Long-Awaited Evidence on Back Blows Versus Abdominal Thrusts.

This is a commentary on the study conducted by Dunne et al. from Alberta, Canada, which retrospectively analyzed data from patients with foreign body airway obstruction (FBAO) in the region. By linking the region's prehospital data with hospital data, the authors were able to report not only the FBAO relief of each intervention, but also patient survival outcomes and complications associated with the interventions. By analyzing the 709 patient encounters that received BLS interventions from bystanders, paramedics, or both, and adjusting for potential confounders, the study showed that abdominal thrusts and chest compressions were associated with decreased odds of FBAO relief compared to back blows as the first intervention. The commentary summarizes the study findings and discusses the importance of the study in the context of FBAO research, which has been choked for too many years.

Effectiveness of the Abdominal Thrust Maneuver for Airway Obstruction Removal: Analysis of Data from the National Emergency Medical Services Information System.

BACKGROUND: Foreign body airway obstruction (FBAO) is a life-threatening emergency. Abdominal thrusts are recommended as first aid, but the success rate for this technique is unclear. Using information from a large database of emergency medical services (EMS) data in the United States, we evaluated the success rate of abdominal thrusts and identified patient characteristics that were associated with the success of the technique. METHODS: A retrospective observational study was conducted using data from the National Emergency Medical Services Information System (NEMSIS) to ascertain the success of abdominal thrusts in patients with FBAO from nearly 14,000 EMS agencies. Success was defined by positive evaluations on subjective and objective EMS criteria. RESULTS: Analysis of 1,947 cases yielded a 46.6% success rate for abdominal thrusts in removing obstructions. The age distribution was bimodal, with peaks during infancy and old age. June had the highest incidence of FBAO. Incidents were most frequent during lunch and dinner times, and most cases occurred in private residences. The first-time success rate was 41.5%, and a lower level of impaired consciousness was associated with lower success rates. A lower incidence of cardiac arrest was noted in successful cases. The success rate was high (60.2%) for children (age ≤15 years), with differences in demographic characteristics and a lower rate of impaired consciousness and cardiac arrests, as compared with unsuccessful interventions in the same age group. CONCLUSIONS: Our study showed a 46.6% success rate for abdominal thrusts in patients with FBAO. The success group had a lower proportion of impaired consciousness and cardiopulmonary arrest than the failure group. Future studies should attempt to identify the most effective maneuvers for clearing airway obstruction.

The effects of bystander interventions for foreign body airway obstruction on survival and neurological outcomes: Findings of the MOCHI registry.

INTRODUCTION: Foreign body airway obstruction (FBAO) is a life-threatening condition. We aimed to quantify the impact of bystander FBAO interventions on survival and neurological outcomes. METHODS: We conducted a Japan-wide prospective, multi-center, observational study including all FBAO patients who presented to the Emergency Department from April 2020 to March 2023. Information on bystander FBAO interventions was collected through interviews with emergency medical services personnel. Primary outcomes included 1-month survival and favorable neurologic outcome defined as Cerebral Performance Category 1 or 2. We performed a multivariable logistic regression and a Cox proportional hazards modeling to adjust for confounders. RESULTS: We analyzed a total of 407 patients in the registry who had the median age of 82 years old (IQR 73-88). The FBAO incidents were often witnessed (86.5%, n = 352/407) and the witnesses intervened in just over half of the cases (54.5%, n = 192/352). The incidents frequently occurred at home (54.3%, n = 221/407) and nursing home (21.6%, n = 88/407). Common first interventions included suction (24.8%, n = 101/407) and back blow (20.9%, n = 85/407). The overall success rate of bystander interventions was 48.4% (n = 93/192). About half (48.2%, n = 196/407) survived to 1-month and 23.8% patients (n = 97/407) had a favorable neurological outcome. Adjusting for pre-specified confounders, bystander interventions were independently associated with survival (hazard ratio, 0.55; 95% CI, 0.39-0.77) and a favorable neurological outcome (adjusted OR, 2.18; 95% CI, 1.23-3.95). CONCLUSION: Bystander interventions were independently associated with survival and favorable neurological outcome, however, they were performed only in the half of patients.

Performance of a Large Language Model on Japanese Emergency Medicine Board Certification Examinations.

BACKGROUND: Emergency physicians need a broad range of knowledge and skills to address critical medical, traumatic, and environmental conditions. Artificial intelligence (AI), including large language models (LLMs), has potential applications in healthcare settings; however, the performance of LLMs in emergency medicine remains unclear. METHODS: To evaluate the reliability of information provided by ChatGPT, an LLM was given the questions set by the Japanese Association of Acute Medicine in its board certification examinations over a period of 5 years (2018-2022) and programmed to answer them twice. Statistical analysis was used to assess agreement of the two responses. RESULTS: The LLM successfully answered 465 of the 475 text-based questions, achieving an overall correct response rate of 62.3%. For questions without images, the rate of correct answers was 65.9%. For questions with images that were not explained to the LLM, the rate of correct answers was only 52.0%. The annual rates of correct answers to questions without images ranged from 56.3% to 78.8%. Accuracy was better for scenario-based questions (69.1%) than for stand-alone questions (62.1%). Agreement between the two responses was substantial (kappa = 0.70). Factual error accounted for 82% of the incorrectly answered questions. CONCLUSION: An LLM performed satisfactorily on an emergency medicine board certification examination in Japanese and without images. However, factual errors in the responses highlight the need for physician oversight when using LLMs.

Effect of prehospital advanced airway management on out-of-hospital cardiac arrest due to asphyxia: A JAAM-OHCA registry-based observational study in Japan.

Aim: To investigate the relationship between prehospital advanced airway management (AAM) and neurological outcomes in patients with asphyxia-related out-of-hospital cardiac arrest (OHCA). Methods: We retrospectively analyzed data from the Japanese Association for Acute Medicine OHCA registry between June 2014 and December 2017. Patients with asphyxia-related cardiac arrest aged ≥18 years were included. The primary outcome was a 1-month favorable neurological outcome (cerebral performance category [CPC] 1-2). Results: Of the 34,754 patients in the 2014-2017 JAAM-OHCA Registry, 1956 were included in our analysis. Cerebral performance category 1-2 was observed in 31 patients (1.6%), while CPC 3-5 was observed in 1925 patients (98.4%). Although prehospital AAM was associated with unfavorable neurological outcomes (odds ratio [OR], 0.269; 95% confidence interval [CI], 0.114-0.633; p = 0.003) in the univariate analysis, the association was not significant in the multivariate analysis. Compared with the AAM group, the non-AAM group showed increased rates of cardiac arrest after emergency medical service contact (4.3 vs. 7.2%, p = 0.009) and Glasgow Coma Scale ≥4 at hospital admission (1.9% vs. 4.7%, p = 0.004). Among the 903 patients for whom the time to return of spontaneous circulation (ROSC) could be calculated, the time from witnessed cardiac arrest to ROSC was significantly shorter (median, 8.5 vs. 37.0 min; p < 0.001) for those with favorable neurological outcomes than for those without. Conclusion: Prehospital AAM is not associated with improved neurological outcomes among those with asphyxia-related OHCA. However, the time from cardiac arrest to the first ROSC was significantly shorter among those with favorable outcomes.

Blood Purification in Patients with Sepsis Associated with Acute Kidney Injury: A Narrative Review.

Sepsis leads to organ dysfunction. Acute kidney injury, a common type of organ dysfunction, is associated with a high mortality rate in patients with sepsis. Kidney replacement therapy can correct the metabolic, electrolyte, and fluid imbalances caused by acute kidney injury. While this therapy can improve outcomes, evidence of its beneficial effects is lacking. Herein, we review the indications for blood purification therapy, including kidney replacement therapy, and the current knowledge regarding acute kidney injury in terms of renal and non-renal indications. While renal indications have been well-documented, indications for blood purification therapy in sepsis (non-renal indications) remain controversial. Excessive inflammation is an important factor in the development of sepsis; blood purification therapy has been shown to reduce inflammatory mediators and improve hemodynamic instability. Given the pathophysiology of sepsis, blood purification therapy may decrease mortality rates in these patients. Further trials are needed in order to establish the effectiveness of blood purification therapy for sepsis.

Ventilator management and risk of air leak syndrome in patients with SARS-CoV-2 pneumonia: a single-center, retrospective, observational study.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia is reportedly associated with air leak syndrome (ALS), including mediastinal emphysema and pneumothorax, and has a high mortality rate. In this study, we compared values obtained every minute from ventilators to clarify the relationship between ventilator management and risk of developing ALS. METHODS: This single-center, retrospective, observational study was conducted at a tertiary care hospital in Tokyo, Japan, over a 21-month period. Information on patient background, ventilator data, and outcomes was collected from adult patients with SARS-CoV-2 pneumonia on ventilator management. Patients who developed ALS within 30 days of ventilator management initiation (ALS group) were compared with those who did not (non-ALS group). RESULTS: Of the 105 patients, 14 (13%) developed ALS. The median positive-end expiratory pressure (PEEP) difference was 0.20 cmH2O (95% confidence interval [CI], 0.20-0.20) and it was higher in the ALS group than in the non-ALS group (9.6 [7.8-20.2] vs. 9.3 [7.3-10.2], respectively). For peak pressure, the median difference was -0.30 cmH2O (95% CI, -0.30 - -0.20) (20.4 [17.0-24.4] in the ALS group vs. 20.9 [16.7-24.6] in the non-ALS group). The mean pressure difference of 0.0 cmH2O (95% CI, 0.0-0.0) (12.7 [10.9-14.6] vs. 13.0 [10.3-15.0], respectively) was also higher in the non-ALS group than in the ALS group. The difference in single ventilation volume per ideal body weight was 0.71 mL/kg (95% CI, 0.70-0.72) (8.17 [6.79-9.54] vs. 7.43 [6.03-8.81], respectively), and the difference in dynamic lung compliance was 8.27 mL/cmH2O (95% CI, 12.76-21.95) (43.8 [28.2-68.8] vs. 35.7 [26.5-41.5], respectively); both were higher in the ALS group than in the non-ALS group. CONCLUSIONS: There was no association between higher ventilator pressures and the development of ALS. The ALS group had higher dynamic lung compliance and tidal volumes than the non-ALS group, which may indicate a pulmonary contribution to ALS. Ventilator management that limits tidal volume may prevent ALS development.

Cerebral edema associated with diabetic ketoacidosis: Two case reports.

Background: Diabetic ketoacidosis (DKA) is associated with a high mortality rate, especially if cerebral edema develops during the disease course. It is rarer and more severe in adults than in children. We present cases of two patients with cerebral edema-related DKA. Case presentation: The first patient was a 38-year-old man with diabetes mellitus who presented with DKA-related disturbed consciousness. Although glycemic correction was performed slowly, he showed pupil dilation 11 h later. He underwent emergency ventricular drainage, but died of cerebral herniation. The second patient was a 25-year-old woman who presented with impaired consciousness secondary to DKA. Head computed tomography showed subarachnoid hemorrhage and cerebral edema. No related intraoperative findings were observed; it was concluded that the first computed tomography scan revealed pseudo-subarachnoid hemorrhage. Conclusion: Diabetic ketoacidosis-related cerebral edema develops despite treatment according to guidelines and is difficult to predict. Therefore, adult patients should be treated cautiously during DKA management.

Heat stroke management during the COVID-19 pandemic: Recommendations from the experts in Japan (2nd edition).

Both coronavirus disease 2019 (COVID-19) and heat stroke have symptoms of fever or hyperthermia and the difficulty in distinguishing them could lead to a strain on emergency medical care. To mitigate the potential confusion that could arise from actions for preventing both COVID-19 spread and heat stroke, particularly in the context of record-breaking summer season temperatures, this work offers new knowledge and evidence that address concerns regarding indoor ventilation and indoor temperatures, mask wearing and heat stroke risk, and the isolation of older adults. Specifically, the current work is the second edition to the previously published guidance for handling heat stroke during the COVID-19 pandemic, prepared by the "Working group on heat stroke medical care during the COVID-19 epidemic," composed of members from four organizations in different medical and related fields. The group was established by the Japanese Association for Acute Medicine Heatstroke and Hypothermia Surveillance Committee. This second edition includes new knowledge, and conventional evidence gleaned from a primary selection of 60 articles from MEDLINE, one article from Cochrane, 13 articles from Ichushi, and a secondary/final selection of 56 articles. This work summarizes the contents that have been clarified in the prevention and treatment of infectious diseases and heat stroke to provide guidance for the prevention, diagnosis, and treatment of heat stroke during the COVID-19 pandemic.

Food choking incidents in the hospital: Incidents, characteristics, effectiveness of interventions, and mortality and morbidity outcomes.

AIM: Foreign body airway obstruction (FBAO) due to food can occur wherever people eat, including in hospitals. We characterized in-hospital FBAO incidents and their outcomes. METHODS: We searched the Japan Council for Quality Health Care nationwide in-hospital adverse events database for relevant events from 1,549 institutions. We included all patients with FBAO incidents due to food in the hospital from January 2010 to June 2021 and collected data on the characteristics, interventions, and outcomes. FBAO from non-food materials were excluded. Our primary outcomes were mortality and morbidity from FBAO incidents. RESULTS: We identified 300 patients who had a FBAO incident from food. The most common age group was 80-89 years old (32.3%, n = 97/300). One-half (50.0%, n = 150/300) were witnessed events. Suction was the most common first intervention (31.3%, n = 94/300) and resulted in successful removal of foreign body in 17.0% of cases (n = 16/94). Back blows (16.0%, n = 48/300) and abdominal thrusts (8.1%, n = 24/300) were less frequently performed as the first intervention and the success rates were 10.4% (n = 5/48) and 20.8% (n = 5/24), respectively. About one-third of the patients (31%, n = 93/300) died and 26.7% (n = 80/300) had a high potential of residual disability from these incidents. CONCLUSION: FBAO from food in the hospital is an uncommon but life-threatening event. The majority of patients who suffered from in-hospital FBAO incidents did not receive effective interventions initially and many of them died or suffered residual disability.

An unbroken ring of the chain of survival.

This is a commentary on the study conducted by Kennedy et al. from Victoria, Australia, that analyzed the cohort of all adult EMS-witnessed out-of-hospital cardiac arrest (OHCA) patients in the region and compared patients treated during the COVID-19 period to a historical comparator period. The commentary summarizes the study findings and discusses the importance of the study in the context of the chain of survival and changes in airway management for OHCA patients during the COVID-19 pandemic.

Rapidly progressive cerebral atrophy following a posterior cranial fossa stroke: Assessment with semiautomatic CT volumetry.

BACKGROUND: The effect of posterior cranial fossa stroke on changes in cerebral volume is not known. We assessed cerebral volume changes in patients with acute posterior fossa stroke using CT scans, and looked for risk factors for cerebral atrophy. METHODS: Patients with cerebellar or brainstem hemorrhage/infarction admitted to the ICU, and who underwent at least two subsequent inpatient head CT scans during hospitalization were included (n = 60). The cerebral volume was estimated using an automatic segmentation method. Patients with cerebral volume reduction > 0% from the first to the last scan were defined as the "cerebral atrophy group (n = 47)," and those with ≤ 0% were defined as the "no cerebral atrophy group (n = 13)." RESULTS: The cerebral atrophy group showed a significant decrease in cerebral volume (first CT scan: 0.974 ± 0.109 L vs. last CT scan: 0.927 ± 0.104 L, P < 0.001). The mean percentage change in cerebral volume between CT scans in the cerebral atrophy group was -4.7%, equivalent to a cerebral volume of 46.8 cm3, over a median of 17 days. The proportions of cases with a history of hypertension, diabetes mellitus, and median time on mechanical ventilation were significantly higher in the cerebral atrophy group than in the no cerebral atrophy group. CONCLUSIONS: Many ICU patients with posterior cranial fossa stroke showed signs of cerebral atrophy. Those with rapidly progressive cerebral atrophy were more likely to have a history of hypertension or diabetes mellitus and required prolonged ventilation.

Effects of Changes in Body Fat Mass as a Result of Regular Exercise on Hemoglobin A1c in Patients With Type 2 Diabetes Mellitus: A Meta-Analysis.

An increase in visceral fat is associated with an increase in insulin resistance, so reducing body fat mass through exercise may help alleviate type 2 diabetes mellitus (T2DM). The current meta-analysis evaluated the effect of changes in body fat via an intervention of regular exercise on hemoglobin A1c (HbA1c) in patients with T2DM. The inclusion criteria were randomized controlled trials involving adults with T2DM, intervention involving exercise alone, an overall duration of intervention ≥12 weeks, and reporting HbA1c and body fat mass. The mean differences (MDs) were defined as the MD between the exercise group and the control group, and the MDs in HbA1c (in percentage) and body fat mass (in kilograms) were calculated. All MDs in HbA1c were pooled as overall effects. A meta-regression analysis was performed to evaluate the relationship between the MD in the body fat mass (in kilograms) and the MD in HbA1c. Twenty studies (1,134 subjects) were analyzed. The pooled MD in HbA1c (in percentage) decreased significantly (-0.4; 95% confidence interval [-0.5, -0.3]) but contained significant heterogeneity (Q = 52.7, p < .01; I2 = 41.6%). A meta-regression analysis showed that a decrease in the MD in body fat mass was significantly associated with a decrease in the MD in HbA1c (R2 = 80.0%) and heterogeneity decreased (Q = 27.3, p = .61; I2 = 11.9%), and a reduction in body fat mass of 1 kg was estimated to decrease the HbA1c (%) by approximately 0.2. The current study suggested that a decrease in HbA1c due to regular exercise depends on a reduction in body fat mass in patients with T2DM.

Characteristics and Outcomes of Emergency Transferred Patients with Foreign Body Airway Obstruction in Tokyo, Japan.

INTRODUCTION: Foreign body airway obstruction (FBAO) is a life-threatening emergency, and the prognosis of patients with FBAO is greatly affected by the prehospital process. There are only a few large-scale studies analyzing prehospital process databases of the fire department. STUDY OBJECTIVE: The aim of this study was to investigate whether characteristics of patients with FBAO were associated with prehospital factors and outcomes. METHODS: In this retrospective observational study, patients transferred to the hospital by the Tokyo, Japan Fire Department for FBAO from 2017 through 2019 were included. The association between neurologically favorable survival among the characteristics of patients with FBAO and prehospital factors affecting the outcomes was evaluated. RESULTS: Of the 2,429,175 patients, 3,807 (0.2%) patients had FBAO. The highest number of FBAO cases was 99 (2.6%), which occurred on January 1 (New Year's Day), followed by 40 cases (1.1%) on January 2, and 28 cases (0.7%) on January 3. The number of patients who experienced out-of-hospital cardiac arrest (OHCA) caused by FBAO was 1,644 (43.2%). Comparing the OHCA and non-OHCA groups, there were significant differences in age, sex, time spent at the site, and distance between the site and hospital. Cardiac arrest was significantly lower in infants after FBAO (P < .001). In total, 98.2% of patients who did not have return of spontaneous circulation (ROSC) before hospital arrival died within 30 days, a significantly higher mortality rate than that in patients who had ROSC (98.2% versus 65.8%; P < .001). CONCLUSIONS: Among patients who did not have ROSC following FBAO upon arrival at the hospital, 98.2% died within 30 days. Thus, it is important to remove foreign bodies promptly and provide sufficient ventilation to the patient at the scene to increase the potential for ROSC. Further, more precautions should be exercised to prevent FBAO at the beginning of the year.

Development of a Machine Learning Model to Predict Cardiac Arrest during Transport of Trauma Patients.

BACKGROUND: Trauma is a serious medical and economic burden worldwide, and patients with traumatic injuries have a poor survival rate after cardiac arrest. The authors developed a prediction model specific to prehospital trauma care and used machine learning techniques to increase its accuracy. METHODS: This retrospective observational study analyzed data from patients with blunt trauma injuries due to traffic accidents and falls from January 1, 2018, to December 31, 2019. The data were collected from the National Emergency Medical Services Information System, which stores emergency medical service activity records nationwide in the United States. A random forest algorithm was used to develop a machine learning model. RESULTS: The prediction model had an area under the curve of 0.95 and a negative predictive value of 0.99. The feature importance of the predictive model was highest for the AVPU (Alert, Verbal, Pain, Unresponsive) scale, followed by oxygen saturation (SpO2). Among patients who were progressing to cardiac arrest, the cutoff value was 89% for SpO2 in nonalert patients. CONCLUSIONS: The machine learning model was highly accurate in identifying patients who did not develop cardiac arrest.

Effects of Differences in Exercise Programs With Regular Resistance Training on Resting Blood Pressure in Hypertensive Adults: A Systematic Review and Meta-Analysis.

ABSTRACT: Igarashi, Y. Effects of differences in exercise programs with regular resistance training on resting blood pressure in hypertensive adults: A systematic review and meta-analysis. J Strength Cond Res 37(1): 253-263, 2023-This systematic review and meta-analysis aimed to evaluate changes in resting blood pressure (RBP) with differences in regular resistance training (RT) programs. Inclusion criteria were randomized controlled trials involving hypertensive adults and interventions involving only RT of both the upper and lower limbs for ≥7 weeks. The weighted mean difference (WMD) was defined as the mean difference between the exercise and control groups, weighted by the inverse of the squared standard error for each study, and all WMDs in RBP were pooled as overall effects. A simple meta-regression analysis was performed to evaluate the relationship between RT variables (percentage 1 repetition maximum [1RM], number of repetitions, number of sets, and weekly frequency) and changes in RBP. Seventeen studies (646 subjects) were analyzed. The pooled WMDs in the resting systolic blood pressure (RSBP) and resting diastolic blood pressure (RDBP) decreased significantly but contained significant heterogeneity {RSBP, -4.7 mm Hg (95% confidence interval [CI], -6.7 to -2.8; I2 = 46.6%); RDBP, -3.5 mm Hg (95% CI, -4.9 to -2.1; I2 = 39.1%)}. Meta-regression analysis revealed that an increase in % 1RM was significantly associated with a decrease in the RSBP (γ = -0.25x 0 + 10.85, where γ represents the mean difference in RSBP, and x 0 represents % 1RM [%]), and heterogeneity was alleviated ( I2 = 0.0%). For reducing RSBP, regular RT with moderate or heavy loads may be more beneficial than regular RT with light loads.

Do Video Calls Improve Dispatcher-Assisted First Aid for Infants with Foreign Body Airway Obstruction? A Randomized Controlled Trial/Simulation Study.

BACKGROUND: Because choking quickly leads to cardiopulmonary arrest, it is crucial that bystanders remove foreign bodies effectively. Although oral instructions in video calls by dispatchers have improved the quality of cardiopulmonary resuscitation, it is unclear whether video calls improve the quality of first aid for choking infants. Therefore, this simulation study aimed to determine whether video calls with dispatchers improve the quality of first aid for infants with foreign body airway obstruction (FBAO). METHODS: Seventy first-year college students randomly assigned in pairs to communicate by video or audio calls participated in simulated emergency calls for infants with FBAO. Both groups began with oral instruction in voice calls until the transition was made to video calls in the video group. The primary outcome was quality of first aid performance, which was categorized as excellent, acceptable, or poor on the basis of existing guidelines. RESULTS: There were 17 simulations in the video-call groups and 16 in the voice-call groups. After initial oral instruction, the proportion of rescuers that received an evaluation of excellent or acceptable did not differ significantly between the groups (video, 41% vs. voice, 50%; P=0.61); however, evaluations for seven rescuers improved after transitioning to video calls. Ultimately, the proportion receiving a poor evaluation was significantly lower in the video-call group than in the voice-call group (50% vs. 82%, P=0.049). CONCLUSION: Oral instruction communicated by video calls improved the quality of first aid for infants with FBAO.

Trends in the number of patients from traffic accidents and the state of emergency.

Aim: During the coronavirus disease 2019 pandemic, the number of traffic accidents and injured patients was reported to be lower than that before the pandemic. However, little is known regarding the relationship between periods of the state of emergency and the number of patients who met with traffic accidents. Methods: The numbers of trauma patients and deaths due to traffic accidents in Tokyo and Osaka were collected monthly from the statistics published by the police department. A state of emergency was declared four times in both cities. The number of trauma patients and deaths was compared between the emergency and other periods. Results: The number of monthly patients per 100,000 due to traffic accidents during the state of emergency was significantly lower than that during other periods in Tokyo (16.56 versus 18.20; P = 0.008) and Osaka (24.12 versus 28.79; P = 0.002). However, the monthly number of deaths during the state of emergency was not significantly different compared with those during the other periods in Tokyo (0.08 versus 0.08; P = 0.65) and Osaka (0.10 versus 0.14; P = 0.082). A decrease in the number of trauma patients was observed before the emergency period; however, the reduction rate dropped as the period passed. Conclusion: There were significantly fewer trauma patients due to traffic accidents during the state of emergency than during the other periods, with no significant difference in the number of deaths.