Intermittent hirudin versus continuous heparin for anticoagulation in continuous renal replacement therapy.

BACKGROUND: Besides possible bleeding complications a further problem in anticoagulation during continuous renal replacement therapy (CRRT) is the development of heparin-induced thrombocytopenia type II (HIT II) where further anticoagulation with heparin is contraindicated. The application of continuous hirudin as alternative for heparin caused bleeding complications by comparable filter efficacy. Aim of this prospective-controlled pilot study was to compare the efficacy and safety of intermittent hirudin and continuous heparin for anticoagulation during CRRT in critically ill patients. METHODS: 26 patients receiving CRRT were randomly allocated to two groups: Heparin group (14 patients): continuous administration of 250 IU/h heparin, dose was adjusted in 125 IU/h steps with a targeted activated clotting time (ACT) of 180-210 s. Hirudin group (12 patients): initial bolus application of 2-2-5 microg/kg hirudin, dose was adjusted in 2 microg/kg bolus steps with a targeted ecarin clotting time (ECT) >80 s. Observation time was 96 hours. RESULTS: Measured filter run time was virtually longer for heparin. No bleeding complications were observed in the hirudin group, two bleeding complications in the heparin group. CONCLUSIONS: Intermittent hirudin can be used safely for anticoagulation in CRRT. However, the in tendency better filter survival for heparin elucidates the need for further investigations to find the right dosage equilibrium between filter clotting and bleeding complications.

Introduction of a three-dimensional anthropometry of the viscerocranium. Part II: evaluating osseous and soft tissue changes following orthognathic surgery.

BACKGROUND AND OBJECTIVE: Anthropometric measurements, described and assessed in Part I of this article were applied in dysgnathic patients. Diagnosis, surgical planning and follow-up were performed and soft tissue ratios quantified. MATERIAL AND METHODS: One hundred and seventy-five anthropometric measurements and 146 cephalograms of 100 patients were included. Forty-five patients were analysed before and after surgery. Ten randomly selected patients were re-measured directly by two investigators for reliability and validity assessment. RESULTS: Manoeuvres that expanded the facial skeleton such as maxillary or mandibular advancements or maxillary elongations generally had a greater soft tissue impact than setbacks or maxillary impactions. A 1.4% intra-observer and a 2.6% inter-observer error was apparent with anthropometry. Concordance of anthropometry with roentgenocephalometry (p<0.04) was found by paired t -test. CONCLUSION: The anthropometry allowed reliable and objective, independent calculation of cranial bone relations and soft tissue projection. It is also sensitive to facial asymmetry. Easy application, versatility and an economic price for the assessment of facial proportions, soft tissue ratios, operation planning and follow-up were obvious.

Introduction of a three-dimensional anthropometry of the viscerocranium. Part I: measurement of craniofacial development and establishment of standard values and growth functions.

BACKGROUND AND OBJECTIVE: The analysis of lateral cephalograms is based on many vague landmarks that vary intra- and inter-individually. Exposure to radiation and high-quality equipment are essential, while identical object positioning is almost impossible. Anthropometry as presented in the literature is time consuming and cannot reproduce cranial three-dimensionality. Poor landmark definitions and resilience of the soft tissue foster systematic measurement errors. We used few easily detectable and accessible landmarks that are closely related to underlying bone. The distances measured were visualized three-dimensionally. MATERIAL AND METHODS: Measurements from 540 volunteers were reconstructed. Reliability was assessed through repeated measurements. Corresponding distances were measured in lateral cephalograms taken the same day. RESULTS: The age- and sex-related mean values and 95%-percentiles were visualized as growth functions. The intra-individual relative error in anthropometry was 3.7%, in roentgenocephalometry 0.9%. The inter-individual error was 5.8% for anthropometry and 3.6% for roentgenocephalometry. CONCLUSION: Applied anthropometry as described in the paper is reliable and valid for measuring craniofacial growth, arriving at a diagnosis and 'monitoring' treatment results. The relative measurement error in anthropometry appear to be smaller than the systematic magnification and distortion found in lateral cephalograms.