Perioperative management of pediatric patients undergoing juvenile angiofibroma resection. A case series and educational review highlighting patient blood management.

BACKGROUND: Juvenile nasopharyngeal angiofibromas are one of the most enigmatic, bloody tumors encountered by otorhinolarygnologists, head and neck surgeons, neurosurgeons, and anesthesiologists. Juvenile nasopharyngeal angiofibromas are rare, benign, highly vascular tumors with a propensity towards aggressive local invasion. Surgery, open or endoscopic, to remove the growth is the primary treatment of choice for Juvenile nasopharyngeal angiofibromas. Historically, surgical resection was associated with massive, rapid blood loss, traditionally managed by blood product transfusion and deliberate hypotension. Preventative management employing multimodal blood conservation strategies should be an essential standard of perioperative care for patients with Juvenile nasopharyngeal angiofibromas. METHODS: We describe a contemporary and comprehensive approach in the management of patients with high grade Juvenile nasopharyngeal angiofibromas. This includes surgical strategies such as preemptive external carotid artery embolization, endoscopic surgical approach, and staged operations, as well as anesthetic strategies including antifibrinolytic therapy and acute normovolemic hemodilution. These surgeries, once synonymous with massive transfusion, may potentially be performed without allogeneic blood transfusion, or deliberate hypotension. AIMS: Using a case series, the authors introduce a contemporary approach to multimodal, multidisciplinary blood conservation strategies for Juvenile nasopharyngeal angiofibromas surgery. RESULTS: Here in the authors report on an updated contemporary perioperative clinical approach to patients with Juvenile nasopharyngeal angiofibromas. From an anesthetic perspective, we describe the successful use of normal hemodynamic goals, restrictive transfusion strategy, antifibrinolytic therapy, autologous normovolemic hemodilution, and early extubation in the care of three adolescent males with highly invasive tumors. We demonstrate that new surgical and anesthetic strategies have yielded a significant decrease in intraoperative blood loss and eliminated the need for transfusion of autologous red blood cells, which enable improved outcomes. CONCLUSIONS: The perioperative approach to elective surgery for Juvenile nasopharyngeal angiofibromas management is presented from a multidisciplinary patient blood management perspective.

Patient blood management during the COVID-19 pandemic: a narrative review.

As COVID-19 disease escalates globally, optimising patient outcome during this catastrophic healthcare crisis is the number one priority. The principles of patient blood management are fundamental strategies to improve patient outcomes and should be given high priority in this crisis situation. The aim of this expert review is to provide clinicians and healthcare authorities with information regarding how to apply established principles of patient blood management during the COVID-19 pandemic. In particular, this review considers the impact of the COVID-19 pandemic on blood supply and specifies important aspects of donor management. We discuss how preventative and control measures implemented during the COVID-19 crisis could affect the prevalence of anaemia, and highlight issues regarding the diagnosis and treatment of anaemia in patients requiring elective or emergency surgery. In addition, we review aspects related to patient blood management of critically ill patients with known or suspected COVID-19, and discuss important alterations of the coagulation system in patients hospitalised due to COVID-19. Finally, we address special considerations pertaining to supply-demand and cost-benefit issues of patient blood management during the COVID-19 pandemic.

Predictors of perioperative complications in paediatric cranial vault reconstruction surgery: a multicentre observational study from the Pediatric Craniofacial Collaborative Group.

BACKGROUND: The current incidence of major complications in paediatric craniofacial surgery in North America has not been accurately defined. In this report, the Pediatric Craniofacial Collaborative Group evaluates the incidence and determines the independent predictors of major perioperative complications using a multicentre database. METHODS: The Pediatric Craniofacial Surgery Perioperative Registry was queried for subjects undergoing complex cranial vault reconstruction surgery over a 5-year period. Major perioperative complications were identified through a structured a priori consensus process. Logistic regression was applied to identify predictors of a major perioperative complication with bootstrapping to evaluate discrimination accuracy and provide internal validity of the multivariable model. RESULTS: A total of 1814 patients from 33 institutions in the US and Canada were analysed; 15% were reported to have a major perioperative complication. Multivariable predictors included ASA physical status 3 or 4 (P=0.005), craniofacial syndrome (P=0.008), antifibrinolytic administered (P=0.003), blood product transfusion >50 ml kg-1 (P<0.001), and surgery duration over 5 h (P<0.001). Bootstrapping indicated that the predictive algorithm had good internal validity and excellent discrimination and model performance. A perioperative complication was estimated to increase the hospital length of stay by an average of 3 days (P<0.001). CONCLUSIONS: The predictive algorithm can be used as a prognostic tool to risk stratify patients and thereby potentially reduce morbidity and mortality. Craniofacial teams can utilise these predictors of complications to identify high-risk patients. Based on this information, further prospective quality improvement initiatives may decrease complications, and reduce morbidity and mortality.

Autosomal recessive hereditary spastic paraplegia-clinical and genetic characteristics of a well-defined cohort.

We describe the clinical and genetic features of a well-characterized cohort of patients with autosomal recessive hereditary spastic paraplegia (ARHSP) in the province of Ontario. Patients with documented corticospinal tract abnormalities were screened by whole gene sequencing and multiplex ligation probe amplification for mutations in nine genes known to cause ARHSP. Of a cohort of 39 patients, a genetic diagnosis was established in 17 (44 %) and heterozygous mutations were detected in 8 (21 %). Mutations were most frequent in SPG7 (12 patients), followed by SPG11 (10 patients), PNPLA6 (SPG39, 2 patients), and ZFYVE26 (SPG15, 2 patients). Although there are associations between some clinical manifestations of ARHSP and specific genes, many patients are tested at an early stage of the disease when phenotype/genotype correlations are not obvious. Accurate molecular characterization of well-phenotyped cohorts of patients will be essential to establishing the natural history of these rare degenerative disorders to enable future clinical trials.

Molecular and clinical characterization of de novo and familial cases with microduplication 3q29: guidelines for copy number variation case reporting.

Microdeletions of 3q29 have previously been reported, but the postulated reciprocal microduplication has only recently been observed. Here, cases from four families, two ascertained in Toronto (Canada) and one each from Edinburgh (UK) and Leiden (Netherlands), carrying microduplications of 3q29 are presented. These families have been characterized by cytogenetic and molecular techniques, and all individuals have been further characterized with genome-wide, high density single nucleotide polymorphism (SNP) arrays run at a single centre (The Centre for Applied Genomics, Toronto). In addition to polymorphic copy-number variants (CNV), all carry duplications of 3q29 ranging in size from 1.9 to 2.4 Mb, encompassing multiple genes and defining a minimum region of overlap of about 1.6 Mb bounded by clusters of segmental duplications that is remarkably similar in location to previously reported 3q29 microdeletions. Consistent with other reports, the phenotype is variable, although developmental delay and significant ophthalmological findings were recurrent, suggesting that dosage sensitivity of genes located within 3q29 is important for eye and CNS development. We also consider CNVs found elsewhere in the genome for their contribution to the phenotype. We conclude by providing preliminary guidelines for management and anticipatory care of families with this microduplication, thereby establishing a standard for CNV reporting.

Hemostatic changes in pediatric neurosurgical patients as evaluated by thrombelastograph.

UNLABELLED: Thromboembolic events are a known complication in neurosurgical patients. There is evidence to suggest that a hypercoagulable state may develop perioperatively. Thrombelastograph (TEG) coagulation analysis is a reliable method of evaluating hypercoagulability. We evaluated coagulation by using TEG data in pediatric neurosurgical patients undergoing craniotomy to determine whether a hypercoagulable state develops intraoperatively or postoperatively. Thirty children undergoing craniotomy for removal of a tumor or seizure focus were studied. Blood was analyzed with TEG) data by using native and celite techniques, at three time points for each patient: preoperatively after induction of anesthesia; intraoperatively during closure of the dura; and on the first postoperative day. Compared with preoperative indices, closing and postoperative celite TEG values were indicative of hypercoagulability with shortened coagulation time values (P < 0.001), prolonged alpha angle divergence values (P < 0.001), and above-normal TEG coagulation indices (P < or = 0.002). Reaction time values were shortened, and maximal amplitude of clot strength values were prolonged but did not reach statistical significance. Hypercoagulation develops early after resection of brain tissue in pediatric neurosurgical patients as assessed by using TEG data. Further studies are needed to determine the clinical significance of this hypercoagulable state. IMPLICATIONS: Hypercoagulability in postoperative neurosurgical patients has been demonstrated in the adult population, but few studies have dealt with the pediatric population. We found that children undergoing craniotomy for focal resection, lobectomy, and hemispherectomy are hypercoagulable as detected by thrombelastograph coagulation analysis. Further studies are needed to determine whether this is clinically significant.

Shwachman-Diamond syndrome with exocrine pancreatic dysfunction and bone marrow failure maps to the centromeric region of chromosome 7.

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder characterized by exocrine pancreatic insufficiency and hematologic and skeletal abnormalities. A genomewide scan of families with SDS was terminated at approximately 50% completion, with the identification of chromosome 7 markers that showed linkage with the disease. Finer mapping revealed significant linkage across a broad interval that included the centromere. The maximum two-point LOD score was 8.7, with D7S473, at a recombination fraction of 0. The maximum multipoint LOD score was 10, in the interval between D7S499 and D7S482 (5.4 cM on the female map and 0 cM on the male map), a region delimited by recombinant events detected in affected children. Evidence from all 15 of the multiplex families analyzed provided support for the linkage, consistent with a single locus for SDS. However, the presence of several different mutations is suggested by the heterogeneity of disease-associated haplotypes in the candidate region.

Segregation analysis in Shwachman-Diamond syndrome: evidence for recessive inheritance.

Shwachman-Diamond syndrome is a rare disorder of unknown cause. Reports have indicated the occurrence of affected siblings, but formal segregation analysis has not been performed. In families collected for genetic studies, the mean paternal age and mean difference in parental ages were found to be consistent with the general population. We determined estimates of segregation proportion in a cohort of 84 patients with complete sibship data under the assumption of complete ascertainment, using the Li and Mantel estimator, and of single ascertainment with the Davie modification. A third estimate was also computed with the expectation-maximization (EM) algorithm. All three estimates supported an autosomal recessive mode of inheritance, but complete ascertainment was found to be unlikely. Although there are no overt signs of disease in adult carriers (parents), the use of serum trypsinogen levels to indicate exocrine pancreatic dysfunction was evaluated as a potential measure for heterozygote expression. No consistent differences were found in levels between parents and a normal control population. Although genetic heterogeneity cannot be excluded, our results indicate that simulation and genetic analyses of Shwachman-Diamond syndrome should consider a recessive model of inheritance.

Exclusion of linkage of Shwachman-Diamond syndrome to chromosome regions 6q and 12q implicated by a de novo translocation.

Shwachman-Diamond syndrome is a rare genetic disorder of unknown pathogenesis involving exocrine pancreatic insufficiency and hematological and skeletal abnormalities. There is broad clinical variability; the extent of heterogeneity is unknown but comparisons within a large cohort of patients show no striking differences between patients of families with single or multiple affected offspring. Segregation analysis of a cohort of 69 families has suggested an autosomal recessive mode of inheritance. A single constitutional de novo chromosome rearrangement was reported in a Japanese patient involving a balanced translocation, t(6;12)(q16.2;q21.2), thereby suggesting possible loci for a genetic defect. Evenly spaced microsatellite markers spanning 26-32 cM intervals from D6S1056 to D6S304 and D12S375 to D12S346 were analyzed for linkage in members of 13 Shwachman-Diamond syndrome families with two or three affected children. Two-point lod scores were calculated for each marker under assumptions of recessive inheritance and complete penetrance. Negative lod scores indicated exclusion of both chromosome regions. Further, affected sibs were discordant for inheritance of chromosomes in most families based on constructed haplotypes. The cytogenetic abnormality is not associated with most cases of Shwachman-Diamond syndrome.

Genetic analysis of familial myelodysplastic syndrome: absence of linkage to chromosomes 5q31 and 7q22.

Myelodysplastic syndrome (MDS) is a hematological disorder that occurs primarily in the elderly as an acquired, sporadic disease. Familial cases of MDS are rare. We have identified a kindred with three affected individuals, with early age of onset, suggesting a possible inherited predisposition to this disease. Using a molecular genetic approach, we examined whether bands 5q31 or 7q22 or both, the chromosomal regions most frequently associated with sporadic MDS, are involved in familial expression of MDS in this pedigree. Linkage analysis using polymorphic microsatellite DNA markers demonstrated that neither 5q31 nor 7q22 cosegregated with MDS in this family. There was no history of common environmental or occupational exposure among family members with MDS. In addition, analysis of polymorphisms at two loci [glutathione S-transferase T1 and M1 (GSTT1 and GSTM1)] involved in carcinogen detoxification and associated with cancer susceptibility, including increased risk for MDS, showed no evidence for enhanced sensitivity to environmental carcinogens in affected family members. Taken together, our findings suggest that (1) there is an inherited predisposition to MDS in this kindred; and (2) genes at 5q31 and 7q22, the regions most commonly associated with sporadic MDS, are excluded from a causal role in this family's disease.