Use of extracorporeal membrane oxygenation for bronchoscopic removal of a tracheal foreign body in a child.

BACKGROUND: Bronchoscopic removal of a foreign body is a common emergency procedure in paediatric otolaryngology. It is potentially life-threatening, as complete airway obstruction caused by the foreign body can lead to hypoxic cardiac arrest during the manipulation of the object. CASE REPORT: This paper presents a child who had aspirated a foreign body that could not be extracted conventionally via rigid bronchoscopy in the first instance. Subsequently, it was extracted at repeat bronchoscopy under controlled respiratory conditions maintained by an extracorporeal gas exchange circuit - extracorporeal membrane oxygenation, using a polypropylene hollow fibre oxygenator commonly employed in cardiac surgery (rather than a more expensive polymethyl pentene oxygenator commonly used in extracorporeal membrane oxygenation). CONCLUSION: Extracorporeal membrane oxygenation use can be considered in exceptional cases of upper airway emergencies, even in resource-poor settings, and can avoid more hazardous thoracotomy and bronchotomy procedures.

The need for thoracic surgery in adult patients receiving extracorporeal membrane oxygenation: a 16-year experience.

OBJECTIVES: Patients on extracorporeal membrane oxygenation (ECMO) are at risk from thoracic complications such as bleeding or pneumothorax, which may subsequently necessitate thoracic surgical intervention. We aimed to: 1) analyse the indication and nature of thoracic surgical intervention in these patients and 2) analyse the effect of a change in the ECMO circuit from roller pump to centrifugal pump on transfusion requirements pre and post thoracotomy. METHODS: We retrospectively reviewed a prospectively collected database of 569 adults put on ECMO between 1995 and 2011. Patients undergoing thoracotomy were identified and outcomes were statistically analysed. RESULTS: Forty thoracotomies were performed in 18 patients [61% male, median age 31 (14-56) years, one bilateral procedure]. The indications for ECMO included: pneumonia 14/18 (78%), trauma 2/18 (11%) and other 2/18 (11%). Median duration on ECMO was 13 (1-257) days and the time to initial thoracotomy was 10 (1-183) days. The indications for thoracotomy were: excessive bleeding post chest drain insertion (11/19, 58%), uncontrolled air leak (9/19, 47%) and pleural effusion (4/19, 21%). The primary operations were 12/19 (63%) evacuation of haemothorax, 3/19 (16%) lung repair, 2/19 (11%) diagnostic lung biopsy and 2/19 (11%) other. Ten patients needed a further 21 thoracotomies (3 lobectomies); average 2 (1-5) per patient. In total, 30/40 (75%) thoracotomies were performed for bleeding complication. The change from roller to centrifugal pump trended towards a reduction in mean transfusion requirements in these patients following thoracotomy (11.5 versus 4 units, p=0.14). The in-hospital mortality was 7/18 (39%) patients. There were no statistically significant predictors of poor outcome. CONCLUSIONS: The need for thoracotomy whilst on ECMO is 3.2% in this large series. Intervention may be complicated, thus, either ECMO specialists should have thoracic training or thoracic surgeons should be on-site. Potential mortality is high and, although not statistically significant, a difference in transfusion requirements was observed following the change of circuit.

Randomised controlled trial and parallel economic evaluation of conventional ventilatory support versus extracorporeal membrane oxygenation for severe adult respiratory failure (CESAR).

OBJECTIVES: To determine the comparative effectiveness and cost-effectiveness of conventional ventilatory support versus extracorporeal membrane oxygenation (ECMO) for severe adult respiratory failure. DESIGN: A multicentre, randomised controlled trial with two arms. SETTING: The ECMO centre at Glenfield Hospital, Leicester, and approved conventional treatment centres and referring hospitals throughout the UK. PARTICIPANTS: Patients aged 18-65 years with severe, but potentially reversible, respiratory failure, defined as a Murray lung injury score > or = 3.0, or uncompensated hypercapnoea with a pH < 7.20 despite optimal conventional treatment. INTERVENTIONS: Participants were randomised to conventional management (CM) or to consideration of ECMO. MAIN OUTCOME MEASURES: The primary outcome measure was death or severe disability at 6 months. Secondary outcomes included a range of hospital indices: duration of ventilation, use of high frequency/oscillation/jet ventilation, use of nitric oxide, prone positioning, use of steroids, length of intensive care unit stay, and length of hospital stay - and (for ECMO patients only) mode (venovenous/veno-arterial), duration of ECMO, blood flow and sweep flow. RESULTS: A total of 180 patients (90 in each arm) were randomised from 68 centres. Three patients in the conventional arm did not give permission to be followed up. Of the 90 patients randomised to the ECMO arm, 68 received that treatment. ECMO was not given to three patients who died prior to transfer, two who died in transit, 16 who improved with conventional treatment given by the ECMO team and one who required amputation and could not therefore be heparinised. Ninety patients entered the CM (control) arm, three patients later withdrew and refused follow-up (meaning that they were alive), leaving 87 patients for whom primary outcome measures were available. CM consisted of any treatment deemed appropriate by the patient's intensivist with the exception of extracorporeal gas exchange. No CM patients received ECMO, although one received a form of experimental extracorporeal arteriovenous carbon dioxide removal support (a clear protocol violation). Fewer patients in the ECMO arm than in the CM arm had died or were severely disabled 6 months after randomisation, [33/90 (36.7%) versus 46/87 (52.9%) respectively]. This equated to one extra survivor for every six patients treated. Only one patient (in the CM arm) was known to be severely disabled at 6 months. Patients allocated to ECMO incurred average total costs of 73,979 pounds compared with 33,435 pounds for those undergoing CM (UK prices, 2005). A lifetime model predicted the cost per quality-adjusted life-year (QALY) of ECMO to be 19,252 pounds (95% confidence interval 7622 pounds to 59,200 pounds) at a discount rate of 3.5%. Lifetime QALYs gained were 10.75 for the ECMO group compared with 7.31 for the conventional group. Costs to patients and their relatives, including out of pocket and time costs, were higher for patients allocated to ECMO. CONCLUSIONS: Compared with CM, transferring adult patients with severe but potentially reversible respiratory failure to a single centre specialising in the treatment of severe respiratory failure for consideration of ECMO significantly increased survival without severe disability. Use of ECMO in this way is likely to be cost-effective when compared with other technologies currently competing for health resources. TRIAL REGISTRATION: Current Controlled Trials ISRCTN47279827.

The inhaled pin inaccessible to the bronchoscope: a management conundrum.

OBJECTIVE: The inhaled sharp foreign body is usually amenable to bronchoscopic extraction. When this fails, management poses a challenge. We present a logical approach to the inhaled pin inaccessible to the bronchoscope. CASE REPORT: A 12-year-old girl presented to the accident and emergency unit after accidentally inhaling a pin. Multiple attempts with both rigid and flexible bronchoscopy failed to access the pin, which had lodged distally in the anteromedial basal segment of the left lung. Eventually, the pin was extracted at thoracotomy. CONCLUSION: We discuss the reasons for extracting such pins, as opposed to leaving them in situ, and when to proceed from endoscopy to open surgery. Such knowledge is useful, not only to guide the multidisciplinary team in their combined approach to this unique challenge, but also to explain to the patient the rationale for the proposed treatment protocol.

Neonatal myocardial infarction and the role of extracorporeal membrane oxygenation.

Acute myocardial infarction is a cause of neonatal collapse. The diagnosis is suggested by ischaemic electrocardiography, raised cardiac enzymes and deteriorating cardiac function and should be considered in severe neonatal cardiac dysfunction without other identifiable causes. This paper presents four cases of neonatal myocardial infarction treated with veno-arterial extracorporeal membrane oxygenation (VA ECMO) for cardiorespiratory support. The paper illustrates that left ventricular function may recover after neonatal myocardial infarction if it can be supported for long enough, and that early ECMO referral may be of benefit.

Neonatal extracorporeal membrane oxygenation: practice patterns and predictors of outcome in the UK.

OBJECTIVE: To review the UK neonatal extracorporeal membrane oxygenation (ECMO) service and identify predictors of outcome. DESIGN: Retrospective review of the national cohort. PATIENTS AND INTERVENTIONS: 718 neonates received ECMO for respiratory failure between 1993 and 2005. MEASUREMENTS AND RESULTS: Diagnoses were: 48.0% meconium aspiration syndrome (97.1% survivors), 15.9% congenital diaphragmatic hernia (CDH; 57.9% survivors), 15.9% sepsis (62.3% survivors), 9.5% persistent pulmonary hypertension (79.4% survivors), 5.6% respiratory distress syndrome (92.5% survivors) and 5.1% congenital lung abnormalities (24.3% survivors). The overall survival rate of 79.7% compared favourably with the worldwide Extracorporeal Life Support Organization (ELSO) Registry. Over the period of review, pre-ECMO use of advanced respiratory therapies increased (p<0.001), but ECMO initiation was not delayed (p = 0.61). The use of veno-venous (VV) ECMO increased (p<0.001) and average run time fell (p = 0.004). Patients treated with VV ECMO had a survival rate of 87.7% compared with 73.4% in the veno-arterial (VA) ECMO group; only 42.4% of those needing conversion from VV to VA ECMO survived. In non-CDH neonates, lower birth weight, lower gestational age, older age at ECMO and higher oxygenation index (OI) were associated with increased risk of death. In CDH neonates, lower birth weight and younger age at ECMO were identified as risk factors for death. CONCLUSION: The UK neonatal ECMO service achieves good outcomes and with overall survival rate reaching 80% compares favourably with international results. Advanced respiratory therapies are used widely in UK ECMO patients. Identification of higher OI and older age at ECMO as risk factors in non-CDH neonates reinforces the importance of timely referral for ECMO.

Pseudocalcification on chest CT scan.

Liquid ventilation with perfluorocarbons is used in severe respiratory failure that cannot be managed by conventional methods. Very little is known about the use of liquid ventilation in paediatric patients with respiratory failure and there are no reports describing the distribution and excretion of perfluorocarbons in paediatric patients with severe respiratory failure. The aim of this report is to highlight the prolonged retention of perfluorocarbons in a paediatric patient, mimicking pulmonary calcification and misleading the interpretation of the chest CT scan. A 10-year-old girl was admitted to our intensive care unit with severe respiratory failure due to miliary tuberculosis. Extracorporeal membrane oxygenation (ECMO) was used to support gas exchange and partial liquid ventilation (PLV) with perfluorodecalin was used to aid in oxygenation, lavage the lungs and clear thick secretions. The patient developed a pneumothorax (fluorothorax) on the next day and PLV was discontinued. Multiple bronchoalveolar lavages were performed to clear thick secretions. With no improvement in lung function over the next month a CT scan of the chest was performed. This revealed extensive pulmonary fibrosis and multiple high attenuation lesions suggestive of pulmonary calcification. To exclude perfluorodecalin as the cause for high attenuation lesions, a sample of perfluorodecalin was scanned to estimate the Hounsfield unit density, which was similar to the density of high attenuation lesions on chest CT scan. High-density opacification should be interpreted with caution, especially following liquid ventilation.

Developmental outcome in newborn infants treated for acute respiratory failure with extracorporeal membrane oxygenation: present experience.

OBJECTIVE: To describe the later health status of newborn infants who received extracorporeal membrane oxygenation (ECMO) for acute respiratory failure in the era after the UK ECMO trial. DESIGN: Prospective follow up study of newborn infants who received ECMO at a single centre between January 1997 and January 2001. SETTING: Departments of ECMO and Paediatric Intensive Care, University Hospitals of Leicester. PATIENTS: All babies who received ECMO within 14 days of birth. INTERVENTIONS: Neurodevelopment screening using the schedule for growing skills-II (SGS-II) assessment tool. MAIN OUTCOME MEASURES: Survival at 12 months of age by disease and functional development at follow up. RESULTS: A total of 145 neonates received ECMO for treatment of respiratory failure. Of these, 108 (75%) were alive at 1 year of age. There were no deaths in children treated for respiratory failure secondary to meconium aspiration syndrome (73/145). Ninety three (86% of survivors) infants attended a follow up visit at 11-19 months postnatal age. Eighty two were classed as normal, seven as having "impairment", and four as having "severe disability". CONCLUSIONS: Most newborn infants with acute respiratory failure treated with ECMO will have a normal neurodevelopment screening assessment at 11-19 months of postnatal age. There is no evidence to suggest that changes in neonatal practice since the UK ECMO trial have led to changes in outcome of infants undergoing ECMO therapy.

Traumatic lung injury treated by extracorporeal membrane oxygenation (ECMO).

BACKGROUND: Conventional mechanical ventilation is the mainstay of treatment for severe respiratory failure associated with trauma. However, when extensive lung injury is present, this technique may not be sufficient to prevent hypoxia, and furthermore, may exacerbate pulmonary damage by barotrauma. Extracorporeal membrane oxygenation (ECMO) has been used successfully in critically ill adult trauma patients and can offer an additional treatment modality. This study reports the use of ECMO in a cohort of adults referred with severe respiratory failure following trauma. METHODS: Retrospective analysis over an 8-year period of all 28 adult patients referred to a single tertiary unit for ECMO support. Survival relative to Injury severity score (ISS), lung injury score (Murray grade), duration of treatment and patient age was evaluated. RESULTS: Twenty of 28 patients who received ECMO with severe trauma related respiratory failure (mean PaO2/FiO2 of 62 mmHg) survived. Most patients had long bone fractures, blunt chest trauma, or combined injuries. Lung injury and injury severity scores, patient age, ECMO duration and oxygenation indices pre-ECMO (PaO2/FiO2) were similar in both the survivor and non-survivor groups. CONCLUSION: A high proportion of trauma patients treated with ECMO for severe lung injury survived. This outcome appears to compare favourably to conventional ventilation techniques and may have a role in patients who develop acute severe respiratory distress associated with trauma.

Predicting outcome in ex-premature infants supported with extracorporeal membrane oxygenation for acute hypoxic respiratory failure.

OBJECTIVE: To identify predictors of outcome in ex-premature infants supported with extracorporeal membrane oxygenation (ECMO) for acute hypoxic respiratory failure. METHODS: Retrospective review of ex-premature infants with acquired acute hypoxic respiratory failure requiring ECMO support in the United Kingdom from 1992 to 2001. Review of follow up questionnaires completed by general practitioners and local paediatricians. RESULTS: Sixty four ex-premature infants (5-10 each year) received ECMO support, despite increased use of advanced conventional treatments over the decade. The most common infective agent was respiratory syncytial virus (85% of cases). Median birth gestation was 29 weeks and median corrected age at the time of ECMO support was 42 weeks. Median ECMO support duration was relatively long, at 229 hours. Survival to hospital discharge and to 6 months was 80%, remaining similar throughout the period of review. At follow up, 60% had long term neurodisability and 79% had chronic pulmonary problems. Of pre-ECMO factors, baseline oxygen dependence, younger age, and inpatient status were associated with non-survival (p < or = 0.05). Of ECMO related factors, patient complications were independently associated with adverse neurodevelopmental outcome and death (p < 0.01). CONCLUSIONS: Survival rates for ex-premature infants after ECMO support are favourable, but patients suffer a high burden of morbidity during intensive care and over the long term. At the time of ECMO referral, baseline oxygen dependence is the most important predictor of death, but no combination of the factors considered was associated with a mortality that would preclude ECMO support.

Extracorporeal life support for children with meningococcal septicaemia.

OBJECTIVE: To describe the short-term outcome of children with meningococcal sepsis treated with extracorporeal membrane oxygenation (ECMO) in a single centre. DESIGN: Retrospective analysis of case notes. SETTING: The Heartlink ECMO Centre, Glenfield Hospital, Leicester. PATIENTS: Eleven children (8 boys) out of a total caseload of 800 patients were treated for meningococcal sepsis with ECMO. INTERVENTIONS: Extracorporeal membrane oxygenation. RESULTS: All children with meningococcal sepsis treated with ECMO had a Glasgow Meningococcal Septicaemia Prognostic Score (GMSPS) > or = 12 (positive predictive risk of death of approximately 90%). Five children had adult respiratory distress syndrome (ARDS) and six had refractory shock with multi-organ dysfunction syndrome (MODS) at presentation for ECMO. All five children in the ARDS group survived, four of five receiving veno-venous (VV-) ECMO therapy. In contrast, only one of six children with refractory shock with MODS survived, all of whom required veno-arterial (VA-) ECMO therapy. CONCLUSIONS: Most children with meningococcal sepsis and severe ARDS can be successfully treated with VV-ECMO. In contrast, children with refractory shock and MODS die despite treatment with VA-ECMO. This report does not resolve whether ECMO therapy offers any advantage over conventional therapy in treating severe meningococcal sepsis.

Pilot investigation of hypothermia in neonates receiving extracorporeal membrane oxygenation.

BACKGROUND: Infants requiring extracorporeal membrane oxygenation (ECMO) support represent a high risk group in terms of cerebral injury. Mild hypothermia both during and after cerebral hypoxic ischaemia appears to be a promising strategy for offering neuroprotection. OBJECTIVE: To investigate whether mild hypothermia was both feasible and safe in infants receiving ECMO as a prelude to any formal assessment of this approach in a randomised trial. METHODS: Twenty infants (body weight less than 5 kg) with severe cardiopulmonary insufficiency, referred for ECMO support at Glenfield Hospital, Leicester, were enrolled in this study. Twenty consecutive infants (compromising four groups of five) were studied. Baseline data were obtained from a control group who were run throughout their course at 37 degrees C. The patients in the next group were managed with a core temperature of 36 degrees C for the first 12 hours of their ECMO run, before being warmed up to 37 degrees C. After successful completion, the next group of five were cared for at 35 degrees C for the first 12 hours, and, there having been no previous complications, the final group were cared for at 34 degrees C for the first 12 hours. Patients were assessed clinically and biologically. In addition to routine laboratory tests, cytokines (interleukin 6, interleukin 8, tumour necrosis factor alpha, and C reactive protein) were measured and coagulation tests (D-dimer, thrombin-antithrombin III complex, plasmin-alpha(2)-antiplasmin complex) were performed serially for five days. RESULTS: There were no significant differences among the four groups in gestational age, birth weight, age at the time of ECMO, Apgar scores at one and five minutes, pH before cannulation, oxygenation index, duration of ECMO, and survival rate to discharge from hospital. No adverse effects of mild hypothermia were found on patient management during ECMO. Laboratory data for up to five days of ECMO also showed no difference among the four groups. CONCLUSION: Mild hypothermia (34 degrees C) for the initial 12 hours of an ECMO run is feasible.

Plasma concentrations of midazolam in neonates receiving extracorporeal membrane oxygenation.

Drug disposition is affected during extracorporeal membrane oxygenation (ECMO). This study investigates the dose-concentration relationship of midazolam in neonates requiring ECMO during continuous infusion into the circuit (extracorporeally; n = 10) and intravenously (n = 10). Data on hourly doses and sedation scores were collected for 120 hours. Plasma concentrations were analyzed at times 0, 2, 4, 6, 12, 18, and 24, and every 12 hours thereafter. Both groups were clinically similar. Mean (standard deviation) dose for all patients was 250 (185) microg/kg/h, four times greater than previously reported. Doses administered in the first 24 hours were significantly greater extracorporeally [361 (300)] compared with intravenous [258 (190) microg/kg/h, p < 0.001]. Mean (standard deviation) plasma concentrations in all patients at 24, 48, and 72 hours were 1.4 (0.9), 1.8 (1.2), and 2.6 (1.8) microg/ml, respectively. Satisfactory sedation levels were achieved in all patients. Comparison of the actual observed with predicted (simulated) midazolam concentrations suggested significant attenuation of plasma levels during the first 24 hours of ECMO. However, at 48 hours, observed concentrations exceeded those predicted, suggesting accumulation. We conclude that in the first 24 hours of ECMO, because of an expanded circulating volume and sequestration by the circuit, significantly more midazolam is required to achieve adequate sedation. Subsequently, and because of circuit saturation, maintenance doses should be reduced.

Population pharmacokinetics of theophylline during paediatric extracorporeal membrane oxygenation.

AIMS: To determine the population pharmacokinetics of theophylline during extracorporeal membrane oxygenation (ECMO) from routine monitoring data. METHODS: Retrospective data were collected from 75 term neonates and children (age range 2 days to 17 years) receiving continuous infusions of aminophylline (mean rate 9.2 +/- 2.6 micro g kg-1 min-1) during ECMO. A total of 160 plasma concentrations (range 1-8 per patient), sampled at time intervals ranging from 10 h to 432 h, were included. Population PK analysis and model building were carried out using WinNonMix Professional (Version 2.0.1). Cross-validation was used to evaluate the validity and predictive accuracy of the model. RESULTS: A one-compartment model with first order elimination combined with an additive error model was found to best describe the data. Of the covariables tested, bodyweight significantly influenced clearance and volume of distribution, whereas age was an important determinant of clearance, as adjudged by the differences in the -2 x log likelihood (P < 0.005) and the residual error value. The final model parameters were estimated as: clearance (l h-1) = 0.023 x bodyweight (kg) + 0.000057 x age (days) and volume of distribution (l) = 0.57 x bodyweight (kg). The interindividual variability in clearance and volume of distribution was 38% and 40%, respectively. The residual error corresponded to a standard deviation of 3.6 mg l-1. Cross-validation revealed a median (95% confidence interval) model bias of 9.4% (2.9, 16.5%) and precision of 29.5% (24.8, 36.0%). CONCLUSIONS: The estimated clearance is significantly lower, and volume of distribution higher, than previously reported in non-ECMO patients of similar age. These differences are probably a result of the expanded circulating volume during ECMO and altered renal and hepatic physiology in this critically ill group. Large interindividual variability reflects the heterogeneous nature of patients treated on ECMO.

Surgical closure of atrial septal defects in adults: effect of age at operation on outcome.

OBJECTIVE: To determine whether age has an effect on the long term outcome after surgical closure of atrial septal defects in patients aged 35 years and over. METHODS: Retrospective analysis of 89 patients (64 women) operated on between 1989 and 1999. Patients were divided into two age groups: group I (aged 35-50 years, n = 51) and group II (> 50 years, n = 38). Follow up was between 1-11 years. RESULTS: One operative death and two late deaths occurred in the study period (both in group II). Preoperatively, 29 (57%) patients were in New York Heart Association functional class III-IV in group I compared with 22 (58%) patients in group II (NS). After operation, 44 (86.2%) patients in group I were found to be in class I-II compared with 25 (71.5%, p < 0.05) in group II. Group I patients had a lower incidence of preoperative atrial fibrillation than those in group II (12 (23.5%) v 17 (43.6%), p < 0.05) and only four (7.8%) patients in group I were in atrial fibrillation requiring long term warfarin after surgery compared with 12 (34%, p < 0.05) in group II. Furthermore, echocardiography showed a greater reduction in right ventricular dimension in group I patients (mean (SD) 4.26 (0.82) v 2.71 (0.41) cm, p < 0.001) than in group II patients (4.36 (0.43) v 3.87 (0.29) cm, p = 0.21). No residual intracardiac shunts were identified during follow up. CONCLUSIONS: Surgical closure of atrial septal defects in adult patients can improve clinical status and prevent right ventricular dilatation. The greatest benefit is seen in younger patients.

Risk factors for intestinal ischaemia in cardiac surgical patients.

OBJECTIVE: Mesenteric ischaemia is an uncommon (<1%) but serious complication of cardiac surgery associated with a mortality >50%. Predictors of this complication are not well defined, and diagnosis can be difficult and prompt surgical intervention can be lifesaving. METHODS AND RESULTS: In a retrospective case-note analysis from May 1994 through to May 2000, we identified mesenteric ischaemia in 39 of 5349 consecutive patients (0.07%) undergoing cardiac surgery with cardiopulmonary bypass. By logistic multivariate analysis, we have identified six possible predictors of intestinal ischaemia: duration of cross-clamp, use of significant inotropic support, intra-aortic balloon counterpulsation for low cardiac output, need for blood transfusions, triple vessel disease and peripheral vascular disease. In all patients a combination of four predictors were present. Patients who survived this complication had surgical intervention earlier (6.4+/-3.8 h) than those who did not (16.9+/-10 h). CONCLUSIONS: The diagnosis and prompt treatment of mesenteric ischaemia post cardiac surgery requires a high degree of awareness. These predictors may be useful in alerting medical staff to the possibility of gastro-intestinal ischaemic complications after cardiac surgery particularly that early surgical intervention reduces mortality.

Repeatability of cellular constituents and cytokine concentration in fluid obtained by non-bronchoscopic bronchoalveolar lavage of infants receiving extracorporeal oxygenation.

BACKGROUND: Since few studies have assessed the repeatability of non-bronchoscopic bronchoalveolar lavage (NB-BAL), we compared cellular counts and cytokine concentrations in fluid obtained by standardised NB-BAL from each side of 20 intubated infants receiving extracorporeal membrane oxygenation (ECMO). METHODS: Total cell counts were obtained from 95 paired lavages and 77 pairs were suitable for differential counts and measurement of cytokine concentrations. RESULTS: Moderate correlation was noted between the two sides for most cell types including total cell counts and percentages of neutrophils and macrophages (R=0.70-0.84) and for cytokine concentrations (IL-8 R=0.78, IL-6 R=0.75, TNF-alpha R=0.64, all p< or =0.001). Using Bland-Altman analysis the mean difference between the two sides approached zero for cellular constituents (total cell counts mean difference 1.7, limits of agreement -187.5 to +190.9 x 10(4)/ml; percentage neutrophils -3.9%, -41.5% to +33.6%; percentage macrophages 3.9%, -33.8% to +41.6%) but tended to be greater on the right for logarithmically transformed cytokine measurements (IL-8: left/right ratio 0.74, limits of agreement 0.12 to 5.45, IL-6: 0.93, 0.09 to 5.87, and TNF-alpha: 0.93, 0.27 to 3.16). Using linear regression with random effects to assess the variability, only the infant's age appeared to influence the cellular results but, for cytokines, only the volume retrieved affected the variability. The magnitude of the measurements, the underlying disease, the operator's experience, days on ECMO, or survival did not affect the variability. CONCLUSION: Measurements obtained by NB-BAL need to be interpreted with caution and strongly suggest that normalisation for the dilutional effects of saline is essential.

Floating thrombus in the aorta.

A review of the literature shows that there are few reported cases of embolism or thrombus in a nonaneurysmal, effectively normal aorta with no other underlying reason for thrombus formation in the aorta. We report a case of a large, floating thrombus in the descending aorta lumen and discuss surgical and management options.

Post-pneumonectomy video-assisted thoracoscopic bullectomy using extra-corporeal membrane oxygenation.

We describe a case of a patient who, 14 years after a pneumonectomy, required surgery for a life-threatening air-leak following accidental intubation of an emphysematous bulla in his remaining lung. To facilitate treatment by video-assisted thoracoscopic surgery, veno-venous extra-corporeal membrane oxygenation was employed.