Ventilation In Emergency Department Research Articles

Use of non-invasive mechanical ventilation in the Emergency Department, clinical outcomes and correlates of failure

Background: Despite several studies having been carried in this organizational context, there is an absence of information about the effectiveness of non-invasive mechanical ventilation (NIV) in Emergency Departments (ED), based on a number of suitable patients with acute respiratory failure (ARF) of different aetiology. In particular, it has not yet been defined as to whether the context of the ED suits the necessary requirement of quality for the correct application of the method and if the obtained results are different from those taken in other studies in general or respiratory intensive care unit. Finally there are few data related to the predictive factors to NIV failure (endotracheal intubation, in-hospital mortality) when applied in the emergency setting. Methods: To answer these questions we have retrospectively studied a population of 210 patients (95 with COPD exsacerbation ; 92 with acute cardiogenic pulmonary oedema; 23 with severe community acquired pneumonia) treated for ARF in the “critical area” of four Italian level II Emergency Departments. For all patients demographic data; some comorbidities (diabetes, dementia, sopraventricular arrhythmias, obesity); the physiological scores (Kelly, SAPS II, Apache II); the need for pharmacological sedation; vital and blood gas parameters (evaluated at entry, after one hour of treatment and before its suspension); the ventilatory modality applied (CPAP or PSV + PEEP) and some parameters of in-hospital stay (duration of the hospitalization in the critical area, duration of ventilation, compliance to the treatment, patient's refusal to continue it, development of skin necrosis, need for endotracheal intubation, in-hospital mortality) were considered. Finally demographic, event of death with Cox regression or to the need for ETI through linear regression analysis. Results: Globally, in-hospital mortality reached 13,3%, the percentage of failure with consequent endotracheal intubation amounted to 10,4% . Considering the single aetiologic groups in the patients with COPD, exsacerbation mortality and ETI percentage were 12,6% and 13,7% respectively; in ACPO patients these data respectively amounted to 3,3% and 4,3%; while for patients with severe CAP they respectively reached 34,7% and 21,7%. The following factors were independently correlated with in-hospital mortality: SAPS II > 35, presence of dementia for COPD patients; SAPS II > 35; presence of dementia, presence of sopraventricular arrhythmias for ACPO patients; SAPS II > 35, presence of sopraventricular arrhythmias, presence of dementia for CAP patients. Considering the whole population of 210 patients, the predictive factors of in-hospital mortality were the following: SAPS II > 35; presence of dementia; presence of sopraventricular arrhythmias; maintenance of a respiratory rate above 24 bpm during tratment. The following were factors independently correlated with the need for endotracheal intubation: male gender, pH < 7,32, respiratory rate > 24 bpm, mean arterial pressure > 96 mmHg, all measured at one hour of treatment, for COPD patients; male gender sex, pH < 7,32 , respiratory rate > 24 bpm, PaCO2> 54,5 mm Hg all measured after one hour treatment for ACPO patients. Given the low number of patients, it was not possible to perform the logistic regression and to calculate the matrix of covariance of the parameter for the CAP group. Considering the whole series of patients, the factors independently correlated to ETI resulting in the following: male gender; diagnosis of COPD; pH < 7,32, respiratory rate > 24 bpm, mean arterial pressure > 96 mm Hg, PaCO2 > 54,5 mm Hg, all measured after one hour treatment. Conclusions: In conclusion, our study shows that NIV is racticable in the ED with safety and clinical results I T A L I A N J O U R N A L O F P U B L I C H E A L T H JPH - Year 6, Volume 5, Number 3, 2008 T H E M E P A P E R S 1 9 9

A Clinical Score for Predicting Successful Weaning from Noninvasive Positive Pressure Ventilation in Emergency Department; a Retrospective Cohort Study.

Noninvasive positive pressure ventilation (NIPPV) is recognized as an efficient treatment for patients with acute respiratory failure (ARF) in emergency department (ED). This study aimed to develop a scoring system for predicting successful weaning from NIPPV in patients with ARF. In this retrospective cohort study patients with ARF who received NIPPV in the ED of Ramathibodi Hospital, Thailand, between January 2020 and March 2022 were evaluated. Factors associated with weaning from NIPPV were recorded and compared between cases with and without successful weaning from NIPPV. Multivariable logistic regression analysis was used to develop a predictive model for weaning from NIPPV in ED. A total of 494 eligible patients were treated with NIPPV of whom 203(41.1%) were successfully weaned during the study period. Based on the multivariate analysis the successful NIPPV weaning (SNOW) score was designed with six factors before discontinuation: respiratory rate, heart rate ≤ 100 bpm, systolic blood pressure ≥ 100 mmHg, arterial pH≥ 7.35, arterial PaCO2, and arterial lactate. The scores were classified into three groups: low, moderate, and high. A score of >14.5 points suggested a high probability of successful weaning from NIPPV with a positive likelihood ratio of 3.58 (95%CI: 2.56-4.99; p < 0.001). The area under the receiver operating characteristic (ROC) curve of the model in predicting successful weaning was 0.79 (95% confidence interval (CI): 0.75-0.83). It seems that the SNOW score could be considered as a helpful tool for predicting successful weaning from NIPPV in ED patients with ARF. A high predictive score, particularly one that exceeds 14.5, strongly suggests a high likelihood of successful weaning from NIPPV.

Intubated Patients with Respiratory Failure under Mechanical Ventilation in Emergency Department

Background: Acute respiratory failure (ARF) is an important presentation in emergency department (ED). Intubation and mechanical ventilation (MV) are sometimes the ultimate decisions in such emergent situations. Many of these patients are unfortunately managed in an ED. This may endanger their outcome.&#x0D; This study was aimed to compare the outcome of critically ill patients with ARF under MV admitted to ED with patients admitted to ICU.&#x0D; Methods: All critically ill patients with ARF who were intubated and placed under MV were enrolled in this study. Cases were either admitted to ED or ICU. Demographic data, initial diagnosis, final diagnosis, length of hospital stay, one-month mortality rate, number of times patient was intubated and number of times patient was resuscitated were all recorded and compared between the 2 groups.&#x0D; Results: Out of all 172 patients admitted to ED and ICU, 74 (43%) were females and 98 (57%) were males. Patients had a mean±SD age of 64.2±18.1 years. ICU patients (85 patients (49.4%)) had a significantly longer hospital stay (p=0.048). ICU patients had significantly more resuscitation process (p=0.006). Mortality rate in ICU was significantly higher than ED. In the meanwhile, more patients in ED finally survived (p=0.004).&#x0D; Conclusion: In the present study, ICU patients were admitted longer to the ward than ED patients. Overall, ED mortality rate was lower than ICU. More patients finally survived in ED in comparison to ICU.

Characteristics of prolonged noninvasive ventilation in emergency departments and impact upon effectiveness. Analysis of the VNICat registry

ObjectiveTo analyze the characteristics and variables associated with prolonged noninvasive ventilation performed completely in Emergency Departments (NIV-ED) and its influence upon effectiveness. DesignA prospective, multicenter, observational multipurpose cohort study was carried out. SettingVNICAT Registry. SubjectsPatients in which NIV-ED was performed in 11 Catalan hospitals in the months of February or March 2015. InterventionNo. VariablesThe study variable was NIV-ED, which as a function of time was defined as prolonged or not prolonged. The efficacy variable was the success of the technique in terms of patient improvement. ResultsA total of 125 patients were included, with a median NIV-ED duration of 12 h, which was the cut-off point for the comparator groups. In 60 cases (48%) NIV-ED was not prolonged (<12 h), while in 65 cases (52%) ventilation was prolonged (≥12 h). Non-prolonged NIV-ED was associated to the indication of acute heart failure and prolonged ventilation to the presence of diabetes. There were no differences between non-prolonged and prolonged NIV-ED in terms of efficacy, and the success rate in terms of improvement was 68.3% and 76.9%, respectively, with an adjusted odds ratio of 1.49 (95%CI 0.61–3.60). ConclusionsProlonged NIV-ED is a frequent situation, but few variables associated to it have been studied. The presence of prolonged ventilation did not influence the success rate of NIV.

A study protocol for a multicentre, prospective, before-and-after trial evaluating the feasibility of implementing targeted SEDation after initiation of mechanical ventilation in the emergency department (The ED-SED Pilot Trial)

IntroductionSedation is a cornerstone therapy in the management of patients receiving mechanical ventilation and is highly influential on outcome. Early sedation depth appears especially influential, as early deep sedation is...

Characteristics of prolonged noninvasive ventilation in emergency departments and impact upon effectiveness. Analysis of the VNICat registry.

To analyze the characteristics and variables associated with prolonged noninvasive ventilation performed completely in Emergency Departments (NIV-ED) and its influence upon effectiveness. A prospective, multicenter, observational multipurpose cohort study was carried out. VNICat Registry. Patients in which NIV-ED was performed in 11 Catalan hospitals in the months of February or March 2015. No. The study variable was NIV-ED, which as a function of time was defined as prolonged or not prolonged. The efficacy variable was the success of the technique in terms of patient improvement. A total of 125 patients were included, with a median NIV-ED duration of 12hours, which was the cut-off point for the comparator groups. In 60 cases (48%) NIV-ED was not prolonged (<12hours), while in 65 cases (52%) ventilation was prolonged (≥12hours). Non-prolonged NIV-ED was associated to the indication of acute heart failure and prolonged ventilation to the presence of diabetes. There were no differences between non-prolonged and prolonged NIV-ED in terms of efficacy, and the success rate in terms of improvement was 68.3% and 76.9%, respectively, with an adjusted odds ratio of 1.49 (95%CI 0.61-3.60). Prolonged NIV-ED is a frequent situation, but few variables associated to it have been studied. The presence of prolonged ventilation did not influence the success rate of NIV.

Emergency nurses’ knowledge about ventilator-associated pneumonia

IntroductionGiven the increasing number of patients requiring mechanical ventilation in emergency departments in recent years, prevention of ventilator-associated pneumonia is very important. Nurses play a significant role in prevention of ventilator-associated pneumonia. This study aimed to determine the emergency nurses knowledge about prevention of ventilator-associated pneumonia. MethodsThe present descriptive study was conducted in Iran, from July to October 2018. All the nurses with at least a bachelor degree, who are working in two emergency departments of two teaching hospitals, were asked to participate in this study. The “knowledge about ventilator-associated pneumonia” questionnaire consisting of 9 items was used to assess the knowledge of nurses. The results were analyzed using SPSS-16. ResultsIn total, 53 nurses participated in this study. The mean score of correct answers of nurses to these 9 items was 4.4 ± 1.6. Nurses give the most correct answer to the item about patient's position on the bed so as to reduce the risk of pneumonia with a correct answer of 72.9%. The least correct answer was also given to the item about how humidifier was changed with a correct answer of 1.9%. None of the nurses participating in the study were able to answer all the items correctly. The mean score of knowledge of nurses who had participated in workshops about taking care of patients on mechanical ventilation was significantly higher than those who had not participated in such workshops (4.8 vs. 3.8) (p = 0.045). The mean score of knowledge in nurses who were familiar with the international guidelines for ventilator-associated pneumonia prevention was significantly higher than those who were not familiar with such guidelines (5.1 vs. 4.1) (p = 0.045). ConclusionEmergency nurses participated in this study had inadequate knowledge about the prevention of ventilator-associated pneumonia. Nurse’s knowledge affected by participation in related workshop and familiarity with ventilator-associated pneumonia guidelines. Considering the importance of this issue, it is necessary to improve the knowledge of the emergency nurses in this matter by holding training courses.

Mechanical Ventilation in the Prehospital and Emergency Department Environment.

Patients who require mechanical ventilation in the prehospital and emergency department environments experience high mortality and are at high risk of ventilator-associated ventilator-induced lung injury and ARDS. In addition, little attention has been given in the literature, trainee education, or clinical emphasis to ventilator management in these patients. ARDS and ventilator-induced lung injury are time-sensitive disease processes that develop early in mechanical ventilation and could potentially be prevented with early lung-protective ventilation. Prehospital and emergency department ventilation, in general, is characterized by potentially injurious tidal volume, high FIO2 , and low PEEP. Recent literature highlights improved subjects outcomes in the setting of early lung-protective ventilation in both subjects with and those without ARDS. This review of the literature led us to recommend that lung-protective ventilation with avoidance of hyperoxia be the default goal ventilator strategy for all patients with prehospital and emergency department mechanical ventilation. This can be achieved by delivering low tidal volumes with stepwise, concurrent titration of FIO2 and PEEP to facilitate adequate oxygenation.

Non-invasive ventilation in emergency departments in public hospitals in Catalonia. The VENUR-CAT study

ObjectivesTo know the implementation and characteristics of non-invasive ventilation (NIV) in the Emergency Departments (EDs) of public hospitals in Catalonia (Spain) and analyze possible differences based on the typology, degree of activity and the availability of an Intensive Care Unit (ICU) in the hospital. DesignA non-interventional, descriptive study was carried out, using a structured questionnaire divided into 3 sections: 1) professional experience and training; 2) devices used; and 3) clinical scenarios and the use of NIV. SettingPersons responsible for public EDs in Catalonia. ResultsFifty-two of the 54 public EDs in Catalonia responded (96.3%). Fifty-one perform NIV, which is mainly initiated by emergency care physicians (78.5%); 66.7% maintain the patient in the ED until discharge; and in 43.1% of the cases the length of stay is >24h. Of the EDs, 39.2% have their own protocol, 35.3% of which are established by consensus with other departments (more frequently in non-county hospitals [p=0.012], and centers with an ICU [p=0.014]), while 25.5% have no protocol, and 43.1% register the activity. Training represents the greatest difficulty for the implementation of NIV, but 19.6% do not provide specific training. When support is needed, the main physician of reference is the intensivist (35.3%) (more frequently in non-county hospitals [p=0.012], and centers with an ICU [p=0.002]). ConclusionsIn most EDs in Catalonia, NIV is performed by emergency care physicians. Areas needing improvement include drainage of patients once NIV has been started, the promotion of protocols, registry of activity, and training of the healthcare professionals.

Initial mechanical ventilator settings and lung protective ventilation in the ED

ObjectiveMechanical ventilation with low tidal volumes has been shown to improve outcomes for patients both with and without acute respiratory distress syndrome. This study aims to characterize mechanically ventilated patients in the emergency department (ED), describe the initial ED ventilator settings, and assess for associations between lung protective ventilation strategies in the ED and outcomes. MethodsThis was a multicenter, prospective, observational study of mechanical ventilation at 3 academic EDs. We defined lung protective ventilation as a tidal volume of less than or equal to 8 mL/kg of predicted body weight and compared outcomes for patients ventilated with lung protective vs non–lung protective ventilation, including inhospital mortality, ventilator days, intensive care unit length of stay, and hospital length of stay. ResultsData from 433 patients were analyzed. Altered mental status without respiratory pathology was the most common reason for intubation, followed by trauma and respiratory failure. Two hundred sixty-one patients (60.3%) received lung protective ventilation, but most patients were ventilated with a low positive end-expiratory pressure, high fraction of inspired oxygen strategy. Patients were ventilated in the ED for a mean of 5 hours and 7 minutes but had few ventilator adjustments. Outcomes were not significantly different between patients receiving lung protective vs non–lung protective ventilation. ConclusionsNearly 40% of ED patients were ventilated with non–lung protective ventilation as well as with low positive end-expiratory pressure and high fraction of inspired oxygen. Despite a mean ED ventilation time of more than 5 hours, few patients had adjustments made to their ventilators.

Respiratory support for children in the emergency department.

Respiratory support in paediatric emergency settings ranges from oxygen delivery with subnasal oxygen to invasive mechanical ventilation. Recent data suggest that oxygen can cause reperfusion injuries and should be delivered with caution within well-defined clinical target ranges. Most mild to moderate respiratory distress conditions with an oxygen requirement may benefit from early use of continuous positive airway pressure. High-flow nasal cannula therapy (HFNC) is an emerging alternative way to support the inspiratory effort combined with oxygen delivery and positive expiratory pressures without the need of complicated equipment or good compliance from the child. Besides a positive pressure support effect, HFNC therapy reduces the physiological dead space with improved CO2 clearance. A decrease in heart and respiratory rate within the first few hours after initiation of HFNC therapy is likely to identify responders of the treatment. The use of non-invasive ventilation such as continuous positive airway pressure or the use of bi-level positive airway pressure ventilation in emergency departments has increased, and it has been recognised that continuous positive airway pressure support for older children with asthma is particularly efficient.

Use of noninvasive positive pressure ventilation in emergency departments of public and private hospitals in Lebanon

Noninvasive positive pressure ventilation is increasingly being used in emergency departments across Europe and North America. To our knowledge, no similar data are available from other countries. The aim of this study is to describe the current use of noninvasive positive pressure ventilation in the emergency departments of Lebanese hospitals. A structured and validated questionnaire was sent to all emergency departments in Lebanon. In Lebanon, 48.4% of emergency departments use noninvasive positive pressure ventilation. It is mostly used for patients with chronic obstructive pulmonary diseases and cardiogenic pulmonary edema. Bilevel and continuous positive airway pressures are the two most widely used modalities for noninvasive positive pressure ventilation. Face mask is the most used patient interface. The use of uniform protocols and training is lacking. Noninvasive positive pressure ventilation in Lebanese emergency departments is underused, with significant potential for improvements in its current practice.

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Introduction: Compared to critically ill patients in the intensive care unit, mechanical ventilation in emergency department (ED) patients has been studied very little. There is an increased interest in acute lung injury (ALI) prevention, and defining the current practice parameters in these at-risk patients is vital before any therapeutic interventions can be investigated. The purpose of this study was to describe how mechanical ventilation is used in the ED, with respect to ventilator settings, monitored variables, and titration of settings. Hypothesis: Mechanical ventilation with high tidal volume (Vt) is common in the ED, inspiratory plateau pressure (PPLAT) is monitored infrequently, and titration of ventilation parameters is uncommon. Methods: Retrospective observational cohort study of 251 mechanically ventilated patients with severe sepsis, presenting to an urban academic ED with >95,000 annual visits (June 2005-May 2010). Descriptive statistics were used to assess ventilator settings. Lung-protective ventilation (LPV) was defined as Vt <8mL/kg ideal body weight (IBW), as this was the upper limit of Vt allowed in previous investigations of low Vt in ALI. Results: Volume-targeted ventilation (VC-AC) was used in 242 (96.4%) of patients. Median Vt was 8.8mL/kg IBW (7.8-10.0). LPV was used in 61 (24.3%) patients. PPLAT was recorded in only 76 (30.3%) patients. The 1st Vt was the highest in 236 (94%) of patients and non-LPV was used for a median of 230 (0.0-354.0) minutes. Exposure to a fraction of inspired oxygen of 1.0 occurred for a median of 251 (148-373) minutes and exposure to the same Vt for > 24 hours occurred in 60 (24.8%) patients. Conclusions: High Vt are common in intubated ED patients, as well as other potentially injurious settings, such as prolonged exposure to high levels of oxygen. PPLAT is monitored infrequently in the ED. Ventilator settings seem to be static, with relatively little titration, and this appears to extend to care beyond the ED as well. Future trials aimed at ALI prevention should consider targeting ED mechanical ventilation in patients at high risk for ALI.

Mechanical ventilation in emergency departments: Non invasive or invasive mechanical ventilation. Where is the answer?

The Emergency Department length of stay for patients requiring mechanical ventilation paper in this issue is very illustrative of many variables that still confound the way we treat patients that may not require endotracheal intubation (ETI) but may benefit from non-invasive mechanical ventilation (NIV) [1].

180 Using BOAT-S Score to Predict the Length of Hospitalization of Obese Chronic Heart Failure Patient in Emergency Department

Chronic heart failure is considered a severe cardiovascular disease seen commonly in the emergency department (ED). Emergency physicians face great challenges in the evaluation of obese chronic heart failure patients due to relatively complicated clinical entities. The aim of this study is to develop an easy and quick scoring system to help bedside evaluation of the severity and predict the length of hospitalization (length of stay) of obese chronic heart failure patients in ED. 26 different variables were analyzed as potential severity risk factors in obese chronic heart failure patients. Adjusted odds ratios were calculated using multivariate logistic regression. A point scoring system was established to predict the length of stay and validated in obese chronic heart failure patients at another facility with similar patient populations. 600 chronic heart failure patients were reviewed including 297 obese and 303 non-obese. Statistically significant difference were found between obese and non-obese chronic heart failure groups (including age 55.08±12.16 vs 58.20±12.38 p=0.001, hypoxia 20.5% vs 13.5% p=0.021, history of diabetes 62.0% vs 38.0% p<0.001, history of hypertension 90.9% vs 81.2% p=0.001, B-type natriuretic peptide level 689.94±711.53 vs 1173.92±1035.72 p<0.001, and using continuous positive airway pressure ventilation in ED 5.72% vs 0.99% p=0.001). In obese chronic heart failure patients, hypoxia (O), having atrial fibrillation with rapid ventricular response upon arrival in ED (A), taking beta blockers chronically (B), tachycardia upon arrival in ED (T), and non-smoker (-S) are considered independent risk factors to affect the length of stay in obese but not in non-obese group. BOAT-S score was developed to predict the length of stay in obese chronic heart failure patients with a sensitivity of 63.5% and a specificity of 90.3%. Additionally, BOAT-S score was validated in another group of obese chronic heart failure patients at similar ED setting with similar sensitivity (66.7%) and specificity (80.0%). Obese chronic heart failure patients are a special population that requires particular attention in terms of their severity evaluation and disposition. Using BOAT-S score may be helpful to predict the length of stay.

The Utility of Early End-Tidal Capnography in Monitoring Ventilation Status After Severe Injury

An arterial CO2 (Paco2) of 30 mm Hg to 39 mm Hg has been shown to be the ideal target range for early ventilation in trauma patients; however, this requires serial arterial blood gases. The use of end-tidal capnography (EtCO2) has been recommended as a surrogate measure of ventilation in the prehospital arena. This is based on the observation of close EtCO2 Pa(CO2) correlation in healthy patients, yet trauma patients frequently suffer from impaired pulmonary ventilation/perfusion. Thus, we hypothesize that EtCO2 will demonstrate a poor reflection of actual ventilation status after severe injury. Prospective observational study on consecutive intubated trauma patients treated in our emergency department (ED) during 9 months. Arterial blood gas values and concomitant EtCO2 levels were recorded. Regression was used to determine the strength of correlation among all trauma patients and subgroups based on injury severity (Abbreviated Injury Score and Injury Severity Score) and physiologic markers of perfusion status (lactate, shock index, and arterial base deficit). During 9 months, 180 patients were evaluated. The EtCO2 Paco2 correlation was poor at R2 = 0.277. Patients ventilated in the recommended EtCO2 (range, 35 to 40) were likely to be under ventilated (Pa(CO2) > 40 mm Hg) 80% of the time, and severely under ventilated (Pa(CO2) > 50 mm Hg) 30% of the time. Correlation was best for patients with isolated traumatic brain injury and worst for those with evidence of poor tissue perfusion. EtCO2 has low correlation with Pa(CO2), and therefore should not be used to guide ventilation in intubated trauma patients in the ED. Better strategies for guiding prehospital and ED ventilation are needed.

207: Invasive Ventilation in Australian Emergency Departments

Little published data is available on the use of invasive ventilation in emergency departments (EDs). This is an important gap in clinical knowledge, not only for patient management, but also to understand the organizational and resource implications of patients receiving invasive ventilation in EDs. The aim of this study was to characterize the current practice of invasive ventilation in Australian EDs.

Non-invasive ventilation and continuous positive pressure ventilation in emergency departments: where are we now?

A number of emergency departments have introduced non-invasive positive pressure ventilation (NIV) and continuous positive airway pressure (CPAP) for patients presenting with acute respiratory failure. It is thought that early...

Invasive ventilation in the emergency department: Part 1: What nurses need to know

Summary Mechanical ventilation is used in the resuscitation of patients with a wide range of illness and injury and in this context provides many benefits. However, when ventilation is applied inappropriately, it poses a substantial risk to patient safety. Anecdotally, within emergency departments, invasive ventilation is being employed more frequently and for prolonged periods. While the development of ventilation techniques and ventilator technology continue to expand, the majority of scientific literature on the topic focuses on its use in Intensive Care. New generation ventilators, designed for transport and short-term use are being developed that incorporate many features traditionally reserved for ventilators used in Intensive Care. Increasingly, there is a need for nurses employed within emergency departments to have a better understanding of some of the more complex ventilation techniques now available and the relative risks and benefits associated with their application. This article is the first in a two-part series which explores current modes and applications of ventilation, including developments in the current understanding of the negative effects of invasive ventilation and ways in which these may be reduced. In addition, this review will highlight gaps in the research literature regarding the application of mechanical ventilation in emergency departments.

Reliable variables in the exsanguinated patient which indicate damage control and predict outcome

Background: Exsanguination as a syndrome is ill defined. The objectives of this study were to investigate the relationship between survival and patient characteristics—vital signs, factors relating to injury and treatment; determine if threshold levels of pH, temperature, and highest estimated blood loss can predict survival; and identify predictive factors for survival and to initiate damage control. Material and methods: A retrospective 6-year study was conducted, 1993 to 1998. In all, 548 patients met one or more criteria: (1) estimated blood loss ≥2,000 mL during trauma operation; (2) required ≥1,500 mL packed red blood cells (PRBC) during resuscitation; or (3) diagnosis of exsanguination. Analysis was made in two phases: (1) death versus survival in emergency department (ED); (2) death versus survival in operating room (OR). Statistical methods were Fisher’s exact test, Student’s t test, and logistic regression. Results: For 548 patients, mean Revised Trauma Score 4.38, mean Injury Severity Score 32. Penetrating injuries 82% versus blunt injuries 18%. Vital statistics in emergency department: mean blood pressure 63 mm Hg, heart rate 78 beats per minute. Mean OR pH 7.15 and temperature 34.3°C. Mortality was 379 of 548 (69%). Predictive factors for mortality (means): pH ≤7.2, temperature <34°C, OR blood replacement >4,000 mL, total OR fluid replacement >10,000 mL, estimated blood loss >15 mL/minute ( P <0.001). Analysis 1: death versus survival in ED, logistic regression. Independent risk factors for survival: penetrating trauma, spontaneous ventilation, and no ED thoracotomy ( P <0.001; probability of survival 0.99613). Analysis 2: death versus survival in OR, logistic regression. Independent risk factors for survival: ISS ≤20, spontaneous ventilation in ED, OR PRBC replacement <4,000 mL, no ED or OR thoracotomy, absence of abdominal vascular injury ( P <0.001, max R 2 0.55, concordance 89%). Conclusions: Survival rates can be predicted in exsanguinating patients. “Damage control” should be performed using these criteria. Knowledge of these patterns can be valuable in treatment selection.