All that glitters is not gold: Mercury poisoning in a family mimicking an infectious illness.

Three siblings with inhalational elemental mercury toxicity presented with fever, rash, and upper respiratory tract symptoms. The patients were heavily exposed to elemental mercury that was spilled in their home and then vacuumed. Initial whole blood mercury levels were elevated at >200 µg/L, 153 µg/L and 130 µg/L (Mayo Clinic Laboratories lab reference range <9 µg/L) for Cases 1, 2, and 3, respectively. All three required chelation with succimer. Clinically significant elemental mercury toxicity can resemble an infectious illness. Severe morbidity and mortality can be prevented if heavy metal poisoning is considered early, through a detailed history including an environmental exposure history. For elemental mercury spills in the home, safe and effective clean-up steps are needed. Improved public health education is needed to prevent similar household exposures.

Bag Valve Mask Ventilation as a Perceptual-Cognitive Skill.

Objective This study used a high-fidelity infant mannequin to examine the relationship between the quality of bag valve mask ventilation (BVMV) and how providers of varying levels of experience use visual feedback (e.g., electronic vital signs) to guide their performance. Background BVMV is a common and critical procedure for managing pediatric respiratory emergencies. However, providers do not consistently deliver effective BVMV. Efforts to improve BVMV have ignored the question of how providers effectively use feedback often available during BVMV. Method Six expert and six novice respiratory therapists completed two simulations of an infant requiring BVMV. In one, the technology failed to display SpO2, an important but somewhat redundant visual cue. Eye movements, verbal reports, and ventilation rate (in breaths per minute) were measured in each simulation. Results Regardless of SpO2 availability, eye movements and verbal reports suggested that novices depended strongly on electronic vital signs and when SpO2 was absent ventilated at a faster rate (exceeding the recommended range of ventilation rates) than when SpO2 was present. Experts' ventilation rates were comparable and within the recommended range in both conditions. When SpO2 was absent, experts emphasized information from direct observation of the patient that novices neglected. Conclusion Individual differences in the use of feedback during BVMV contribute to the quality of BVMV. This work bears on the theoretical discussions involving the use of automation and nontechnological cues to guide performance. Application These results have the potential to expand the current understanding of factors underlying effective BVMV with implications for training novice providers.

Spontaneous breathing trial predicts successful extubation in infants and children.

OBJECTIVE: To assess the value of a spontaneous breathing trial (SBT) using a flow-inflating bag in predicting extubation success. Secondary goals were to evaluate the positive and negative predictive accuracy of a 15-min SBT. DESIGN: Prospective, blinded, clinical study. SETTING: Pediatric intensive care unit (ICU) of a university hospital PATIENTS: Infants and children intubated for >or=24 hrs. INTERVENTIONS: Patients who met defined criteria for extubation underwent a 15-min SBT connected to a flow-inflating bag set to provide 5 cm H2O continuous positive airway pressure. MEASUREMENTS AND MAIN RESULTS: Seventy patients underwent the SBT. Respiratory rate, heart rate, blood pressure, and pulse oxygen saturations were recorded at baseline and at 5 and 15 mins into the SBT. The ICU physicians were blinded to the results of the SBT, and all patients were extubated at the end of the trial. Patients were observed for the next 24 hrs, and the need for noninvasive ventilation or reintubation (i.e., extubation failure) was recorded.Sixty-four patients (91%) passed the SBT with a subsequent extubation failure rate of 7.8% (only 1.6% required reintubation). Six of the 70 (9%) patients enrolled failed the trial, but half were extubated successfully. Successful completion of the SBT has a 95% sensitivity for predicting successful extubation with a positive predictive value of 92% and an odds ratio of 12 (95% confidence interval, 1.3, 53.7). The specificity of the SBT was 37% with a negative predictive value of 50%. Logistic regression analysis revealed a significant association between passing the SBT and extubation success (p = .017). CONCLUSIONS: A 15-min flow-inflating bag SBT represents a practical, reliable bedside test that has 95% sensitivity for predicting extubation success in pediatric ICU patients. A trial failure is associated with but does not accurately predict extubation failure.

Intratracheal pressure: a more accurate reflection of pulmonary airway pressure in pediatric patients with respiratory failure.

OBJECTIVES: Peak inflation pressure (PIP) on many ventilators (P(vent)), measured distal to the exhalation limb or Y-piece of the breathing circuit, is assumed as the pressure applied to the airways and lungs. However, in vitro studies show P(vent) data are spurious. There are no studies evaluating the accuracy of P(vent) data for pediatric patients with acute respiratory failure. We hypothesized that intratracheal airway pressure (P(T)) is more accurate than P(vent) and that by using P(vent), abnormally increased imposed resistive work of breathing (WOBi) may go undetected. DESIGN: Prospective and descriptive study. SETTING: A pediatric intensive care unit at a university hospital. PATIENTS: Twenty-one pediatric patients with respiratory failure requiring mechanical ventilation. INTERVENTIONS: All patients were intubated with a commercially available endotracheal tube (ETT) with a pressure measuring the lumen opening at the distal end used for measuring P(T). Pressure/flow sensors positioned between the ETT and Y-piece measured tidal volume (V(T)) and flow rate. P(vent) data were recorded as displayed on the ventilator. WOBi was measured by integrating P(T) and V(T) data. RESULTS: PIP at P(vent) and P(T) were 26 +/- 8 cm H(2)O and 19 +/- 7 cm H(2)O, respectively (p < .05). P(T) measurements averaged 27% less than P(vent). The relationship between P(vent)-P(T) (pressure drop across the breathing circuit and ETT) and flow rate during spontaneous inhalation was highly correlated (r = .80, p < .002), indicating the greater the flow rate, the greater the pressure drop and WOBi. WOBi, ranging from 0.04-1.5 J/L, was measured in 52% of the patients. CONCLUSIONS: P(vent) significantly overestimates PIP. Moreover, P(vent) data does not allow for recognition of increased WOBi for many patients. Clinicians need to be aware of the limitations of P(vent) data and consider using ETTs that allow measurement of P(T), a more accurate reflection of pulmonary airway pressure.