Use of multi-strain probiotics in linseed meal based diet for Labeo rohita fingerlings

Unavailability of probiotics in fish digestive system fingerlings is unable to digest and absorb their food properly. The current research was conducted to investigate the influence of probiotics added Linseed meal based (LMB) diet on hematology and carcass composition of Labeo rohita juveniles. Hematological parameters are essential diagnostics used to estimate the health status of fish. The usage of probiotics for fish health improvement is becoming common due to the higher demand for environment-friendly culture system in water. Linseed meal was used as a test ingredient to prepare six experimental test diets by adding probiotics (0, 1, 2, 3, 4 and 5 g/kg) and 1% indigestible chromic oxide for seventy days. According to their live wet weight, five percent feed was given to fingerlings twice a day. Fish blood and carcass samples (Whole body) were taken for hematological and carcass analysis at the end of the experiment. The highest carcass composition (crude protein; 18.72%, crude fat; 8.80% and gross energy; 2.31 kcal/g) was observed in fish fed with test diet II supplemented with probiotics (2 g/kg). Moreover, maximum RBCs number (2.62× 106mm-3), WBCs (7.84×103mm-3), PCV (24.61), platelets (63.85) and hemoglobin (7.87) had also been reported in the fish fingerlings fed on 2 g/kg of probiotics supplemented diet. Results indicated that probiotics supplementation has a critical role in improvement of fingerlings' body composition and hematological indices. Present findings showed that probiotics supplementation at 2 g/kg level in linseed by-product-based diet was very useful for enhancing the overall performance of L. rohita fingerlings.

Treatment of Polypharmacy Overdose with Multimodality Extracorporeal Life Support

A 45-year-old woman presented to the emergency department of a tertiary referral hospital after taking an overdose of verapamil, doxepin, quetiapine, diazepam, temazepam, and clonazepam. She rapidly developed shock refractory to pharmacological support and was placed on percutaneous venoarterial extracorporeal membrane oxygenation (ECMO). She had a severe metabolic acidosis from a combination of shock and drug intoxication that improved with continuous venovenous haemodialysis. Forty-eight hours after presentation, while still on ECMO, the patient had complete cardiac standstill for three and a half hours, attributable to slow-release verapamil, that resolved after the commencement of plasmapheresis. The role of plasmapheresis in verapamil overdose requires further study.

Bilaterally Absent Pupillary Responses: Not Always a Bad Sign

Pupillary responses are a simple test commonly used as a predictor of outcome after severe brain injury. It is also common for clinicians to associate bilaterally absent pupillary responses with very poor prognosis. We report a series of cases of severely brain injured children with bilaterally absent pupillary responses who had favourable outcomes. From a group of 89 patients with brain injury, 32 had bilaterally absent pupillary responses and six (four with traumatic brain injury and two with infective brain injury) subsequently had favourable outcomes. This represents 18.8% of patients and should be a reminder to clinicians that the clinical sign of bilaterally absent pupillary responses is not always associated with a hopeless outcome.

Successful Use of ECMO in Adults with Life-threatening Infections

Two cases of critically ill patients who received extracorporeal membrane oxygenation (ECMO) using different forms of circuitry and for different indications are presented. Both patients had life-threatening infections with septic shock and were not able to be supported by conventional means. The first patient had staphylococcal septicaemia and received venoarterial ECMO for circulatory failure. The second patient had psittacosis and received venovenous ECMO for respiratory failure. We discuss the expanding indications for this technology and the role it has to play in adult intensive care.

Did microbial larviciding contribute to a reduction in malaria cases in eastern Botswana in 2012-2013?

Setting: Larviciding has potential as a component of integrated vector management for the reduction of malaria transmission in Botswana by complementing long-lasting insecticide nets and indoor residual sprays. Objective: To evaluate the susceptibility of local Anopheles to commonly used larvicides. Design: This field test of the efficacy of Bacillus thuringiensis subsp. israliensis vs. Anopheles was performed by measuring larval density before treatment and 24 h and 48 h after treatment in seven sites of Bobirwa district, eastern Botswana, in 2012 and 2013. Vector density and malaria cases were compared between Bobirwa and Ngami (northwestern Botswana), with no larviciding in the control arm. Results: Larviciding reduced larval density by 95% in Bobirwa in 2012, with two cases of malaria, while in 2013 larval density reduction was 81%, with 11 cases. Adult mosquito density was zero for both years in Robelela village (Bobirwa), compared to respectively four and 26 adult mosquitoes per room in Shorobe village (Ngami) in 2012 and 2013. There were no cases of malaria in Robelela in either year, but in Shorobe there were 20 and 70 cases, respectively, in 2012 and 2013. Conclusion: Larviciding can reduce the larval density of mosquitoes and reduce malaria transmission in Botswana. Large-scale, targeted implementation of larviciding in districts at high risk for malaria is recommended.

Advances in malaria elimination in Botswana: a dramatic shift to parasitological diagnosis, 2008-2014

Background: Malaria elimination requires infection detection using quality assured diagnostics and appropriate treatment regimens. Although Botswana is moving towards malaria elimination, reports of unconfirmed cases may jeopardise this effort. This study aimed to determine the proportion of cases treated for malaria that were confirmed by rapid diagnostic testing (RDT) and/or microscopy. Methods: This was a retrospective descriptive study using routine national data from the integrated disease surveillance and case-based surveillance systems from 2008 to 2014. The data were categorised into clinical and confirmed cases each year. An analysis of the data on cases registered in three districts that reported approximately 70% of all malaria cases was performed, stratified by year, type of reporting health facilities and diagnostic method. Results: During 2008-2014, 50 487 cases of malaria were reported in Botswana, and the proportion of RDT and/or blood microscopy confirmed cases improved from 6% in 2008 to 89% in 2013. The total number of malaria cases decreased by 97% in the same period, then increased by 41% in 2013. Conclusion: This study shows that malaria diagnostic tests dramatically improved malaria diagnosis and consequently reduced the malaria burden in Botswana. The study identified a need to build capacity on microscopy for species identification, parasite quantification and guiding treatment choices.

Driving towards malaria elimination in Botswana by 2018: progress on case-based surveillance, 2013-2014

Background: Reliable information reporting systems ensure that all malaria cases are tested, treated and tracked to avoid further transmission. Botswana aimed to eliminate malaria by 2018, and surveillance is key. This study focused on assessing the uptake of the new malaria case-based surveillance (CBS) system introduced in 2012, which captures information on malaria cases reported in the Integrated Disease Surveillance and Response (IDSR) system. Methods: This was a retrospective descriptive study based on routine data focusing on Ngami, Chobe and Okavango, three high-risk districts in Botswana. Aggregated data variables were extracted from the IDSR and compared with data from the CBS. Results: The IDSR reported 456 malaria cases in 2013 and 1346 in 2014, of which respectively only 305 and 884 were reported by the CBS. The CBS reported 34% fewer cases than the IDSR system, indicating substantial differences between the two systems. The key malaria indicators with the greatest variability among the districts included in the study were case identification number and date of diagnosis. Conclusion: The IDSR and CBS systems are essential for malaria elimination, as shown by the significant gaps in reporting between the two systems. These findings highlight the need for further investigation into these discrepancies. Strengthening the CBS system will help to reach the objective of malaria elimination in Botswana.

Impact of thrombelastography in paediatric intensive care

We assessed the clinical impact of thrombelastography (TEG®) results (TEG® 5000, Haemonetics Corporation, Braintree, MA, USA) by measuring their ability to cause changes in a theoretical treatment plan and contribute to the understanding of haemostasis. We prospectively included paediatric intensive care unit (PICU) patients who had standard tests of haemostasis and TEG ordered and had an arterial catheter or extracorporeal access port in situ. Blood for standard tests and TEG was taken simultaneously. Independent of patient care, general patient information and results of standard laboratory tests were presented to five clinicians who were asked to document their theoretical treatment plan. Clinicians were then shown TEG results and asked if they caused a change in their plan, if they confirmed initial standard laboratory test results, if they enabled a better understanding of haemostasis and if they provided additional information. Inter-rater agreement between the clinicians was determined. Forty-two TEG results were obtained from 34 patients. Overall, the inclusion of TEG results led to a change in treatment plan in 97 of 207 occasions (47%), confirmed standard laboratory test results in 177 of 204 occasions (87%), enabled a better understanding of haemostasis in 140 of 204 occasions (69%) and provided additional information in 131 of 204 occasions (64%). Variation existed between clinicians, seemingly due to individual differences, with poor inter-rater agreement. We conclude that TEG results led to changes in treatment plans almost half the time, confirmed findings of standard tests and provided a better understanding of haemostasis, but randomised controlled trials are required to determine the role and influence of TEG results on patient outcome.

Anaesthetists stress is induced by patient ASA grade and may impair non-technical skills during intubation

BACKGROUND

The aims of this study were to determine if patient ASA grade was associated with increased stress in anaesthetists with a subsequent effect on non-technical skills.

METHODS

Stress was measured using a validated objective (heart rate variability or heart rate) and subjective tool. We studied eight consultant anaesthetists at baseline (rest) and during 16 episodes of intubation with an ASA 1 or 2 patient vs. an ASA 3 or 4 patient. The primary outcome for the study was objective and subjective stress between both patient groups. Secondary outcomes were non-technical skill ratings and the association between stress measurements.

RESULTS

ASA 3 or 4 patients were associated with increases in objective stress when compared to baseline (mean 4.6 vs. 6.7; P = 0.004). However, ASA 1 or 2 patients were not associated with increases in stress when compared to baseline (mean 4.6 vs. 4.7; P = 1). There was no significant difference in subjective stress between the groups (P = 0.18). Objective stress negatively affected situational awareness (P = 0.03) and decision-making (P = 0.03); however, these did not decline to a clinically significant threshold. Heart rate variability (r = 0.60; P = 0.002) better correlated with subjective stress when compared to heart rate (r = 0.30; P = 0.15). Agreement between raters for Anaesthetic Non-Technical Skills (ANTS) scores was acceptable (ICC = 0.51; P = 0.003).

CONCLUSION

This study suggests that higher patient ASA grade can increase stress in anaesthetists, which may impair non-technical skills.

Intensive care management of children intubated for croup: a retrospective analysis

Croup remains the commonest reason for acute upper airway obstruction in children, yet there are scarce contemporary data of airway management in those requiring intubation. We performed a retrospective analysis of the intensive care management of children intubated for croup in two quaternary Paediatric Intensive Care Units: Royal Children's Hospital Melbourne, Australia and Alberta Children's Hospital Calgary, Canada. Patients intubated for less than three days were compared with those intubated for greater than three days. Patients less than 10 kg body weight were compared to those greater than 10 kg. Demographic, clinical and microbiological data were recorded. Seventy-seven cases of croup requiring intubation were identified. The median duration of intubation was 60 hours. Parainfluenza was the most common viral aetiology, detected in 30% of cases. Antibiotics were prescribed in 51% of patients. Corticosteroids were prescribed pre intubation in two-thirds of patients and all post intubation, with the median dose being prednisolone 3 mg/kg/day. Primary extubation failure occurred in 6.5% of patients. Neither the duration of intubation nor patient size were associated with extubation failure. An air leak test was performed in 69% of patients and poorly predicted extubation success. One non-urgent tracheostomy was performed and there was one death from hypoxic ischaemic encephalopathy. Endotracheal tube leak is poorly recorded and may not predict successful extubation.

The meaning of a high plasma free haemoglobin: retrospective review of the prevalence of haemolysis and circuit thrombosis in an adult ECMO centre over 5 years

AIMS

In adults requiring extracorporeal membrane oxygenation (ECMO), we wanted to determine; i) the frequency of elevated plasma free haemoglobin (PFHb), ii) the reasons for circuit changes and iii) whether elevated PFHb was associated with higher in-hospital mortality.

MATERIALS AND METHODS

Patients requiring ECMO between January 2010 and August 2014 were identified from a prospectively collected ECMO database. Their scanned medical records and pathology results were reviewed. Relevant patient, biochemical and circuit data were collected on an Excel spreadsheet and analysed using Stata 13 (StataCorp, College Station, TX). The patients were analysed in three groups, depending on their peak PFHb during ECMO: 'Normal PFHb' (<0.1 g/L), 'Low level PFHb' (0.1 - 0.5 g/L), 'High level PFHb' (>0.5 g/L).

MAIN RESULTS

There were 184 ECMO runs (56 VV, 128 VA) - 61 'Normal PFHb', 99 'Low level PFHb', 24 'High level PFHb'. Circuit thrombosis (pump, oxygenator) or haemolysis requiring exchanges were significantly more common in VV ECMO compared to VA ECMO - 23.21% (13/56) vs. 0.78% (1/128), p<0.001. Elevated PFHb was associated with a longer duration of haemofiltration (p<0.001) and ECMO support (p<0.001). In-hospital mortality rates for the 'Normal PFHb', 'Low level PFHb' and 'High level PFHb' groups were 16.39% (10/61), 30.30% (30/99) and 37.50% (9/24), respectively, p=0.067.

CONCLUSION

Elevated PFHb values during adult ECMO were common. Severe haemolysis or thrombosis requiring circuit changes were uncommon and occurred almost exclusively on VV ECMO. There was a non-statistically significant increase in in-hospital mortality with elevated PFHb and studies of larger registry data may clarify the prognostic value of PFHb in adult patients.

Relationship of ECMO duration with outcomes after pediatric cardiac surgery: a multi-institutional analysis

BACKGROUND

There are very sparse data on the outcomes of children receiving prolonged extracorporeal membrane oxygenation (ECMO) after cardiac surgery. This study was aimed to evaluate the association of ECMO duration with outcomes in children undergoing surgery for congenital heart disease using the Pediatric Health Information System (PHIS) database.

METHODS

Patients aged ≤18 years receiving ECMO after pediatric cardiac surgery (with or without cardiopulmonary bypass) at a PHIS-participating hospital (2004-2013) were included. De-identified data obtained from retrospective, observational dataset included demographic information, baseline characteristics, pre-ECMO risk factors, operation details, patient diagnoses, and center data. Outcomes evaluated included in-hospital mortality, length of mechanical ventilation, length of ICU stay, length of hospital stay, and hospital charges. Cox proportional hazards models were fitted to study the probability of study outcomes as a function of ECMO duration.

RESULTS

Nine hundred ninety-eight patients from 37 hospitals qualified for inclusion. The median duration of ECMO run was 4 days (IQR: 1.7). After adjusting for patient and center characteristics, there was 12% increase in the odds of mortality for every 24 hours increase in ECMO duration (OR: 1.12, 95% CI: 1.07-1.18, P<0.001). Patients receiving longer duration of ECMO were associated with longer length of mechanical ventilation, longer length of ICU stay, longer length of hospital stay, and higher hospital charges.

CONCLUSION

Data from this large multicenter database suggest that longer duration of ECMO support after pediatric cardiac surgery is associated with worsening outcomes.

Extracorporeal membrane modality conversions

We report the case of a patient with cardiovascular and respiratory failure due to severe anaphylaxis requiring multiple extracorporeal membrane oxygenation (ECMO) cannulation strategies to provide adequate oxygen delivery and ventilatory support during a period of rapid physiological change. ECMO provides partial or complete support of oxygenation-ventilation and circulation. The choice of which ECMO modality to use is governed by anatomical (vessel size, cardiovascular anatomy and previous surgeries) and physiological (respiratory and/or cardiac failure) factors. The urgency with which ECMO needs to be implemented (emergency cardiopulmonary resuscitation (eCPR), urgent, elective) and the institutional experience will also influence the type of ECMO provided. Here we describe a 12-year-old schoolgirl who, having been resuscitated with peripheral veno-venous (VV) ECMO for severe hypoxemia due to status asthmaticus in the setting of acute anaphylaxis, required escalation to peripheral veno-arterial (VA) ECMO for precipitous cardiovascular deterioration. Insufficient oxygen delivery for adequate cellular metabolic function and possible cerebral hypoxia due to significant differential hypoxia necessitated ECMO modification. After six days of central (transthoracic) VA ECMO support and 21 days of intensive care unit (ICU) care, she made a complete recovery with no neurological sequelae. The use of ECMO support warrants careful consideration of the interplay of a patient's pathophysiology and extracorporeal circuit dynamics. Particular emphasis should be placed on the potential for mismatch between cardiovascular and respiratory support as well as the need to meet metabolic demands through adequate cerebral, coronary and systemic oxygenation. Cannulation strategies occasionally require alteration to meet and anticipate the patient's evolving needs.

ICP and CPP: excellent predictors of long term outcome in severely brain injured children

OBJECTIVE

To determine the predictive powers of intracranial pressure (ICP) and cerebral perfusion pressure (CPP) amongst severely brain injured children.

MATERIALS AND METHODS

ICP and CPP were recorded from thirty-five severely brain injured children who were prospectively recruited after admission to paediatric intensive care. Twenty-five suffered traumatic brain injury (TBI) and ten suffered non-TBI. Peak ICP and minimum CPP recorded for each patient during their admission were related to 5 year Glasgow Outcome Scale outcome. Receiver operator characteristic curves determined that the optimum threshold for unfavourable outcome prediction was >or=40 mmHg for ICP and <or=49 mmHg for CPP. At these thresholds the sensitivity/specificity pairs for the prediction of unfavourable outcome were 33.3/100% and 55.6/100% for ICP and CPP, respectively, amongst patients suffering TBI and were 46.2/100% and 66.2/100% for ICP and CPP, respectively, amongst all patients.

CONCLUSION

ICP and CPP are accurate predictors of unfavourable outcome.

A prospective study of outcome predictors after severe brain injury in children

OBJECTIVE

To directly compare the predictive powers of somatosensory evoked potentials (SEPs) to those of motor and pupillary responses.

DESIGN AND SETTING

Prospective clinical study in a paediatric intensive care unit.

PATIENTS AND PARTICIPANTS

102 severely brain-injured children less than 15 years of age.

MEASUREMENTS AND RESULTS

SEPs and motor and pupillary responses were serially recorded during the first 9 days after admission. Initial, last and those tests performed on or after day 2 were analysed. Outcome was assessed 5 years after injury. SEPs had equal or superior predictive statistics and ROC curves compared to the other tests with few exceptions. Pupillary responses had higher sensitivity for favourable outcome prediction while for unfavourable outcome prediction the last motor responses had higher sensitivity, and the last pupillary responses had slightly higher specificity. Combining SEPs and motor responses provided the best combination for predicting unfavourable outcome.

CONCLUSIONS

SEPs are the best overall predictor of outcome while motor and pupillary responses have advantages in some specific areas. The routine use of SEPs should be considered in the prediction of outcome of severely brain-injured patients.

Are somatosensory evoked potentials the best predictor of outcome after severe brain injury? A systematic review

OBJECTIVE

Many tests have been used to predict outcome following severe brain injury. We compared predictive powers of clinical examination (pupillary responses, motor responses and Glasgow Coma Scale, GCS), electroencephalography (EEG) and computed tomography (CT) to that of somatosensory evoked potentials (SEPs) in a systematic review.

MATERIALS AND METHODS

Medline (1976-2002) and Embase (1980-2002) were searched, manual review of article reference lists was conducted, and authors were contacted. We selected 25 studies addressing the prediction of outcome after severe brain injury using SEPs and either GCS, EEG, CT, pupillary or motor responses. Outcomes were determined for patients with normal or bilaterally absent SEPs and graded measures of GCS, EEG, CT, pupillary responses or motor responses. For favourable outcome prediction SEPs were superior in sensitivity, specificity and positive and negative predictive values, except for pupillary responses which had superior sensitivity and GCS which had higher specificity. SEPs had superior summary receiver operating characteristic curves, with the exception of motor responses, and superior ratio of odds ratios. For unfavourable outcome prediction SEPs were superior to the other tests in sensitivity, specificity and positive and negative predictive values, except for motor and pupillary responses, GCS and CTs which had superior sensitivity. All SEP summary receiver operating characteristic curves and pooled ratio of odds ratios were superior.

CONCLUSIONS

Although imperfect, SEPs appear to be the best single overall predictor of outcome. There is sufficient evidence for clinicians to use SEPs in the prediction of outcome after brain injury.

Partial liquid ventilation and nitric oxide in experimental acute lung injury

OBJECTIVE

To investigate the effects of inhaled nitric oxide (iNO) and partial liquid ventilation (PLV) on oxygenation and pulmonary haemodynamics in acute lung injury (ALI), and to assess their effects on lung function, systemic haemodynamics and lung injury.

METHODS

Using saline lung lavage, ALI was induced in 18 piglets. A control group was ventilated with conventional mechanical ventilation (CMV) for 2 h. An iNO-first group received iNO for the first hour and then iNO with PLV. A PLV-first group received PLV for the first hour and then PLV with iNO. Variables were measured at baseline, 5 min postlavage, and at 1 h and 2 h postlavage.

RESULTS

During the first hour, both treatment groups showed improvement in oxygenation index (OI). At 2 h, the dif-ferences in OI were statistically significant (P = 0.037), with a mean +/- SD of 23.8 +/- 20.7 in the control group, 4.4 +/- 0.9 in the PLV-first group and 6.5 +/- 3.1 in the iNO-first group. The OI was similar in both treatment groups (P = 0.178). At 2 h, the pulmonary artery pressure (PAP) was significantly different (P = 0.04) between groups, with a mean +/- SD PAP of 36.3 +/- 7.2 mmHg in the control group, 27.4 +/- 4.0 mmHg in the PLV-first group and 30.0 +/- 4.1 mmHg in the iNO-first group. The PAP was similar in both treatment groups (P = 0.319).

CONCLUSION

In ALI, oxygenation and pulmonary hypertension are improved with PLV and iNO given together, regardless of the order in which they are commenced.

Partial liquid ventilation compared with conventional mechanical ventilation in an experimental model of acute lung injury

OBJECTIVE

To compare the effects of partial liquid ventilation with conventional mechanical ventilation on oxygenation and pulmonary mechanics in saline lavaged rabbits.

METHODS

Following acute lung injury (saline-lavage), rabbits were assigned to continue conventional mechanical ventilation (n = 6) or commence partial liquid ventilation (n = 6). In both groups the inspired oxygen concentration was 100% throughout the study. The target PaCO2 of 40-60 mmHg was accomplished by keeping the tidal volume between 7 and 10 mL/kg. During the study the peak inspiratory pressure was adjusted to maintain the target PaCO2. Arterial blood gases were taken pre-lavage, immediately post-lavage (time = 0) and then hourly for 5 hours. Pulmonary mechanics were estimated by measuring compliance and resistance. Pulmonary function was measured pre-lavage, immediately post-lavage and at 1 and 5 hours. At 5 hours the rabbits were killed and the lungs were removed for histological examination.

RESULTS

Baseline PaO2, compliance and resistance were not significantly different between groups. The partial liquid ventilation group had a higher PaO2 and a significantly better oxygenation index one hour after commencing partial liquid ventilation and a significantly higher PaO2 averaged over the three hours post-treatment. There were no significant differences in compliance, resistance or lung damage scores.

CONCLUSIONS

In this experimental model of acute lung injury, partial liquid ventilation resulted in immediate and sustained increase in PaO2 over 3 hours without significant change in lung mechanics or histological lung damage.

Septic shock

Infection is problematic because it affects many patients (adults and children), is a major cause of death in intensive care units (ICU) worldwide, and uses a large amount of hospital resources. The mortality rate among patients with septic shock varies but approximates 40% in infected patients admitted to ICUs. Because of the large number of adults dying of sepsis, many resources are expended. Children are physiologically different from adults, but nonetheless, many similarities exist with respect to the response to septic shock.

Delivery across the blood-brain barrier of antisense directed against amyloid beta: reversal of learning and memory deficits in mice overexpressing amyloid precursor protein

Amyloid beta protein (Abeta) may play a causal role in Alzheimer's disease. Previous work has shown that the learning and memory deficits that develop with aging in SAMP8 mice, a strain that overproduces Abeta, can be reversed with i.c.v. injections of an Abeta antisense phosphorothiolate oligonucleotide (Olg). Here, we showed that Olg radioactively labeled with (32)P (P-Olg) was transported intact across the blood-brain barrier (BBB) of mice by a saturable system, termed oligonucleotide transport system-1 (OTS-1). Multiple-time regression analysis found a blood-to-brain unidirectional influx rate for P-Olg of 1.4 +/- 0.39 microl/g-min and capillary depletion showed that P-Olg completely crossed the BBB to enter the parenchymal space of the brain. P-Olg was also shown to enter the cerebrospinal fluid. Transport was especially high into the hippocampus, with the percentage of the i.v. dose taken up by each gram of brain (0.865 +/- 0.115%) being about 1/100 of the i.c.v. dose. An i.v. dose of Olg 100 times that of the effective i.c.v. dose reversed the learning and memory deficits of aged SAMP8 mice. These studies show for the first time that phosphorothiolate oligonucleotides can be delivered to the brain in effective doses by intravenous administration.

A randomized trial of very early decompressive craniectomy in children with traumatic brain injury and sustained intracranial hypertension

OBJECT

The object of our study was to determine, in children with traumatic brain injury and sustained intracranial hypertension, whether very early decompressive craniectomy improves control of intracranial hypertension and longterm function and quality of life.

METHODS

All children were managed from admission onward according to a standardized protocol for head injury management. Children with raised intracranial pressure (ICP) were randomized to standardized management alone or standardized management plus cerebral decompression. A decompressive bitemporal craniectomy was performed at a median of 19.2 h (range 7.3-29.3 h) from the time of injury. ICP was recorded hourly via an intraventricular catheter. Compared with the ICP before randomization, the mean ICP was 3.69 mmHg lower in the 48 h after randomization in the control group, and 8.98 mmHg lower in the 48 hours after craniectomy in the decompression group (P=0.057). Outcome was assessed 6 months after injury using a modification of the Glasgow Outcome Score (GOS) and the Health State Utility Index (Mark 1). Two (14%) of the 14 children in the control group were normal or had a mild disability after 6 months, compared with 7 (54%) of the 13 children in the decompression group. Our conclusion was that when children with traumatic brain injury and sustained intracranial hypertension are treated with a combination of very early decompressive craniectomy and conventional medical management, it is more likely that ICP will be reduced, fewer episodes of intracranial hypertension will occur, and functional outcome and quality of life may be better than in children treated with medical management alone (P=0.046; owing to multiple significance testing P <0.0221 is required for statistical significance). This pilot study suggests that very early decompressive craniectomy may be indicated in the treatment of traumatic brain injury.

Review of the use of somatosensory evoked potentials in the prediction of outcome after severe brain injury

OBJECTIVE

Review the predictive powers of somatosensory evoked potentials (SEPs) in severe brain injury.

DATA SOURCES

Publications in the scientific literature, manual review of article bibliographies, and questioning workers in the field.

STUDY SELECTION

Studies addressing the prediction of outcome after severe brain injury using SEPs.

DATA EXTRACTION

To determine the outcome of patients with either normal or bilaterally absent SEPs as categorized using the Glasgow Outcome Scale into favorable outcomes (good or moderate disability) or unfavorable outcomes (severe disability, vegetative, or dead). Studies were included if they were in English and allowed the determination of outcomes for all patients with normal or bilaterally absent SEPs. Papers were not considered if subjects were neonates, consisted of abstracts where all necessary details were unavailable, were case reports or duplications of other published studies, or dealt only with brain dead subjects.

DATA SYNTHESIS

For all studies (n = 44), positive likelihood ratio, positive predictive value, and sensitivity were 4.04, 71.2%, and 59.0%, respectively, for normal SEPs (predicting favorable outcome) and 11.41, 98.5%, and 46.2%, respectively, for bilaterally absent SEPs (predicting unfavorable outcome). Summary receiver operating characteristic curve analysis detected a cut-off criterion effect for only blinded studies of bilaterally absent SEPs. Twelve patients (12/777) were identified with bilaterally absent SEPs who had favorable outcomes. These false positives are typically pediatric patients or have suffered traumatic brain injuries. We suggest criteria for the use of bilaterally absent SEPs in the prediction of poor outcome, which include absence of focal lesions, subdural or extradural fluid collections, and no decompressive craniotomy in previous 48 hrs. Using these criteria the data suggest that the false-positive rate is <0.5% for bilaterally absent SEPs.

CONCLUSIONS

SEPs are powerful predictors of outcome, particularly poor outcome, if patients with focal lesions, subdural effusions, and those who have had recent decompressive craniotomies are excluded.

Can children recall their experiences of admission to an intensive care unit?

OBJECTIVE

To perform a pilot study to prospectively determine children's ability to recall events experienced during admission to a paediatric intensive care unit.

METHODS

Children's recall of the intensive care experience was evaluated, using telephone interview, at four to eight weeks and six to twelve months following discharge. Separate scores were assigned to reflect children's recall of general events and painful events. Recall was classified as either limited or extensive. Statistical analysis was performed to detect change in recall status over time and the association between the ability to recall and relevant admission variables (previous admission status, type of admission, frequency/intensity of painful procedures, length of stay and administration of analgesia/sedation).

RESULTS

In a sample of 50 children, recall of general events was extensive 4-8 weeks after discharge in 29 (58%) children and extensive in 26 (52%) children 6-12 months after discharge. Recall of painful events was extensive 4-8 weeks after discharge in 15 (30%) children and 14 (28%) children at 6-12 months after discharge. Thirteen (33.3%) of the 39 children who received analgesia/sedation had extensive recall of painful events at 4-8 weeks after discharge; 12 (30.8%) children had extensive recall at 6-12 months after discharge.

CONCLUSIONS

Children have the ability to recall many of their experiences related to admission to a paediatric intensive care unit and can continue to recall many of these experiences twelve months after discharge. Despite current methods for guiding titration of opiate infusions and intermittent administration of benzodiazepines, many children can recall painful experiences and general events encountered within the intensive care unit.

Device closure of an atrial septal defect following successful balloon valvuloplasty in a neonate with critical pulmonary valve stenosis and persistent cyanosis

Persistent cyanosis after successful balloon valvuloplasty for neonatal critical pulmonary valve stenosis is often related to poor right ventricular compliance and right-to-left shunting at the atrial level. A successful catheter closure of an atrial septal defect was performed with a dramatic increase in systemic oxygen saturation alleviating the need for a surgical systemic-to-pulmonary artery shunt.

Oxygenation is not improved by partial liquid high frequency ventilation using a high lung volume strategy. An experimental study

OBJECTIVE

To investigate the effect on oxygenation and lung damage of partial perfluorocarbon liquid high frequency oscillatory ventilation (PL-HFOV) versus high frequency oscillatory ventilation (HFOV) alone, in rabbits with acute lung injury, using high lung volume strategy HFOV.

METHODS

Twelve adult New Zealand white rabbits were initially ventilated with HFOV after anaesthesia, sedation and paralysis. After induction of lung injury with saline lavage, all animals received a single sigh breath of 30 cmH(2)O for 30 seconds. They were then allocated to receive either HFOV alone (n = 6) or PL-HFOV (n = 6). Arterial blood gases were taken pre- and post-lavage and then hourly for 5 hours. The oxygenation index (OI, in cmH(2)O/mmHg) was calculated using the formula: OI = (MAP x F(I)O(2) x 100) / PaO(2). The lungs were then removed for histological examination to score lung injury.

RESULTS

Two rabbits died in the PL-HFOV group and none in the HFOV group, p = 0.45 (Fisher's exact test). At one hour the oxygenation index (OI) was 4.5 in the HFOV group and 6.6 in the PL-HFOV group, p = 0.49 and the PaO(2) was 374 mmHg in the HFOV group and 311 mmHg in the PL-HFOV group, p = 0.39. Average OI over the first three hours was 3.6 in the HFOV group and 5.0 in the PL-HFOV group, p = 0.27 and the PaO(2) was 404 mmHg in the HFOV group and 337 mmHg in the PL-HFOV group, p = 0.12. The lung histology damage score was 2.33 in the HFOV group and 2.50 in the PL-HFOV group, p = 0.83.

CONCLUSIONS

In this model of acute lung injury, using a high volume HFOV strategy to optimise lung recruitment, PL-HFOV did not result in any further improvement in oxygenation when compared with HFOV alone. The question of safety with PL-HFOV remains.

Severe brain injury in children: long-term outcome and its prediction using somatosensory evoked potentials (SEPs)

OBJECTIVE

To evaluate the outcome of children 1 and 5 years after severe brain injury (Glasgow Coma Score < 8) using a functional measure [Glasgow Outcome Scale (GOS)] and a health status measure (the Torrance Health State (HUI:1)) and to determine the ability of somatosensory evoked potentials (SEPs) to predict these long-term outcomes.

DESIGN

Prospective study.

SETTING

A 16-bed paediatric intensive care unit in a tertiary children's hospital.

PATIENTS AND PARTICIPANTS

105 children with severe brain injury.

INTERVENTIONS

SEPs were recorded once in the first week after admission. Outcome was assessed 1 and 5 years after injury using the GOS and at 5 years after injury using HUI:1.

MEASUREMENTS AND RESULTS

At 5 years, using the GOS, 46 (43.8%) children had a good outcome, 10 (9.5%) were moderately disabled, 2 (1.9%) severely disabled, 3 (2.9%) vegetative and 44 (41.9%) had died. At 5 years, 17 of 40 (42.5%) survivors from 1 year had changed outcomes: 12 had improved, 3 had worsened and 2 had died. For a normal SEP, positive predictive power was 85.4%, sensitivity 62.5%, specificity 87.8%, negative predictive power 67.2% and the positive likelihood ratio was 5.1. For bilaterally absent responses, positive predictive power was 90.9%, sensitivity 61.2%, specificity 94.6%; negative predictive power 73.6% and the positive likelihood ratio was 11.4. Outcomes using HUI:1 were: 30 (28.6%) had a good quality of life, 21 (20.0%) had a moderate quality of life, 7 (6.7%) a poor quality, 44 died (41.9%) and 3 (2.9%) survived in a state deemed worse than death. For a normal SEP, positive predictive power was 85.4%, sensitivity 68.6%, specificity 88.9%, negative predictive power 75.0% and the positive likelihood ratio was 6.2. For bilaterally absent responses, positive predictive power was 93.9%, sensitivity 57.4%, specificity 96.1%, negative predictive power 68.1% and the positive likelihood ratio was 14.6.

CONCLUSION

The outcome for children with severe brain injury should be assessed 5 years after injury because important changes occur between 1 year and 5 years. Differences exist between outcomes assessed using the GOS and HUI:1 as they measure slightly different aspects of function. Consideration should therefore be given to using both measures. SEPs are excellent predictors of long-term outcome measured by either the GOS or the HUI:1.

Tracheobronchial malacia and stenosis in children in intensive care: bronchograms help to predict oucome

BACKGROUND

Severe tracheobronchial malacia and stenosis are important causes of morbidity and mortality in children in intensive care, but little is known about how best to diagnose these conditions or determine their prognosis.

METHODS

The records of all 62 children in whom one or both of these conditions had been diagnosed by contrast cinetracheobronchography in our intensive care unit in the period 1986-95 were studied.

RESULTS

Seventy four per cent of the 62 children had congenital heart disease; none was a preterm baby with airways disease associated with prolonged ventilation. Fifteen of the children had airway stenosis without malacia; three died because of the stenosis and two died from other causes. Twenty eight of the 47 children with malacia died; only eight children survived without developmental or respiratory handicap. All children needing ventilation for malacia for longer than 14 consecutive days died if their bronchogram showed moderate or severe malacia of either main bronchus (15 cases), or malacia of any severity of both bronchi (three additional cases); all children needing ventilation for malacia for longer than 21 consecutive days died if their bronchogram showed malacia of any severity of the trachea or a main bronchus (three additional cases). These findings were strongly associated with a fatal outcome (p<0.00005); they were present in 21 children (all of whom died) and absent in 26 (of whom seven died, six from non-respiratory causes). They had a positive predictive value for death of 100%, but the lower limit of the 95% confidence interval was 83.9% so up to 16% of patients meeting the criteria might survive.

CONCLUSION

In this series the findings on contrast cinetracheobronchography combined with the duration of ventilation provided a useful guide to the prognosis of children with tracheobronchomalacia. The information provided by bronchoscopy was less useful.

Recent advances in paediatric ventilation

BACKGROUND

To review the recent advances in ventilatory therapy for acute respiratory failure in children.

DATA SOURCES

Recent published peer-review articles on mechanical ventilation for acute respiratory failure in children.

SUMMARY OF REVIEW

Advances in conventional treatment for acute respiratory failure (e.g. mechanical ventilation) have not increased survival in children. However, recent therapies including high frequency ventilation, extracorporeal membrane oxygenation, nitric oxide and liquid ventilation have reported improved outcomes. The rationale and use of each are presented.

CONCLUSIONS

High frequency ventilation exists in three forms, although only high frequency oscillation appears to show any benefit in the management of acute respiratory failure refractory to conventional mechanical ventilation. Extracorporeal oxygenation has halved mortality in neonates with acute respiratory failure, and has been used successfully in non-neonate patients. Inhaled nitric oxide from 6 to 20 parts per million improves oxygenation in paediatric patients with acute respiratory failure and congenital heart disease (particularly in the presence of pulmonary arterial hypertension). Liquid ventilation or perfluorocarbon-associated gas exchange has also been used to treat acute respiratory failure in paediatric patients, with partial liquid ventilation particularly appearing to show promise.

Pulse oximetry for assessment of pulsus paradoxus: a clinical study in children

OBJECTIVE

To evaluate the relationship between intraarterial measured pulsus paradoxus (PP) and photoplethysmographic wave changes.

SETTING

Tertiary pediatric intensive care unit.

PATIENTS

62 nonintubated children with or without respiratory disorders.

DESIGN

Prospective, clinical study.

MEASUREMENTS AND RESULTS

Simultaneous paper recordings of photoplethysmographic wave, arterial blood pressure, breathing cycle and electrocardiogram. The respiratory dependent changes of the plethysmographic respiratory wave (delta pleth, mm) were defined as the difference between the highest value of the upper peak of the wave (in expiration) and the lowest value of the upper peak (in inspiration). In each patient, ten consecutive breaths were averaged for analysis. Five recordings could not be evaluated (movement artifacts). In 57 children (median age 2.4 years, range 7 days to 17 years), the photoplethysmographic fluctuations (delta pleth, mm) correlated with PP (mm Hg). r = 0.85; 95% confidence interval (CI), 0.76 to 0.91. The sensitivity to detect a PP of > 10 mmHg with a plethysmographic fluctuation of > 8 mm was 89% (95% CI, 77 to 100%) and the specificity was 90% (95% CI, 79 to 100%).

CONCLUSIONS

Pulse oximetry appears to be a rapid and easily performed, noninvasive method for the objective estimation of the degree of PP.

Early markers of major adverse events in children after cardiac operations

OBJECTIVES

The purpose of this study was to determine the physiologic variables that predict major adverse events in children in the intensive care unit after cardiac operations.

METHODS

A cohort observational study was conducted. At the time of admission to the intensive care unit and 4, 8, 12, and 24 hours later the following variables were recorded: mean arterial pressure, heart rate, cardiac index, oxygen delivery, mixed venous oxygen saturation, base deficit, blood lactate, gastric intramucosal pH, carbon dioxide difference (the difference between arterial carbon dioxide tension and gastric intraluminal carbon dioxide tension), and toe-core temperature gradient. Major adverse events were prospectively identified as cardiac arrest, need for emergency chest opening, development of multiple organ failure, and death.

RESULTS

Ninety children were included in the study; 12 had major adverse events and there were 4 deaths. Blood lactate level, mean arterial pressure, and duration of cardiopulmonary bypass were the only significant, independent predictors of major adverse events when measured at the time of admission to the intensive care unit. The odds ratio (95% confidence intervals) for major adverse events if a lactate level was greater than 4.5 mmol/L was 5.1 (1.2 to 21.1), for admission hypotension 2.3 (0.5 to 9.8), and for a cardiopulmonary bypass time greater than 150 minutes 13.7 (3.3 to 57.2). Four hours after admission lactate and carbon dioxide difference, and 8 hours after admission lactate and base deficit, were independently significant predictors. The odds ratios for major adverse events if the blood lactate level was greater than 4 mmol/L at 4 and 8 hours were 8.3 (1.8 to 38.4) and 9.3 (1.9 to 44.3), respectively. At no time in the first 24 hours were cardiac output, oxygen delivery, mixed venous oxygen saturation, toe-core temperature gradient, or heart rate significant predictors of major adverse events.

CONCLUSIONS

In the context of our current treatment strategies, the duration of cardiopulmonary bypass and blood lactate level, measured in the early postoperative period, were the best predictors of impending major adverse events.

Predictors of mortality and multiple organ failure in children with sepsis

OBJECTIVES

To assess the markers of perfusion which best discriminate survivors from non-survivors of childhood sepsis and to compare the information derived from gastric tonometry with conventionally measured haemodynamic and laboratory parameters.

DESIGN

Prospective clinical study of children with sepsis syndrome or septic shock.

SETTING

Paediatric intensive care unit in a tertiary referral centre.

PATIENTS

31 children with sepsis syndrome or septic shock.

INTERVENTIONS

A tonometer was passed into the stomach via the orogastric route.

MEASUREMENTS AND MAIN RESULTS

The following data were recorded at admission, 12, 24 and 48 h: heart rate, mean arterial pressure, arterial pH, base deficit, arterial lactate, gastric intramucosal pH (pHi) and DCO2 (intramucosal carbon dioxide tension minus arterial partial pressure of carbon dioxide). The principal outcome measure was. The secondary outcome measure was the number of organ systems failing at 48 h after admission. There were 10 deaths and 21 survivors. No variable discriminated survival from death at presentation. Blood lactate level was the earliest discriminator of survival. Using univariate logistic regression, lactate discriminated survivors from those who died at 12 and 24 h after admission, but not at 48 h (p = 0.049, 0.044 and 0.062, respectively). The area under the receiver operating characteristic (ROC) curve for lactate was 0.81, 0.88 and 0.89 at 12, 24 and 48 h, respectively. At 12 h after admission, a blood lactate level > 3 mmol/l had a positive predictive value for death of 56% and a lactate level of 3 mmol/l or less had a positive predictive value for survival of 84%. At 24 h a lactate level > 3 mmol/l had a positive predictive value for death of 71% and a level of 3 mmol/l or less had a positive predictive value for survival of 86%. No other variable identified non-survivors from survivors at 12 h. Gastric tonometry could only be done on 19 of the 31 children, of whom 8 died and 11 survived. In these 19 children, DCO2 measured at 24 h, but not at 12 or 48 h, distinguished those who died from those who survived (p = 0.045 and p = 0.20, respectively). The area under the ROC curve for DCO2 measured at 24 h as a predictor of survival was 0.71. Neither the absolute value of pHi nor the trend of change in pHi at any time in the first 48 h identified survivors in this series. The mean arterial pressure distinguished survivors from non-survivors at 24 and 48 h (area under ROC curve = 0.80 and 0.78, respectively). The base deficit and heart rate did not identify non-survivors from survivors at any time in the first 48 h.

CONCLUSIONS

Blood lactate level was the earliest predictor of outcome in children with sepsis. In this group of patients, gastric tonometry added little to the clinical information that could be derived more simply by other means.

Extracorporeal support for intractable cardiorespiratory failure due to meningococcal disease

BACKGROUND

Meningococcal disease is still associated with considerable mortality, despite the use of early antibiotics and management in specialised intensive care units, due principally to early refractory myocardial depression and hypotension as well as severe acute respiratory distress syndrome. Extracorporeal membrane oxygenation (ECMO) is a complex technology that uses a modified "heart-lung" machine to provide temporary cardiac and respiratory support. We reviewed the UK and Australian experience of the use of ECMO in patients with refractory cardiorespiratory failure due to meningococcal disease.

METHODS

The records from all 12 known patients supported with ECMO for meningococcal disease in the UK and Australia since 1989 were reviewed.

FINDINGS

12 patients (aged 4 months to 18 years, median 26 months) with meningococcal disease received ECMO over 8 years. In seven patients, ECMO was required early for cardiac support for intractable shock within 36 h of admission to intensive care. In the other five patients, ECMO was indicated for respiratory failure due to severe adult respiratory distress syndrome, which tended to occur later in the disease. The paediatric risk of mortality score ranged from 13 to 40 (median 29, median predicted risk of mortality 72%). Six of the 12 patients required cardiopulmonary resuscitation before ECMO and the other six were deteriorating despite maximal conventional therapy. Overall, eight of the 12 patients survived, with six leading functionally normal lives at a median of 1 year (range 4 months to 4 years) of follow-up.

INTERPRETATION

ECMO might be considered to support patients with intractable cardiorespiratory failure due to meningococcal disease who are not responding to conventional treatment.

Extreme sodium derangement in a paediatric inpatient population

OBJECTIVE

To determine the aetiology, symptoms and outcome of extreme sodium derangement in a paediatric inpatient population.

METHODOLOGY

A retrospective study of children with extreme disturbance of their plasma sodium (> or = 165 mmol/L or < or = 115 mmol/L) admitted to a tertiary referral centre during a 72-month period.

RESULTS

Twenty-seven cases of hypernatraemia and 21 of hyponatraemia were reviewed. Sodium disturbance developed after hospital admission in 27/57 cases (57%). Gastroenteritis was the most common cause of hypernatraemia (8/27; 30%), four of 27 (15%) had iatrogenic hypernatraemia. Water overload accounted for 8/21 (38%) cases of hyponatraemia. Neurologic symptoms occurred in 19/24 (79%) with hypernatraemia and in 11/19 (58%) with hyponatraemia. Ten (37%) with hypernatraemia and four (19%) with hyponatraemia died. A deterioration in functional status was seen in two patients with hypernatraemia. There was no apparent deterioration in the survivors with hyponatraemia.

CONCLUSION

Extreme sodium disturbance often develops after admission to hospital and is caused by a variety of diseases and interventions. Neurologic symptoms are common and the mortality rate is high. The outcome in survivors is survivors is most likely to be dependent on the underlying disease process.

The DCO2 measured by gastric tonometry predicts survival in children receiving extracorporeal life support. Comparison with other hemodynamic and biochemical information. Royal Children's Hospital ECMO Nursing Team

STUDY OBJECTIVE

To assess the role of gastric tonometry in monitoring children receiving extracorporeal life support (ECLS) and to determine if DCO2 or pHi in the weaning phase of ECLS predicts survival.

DESIGN

A prospective study of consecutive patients treated with ECLS.

SETTING

A tertiary pediatric ICU that is the ECLS referral center for Australia.

PATIENTS

Twenty consecutive children receiving ECLS for cardiovascular or respiratory failure.

INTERVENTIONS

All children were monitored throughout their ECLS course using a tonometer inserted into the stomach via the orogastric route. The PCO2 in the tonometer balloon was measured every 4 to 6 h and the pHi was calculated using the Henderson-Hasselbalch equation. The DCO2, which is the difference between PCO2 in tonometer saline solution and arterial blood, was calculated. We compared the ability of pHi, DCO2, heart rate, mean arterial pressure, arterial pH, base deficit, and blood lactate to predict death or survival during the weaning phase. Measurements were taken on the lowest level of support, which for veno-arterial extracorporeal membrane oxygenation and ventricular assist device was defined as the lowest ECLS pump flows, and on veno-venous extracorporeal membrane oxygenation was defined as the time of lowest ECLS gas flow. Predictive power was assessed using the receivor operating characteristic (ROC) analysis on the data collected at these times.

RESULTS

In the weaning phase of ECLS, the pHi was significantly lower in children who died (pHi = 7.21; 95% confidence intervals, 7.14 to 7.28) than in those who survived (pHi = 7.38; 95% confidence intervals, 7.28 to 7.47). The DCO2 was significantly higher in children who died (23.6 mm Hg; 95% confidence intervals, 14.3 to 33.1) compared with survivors (4.7 mm Hg; 95% confidence intervals, -0.78 to 10.1). The area under the ROC curve was 0.95 for DCO2 (and 0.88 for pHi). pHi and DCO2 predicted survival better than base deficit (area under ROC curve, 0.82), blood lactate level (0.29), arterial pH (0.65), heart rate (0.62), and mean arterial pressure (0.74).

CONCLUSIONS

DCO2 is a clinically meaningful measurement in children receiving ECLS. A high DCO2 was a good predictor of death in this series. Gastric tonometry may provide a useful measure of the adequacy of regional perfusion and oxygenation in this group of patients.

The outcome of children admitted to intensive care with meningococcal septicaemia

OBJECTIVE

To review our experience of children with meningococcal septicaemia, and to validate, in our group, severity scores used in different populations to predict outcome.

DESIGN

Retrospective review of case notes and charts.

PATIENTS

A total of 35 children were admitted to the paediatric intensive care unit (ICU) in the Royal Children's Hospital (RCH) in the 8 years between January 1985 and December 1992 with proven meningococcal septicaemia.

RESULTS

Ages ranged from 4 months to 16 years, with a median age of 20 months. The median meningococcal score was 4 and the median PRISM score was 20, with scores above these being significantly associated with death (P < 0.0001). Thirty-two children (91%) received infusions of colloid for hypovolaemia and twenty-nine (83%) received one or more inotropic drugs. Twenty-one children (60%) required mechanical ventilation for a median of 16.5 h (range 7-574). Seven children (20%) underwent plasmapheresis. Six children (17%) underwent haemofiltration and two (6%), peritoneal dialysis. One patient received extracorporeal membrane oxygenation (ECMO) because of circulatory failure. Twenty-one children (60%) developed disseminated intravascular coagulation, renal failure and/or skin or limb necrosis. The overall survival was 66%, and all survivors are functionally normal.

CONCLUSION

The mortality from the disease remains at 34% despite the technological advances in intensive care. The PRISM and meningococcal scores are useful in predicting outcome. Novel methods of treatment (e.g., plasmapheresis or ECMO) may be valuable.

Inferior vena cava pressure as an estimate of central venous pressure

OBJECTIVE

To determine whether pressure in the inferior vena cava (IVC) is similar to central venous pressure.

METHODOLOGY

Prospective measurement of both central venous pressure (CVP) and inferior vena cava pressure (IVCP) in the same child; each child had to have both catheters in situ. Two measurements of each pressure in reverse order (IVCP then CVP, and CVP then IVCP) were done and the mean of each was recorded. Comparison of the pressures was performed using the method of Bland and Altman.

RESULTS

Thirty-nine children had pressures recorded. The CVP ranged from 3 to 17 mmHg. In 22 of 39 measurements IVCP was equal to CVP; in 33 of 39 measurements IVCP was different from CVP by 1 mm or less and in 37 of 39 measurements IVCP was different from CVP by 2 mm or less. The mean difference between IVCP and CVP was +0.33 mmHg, the 95% confidence interval was 2.26 to +2.93 mmHg.

CONCLUSION

Measurement of IVCP is a good approximation to CVP and can be routinely used in clinical care of children who do not have raised intra-abdominal pressure.

An evaluation of changes in composition and contamination of salvaged blood from the cardiopulmonary bypass circuit of pediatric patients

OBJECTIVE

To review changes that occur during an 18-hour period in composition and bacterial contamination of blood salvaged from the cardiopulmonary bypass (CPB) circuit of pediatric patients.

DESIGN

Prospective, blinded study.

SETTING

Pediatric tertiary multidisciplinary intensive care unit.

PATIENTS

One hundred and one children who underwent CPB.

OUTCOME MEASURES

The degree of bacterial contamination and biochemical and hematologic alterations of blood salvaged from the CPB and any increased blood loss associated with reinfusion of this blood.

INTERVENTION

The salvaged blood from the CPB circuit was collected into 1 L blood transfer packs after CPB. This blood was then stored at room temperature for 18 hours. Sampling occurred immediately after CPB and at 6 and 18 hours for biochemic and hematologic assay and for the detection of bacterial organisms. The amount of chest drainage loss was assessed in the first 18 hours after bypass. The type and amount of intravenous fluid infused also was recorded.

RESULTS

Bacterial contamination occurred in three samples (two at 6 hours and in one of the preceding at 18 hours) of the 101 units of salvaged blood. All three positive cultures grew a coagulase-negative staphylococcus. Sodium and potassium remained within normal physiologic values. The glucose values declined from 15.8 to 13.4 mmol/L, and the hemoglobin values increased from 0.4 to 0.5 gm/dl. The reinfusion of the salvaged blood (and any other blood or blood products) to 31 of the 101 patients averaged 14.2 ml/kg/24 hr, with a mean chest drainage loss of 4.9 ml/kg/24 hr. The remaining 70 patients received 12.5 ml/kg/hr of either plasma expanders or blood, with a mean chest drainage loss of 6.0 ml/kg/24 hr.

CONCLUSIONS

The results of this study demonstrate minimal chemical deterioration and limited microbiologic contamination in blood that was salvaged from the CPB circuit and stored at room temperature for an 18-hour period. No increase in postoperative bleeding was noted from the use of this blood. These results suggest it may be safe to reinfuse salvaged blood after CPB in pediatric patients for up to 18 hours; however, a prospective clinical trial is needed to validate these findings.

Somatosensory evoked potentials for prediction of outcome in acute severe brain injury

The purpose of this study was to evaluate prospectively short-latency somatosensory evoked potentials (SEPs) as a predictor of outcome in acute, severe brain injury, and to compare this with the predictive power of the motor component of the Glasgow Coma Scale score and computed tomographic scan. Outcome was measured with the Glasgow Outcome Scale at a minimum of 6 months after injury. We studied 109 patients (aged 0.1 to 16.8 years) with SEPs within 4 days of the onset of coma. Four patients had absent SEPs and a favorable outcome by the Glasgow Outcome Scale (full recovery or moderate disability); two of these patients had meningitis with bilateral subdural effusions, one had a midbrain hemorrhage, and one had a decompressive craniectomy for uncontrolled intracranial hypertension. Normal SEPs had a positive predictive value for favorable outcome of 93% (95% confidence interval (CI), 77% to 99%), and absent SEPs had a positive predictive value for unfavorable outcome by the Glasgow Outcome Scale (severe disability, survival in a persistent vegetative state, or death) of 92% (95% CI, 80% to 98%). If the above identifiable clinical situations in which a physical barrier existed to impede cutaneous reception of the electrical impulse were excluded, the positive predictive value of absent SEPs for poor outcome reached 100% (95% CI, 92% to 100%). An absent motor response to painful stimulus also had 100% positive predictive value (95% CI, 84% to 100%) for unfavorable outcome; however, 23% of patients could not be evaluated because of the effects of muscle relaxants or sedatives. In patients with traumatic brain injury, results of computed tomography did not reliably predict outcome. Of the 59 patients with unfavorable outcome, 76% could be identified with SEPs compared with 36% with examination of motor function. We suggest that SEPs be performed in children with acute severe brain injury because they add an important tool to the physician's prognostic armamentarium. We conclude that in the absence of the above mentioned identifiable clinical situations, absent SEPs predict 100% unfavorable outcome, and this finding may warrant consideration of withdrawal of treatment in children with brain injuries.

Predictors of survival for infants with congenital diaphragmatic hernia

Over the past decade, the survival rate of infants with congenital diaphragmatic hernia (CDH) treated in the intensive care unit of the Royal Children's Hospital, Melbourne, has remained unchanged at 56% +/- 6%. Newer forms of treatment, such as extracorporeal membrane oxygenation (ECMO), high-frequency oscillation, and surfactant and nitric oxide therapy, are now available. The exact role of these therapies in the management of infants with CDH has not been determined. This study examines five clinical parameters derived from an infant's best preoperative ventilatory and blood gas data in the first 24 hours of life. One hundred twenty-five CDH infants were admitted to the intensive care unit between January 1, 1981 and December 31, 1991. Criteria for inclusion in the study were (1) CDH diagnosed within 6 hours of delivery, (2) ventilation before repair, and (3) no associated lethal congenital abnormality. Of the 90 cases studied in detail, there were 38 deaths (42% mortality rate). All five parameters were analyzed by receiver operating curve analysis to determine the optimum value of each parameter in predicting survival. An oxygenation index (MAP x FIO2/PaO2) of less than 0.08 predicted a 94% chance of survival, with a sensitivity of 96% and a specificity of 95%. Similarly, a modified ventilation index (PIP x RR x CO2/1,000) of less than 40 predicted a 91% chance of survival, with a sensitivity of 94% and a specificity of 86%. By stratifying each criterion according to outcome, three groups of infants were identified according to their response to conventional therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Extracorporeal membrane oxygenation for refractory septic shock in children

OBJECTIVE

To review demographic data and outcome of children who received extracorporeal membrane oxygenation (ECMO) for refractory septic shock.

METHOD

Review of medical charts of nine children receiving ECMO for culture-proven refractory septic shock treated in a multidisciplinary pediatric intensive care unit.

RESULTS

Median age was 12 years and median weight was 45 kg. Median inotrope requirements (micrograms/kg per minute) before ECMO were dopamine, 15; dobutamine, 12.5; epinephrine, 4; and norepinephrine, 3.5. Four children received two inotropes concurrently, and five received three or more. All nine patients had severe respiratory failure; eight had evidence of other organ system dysfunction, with six having five or more organ system dysfunctions. Median PRISM score was 27. Median duration of ECMO was 137 hours. Within 24 hours of starting ECMO, 7 of 9 children had all inotropes stopped. Four patients died and five survived, all of whom are leading normal lives.

CONCLUSION

In this small group of children with probably fatal septic shock, ECMO was successfully supported the circulation and 5 of the 9 children survived. We suggest that septic shock should not be considered a contraindication to ECMO.