034) and oxygen tension/inspired oxygen fraction ratios were higher (P =. 0001). Lung water content was lower (P =.049). The increase of minimal surface tension (P =.02) and bronchoalveolar lavage protein concentration (P =.015) were significantly less. CONCLUSION: Preservation of the lung with Euro-Collins solution leads to a reduction of physical surfactant function during reperfusion. Low-potassium dextran solution protects surfactant function and metabolism, thereby reducing reperfusion injury of the lung.

Animals↗
PubMed1999

Surfactant replacement in reperfusion injury after clinical lung transplantation.

BACKGROUND: Reperfusion injury remains a significant risk factor in the immediate postoperative course after lung transplantation. We report on our initial clinical experience of surfactant replacement in reperfusion injury after clinical lung transplantation. METHODS AND RESULTS: In 31 consecutive patients, lung (8 single lung, 16 bilateral lung) or heart-lung (7) transplantation was performed. In 6 patients, severe reperfusion injury developed and was treated with continuously nebulized surfactant. Compliance of the allograft increased 40 +/- 25 % within 3 h following treatment with surfactant. Alveolar arterial oxygen gradient decreased by 23 +/- 11 % after 3 h and by 35 +/- 20 % after 6 h. Normal graft function was reestablished within 1-3 days after transplantation. All treated recipients were extubated until the 6th postoperative day. The 30-day mortality for the 31 recipients was 3.3 %, the 1-year survival 84 %. CONCLUSIONS: Surfactant replacement may become a clinical method for treatment of reperfusion injury after lung transplantation.

Adult↗
PubMed1999

C1-esterase inhibitor in graft failure after lung transplantation.

Graft failure after lung transplantation may occur immediately after transplantation due to reperfusion injury or later due to rejection and infection. Although the pathological mechanisms are not completely known, the clinical findings are similar to the adult respiratory distress syndrome. In this condition, the blood coagulation contact system and the complement system are activated, leading to a capillary leak syndrome. Activation of the contact as well as the complement system is regulated by a common inhibitor, C1-esterase inhibitor (C1-INH). We report on two patients who received high doses of C1-INH for 2 days during graft failure either due to reperfusion injury immediately after transplantation or due to an acute rejection 2 months after double-lung transplantation. In both cases of graft failure, a capillary leak syndrome occurred with pleural effusions of 7 l to more than 10 l per day. In case 1 disturbance of gas exchange during severe reperfusion injury could not be treated effectively with other treatment modalities like nitric oxide ventilation or surfactant administration. With the use of C1-INH, pleural effusions reduced within 12 h, leading to normal graft function within 4 days. In the second recipient, acute rejection forced the use of extracorporeal membrane oxygenation (ECMO) within 24 h despite immunosuppressive therapy. After administration of C1-INH, pleural effusions reduced from 19 l per day to 300 ml within 3 days of treatment. ECMO was discontinued after C1-INH treatment and the patient extubated 2 weeks later. This experience indicates that C1-INH may play a role in the management of capillary leak syndrome after lung transplantation.

Capillary Leak Syndrome↗