Adverse Heart-Lung Interactions in Ventilator-induced Lung Injury.

RATIONALE: In the original 1974 in vivo study of ventilator-induced lung injury, Webb and Tierney reported that high Vt with zero positive end-expiratory pressure caused overwhelming lung injury, subsequently shown by others to be due to lung shear stress. OBJECTIVES: To reproduce the lung injury and edema examined in the Webb and Tierney study and to investigate the underlying mechanism thereof. METHODS: Sprague-Dawley rats weighing approximately 400 g received mechanical ventilation for 60 minutes according to the protocol of Webb and Tierney (airway pressures of 14/0, 30/0, 45/10, 45/0 cm H2O). Additional series of experiments (20 min in duration to ensure all animals survived) were studied to assess permeability (n = 4 per group), echocardiography (n = 4 per group), and right and left ventricular pressure (n = 5 and n = 4 per group, respectively). MEASUREMENTS AND MAIN RESULTS: The original Webb and Tierney results were replicated in terms of lung/body weight ratio (45/0 > 45/10 ≈ 30/0 ≈ 14/0; P < 0.05) and histology. In 45/0, pulmonary edema was overt and rapid, with survival less than 30 minutes. In 45/0 (but not 45/10), there was an increase in microvascular permeability, cyclical abolition of preload, and progressive dilation of the right ventricle. Although left ventricular end-diastolic pressure decreased in 45/10, it increased in 45/0. CONCLUSIONS: In a classic model of ventilator-induced lung injury, high peak pressure (and zero positive end-expiratory pressure) causes respiratory swings (obliteration during inspiration) in right ventricular filling and pulmonary perfusion, ultimately resulting in right ventricular failure and dilation. Pulmonary edema was due to increased permeability, which was augmented by a modest (approximately 40%) increase in hydrostatic pressure. The lung injury and acute cor pulmonale is likely due to pulmonary microvascular injury, the mechanism of which is uncertain, but which may be due to cyclic interruption and exaggeration of pulmonary blood flow.

Early critical care course in children after liver transplant.

Objective. To review the critical care course of children receiving orthotopic liver transplantation (OLT). Methods. A retrospective chart review of patients admitted to the pediatric critical care following OLT performed in our center between 1988 and 2011. Results. A total of 149 transplants in 145 patients with a median age of 2.7 (IQR 0.9-7) years were analyzed. Mortality in the first 28 days was 8%. The median length of stay (LOS) was 7 (4.0-12.0) days. The median length of mechanical ventilation (MV) was 3 (1.0-6.2) days. Open abdomen, age, and oxygenation index on the 2nd day predicted LOS. Open abdomen, age, amount of blood transfused during surgery, and PRISM III predicted length of MV. 28% of patients had infection and 24% developed acute rejection. In recent group (2000-2011) OLT was performed in younger patients; the risk of infection and acute rejection was reduced and patients required longer LOS and MV compared with old group (1988-1999). Conclusion. The postoperative course of children after OLT is associated with multiple complications. In recent years OLT was performed in younger children; living donors were more common; the rate of postoperative infection and suspected rejection was reduced significantly; however patients required longer MV and LOS in the PCCU.

Anemia among Pediatric Critical Care Survivors: Prevalence and Resolution.

To determine the incidence of anemia among pediatric critical care survivors and to determine whether it resolves within 6 months of discharge. Design. A prospective observational study. Patients with anemia upon discharge from the pediatric critical care unit (PCCU) underwent in hospital and post hospital discharge followup (4-6 months) for hemoglobin (Hb) levels. Setting. A medical-surgical PCCU in a tertiary care center. Patients. Patients aged 28 days to 18 years who were treated in the PCCU for over 24 hours. Measurements and Main Results. 94 (24%) out of 392 eligible patients were anemic at time of discharge. Patients with anemia were older, median 8.0 yrs [(IQR 1.0-14.4) versus 3.2 yrs (IQR 0.65-9.9) (P < 0.001)], and had higher PeLOD [median 11 (IQR 10-12) versus 1.5 (1-4) (P < 0.001)], and PRISM [median 5 (IQR 2-11) versus 3 (IQR 0-6) (P < 0.001)] scores. The Hb level normalized in 32% of patients before discharge from hospital. Of the 28 patients who completed followup, all had normalization of their Hb in the absence of medical intervention. Conclusions. Anemia is not common among patients discharged from the PCCU and recovers spontaneously within 4-6 months.

Coagulation assessment in children with diabetic ketoacidosis.

OBJECTIVES: To assess potential hypercoagulability during diabetic ketoacidosis in children. DESIGN: A prospective, controlled pilot study. SETTING: University-affiliated pediatric critical care unit and emergency department in a tertiary care children's hospital. PATIENTS: Children (1-18 years) admitted with an episode of diabetic ketoacidosis and healthy children as controls. All patients with diabetic ketoacidosis managed according to a preestablished protocol. INTERVENTIONS: Thromboelastography was performed using citrated whole-blood samples drawn at the time of admission and upon biochemical and clinical resolution of diabetic ketoacidosis. Citrated whole-blood samples drawn from healthy nondiabetic children acted as control samples. MEASUREMENTS AND MAIN RESULTS: Fifteen patients (11.7 ± 4.1 years) in the diabetic ketoacidosis group and 20 patients (8.9 ± 4.5 years; p = 0.06) in the control group completed the study. Values for standard thromboelastography parameters (R and K time, α angle, maximum amplitude, coagulation index, and Ly30) in the diabetic ketoacidosis group, both on admission and resolution, were within the control range; thromboelastography profiles of diabetic ketoacidosis patients on admission were not significantly different from profiles obtained upon diabetic ketoacidosis resolution. The mean α-angle was significantly higher in known diabetic patients compared with newly diagnosed diabetics on admission; however, it still remained within the control normal range. CONCLUSIONS: Thromboelastographic assay results do not reflect a hypercoagulable state in this group of children with diabetic ketoacidosis. Further investigation is required to examine the potential role of injured endothelium in the suspected hypercoagulability during diabetic ketoacidosis.

Resuscitation volume in paediatric non-haemorrhagic blunt trauma.

INTRODUCTION: Trauma is a major cause of paediatric morbidity and mortality, yet knowledge of fluid resuscitation is limited. Our objectives were to determine current practises in resuscitation volume (RV) administered to paediatric non-haemorrhagic (NH) blunt trauma patients and to identify fluid related complications. METHODS: We examined data from 139 trauma patients 1-17 years of age with an injury severity score ≥ 12 resuscitated at a Trauma-designated Children's Hospital. Patients were separated into discreet groups based on ATLS age-dependent vital functions: toddler/preschooler (1-5 years), school age (6-12 years) and adolescent (13-17 years). RESULTS: The median RV (total fluid intake-maintenance fluid intake) in ml/kg over the first 24h from the time of trauma by age was: 24 (IQR=19-47; 1-5 years); 26 (IQR=15-36; 6-12 years); and 22 (IQR=14-42; 13-17 years). The differences in RV/kg/24h following NH trauma was not significantly different between age groups (p=0.41). Urine output over the 24h ranged from 2.5 (IQR=1.9-3.3; lower age group) to 1.8 (IQR=1.2-2.4; upper age group) ml/kg/h; greater than the ATLS recommended age-dependent targets. Haematocrit was the only significant independent predictor of RV/kg/24h (p<0.001). Fluid-related complications attributable to RV were identified in 12% (n=17/139) of patients, and included ascites (8%; n=11/139) and/or pleural effusion(s) (9%; n=13/139). Patients with fluid-related complications received significantly more RV in ml/kg/24h (42, IQR=27-76) than those without complications (22, IQR=14-36; p=0.001). CONCLUSIONS: The range of median RV administered to paediatric NH blunt trauma patients with ISS ≥ 12 was 22-26 ml/kg/24h. The RV administered was excessive based on high urine outputs and the presence of fluid-related complications. Further evaluation of RV triggers and endpoints used by paediatric traumatologists is required.

Dehydration in children with diabetic ketoacidosis: a prospective study.

OBJECTIVES: To investigate the association between the degree of patient dehydration on presentation with diabetic ketoacidosis (DKA) and clinical and laboratory parameters obtained on admission. DESIGN: Prospective descriptive study. SETTING: A tertiary care children's hospital. PATIENTS: Thirty-nine paediatric patients (1 month-16 years) presenting with 42 episodes of DKA. INTERVENTION: Clinical and biochemical variables were collected on admission. Dehydration was calculated by measuring acute changes in body weight during the period of illness. All patients were treated according to a previously established protocol. MAIN OUTCOME MEASURES: Magnitude of dehydration, defined as % loss of body weight (LBW), was determined by the difference in body weight obtained at presentation and at discharge. The relationship between the magnitude of dehydration and the clinical assessment and biochemical parameters was examined. RESULTS: The median (25th-75th centiles) magnitude of dehydration at presentation was 5.7% (3.8-8.3%) (mean ± SD 6.8 ± 5%). Neither the initial clinical assessment nor the comprehensive biochemical profile at admission correlated with the magnitude of dehydration. Despite considerable variation in the degree of dehydration and biochemical disequilibrium, all patients recovered from DKA within 24 h with a standardised therapeutic approach. Furthermore, the rapidity of patient recovery did not correlate with the magnitude of dehydration on presentation or the amount of fluid administered (median (25th-75th centiles) 48.8 ml/kg (38.5-60.3)) in the first 12 h. CONCLUSION: The magnitude of dehydration in DKA is not reflected by either clinical or biochemical parameters. These findings need confirmation in larger studies.

Transient blindness as the primary symptom of acute hyponatremia post surgery.

Hyponatremia is a common electrolyte abnormality among children and adults. Visual disturbance associated with hyponatremia has been described in the past; however, all of these cases presented primarily with other classical signs and symptoms of hyponatremia, such as seizures, gastrointestinal upset, lethargy, or headache. We present a child who developed blindness on post-operative day #6 after resection of a brain tumour. Computed tomography of the head showed no new bleed, mass lesion, edema, or occipital lobe pathology. Laboratory evaluation revealed acute hyponatremia (115 mmol/L). No other obvious symptoms of hyponatremia were present prior to its identification. As her hyponatremia was gradually corrected, her blindness completely resolved. This is the first reported patient with acute hyponatremia to present primarily with blindness; a "precondition" of chronically increased intracranial pressure (first hit) compounded by acute hyponatremia (second hit) may have induced reversible visual loss. Checking electrolytes should be the standard of care for neurosurgical patients with acute visual disturbance or other unexplained symptoms. It is a simple measure that quickly identifies a dangerous but reversible condition.

Complications of mechanical ventilation in the pediatric population.

BACKGROUND: Mechanical ventilation (MV) strategies are continuously evolving in an effort to minimize adverse events. The objective of this study was to determine the complications associated with MV in children. STUDY DESIGN: Prospective observational study. Over a period of 10 consecutive months, 150 patients (median age 0.8 years, IQR 4.4, 59% male) were enrolled in this study. RESULTS: The median duration of MV was 3.1 days (IQR 3.9). A total of 85 complications were observed in 60 (40%) patients (114 complications per 1,000 ventilation days). 16.7% of patients developed atelectasis, 13.3% post-extubation stridor, 9.3% failed extubation, 2.0% pneumothorax, 3.3% accidental extubation, 2.7% nasal or perioral tissue damage and 1.9% ventilator associated pneumonia. Atelectasis occurred most often in the left lower lobe (36%) or in the right upper lobe (26%). The incidence of atelectasis in children <1 year of age was 12% (31 episodes per 1,000 days of ventilation) compared to 18% (57 episodes per 1,000 days of ventilation) in children ≥ 1 year of age (P < 0.05). Patients that failed extubation were ventilated for a median of 8.5 (IQR 8.8) days compared to 2.9 days (IQR, 3.8) in patients that were successfully extubated (P < 0.01). The absence of an air leak prior to extubation did not correlate with failed extubation. Accidental extubation was limited to orally intubated patients. CONCLUSION: MV complications occurred in 40% of patients and most often consisted of atelectasis and post-extubation stridor. Further studies are needed to examine associated risk factors and strategies to reduce their occurrence.

Positive end-expiratory pressure improves survival in a rodent model of cardiopulmonary resuscitation using high-dose epinephrine.

BACKGROUND: Multiple interventions have been tested in models of cardiopulmonary resuscitation (CPR) to optimize drug use, chest compressions, and ventilation. None has studied the effects of positive end-expiratory pressure (PEEP) on outcome. We hypothesized that because PEEP can reverse pulmonary atelectasis, lower pulmonary vascular resistance, and potentially improve cardiac output, its use during CPR would increase survival. METHODS: Anesthetized Sprague-Dawley rats were exposed to 1 min of asphyxial cardiac arrest. Resuscitation was standardized and consisted of chest compressions, oxygen (Fio(2) 1.0), and IV epinephrine 30 microg/kg (Series 1) and 10 microg/kg (Series 2). Left ventricular function was assessed by echocardiography (Series 1), and animals were randomized to receive either 5 cm H(2)O PEEP or zero PEEP at commencement of CPR and throughout resuscitation. Survival was defined as the presence of a spontaneous circulation 60 or 120 min (Series 2) after initial resuscitation. RESULTS: There were no baseline differences between the groups. In Series 1, administration of 5 cm H(2)O PEEP (Fio(2) 1.0 and 0.21) was associated with improved survival compared with zero PEEP (7/9 and 6/6 vs 0/9, P < 0.01 and <0.001, respectively). Application of 5 cm H(2)O PEEP (Fio(2) 1.0) increased left ventricular end-diastolic area, systemic oxygenation, and functional residual capacity. Use of PEEP during CPR did not adversely affect left ventricular systolic function or arterial blood pressure. The outcome differences were not due to increased oxygenation because the rank order of survival was 5 cm H(2)O PEEP (Fio(2) 1.0) approximately 5 cm H(2)O PEEP (Fio(2) 0.21) > zero PEEP (Fio(2) 1.0), whereas the rank order of Pao(2) was 5 cm H(2)O PEEP (Fio(2) 1.0) > 5 cm H(2)O PEEP (Fio(2) 0.21) approximately zero PEEP (Fio(2) 1.0). In an additional series in which epinephrine 10 microg/kg was used (Series 2), the survival was 100% with no beneficial effects of PEEP. CONCLUSION: In asphyxial cardiac arrest in a small rodent model, continuous application of PEEP (5 cm H(2)O) during and after CPR had beneficial effects on survival that were independent of oxygenation and without adverse cardiovascular effects.

Lung contusion in children--early computed tomography versus radiography.

OBJECTIVE: To investigate, in children, the correlation between the extent of lung contusion as detected on early radiologic examination (chest radiograph [CXR] and/or thoracic computed tomography [TCT]) and subsequent clinical outcome measures. DESIGN: Retrospective chart review study with blinded assessment of thoracic imaging. SETTING: A university-affiliated, level 1 designated pediatric trauma center. INTERVENTIONS: None. PATIENTS: Patients (1-18 yrs) who, between April 2000 and October 2005, were diagnosed with lung contusion were eligible for study entry. The medical records of those patients who underwent early (within the first 24 hrs of admission) thoracic imaging (CXR and/or TCT) were reviewed. A pulmonary contusion score (PCS) was assigned to each thoracic image according to the extent of contusion injury by two investigators blinded to each others score and the clinical details of the patient. RESULTS: Seventy-four patients were included in the study. Twenty patients had undergone CXR only, whereas 54 had undergone both CXR and TCT. The mean PCS on CXR was 3.9 +/- 3.6 compared with 6.5 +/- 3.49 on TCT (p < .001). In eight patients (15%) who underwent TCT and CXR, the CXR failed to demonstrate a lung contusion. The PCS derived from CXR examination correlated positively with lower Pao2/Fio2 (r = -.36, p = .019), higher ventilation index (r = .35, p = .014), and longer length of ventilation (r = .28, p = .019). No such correlation was seen with TCT-derived PCS. CONCLUSIONS: The severity of lung contusion determined by CXR, but not TCT, correlates with impairment of oxygenation, CO2 exchange, and duration of ventilatory support.

External ventricular drains in pediatric patients.

OBJECTIVE: To determine the indications and complications of external ventricular drain (EVD) placement in pediatric patients. DESIGN: Retrospective chart review. SETTING: University associated, tertiary-level Children's Hospital. PATIENTS: Sixty-six [median age, 10.1 years (interquartile range, 5.9)] patients between 1994 and 2006 with 96 EVDs. MEASUREMENTS AND RESULTS: Clinical indications for EVD insertion include traumatic brain injury (TBI; 36%), acute hydrocephalus (35%), and ventriculoperitoneal shunt failure (29%). Of the 96 EVDs, 65% were inserted at the bedside in the pediatric critical care unit (PCCU) and 33% in the operating room (OR). Median duration of EVD insertion was 7.0 days (interquartile range, 8.8). Complications occurred with 26% of EVD insertions and included infection (9.4%), misplacement (6.3%), hemorrhage (4.2%), obstruction (3.1%), and malfunction (3.1%). The primary infectious etiology was coagulase-negative Staphylococcus (67% of infections). Despite patients with TBI having significantly smaller lateral ventricles than hydrocephalus patients (p < 0.05), EVD complications were similar (risk ratios 1.41; 95% confidence interval 0.68-2.72). Furthermore, the complication rate was the same for EVDs inserted in either the PCCU or OR (risk ratios 1.10; 95% confidence interval 0.55-2.29). CONCLUSION: EVDs were placed for TBI, ventriculoperitoneal shunt failure and new-onset hydrocephalus. The overall complication rate was 26%. Complication rates were similar in TBI and hydrocephalus patients, and with EVDs inserted in either the PCCU or OR. Prophylactic antibiotics or antimicrobial-impregnated catheters directed against coagulase-negative Staphylococcus may reduce EVD infections.

Neonatal myocardial infarction secondary to umbilical venous catheterization: A case report and review of the literature.

Neonatal acute myocardial infarction (MI) is a rare event, with a high mortality rate. Early recognition and intensive care management can be successful, and it requires a high index of suspicion in cases of unknown cardiogenic shock. The lack of access to cardiac catheterization should not delay management. Furthermore, there is great potential for myocardial regeneration to occur in surviving neonates with MI, emphasizing the importance of early recognition and management. The present report describes a neonate with an anatomically normal heart and coronary arteries who developed clinical, laboratory and electrocardiographic features of MI, and was managed successfully with fluid resuscitation, inotropic drugs and vasodilators.

Vascular remodeling protects against ventilator-induced lung injury in the in vivo rat.

BACKGROUND: The role of the pulmonary vasculature in the pathogenesis of ventilator-induced lung injury is not well established. In this study, the authors investigated the effect of vascular remodeling due to chronic pulmonary hypertension on susceptibility to ventilator-induced lung injury. The authors hypothesized that the enhanced vascular tensile strength associated with pulmonary vascular remodeling would protect against ventilator-induced lung injury. METHODS: Chronic pulmonary arterial hypertension was induced in rats by exposure to hypoxia for 28 days and was confirmed by demonstration of right ventricular hypertrophy. Normotensive and hypertensive groups of rats (as well as a group in which pulmonary hypertension was acutely reversed with a Rho-kinase inhibitor, Y-27632) were exposed to injurious ventilation (respiratory rate 30 min, 30/0 cm H2O) for 90 min. Lung injury was assessed by change in lung mechanics, oxygenation, edema development, and cytokine levels. Electron microscopy was used to examine vascular structure in additional animals. RESULTS: Injurious ventilation caused significant lung injury (lung compliance, oxygenation, pulmonary edema) in the normotensive controls, but not in the presence of pulmonary hypertension; acute reversal of pulmonary hypertension did not alter the lessened susceptibility to ventilator-induced lung injury. Electron microscopy demonstrated capillary endothelial and epithelial breaks in injuriously ventilated normotensive controls that were not seen with pulmonary hypertension, whether or not the pulmonary hypertension was acutely reversed. CONCLUSIONS: Vascular remodeling induced by chronic pulmonary hypertension confers protection against the effects of injurious mechanical ventilation in vivo by a mechanism that may involve structural alterations rather than increased pulmonary artery pressure.

Elective tracheostomy in mechanically ventilated children in Canada.

OBJECTIVE: To determine the current practice and opinions of paediatric intensivists in Canada regarding tracheostomy in children with potentially reversible conditions which are anticipated to require prolonged mechanical ventilation. DESIGN AND SETTING: Self-administered survey among paediatric intensivists within paediatrics critical care units (PCCU) across Canada. MEASUREMENTS AND RESULTS: All 16 PCCUs participated in the survey with a response rate of 81% (63 physicians). In 14 of 16 centres one to five tracheostomies were performed during 2006. Two centres did not perform any tracheostomies. The overall rate of tracheostomy is less than 1.5%. Percutaneous technique is used in 3/16 (19%) of centres. Readiness to undertake tracheostomy during the first 21[Symbol: see text]days of illness is influenced by patient diagnosis; severe traumatic brain injury 66% vs. 42% in a 2-year-old with Guillain-Barré syndrome, 48% in a 9-year-old with Guillain-Barré syndrome, and 12% in a child with isolated ARDS. In a child with ARDS 25% of respondents would never consider tracheostomy. Age does not affect timing nor keenness for tracheostomy. The majority, 81%, believe that the risks associated with the procedure do not outweigh the potential benefits. Finally, 51% believe that tracheostomy is underutilized in children. CONCLUSIONS: Elective tracheostomy is rarely performed among ventilated children in Canada. However, 51% of physicians believe it is underutilized. The role of elective tracheostomy and the percutaneous technique in children requires further investigation.

Incomplete distal renal tubular acidosis affects growth in children.

BACKGROUND: Incomplete distal renal tubular acidosis (idRTA) is recognized as an underlying aetiology in recurrent nephrolithiasis. Until the recently reported high prevalence of idRTA in adults with osteoporosis, the effect of idRTA on skeletal parameters was not known. We hypothesize that idRTA has a potential to affect height in the paediatric population. METHODS: In a cross-sectional study, the children with posterior urethral valves (PUV), with normal estimated glomerular filtration rates, were evaluated for idRTA and complete dRTA. The idRTA evaluation was done by short ammonium chloride acidification test. The height standard deviation scores (SDS) in the idRTA group were compared with PUV children without dRTA, with complete dRTA, and to age and gender matched controls with no renal issue (n = 50). RESULTS: The idRTA group (n = 17) manifested a significantly lower mean height SDS (-1.94 +/- 0.41 vs -0.46 +/- 0.28; P < 0.001) and a higher short stature prevalence (height SDS below 2) (18% vs 0; P = 0.06) as compared with those without dRTA (n = 23). The matched controls showed a significantly higher height SDS as compared with the idRTA group (-0.39 +/- 0.25 vs -1.94 +/- 0.41; P < 0.001). As compared with the complete dRTA group (n = 9), the children with idRTA did have significantly higher height SDS (-1.94 +/- 0.41 vs -5.31 +/- 1.95; P = 0.002), and a lower short stature prevalence (18% vs 78%; P = 0.001). On multivariate analysis, dRTA was significantly associated with the height SDS (= -0.88; P < 0.001). CONCLUSIONS: Incomplete dRTA affects height in children. This observation needs validation in longitudinal studies.

Have changes in ventilation practice improved outcome in children with acute lung injury?

OBJECTIVES: To describe the changes that have occurred in mechanical ventilation in children with acute lung injury in our institution over the last 10-15 yrs and to examine the impact of these changes, in particular of the delivered tidal volume on mortality. DESIGN: Retrospective study. SETTING: University-affiliated children's hospital. PATIENTS: The management of mechanical ventilation between 1988 and 1992 (past group, n = 79) was compared with the management between 2000 and 2004 (recent group, n = 85). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The past group patients were ventilated with a significantly higher mean tidal volume (10.2 +/- 1.7 vs. 8.1 +/- 1.4 mL.kg actual body weight, p < .001), lower levels of positive end-expiratory pressure (6.1 +/- 2.7 vs. 7.1 +/- 2.4 cm H2O, p = .007), and higher mean peak inspiratory pressure (31.5 +/- 7.3 vs. 27.8 +/- 4.2 cm H2O, p < .001) than the recent group patients. The recent group had a lower mortality (21% vs. 35%, p = .04) and a greater number of ventilator-free days (16.0 +/- 9.0 vs. 12.6 +/- 9.9 days, p = .03) than the past group. A higher tidal volume was independently associated with increased mortality (odds ratio 1.59; 95% confidence interval 1.20, 2.10, p < .001) and reduction in ventilation-free days (95% confidence interval -1.24, -0.77, p < .001). CONCLUSIONS: The changes in the clinical practice of mechanical ventilation in children in our institution reflect those reported for adults. In our experience, mortality among children with acute lung injury was reduced by 40%, and tidal volume was independently associated with reduced mortality and an increase in ventilation-free days.

Secondary abdominal compartment syndrome in a case of pediatric trauma shock resuscitation.

OBJECTIVE: To report a rare case of secondary abdominal compartment syndrome during shock resuscitation in a pediatric trauma patient. DESIGN: Case report and literature review. SETTING: A community hospital and a designated children's trauma hospital. PATIENT: A 17-yr-old trauma patient. INTERVENTIONS: Advanced trauma life support, trauma laparotomy, and superficial temporal artery ligation. MEASUREMENTS AND MAIN RESULTS: A 17-yr-old trauma patient with ongoing blood loss from a lacerated superficial temporal artery received aggressive crystalloid resuscitation before arrival at a designated trauma hospital. His injury severity score was 16. The first hemoglobin drawn was 55 g/L with a hematocrit of 0.16 L/L. Within 3 hrs of the trauma, an abdominal computed tomography scan demonstrated a moderate amount of free peritoneal fluid, edematous bowel with marked enhancement, and a compressed inferior vena cava. Shortly after completion of imaging studies, the patient's abdomen became increasingly tense with poor perfusion to the lower extremities. Urgent laparotomy for abdominal compartment syndrome identified excessive ascites and extensive bowel edema with no blood or traumatic injuries. Abdominal decompression resulted in immediate improvement of hemodynamics and restored lower limb perfusion. Primary abdominal closure was obtained and the patient recovered fully with gentle diuresis. CONCLUSIONS: Secondary abdominal compartment syndrome developed in this pediatric trauma patient with hemorrhagic shock, possibly from aggressive crystalloid resuscitation. This trauma case highlights the importance of early hemorrhagic control with balanced crystalloid/transfusion therapy. Secondary abdominal compartment syndrome in pediatric trauma is rare and may reflect physiologic differences during development, less aggressive resuscitation practices, and/or underrecognition.

Drotrecogin alfa (activated) treatment in a neonate with sepsis and multi organ failure.

The administration of drotrecogin alfa (activated) improves outcome in adult patients with severe sepsis. Since the published pediatric experience with this drug is limited, the role of drotrecogin alfa (activated) in children, and especially in newborns is not well established. We describe a 3-day-old neonate with septic shock and multiorgan system failure, including circulatory, respiratory, renal failure, and disseminated intravascular coagulation, refractory to intensive fluid resuscitation and inotrope support. Within hours of drotrecogin alfa (activated) administration, the neonate experienced dramatic improvement in hemodynamic parameters. The infusion was discontinued after 48 hours, without clinical deterioration. Aside from transient thrombocytopenia, no significant side effects were observed. A brain MRI performed on day 18 after discontinuation of treatment was normal. The positive hemodynamic effect and outcome of treatment in this patient, indicates that drotrecogin alfa (activated) may play a similar role in the treatment of sepsis in neonates as already established in adults.

Lung development and susceptibility to ventilator-induced lung injury.

RATIONALE: Ventilator-induced lung injury has been predominantly studied in adults. OBJECTIVES: To explore the effects of age and lung development on susceptibility to such injury. METHODS: Ex vivo isolated nonperfused rat lungs (infant, juvenile, and adult) were mechanically ventilated where VT was based on milliliters per kilogram of body weight or as a percentage of the measured total lung capacity (TLC). In vivo anesthetized rats (infant, adult) were mechanically ventilated with pressure-limited VTs. Allocation to ventilation strategy was randomized. MEASUREMENTS: Ex vivo injury was assessed by pressure-volume analysis, reduction in TLC, and histology, and in vivo injury by lung compliance, cytokine production, and wet- to dry-weight ratio. MAIN RESULTS: Ex vivo ventilation (VT 30 ml.kg(-1)) resulted in a significant reduction (36.0 +/- 10.1%, p < 0.05) in TLC in adult but not in infant lungs. Ex vivo ventilation (VT 50% TLC) resulted in a significant reduction in TLC in both adult (27.8 +/- 2.8%) and infant (10.6 +/- 7.0%) lungs, but more so in the adult lungs (p < 0.05); these changes were paralleled by histology and pressure-volume characteristics. After high stretch in vivo ventilation, adult but not infant rats developed lung injury (total lung compliance, wet/dry ratio, tumor necrosis factor alpha). Surface video microscopy demonstrated greater heterogeneity of alveolar distension in ex vivo adult versus infant lungs. CONCLUSION: These data provide ex vivo and in vivo evidence that comparable ventilator settings are significantly more injurious in the adult than infant rat lung, probably reflecting differences in intrinsic susceptibility or inflation pattern.