Blood loss estimation in epistaxis scenarios

Treating epistaxis - who cares for a bleeding nose? A secondary data analysis of primary and secondary care

Background

The primary objective was to describe outpatient treatment of epistaxis among different physicians based on a large patient population over a period of 10 years. The secondary objective was to evaluate the value of the practice fee as an instrument of allocation in patients with epistaxis.

Methods

Anonymized statutory health insurance data (AOK Lower Saxony) of patients with a diagnosis of epistaxis treated between 2007 and 2016 were examined. Demographic data, accompanying diagnoses, medication and involved medical groups (general practitioners (GP), pediatricians, ear, nose and throat (ENT) specialists or other) were analyzed. Furthermore, we assessed whether the use of specialist groups changed after abolition of the practice fee in 2013.

Results

Epistaxis was responsible for 302,782 cases (160,963 patients). The distribution of cases was slightly in favor of ENT specialists vs. GP (119,170 vs. 110,352). The cases seen by GP and ENT specialists were comparable with regard to age and sex distribution. Hypertension, atrial fibrillation/flutter and an antithrombotic therapy were slightly more common among cases consulting a GP. The GP recorded more co-diagnoses than the ENT. The use of outpatient care and the proportions of the involved physicians scarcely fluctuated during the study period. Overall, 23,118 patients (14.4%) were diagnosed by both, GP and ENT during a relatively short time period. The practice fee remuneration had no impact on the consultation of the physician groups.

Conclusion

The outpatient treatment of epistaxis constitutes a considerable medical and economic burden in Germany. Strengthening the primary medical sector (GP-centered care) is necessary to reach the goal of initially directing patients to primary care, providing specialists more time for severe cases and reducing the impact on public health balance sheets.

Accuracy of training blood volume quantification using a visual estimation tool

BACKGROUND

We investigated whether the use of a specially designed visual estimation tool may improve accuracy in quantifying blood volumes related to surface spreading.

METHODS

A prospective, paired-control, single-blinded experimental study was performed at a medical university. Anesthesiologists and emergency medical personnel estimated various blood volumes on surfaces with varying absorptivity (carpet, towel, polyvinyl chloride, wooden flooring) in an experimental setting. We assessed the sensitivity of training blood volume quantification using a self-designed visual estimation tool by comparing the accuracy of visual blood volume estimations before and after practical training with the tool.

RESULTS

A total of 352 estimations by 44 participants were evaluated. Accurate estimations improved significantly from pre-training to post-training (P<0.05). The sensitivity of blood volume quantification was 33.0% after training with the visual estimation tool. Estimations did not depend on age, profession, gender or years of the estimator's professional experience.

CONCLUSIONS

Training with a visual estimation tool by professional rescuers can improve the estimation accuracy of blood volumes spread on surfaces with varying absorptivity.

Visual estimates of blood loss by medical laypeople: Effects of blood loss volume, victim gender, and perspective

A severe hemorrhage can result in death within minutes, before professional first responders have time to arrive. Thus, intervention by bystanders, who may lack medical training, may be necessary to save a victim's life in situations with bleeding injuries. Proper intervention requires that bystanders accurately assess the severity of the injury and respond appropriately. As many bystanders lack tools and training, they are limited in terms of the information they can use in their evaluative process. In hemorrhage situations, visible blood loss may serve as a dominant cue to action. Therefore, understanding how medically untrained bystanders (i.e., laypeople) perceive hemorrhage is important. The purpose of the current study was to investigate the ability of laypeople to visually assess blood loss and to examine factors that may impact accuracy and the classification of injury severity. A total of 125 laypeople watched 78 short videos each of individuals experiencing a hemorrhage. Victim gender, volume of blood lost, and camera perspective were systematically manipulated in the videos. The results revealed that laypeople overestimated small volumes of blood loss (from 50 to 200 ml), and underestimated larger volumes (from 400 to 1900 ml). Larger volumes of blood loss were associated with larger estimation errors. Further, blood loss was underestimated more for female victims than male victims and their hemorrhages were less likely to be classified as life-threatening. These results have implications for training and intervention design.

Comparison of common perioperative blood loss estimation techniques: a systematic review and meta-analysis

Estimating intraoperative blood loss is one of the daily challenges for clinicians. Despite the knowledge of the inaccuracy of visual estimation by anaesthetists and surgeons, this is still the mainstay to estimate surgical blood loss. This review aims at highlighting the strengths and weaknesses of currently used measurement methods. A systematic review of studies on estimation of blood loss was carried out. Studies were included investigating the accuracy of techniques for quantifying blood loss in vivo and in vitro. We excluded nonhuman trials and studies using only monitoring parameters to estimate blood loss. A meta-analysis was performed to evaluate systematic measurement errors of the different methods. Only studies that were compared with a validated reference e.g. Haemoglobin extraction assay were included. 90 studies met the inclusion criteria for systematic review and were analyzed. Six studies were included in the meta-analysis, as only these were conducted with a validated reference. The mixed effect meta-analysis showed the highest correlation to the reference for colorimetric methods (0.93 95% CI 0.91–0.96), followed by gravimetric (0.77 95% CI 0.61–0.93) and finally visual methods (0.61 95% CI 0.40–0.82). The bias for estimated blood loss (ml) was lowest for colorimetric methods (57.59 95% CI 23.88–91.3) compared to the reference, followed by gravimetric (326.36 95% CI 201.65–450.86) and visual methods (456.51 95% CI 395.19–517.83). Of the many studies included, only a few were compared with a validated reference. The majority of the studies chose known imprecise procedures as the method of comparison. Colorimetric methods offer the highest degree of accuracy in blood loss estimation. Systems that use colorimetric techniques have a significant advantage in the real-time assessment of blood loss.

Visual estimation of blood loss by UK pre-hospital clinicians: an observational study

Aim:

To assess the accuracy of visual estimation of external blood loss by UK pre-hospital clinicians and to comment on its value during handover.

Methods:

A sample of 104 pre-hospital clinicians were shown eight staged scenarios showing varying amounts of blood loss and asked to estimate the amount of blood loss depicted. Participants included a range of pre-hospital clinicians from both NHS ambulance trusts and Helicopter Emergency Medical Services.

Results:

A wide distribution of estimates and therefore percentage error was observed in our study. Pre-hospital clinicians are inaccurate when estimating external blood loss at scene, regardless of training and skill level.

Conclusion:

Visual estimation of blood loss is too inaccurate to be considered clinically worthwhile. Greater research focus is needed to investigate and validate better measures of blood loss that can be utilised in the pre-hospital and emergency medicine environment. Until evidence-based methods of estimation can be implemented, this information should not be included in hospital handovers.

Estimated versus measured blood loss during dilation and evacuation: an observational study

OBJECTIVE

To compare estimated versus measured blood loss at the time of dilation and evacuation (D&E).

STUDY DESIGN

We measured blood loss for all D&E procedures between 16 and 24 weeks at one abortion clinic over 9 months. We weighed all blood-containing items and measured blood captured in the D&E tray. Providers recorded estimated blood loss before weighing or measuring blood. We compared median measured blood loss (MBL) and estimated blood loss (EBL) for each gestational week.

RESULTS

We measured blood loss in 371 of the 534 D&Es in the study period; we excluded 163 procedures because of failure to measure blood loss or contamination with amniotic fluid. Included and excluded procedures had similar median EBLs. Median EBL differed significantly from MBL for each week gestation from 16 to 24 weeks (p≤.001 for all comparisons); MBL was approximately twice as high as EBL for each gestational week. EBL and MBL increased with increasing gestation, as did the difference between EBL and MBL.

CONCLUSION

Providers consistently and significantly underestimate blood loss at the time of D&E. D&E providers may want to consider using a new heuristic for estimating blood loss.

IMPLICATIONS

Providers significantly underestimate blood loss at the time of D&E. Future research should confirm these findings (particularly at 22-24 weeks gestation), evaluate the efficacy of interventions to improve estimations of blood loss, and determine best practices for decreasing blood loss.

Accuracy of tablet counts estimated by members of the public and healthcare professionals

Objective

Intentional and accidental drug intoxication is commonly seen in the emergency department. When treating intoxicated patients, accessing the amount of the ingested drug is crucial albeit often difficult. We investigated the accuracy of estimating tablet counts when participants were asked to hold tablets in their fists and hands (semi-quantitative terms).

Methods

The widths and lengths of the participants’ hands were measured. Then, the subjects were asked to hold 5-mm round, 10-mm round, 10-mm oval, and 15-mm elliptical tablets using their hands and fists and to estimate the number of tablets they were holding. Differences between the estimated and actual numbers of tablets were examined.

Results

A total of 47 members of the public and 32 healthcare professionals were included in our study. In our analyses of the differences between the actual and estimated amounts of tablets held in the participants’ hands and fists, we found that the actual amount was higher than the estimated amount for all tablet types and in both groups. When participants held the tablets in the same manner (handful or fistful), the differences between the actual and estimated amounts were greater for 5- than 15-mm-sized tablets (P<0.05).

Conclusion

The treatment of patients presenting with drug overdoses to the emergency department should be based on the assumption that the actual amount of drugs the patients ingested is likely greater than the amount the patients state.

Predictors of clinically significant upper gastrointestinal hemorrhage among children with hematemesis

OBJECTIVES

The aim of the study was to determine the proportion of children with hematemesis who experience a clinically significant upper gastrointestinal hemorrhage (UGIH) and to identify variables predicting their occurrence.

METHODS

A retrospective cohort study was conducted. All of the emergency department visits by children ages 0 to 18 years who presented with hematemesis between 2000 and 2007 were reviewed. The primary aim of the study was to determine the proportion of children who developed a clinically significant UGIH; the secondary aim was to identify risk factors predictive of a clinically significant UGIH. A significant UGIH was defined by any of the following: hemoglobin drop >20 g/L, blood transfusion, or emergent endoscopy or surgical procedure.

RESULTS

Twenty-seven of 613 eligible children (4%; 95% confidence interval 3%-6%) had a clinically significant UGIH. Clinically significant hemorrhages were associated with older age (9.7 vs 2.9 years; P<0.001), vomiting moderate to large amounts of fresh blood (58% vs 20%; P<0.001), melena (37% vs 5%; P<0.001), significant medical history (63% vs 24%; P<0.001), unwell appearance (44% vs 6%; P<0.001), and tachycardia (41% vs 10%; P<0.001). The frequency of laboratory investigations increased with age (P<0.001). The hemoglobin level was the only laboratory investigation whose results differed between those with and without significant bleeds. The presence of any one of the following characteristics identified all of the children with a clinically significant hemorrhage: melena, hematochezia, unwell appearance, or a moderate to large volume of fresh blood in the vomitus, sensitivity 100% (95% confidence interval 85%-100%).

CONCLUSIONS

The occurrence of a clinically significant UGIH was uncommon among children with hematemesis, especially in well-appearing children without melena, hematochezia, or who had not vomited a moderate to large amount of fresh blood.

Unreliability of intraoperative estimated blood loss in extended sagittal synostectomies

OBJECT

Intraoperative blood loss represents a significant concern during open repair of craniosynostosis, and its reliable measurement remains a serious challenge. In this study of extended sagittal synostectomies, the authors analyzed the relationship between estimated blood loss (EBL) and calculated blood loss (CBL), and investigated predictors of hemodynamic outcomes.

METHODS

The authors reviewed outcomes in infants with sagittal synostosis who underwent primary extended synostectomies (the so-called Pi procedure) between 1997 and 2009. Patient demographic data, operating time, and mean arterial pressures (MAPs) were recorded. Serial MAPs were averaged for a MAP(mean). The EBL was based on anesthesia records, and the CBL on pre- and postoperative hemoglobin values in concert with transfusion volumes. Factors associated with EBL, CBL, red blood cell transfusion (RBCT), and hospital length of stay (LOS) were investigated. Hemodynamic outcomes were reported as percent estimated blood volume (% EBV), and relationships were analyzed using simple and multiple linear and logistic regression models. A p value < 0.05 was considered significant.

RESULTS

Seventy-one infants with sagittal synostosis underwent primary extended synostectomies at a mean age and weight of 4.9 months and 7.3 kg, respectively. The average operating time was 1.4 hours, and intraoperative MAP was 54.6 mm Hg (21.3% lower than preoperative baseline). There was no association between mean EBL (12.7% EBV) and mean CBL (23.6% EBV) (r = 0.059, p = 0.63). The EBL inversely correlated with the patient's age (r = -0.07) and weight (r = -0.11) at surgery (p < 0.05 in both instances). With regard to intraoperative factors, EBL positively trended with operating time (r = 0.26, p = 0.09) and CBL inversely trended with MAP(mean) (r = -0.04, p = 0.10), although these relationships were only borderline significant. Intraoperative RBCT, which was required in 59.1% of patients, positively correlated with EBL (r = 1.55, p < 0.001), yet negatively trended with CBL (r = -0.40, p = 0.01). Undertransfusion was significantly more common than overtransfusion (40.8% vs 22.5%, p = 0.02, respectively). The mean hospital LOS was 2.3 days and was not significantly associated with patient demographic characteristics, intraoperative factors, blood loss, RBCT, or total fluid requirements.

CONCLUSIONS

In extended synostectomies for sagittal synostosis, EBL and CBL demonstrated a decided lack of correlation with one another. Intraoperative blood transfusion positively correlated with EBL, but inversely correlated with CBL, with a significantly higher proportion of patients undertransfused than overtransfused. These findings highlight the need for reliable, real-time monitoring of intraoperative blood loss to provide improved guidance for blood and fluid resuscitation.

Intractable anemia: a case of bleeding nasal cavernous hemangioma

Cavernous haemangioma of the nose is rare, but when it occurs it usually presents with severe epistaxis. This nasal pathology is mostly seen in adult patient patients. Standard approach to dealing with such haemangiomas is surgical resection. A 30-year-old woman presented to General Physician with history of haemoptysis, haematemesis and weakness. She was admitted for investigation of her severe anaemia. On examination there was no obvious source of bleeding in the mouth or oropharynx, and Upper GI endoscopy did not reveal any pathology. She was referred to us after a trivial episode of epistaxis. Anterior and posterior rhinoscopy did not reveal any abnormality. Her extreme anxiety made indirect laryngoscopy and post-nasal space examination difficult but no obvious abnormality was seen. Diagnostic nasal endoscopy was done, and a small haemangiomatous mass was found in the postero superior part of inferior turbinate. Excision of the mass was done under local anaesthesia and sent for histopathological evaluation. The mass on histopathology came out to be Cavernous haemangioma.

Measurement of blood loss: review of the literature

It is important to recognize excessive blood loss during childbirth, which is a significant cause of morbidity and mortality. This article reviews methods to measure blood loss that could be used during childbirth. PubMed, CINAHL, and MEDLINE databases were searched using the phrases "blood loss" and "measurement." The bibliographies of publications were scanned for applicable references. A total of 46 publications are included in this review. The methods used to measure blood loss are categorized into visual estimation, direct measurement, gravimetric, photometry, and miscellaneous. Methods are described and compared. A combination of direct measurement and gravimetric methods are the most practical. Photometry is the most precise, but also the most expensive and complex to use. A variety of miscellaneous methods are presented, but none is a practical or reliable method. Visual estimation of blood loss is so inaccurate that its continued use in practice is questionable and it should not be used in research to evaluate treatment.

Trends in postpartum hemorrhage in high resource countries: a review and recommendations from the International Postpartum Hemorrhage Collaborative Group

BACKGROUND

Postpartum hemorrhage (PPH) is a major cause of maternal mortality and morbidity worldwide. Several recent publications have noted an increasing trend in incidence over time. The international PPH collaboration was convened to explore the observed trends and to set out actions to address the factors identified.

METHODS

We reviewed available data sources on the incidence of PPH over time in Australia, Belgium, Canada, France, the United Kingdom and the USA. Where information was available, the incidence of PPH was stratified by cause.

RESULTS

We observed an increasing trend in PPH, using heterogeneous definitions, in Australia, Canada, the UK and the USA. The observed increase in PPH in Australia, Canada and the USA was limited solely to immediate/atonic PPH. We noted increasing rates of severe adverse outcomes due to hemorrhage in Australia, Canada, the UK and the USA.

CONCLUSION

Key Recommendations 1. Future revisions of the International Classification of Diseases should include separate codes for atonic PPH and PPH immediately following childbirth that is due to other causes. Also, additional codes are required for placenta accreta/percreta/increta. 2. Definitions of PPH should be unified; further research is required to investigate how definitions are applied in practice to the coding of data. 3. Additional improvement in the collection of data concerning PPH is required, specifically including a measure of severity. 4. Further research is required to determine whether an increased rate of reported PPH is also observed in other countries, and to further investigate potential risk factors including increased duration of labor, obesity and changes in second and third stage management practice. 5. Training should be provided to all staff involved in maternity care concerning assessment of blood loss and the monitoring of women after childbirth. This is key to reducing the severity of PPH and preventing any adverse outcomes. 6. Clinicians should be more vigilant given the possibility that the frequency and severity of PPH has in fact increased. This applies particularly to small hospitals with relatively few deliveries where management protocols may not be defined adequately and drugs or equipment may not be on hand to deal with unexpected severe PPH.

Estimating blood loss: comparative study of the accuracy of parents and health care professionals

OBJECTIVE

Hematemesis and hematochezia are not uncommon presenting complaints in children. The amount of blood loss reported by the parent is likely to influence the pediatrician's decision regarding investigations and management. Currently, there are only very limited data regarding the ability of laypersons to estimate blood losses visually. This study investigated the accuracy of parents, in comparison to pediatric health care professionals, in estimating blood loss volumes.

PATIENTS AND METHODS

We performed a prospective, single-blinded study including 227 participants, comprising 131 parents, 58 nurses, and 38 doctors. Participants visually estimated the volume of 1 randomly allocated sample from each of the 2 categories: (1) 1, 5, or 10 mL of artificial blood applied to a diaper (simulated hematochezia) and (2) 5, 10, or 50 mL placed in a kidney-dish (simulated hematemesis). An "error factor" (=, estimated volume/actual volume shown) was used to facilitate comparisons.

RESULTS

Parents provided the most inaccurate estimates overall, although individual accuracy varied considerably. The largest overestimate (518 mL) and the highest error factor (23.4) were recorded in a parent; overall, 71% of the estimates provided by parents were overestimates. The highest proportion of accurate estimates (+/-50% of actual volume) was recorded by nurses (29%). Doctors had a tendency to underestimate volumes (62% of the estimates were less than half the actual volume). However, there was no statistically significant difference between the performance of nurses and doctors. Health care professionals tended to overestimate small volumes and underestimate large volumes. Professional experience had no relevant impact on accuracy, nor did parental gender or age.

CONCLUSIONS

Visual estimation of blood losses is highly inaccurate, both by laypersons and by health care professionals. Physicians should, therefore, base management decisions primarily on clinical findings and not overly rely on the history provided, or their own estimates.

Estimation of external blood loss by paramedics: is there any point?

OBJECTIVES

There are many patient assessment challenges in the prehospital setting, especially the estimation of external blood loss. Previous studies of experienced paramedics have demonstrated that external blood loss estimation is highly inaccurate. The objective of this study was to determine if undergraduate paramedic students could accurately estimate external blood loss on four surfaces commonly found in the prehospital environment.

METHODS

This prospective, observational, blinded study used a convenience sample of undergraduate students studying at Monash University during 2006. Students were provided with four clinical vignettes using four different surfaces and varying simulated blood amounts.

RESULTS

Accurate estimation occurred with the vinyl simulation (100 ml), with a mean value of the estimations of 98 ml (95% Confidence Interval (CI) 84-113 ml). Carpet and concrete surfaces were both associated with large under-estimations. The carpet simulation (1,000 ml) had a mean value for the estimations of 347 ml (95% CI 320-429 ml). The concrete simulation (1,500 ml) had a mean value for the estimations of 885ml (95% CI 771-999 ml). Conversely, the clothing simulation (500 ml) emphasized over-estimation, with a mean value for the estimations of 1,253 ml (95% CI 1,093-1,414 ml). There was no relationship between increased accuracy and clinical experience, exposure, educational qualifications, or age of students.

CONCLUSIONS

External blood loss estimation by undergraduate paramedic students generally is too inaccurate to be of any clinical benefit. Particularly, absorbent and impermeable surfaces precipitated inaccuracies by undergraduate paramedic students.

"About a cupful"--a prospective study into accuracy of volume estimation by medical and nursing staff

In this prospective study, medical and nursing health care professionals were asked to visually estimate various fluid volumes. The aims were to assess overall accuracy, and to identify factors that caused error. The effects of fluid volume, colour and clinical experience were analysed. 152 doctors and nurses were shown a selection of containers filled with five different volumes of fluid, each presented in three different colours. Subjects recorded their estimates of volume by filling in a questionnaire. There was considerable variation in accuracy between subjects. Very large standard deviations were noted, and some subjects were found to over-report, to a maximum of 700%. Nurses were more accurate than doctors (p=0.0003). Nurses' accuracy was influenced by fluid colour but not volume, whereas the opposite was true for doctors. Doctors with more than 20 years' clinical experience significantly overestimated volumes compared to their younger colleagues. This effect was not seen with the nursing group. We conclude that visual estimation is unreliable, and recommend against using visual estimation in clinical practice.

Improving the accuracy of estimated blood loss at obstetric haemorrhage using clinical reconstructions

OBJECTIVES

Following the results of the Confidential Enquiries into Maternal Deaths report, which claims two maternal deaths annually in the UK from postpartum haemorrhage, our aim was to assess the accuracy of 'visual estimation of blood loss' and produce suitable pictorial and written algorithms to aid in the recognition and management of massive obstetric haemorrhage.

DESIGN

Observational study to determine discrepancy between actual blood loss (ABL) and estimated blood loss (EBL).

SETTING

Teaching hospital.

POPULATION

Hundred and three obstetricians, anaesthetists, midwives, nurses and healthcare assistants.

METHODS

Clinical scenarios were reproduced in the form of 12 Objective Structured Clinical Examination (OSCE) style stations augmented with known volumes of whole blood. Individual staff estimated the blood loss visually and recorded their results. Digital photographs were used to produce a pictorial 'algorithm' suitable for use as a teaching tool in labour ward.

MAIN OUTCOME MEASURES

Areas of greatest discrepancy between EBL and ABL.

RESULTS

Significant underestimation of the ABL occurred in 5 of the 12 OSCE stations: 500-ml (50-cm diameter) floor spill, 1000-ml (75-cm diameter) floor spill, 1500-ml (100-cm diameter) floor spill, 350-ml capacity of soaked 45- x 45-cm large swab and the 2-l vaginal postpartum haemorrhage on bed/floor.

CONCLUSIONS

Accurate visual estimation of blood loss is known to facilitate timely resuscitation, minimising the risk of disseminated intravascular coagulation and reducing the severity of haemorrhagic shock. Participation in clinical reconstructions may encourage early diagnosis and prompt treatment of postpartum haemorrhage. Written and pictorial guidelines may help all staff working in labour wards.