Bone Turnover in Patients with Chronic Kidney Disease Stage 5D and Healthy Controls - a Quantitative [18F]Fluoride PET Study.

BACKGROUND: Chronic kidney disease (CKD) is prevalent in the aging population and increases the risk of fracture 2-4 times. We compared optimized quantitative [18F]fluoride PET/CT methods to the reference standard with arterial input function (AIF) to identify a clinically accessible method for evaluation of bone turnover in patients with CKD. METHODS: Ten patients on chronic hemodialysis treatment and ten control patients were recruited. A dynamic 60-min [18F]fluoride PET scan was obtained from the 5th lumbar vertebra to the proximal femur simultaneously with arterial blood sampling to achieve an AIF. Individual AIFs were time-shifted to compute a population curve (PDIF). Bone and vascular volumes-of-interest (VOIs) were drawn, and an image-derived-input-function (IDIF) was extracted. PDIF and IDIF were scaled to plasma. Bone turnover (Ki) was calculated with the AIF, PDIF, and IDIF and bone VOIs using a Gjedde-Patlak plot. Input methods were compared using correlations and precision errors. RESULTS: The calculated Ki from the five non-invasive methods all correlated to the Ki from the AIF method with the PDIF scaled to a single late plasma sample showing the highest correlations (r > 0.94), and the lowest precision error of 3-5%. Furthermore, the femoral bone VOI's correlated positively to p-PTH and showed significant differences between patients and controls. CONCLUSIONS: Dynamic 30 min [18F]fluoride PET/CT with a population based input curve scaled to a single venous plasma sample is a feasible and precise non-invasive diagnostic method for the assessment of bone turnover in patients with CKD. The method may potentially allow for earlier and more precise diagnosis and may be useful for assessment of treatment effects, which is crucial for development of future treatment strategies.

Dopaminergic Activity in Antipsychotic-Naïve Patients Assessed With Positron Emission Tomography Before and After Partial Dopamine D2 Receptor Agonist Treatment: Association With Psychotic Symptoms and Treatment Response.

BACKGROUND: Dopamine activity has been associated with the response to antipsychotic treatment. Our study used a four-parameter model to test the association between the striatal decarboxylation rate of 18F-DOPA to 18F-dopamine (k3) and the effect of treatment on psychotic symptoms in antipsychotic-naïve patients with first-episode psychosis. We further explored the effect of treatment with a partial dopamine D2 receptor agonist (aripiprazole) on k3 and dopamine synthesis capacity (DSC) determined by the four-parameter model and by the conventional tissue reference method. METHODS: Sixty-two individuals (31 patients and 31 control subjects) underwent 18F-DOPA positron emission tomography at baseline, and 15 patients were re-examined after 6 weeks. Clinical re-examinations were completed after 6 weeks (n = 28) and 6 months (n = 15). Symptoms were evaluated with the Positive and Negative Syndrome Scale. RESULTS: High baseline decarboxylation rates (k3) were associated with more positive symptoms at baseline (p < .001) and with symptom improvement after 6 weeks (p = .006). Subregion analyses showed that baseline k3 for the putamen (p = .003) and nucleus accumbens (p = .013) and DSC values for the nucleus accumbens (p = .003) were associated with psychotic symptoms. The tissue reference method yielded no associations between DSC and symptoms or symptom improvement. Neither method revealed any effects of group or treatment on average magnitudes of k3 or DSC, whereas changes in dopamine synthesis were correlated with higher baseline values, implying a potential effect of treatment. CONCLUSIONS: Striatal decarboxylation rate at baseline was associated with psychotic symptoms and treatment response. The strong association between k3 and treatment effect potentially implicate on new treatment strategies.

[The use of an inspiratory impedance valve during cardiopulmonary resuscitation does not improve long-term survival or neurologic outcome]. / Anvendelse af ventilsystem ved hjerte-lunge-redning bedrer ikke langtidsresultater.

The impedance threshold device (ITD) works by increasing negative intrathoracic pressure, venous return and cardiac output during cardiopulmonary resuscitation. Although animal studies have shown promising results on haemodynamics, randomized studies and metaanalyses in humans have not shown better long-term survival or neurologic outcome. No studies have been done on the use of the ITD during in-hospital cardiac arrest. The ITD combined with active compression-decompression cardiopulmonary resuscitation may result in a better outcome.

Effect of high perioperative oxygen fraction on surgical site infection and pulmonary complications after abdominal surgery: the PROXI randomized clinical trial.

CONTEXT: Use of 80% oxygen during surgery has been suggested to reduce the risk of surgical wound infections, but this effect has not been consistently identified. The effect of 80% oxygen on pulmonary complications has not been well defined. OBJECTIVE: To assess whether use of 80% oxygen reduces the frequency of surgical site infection without increasing the frequency of pulmonary complications in patients undergoing abdominal surgery. DESIGN, SETTING, AND PATIENTS: The PROXI trial, a patient- and observer-blinded randomized clinical trial conducted in 14 Danish hospitals between October 2006 and October 2008 among 1400 patients undergoing acute or elective laparotomy. INTERVENTIONS: Patients were randomly assigned to receive either 80% or 30% oxygen during and for 2 hours after surgery. MAIN OUTCOME MEASURES: Surgical site infection within 14 days, defined according to the Centers for Disease Control and Prevention. Secondary outcomes included atelectasis, pneumonia, respiratory failure, and mortality. RESULTS: Surgical site infection occurred in 131 of 685 patients (19.1%) assigned to receive 80% oxygen vs 141 of 701 (20.1%) assigned to receive 30% oxygen (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.72-1.22; P = .64). Atelectasis occurred in 54 of 685 patients (7.9%) assigned to receive 80% oxygen vs 50 of 701 (7.1%) assigned to receive 30% oxygen (OR, 1.11; 95% CI, 0.75-1.66; P = .60), pneumonia in 41 (6.0%) vs 44 (6.3%) (OR, 0.95; 95% CI, 0.61-1.48; P = .82), respiratory failure in 38 (5.5%) vs 31 (4.4%) (OR, 1.27; 95% CI, 0.78-2.07; P = .34), and mortality within 30 days in 30 (4.4%) vs 20 (2.9%) (OR, 1.56; 95% CI, 0.88-2.77; P = .13). CONCLUSION: Administration of 80% oxygen compared with 30% oxygen did not result in a difference in risk of surgical site infection after abdominal surgery. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00364741.

[Alcoholic ketoacidosis and lactic acidosis]. / Alkoholisk ketoacidose og laktatacidose.

Alcoholic ketoacidosis (AKA) and alcoholic lactic acidosis (ALA) are metabolic disorders which occur in alcoholics after an episode of binge drinking and subsequent abrupt termination of alcohol and food consumption. Abdominal pain, nausea and vomiting trigger the biochemical changes resulting in metabolic acidosis with increased anion gap. Other symptoms are tachycardia, hypotension and tachypnea. Untreated AKA and ALA can cause sudden unexpected death. The following is an account of a patient who after hip surgery developed severe lactic acidosis and died.

Perioperative oxygen fraction - effect on surgical site infection and pulmonary complications after abdominal surgery: a randomized clinical trial. Rationale and design of the PROXI-Trial.

BACKGROUND: A high perioperative inspiratory oxygen fraction may reduce the risk of surgical site infections, as bacterial eradication by neutrophils depends on wound oxygen tension. Two trials have shown that a high perioperative inspiratory oxygen fraction (FiO(2) = 0.80) significantly reduced risk of surgical site infections after elective colorectal surgery, but a third trial was stopped early because the frequency of surgical site infections was more than doubled in the group receiving FiO(2) = 0.80. It has not been settled if a high inspiratory oxygen fraction increases the risk of pulmonary complications, such as atelectasis, pneumonia and respiratory failure. The aim of our trial is to assess the potential benefits and harms of a high perioperative oxygen fraction in patients undergoing abdominal surgery. METHODS AND DESIGN: The PROXI-Trial is a randomized, patient- and assessor blinded trial of perioperative supplemental oxygen in 1400 patients undergoing acute or elective laparotomy in 14 Danish hospitals. Patients are randomized to receive either 80% oxygen (FiO(2) = 0.80) or 30% oxygen (FiO(2) = 0.30) during surgery and for the first 2 postoperative hours. The primary outcome is surgical site infection within 14 days. The secondary outcomes are: atelectasis, pneumonia, respiratory failure, re-operation, mortality, duration of postoperative hospitalization, and admission to intensive care unit. The sample size allows detection of a 33% relative risk reduction in the primary outcome with 80% power. DISCUSSION: This trial assesses benefits and harms of a high inspiratory oxygen fraction, and the trial may be generalizable to a general surgical population undergoing laparotomy. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00364741.