Optimizing pediatric periprocedural pain management part II-Adjunct therapies to support the use of infiltrative anesthetics.

Pediatric procedure-related pain management is often incompletely understood, inadequately addressed, and critical in influencing a child's lifelong relationship with the larger healthcare community. We present a comprehensive review of infiltrative anesthetics, including a comparison of their mechanisms of action and relative safety and efficacy data to help guide clinical selection. We also describe the multimodal utilization of adjunct therapies-in series and in parallel-to support the optimization of pediatric periprocedural pain management, enhance the patient experience, and provide alternatives to sedation medication and general anesthesia.

Optimizing pediatric periprocedural pain management part I-Evolving ethics and topical anesthetics.

Pediatric procedure-related pain management is often incompletely understood, inadequately addressed, and critical in influencing a child's lifelong relationship with the larger health care community. We highlight the evolution of ethics and expectations around optimizing periprocedural pain management as a fundamental human right. We investigate the state-of-the-art of topical anesthetics, reviewing their mechanisms of action and providing comparisons of their relative safety and efficacy data to help guide clinical selection. In total, this two-part review offers a combination of conventional approaches and innovative techniques that should be used multimodally-in series and in parallel-to help optimize pain management and provide alternatives to sedation medication and general anesthesia.

Transfusion targets and adverse events in pediatric perioperative acute Anemia.

STUDY OBJECTIVE: To evaluate the association between pretransfusion and posttransfusion hemoglobin concentrations and the outcomes of children undergoing noncardiac surgery. DESIGN: Retrospective review of patient records. We focused on initial postoperative hemoglobin concentrations, which may provide a more useful representation of transfusion adequacy than pretransfusion hemoglobin triggers (the latter often cannot be obtained during acute surgical hemorrhage). SETTING: Single-center, observational cohort study. PATIENTS: We evaluated all pediatric patients undergoing noncardiac surgery who received intraoperative red blood cell transfusions from January 1, 2008, through December 31, 2018. INTERVENTIONS: None. MEASUREMENTS: Associations between pre- and posttransfusion hemoglobin concentrations (g/dL), hospital-free days, intensive care unit admission, postoperative mechanical ventilation, and infectious complications were evaluated with multivariable regression modeling. MAIN RESULTS: In total, 113,713 unique noncardiac surgical procedures in pediatric patients were evaluated, and 741 procedures met inclusion criteria (median [range] age, 7 [1-14] years). Four hundred ninety-eight patients (68%) with a known preoperative hemoglobin level had anemia; of these, 14% had a preexisting diagnosis of anemia in their health record. Median (IQR) pretransfusion hemoglobin concentration was 8.1 (7.4-9.2) g/dL and median (IQR) initial postoperative hemoglobin concentration was 10.4 (9.3-11.6) g/dL. Each decrease of 1 g/dL in the initial postoperative hemoglobin concentration was associated with increased odds of transfusion within the first 24 postoperative hours (odds ratio [95% CI], 1.62 [1.37-1.93]; P < .001). No significant relationships were observed between postoperative hemoglobin concentrations and hospital-free days (P = .56), intensive care unit admission (P = .71), postoperative mechanical ventilation (P = .63), or infectious complications (P = .74). CONCLUSIONS: In transfused patients, there was no association between postoperative hemoglobin values and clinical outcomes, except the need for subsequent transfusion. Most transfused patients presented to the operating room with anemia, which suggests a potential opportunity for perioperative optimization of health before surgery.

Survival-to-Hospital Discharge in Neonates With Congenital Heart Disease Supported With Prolonged Extracorporeal Membrane Oxygenation.

Factors that determine early outcomes in neonates with congenital heart disease (CHD) supported with prolonged venoarterial extracorporeal membrane oxygenation (ECMO) are not known and contemporary multicenter data are limited. This Extracorporeal Life Support Organization registry-based retrospective cohort study included all neonates (age ≤28 days) with CHD supported with venoarterial ECMO >7 days at 111 centers in the United States from January 2011 to December 2020. The primary outcome was survival-to-hospital discharge, and the secondary outcome was ECMO survival (successful decannulation before hospital discharge or death). Of the 2,155 total ECMO runs, 948 neonates received prolonged ECMO (gestational age [mean ± SD] 37.9 ± 1.8 weeks; birth weight 3.1 ± 0.6 kg; ECMO duration 13.6 ± 11.2 days). The ECMO survival rate was 51.6% (489 of 948), and the survival-to-hospital discharge rate was 23.9% (226 of 948). Body weight at ECMO (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.44 to 0.78/kg), gestational age (OR 0.89, 95% CI 0.79 to 1.00 per week), risk-adjusted congenital heart surgery-1 score (OR 1.22, 95% CI 1.04 to 1.45), and pump flow at 24 hours (OR 1.11, 95% CI 1.04 to 1.18 per 10 ml/kg/min) were significantly associated with survival-to-hospital discharge. Pre-ECMO mechanical ventilation duration, time to extubation after ECMO decannulation, and length of stay were inversely associated with hospital survival. Patient-specific (higher body weight and gestational age) and CHD-related (lower risk-adjusted congenital heart surgery-1 score) attributes are associated with better outcomes in neonates who receive prolonged venoarterial ECMO. Further elucidation of the factors associated with reduced survival to discharge in ECMO survivors is needed.

Activated Prothrombin Complex Concentrate in Pediatric Cardiac Patients, Our Early Experience.

BACKGROUND: Pediatric cardiac surgery is associated with abnormal coagulation, bleeding, and nearly ubiquitous transfusions. With the popularization of patient blood management, attempts are being made to decrease liberal transfusions by administering prothrombin complex concentrates (PCCs). The safety and efficacy of PCCs in adult cardiac surgery has been studied extensively, but only few reports address this in children. We performed an observational study focused on transfusion requirements after off-label use of activated PCC Factor Eight Inhibitor Bypassing Activity (FEIBA) as an adjunct to post-cardiopulmonary bypass (CPB) hemostatic protocol. METHODS: We reviewed the medical records of children ≤15 kg undergoing cardiac operations with CPB between May 2018 and March 2022. A propensity score (PS) analysis was performed to identify matched pairs of patients who did and did not receive FEIBA. RESULTS: Out of 210 patients who met the inclusion criteria, 44 patients received FEIBA. Propensity score-based analysis identified 40 matched pairs of patients with similar baseline characteristics. There was no statistically significant difference in the primary outcome-the volume of transfusion after CPB, which included all allogeneic blood products and salvaged washed red cells administered after protamine. Specifically, FEIBA patients were transfused 28 (22-34) mL/kg and controls were transfused 22 (11-49) mL/kg, P = .989. Upon arrival to ICU, the FEIBA group averaged an 8% lower international normalized ratio, compared with the controls (P = .009) and a 1.08 g/dL higher hemoglobin (P = .050). Neither difference remained significant on POD 1. CONCLUSIONS: In this exploratory study, we found no change in transfusion requirements after CPB despite FEIBA administration.

Effects of on-table extubation on resource utilization and maternal anxiety in children undergoing congenital heart surgery in a low-resource environment.

Objective: To study the applicability of on-table extubation (OTE) protocol following congenital cardiac surgery in a low-resource setting and its impact on the length of intensive care unit (ICU) stay, hospital stay, hospitalization cost, parental anxiety, and nurse anxiety. Materials and Methods: In this prospective, nonrandomized, observational single-center study, we included all children above 1 year of age undergoing congenital cardiac surgery. We evaluated them for the feasibility of OTE using a prespecified protocol following separation from cardiopulmonary bypass. The data were prospectively collected on 60 children more than 1 year of age, belonging to the Risk Adjustment for Congenital Heart Surgery 1, 2, 3, and 4 groups and divided into two groups: those who underwent successful OTE and those who were ventilated for any duration postoperatively (30 children in each group). Duration of hospital stay, ICU stay, and total hospital cost were collected. Anxiety levels of the primary caregiver (nurse) in the ICU and the mother were assessed immediately after the arrival of the child in the ICU using the State Trait Anxiety Inventory (STAI). Results: Children who were extubated immediately following congenital cardiac surgery had significantly shorter ICU stay (median 20 [19, 22] h vs. 22 [20, 43] h [P < 0.05]). Patients extubated on table had a significant reduction in hospital cost {median Rs. 161,000 (138,330; 211,900), approximately USD 1970 (P < 0.05)} when compared to children who were ventilated postoperatively {median Rs. 201,422 (151,211; 211,900) , approximately USD 2464}. The anxiety level in mothers was significantly less when their child was extubated in the operating room (STAI 36.5 ± 5.4 vs. 47.4 ± 7.4, P < 0.001). However, for the same subset of patients, anxiety level was significantly higher in the ICU nurse (STAI 46.0 ± 5.6 vs. 37.8 ± 4.1, P < 0.05). Conclusion: OTE following congenital cardiac surgery is associated with a shorter duration of ICU stay and hospital stay. It also reduces the total hospital cost and the anxiety level in mothers of children undergoing congenital heart surgery. However, the primary bedside caregiver during the child's ICU stay had increased anxiety managing patients with OTE.

Major Short-term Complications of Arterial Cannulation for Monitoring in Children.

BACKGROUND: Perioperative arterial cannulation in children is routinely performed. Based on clinical observation of several complications related to femoral arterial lines, the authors performed a larger study to further examine complications. The authors aimed to (1) describe the use patterns and incidence of major short-term complications associated with arterial cannulation for perioperative monitoring in children, and (2) describe the rates of major complications by anatomical site and age category of the patient. METHODS: The authors examined a retrospective cohort of pediatric patients (age less than 18 yr) undergoing surgical procedures at a single academic medical center from January 1, 2006 to August 15, 2016. Institutional databases containing anesthetic care, arterial cannulation, and postoperative complications information were queried to identify vascular, neurologic, and infectious short term complications within 30 days of arterial cannulation. RESULTS: There were 5,142 arterial cannulations performed in 4,178 patients. The most common sites for arterial cannulation were the radial (N = 3,395 [66.0%]) and femoral arteries (N = 1,528 [29.7%]). There were 11 major complications: 8 vascular and 3 infections (overall incidence, 0.2%; rate, 2 per 1,000 lines; 95% CI, 1 to 4) and all of these complications were associated with femoral arterial lines in children younger than 5 yr old (0.7%; rate, 7 per 1,000 lines; 95% CI, 4 to 13). The majority of femoral lines were placed for cardiac procedures (91%). Infants and neonates had the greatest complication rates (16 and 11 per 1,000 lines, respectively; 95% CI, 7 to 34 and 3 to 39, respectively). CONCLUSIONS: The overall major complication rate of arterial cannulation for monitoring purposes in children is low (0.2%). All complications occurred in femoral arterial lines in children younger than 5 yr of age, with the greatest complication rates in infants and neonates. There were no complications in distal arterial cannulation sites, including more than 3,000 radial cannulations.

Inability to Mask Ventilate During Myringotomy Tube Replacement: A Case Report.

We present the case of a 3-year-old female with multiple congenital anomalies, including postprandial otorrhea, who developed the inability to be mask ventilated secondary to a combination of velopharyngeal insufficiency and tympanic membrane perforation. When applied by mask, positive pressure ventilation was observed to preferentially escape the patient's left ear, resulting in significant air leak, insufficient tidal volumes, hypoventilation, and severe hypoxemia. The problem was remedied by the insertion of a finger into the patient's external auditory meatus, which controlled the air leak until the surgical team could provide definitive surgical correction of the velopharyngeal insufficiency and nasopharyngeal reflux.

Innovative 2-Step Management Strategy Utilizing EXIT Procedure for a Fetus With Hypoplastic Left Heart Syndrome and Intact Atrial Septum.

Hypoplastic left heart syndrome (HLHS) with intact atrial septum (HLHS-IAS) carries a high risk of mortality and affects about 6% of all patients with HLHS. Fetal interventions, postnatal transcatheter interventions, and postnatal surgical resection have all been used, but the mortality risk continues to be high in this subgroup of patients. We describe a novel, sequential approach to manage HLHS-IAS and progressive fetal hydrops. A 28-year-old, gravida 4 para 2 mother was referred to Mayo Clinic for fetal HLHS. Fetal echocardiography at 28 weeks of gestation demonstrated HLHS-IAS with progressive fetal hydrops. The atrial septum was thick and muscular with no interatrial communication. Ultrasound-guided fetal atrial septostomy was performed with successful creation of a small atrial communication. However, fetal echocardiogram at 33 weeks of gestation showed recurrence of a pleural effusion and restriction of the atrial septum. We proceeded with an Ex uteroIntrapartum Treatment (EXIT) delivery and open atrial septectomy. This was performed successfully, and the infant was stabilized in the intensive care unit. The infant required venoarterial extracorporeal membrane oxygenator support on day of life 1. The patient later developed hemorrhagic complications, leading to his demise on day of life 9. This is the first reported case of an EXIT procedure and open atrial septectomy performed without cardiopulmonary bypass for an open-heart operation and provides a promising alternative strategy for the management of HLHS-IAS in select cases.

Incidence and Epidemiology of Perioperative Transfusion-Related Pulmonary Complications in Pediatric Noncardiac Surgical Patients: A Single-Center, 5-Year Experience.

BACKGROUND: Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are the leading causes of transfusion-related fatalities. While these transfusion-related pulmonary complications (TRPCs) have been well detailed in adults, their burden in pediatric subsets remains poorly defined. We sought to delineate the incidence and epidemiology of pediatric TRPCs after intraoperative blood product transfusion. METHODS: In this retrospective cohort study, we evaluated all consecutive pediatric patients receiving intraoperative blood product transfusions during noncardiac surgeries between January 2010 and December 2014. Exclusion criteria were cyanotic heart disease, preoperative respiratory insufficiency, extracorporeal membrane oxygenation, and American Society of Anesthesiologists physical status VI. Medical records were electronically screened to identify those with evidence of hypoxemia, and in whom a chest x-ray was obtained within 24 hours of surgery. Records were then manually reviewed by 2 physicians to determine whether they met diagnostic criteria for TACO or TRALI. Disagreements were adjudicated by a third senior physician. RESULTS: Of 19,288 unique pediatric surgical patients, 411 were eligible for inclusion. The incidence of TRPCs was 3.6% (95% confidence interval [CI], 2.2-5.9). TACO occurred in 3.4% (95% CI, 2.0-5.6) of patients, TRALI was identified in 1.2% (95% CI, 0.5-2.8), and 1.0% (95% CI, 0.4-2.5) had evidence for both TRALI and TACO. Incidence was not different between males (3.4%) and females (3.8%; P = .815). Although a trend toward an increased incidence of TRPCs was observed in younger patients, this did not reach statistical significance (P = .109). Incidence was comparable across subsets of transfusion volume (P = .184) and surgical specialties (P = .088). Among the 15 patients experiencing TRPCs, red blood cells were administered to 13 subjects, plasma to 3, platelets to 3, cryoprecipitate to 2, and autologous blood to 3. Three patients with TRCPs were transfused mixed blood components. CONCLUSIONS: TRPCs occurred in 3.6% of transfused pediatric surgical patients, with the majority of cases attributable to TACO, congruent with adult literature. The frequency of TRPCs was comparable between genders and across surgical procedures and transfusion volumes. The observed trend toward increased TRPCs in younger children warrants further consideration in future investigations. Red blood cell administration was the associated component for the majority of TRPCs, although platelets demonstrated the highest risk per component transfused. Mitigation of perioperative risk associated with TRPCs in pediatric patients is reliant on further multiinstitutional studies powered to examine patterns and predictors of this highly morbid entity.

PROPER: Development of an Early Pediatric Intensive Care Unit Readmission Risk Prediction Tool.

OBJECTIVE: No risk prediction model is currently available to measure patient's probability for readmission to the pediatric intensive care unit (PICU). This retrospective case-control study was designed to assess the applicability of an adult risk prediction score (Stability and Workload Index for Transfer [SWIFT]) and to create a pediatric version (PRediction Of PICU Early Readmissions [PROPER]). DESIGN: Eighty-six unplanned early (<48 hours) PICU readmissions from January 07, 2007, to June 30, 2014, were compared with 170 random controls. Patient- and disease-specific data and PICU workload factors were compared across the 2 groups. Factors statistically significant on multivariate analysis were included in the creation of the risk prediction model. The SWIFT scores were calculated for cases and controls and compared for validation. RESULTS: Readmitted patients were younger, weighed less, and were more likely to be admitted from the emergency department. There were no differences in gender, race, or admission Pediatric Index of Mortality scores. A higher proportion of patients in the readmission group had a Pediatric Cerebral Performance Category in the moderate to severe disability category. Cases and controls did not differ with respect to staff workload at discharge or discharge day of the week; there was a much higher proportion of patients on supplemental oxygen in the readmission group. Only 2 of 5 categories in the SWIFT model were significantly different, and although the median SWIFT score was significantly higher in the readmissions group, the model discriminated poorly between cases and controls (area under the curve: 0.613). A 7-category PROPER score was created based on a multiple logistic regression model. Sensitivity of this model (score ≥12) for the detection of readmission was 81% with a positive predictive value of 0.50. CONCLUSION: We have created a preliminary model for predicting patients at risk of early readmissions to the PICU from the hospital floor. The SWIFT score is not applicable for predicting the risk for pediatric population.

Anesthetic-Related Neurotoxicity and Neuroimaging in Children: A Call for Conversation.

Each year millions of young children undergo procedures requiring sedation or general anesthesia. An increasing proportion of the anesthetics used are provided to optimize diagnostic imaging studies such as magnetic resonance imaging. Concern regarding the neurotoxicity of sedatives and anesthetics has prompted the US Food and Drug Administration to change labeling of anesthetics and sedative agents warning against repeated or prolonged exposure in young children. This review aims to summarize the risk of anesthesia in children with an emphasis on anesthetic-related neurotoxicity, acknowledge the value of pediatric neuroimaging, and address this call for conversation.

Propylene Glycol Toxicity in Adolescent with Refractory Myoclonic Status Epilepticus.

Propylene glycol (PG) is a solvent commonly used in medications that, while benign at low doses, may cause toxicity in adults and children at high doses. We describe a case and the physiologic sequelae of propylene glycol toxicity manifested in a critically ill adolescent male with refractory myoclonic status epilepticus aggressively treated with multiple PG-containing medications (lorazepam, phenobarbital, and pentobarbital)-all within accepted dosing guidelines and a total daily PG exposure previously recognized to be safe. Hemodynamic measurements by bedside echocardiography during clinical toxicity are also reported. Clinicians should have a high index of suspicion for propylene glycol toxicity in patients treated with PG-containing medications even when the total PG exposure is lower than currently accepted limits.

Anesthetic Outcomes of Children With Arthrogryposis Syndromes: No Evidence of Hyperthermia.

BACKGROUND: Arthrogryposis syndromes are a heterogeneous group of disorders characterized by congenital joint contractures often requiring multiple surgeries during childhood to address skeletal and visceral abnormalities. Previous reports suggest that these children have increased perioperative risk, including hypermetabolic events discrete from malignant hyperthermia, difficult airway management, isolated hyperthermia, and difficult IV line placement. We sought to compare children with arthrogryposis multiplex congenita (AMC) versus the less severe, distal arthrogryposis syndromes (DAS) and to evaluate possible intraoperative hyperthermia of patients with AMC. We hypothesized that children with AMC had a greater incidence of intraoperative hyperthermia and more difficulty with airway management and IV access. METHODS: Children aged 0 to 25 years with arthrogryposis syndromes who underwent anesthesia from 1972 to 2013 were identified. The medical records were reviewed for demographics, arthrogryposis type, and anesthetic complications. AMC subjects were compared with DAS subjects. To evaluate the probability of hyperthermia and hypermetabolic responses of patients with AMC, we performed a post hoc case-control analysis. Patients with AMC were matched in a 1:2 ratio to patients without arthrogryposis to evaluate the primary outcome of maximum intraoperative temperature. RESULTS: Forty-five patients with AMC and 16 patients with DAS underwent 264 and 105 unique anesthetics, respectively. There was no significant difference in intraoperative hyperthermia or hypermetabolic events (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.36-2.47; P = .90). Children with AMC were more likely to have difficult IV access (OR, 7.1; 95% CI, 1.81-27.90; P = .005). Additional evidence suggested that difficult airway management (OR, 4.06; 95% CI, 1.01-16.39; P = .049) and hemodynamic instability (OR, 4.22; 95% CI, 1.03-17.26; P = .045) were more likely in children with AMC. From post hoc case-control analysis, there was no significant difference in the mean maximum intraoperative temperature (estimated difference +0.04°C; 95% CI, -0.14 to +0.22; P = .64) or odds of intraoperative hyperthermia (OR, 1.49; 95% CI, 0.78-2.82; P = .223) for patients with AMC compared with control subjects. CONCLUSIONS: Children with arthrogryposis syndromes present challenges to the anesthesia and surgical teams, including greater neuromuscular disease burden and challenging peripheral IV placement, with additional evidence suggesting difficult airway management and intraoperative hemodynamic instability. Although more definitive studies are warranted, we did not find evidence of increased odds of intraoperative hyperthermia or hypermetabolic responses.

Improvement in Patient Transfer Process From the Operating Room to the PICU Using a Lean and Six Sigma-Based Quality Improvement Project.

BACKGROUND AND OBJECTIVES: Ineffective and inefficient patient transfer processes can increase the chance of medical errors. Improvements in such processes are high-priority local institutional and national patient safety goals. At our institution, nonintubated postoperative pediatric patients are first admitted to the postanesthesia care unit before transfer to the PICU. This quality improvement project was designed to improve the patient transfer process from the operating room (OR) to the PICU. METHODS: After direct observation of the baseline process, we introduced a structured, direct OR-PICU transfer process for orthopedic spinal fusion patients. We performed value stream mapping of the process to determine error-prone and inefficient areas. We evaluated primary outcome measures of handoff error reduction and the overall efficiency of patient transfer process time. Staff satisfaction was evaluated as a counterbalance measure. RESULTS: With the introduction of the new direct OR-PICU patient transfer process, the handoff communication error rate improved from 1.9 to 0.3 errors per patient handoff (P = .002). Inefficiency (patient wait time and non-value-creating activity) was reduced from 90 to 32 minutes. Handoff content was improved with fewer information omissions (P < .001). Staff satisfaction significantly improved among nearly all PICU providers. CONCLUSIONS: By using quality improvement methodology to design and implement a new direct OR-PICU transfer process with a structured multidisciplinary verbal handoff, we achieved sustained improvements in patient safety and efficiency. Handoff communication was enhanced, with fewer errors and content omissions. The new process improved efficiency, with high staff satisfaction.

Comparison of staff and family perceptions of causes of noise pollution in the Pediatric Intensive Care Unit and suggested intervention strategies.

Noise and excessive, unwanted sound in the Pediatric Intensive Care Unit (PICU) is common and has a major impact on patients' sleep and recovery. Previous research has focused mostly on absolute noise levels or included only staff as respondents to acknowledge the causes of noise and to plan for its reduction. Thus far, the suggested interventions have not ameliorated noise, and it continues to serve as a barrier to recovery. In addition to surveying PICU providers through internet-based software, patients' families were evaluated through in-person interviews utilizing a pretested instrument over 3 months. Families of patients admitted for more than 24 h were considered eligible for evaluation. Participants were asked to rank causes of noise from 1 to 8, with eight being highest, and identified potential interventions as effective or ineffective. In total, 50 families from 251 admissions and 65 staff completed the survey. Medical alarms were rated highest (mean ± standard deviation [SD], 4.9 ± 2.1 [2.8-7.0]), followed by noise from medical equipment (mean ± SD, 4.7 ± 2.1 [2.5-6.8]). This response was consistent among PICU providers and families. Suggested interventions to reduce noise included keeping a patient's room door closed, considered effective by 93% of respondents (98% of staff; 88% of families), and designated quiet times, considered effective by 82% (80% of staff; 84% of families). Keeping the patient's door closed was the most effective strategy among survey respondents. Most families and staff considered medical alarms an important contributor to noise level. Because decreasing the volume of alarms such that it cannot be heard is inappropriate, alternative strategies to alert staff of changes in vital signs should be explored.

Pediatric bicycle-related head injuries: a population-based study in a county without a helmet law.

BACKGROUND: Head injuries are the leading cause of death among cyclists, 85 % of which can be prevented by wearing a bicycle helmet. This study aims to estimate the incidence of pediatric bicycle-related injuries in Olmsted County and assess differences in injuries between those wearing helmets vs. not. METHODS: Olmsted County, Minnesota residents 5 to 18 years of age with a diagnostic code consistent with an injury associated with the use of a bicycle between January 1, 2002, and December 31, 2011, were identified. Incidence rates were calculated and standardized to the age and sex distribution of the 2000 US white population. Type of injuries, the percentage requiring head CT or X-ray, and hospitalization were compared using a chi-square test. Pediatric intensive care unit (PICU) admission, permanent neurologic injury, seizure, need for mechanical ventilation, and mortality were compared using Fisher's exact test. RESULTS: A total of 1189 bicycle injuries were identified. The overall age-adjusted incidence rate of all injuries was 278 (95 % CI, 249 to 306) per 100,000 person-years for females and 589 (95 % CI, 549 to 629) for males. The corresponding rates for head injuries were 104 (95 % CI, 87 to 121) for females and 255 (95 % CI, 229 to 281) for males. Of patients with head injuries, 17.4 % were documented to have been wearing a helmet, 44.8 % were documented as not wearing a helmet, and 37.8 % had no helmet use documentation. Patients with a head injury who were documented as not wearing a helmet were significantly more likely to undergo imaging of the head (32.1 percent vs. 11.5 %; p < 0.001) and to experience a brain injury (28.1 vs. 13.8 %; p = 0.008). CONCLUSIONS: Children and adolescents continue to ride bicycles without wearing helmets, resulting in severe head and facial injuries and mortality.

Effect of positive end-expiratory pressure on acoustic wave propagation in experimental porcine lung injury.

To evaluate the effect of positive end-expiratory pressure (PEEP) on sound propagation through injured lungs, we injected a multifrequency broad-band sound signal into the airway of eight anesthetized, intubated and mechanically ventilated pigs, while recording transmitted sound at three locations bilaterally on the chest wall. Oleic acid injections effected a severe pulmonary oedema predominately in the dependent lung regions, with an average increase in venous admixture from 19 ± 15 to 59 ± 14% (P < 0.001), and a reduction in dynamic respiratory system compliance from 34 ± 7 to 14 ± 4 ml cmH2 O(-1) (P < 0.001). A concomitant decrease in sound transit time was seen in the dependent lung regions (P < 0.05); no statistically significant change occurred in the lateral or non-dependent areas. The application of PEEP resulted in a decrease in venous admixture, increase in respiratory system compliance and return of the sound transit time to pre-injury levels in the dependent lung regions. Our results indicate that sound transmission velocity increases in lung tissue affected by permeability-type pulmonary oedema in a manner reversible during alveolar recruitment with PEEP.