Blood Lost: A Retrospective Review of Blood Wastage from a Massive Transfusion Protocol in a Tertiary Paediatric Hospital

BACKGROUND

The paediatric massive transfusion protocol (MTP) is activated in the paediatric population for both trauma and non-trauma related indications. While it helps to improve the efficiency and efficacy of the delivery of blood products, it can also result in increased wastage. We aimed to evaluate the wastage rates from our paediatric MTP activations from 2013 to 2018.

METHOD

As part of an audit, we retrospectively reviewed the records of the paediatric patients who had MTP activations. We collected the following data: reason for MTP activation, weight of patient, number of cycles of MTP required, blood products used, blood products wasted, deviation from our institution's recommended MTP blood product ratio, and reason for wastage.

RESULT

We had 26 paediatric MTP activations within the audit period. There was an overall wastage rate of 1.5%, with wastage occurring in 3 out of 26 patients. The reason for all wastage was demise of the patient. Most patients' transfusion ratios deviated from our institution's MTP protocol.

CONCLUSION

Our wastage rates are low likely because of clear MTP activation guidelines and a flexible MTP workflow.

Home-Initiated-Programme-to-Prepare-for-Operation: evaluating the effect of an animation video on peri-operative anxiety in children: A randomised controlled trial

BACKGROUND

Hospital admissions and surgical operations commonly trigger anxiety in young children. Despite employing numerous support measures in our hospital, such as a pre-operative play room, the encouragement of parental companionship during induction of anaesthesia and distraction therapy, allaying the anxiety of our young surgical patients remains a challenge.

OBJECTIVES

To evaluate the effectiveness of a Home-Initiated-Programme-to-Prepare-for-Operation (HIPPO) on emotional manifestation and anxiety in children undergoing surgery.

DESIGN, SETTING AND PATIENTS

One hundred and thirty children were randomly assigned to either control or intervention group between February 2018 and April 2019 in a tertiary paediatric hospital in Singapore.

INTERVENTION

In addition to our standard pre-operative workflow, the intervention group received an additional home preparation kit consisting of an animated video on preoperative preparation and age-specific preoperative preparation activity sheets.

MAIN OUTCOME MEASURES

The primary outcome was the Children's Emotional Manifestation Scale score to evaluate behaviour and emotion in the children before and during induction of anaesthesia. Secondary outcomes evaluated anxiety levels in parents and children, the child's behaviour and degree of co-operation using the State-Trait Anxiety Inventory scores, State-Trait Anxiety Inventory Children scores, the Induction Compliance Checklist scores, the Visual Analogue Scale scores for anxiety and the feedback questionnaire.

RESULTS

The difference between the Children's Emotional Manifestation Scale score in control and intervention groups was not statistically significant. A promising difference was however observed in one of the secondary outcomes where the state-State-Trait Anxiety Inventory Children scores of 7 to 10-year olds in the intervention group almost reached significance; P = 0.067.

CONCLUSION

Despite being a child-friendly, easily accessible and affordable tool for patient education, HIPPO did not reduce anxiety experienced by children in the pre-operative waiting area or during induction of anaesthesia.

TRIAL REGISTRATION

ClinicalTrials.gov, identifier: NCT04271553.

Cost of inpatient rehabilitation for children with moderate to severe traumatic brain injury

AIM

To evaluate the cost of inpatient rehabilitation for children with moderate to severe traumatic brain injury (TBI). Secondary aim was to identify factors associated with high inpatient rehabilitation cost.

METHOD

Retrospective review of a tertiary hospital's trauma registry was performed from 2011-2017. All patients aged 16 years or younger who sustained TBI with Glasgow Coma Scale ≤13 were included. Data on patient demographics, mechanism and severity of injury, hospital duration and inpatient rehabilitation cost were collected. We performed a regression analysis to identify factors associated with high rehabilitation cost.

RESULTS

There were a total of 51 patients. The median duration of inpatient rehabilitation was 13.5 days (interquartile range [IQR] 4-35), amounting to a median cost of SGD8,361 (IQR 3,543-25,232). Daily ward costs contributed the most to total inpatient rehabilitation cost. Those with severe TBI had longer duration of inpatient rehabilitation that resulted in higher cost of inpatient rehabilitation. Presence of polytrauma, medical complications, post-traumatic amnesia and TBI post-non-accidental injury (NAI) were associated with higher cost of inpatient rehabilitation.

CONCLUSION

The cost of inpatient rehabilitation for paediatric patients post-TBI is significant in Singapore. Patients with TBI secondary to NAI had significantly higher cost of inpatient rehabilitation. Ways to reduce duration of hospitalisation post-TBI and early step-down care or outpatient rehabilitation should be explored to reduce cost.

Epidemiology of Pedestrian-Motor Vehicle Fatalities and Injuries, 2006-2015

INTRODUCTION

Pedestrian road safety remains a public health priority. The objective of this study is to describe trends in fatalities and injuries after pedestrian-motor vehicle collisions in the U.S. and identify associated risk factors for pedestrian fatalities.

METHODS

This is a cross-sectional study of U.S. pedestrian-motor vehicle collisions from 2006 to 2015 (performed in 2017). Pedestrian fatality and injury data were obtained from the National Highway Traffic Safety Administration's Fatality Analysis Reporting System and National Automotive Sampling System General Estimates System. Frequencies of fatalities, injuries, and associated characteristics were calculated. Multivariable logistic regression was performed for risk of fatality, controlling for demographic and crash-related factors.

RESULTS

There were 47,789 pedestrian fatalities and 674,414 injuries during the 10-year study period. Fatality rates were highest among the elderly aged 85 years and older (2.95/100,000 population), whereas injury rates were highest for those aged 15-19 years (35.23/100,000 population). Predictors associated with increased risk for death include the following: male sex (AOR=1.36, 95% CI=1.15, 1.62), age ≥65 years (AOR=3.44, 95% CI=2.62, 4.50), alcohol involvement (AOR=2.63, 95% CI=1.88, 3.67), collisions after midnight (AOR=5.21, 95% CI=3.20, 8.49), at non-intersections (AOR=2.76, 95% CI=2.21, 3.45), and involving trucks (AOR=2.15, 95% CI=1.16, 3.97) and buses (AOR=5.82, 95% CI=3.67, 9.21).

CONCLUSIONS

Potentially modifiable factors are associated with increased risk of death after pedestrian-motor vehicle collisions. Interventions including elder-friendly intersections and increasing visibility of pedestrians may aid in decreasing pedestrian injuries and deaths.

Development of an isotopic stream index connecting physiographic characteristics of montane catchments

This study is to develop an isotopic catchment-effect index (CEI) connecting the physiographic characteristics of stream catchments. A CEI, describing the extent of difference in stable water isotopic compositions (δ values) between stream water and local precipitation at any given sampling site, can help in judging whether water resource management should be focused on upstream regions of streams or local hydrology issues. To establish the isotopic CEI, this study measured δ values of stream water and derived δ¹⁸ O of local precipitation based on regional isotopic altitude gradient at montane catchments of various sizes. Results indicate that the CEI is strongly related to catchment physiographic characteristics, such as length of main stream, mean area, mean elevation, perimeter, and slope. These characteristics are considered important indices of streamflow. Based on mathematical regression modeling describing the relationships between CEI and respective physiographic factors, CEI values can predict respective physiographic factors and vice versa. Moreover, according to the multiple equations derived in this study, catchments of larger size and steeper slope give elevated CEI values while greater stream length reduces the CEI's value. A greater CEI value indicates that local stream water is principally sourced from upstream reaches rather than contributions from local precipitation. In addition, CEI values are greater in winter than in summer resulting from monsoon effect. Consequently, this study establishes CEI as a useful descriptor of the physiographic characteristics of catchments.

Resection of an intra-operative ruptured hepatocellular carcinoma with continuous pringle maneuver and in situ hypothermic perfusion through the inferior mesenteric vein: a case report

Intra-operative tumor rupture is a serious complication during resection of large hepatocellular carcinoma (HCC) leading to more blood loss. We report our experience in applying continuous Pringle maneuver with in situ hypothermic perfusion via inferior mesenteric vein catheterization to the portal vein of the remnant liver for resection during an extended left lobectomy of a large HCC which ruptured intraoperatively. Using this method, we successfully managed the patient without any further morbidity. This technique provides easier accessibility of in situ perfusion, decreases operative blood loss and prevents warm ischemic injury to the remnant liver during parenchymal transection. This method could be effective for the resection of large ruptured HCC.

Intra-operative management of low portal vein flow in pediatric living donor liver transplantation

For pediatric living donor liver transplantation, portal vein complications cause significant morbidity and graft failure. Routine intra-operative Doppler ultrasound is performed after graft reperfusion to evaluate the flow of portal vein. This retrospective study reviewed 65 children who had undergone living donor liver transplantation. Seven patients were detected with suboptimal portal vein flow velocity following vascular reconstruction and abdominal closure. They underwent immediate on-table interventions to improve the portal vein flow. Both surgical and endovascular modalities were employed, namely, graft re-positioning, collateral shunt ligation, thrombectomy, revision of anastomosis, inferior mesenteric vein cannulation, and endovascular stenting. The ultrasonographic follow-up assessment for all seven patients demonstrated patent portal vein and satisfactory flow. We reviewed our experience on the different modalities and proposed an approach for our future intra-operative management to improve portal vein flow at the time of liver transplantation.

Persistent sterile pyuria in children? Don't forget tuberculosis!

Genitourinary tuberculosis (GUTB) is exceptionally uncommon among the local paediatric population. A 10-year-old Chinese girl with no risk factors for tuberculosis presented with recurrent sterile pyuria. Despite extensive renal investigations, no apparent cause could be ascertained for her obstructed left drainage system. The diagnosis was eventually confirmed with urine acid-fast bacilli culture, after a computed tomography scan suggested possible renal tuberculosis. Left nephroureterectomy had to be performed owing to deteriorating left kidney function. This report discusses the importance of considering tuberculosis when assessing a local paediatric patient with an atypical urinary tract infection. Early diagnosis of renal tuberculosis can prevent the sequelae of GUTB, including renal impairment.

Kinetic and pharmacological properties of GABA(A) receptors in single thalamic neurons and GABA(A) subunit expression

Synaptic inhibition in the thalamus plays critical roles in sensory processing and thalamocortical rhythm generation. To determine kinetic, pharmacological, and structural properties of thalamic gamma-aminobutyric acid type A (GABA(A)) receptors, we used patch-clamp techniques and single-cell reverse transcriptase polymerase chain reaction (RT-PCR) in neurons from two principal rat thalamic nuclei-the reticular nucleus (nRt) and the ventrobasal (VB) complex. Single-channel recordings identified GABA(A) channels with densities threefold higher in VB than nRt neurons, and with mean open time fourfold longer for nRt than VB [14.6 +/- 2.5 vs. 3.8 +/- 0.7 (SE) ms, respectively]. GABA(A) receptors in nRt and VB cells were pharmacologically distinct. Zn(2+) (100 microM) reduced GABA(A) channel activity in VB and nRt by 84 and 24%, respectively. Clonazepam (100 nM) increased inhibitory postsynaptic current (IPSC) decay time constants in nRt (from 44.3 to 77.9 ms, P < 0.01) but not in VB. Single-cell RT-PCR revealed subunit heterogeneity between nRt and VB cells. VB neurons expressed alpha1-alpha3, alpha5, beta1-3, gamma2-3, and delta, while nRt cells expressed alpha3, alpha5, gamma2-3, and delta. Both cell types expressed more subunits than needed for a single receptor type, suggesting the possibility of GABA(A) receptor heterogeneity within individual thalamic neurons. beta subunits were not detected in nRt cells, which is consistent with very low levels reported in previous in situ hybridization studies but inconsistent with the expected dependence of functional GABA(A) receptors on beta subunits. Different single-channel open times likely underlie distinct IPSC decay time constants in VB and nRt cells. While we can make no conclusion regarding beta subunits, our findings do support alpha subunits, possibly alpha1 versus alpha3, as structural determinants of channel deactivation kinetics and clonazepam sensitivity. As the gamma2 and delta subunits previously implicated in Zn(2+) sensitivity are both expressed in each cell type, the observed differential Zn(2+) actions at VB versus nRt GABA(A) receptors may involve other subunit differences.

An orchestrated gene expression component of neuronal programmed cell death revealed by cDNA array analysis

Programmed cell death (PCD) during neuronal development and disease has been shown to require de novo RNA synthesis. However, the time course and regulation of target genes is poorly understood. By using a brain-biased array of over 7,500 cDNAs, we profiled this gene expression component of PCD in cerebellar granule neurons challenged separately by potassium withdrawal, combined potassium and serum withdrawal, and kainic acid administration. We found that hundreds of genes were significantly regulated in discreet waves including known genes whose protein products are involved in PCD. A restricted set of genes was regulated by all models, providing evidence that signals inducing PCD can regulate large assemblages of genes (of which a restricted subset may be shared in multiple pathways).

Functional implications of the subunit composition of neuronal CaM kinase II

The assembly of 6-12 subunits of Ca(2+)/calmodulin-dependent kinase II (CaM kinase II) into holoenzymes is an important structural feature of the enzyme and its postulated role as a molecular detector of Ca(2+) oscillations. Using single cell reverse transcriptase-polymerase chain reaction, we show that alpha- and beta-CaM kinase II mRNAs are simultaneously present in the majority of hippocampal neurons examined and that co-assembly of their protein products into heteromers is therefore possible. The subunit composition of CaM kinase II holoenzymes was analyzed by immunoprecipitation with subunit-specific monoclonal antibodies. Rat forebrain CaM kinase II consists of heteromers composed of alpha and beta subunits at a ratio of 2:1 and homomers composed of only alpha subunits. We examined the functional effect of the heteromeric assembly by analyzing the calmodulin dependence of autophosphorylation. Recombinant homomers of alpha- or beta-CaM kinase II, as well as of alternatively spliced beta isoforms, have distinct calmodulin dependences for autophosphorylation based on differences in their calmodulin affinities. Half-maximal autophosphorylation of alpha is achieved at 130 nM calmodulin, while that for beta occurs at 15 nM calmodulin. In CaM kinase II isolated from rat forebrain, however, the calmodulin dependence for autophosphorylation of the beta subunits is shifted toward that of alpha homomers. This suggests that Thr(287) in beta subunits is phosphorylated by alpha subunits present in the same holoenzyme. Once autophosphorylated, beta-CaM kinase II traps calmodulin by reducing the rate of calmodulin dissociation.

Detection of gene expression in single neurons by patch-clamp and single-cell reverse transcriptase polymerase chain reaction

Detection and quantitation of gene expression in single cells is especially important in the central nervous system where, at the cellular level, the synapse can be considered the single functional unit. For example, the consolidation of long-term memories may be mediated by persistent changes in the strength of synaptic transmission at individual synapses. In order to investigate the requirement for de novo RNA synthesis during long-term potentiation in individual neurons, we have combined single-cell electrophysiology with single-cell gene-expression methodology. Described are methods combining whole-cell patch-clamp and single-cell RT-PCR for the detection of a single mRNA species for nitric oxide synthase, or, through a multiplex strategy, for the simultaneous detection of several mRNAs including heme oxygenase 2, protein phosphatase inhibitor 1 protein, and several isoforms of the calcium/calmodulin dependent protein kinase II.

Nitric oxide synthase expression in single hippocampal neurons

The presence of nitric oxide synthase (NOS) in CA1 pyramidal cells of the rat hippocampus was demonstrated by single-cell PCR. NOS-specific primers were used to amplify mRNA isolated from single hippocampal neurons. The sequence of the major amplification-product obtained was identical to that of the constitutively expressed brain-isoform of NOS. These results confirm immunocytochemical data that NOS is present in CA1, and, therefore, nitric oxide could function as a retrograde messenger in long-term potentiation.

Mutational analysis of a C-dependent late promoter of bacteriophage Mu

Late transcription of bacteriophage Mu initiates at four promoters, P(lys), PI, PP and Pmom, and requires the Mu C protein and the host RNA polymerase. Promoter-containing DNA fragments extending approximately 200 bp upstream and downstream of the 5' starts of the lys, I and P transcripts were cloned into a multicopy lacZ-expression plasmid. Promoter activity, assayed by beta-galactosidase expression, was determined under two different conditions: (1) with C provided from a compatible plasmid in the absence of other Mu factors and (2) with C provided from an induced Mu prophage. beta-galactosidase activities were greatest for P(lys), intermediate for PI, and lowest for PP. Similar analysis of plasmids containing nested sets of deletions removing 5' or 3' sequences of P(lys) demonstrated that a 68-bp region was sufficient for full activity. Point mutations were generated within the 68-bp region by mutagenic oligonucleotide-directed PCR (Mod-PCR). Properties of the lys promoter mutants indicated that, in addition to the -10 region, a 19-bp region from -52 to -34 containing the C footprint is required for C-dependent promoter activity.

Mutagenic oligonucleotide-directed PCR amplification (Mod-PCR): an efficient method for generating random base substitution mutations in a DNA sequence element

Saturation mutagenesis is one approach for determining the contributions of individual base pairs to the structure and function of defined DNA sequence elements. In this paper, we describe a novel method for saturation mutagenesis involving PCR amplification with degenerate synthetic oligonucleotides as primers. The degeneracy is confined to a specific target within the primer by mixing a low percentage of the three non-wild type (non-WT) nucleotide precursors with WT at specific positions during primer synthesis. PCR amplification of WT template DNA with the degenerate primer and an opposing WT primer, followed by subsequent cloning using restriction sites designed into the primers, results in recovery of a population of randomly mutated products. Since primers with multiple mutations hybridize less efficiently to WT template DNA during PCR amplification, the recovery of mutants with multiple base changes is greatly reduced. The efficient generation of random point mutations with this method allows the construction of separate mutant populations, each mutagenized over a different portion of the DNA sequence element. If a phenotypic assay is available, these populations can be screened directly to define those regions within the element that are important for activity. Only those populations containing mutations in the important regions require further characterization by DNA sequence analysis.