Adenotonsillectomy in children with von Willebrand disease

[Does a preoperative coagulation sheet change the postoperative bleeding rate after adenoidectomy?]

BACKGROUND

Adenoidectomy (AT) represents one of the first and most common surgeries in childhood. A joint statement of the German Society for Anesthesiology & Intensive Care Medicine as well as Pediatric & Adolescent Medicine and Otolaryngology, Head and Neck Surgery was published in 2006 to prevent of a possibly life-threatening postoperative bleeding after AT in Child age. Routine blood sampling should be avoided during preoperative preparations and instead a standardized coagulation questionnaire (GB) should be performed to clarify a coagulation disorder (GS). If the GB is abnormal, there is an indication for coagulation diagnostics (GD).

MATERIALS AND METHODS

This unicenter, nonrandomized, retrospective study compared the rate of bleeding after AT and Re-AT without (2011 to early 2014) and with (early 2014 to 2018) the use of a GB. 2633 children aged one to six years, were included in the statistical analysis to assess whether the introduction of GB in early 2014 was able to reduce the rate of bleeding after AT and Re-AT.

RESULTS

Of the 2633 children, 1451 had GB and 1182 did not. Without GB, there was a bleeding rate of 0.83% and 2,08% with GB. 174 GB were abnormal and 169 GD were performed, 164 of these were unremarkable, 2 resulted in a confirmed mild type 1 von Willebrand syndrome as well as 2 suspected vWS and 1 suspected factor VII deficiency. The sensitivity of the GB was 16% and the specificity was 87.5%. The positive predictive value was 2.8% and the negative predictive value was 98%.

CONCLUSION

The GB is a tool for detecting possible GS, but is not useful for reducing the rate of postoperative bleeding.

Clinical, economic, and health-related quality of life burden associated with von Willebrand disease in adults and children: Systematic and targeted literature reviews

INTRODUCTION

Debilitating clinical complications in von Willebrand disease (VWD) can affect health-related quality of life (HRQoL), increase healthcare costs and cause long-lasting consequences. However, the magnitude of these burdens needs to be more fully explored.

AIM

To estimate the prevalence and burden of clinical complications, the impact on HRQoL and the economic burden associated with VWD.

METHODS

Embase^® , MEDLINE^® , the Cochrane Library and conference proceedings were searched for studies on VWD evaluating clinical complications, HRQoL and cost and resource use.

RESULTS

Among 16 studies assessing clinical complications in VWD, the most prevalent bleeding symptoms were menorrhagia (2%-95% [n = 7 studies]), epistaxis (12%-80% [n = 6]) and easy bruising (46%-65% [n = 2]). Among 17 studies evaluating HRQoL, the most common assessment scales were the generic SF-36 (n = 8 studies) and the EQ-5D (n = 2). Bleeding symptoms were associated with reduced QoL in six of seven studies, and of six studies evaluating treatment impact, four reported improvements in one or more HRQoL components. Among 25 studies on cost and resource use, key observations included higher post-surgery healthcare costs in VWD versus non-VWD patients (n = 1 study) and higher costs and resource use in VWD patients with bleeding complications versus those without (n = 1).

CONCLUSION

Although limited, available evidence suggests that VWD patients experience a high burden of clinical complications, reduced QoL and high healthcare costs. Haemarthrosis is more common in severe VWD than is often assumed, and bleeds (including haemarthrosis) can reduce QoL. Research efforts to improve QoL and other outcomes should be prioritized.

The Effect of Desmopressin Intraoperatively on Hemorrhage During the Rhinoplasty Surgery

This clinical trial discusses the efficacy of premedication with desmopressin in the management of bleeding and clears the surgical field during rhinoplasty surgery. This study is a randomized, double-blinded placebo-control clinical trial. Seventy patients were enrolled in this study and divided into two equal intervention-control groups. Thirty minutes before surgery, the intervention group received 500 ml of normal saline containing 0.1 μg/kg desmopressin and, the control group received 500 ml of normal saline. According to the surgeon's opinion, the local distribution of bleeding was dramatically different in both groups. While DDAVP receivers had grade 1 or 2 bleeding (according to the FROMME-BOEZAART grading score), the control group had grade 3 or 4 bleeding, and this difference was statistically meaningful. It seems that intravenous DDAVP can reduce bleeding and clear the surgical field during rhinoplasty surgery, but further studies are needed to determine the exact role and dose of the DDAVP.

Management of Recurrent and Delayed Post-Tonsillectomy and Adenoidectomy Hemorrhage in Children

OBJECTIVE

To review our experience on post-tonsillectomy and/or adenoidectomy hemorrhage (PTAH) at a tertiary pediatric referral hospital and to evaluate the management and risk factors for recurrent postoperative hemorrhage and for delayed bleeding after day 14.

METHODS

A retrospective chart review was performed for all pediatric patients admitted to The Children's Hospital at Westmead for PTAH between July 01, 2014, and June 30, 2019. Patients with recurrent hemorrhage and those with bleeding after day 14 were selected for subanalysis.

RESULTS

Of the 291 patients admitted for PTAH, 31 (11%) patients had recurrent postoperative hemorrhage, and 11 (4%) patients had delayed bleeding after day 14. Surgical intervention for cessation of hemorrhage was required in 88 (30%) patients, including 2 patients who required return to the theater more than once. Nine (3%) patients received blood transfusions. The average number of days between bleeding episodes was 4 days. Recurrent postoperative hemorrhage occurred in 8.5% of patients who were managed operatively at their first presentation compared to 11.4% of patients who were managed nonoperatively (odds ratio: 1.1; 95% confidence interval 0.43-2.8). No association was found between abnormal coagulation profile, surgical indication, and risk of delayed postoperative hemorrhage.

CONCLUSIONS

Recurrent or delayed postoperative hemorrhage represents a small proportion of children with postoperative bleeding and cannot be reliably predicted. Management of first presentations with either a conservative or a surgical approach is reasonable since the risk of recurrent of PTAH may be unrelated to the choice of management at initial presentation. Careful preoperative counseling of patients and their families is important to help set expectations in the event of PTAH.

Perioperative management of a pediatric patient with suspected type 1 von Willebrand disease undergoing tonsillectomy: a case report

Background

Von Willebrand disease (VWD) is the most common inherited bleeding disorder in humans. Coagulopathies such as VWD are evidently risk factors for post-surgical bleeding. Perioperative management of patients with VWD remains controversial and is a major clinical concern.

Case presentation

A 5-year-old girl was scheduled for tonsillectomy under general anesthesia. Preoperative laboratory tests revealed prolongation of activated partial thromboplastin time and a mild decrease in von Willebrand factor (VWF) activity. Prophylactic administration of desmopressin or VWF was not performed. During tonsillectomy, oozing from the surgical wound was uncontrollable by conventional hemostasis techniques, but complete hemostasis was ensured by plasma-derived coagulation factor VIII concentrate containing VWF.

Conclusion

Pediatric patients with mild abnormalities in preoperative laboratory tests may have coagulopathies. Prophylactic intervention and/or the preparation of a sufficient amount of coagulation factor VIII concentrate containing VWF may be required in patients suspected of having VWD or with mild VWF deficiency.

Perioperative Desmopressin for Patients Undergoing Otolaryngologic Procedures: A Systematic Review

Objective

Desmopressin (DDAVP) is a hemostatic agent used to manage bleeding in patients with hemostatic disorders, and there is a lack of published data to guide its use during otolaryngology procedures. The objective of this study was to conduct an evidence-based systematic review of the reported uses, efficacy, and adverse effects of DDAVP in the otolaryngology surgical setting.

Data Sources

PubMed, MEDLINE, and EmBase were searched for articles on the use of DDAVP in otolaryngology.

Review Methods

The Methodological Index for Non-Randomized Studies criteria and Cochrane bias tool were used to assess study quality. Patient demographics, DDAVP dosing and route, and outcomes such as bleeding and adverse events were collected. A summary of evidence table was created specifying levels of evidence, benefits, and harm.

Results

Nineteen studies encompassing 440 patients were included. Sixteen studies discussed DDAVP for prophylaxis, and 3 discussed postoperative use. DDAVP effectively prevented bleeding in high-risk patients and successfully facilitated a dry surgical field when necessary. DDAVP had a 100% success rate when used symptomatically. Five studies described adverse effects, including hyponatremia (12.3%), nausea (2.0%), emesis (0.9%), and seizure (0.2%). The aggregate level of evidence for its use was Level B for adenotonsillectomy, septoplasty, and turbinate procedures and Level C for rhinoplasty.

Conclusion

Current literature supports the use of DDAVP in otolaryngology surgical procedures as both a perioperative prophylactic agent and a postoperative symptomatic intervention for bleeding. Both modalities are effective with minimal adverse events. Further well-designed randomized trials are necessary to conclusively formulate guidelines for DDAVP use in otolaryngology.

Post-tonsillectomy hemorrhagic outcomes in children with bleeding disorders at a single institution

OBJECTIVE

To report on the post-tonsillectomy bleeding outcomes and factors associated with hemorrhage among children with pre- or post-operatively diagnosed bleeding disorders treated with an institutional protocol.

METHODS

Retrospective cohort study of patients with hematologic disorders who underwent tonsillectomy between 2003 and 2016 and were treated with perioperative desmopressin or factor replacement and/or aminocaproic acid. Postoperative outcomes were compared to controls matched for age, sex, and indication for surgery. Analysis of factors associated with hemorrhage was performed in patients with bleeding disorders using Mann-Whitney U or chi-squared tests.

RESULTS

45 patients with hematologic disorders met inclusion criteria. Platelet dysfunction, including von Willebrand Disease (vWD), was the most common diagnosis (77.8%). Most patients had a preoperative diagnosis of a bleeding disorder and received perioperative hematologic medications (86.7%). Compared to matched controls, patients with hematologic disorders experienced more postoperative bleeding (15.5%; 12 bleeds, 7 patients vs. 1.7%; 1 bleed, 1 patient, p = 0.05) and had longer postoperative stays (1.3 days vs. 0.4 days, p < 0.001). Among the patients with hematologic disorders, patients who experienced a postoperative bleed were significantly more likely to have a factor deficiency (e.g. Hemophilia over vWD) and have a postoperative diagnosis (compared to preoperative diagnosis) for which they did not receive perioperative hematologic medication. Of patients with a postoperative bleed, all those diagnosed postoperatively required at least one surgical intervention to control bleeding compared to 33% of patients with a preoperative diagnosis. A history of post-surgical bleeding, male sex, age at surgery, and pharyngitis as surgical indication were not associated with higher hemorrhage rates in this group.

CONCLUSIONS

This study suggests a clinically important magnitude of increased bleeding risk in patients with hematologic disease. This risk appears to decrease with the use of an institutional protocol consisting of desmopressin or factor replacement and an antifibrinolytic agent extending through postoperative day 10.

An update on type 2B von Willebrand disease

Type 2B von Willebrand disease (VWD) accounts for fewer than 5% of all VWD patients. In this disease, mutations in the A1 domain result in increased von Willebrand factor (VWF) binding to platelet GPIbα receptors, causing increased platelet clearance and preferential loss of high molecular weight VWF multimers. Diagnosis is complicated because of significant clinical variations even among patients with identical mutations. Platelet transfusion often provides suboptimal results since transfused platelets may be aggregated by the patients' abnormal VWF. Desmopressin may cause a transient decrease in platelet count that could lead to an increased risk of bleeding. Replacement therapy with factor VIII/VWF concentrates is the most effective approach to prevention and treatment of bleeding in type 2B VWD.

Management of children with inherited mild bleeding disorders undergoing adenotonsillar procedures

OBJECTIVE

To evaluate the incidence of perioperative bleeding among children with mild bleeding disorders who underwent adenotonsillar surgery in our hospital and were treated with our perioperative bleeding prophylaxis protocol.

METHODS

Retrospective chart review was aimed at determining the perioperative bleeding rate in children with mild bleeding disorders subjected to our prophylactic protocol while undergoing adenotonsillar procedures. Low von Willebrand factor (LVWF), unspecific platelet function disorders (UPFD) and mild factor VII deficiency were considered as mild bleeding disorders. The protocol utilizes intravenous desmopressin, tranexamic acid, NSAID avoidance, and overnight observation.

RESULTS

Between 2004 and 2009, 44 children with mild bleeding disorders underwent adenotonsillar procedures in our hospital and were treated with the protocol. One patient (LVWF+UPFD) developed perioperative bleeding (2.3%).

CONCLUSIONS

It is possible to obtain low rates of perioperative bleeding in children with mild bleeding disorders undergoing adenotonsillar procedures, provided there is a well-timed diagnosis and an adequate prophylaxis protocol. We believe that further efforts must be directed at preoperative diagnosis of mild bleeding disorders to ensure safer surgeries.

Complications of adenotonsillectomy

PURPOSE OF REVIEW

Tonsillectomy and adenoidectomy are two of the most commonly performed pediatric surgical procedures. As with all surgical intervention, tonsillectomy and adenoidectomy are associated with a host of potential complications. Fortunately, for most children undergoing adenotonsillectomy (T&A), complications are rare. This review is intended to summarize recent reports, which may lead to prevention and treatment of T&A complications.

RECENT FINDINGS

The presented reports of complications and risk factors for complications in children undergoing T&A highlight perioperative medical management as a means to decrease perioperative complications. Certain tonsillectomy techniques, such as microdebrider intracapsular tonsillectomy, may lead to decreased posttonsillectomy hemorrhage and dehydration. Despite published recommendations, preoperative assessments for bleeding diatheses vary among practitioners. Conversely, guidelines for evaluation of posttonsillectomy hemorrhage are lacking. Some pediatric populations, such as children with coagulopathy, neurologic disease, and obesity, have increased risk of perioperative complications, and recent reports regarding their care are presented.

SUMMARY

We present recent data pertinent to the contemporary management of medical and surgical complications of T&A, with particular focus on specific at-risk pediatric populations. In the patient groups illustrated in this review, anticipation of complications may decrease complications or lead to improved management of complications when they occur.

Perioperative incidence and management of hyponatremia in vWD patients undergoing adenotonsillectomy

OBJECTIVES/HYPOTHESIS

To analyze the incidence and severity of hyponatremia in patients receiving synthetic desmopressin (DDAVP) in the perioperative setting of oropharyngeal surgery in the treatment of von Willebrand disease and to propose a standardized protocol for perioperative fluid resuscitation and postoperative sodium monitoring after DDAVP administration.

STUDY DESIGN

Retrospective medical record review.

METHODS

A retrospective medical record review in an academic pediatric medical center was conducted. From October 1, 2002, to February 1, 2009, all patients undergoing adenotonsillectomy and receiving DDAVP preoperatively for the treatment of von Willebrand disease were identified. A total of 76 patients were identified by initial database review; 63 patients were included in the study, and 13 patients were excluded secondary to incomplete data. DDAVP dose and timing, perioperative fluid volume and composition, and postoperative sodium levels were collected. Extreme adverse events related to hyponatremia were recorded.

RESULTS

Forty-seven of 63 (74.6%) patients developed some degree of hyponatremia after DDAVP administration, and six of 63 (9.5%) patients developed extreme hyponatremia, with the degree of hyponatremia related to the volume of perioperative fluid resuscitation. The sodium nadir occurred within 9 to 20 hours after DDAVP administration. No serious adverse events related to hyponatremia were recorded during the study period.

CONCLUSIONS

The incidence of hyponatremia in children receiving DDAVP for prophylaxis of intraoperative bleeding following oropharyngeal surgery is high. The degree of hyponatremia is related to the perioperative fluid volume administered. A protocol for DDAVP administration, perioperative fluid resuscitation, and postoperative sodium monitoring that aims to reduce the incidence of hyponatremia in this population is proposed.

Significance of advanced haemostasis investigation in recurrent, severe post-tonsillectomy bleeding

Objective:

To evaluate the significance of advanced post-operative haemostasis investigation in cases of recurrent, severe post-tonsillectomy bleeding.

Materials and methods:

Of the 120 patients treated at our tertiary centre between 2006 and 2010 due to post-tonsillectomy haemorrhage, 22 with recurrent, severe episodes of bleeding underwent further, advanced haemostasis investigation.

Results:

Underlying haemorrhagic disease was not diagnosed in any case. Isolated abnormal clotting factor levels were identified in two patients. Decreased fibrinogen concentration due to dilutional coagulopathy was found in nine cases (40.9 per cent).

Conclusion:

Recurrent, severe post-tonsillectomy haemorrhage is rarely related to undiagnosed haemostatic disorders. Thus, advanced haemostasis studies have little therapeutic relevance. However, repetitive post-tonsillectomy bleeding may be related to decreased fibrinogen levels due to dilutional coagulopathy. Therefore, fibrinogen concentration should be tested, and dilutional coagulopathy treated promptly.

A cost-effectiveness analysis of coagulation testing prior to tonsillectomy and adenoidectomy in children

BACKGROUND

The American Society of Pediatric Otolaryngology recommends pre-operative coagulation testing only when indicated by history or physical exam. Nevertheless, many surgeons test all children scheduled for tonsillectomy and/or adenoidectomy (T&A). Studies of pre-operative screening have had conflicting results. A decision analysis model was constructed to address the costs and health outcome states of pre-operative screening strategies in children.

PROCEDURE

A 14-day Markov model evaluated three strategies: (1) test all children for coagulation disorders; (2) test only those children with a pertinent history; and (3) perform no pre-operative testing. A literature search and a review of national databases estimated probabilities, costs, and utility data. Parameters then were varied widely in sensitivity analyses. Using a societal perspective and a cycle length of 1 day, we compared the strategies based on total costs and quality-adjusted life years (QALYs).

RESULTS

Total costs for the strategies were $3,200 for testing all children, $3,083 for testing only those with a history finding, and $3,077 for not testing. Total utilities were 0.02579, 0.02654, and 0.02659 QALYs, respectively. Cost-effectiveness ratios were most sensitive to variation in the cost of post-operative care and the probability of post-operative bleeding. The strategy of not testing was dominant in all sensitivity analyses.

CONCLUSIONS

Our results demonstrate that not performing preoperative testing is the most cost-effective strategy. This was persistent in sensitivity analyses, indicating that the model was robust. These data may be helpful to institutions and organizations to formulate policies regarding pre-operative coagulation for children without previous diagnoses of bleeding disorders.

Cost-utility analysis of von Willebrand disease screening in adolescents with menorrhagia

OBJECTIVE

To construct a decision analysis model to evaluate the cost utility of von Willebrand disease (VWD) testing in adolescents with menorrhagia.

STUDY DESIGN

A 20-year Markov decision analytic model was constructed to evaluate the cost utility of two strategies: testing or not testing for VWD. The model includes probabilities of remaining well, suffering an acute menorrhagia bleeding event, surgical complications, oral contraceptive pill complications, or dying. Probabilities, costs, and utilities were estimated from published literature. The prevalence of type 1 VWD in adolescent females with menorrhagia was estimated at 13%.

RESULTS

The cost of testing adolescents with menorrhagia for VWD was $1790, versus $1251 for not testing for VWD. The effectiveness of not testing in quality-adjusted life-years (QALYs) gained (14.237 QALYs) was similar to the VWD testing strategy (14.246 QALYs). Compared with not testing for VWD, screening for VWD had an incremental cost-effectiveness ratio of $62,791 per QALY, a value typically considered economically reasonable.

CONCLUSIONS

In adolescents with menorrhagia, testing for VWD before the initiation of oral contraceptives is cost-effective.

Post-tonsillectomy bleeding in children with von Willebrand disease: a single-institution experience

OBJECTIVES

1) Compare rates of post-tonsillectomy bleeding in pediatric patients with and without von Willebrand disease (vWD). 2) Identify factors that may increase the risk for post-tonsillectomy bleeding in children with and without vWD.

STUDY DESIGN

Historical cohort study.

SETTING

Tertiary care, university-based pediatric hospital.

SUBJECTS AND METHODS

Medical records were examined for 99 patients with vWD and 99 patients without vWD younger than 18 years who underwent tonsillectomy with or without adenoidectomy from August 1997 to October 2005. Subjects were matched for age, year of surgery, type of surgery, and indication for surgery.

RESULTS

Post-tonsillectomy hemorrhage occurred in eight of 99 (8%) vWD patients and in six of 99 (6%) non-vWD patients (P = 0.58, odds ratio 1.36, 95% CI 0.45-4.08). A two-sample test of proportions demonstrated lower and upper limits of -0.051 and 0.092. Four of eight children with vWD and two of six non-vWD patients required surgical intervention for control of bleeding. Ninety-three of 99 vWD patients received desmopressin acetate (DDAVP) preoperatively. In patients with vWD who responded to DDAVP challenge, there was no increased likelihood of post-tonsillectomy bleeding compared with non-vWD patients. No significant difference in the number of bleeding events was noted on the basis of demographics, preoperative laboratories, or use of aminocaproic acid.

CONCLUSION

Children with vWD undergoing tonsillectomy have a postoperative bleeding rate similar to that of a matched group. However, the sample size was not sufficient to eliminate the possibility of a clinically important difference between the two groups.

Pediatric otolaryngologic manifestations of bleeding disorders

OBJECTIVE

In 1930, considering the diseases of the blood and lymphatic glands in relation to otolaryngology, Goldsmith and McGregor stated that "... the otolaryngologist has frequently to deal with bleeding from the nose and throat ...". After approximately 8 decades, in particular preoperatively, the use of universal coagulation screening in children is still controversial. Aim of the present review was to offer a concise but complete discussion of clotting disorders with pediatric otolaryngological interest recognizing: (i) vascular disorders, (ii) platelet disorders, (iii) disorders of coagulation, and (iv) thrombosis.

METHODS

An exhaustive review of literature was performed to investigate available data and evidences regarding pediatric otolaryngologic manifestations of bleeding disorders.

RESULTS/CONCLUSIONS

Modern otolaryngologists should be familiar with common bleeding disorders since many have head and neck manifestations. This knowledge allows the choice of appropriate pre-operative screening of surgical patients. The most important component of the preoperative assessment is the bleeding history that directs further laboratory evaluation. All otolaryngologic surgical procedures in children with bleeding disorders should be carried out with the close co-operation of the Haematology Department.

Incidence of bleeding complications in pediatric patients with type 1 von Willebrand disease undergoing adenotonsillar procedures

OBJECTIVE

To review the incidence of postoperative bleeding in children with type 1 von Willebrand disease (VWD) who were treated with a single institution protocol.

STUDY DESIGN

We performed a retrospective study to determine the postoperative hemorrhage rate in pediatric patients with type 1 VWD who were treated via the Children's Hospital of Philadelphia institutional protocol. This protocol utilizes intravenous desmopressin (DDAVP), oral aminocaproic acid, and overnight observation.

RESULTS

Between the years of 2000 to 2006, 41 children with type 1 VWD underwent an adenotonsillar procedure and were treated with this protocol. Seven patients (17%) experienced delayed (>24 hours after surgery) postoperative hemorrhage requiring intervention. Five of the 7 patients required cautery to control the bleeding, and the remaining 2 patients responded to DDAVP and aminocaproic acid alone. Older age and lower VW antigen levels were associated with postoperative hemorrhage (P = .05).

CONCLUSIONS

Despite therapeutic intervention to decrease the risk of postoperative hemorrhage, the incidence of hemorrhage was higher in pretreated patients with type 1 VWD than in children without bleeding disorders. Further prospective studies are necessary to determine the optimal treatment to reduce bleeding complications in these patients.

The prevalence of bleeding disorders among healthy pediatric patients with abnormal preprocedural coagulation studies

BACKGROUND

We evaluated the prevalence of hemostatic disorders among pediatric patients with abnormal screening coagulation tests.

PROCEDURE

We analyzed 48 consecutive referrals for abnormal prothrombin times, partial thromboplastin times, or closure times obtained as preprocedural screens. Patients were evaluated by uniform diagnostic testing.

RESULTS

Seventeen patients (35%) had an isolated nonspecific inhibitor (NSI). Six patients (12.5%) presented with mildly low factor activity with a concomitant NSI. These deficiencies were of unclear clinical significance. One patient (2%) had a lupus anticoagulant. Only 9 patients (19%) had a possible or true mild bleeding disorder: 5 patients (10%) had isolated low von Willebrand factor levels, 2 patients (4%) had possible type I von Willebrand disease, and 2 (4%) had platelet aggregation disorders. In all patients, personal and family bleeding history had a positive predictive value of 45% for hemostatic disorders.

CONCLUSIONS

The most common diagnosis among the patients referred to us for abnormal preoperative coagulation tests was a NSI, which is not associated with an increased risk of operative bleeding complications. Less than 20% had a possible or true mild bleeding disorder. Although certain bleeding disorders can be occult in children and are associated with perioperative bleeding risks, our study demonstrates the inherent limitations in making a laboratory diagnosis of a bleeding disorder in pediatric patients preoperatively. Our findings contribute to existing doubt about the usefulness of prothrombin times, partial thromboplastin times, and closure times to identify occult bleeding disorders in this population.

Risiko von Blutungen nach Adenotomie und Tonsillektomie

BACKGROUND

Hemorrhage after tonsillectomy and adenoidectomy remains a serious complication. Therefore, routine preoperative coagulation screening, including activated partial thromboplastin time (aPTT), prothrombin time (PT) and platelet count (PLC), are regularly performed, also for medicolegal reasons. In the recently published statement of the German Society of Otorhinolaryngology, Head and Neck Surgery the need for routine preoperative coagulation screening is discussed, but so far no standardized procedure had been established. According to this statement - at least for children - routine preoperative coagulation screening is not mandatory as long as the thorough medical history provides no evidence for a coagulation disorder ( http://www.hno.org/kollegen/gerinnung_te_ae.html ). The present study was undertaken to determine the occurrence of postoperative hemorrhage on the one hand, and the incidence of abnormal preoperative routine coagulation parameters or pathological anamnesis findings on the other.

PATIENTS AND METHODS

In 688 patients, a standardized clinical history was obtained using a questionnaire. Coagulation screening included aPTT, PT, and PLC was also carried out. Bleeding complications were then correlated with anamnesis features and abnormalities in coagulation screening.

RESULTS

In 39 (5.7%) of the 688 patients we found abnormal coagulation values, which were confirmed in repeated analyses. In six of these a detailed analysis revealed occult coagulation disorders requiring correction only in the case of bleeding complications who were previously unknown. Fifteen patients were already known to have a coagulation disorder, and the anamnesis identified no additional patient at risk. Thus, 21 patients with coagulation disorders requiring correction in the case of a bleeding complication underwent surgery. However, only eight (38%) of these showed abnormal routine coagulation parameters. Surgical treatment of postoperative hemorrhage was required in 12 patients, all of whom had normal values for aPTT, PT and PLC.

CONCLUSION

The frequently performed determination of routine coagulation parameters (aPTT, PT, PLC) is not able to reliably identify relevant coagulation disorders or to predict the risk for postoperative hemorrhagic complications after adenoidectomy or tonsillectomy.

Coagulation Defects

The present understanding of the coagulation process emphasizes the final common pathway and the proteolytic systems that result in the degradation of formed clots and the prevention of unwanted clot formations, as well as a variety of defense systems that include tissue repair, autoimmune processes, arteriosclerosis, tumor growth, the spread of metastases, and defense systems against micro-organisms. This article discusses diagnosis and management of some of the most common bleeding disorders. The goals are to provide a simple guide on how best to manage patients afflicted with congenital or acquired clotting abnormalities during the perioperative period, present a brief overview of the methods of testing and monitoring the coagulation defects, and discuss the appropriate pharmacologic or blood component therapies for each disease.

Valproate-associated coagulopathies are frequent and variable in children

PURPOSE

Valproic acid (VPA) is an antiepileptic drug (AED) commonly used for generalized and focal epilepsies. The clinical relevance of coagulopathies, known as side effects of VPA therapy, especially thrombocytopenia, von Willebrand disease, and a decrease of factor XIII, is still unclear.

METHODS

In our institute, we noticed a high incidence of clinically relevant coagulation problems related to VPA in eight patients within 1 year only and a further seven children with significant coagulopathy were identified in the context of planned surgery.

RESULTS

We provide an overview of these patients and all six VPA-induced coagulopathies.

CONCLUSIONS

At this time, it cannot be recommended to control all hemostatic parameters in every patient. Whenever an increased bleeding tendency is observed, or before surgical procedures, a platelet count, thrombelastography, prothrombin time, activated partial thromboplastin time, TT, fibrinogen, von Willebrand factor, and factor XIII should be examined. With 385 VPA-treated patients per year and 15 cases of coagulation disorders in this period, we estimate the incidence of coagulation disorders related to VPA in children to be nearly 4%.

Desmopressin associated symptomatic hyponatremic hypervolemia in children. Are there predictive factors?

PURPOSE

Desmopressin is widely used in primary nocturnal enuresis, bleeding disorders, central diabetes insipidus and diagnostic urine concentration testing. Hyponatremic hypervolemia leading to seizures has been reported as a rare but potentially life threatening side effect of desmopressin therapy. We sought to identify factors that predispose patients to hyponatremia and to find predictive factors associated with increased risk of water intoxication.

MATERIALS AND METHODS

We report 13 novel cases of desmopressin associated water intoxication and review the literature. A total of 93 instances of symptomatic hyponatremia during desmopressin treatment in children were identified. Specific data were reported in 58 of 93 cases. These 58 cases, in addition to our 13 novel cases, were further analyzed.

RESULTS

All children were treated with intranasal or intravenous desmopressin. No patient received oral desmopressin. Younger children are at greater risk for water intoxication than older children. The risk is particularly high at the beginning of desmopressin therapy. A total of 45 patients (63%) had prodromal symptoms, eg nausea, vomiting and headache. In 10 cases (14%) desmopressin was prescribed without an evident need.

CONCLUSIONS

Based on this analysis, we conclude that the use of desmopressin should be cautiously considered, careful monitoring should be performed during the initiation of therapy, and particular care should be taken when treating young children and when prodromal symptoms such as nausea, vomiting and headaches occur.

[Postoperative hyponatremia in children: pathophysiology, diagnosis and treatment]

OBJECTIVES

To review the current data on pathophysiology, causes and management of postoperative hyponatremia in children.

DATA SOURCES AND EXTRACTION

The Pubmed database was searched for articles, combined with references analysis of major articles on the field.

DATA SYNTHESIS

The incidence of postoperative hyponatremia has been evaluated at 0.34% and its mortality significant. Postoperative hyponatremia is triggered by the diminished renal ability to excrete free water, due to antidiuretic hormone release. Inappropriate secretion of antidiuretic hormone is frequently seen after spine, cardiac and neurosurgery but can occur even after minor surgery. In this context, the infusion of hypotonic fluids represents a strong risk factor for developing hyponatremia. Other causes of hyponatremia are represented by extrarenal fluid losses, cerebral salt wasting syndrome, desalination phenomenon, adrenal insufficiency or some medications. Preventive treatment is essential and based on prohibition of hypotonic fluids infusion and the use of isotonic fluids infusions, maintenance of a normal total blood volume, the observance of the good practice recommendations for fluid infusion in children, and frequent blood and urine sodium concentration determinations in patients at risk for developing hyponatremia. Hyponatremic encephalopathy requires an emergent management, consisting in respiratory care and hypertonic sodium chloride infusion. Chronic hyponatremia is most often asymptomatic and the main neurological risk factor is represented by a too rapid correction of plasma sodium, which may lead to centropontine myelinolysis.

Adenotonsillectomy in children with von Willebrand's disease: how and when. A case report with review of the literature

The presence of coagulation pathology in children who are candidates for adenotonsillectomy (AT) is a challenge to the otolaryngologist. von Willebrand's disease (vWD) is the most common hereditary coagulopathy and is due to a quantitative and/or qualitative deficiency of von Willebrand's factor (vWF). In recent years, the administration of 1-deamino-8-D-arginine vasopressin (DDAVP) has been recommended as coadjuvant therapy for surgical procedure. This synthetic hormone promotes the release of vWF and factor VIII from endothelial cells. In this report, the authors describe the history of a child with vWD undergoing successful AT after administration of DDAVP. Furthermore, a review of the literature with particular emphasis on the use of DDAVP is made.