Comparing outcomes of coronary artery bypass surgery: Is the New York Cardiac Surgery Reporting System model sensitive to changes in case mix?

OBJECTIVE: To assess the validity of using the standardized mortality ratio (SMR), based on the New York State Cardiac Surgery Reporting System (CSRS) prediction model to compare coronary artery bypass grafting (CABG) outcomes between hospitals. DESIGN: The study was designed as a retrospective study based on a database containing all patients undergoing isolated CABG surgery in New York State hospitals in 1996 (n = 20,078). In the first part of this study, a computer simulation was used to assess the impact of case mix variation on the SMR. A computer-intensive algorithm was used to create 5,000 random case mixes from the patients in the CSRS database. The SMR associated with each of the 5,000 case mixes was calculated using a resampling algorithm. The second part of this study was designed to determine whether the identity of quality outliers among all of the 32 hospitals in the CSRS database would change after adjusting for the effects of case mix on the SMR. The SMR associated with the case mix of each hospital in the CSRS database (the hospital case mix SMR) was obtained using a resampling algorithm. The hospital SMR (as well as 95% confidence interval) was then calculated using bootstrapping for each of the 32 hospitals within the CSRS database. An adjusted SMR was then derived for each hospital by dividing the hospital SMR by the case mix SMR for that hospital. SETTING: Thirty-two hospitals in New York State performing CABG surgery. INTERVENTIONS: None. RESULTS: Changes in patient case mix are associated with statistically significant changes in the SMR. However, there was no difference in the identity of quality outliers in the New York State CSRS database when using either the SMR or the SMR adjusted for the effects of case mix. CONCLUSION: Risk-adjusted measures of outcomes in CABG patients may be potentially biased by differences in case mix between institutions because of the influence of case mix on the process of risk adjustment. There was, however, no evidence of bias in the specific application of the CSRS model to the hospitals in the CSRS database.

Chest radiographs of limited utility in the diagnosis of blunt traumatic aortic laceration.

BACKGROUND: The radiographic diagnosis of blunt traumatic aortic laceration (BTAL) remains problematic. We reviewed our experience with chest radiographic signs of BTAL at a single trauma center. METHODS: The chest radiographs of 188 consecutive blunt trauma patients with suspected BTAL who underwent portable chest radiography and aortography were retrospectively reviewed by a thoracic radiologist. The presence or absence of 15 radiographic findings were recorded, and the sensitivity and specificity of individual radiographic signs and combinations of signs were determined. RESULTS: There were 10 patients with BTAL. Although three signs showed greater than 90% sensitivity for BTAL, these signs showed low specificity, and no significant improvement in overall accuracy was achieved by combining radiographic findings. CONCLUSION: The experience at our institution suggests that chest radiographs have limited utility in the accurate diagnosis of blunt traumatic aortic laceration. Cross-sectional imaging techniques will likely become the preferred imaging procedures for evaluating patients with suspected BTAL.

A population-based study of geriatric trauma in a rural state.

BACKGROUND: Urban geriatric trauma patients are known to die more often than their younger counterparts. Little is known of the fate of geriatric trauma patients in a rural environment where delays to definitive treatment are frequent. We hypothesized that rural trauma patients would do worse than their urban counterparts because of prolonged delays to definitive care. METHODS: Five-year retrospective analysis of all trauma deaths occurring within a rural state and retrospective outcome analysis of trauma patients admitted to a tertiary care facility who were less than 55 years old (defined as young) and 55 or more years old (defined as old). Outcome analysis was performed comparing old and young rural hospitalized patients to the Major Trauma Outcome Study data set collected in major urban trauma centers. RESULTS: Of the total trauma deaths in the state, 32.5% were old. Old patients were less likely to die at the scene of the injury than were their younger counterparts (R2 = 0.84, p < 0.001). Hospitalized old patients had a significantly higher mean Revised Trauma Score and a significantly lower Injury Severity Score, a higher complication rate, and a higher mortality rate than did hospitalized young patients. The young group had a significantly better survival (W = 0.59, Z = -3.49, p = 0.0001) than the MTOS data set, but the old group had a significantly worse survival (W = -1.8, Z = -3.49, p = 0.001). CONCLUSION: In a rural environment, old trauma patients die more commonly in the hospital than their younger counterparts, who die more commonly at the scene. Old trauma patients who die in the hospital were less severely injured than their younger counterparts who died in the hospital. Old patients admitted to this rural trauma center have a significantly worse survival than their urban counterparts despite the fact that young rural trauma patients do significantly better than their urban counterparts. Understanding the demographics of rural geriatric trauma may be useful in allocating resources in rural trauma system design. It must be understood that despite relatively low injury severity and physiologic stability, there is a significant potential for rural geriatric trauma patients to do poorly.

Population-based study of hospital trauma care in a rural state without a formal trauma system.

OBJECTIVE: Formalized systems of trauma care are believed to improve outcomes in an urban setting, but little is known of the applicability in a rural setting. METHODS: We conducted a population-based analysis of hospital survival after trauma comparing an American College of Surgeons-verified Level I trauma center (TC) with the pooled results of 13 small community hospitals (CH) in a rural state with no formal trauma system. All patients admitted to any hospital within the state of Vermont over a 5-year period (1995-1999) with a trauma discharge diagnosis were included. Elderly patients with isolated femur fractures were excluded from the database. International Classification of Diseases Injury Severity Scores (ICISSs) were calculated for each patient and used to control for injury severity in an omnibus logistic regression model that included age, ICISS, and hospital type (TC vs. CH) as predictors of survival. Patients who died were characterized on the basis of ICISS into "expected" (ICISS < 0.25), "indeterminate" (ICISS = 0.26-0.50), and "unexpected" (ICISS > 0.5). RESULTS: In 16,354 trauma admissions over the 5-year period in the rural state of Vermont, 370 (2.2%) died. There were 5,964 (36%) admitted to TC. Patients admitted to TC were more injured (ICISS 0.94 vs. 0.96) and had a higher mortality (3.1% vs. 1.8). Overall, care at the CH provided an improved survival (odds ratio = 1.75, 95% confidence internal = 1.31-2.18, p = 0.000). However, in the more severely injured cohort of trauma patients (expected and indeterminate; n = 133), overall survival was higher in the TC (16% CH vs. 38% TC, p = 0.02, chi2). Because the TC was known to provide care equivalent to Major Trauma Outcome Study norms during this time period (Z = -0.03, M = 0.894), we believe this study confirms that trauma care throughout the state is in accordance with national norms. CONCLUSION: In a rural state, without a statewide formal trauma system, survival after trauma is no worse at CH than TC when corrected for injury severity and age. Future expenditures of resources might better be concentrated in other areas such as discovery or prehospital care to further improve outcomes.

Do pediatric trauma centers have better survival rates than adult trauma centers? An examination of the National Pediatric Trauma Registry.

BACKGROUND: Pediatric trauma centers (PTCs) were developed to improve the survival of injured children, but it is currently unknown if children admitted to PTCs are more likely to survive than those admitted to adult trauma centers (ATCs). METHODS: Fifty-three thousand one hundred thirteen pediatric trauma cases from 22 PTCs and 31 ATCs included in the National Pediatric Trauma Registry were reviewed to evaluate survival rates at PTCs and ATCs. RESULTS: Overall, 1,259 children died. The raw mortality rate was lower at PTCs (1.81% of 32,554 children) than at ATCs (3.88% of 18,368 children). However, patients admitted to ATCs were more severely injured. When Injury Severity Score, Pediatric Trauma Score, mechanism (blunt or penetrating), gender, age, clustering, and American College of Surgeons (ACS) verification status were controlled for using a single logistic regression model, there was no statistically significant difference in survival between PTCs and ATCs (odds ratio, 1.02; 95% confidence interval, 0.83-1.26; p = 0.587). A similar comparison of the 12 ACS-verified trauma centers with the 41 nonverified centers showed verification to be associated with improved survival (odds ratio, 0.75; 95% confidence interval, 0.58-0.97; p = 0.013). CONCLUSION: Although PTCs have higher overall survival rates than ATCs, this difference disappears when the analysis controls for Injury Severity Score, Pediatric Trauma Score, age, mechanism, and ACS verification status. ACS-verified centers have significantly higher survival rates than do unverified centers.

Effect of mortality rate on the performance of the Acute Physiology and Chronic Health Evaluation II: a simulation study.

OBJECTIVE: To evaluate the impact of case mix variation on the performance of the Acute Physiology and Chronic Health Evaluation (APACHE) II using measures of calibration and discrimination. DESIGN: APACHE II data were collected prospectively at the surgical intensive care unit of the University of Vermont on all adult admissions over an 8-yr period (excluding cardiac surgical patients, burn patients, and patients < 16 yrs of age). The original case mix was systematically varied to create 2,000 different case mixes ranging in mortality between 5% and 18% using a computer-intensive resampling algorithm. The area under the receiver operating characteristic curve and the Hosmer-Lemeshow C statistic were derived for each of the simulated case mixes with bootstrapping. SETTING: The surgical intensive care unit at a 450-bed teaching hospital. PATIENTS: A group of 6,806 adult surgical patients excluding cardiac surgical patients and burn patients. MEASUREMENTS AND RESULTS: Simulated data sets were created from a database of patients treated at a single institution to test the hypothesis that the performance of APACHE II is stable across a clinically reasonable range of mortality rates. The discrimination and calibration of APACHE II varied with case mix. CONCLUSION: The discrimination of APACHE II is not independent of case mix. However, the variability of the Hosmer-Lemeshow statistic as a function of the case mix may simply reflect the limitations of this goodness of fit statistic to assess model calibration. Because the discrimination of APACHE II is a function of case mix, caution should be exercised when using APACHE II-based adjusted mortality rates to compare intensive care units with widely divergent case mixes.

Nonoperative management of hepatic, splenic, and renal injuries in adults with multiple injuries.

BACKGROUND: Nonoperative management (NOM) of abdominal solid organ (ASO; liver, spleen, kidney) injuries from blunt trauma in adults has gained acceptance, but multisystem trauma remains a relative contraindication to NOM. METHODS: We reviewed the charts of 126 adult patients who underwent NOM of an ASO injury for success of NOM, transfusions, and complications. Patients were divided into two groups: group I had isolated ASO injuries (n = 48); group II had an ASO injury and at least one additional injury with an Abbreviated Injury Score > or = 2 (n = 78). RESULTS: NOM was successful 89.6% of group I and 93.6% of group II patients (p = 0.55). Group II had higher Injury Severity Scores (20.7 +/- 9.8 vs. 8.3 +/- 4.9 p < 0.05) and transfusion requirements (30.8% vs. 14.6%,p < 0.05) than group I. Complication rates were not different (group I, 20.8% vs. 26.9% group II, p = 0.58). CONCLUSION: NOM of ASO injuries may attempted in adult patients with multiple injuries without increased morbidity.

A multi-institutional study of factors associated with fetal death in injured pregnant patients.

HYPOTHESIS: Factors associated with fetal death in injured pregnant patients are related to increasing injury severity and abnormal maternal physiologic profile. DESIGN: A multi-institutional retrospective study of 13 level I and level II trauma centers from 1992 to 1996. MAIN OUTCOME MEASURE: Fetal survival. RESULTS: Of 27,715 female admissions, there were 372 injured pregnant patients (1.3%); 84% had blunt injuries and 16% had penetrating injuries. There were 14 maternal deaths (3.8%) and 35 fetal deaths (9.4%). The population suffering fetal death had higher injury severity scores (P<.001), lower Glascow Coma Scale scores (P<.001), and lower admitting maternal pH (P = .002). Most women who lost their fetus arrived in shock (P = .005) or had a fetal heart rate of less than 110 beats/min at some time during their hospitalization (P<.001). An Injury Severity Score greater than 25 was associated with a 50% incidence of fetal death. Placental abruption was the most frequent complication, occurring in 3.5% of patients and associated with 54% mortality. Cardiotrophic monitoring to detect potentially threatening fetal heart rates was performed on only 61% of pregnant women in their third trimester. Of these patients, 7 had abnormalities on cardiotrophic monitoring and underwent successful cesarean delivery. CONCLUSIONS: Fetal death was more likely with greater severity of injury. Cardiotrophic monitoring is underused in injured pregnant patients in their third trimester even after admission to major trauma centers. Increased use of cardiotrophic monitoring may decrease the mortality caused by placental abruption.

Rural trauma: the challenge for the next decade.

Improving the care of trauma patients in a rural environment requires that several important issues be addressed. First, a universal definition of what constitutes "rural" must be established. We propose that a combined effort of the Federal Government and the Committee on Trauma of the American College of Surgeons develop this definition. Second, data on rural trauma demographics and outcome must be collected in a national database. We propose that this database be incorporated in the "TRACS" database of the Committee on Trauma of the American College of Surgeons. Such a database will allow a "needs assessment analysis of existing care in rural environments and facilitate planning and implementation of efficient systems of care. Funding for the rural database should come from the federal government. Finally, increased public awareness of problems unique to rural trauma care is necessary. The rural trauma subcommittee of the ACSCOT should go from an ad hoc committee to a standing committee with the American College of Surgeons Committee on Trauma. We propose a national conference on rural trauma care hosted by the federal government for the purpose of addressing these issues and simultaneously increasing public awareness.

Focused abdominal sonogram for trauma: the learning curve of nonradiologist clinicians in detecting hemoperitoneum.

BACKGROUND: The focused abdominal sonogram for trauma (FAST) has been used by surgeons and emergency physicians (CLIN) to screen reliably for hemoperitoneum after trauma. Despite recommendations for "appropriate training," ranging from 50 to 400 proctored examinations, there are no supporting data. METHODS: We prospectively examined the initial FAST experience of CLIN in detecting hemoperitoneum by using diagnostic peritoneal lavage, computed tomography, and clinical findings as the diagnostic "gold standard." RESULTS: 241 patients had FAST performed by 12 CLIN (average, 20/CLIN; range, 2-43); 51 patients (21.2%) had hemoperitoneum and 17 patients (7.1%) required laparotomy. Initial experience with FAST by CLIN produced 35 true positives, 180 true negatives, 16 false negatives, and 3 false positives; sensitivity, 68%; specificity, 98%. Initial error rate was 17%, which fell to 5% after 10 examinations (chi2; p < 0.05). CONCLUSION: Previous recommendations for the number of proctored examinations for individual nonradiologist clinician sonographers to develop competence are excessive.

Computed tomographic angiography as a screening modality for blunt cervical arterial injuries: preliminary results.

BACKGROUND: The diagnosis of blunt cervical arterial injury (CAI) is made difficult by its infrequent occurrence and delayed presentation. Beginning in January of 1995, we used computed tomographic angiography (CTA) of the neck to screen for CAI. We hypothesized that CTA could be incorporated into the workup of patients sustaining blunt neck injury as a screening modality for CAI and that CTA would increase the early detection of CAI. METHODS: Retrospective review of all CAI for the years January of 1988 to June of 1997 at a Level I trauma center. CAI diagnosed before introduction of CTA (pre-CTA; January of 1988 to December of 1994) were compared with those after (post-CTA; January of 1995 to June of 1997). RESULTS: The overall incidence of CAI for the entire time period was 0.11%. Motor vehicle crash (53%) was the most common mechanism, with focal neurologic deficit (23%) or seizures (17.6%) the most common presenting clinical symptoms. CTA added only a few additional minutes to the time required for the workup of patients sustaining blunt neck injury in whom CAI was suspected. The incidence of CAI increased from 0.06% pre-CTA to 0.19% post-CTA (p = 0.02; Fisher exact test). CTA was associated with a decrease in mean time to make the diagnosis of CAI (156 hours pre-CTA vs. 5.9 hours post-CTA). In addition, CTA was associated with a decrease in the incidence of permanent neurologic sequelae from CAI (50% pre-CTA vs. 0% post-CTA; p = 0.07; Fisher exact test). CONCLUSION: We conclude that CTA does not significantly increase the time of the diagnostic workup of the patient with injuries caused by blunt trauma. The introduction of CTA at our institution was associated with an increase in the detection rate of CAI. Earlier detection of CAI may allow for more timely therapeutic intervention and potentially prevent permanent neurologic sequelae.

Financial aspects of providing trauma care at the extremes of life.

BACKGROUND: Children and the elderly are more likely to be underinsured compared with the general population of trauma patients. We performed financial analysis on all trauma patients admitted during an 18-month period to a Level I adult and pediatric trauma center to evaluate the financial impact of providing trauma care for children and the elderly. METHODS: Patients were categorized by age: PEDI<17 years, GERI>64 years and MID = 17 to 64 years. Reimbursement ratio (RR = reimbursement/cost; RR>1 = profit, RR<1 = loss), length of stay (LOS), and Injury Severity Score (ISS) were calculated for each age group. RESULTS: RR for GERI (RR = 0.99) was significantly lower than for PEDI (RR = 1.15) and MID (RR = 1.16). There was no difference in ISS, but the LOS of GERI was greater than that of PEDI and MID (p<0.05). Cost per patient and LOS were less in PEDI versus MID and GERI (p<0.05). CONCLUSION: Trauma care reimbursement for the elderly is inadequate, whereas pediatric trauma care costs less to deliver and is profitable to the trauma center.

Study of the outcome of patients transferred to a level I hospital after stabilization at an outlying hospital in a rural setting.

OBJECTIVE: To determine the characteristics and outcome of transferred trauma patients in a rural setting. METHODS: We conducted a case-control study of all trauma admissions to a rural Level I trauma center to examine a 3.5-year (1993-1996) comparison of trauma patients admitted directly with those transferred (RTTP) after being initially stabilized at an outlying hospital. We used prehospital times, Injury Severity Score (ISS), LD50ISS (the ISS at which 50% of patients died), Revised Trauma Score, probability of survival, Acute Physiology and Chronic Health Evaluation II, and observed survival as main outcome measures. RESULTS: RTTPs (39.4%) spent an average of 182+/-139 minutes at the outlying hospital and 72+/-42 minutes in transport to the trauma center. Proportionately more head/neck and patients with multiple injuries composed the RTTP group. The RTTP were more severely injured (ISS 11.1+/-8.5; Acute Physiology and Chronic Health Evaluation II 16.2+/-5.8; Revised Trauma Score 7.44+/-1.1) than the trauma patients admitted directly (ISS 7.9+/-5.3; Acute Physiology and Chronic Health Evaluation II 13.1+/-6.3; Revised Trauma Score 7.8+/-0.4; p < 0.05). However, both groups had the same LD50ISS (ISS = 35). When logistic regression was applied with death as the dependent variable, both ISS and age contributed significantly (p = 0.0001) but transfer status did not (p = 0.473). CONCLUSION: Rural trauma centers admit a high percentage of RTTP. These RTTP have a higher injury severity and acuity than their trauma patients admitted directly counterparts. Trauma care in rural areas that involves initial stabilization at outlying hospitals does not adversely affect mortality.

Predicting survival, length of stay, and cost in the surgical intensive care unit: APACHE II versus ICISS.

BACKGROUND: Risk stratification of patients in the intensive care unit (ICU) is an important tool because it permits comparison of patient populations for research and quality control. Unfortunately, currently available scoring systems were developed primarily in medical ICUs and have only mediocre performance in surgical ICUs. Moreover, they are very expensive to purchase and use. We conceived a simple risk-stratification tool for the surgical ICU that uses readily available International Classification of Diseases, Ninth Revision, codes to predict outcome. Called ICISS (International Classification of Disease Illness Severity Score), our score is the product of the survival risk ratios (obtained from an independent data set) for all International Classification of Diseases, Ninth Revision, diagnosis codes. METHODS: A total of 5,322 noncardiac patients admitted to a surgical ICU during an 8-year period had their Acute Physiology and Chronic Health Evaluation (APACHE) II scores compared with their ICISS as predictors of outcome (survival/nonsurvival, length of stay, and charges). RESULTS: ICISS proved to be a much better predictor of survival than APACHE (receiver operating characteristic (ROC) APACHE = 0.806; Hosmer-Lemeshow (HL) APACHE = 22.56; ROC ICISS = 0.892; HL ICISS = 12.06) or the APACHE survival probability (ROC = 0.836; HL = 34.47). These differences were highly statistically significant (p < 0.001). ICISS was also better correlated with ICU length of stay (APACHE R2 = 0.06; ICISS R2 = 0.32) and ICU charges (APACHE R2 = 0.07; ICISS R2 = 0.39). When combined in a logistic model with ICISS, APACHE II added slightly to the predictive power of ICISS alone (combined ROC = 0.903) but degraded the calibration of the model (combined HL = 16.29; p = 0.038). CONCLUSION: Because ICISS is both more accurate and much less expensive to calculate than APACHE II score, ICISS should replace APACHE II score as the standard risk stratification tool in surgical ICUs.

Elevated pancreatic enzymes after extended propofol therapy.

Propofol is a sedative hypnotic agent often administered for intensive care sedation. A 28-year-old man who suffered a severe head injury developed elevated pancreatic enzymes after receiving extended high-dosage propofol therapy. Amylase and lipase values gradually reduced toward normal after the drug was discontinued. Possible propofol-induced pancreatitis was reported with short-term but not with prolonged therapy. A definitive cause-and-effect relationship is unclear since head trauma also was reported to cause elevated pancreatic enzymes. Intensive care practitioners should be aware of this potential reaction.

Five-year follow-up of prophylactic vena cava filters in high-risk trauma patients.

OBJECTIVE: To assess the short- and long-term outcomes of vena cava filter (VCF) placement for prophylaxis against pulmonary embolism in patients at high risk due to trauma. DESIGN AND SETTING: Case series at a level I trauma center. PATIENTS: Patients were considered for prophylactic VCF placement if they met 1 of the injury criteria--spinal cord injuries with neurologic deficit, severe fractures of the pelvis or long bone (or both), and severe head injury--and had a contraindication to anticoagulation. INTERVENTION: Vena cava filters were placed percutaneously by the interventional radiologists when the acute trauma condition was stabilized following admission. MAIN OUTCOME MEASURES: Filter tilt of 14 degrees or more, strut malposition, insertion-related deep vein thrombosis, pulmonary embolism, or inferior vena cava patency. RESULTS: There were 132 prophylactic VCFs placed. A 3.1% rate of insertion-related deep vein thrombosis occurred, all of which were asymptomatic. Filter tilt occurred in 5.5% of patients and strut malposition in 38%. Three cases of pulmonary embolism (1 fatal) occurred in a prophylactic VCF, and all patients had either filter tilt or strut malposition. The risk of pulmonary embolism developing was higher in those patients with filter tilt or strut malposition than in those who did not have these complications (6.3% vs 0%; P=.05; Fisher exact test). The 1-, 2-, and 3-year inferior vena cava patency rates (+/-SD) were 97%+/-3%. CONCLUSIONS: Prophylactic VCF can be placed safely with an acceptable rate of insertion-related deep vein thrombosis and long-term inferior vena cava patency. Patients with prophylactic VCF remain at risk for pulmonary embolism if the filter is tilted 14 degrees or more or has strut malposition. In such patients, consideration should be given to placing a second filter.

Hypertonic saline resuscitation of patients with head injury: a prospective, randomized clinical trial.

BACKGROUND: Experimental and clinical work has suggested that hypertonic saline (HTS) would be better than lactated Ringer's solution (LRS) for the resuscitation of patients with head injuries. No clinical study has examined the effect of HTS infusion on intracranial pressure (ICP) and outcome in patients with head injuries. We hypothesized that HTS infusion would result in a lower ICP and fewer medical interventions to lower ICP compared with LRS. METHODS/DESIGN: Prospective, randomized clinical trial at two teaching hospitals. RESULTS: Thirty-four patients were enrolled and were similar in age and Injury Severity Score. HTS patients had a lower admission Glasgow Coma Scale score (HTS: 4.7+/-0.7; LRS: 6.7+/-0.7; p = 0.057), a higher initial ICP (HTS: 16+/-2; LRS: 11+/-2; p = 0.06), and a higher initial mean maximum ICP (HTS: 31+/-3; LRS: 18+/-2; p < 0.01). Treatment effectively lowered ICP in both groups, and there was no significant difference between the groups in ICP at any time after entry. HTS patients required significantly more interventions (HTS: 31+/-4; LRS: 11+/-3; p < 0.01). During the study, the change in maximum ICP was positive in the LRS group but negative in the HTS group (LRS: +2+/-3; HTS: -9+/-4; p < 0.05). CONCLUSION: As a group, HTS patients had more severe head injuries. HTS and LRS used with other therapies effectively controlled the ICP. The widely held conviction that sodium administration will lead to a sustained increase in ICP is not supported by this work.

Head, face, and neck trauma from large animal injury in New Mexico.

BACKGROUND: Head, face, and neck injuries (HFNI) occur during animal-related trauma. We compared patients with HFNI and without HFNI after animal-related injuries to determine the significance of these injuries. METHODS: Retrospective review of admissions for animal injuries between January 1, 1990, and December 31, 1995, by age, gender, mechanism, animal, Glasgow Coma Scale (GCS) score, Injury Severity Score (ISS), Abbreviated Injury Severity score for head and neck (AIS Head/Neck), AIS score for face (AIS Face), intensive care unit stay, hospitalization length, morbidity, and mortality. RESULTS: There were 153 admissions: 61 HFNI and 92 no HFNI. Significant differences occurred in gender, animal, activity, GCS, and ISS. HFNI had higher AIS Head/Neck, AIS Face, and mortality. HFNI were from horses in 87% and occurred during recreation in 89%; 39% of patients with HFNI were 18 years or younger. CONCLUSION: HFNI occur in females and young people and produce lower GCS score, higher ISS, higher AIS Head/Neck, higher AIS Face, and higher mortality. Most occur during recreational horseback riding. Protective headgear should be mandated.