Dose recommendations for intravenous colistin in pediatric patients from a prospective, multicenter, population pharmacokinetic study.

OBJECTIVES: The aim of this study was to describe the population pharmacokinetics of intravenous colistin use in children and to propose optimal dosage regimens. METHODS: A prospective, multicenter, population pharmacokinetic (PPK) study was conducted. Phoenix 64 version 8.3 was used for the PPK analysis. Simulations were performed to estimate the probability of target attainment for patients achieving target plasma colistin average steady-state concentrations (Css,avg). RESULTS: A total of 334 plasma colistin concentrations were obtained from 79 pediatric patients with a median age (interquartile range) of 2.6 years (0.8-6.8 years); 73 (92.4%) were admitted to intensive care units. Colistin pharmacokinetics were adequately described by a one-compartment model with first-order elimination along with serum creatinine (SCr) as a significant covariate in colistin clearance. The simulation demonstrated that the recommended dose of 5 mg of colistin base activity (CBA)/kg/day resulted in 18.2-63.0% probability of achieving a target Css,avg of 2 mg/l. With a lower targeted Css,avg of 1 mg/l, colistin dosing with 7.5 mg and 5 mg of CBA/kg/day were adequate for children with SCr levels of 0.1-0.3 mg/dl and >0.3 mg/dl, respectively. CONCLUSIONS: SCr is a significant covariate in colistin clearance in children. Colistin dosing should be selected according to the patient's SCr level and the desired target Css,avg.

Successful treatment of a child with Schwartz-Jampel syndrome using rapid maxillary expansion and CPAP.

STUDY OBJECTIVES: We reported an 8-year-old male patient with Schwartz-Jampel syndrome, severe obstructive sleep apnea, constricted maxilla and moderate tonsillar hypertrophy. The syndrome is characterized by myotonia, skeletal dysplasia, and facial dysmorphism. METHODS: CPAP was initially prescribed, but he was not able to tolerate due to a high pressure setting. Rapid maxillary expansion alone reduced AHI to 10.4 events/h. RESULTS: When combined with CPAP, AHI is further reduced to 2.4 events/h. The patient has a better compliance with CPAP following rapid maxillary expansion therapy as the pressure setting decreased. CONCLUSIONS: This is the first report utilizing a combination of rapid maxillary expansion and CPAP therapy to successfully treat severe pediatric OSA.

Central venous catheterization related complications in Pediatric Intensive Care Unit at Queen Sirikit National Institute of Child Health.

BACKGROUND: Central venous catheterization (CVC) is an indispensable route of venous access in management of critically ill patients. Potential CVC related complications include mechanical and infectious complications. OBJECTIVE: To determine type, incidence and risk factor of CVC related complications in pediatric patients. MATERIAL AND METHOD: Prospective observational study of all patients who underwent CVC in pediatric intensive care unit (PICU) at Queen Sirikit National Institute of Child Health, over a 1-year period. RESULTS: The study included 137 patients, of whom 63.5% were males. The mean age was 36.7 ± 4.4 months. There were 204 CVC attempts with total indwell time of 2,002 days. The rate of mechanical complication was 19%, including failure to place catheter (9.3%), hematoma (4.9%), arterial puncture (2%) and pneumothorax (1.5%). Patient body mass index (BMI) > 30 kg/m2, internal jugular venous catheterization, and longer insertion time (> 30 minutes) were associated with high mechanical complication rates. The incidence density of catheter related blood stream infection (CRBSI) was 7.5/1,000 catheter-days. Femoral vein placement had significant higher incidence of CRBSI. CONCLUSION: CVC related complications are comparable to previous studies. Risk factors of mechanical complications include high BMI, internal jugular venous catheterization and longer insertion time. Femoral venous catheterization is the only risk factor for CRBSI.

Effects of temperature and time delay on arterial blood gas and electrolyte measurements.

OBJECTIVE: To determine the changes in pH, PaO2, PaCO2 and Na, K, Cl in arterial blood samples stored at room temperature or on ice, at 0, 15, 30, 45 and 60 minutes. MATERIAL AND METHOD: Arterial blood samples were collected in heparinized capillary tubes and stored at room temperature (24-26 degrees C) and on ice (0-4 degrees C). ABG and electrolytes were measured at 0, 15, 30, 45 and 60 minute intervals. RESULTS: There were significant decreases in the pH, PaO2, Na, Cl and significant increases in PaCO2 and K over time in both groups. The changes were greater and faster at room temperature. The significant decrease in pH over time was not found until 30 minutes at room temperature and 45 minutes on ice. There were significant decreases in PaO2, concurrent with significant increases in PaCO2 from 15 minutes onwards in both groups. Both Na and K exhibited a significant change at 60 minutes in the room temperature group. Significant decreases of Cl over time were not found until 15 minutes at room temperature, and 30 minutes on ice. CONCLUSION: For ABG and electrolytes analysis, the blood sample should be analyzed within 15 minutes and be stored at either room temperature or on ice.

Mycoplasma pneumonia in young children, 2-5 years of age.

BACKGROUND: Mycoplasma pneumoniae is one of the most common causes of childhood community-acquired pneumonia (CAP), particularly in school-age children. Information regarding this infection in pre-school age children is lacking. OBJECTIVE: To determine the prevalence of M. pneumoniae in young children aged under 5 years with CAP. MATERIAL AND METHOD: This prospective study was conducted at Queen Sirikit National Institute of Child Health (QSNICH), Bangkok, Thailand between December 2001 and November 2002. We enrolled children aged 2 to 5 years with a clinical and radiological diagnosis of CAP. Acute and convalescent sera were collected and measured by using a particle agglutination test. Polymerase chain reaction (PCR) assay for M. pneumoniae was detected from nasopharyngeal secretions. Criteria for diagnosis were defined as > or = 4-found rising of mycoplasma antibody or titer > or = 1:160 with positive PCR. RESULTS: Thirteen out of 113 CAP patients were diagnosed as mycoplasma pneumonia. Three of them were diagnosed by > or = 4-fold rising of mycoplasma antibody while another 10 patients were diagnosed by mycoplasma titer > or = 1:160 with positive PCR for M. pneumoniae. Clinical symptoms and signs of these 13 mycoplasma pneumonia in young patients were fever (85%), cough (92%), dyspnea (85%), diarrhea (15%), rales (85%), wheezing or rhonchi (46%), and skin rash (15%). Leucocytosis (wbc > 15,000/cumm) was found in 46%. Chest x-rays revealed interstitial infiltration (71%), patchy infiltration (29%) and no pleural effusion was detected. Choices of antibiotic were erythromycin (31%), beta lactam antibiotics (61%), and antibiotic was not prescribed in one patient (8%). Sixty-nine percent of the patients improved, while 31% did not, possibly due to the use of beta lactam antibiotics, or non use of antibiotics. CONCLUSION: Mycopalsma pneumonia is not uncommon in children aged 2-5 years with CAP. Clinical signs, symptoms and radiological findings are non-specific and cannot be differentiated from other causes of CAP.

Prevalence and clinical features of mycoplasma pneumoniae in Thai children.

OBJECTIVE: To determine the prevalence and clinical features of mycoplasma pneumoniae in Thai children with community acquired pneumonia (CAP). MATERIAL AND METHOD: Diagnosis of current infection was based on > or = 4 fold rise in antibody sera or persistently high antibody titers together with the presence of mycoplasma DNA in respiratory secretion. The clinical features were compared between children who tested positive for M pneumoniae, and those whose results were negative. RESULTS: Current infection due to M. pneumoniae was diagnosed in 36 (15%) of 245 children with paired sera. The sensitivity and specificity of polymerase chain reaction (PCR) in diagnosing current infection in the present study were 78% and 98% respectively. The mean age of children with mycoplasma pneumoniae was higher than CAP with unspecified etiology. The presenting manifestations and initial laboratory finding were insufficient to predict mycoplasma pneumoniae precisely, the presence of chest pain and lobar consolidation on chest X-ray, however, were significant findings in children with mycoplasma pneumoniae. CONCLUSION: The present study confirms that M. pneumoniae plays a significant role in CAP in children of all ages. Children with this infection should be identified in order to administer the appropriate antibiotic treatment.

Human disease from influenza A (H5N1), Thailand, 2004.

Influenza A (H5N1) is endemic in poultry across much of Southeast Asia, but limited information exists on the distinctive features of the few human cases. In Thailand, we instituted nationwide surveillance and tested respiratory specimens by polymerase chain reaction and viral isolation. From January 1 to March 31, 2004, we reviewed 610 reports and identified 12 confirmed and 21 suspected cases. All 12 confirmed case-patients resided in villages that experienced abnormal chicken deaths, 9 lived in households whose backyard chickens died, and 8 reported direct contact with dead chickens. Seven were children <14 years of age. Fever preceded dyspnea by a median of 5 days, and lymphopenia significantly predicted acute respiratory distress syndrome development and death. Among hundreds of thousands of potential human cases of influenza A (H5N1) in Asia, a history of direct contact with sick poultry, young age, pneumonia and lymphopenia, and progression to acute respiratory distress syndrome should prompt specific laboratory testing for H5 influenza.

Medication errors at Queen Sirikit National Institute of Child Health.

BACKGROUND: In the past two years, medication errors have been recognized as having been unacceptably high among hospitalized patients. OBJECTIVE: To determine the incidence and type of medication errors, severity of events, patient outcomes and categories of drugs involved in the largest pediatric hospital in Thailand over a fifteen-month-period. PATIENTS AND METHOD: Retrospective review of in-patient medication errors documented in standard reporting forms from September 2001 to November 2002. Main outcome measure was the incidence of errors reported. RESULTS: Medication errors occurred in 1 per cent of admissions (322 errors of 32,105 admissions). The most common error type was prescription error (35.40%). The majority of errors were detected and prevented before the drugs were administered (76.71%). There was only one case of permanent brain damage; no deaths occurred in the study period. The most common group of drugs involved in medication errors was antibiotics and the most common route of administration was oral. CONCLUSION: Medication errors are not uncommon. There is a need to change the behaviors of recognizing and acknowledging clinical errors, including drug errors. Careful review of errors highlights the many opportunities to change how drug errors are addressed and to make them less likely.

Factors effecting the outcome of acute respiratory distress syndrome in pediatric patients treated with high frequency oscillatory ventilation.

OBJECTIVES: To evaluate the survival rate and factors affecting the outcome of pediatric patients treated with high-frequency oscillatory ventilation (HFOV) for diffuse alveolar disease (DAD) compatible with acute respiratory distress syndrome (ARDS). METHOD: A cohort study was conducted at the pediatric intensive care unit of Queen Siritkit National Institute of Child Health from 1st January 1999 to 31st December 2001. Children who suffered from DAD compatible with ARDS were enrolled. Inclusion criteria were PaO2/FiO2 < 200 and oxygenation index (OI) > 10. High-frequency oscillatory ventilator (3100A Sensor Medics Corp, Yorba Linda, Calif) was used applying high volume strategy of treatment. Patients were weaned to conventional ventilation (CV) once clinical improvement occurred. Demographic data, duration of CV mode before changing to HFOV, duration of HFOV, ventilator parameters and gas exchange variables from beginning and during the course of HFOV were recorded, so patient data could be compared between surviving and non-surviving groups. RESULTS: A total of 21 children were enrolled during the 3 year period. There were 4 patients with simultaneous air leak syndrome and a total of 10 male patients. The average age was 3.58 +/- 3.9 years. There were 11 surviving patients (52.4%). Data of ventilator parameters and gas exchange variables after changing to HFOV for 4-6 hours for the two groups, FiO2 was higher (0.99 +/- 0.32 vs 0.84 +/- 0.18; p = 0.02) and alveolar arterial oxygen gradient [P(A-a)O2] was lower (448.5 +/- 140.8 vs 562.7 +/- 99.9 mmHg; p = 0.047) in the surviving group than in the non-surviving group. Concerning mean airway pressure (Paw), oxygenation index (OI), P(A-a)O2 and PaO2/FiO2 at initiation and during the course of HFOV with comparison of the surviving and non-surviving groups: Paw and OI decreased in the surviving group and was significantly different at 36 and 24 hours respectively. P(A-a)O2 was statistically significantly lower at 6 hours after HFOV initiation in the surviving group. PaO2/FiO2 was statistically significantly increased at 24 hours in the surviving group. CONCLUSION: Implement of HFOV is useful in patients with DAD, ARDS and air leak syndrome from the initial phase of illness which fulfill criteria for decreasing ventilator induced lung injury and thus decrease the mortality rate from ARDS. Predisposing survival factor showing statistically significant differences was lower Paw during CV before changing to HFOV, lower Paw at 36 hours, lower OI at 24 hours, lower P(A-a)O2 at 6 hours and higher PaO2/FiO2 at 24 hours. These parameters are good indicators for the prognosis of ARDS for patients responding or not responding to HFOV.