Biomedical subjects

D Henzler

Publications and source records attributed to D Henzler.

At least 19 recordsLinked to original sources

PubMed2007

[Coagulopathy in multiple trauma: new aspects of therapy].

Coagulopathy after trauma is a major cause for uncontrolled hemorrhage in trauma victims. Approximately 40% of trauma related deaths are attributed to or caused by exsanguination. Therefore the prevention of coagulopathy is regarded as the leading cause of avoidable death in these patients. Massive hemorrhage after trauma is usually caused by a combination of surgical and coagulopathic bleeding. Coagulopathic bleeding is multifactorial, including dilution and consumption of both platelets and coagulation factors, as well as dysfunction of the coagulation system. Because of the high mortality associated with hypothermia, acidosis and progressive coagulopathy, this vicious circle is often referred to as the lethal triad, potentially leading to exsanguination. To overcome this coagulopahty-related bleeding an empiric therapy is often instituted by replacing blood components. However, the use of transfusion of red blood cells has been shown to be associated with post-injury infection and multiple organ failure. In the management of mass bleeding it is therefore crucial to have a clear strategy to prevent coagulopathy and to minimize the need for blood transfusion.

Acidosis↗

PubMed2006

Influence of a 30-min break on divided attention and working memory in resident anaesthetists on daily routine.

BACKGROUND: The aim of this study is to test the hypothesis that a standard 30-min break in a routine 7.5 h period of work makes a difference in cognitive function. METHODS: In a double-blinded, cross-over trial 30 residents in anaesthesia were randomized to receive or not to receive a 30-min break between the assessment times of 07:30 and 14:00. in a normal working day. After at least 28 days the test was repeated with each resident in the opposite group. Primary outcome measure was the Test for Attentional Performance with the subtest of working memory and divided attention. Secondary outcomes are the Stanford Sleepiness Scale and the State-Trait Anxiety Inventory test. RESULTS: The sleep, caffeine and nicotine habits in both groups were comparable. There was no difference between the two groups in the Test for Attentional Performance, Stanford Sleepiness Scale and the State-Trait Anxiety Inventory. The correlation between recovery through sleep and sleep disturbance in the night before investigation to the Stanford Sleepiness Scale (P<0.001 and P=0.003) and State-Trait Anxiety Inventory (P<0.001 and P=0.001) at the 07:30 assessment is significant. For the 14:00 assessment the only significant correlation is between the recovery through sleep with the Stanford Sleepiness Scale (P=0.04) and the State-Trait Anxiety Inventory (P=0.05). CONCLUSION: A 30-min break during a 7.5 h daily routine did not influence cognitive function tests.

Adult↗

PubMed2006

Cardiopulmonary effects of intravenous prostaglandin E1 during experimental one-lung ventilation.

BACKGROUND: One-lung ventilation greatly improves operating conditions during thoracic surgery. Serious disadvantages of one-lung ventilation are hypoxaemia and increased pulmonary vascular resistance. Prostaglandins, like prostaglandin I2 (PGI2), are potent pulmonary vasodilators but may also influence venous admixture and systemic circulation. Since the lung is capable of extensive degradation of prostaglandin E1 (PGE1) but not of PGI2, PGE1 might affect systemic circulation to a lesser degree. Hence, we studied the effects of intravenous PGE1 on systemic and pulmonary circulation and on oxygenation during one-lung ventilation. METHODS: Lateral thoracotomy and cross-clamping of the left main stem bronchus was performed in twelve anaesthetised and ventilated pigs. Animals were cannulated with arterial, central venous and fast response thermodilution pulmonary artery catheters for haemodynamic measurements. PGE1 was administered with infusion rates of 25, 50, and 100 ng x kg (-1) x min (-1) during one-lung ventilation. RESULTS: All doses of PGE1 significantly decreased pulmonary vascular resistance and mean pulmonary artery pressure. However, a comparable significant reduction in systemic vascular resistance and mean arterial pressure was found. Arterial oxygen tension and venous admixture showed a slight but significant deterioration. Oxygen delivery remained unchanged or increased since the cardiac index increased. CONCLUSION: During one-lung ventilation in the pig, infusion of PGE1 significantly decreased pulmonary vascular resistance and pulmonary artery pressure but failed to achieve selective pulmonary vasodilation.

Airway Resistance↗

PubMed2005

Cardiopulmonary effects of iloprost in experimental acute lung injury.

Iloprost, a prostacyclin analogue with a prolonged plasma half-life has beneficial effects in chronic pulmonary hypertension, whereas the effects in acute lung injury (ALI) are unknown. The present study was performed to evaluate the cardiopulmonary effects of iloprost in experimental ALI. ALI was induced in 18 pigs by repeated lung lavage. Animals were randomised to controls, i.v. or inhaled iloprost for 15 min. Haemodynamics, gas exchange and ventilation-perfusion distribution were measured at the end of iloprost application and after 1 and 2 h. As a short-term effect, both i.v. and inhaled iloprost significantly decreased pulmonary artery pressure without major effects on gas exchange or systemic haemodynamics. After 1 and 2 h, a reduction of pulmonary hypertension was no longer present. As a long-term effect, inhaled, but not i.v., iloprost decreased pulmonary shunt and significantly improved gas exchange after 1 and 2 h. In conclusion, the single application of iloprost revealed short-term pulmonary vasodilation without other major cardiopulmonary effects. However, inhaled iloprost improved gas exchange due to a decrease of pulmonary shunt as a long-term effect, possibly as a result of a reduction of lung oedema formation.

Acute Disease↗

PubMed2004

[Extracorporeal membrane oxygenation by acute respiratory distress syndrome].

After various observational studies demonstrated a benefit of extracorporeal membrane oxygenation (ECMO) in the therapy of severe acute respiratory distress syndrome (ARDS), ECMO now represents an important contribution for ARDS therapy using clinical algorithms despite a lack of positive controlled studies. In specialized centers patients with severe ARDS and imminent hypoxia despite intensive conventional therapy, are treated with ECMO using blood pumps and artificial membrane lungs (oxygenators) for extracorporeal lung assist. The development of new surface modifications, optimized oxygenators and miniaturized blood pumps should increase hemocompatibility and lead to simplified treatment as well as less complications. New oxygenators with significantly decreased blood resistance allow the clinical application of pumpless arteriovenous extracorporeal lung assist (ECLA). After these new developments indications for ECMO could be extended from use not only as ultimate ratio but to less severe ARDS to enable lung protective, less invasive mechanical ventilation.

Anticoagulants↗

PubMed2004

[Treatment of acute respiratory distress syndrome in a treatment center. Success is dependent on risk factors].

SUBJECT: Mortality rates remain high for the acute respiratory distress syndrome (ARDS) despite standardised treatment algorithms. Little is known about prognostic factors and exclusion criteria for advanced treatment including extracorporeal membrane oxygenation (ECMO). METHODS: In an observational study design a cohort of 93 patients with severe ARDS admitted to a referral centre were analysed according to ventilatory and vital parameters. RESULTS: Overall survival rate was 70% and in patients who received ECMO treatment it was 67%. In patients exhibiting relevant co-morbidity the odds ratio for fatal outcome increased to 4.7 (95% CI: 3.3-24.9), and patients with multiple organ failure had a 7.5-fold increase (95% CI: 2.3-25.2) for risk of death. Survivors demonstrated a more pronounced improvement in oxygenation ( p<0.05) and CO(2) removal ( p<0.05) than non-survivors. CONCLUSIONS: Advanced treatment of ARDS including ECMO represents a therapeutic option if none of the currently considered contraindications are present. An improvement in gas exchange parameters, but not a defined value per se may be useful as a prognostic factor for favourable outcome.

Adult↗

PubMed2004

[Aerosolized and intravenous prostacyclin during one-lung ventilation. Hemodynamic and pulmonary effects].

BACKGROUND: One-lung ventilation is frequently used in thoracic surgery. However, hypoxic pulmonary vasoconstriction of the atelectatic lung may produce pulmonary hypertension. The objective of the present study was to compare the acute effects of intravenous versus aerosolized prostacyclin (PGI(2)) on pulmonary and systemic circulation. METHODS: PGI(2) was administered in 11 anesthetized and unilaterally ventilated pigs by infusion (5, 10, and 20 ng/kg body weight/min) and by inhalation (4, 8, and 16 ng/kg body weight/min) in a cross-over design. RESULTS: Infusion of PGI(2) reduced both pulmonary (PVR) and systemic vascular resistance (SVR). Due to a concomitant increase in cardiac index (CI) mean arterial (MAP) and pulmonary artery pressures (MPAP) did not change significantly. In contrast, aerosolized PGI(2) produced a significant decrease in PVR (-21.4 to -32.8%) and MPAP (-12.0 to -17.8%) without affecting SVR, MAP, and CI. Arterial oxygenation tension (p(a)O(2)) was not affected. CONCLUSION: During one-lung ventilation only aerosolized prostacyclin produced a selective pulmonary vasodilation.

Administration, Inhalation↗

PubMed2004

[Neuromonitoring with S-100 protein in the intensive care unit].

During the last years biochemical neuromonitoring with various molecules such as S-100 protein has become popular. A huge number of investigations both experimental and clinical have been undertaken to determine diagnosis and prognosis of patients with acute neurologic diseases. This article gives a review on the current knowledge, indications and limitations on the use of S-100 protein with regard to most of the acute neurological diseases an intensivist is confronted with in everyday practice.

Brain Injuries↗

PubMed2004

Factors independently associated with increased risk of pain development after ophthalmic surgery.

BACKGROUND AND OBJECTIVE: Little has been documented about the development of pain after ophthalmic surgery. This study was designed to assess the incidence and severity of postoperative pain following ophthalmic surgery, and to identify key factors independently associated with development of such pain. METHODS: In a prospective, observational cohort study, 500 patients undergoing elective ophthalmic surgery were examined by assessing numerical analogue scales and analgesic requirements. RESULTS: Depending on anatomical location of surgery, operations could be classified into creating 'more severe' or 'less severe pain'. Patients undergoing posterior segment, corneal and muscle surgery exhibited the highest numerical analogue scale scores (risk ratio 4.5, 95% CI 3.01-6.79, P < 0.0001). Anterior segment surgery, which per se did not create much pain, resulted in significantly more pain when performed under general anaesthesia compared to regional anaesthesia (risk ratio 6.52, 95% CI 2.33-18.2, P < 0.0001). No other factors independently associated with an increased risk of developing serious postoperative pain could be identified. CONCLUSIONS: Patients undergoing certain ophthalmic operations, especially if performed under general anaesthesia, are more likely to experience serious postoperative pain.

Adult↗

PubMed2004

[Pulmonary gas exchange: classical and modern findings].

The functional anatomy of the pulmonary gas exchanger enables an adequate oxygenation even in extreme situations, e. g. high altitude. An important mechanism is the distribution of ventilation and pulmonary perfusion. With induction of anaesthesia a relevant ventilation-perfusion mismatch results in oxygenation impairment, which can be prevented by specific anaesthetic techniques.

Anesthesia↗

PubMed2004

Modulating the pulmonary circulation: an update.

Pulmonary hypertension is a common finding in pulmonary circulatory disorders of different origin. Chronic pulmonary hypertension may develop due to either cardiopulmonary or systemic diseases whereas acute and acute-on-chronic pulmonary hypertension often occur in the course of cardiothoracic surgery. Right heart failure is the major risk particularly in the course of acute pulmonary hypertension. Thus, besides basic treatment of the underlying disease the use of vasodilators is a valuable therapeutic option to decrease right ventricular afterload, but intravenous vasodilators may provoke systemic arterial hypotension and impair gas exchange due to vasodilation of pulmonary shunt areas. Therefore, inhaled vasodilators such as nitric oxide and prostacyclin have been suggested for the treatment of pulmonary hypertension especially when concomitant hypoxemia is present due to a ventilation-perfusion mismatch. However, randomised controlled trials performed to evaluate long-term effects revealed different results: thus, in chronic pulmonary hypertension inhaled vasodilators improved outcome whereas the results for the treatment of the acute respiratory distress syndrome revealed beneficial effects only when used as a rescue and/or bridging therapy in severe hypoxemia. In cardiothoracic surgery, inhaled vasodilators have been shown to improve pulmonary circulation when severe pulmonary hypertension is present. Although effective in experimental studies no clear recommendation can be made in view to the use of other vasodilators such as phosphodiesterase inhibitors or endothelin antagonists. Likewise, the combination of different vasodilators merit further investigations to prove efficacy in randomised controlled trials.

Humans↗

PubMed2004

Anesthetic considerations in patients with chronic pulmonary diseases.

AIM: Increasing age and co-morbidities of patients admitted for surgery impose new challenges on the anesthesiologist. METHODS: Review of current literature regarding the perioperative management of patients with chronic pulmonary disease. RESULTS: If patients are treated adequately, surgery can be safely performed under regional and general anaesthesia. Major risk factors include type of surgery, type and duration of anesthesia, general health status and smoking history, but not certain lung function parameters. Regional anesthesia remains the first choice for intra- and postoperative care, and if general anesthesia is necessary, early extubation should be achieved. Non-invasive ventilation could be a possible alternative in weaning failure. CONCLUSION: Assessing the functional status of patients admitted to surgery remains a difficult task, and in patients identified at risk by clinical examination additional spirometry and blood gases may be helpful. If there are signs of respiratory failure, the anaesthetist should monitor the patient closely and invasively, yet there is no reason to deny any patient a substantially beneficial operation.

Anesthesia↗

PubMed2003

Survival of avian influenza virus H7N2 in SPF chickens and their environments.

The survival or clearance of the avian influenza virus (AIV) of subtype H7N2 in its chicken host was evaluated using experimentally infected specific pathogen free (SPF) chickens of different age groups. Birds of different ages were successfully infected with infectious doses ranging between 10(4.7) and 10(5.7) ELD50 per bird. In infected birds, the infective virus was undetectable usually by the third week following exposure. The infectivity or inactivation time of the H7N2 AIV in various environmental conditions was studied using chicken manure, heat, ethanol, pH, and disinfectants. The H7N2 AIV was effectively inactivated by field chicken manure in less than a week at an ambient temperature of 15-20 degrees C. At a pH 2, heating at 56 degrees C, and exposure to 70% ethanol or a specific disinfectant, the AIV infectivity was destroyed in less than 30 min.

Animals↗

PubMed2002

[The combination of retrobulbar block with general anaesthesia may lead to pre-emptive analgesia in patients undergoing pars plana vitrectomy].

SUBJECT: To determine whether additional regional blocking provides pre-emptive analgesia in patients undergoing elective pars plana vitrectomy. METHODS: In a prospectively randomised, double-blinded trial we investigated the potential benefit of combining regional anaesthesia (RA) with general anaesthesia (GA). In each group 25 patients undergoing pars plana vitrectomy were either done under GA (group A), GA combined with retrobulbar block (group B) or GA combined with peribulbar block (group C). Patients were examined by assessing NAS (numeric analogue scale). RESULTS: At all times, patients of group B experienced significantly less pain than patients in either group A or C (p < 0.001). There were no significant differences in pain scores between patients in groups A and C. Only 4 patients in group B required analgesics, whereas 17 patients in group A and 12 patients in group C. CONCLUSION: Certain ophthalmic operations are likely to cause postoperative pain when performed under GA alone, whereas the combination of retrobulbar block with GA reduces the development of pain as pre-emptive analgesia.

Adult↗

PubMed2001

Factors contributing to fatal outcome of traumatic brain injury: a pilot case control study.

OBJECTIVE: Patients with traumatic brain injury (TBI) have a high mortality and morbidity. This pilot study was undertaken to identify contributors to outcome in the early management of patients with TBI and to investigate the feasibility of a larger study. METHODS: Road trauma patients who died between January 1 and April 30, 2000 were selected from the Alfred Hospital's Intensive Care Traumatic Brain Injury database. These patients were matched with 2 survivors from the data base during the same period for age, injury severity score (ISS) and severity of brain injury using the head abbreviated injury score (head AIS). Patient injury scoring (using the revised trauma score, trauma and injury severity score and Glasgow coma score), arterial blood gas analysis, lactate concentration, inspired oxygen concentration, systolic and mean arterial blood pressure, intracranial pressure, intravenous fluid and blood transfusion volumes, body temperature, haemoglobin, white cell count, INR, APTT, temperature and plasma glucose, urea and creatinine concentrations were recorded for 48 hours from the time of injury. Time periods from the accident to key events (e.g. arrival of ambulance at accident scene, intubation, arrival at the emergency department, insertion of intracranial pressure monitor and primary surgery) were also recorded. RESULTS: Eighteen patients (6 deceased, 12 survivors) were identified. Despite matching, deceased patients had lower initial Glasgow Coma Scores (GCS) (3.6 vs. 7.4, P = 0.01) and lower revised trauma scores (4.41 vs. 5.75; P = 0.044) compared with survivors. There were no significant differences in other parameters. However, deceased patients tended to have longer times to treatment (P = NS) and experienced trauma at night more frequently, and survivors received almost double the volume of fluid resuscitation during the first 12 hours (19.7 +/- 19.1 vs. 11.8 +/- 2.7 mL/kg/hr, P = 0.513). CONCLUSIONS: Both initial GCS and severity of brain injury should be used to match TBI patients for injury severity in future studies. Lower initial GCS in deceased patients was likely due to greater severity of brain injury, although it is also possible that the lower GCS was due to decreased brain perfusion (perhaps reflecting inadequate resuscitation) in these patients. Volume of early fluid resuscitation, time to definitive therapy, and time of presentation to hospital may also be important determinants of patient outcome. A large case control outcome study is required to extend these observations.

Journal Article↗

PubMed1996

[A new procedure for determining leg length and leg length inequality using ultrasound. II: Comparison of ultrasound, teleradiography and 2 clinical procedures in 50 patients].

The clinical methods still in common use for measuring leg length and leg length discrepancy (LLD) cannot always meet the demands of precision and accuracy. A method using ultrasound is presented and shown to be a standardized, non-invasive method allowing accurate determination of leg length and LLD. Once the validity had been proved experimentally, practical handling, precision and accuracy of this method were tested on 50 patients in whom teleradiography of the lower extremity was performed for different reasons. The sonographically determined measures of LLD were compared with the radiographic measurements and in addition clinical measurements were taken by direct (tape measure) and indirect methods ("lengthening" of the shorter leg by wooden blocks of known thickness). Adjustments to the ventral hip joint and to the medial knee joint served as standardized, easily reproducible sonographic reference points. The mean variance of repeated sonographic measurements as a reflection of precision amounted to 3.5 mm2 for leg length measurement, with a maximum of 13.5 mm2. In the case of LLD the mean divergence between sonographically and radiographically determined LLD was 0.9 +/- 2.7 mm, with a maximum of 6.4 mm. The clinical methods with mean divergence of -1.2 +/- 9.6 mm (direct method) and -1.0 +/- 6.1 mm (indirect method) proved to be less accurate. The method examined for measuring leg lengths and LLD by means of ultrasound is easy to manage and non-invasive. Its precision and accuracy make it superior to clinical measuring methods and could even make some radiographical examinations superfluous.

Adult↗

PubMed1994

[A new procedure for determination of leg length and differences in leg length using sonography. I. Development and experimental studies].

The precise measurement of leg length and leg length discrepancies (LLD) plays an important role in the examination of lumbar spine and lower extremities. Those real LLD which may be posttraumatic or idiopathic, can sometimes hardly be differentiated from LLD caused by spinal scoliosis or malposition. Although there is no final agreement, to which extent a LLD becomes clinically significant, most authors state that clinical assessment of LLD by tape measure or lengthening of the short leg with blocks of known thickness is highly unreliable. Radiological methods are necessary for precise detection of LLD less than 10 mm. Since previously reported non-invasive, ultrasound-supported leg-length measurement methods proved to be complicated and unhandy, a new method was developed. To avoid radiation exposure accuracy and precision were tested on human cadavers and were compared to clinical assessments by tape measurement. A measurement device was constructed consisting of a wire rope meter and a length millimeter digital display. Measurements were taken with the examined person in supine position. The device was placed beyond their feet and the end of the rope was hinged with a metal brace to a convenient transducer in exact middle position. Thus the middle of the ultrasound monitor concords with the end of the rope. The medial knee joint and ventral hip joint were used as standardised sonographic landmarks. Ten not pre-selected mortants were measured in this manner and additionally clinical LLD was obtained with a tape measure (medial ankle to anterior superior iliac spine). Afterwards all distances were anatomically prepared and measured with a meter stick.(ABSTRACT TRUNCATED AT 250 WORDS)

Equipment Design↗

PubMedDate not supplied

[NHL-BFM 90 therapy study in treatment of malignant non-Hodgkin's lymphomas in children and adolescents. Part 1: Classification and allocation to strategic therapy groups. BIF study group].

One of the goals of the study NHL-BFM 90 was to investigate the distribution and prognosis of the different subtypes of Non-Hodgkin's Lymphoma (NHL) in children and adolescents according to histological, cytomorphological and immunological characteristics. From 4/1990 to 12/1992, 346 patients (pts) (84 females, 262 males) were enrolled (median age: 9.1 years; range: 0.8-17.9 years). Histology was available from 290 pts (84%), cytomorphology from 155 (44%), and immunophenotyping from 245 (70%). Cases with L1 oder L2 cytomorphology according to the French-American-British Classification were classified as lymphoblastic lymphoma and those with L3 cytomorphology as Burkitt-Type lymphoma or acute B-cell leukemia (B-ALL) if a histological classification was not available. By means of the combined analysis of all three diagnostic criterias the classification of the NHL according to the updated Kiel-classification was possible in 312 cases: 49% were classified as Burkitt-type-lymphoma (incl. B-ALL), 22% als lymphoblastic lymphoma, 10% as large cell anaplastic lymphoma (LCAL), 6% as centroblastic lymphoma, only few cases were classified as NHL of other subtypes, 3 pts (1%) suffered from low grade malignant lymphomas, and in 34 pts (10%) the NHL was not further classified. Patients were stratified according to NHL-subentities in 3 branches (Non-B-NHL, B-NHL, LCAL) of different treatment modalities. The estimated probability of a 3-year event free survival (pEFS) was 88 +/- 2% for the whole group (follow up 7 to 40 months, median 23 months) while pEFS of different subtypes was: lymphoblastic lymphoma: 91 +/- 4%; Burkitt-type-lymphoma/B-ALL: 90 +/- 2%; centroblastic lymphoma: 94 +/- 6%, LCAL: 88 +/- 6%. We conclude that the stratification of treatment modalities in study NHL-BFM 90 according to biological entities provided patients of different NHL-subtypes an equal chance to survive event free. The efficacy of the treatment strategy for rare subtypes, however, is not evaluable yet.

Adolescent↗