Inter-hospital transfer of ECMO-assisted patients with a portable miniaturized ECMO device: 4 years of experience.

OBJECTIVES: Extracorporeal membrane oxygenation (ECMO) in patients with severe pulmonary failure is able to keep patients alive until organ regeneration, until shunting out for further diagnostic and therapeutic options or until transportation to specialized centers. Nonetheless, extracorporeal techniques require a high degree of expertise, so that a confinement to specialized centers is meaningful. Following from this requirement, the need for inter-hospital transfer of patients with severely compromised pulmonary function is rising. METHODS: We report about our experience with a portable ECMO system during inter-hospital air or ground transfer of patients with cardiopulmonary failure. RESULTS: The portable ECMO system was used for transportation to the center and in-hospital treatment in 36 patients with an average age of 53 years suffering from respiratory failure. Accordingly, the ECMO system was implanted as a veno-venous extracorporeal system. Pre-ECMO ventilation time was 5.2 (2-9) days. Twelve patients were transported to our institution by ground and 24 patients by air ambulance over a median distance of 46 km. With the assistance of the ECMO device, prompt stabilization of cardiopulmonary function could be achieved in all patients without any technical complications. Post-ECMO ventilation was 9.8 days. Weaning from the ECMO system was successful in 61% of all patients after a median device working period of 12.7 days; median ICU stay was 34 days and a survival rate of 64% of patients was achieved. Technical (8%) and device-associated bleeding (11%)/thromboembolic (8%) complication rates showed very acceptable levels. CONCLUSION: Our experience demonstrates that miniaturized, portable ECMO therapy allows location-independent, out-of-center stabilization of pulmonary compromised patients with consecutive inter-hospital transfer and further in-house treatment, so that sophisticated ECMO therapy can be offered to every patient, even in hospitals with primary healthcare.

[Perioperative Addisonian crisis]. / Perioperative Addison-Krise.

An Addisonian crisis marks an acute adrenocortical failure which can be caused by decompensation of a chronic insufficiency due to stress, an infarct or bleeding of the adrenal cortex and also abrupt termination of a long-term glucocorticoid medication. This article reports the case of a 25-year-old patient with Crohn's disease who suffered an Addisonian crisis with hypotension, hyponatriemia and hypoglycemia during an emergency laparotomy after he had terminated prednisolone medication on his own authority. This necessitated an aggressive volume therapy in addition to an initial therapy with 100 mg hydrocortisone, 8 g glucose and a continuous administration of catecholamines. Under this treatment regimen hemodynamic stabilization was achieved. Reduction of the administration of hydrocortisone after 3 days resulted in cardiovascular insufficiency which required an escalation of the hydrocortisone substitution.

Omeprazole impairs the absorption of mycophenolate mofetil but not of enteric-coated mycophenolate sodium in healthy volunteers.

In 2 crossover studies, 12 healthy volunteers (6 male/6 female) received a single oral dose of mycophenolate mofetil (MMF) 1000 mg or an equimolar dose of enteric-coated mycophenolate sodium (EC-MPS) 720 mg fasting with and without coadministered omeprazole 20 mg bid. The plasma concentrations of mycophenolic acid (MPA) and of the inactive metabolite mycophenolic acid glucuronide (MPA-G) were measured by high-performance liquid chromatography (HPLC). In addition, dissolution of MMF 500 mg or EC-MPS 360 mg tablets was determined using an USP paddle apparatus in aqueous buffer of pH 1 to 7. The bioavailability of MPA following administration of MMF or EC-MPS was similar except for the time to peak concentration, which was longer in the EC-MPS group. Concomitant treatment with omeprazole lowered significantly C(max) and AUC(12h) of MPA following administration of MMF. The pharmacokinetics of EC-MPS was not affected. Dissolution of MMF in aqueous buffer decreased dramatically at pH above 4.5. The EC-MPS tablet was stable up to pH 5. Above, EC-MPS was quantitatively disintegrated and MPS quantitatively dissolved. There is strong evidence that impaired absorption of MMF with concomitant proton pump inhibitors is due to incomplete dissolution of MMF in the stomach at elevated pH.

[Acute renal failure and sepsis : Just an organ dysfunction due to septic multiorgan failure?]. / Akutes Nierenversagen und Sepsis : Nur eine Organdysfunktion bei septischem Multiorganversagen?

Acute renal failure (ARF) is clinically defined as an abrupt, but in principle reversible deterioration of glomerular and tubular function. Regarding pathophysiology, ARF is caused by ischemic renal conditions and toxic mediators. Sepsis is the most common cause of ARF in the intensive care unit and ARF is an independent risk factor for lethality of septic patients. Interventions to protect the kidneys against ARF include preliminary optimization of renal perfusion by volume load with cristalloid solutions and the administration of vasopressors. Daily maximum permissible dosages for colloids should not be exceeded and hyperoncotic colloid solutions should be generally avoided. Dopamine in "renal dosage" is nowadays obsolete. Loop diuretics produce diuresis and can be beneficial to extrarenal organs by improving fluid homeostasis, however diuretics do not improve kidney function and outcome. Therefore, diuretics are not indicated for patients with imminent or existing ARF. Septic patients with ARF can be treated by intermittent and continuous forms of renal replacement therapy, whereas continuous convective and intermittent diffusive methods are equivalent when utilizing an ultrafiltration rate > or =20 ml/h*kg body weight or a therapeutic interval > or =3 times/week.

[Anaesthesia tube constriction. Small defect--serious effect]. / Narkoseschlauchstenose. Kleine Ursache--grobe Wirkung.

After a problem-free induction of anaesthesia for an elective aortocoronary bypass operation in a 64-year-old female patient, recurrent ventilation problems occurred. An externally intact but internally damaged anaesthesia tube caused an expiratory stenosis of varying extent. Based on this case, the safety of the algorithms for difficult ventilation, the knowledge necessary for a possible differential diagnosis, the necessity for knowledge on the alarm procedure of the anaesthesia apparatus, as well as strategies for risk reduction will be discussed.

[Cost comparison of different graft materials in femoropopliteal bypass: experience with G-DRG]. / Kostenanalyse verschiedener Bypassmaterialien in femoropoplitealer Position unter G-DRG-Bedingungen.

BACKGROUND: The German DRG classification refrains from medical accuracy of different surgical procedures by concentrating mainly on economic aspects. The process cost calculation of femoropopliteal bypass should as an example illuminate the charge of a surgical procedure under hospital conditions. METHODS: From 07/03 to 03/04 we analysed out of 71 peripheral arterial reconstructions 10 alloplastic grafts (PBP) and 10 autologous vein grafts (VBP) for femoropopliteal above-knee bypass through the process cost calculation. This required a classification of the procedure in different diagnostic and treatment sections (ward, intensive care, diagnosis, treatment (surgical procedure)). RESULTS: The average length of hospitalisation with VBP amounted to 12.2 +/- 3.6 (7-19) days, and with PBP to 14.0 +/- 8.0 (8-35) days. The duration of the surgical procedure was almost identical with 118 +/- 26 minutes (VBP) compared to 110 +/- 31 minutes (PBP), but in average 0.4 more assistants participated in VBP. One bleeding caused revision in VBP; one PBP led to extended length of hospitalisation because of wound complication. We diagnosed one asymptomatic bypass occlusion in VBP. The average total costs in VBP amounted to 4 368.10 euro (profit: 4 468.15 euro), in PBP to 5 069.50 euro (profit: 3 802.94 euro). CONCLUSION: The reconstruction of the superficial femoral artery with alloplastic or autologous vein graft is profitable in G-DRG. Although less medical staff in required in PBP the price of the prosthesis weakens the profit. The autologous vein graft shows furthermore a shorter length of hospitalisation. Further investigation into cost-effectiveness regarding long-term follow-up and patency rates could lead to consequences for the German health system.

Surgery for aortoiliac aneurysms in kidney transplant recipients.

With the increase of long-term survivors following renal transplantation, aorto-iliac aneurysms requiring surgical management may be encountered more often. Our experience with temporary shunts for renal transplant protection during aorto-iliac aneurysm repair is presented along with a literature review of all cases on the subject. Three male patients with a median age of 56 (range 50-61) years were operated on for a dissecting aneurysm of the common iliac artery in one, respectively abdominal aortic aneurysm in the two remaining patients. All patients had impaired transplant function preoperatively with a median serum creatinine level of 167 (range 134-202) micromol/L and a median blood urea nitrogen concentration of 15 (range 9-23) pmol/L. The intra- and postoperative course was uneventful in all patients. Median postoperative serum creatinine level and blood urea nitrogen concentration were 135 (range 123-151) micromol/L and 10 (range 9-11) pmol/L, respectively. Aorto-iliac surgery in renal transplant recipients can be performed without transplant protection. However, in patients with a deteriorated transplant function or if a prolonged aortic cross-clamp time is anticipated, renal allograft protection measures may be beneficial to prevent possible ischemic damage.

Calcium-activated potassium channels and nitrate-induced vasodilation in human coronary arteries.

In some but not all arterial beds, smooth muscle cell calcium-activated K+ channels (KCa channels) play a central role in the mediation of the vasodilator response to nitric oxide (NO) and other nitrates. We investigated the effect of nitrates on KCa channels in the relaxation of human coronary arteries by means of isometric contraction experiments in arterial rings. We also measured whole-cell currents in freshly isolated human coronary artery vascular smooth muscle cells via the patch-clamp technique. Sodium nitroprusside, diethylamine-nitric oxide complex sodium salt and isosorbide mononitratre completely relaxed rings preconstricted with 5 microM serotonin and produced dose-dependent relaxations of 5 microM serotonin-preconstricted human rings. The relaxations were inhibited by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-oxyl 3-oxide (10 microM), which neutralizes nitric oxide. The KCa channel blockers iberiotoxin (100 nM) and tetraethylammonium ions (1 mM) significantly inhibited SNP-induced relaxations of human coronary arteries. Moreover, in the patch-clamp experiments, SNP (1 microM) stimulated KCa currents and spontaneous transient outward K+ currents carried by Ca spark activated KCa channels. The SNP-induced (1 microM) KCa current was strongly inhibited by iberiotoxin (100 nM). These data show that activation of KCa channels in smooth muscle cells contributes to the vasodilating actions of nitrates and nitric oxide in human coronary arteries. This finding may have unique clinical significance for the development of antianginal and antihypertensive drugs that selectively target K+ channels and Ca sparks.

[Current therapeutic strategy in primary intestinal non-Hodgkin's lymphoma]. / Aktuelle therapeutische Strategie des primären Intestinalen Non-Hodgkin-Lymphoms.

Of all surgical interventions of intestinal non-Hodgkin's lymphomas 58% (15 or 26 patients) are performed in an emergency situation. In 42% of cases, examination by ultrasonography, endosonography, intestinoscopy. Sellink's enema, thoracic, abdominal/pelvic CT and bone marrow puncture could determine the stage preoperatively. This could also be done by examining the regional and juxtaregional lymph nodes or performing a liver biopsy intraoperatively. Crucial for the therapy is in all cases the adequate staging even in emergency situations. Only special knowledge of the intestinal non-Hodgkin's lymphoma can lead to the necessary stage-adapted multimodal therapy--operation/irradiation/chemotherapy.

Pulmonary vein clamping during cardiopulmonary bypass: enhancement of operative field visualization and myocardial hypothermia.

In certain diagnostic entities temporary occlusion of the pulmonary veins during cardiopulmonary bypass essentially eliminates the left ventricular return of blood. This, in turn, improves visualization of the operative field and enhances myocardial hypothermia by preventing rewarming of the left ventricle to the perfusate temperature. Two methods of easily accomplishing pulmonary vein clamping are described.

Clinical comparisons of methods of myocardial protection.

Currently, numerous methods are in use for myocardial hypothermia as a myocardial preservation modality for cardiac operations. During cardiac ischemia we have compared myocardial surface cooling with topical cold saline (Group I, N = 9), crystalloid cardioplegia plus topical cold saline (Group II, N = 8) and cardioplegia with a specially designed cooling jacket (Group III, N = 8) in patients undergoing aortic or mitral valve replacement, or both. Temperatures were assessed and recorded continuously in standardized locations for the right and left ventricular epicardium and endocardium. In Group I the rate of cooling was significantly slower than in the other two groups. Also, excessive gradients were developed across the left and right ventricular walls. In Group II the rate and depth of cooling were adequate and initial temperature gradients were eliminated. However, over the period of ischemia, significant rewarming occurred. In Group III temperatures were reduced rapidly and uniformly and maintained at or below 10 degrees C for the duration of the ischemic period. These differences are statistically significant (p less than 0.05). For optimal myocardial hypothermia, we recommend the following: separate cannulation of the superior and inferior venae cavae with caval snares; venting of the pulmonary artery (if inadequate, pulmonary vein occlusion or direct left atrial venting); induction of myocardial hypothermia with crystalloid or cold blood cardioplegia; and maintenance of hypothermia by the cooling jacket described herein. It is also desirable to continuously monitor temperatures of the right and left ventricular endocardial and epicardial surfaces.

[Physically handicapped pupils at a regular school - experiences of the school experiment "Lichtenau" (author's transl)]. / Körperbehinderte in der Regelschule -- Erfahrungen aus dem "Modell Lichtenau".

As an experiment in integration, the joint placement of physically handicapped and non-disabled pupils into the regular class settings of a school belonging to the Hessisch-Lichtenau experiment makes special social and educational measures necessary both at school and in the residential home. The main activities have to be directed towards scientific studies of existing problems and their practical solutions. The following article describes the problems arising from the integrational efforts and suggests possible solutions.

Electromyographic temporal analysis of gait: normal human locomotion.

The telemetered electromyographic (EMG) activity of pretibial muscles (tibialis anterior), triceps surae (lateral gastrocnemius), medial hamstring group and quadriceps (vastus lateralis) of 20 normal subjects was examined during locomotion. The ages of the subjects ranged from 8 to 72 years (mean, 37 years). A microswitch shoe was used to correlate the EMG activity with eight specific components of the gait cycle. Tibialis anterior showed two peaks of activity, the first at the swing-stance transition, the second at the stance-swing transition. Gastrocnemius showed a single peak of activity recorded during push-off. The medial hamstring showed its greatest activity during deceleration in the swing phase. Vastus lateralis demonstrated peak activity at the transition from swing to stance. The mean cadence was 106 steps per minute. Swing phase occupied 39.6% and stance phase 60.4% of the gait cycle.

Electromyographic temporal analysis of gait: hemiplegic locomotion.

The telemetered electromyographic (EMG) activity of quadriceps, hamstrings, triceps surae and pretibial muscles on the affected side of 20 adult hemiplegic subjects was examined during locomotion. The subjects ranged in age from 29 to 68 years (mean, 52.1). Duration of the lesions ranged from 1 month to 8 years: in 11 subjects the duration of the lesions ranged from 1 to 9 months (mean, 4.9 months), and in the remaining 9 subjects from 1 to 8 years (mean, 4 years 2 months). Shoes with five microswitches, two in the heel and three in the sole, were used to correlate the EMG activity with eight specific components of the gait cycle. The results of the study showed a loss of the phasic pattern associated with normal locomotion. The hemiplegic subjects showed the greatest activity in the period of midstance. Expressed as a percentage of the total cycle, the mean stance time of the paretic lower limb was 67% and the mean swing time was 33%. The unaffected lower limb showed a stance phase of 80% and a swing phase of 20%.

Clinical telemetry of EMG and temporal information during gait.

Multichannel telemetry has formed an integral part of the clinical assessment of children's walking problems. EMG signals and temporal information from foot switches are transmitted from a small belt-pack unit which provides almost complete freedom of movement for the child. Although patients with various crippling diseases have been studied, the investigation of problems resulting from cerebral palsy has been most valuable clinically. The effects of orthopaedic surgery to release or transfer muscles can be asssessed more positively and the causes of some unexplained gait patterns can be investigated more thoroughly.