Parathyroid hormone decline 4 hours after total thyroidectomy accurately predicts hypocalcemia.

BACKGROUND: The level of parathyroid hormone (iPTH) serum has been controversial in the prediction of postthyroidectomy hypocalcemia. Analysis of the decrease between preoperative and postoperative iPTH levels should be more accurate. Therefore, the aim of our study was to prospectively establish the reliability of the iPTH decrease for early diagnosis of postoperative hypocalcemia and to identify the patients who are not at risk for hypocalcemia. METHODS: A prospective study of 137 consecutive patients who underwent total thyroidectomy was performed. Serum iPTH level was measured preoperatively and 4 hours postoperatively (iPTH(H4)). The sensitivity, specificity, and positive and negative predictive values for the iPTH(H4) and for the iPTH decline were estimated by confidence interval from thresholds determined by ROC curve analysis. RESULTS: Thirty-nine patients developed hypocalcemia (28.5%). Patients who developed hypocalcemia had a significantly lower iPTH(H4) and a significantly greater iPTH decrease (P < .001). The thresholds enabling prediction of hypocalcemia were 19.4 ng/L for iPTH(H4) and 68.5% for iPTH decline. Sensitivity, specificity, and positive and negative predictive values for iPTH(H4) were 84.6%, 92.9%, 82.5%, and 93.8% (overall accuracy, 90.5%). iPTH decline was more accurate to predict hypocalcemia (sensitivity, 97.4%; specificity, 95.9%; positive predictive values 90.5%; negative predictive values, 98.6%; and overall accuracy, 96.4%). CONCLUSION: The decrease in iPTH is more precise than the iPTH(H4) alone and can accurately predict hypocalcemia after total thyroidectomy. Patients with a decrease in iPTH less than 68.5% can be discharged at postoperative day one without any supplementation. Patients with iPTH decline more than 68.5% should be administered calcium and vitamin D supplementation before symptoms appear.

Blood loss comparison during transurethral resection of prostate and high power GreenLight(™) laser therapy using isotopic measure of red blood cells volume.

BACKGROUND: Transurethral resection of the prostate (TURP) remains the gold standard in the operative management of symptomatic benign prostatic hyperplasia (BPH). The main morbidity of TURP is bleeding, which leads to clot retention and blood transfusion. Newer techniques have appeared, and photovaporization of the prostate (PVP) with the GreenLight™ laser has been developed to reduce the morbidity of bladder outflow surgery. Isotopic measurements of total red cell volume and total blood volume (BV) are a recommended reference technique to evaluate bleeding occurring during endoscopic ablation of the prostate. Here, we compare blood loss during PVP and TURP using an isotopic method. METHODS: Eighteen patients underwent PVP, and 20 patients underwent a TURP for symptomatic BPH by one surgeon. The two groups were comparable in demographic data; however, prostate volume was significantly higher in the PVP group. BV was measured pre- and postoperatively using the isotope technique. RESULTS: The total BV was measured to have increased by 362 mL in PVP group compared with a loss of 315 mL in TURP group (p=0.001). The difference in total red cell volume increased by 148 mL in PVP group compared with a loss of 216 mL in TURP group (p=0.005). CONCLUSIONS: Using the isotope method, we have shown a significant difference in postoperative blood loss between TURP and PVP. Our study is the first to use an isotopic method to measure the blood loss during PVP. This technique needs further standardization before being introduced into routine clinical practice.

Aerosolized gemcitabine in patients with carcinoma of the lung: feasibility and safety study.

BACKGROUND: We investigated the biodistribution, pharmacokinetics, safety profile, and feasibility of aerosolized gemcitabine (GCB) in patients with lung carcinoma. METHOD: Eleven patients with carcinoma localized in the lungs were studied in a dose escalation study of aerosolized GCB administered 1 day/week for 9 consecutive weeks. Safety data, scintigraphic assessment of the delivered dose and pharmacokinetic monitoring were analyzed. Patients were treated with doses of between 1 mg/kg and 4 mg/kg (dose in the nebulizer), using a new inhaler device (Aeroneb Pro with an Idehaler Chamber). RESULTS AND CONCLUSIONS: The total dose of GCB delivered to the patient's lung was 42±16% of the initial amount of dose in the nebulizer. Safety data showed no hematologic toxicity, nephrotoxicity or neurotoxicity. At 4 mg/kg, one patient experienced grade 4 pulmonary toxicity (bronchospasm), which was the dose-limiting toxicity. Grade 2 and 3 toxic effects included fatigue, vomiting, dyspnea, and cough. Overall response: minor response in one patient, stable disease in four patients, progressive disease in four patients. Pharmacokinetic data showed very low plasma GCB levels. Maximal plasma concentration was observed at the end of nebulization. Aerosolized gemcitabin was safe, with minimal toxicity, for patients with lung carcinoma.

Aerosol deposition in neonatal ventilation.

Lung deposition of inhaled drugs in ventilated neonates has been studied in models of questionable relevance. With conventional nebulizers, pulmonary deposition has been limited to 1% of the total dose. The objective of this study was to assess lung delivery of aerosols in a model of neonatal ventilation using a conventional and novel electronic micropump nebulizer. Aerosol deposition studies with 99mTc diethylenetriamine pentaacetate (99mTc-DTPA) were performed in four macaques (2.6 kg) that were ventilated through a 3.0-mm endotracheal tube (with neonatal settings (peak inspiratory pressure 12-14 mbar, positive end-expiratory pressure 2 mbar, I/E ratio 1/2, respiratory rate 40/min), comparing a jet-nebulizer MistyNeb (3-mL charge, 4.8 microm), an electronic micropump nebulizer operating continuously [Aeroneb Professional Nebulizer (APN-C); 0.5-mL charge, 4.6 microm], and another synchronized with inspiration [Aeroneb Professional Nebulizer Synchronized (APN-S); 0.5-mL charge, 2.8 microm]. The amount of radioactivity deposited into lungs and connections and remaining in the nebulizer was measured by a gamma counter. Despite similar amounts of 99mTc-DTPA in the respiratory circuit with all nebulizers, both APN-S and APN-C delivered more drug to the lungs than MistyNeb (14.0, 12.6, and 0.5% in terms of percentage of nebulizer charge, respectively; p = 0.006). Duration of delivery was shorter with APN-C than with the two other nebulizers (2 versus 6 and 10 min for the APN-S and the MistyNeb, respectively; p < 0.001). Electronic micropump nebulizers are more efficient to administer aerosols in an animal model of ventilated neonates. Availability of Aerogen's electronic micropump nebulizers offers new opportunities to study clinical efficacy and risks of aerosol therapy in ventilated neonates.