Search PubMed⌕ Search

Biomedical subjects

A Deller

Publications and source records attributed to A Deller.

At least 19 recordsLinked to original sources

Continuous haemofiltration with r-hirudin (lepirudin) as anticoagulant in a patient with heparin induced thrombocytopenia (HIT II).

A 60-year-old man was admitted to the hospital with aortic dissection. An operative excision and replacement with a Y-graft was performed. Postoperatively he developed multiple organ dysfunction and required intermittent haemofiltration (anticoagulation with heparin). An ischemia of the left leg occurred at the third postoperative day. The initial platelet count was 99,000/microliter. Continuous haemofiltration (CVVH) was started three days later. Thrombotic obstructions of haemodialysis filters and catheters occurred frequently and heparin-induced thrombocytopenia (HIT II) was suspected. Antibodies against heparin were found in the HIPA test. Despite heparin free citrate dialysis and anticoagulation with danaparoid thrombotic obstructions of filters and catheters continued. Therefore the anticoagulation therapy during CVVH was changed to recombinant hirudin (lepirudin). Starting dose was a bolus of 0.01 mg/kg bw followed by the same amount as maintenance dose per hour. Anticoagulation was adjusted to an increase of aPTT (activated partial thromboplastin time) to 1.5-2 times its normal value. A dose of 0.005 mg/kg bw/h lepirudin was sufficient to maintain adequate anticoagulation. After changing to lepirudin no further catheter obstructions were observed and the platelets recovered slowly. Renal function improved and five weeks after admission endogenous creatinine clearance showed a value of 25 ml/min. We conclude that lepirudin is an effective anticoagulant during CVVH in patients with HIT II. In partly permeable polysulfon filters a dose of 0.005 mg/kg bw/h lepirudin is sufficient to maintain adequate anticoagulation. Monitoring anticoagulation by measuring the increase of aPTT (factor 1.5-2.0) seems to be safe. However, optimally the r-hirudin concentration should be measured directly using the Ecarin clotting time.

Aortic Dissection↗

[Early and long-term results of percutaneous dilatation tracheostomy (PDT Ciaglia) in 195 intensive care patients].

PURPOSE: Tracheostomy is frequently required in the treatment of critically ill patients to prevent the complications associated with prolonged translaryngeal intubation. Tracheostomy may facilitate airway suctioning and improve patient comfort in the process of weaning. The purpose of the study was to assess our experience with PDT and to evaluate the complications in comparison with open surgical tracheostomy which is associated with complication rates ranging up to 50%. METHODS: PDT was performed using the serial dilational technique described by Ciaglia (percutaneous tracheostomy introducer set, Cook Critical Care) by careful fibreoptic monitoring of the tracheal puncture and the tracheostomy tube insertion. Complications related to the procedure and late effects were recorded. RESULTS: 195 PDT were performed in adult intensive-care patients on prolonged mechanical ventilation. In 182 cases (93.4%) placement of the tube was successful without complications. Intraoperative complications occurred in 13 patients (6.6%) including bleeding (5), superficial lesion of the tracheal mucosa (3), pneumothorax (1) and others (4). After decannulation in 132 patients the tracheostoma closed spontaneously and the cosmetic and functional results were good. In 131 cases there was no clinical, radiographic and endoscopic evidence of symptomatic tracheal stenosis. Only in one patient 6 weeks after decannulation a relevant stenosis was seen. In 72 patients after median sternotomy no stomal wound infection and no mediastinitis was observed. CONCLUSIONS: PDT is a safe and practicable alternative technique which can be performed in the intensive-care unit with a lower risk of complications than open surgical tracheostomy. Endoscopic guidance prevents serious complications and apparently increases the safety of this procedure.

Adolescent↗

[The elimination of carboxyhemoglobin--gender-specific and circadian effects].

We investigated sex-specific and circadian variations of carboxyhemoglobin (COHb) elimination in healthy volunteers. COHb elimination follows an exponential function with a baseline found in nonsmoking women at 1.72% and in nonsmoking men at 1.79% COHb saturation. During the day, the elimination half-life time (t1/2), determined by eleven hourly samples after stopping smoking was significantly (Wilcoxon-test, p less than .01) shorter in women (3.2 +/- .4 hours, mean +/- standard deviation, n = 7) than in men (4.5 +/- 0.4, n = 6). During the night, too, t1/2 calculated from 2-point measurements after the smoking halt was significantly (Wilcoxon-test, p less than .05) shorter in women (4.3 +/- 1.1, n = 4) than in men (8.0 +/- 1.6, n = 5). In men, t1/2 during the night was significantly longer (p less than .01, Wilcoxon-test) than during the day. The day/night difference may be caused by reduced alveolar ventilation during sleep. Less muscle mass and, therefore, less myoglobin as a depot for carbon monoxide may account for the shorter half-life time of carboxyhemoglobin in women. We conclude that these variations of COHb-elimination should be taken into account when a smoking halt is advised, for instance, preoperatively.

Carboxyhemoglobin↗

[Carboxyhemoglobin in smokers and a preoperative smoking cessation].

The proportion of carbon monoxide-haemoglobin (COHb) in blood was determined before elective surgery on 50 patients (12 women and 38 men; mean age 39.5 [21-68] years) who were smoking at least 20 cigarettes a day, at two moments: during ad lib smoking and after a smoking halt of more than nine hours. 50 nonsmokers (25 women and 25 men; mean age 29.5 [20-48] years) served as controls. COHb proportion before smoking halt averaged 6.9 +/- 1.8%, after halt it averaged 3.8 +/- 1.1% (P less than 0.001). Individual values over 6% were found even after abstinence. COHb proportion in nonsmokers was 1.8 +/- 0.2% (nonsmokers vs. smokers: P less than 0.001 with and P less than 0.01 without smoking halt). The results show that measures to improve oxygen transport capacity, such as blood transfusion or oxygen breathing, are indicated early, especially in an emergency, in smokers and those with uncertain smoking habits. Smoking halt of at least nine hours should be recommended to all heavy smokers before elective surgery.

Adult↗

The consequences of continuous haemofiltration on lung mechanics and extravascular lung water in a porcine endotoxic shock model.

Endotoxinaemia (E. coli endotoxin, 0.111.B4) and pulmonary hypertension were evoked in 20 swine, randomly assigned to receive either zero-balanced venovenous haemofiltration (HF) with an ultrafiltration and replacement rate of 600 ml/h (HF group, n = 10) or to undergo an uninfluenced spontaneous course (E group, n = 10) during a constant infusion of endotoxin until the end of the experiment. Endotoxin-induced pulmonary dysfunction was assessed on the basis of extravascular lung water (EVLW) using a thermo-dye technique via a fiberoptic intra-aortic probe, gas exchange and lung mechanics, the latter derived by a pressure-volume loop (P/V loop) of the respiratory system (super syringe, flow 30 ml/s, tidal volume 600 ml). A comparable increase in alveolo-arterial oxygen difference and a constant EVLW was observed in both groups. The progressive deterioration of hysteresis area and compliance parameters by endotoxinaemia was significantly blunted by HF. Independent of an impact on pulmonary oedema zero-balanced HF modifies endotoxin induced lung injury, probably by the convective transport of mediator substances.

Animals↗

[Carbomonoxyhemoglobin and methemoglobin in patients with and without a smoking history during ambulatory anesthesia. Consequences for the use of pulse oximetry].

Carboxyhemoglobin (COHb) and methemoglobin (MetHb) in venous blood were determined by oximetry in 1000 non-hospitalised preoperative patients. 370 of them were smokers (S), 630 non-smokers (NS). In addition, in five S we compared the oxygen saturation measured by pulse oximetry (SaO2, p) with that measured by in vitro oximetry (SaO2) and that calculated with reference to COHb (SaO2,korr). MetHb (0.66 +/- 0.21%, mean +/- standard deviation) was found to be of no relevance. COHb in S (5.12 +/- 2.25%, maximum 12.4%) was significantly higher than in NS (1.82 +/- 0.3%, range 0.9%-4.0%) and is therefore of importance in S for the oxygen transport and for the interpretation of SaO2, p, which overestimated SaO2 at a COHb level of 4.4 +/- 0.7% by 4.5 +/- 0.9%. The difference between SaO2, korr (calculated according to Forstner) differed from SaO2 by 0.66 +/- 0.5% only. We conclude that there is an indication for in vitro oximetry in non hospitalised smokers or cases of unknown smoking history. If oximetry is not available, both a reduction of O2-binding hemoglobin and an overestimation of SaO2 by pulse oximetry in an order of ten per cent should be taken into account. To compensate for dyshemoglobin fractions, pulse oximetry using more than two wavelengths is desirable.

Ambulatory Care↗

[Pneumonia prevention in long-term mechanically ventilated patients: selective skin decontamination according to Stoutenbeek or prevention of colonization according to Unertl? A prospective randomized comparison of both treatments].

In a prospective randomised study, the effects of two different colonisation prophylaxis techniques on colonisation and pulmonary infection were investigated in 40 critically ill patients with long-term ventilatory support (greater than or equal to 4 days). 20 patients were selectively decontaminated with 4 x 100 g polymyxin E, 4 x 80 mg tobramycin and 4 x 500 mg amphotericin B, administered through the gastric tube and with an antimicrobial sticky paste in the oropharynx (group I). 20 patients received 50 mg of polymyxin B and 80 mg of gentamicin dissolved in 10 ml of 0.9% saline at 6 h intervals into nose, oropharynx and stomach as well as 300 mg of amphotericin B in the oropharynx only (group II). All patients received cefotaxime systemically in the first 3 days. In group I gram-negative aerobic bacteria in the pharynx decreased from 35% to 0%, in group II from 40% to 10% and in the rectum from 80% to 61% (10% in the second week) in Group I and from 100% to 73% (33% in the second week) in group II. The decrease in gram-negative microorganisms was accompanied by an increase in the frequency of Staphylococcus epidermidis. In group I, two patients developed pneumonia and two patients urinary tract infections, in group II two patients suffered from pneumonia and 3 patients urinary tract infections. Both regimes are effective methods of prophylaxis for lowering colonisation with gram-negative aerobic bacteria and the frequency of pneumonia in patients requiring long-term mechanical ventilation. A possible selection of gram-positive bacteria must be appropriately monitored.

Adult↗

[The value of criteria for pneumonia in the diagnosis of a ventilated pneumonia].

Reliable diagnosis of pneumonia in ventilated patients is frequently difficult, since there is no single specific criterion. In the present study, the following diagnostic criteria for pneumonia were checked in 25 ventilated patients: 1. temperature over 38.5 degrees C, 2. leukocytosis over 12,000/mm3, infiltration in the x-ray, 4. positive auscultatory findings, 5. purulent tracheal secretion (TS), 6. positive bacteriological findings (TS). Diagnosis of bacterial pneumonia was assumed if in the bronchoalveolar lavage (BAL) the concentration of a plausible causative organism was greater than or equal to 10(4)/ml and the "Bacterial Index" (BI) was greater than or equal to 6 (16). 15 patients fulfilled more than four criteria for pneumonia. In all patients the concentration of bacteria in the BAL was greater than or equal to 10(4)/ml (median 10(6)/ml, BI: 10). 10 patients fulfilled less than or equal to 4 criteria of pneumonia. In three of the patients, BAL was sterile, in four cases organisms less than 10(4) were isolated; none of these patients received antibiotics and diagnosis of pneumonia was not confirmed in the further course of illness. In three patients, bacteria greater than or equal to 10(4)/ml were isolated (BI 9, 10, 13); they improved under adequate antibiotic therapy. We conclude from these results that "as a rule" more than four of the criteria of pneumonia specified above should be present for diagnosis of pneumonia in ventilated patients in a surgical intensive-care ward. If there is any doubt, BAL should be performed to confirm the diagnosis.

Adult↗

Hemodynamic effects of different ventilatory patterns. A prospective clinical trial.

We compared the hemodynamic effects of three different ventilatory patterns including two variations of the I:E ratio (2:1 and 3:1) and a PEEP-pattern with the MAWP being equal in all three patterns. The study was performed on 15 patients without lung or cardiovascular disease who were ventilated after elective abdominal surgery. Each of the patients was subjected to the three different pressure wave curves. The IPPV served as control. Hemodynamic measurements included TEE registration of the LV cross-sectional areas, diameters and wall thickness as well as arterial blood pressure and heart rate. As a result, we found no significant differences in the hemodynamic effects of all three patterns. Compared with IPPV, they showed a reduction of systolic and diastolic blood pressure, LV dimensions and systolic wall stress. Assessed with the end systolic quotient, LV contractility remained constant.

Abdomen↗

[Risk factors in nosocomial pneumonia in intensive care patients. A prospective study to identify high-risk patients].

Sixteen risk factors for nosocomial pneumonia were prospectively studied in 582 intubated patients in a surgical intensive care unit (ICU) to identify patients at particularly high risk. Overall, pneumonias developed in 94 of the patients (16%). Significant risk factors for pneumonia were mechanical ventilation for more than 72 h, impaired consciousness or co-operation, specific therapeutic interventions as a marker of severe underlying diseases (dopamine/dobutamine greater than or equal to 5 micrograms/kg.min, barbiturate therapy for treatment of elevated intracranial pressure, continuous i.v. antiarrhythmic or antihypertensive drugs), and pre-existing pulmonary abnormalities (P less than 0.001). The acquisition of postoperative pneumonia was further associated with male sex, ASA class IV and a history of smoking, but statistical significance was lost after stepwise logistic regression. Longer operative procedures, thoracic or upper abdominal surgery, longer preoperative hospital stay, low serum albumin concentration on admission, prior antibiotics, old age, obesity, low weight, malignant disease, and steroid treatment did not influence the incidence of pneumonia. In this study we were able to identify a subpopulation of intensive care patients at particularly high risk for pneumonia.

Adolescent↗

Serum phospholipase A2 in patients with multiple injuries.

Catalytic phospholipase A2 activity (CA-PLA2) and the concentration of immunoreactive pancreatic PLA2 (IR-PLA2) were measured in serum samples from 12 patients with multiple injuries (median Injury Severity Score: 41). CA-PLA2 was increased in all patients and positive correlations were found between the extent of the increase of CA-PLA2, mortality, and impairment of pulmonary function. IR-PLA2 values were slightly increased in the serum of nine patients with multiple injuries. Of these nine patients, eight had an additional blunt abdominal trauma. On the other hand, no relationship was found between IR-PLA2 and CA-PLA2 values. This finding was confirmed by immunoadsorption experiments with an antiserum to human pancreatic PLA2, which demonstrated that the increased serum levels of IR-PLA2 were not responsible for the increased CA-PLA2 values. The results suggest the existence of at least two immunologically different phospholipase A2 enzymes in sera of patients with multiple injuries.

Adolescent↗