Prehospital hypotension in blunt trauma: identifying the "crump factor"

Hemodynamic Effects of Propofol for Induction of Rapid Sequence Intubation in Traumatically Injured Patients

Present guidelines for emergency intubation in traumatically injured patients recommend rapid sequence intubation (RSI) as the preferred method of airway management but specific pharmacologic agents for RSI remain controversial. To evaluate hemodynamic differences between propofol and other induction agents when used for RSI in trauma patients. Single-center, retrospective review of trauma patients intubated in the emergency department. Patients were divided in two groups based on induction agent, propofol or nonpropofol. The primary outcome was incidence of hypotension within 30 minutes of intubation. Secondary outcomes included hospital length of stay and inhospital mortality. The study protocol was approved by the Institutional Review Board. Of the 744 patients identified, 83 were analyzed, 43 in the propofol group and 40 in the nonpropofol group. Groups were similar at baseline in terms of pre-RSI hemodynamics, injury mechanism, initial Glasgow Coma Score, and Injury Severity Score. On univariate analysis, although not statistically significant, postintubation hypotension was more common in patients who received propofol compared with those who did not, 39.5 per cent versus 22.5 per cent (P = 0.9). When adjusted for age, Injury Severity Score, and pre-RSI hemodynamics, the risk of hypotension among propofol-treated patients was significantly higher (OR = 3.64; 95% Confidence interval 1.16–13.24). There were no significant differences between groups in hospital length of stay or mortality. Propofol increases the odds of postintubation hypotension in traumatically injured patients. Considerable caution should be used when contemplating the use of propofol the for induction of injured patients requiring RSI because other agents possess more favorable hemodynamic profiles.

The Evolving Science of Trauma Resuscitation

This review summarizes the evolution of trauma resuscitation from a one-size-fits-all approach to one tailored to patient physiology. The most dramatic change is in the management of actively bleeding patients, with a balanced blood product-based resuscitation approach (avoiding crystalloids) and surgery focused on hemorrhage control, not definitive care. When hemostasis has been achieved, definitive resuscitation to restore organ perfusion is initiated. This approach is associated with decreased mortality, reduced duration of stay, improved coagulation profile, and reduced crystalloid/vasopressor use. This article focuses on the tools and methods used for trauma resuscitation in the acute phase of trauma care.

A comparison of base deficit and vital signs in the early assessment of patients with penetrating trauma in a high burden setting

INTRODUCTION

An assessment of physiological status is a key step in the early assessment of trauma patients with implications for triage, investigation and management. This has traditionally been done using vital signs. Previous work from large European trauma datasets has suggested that base deficit (BD) predicts clinically important outcomes better than vital signs (VS). A BD derived classification of haemorrhagic shock appeared superior to one based on VS derived from ATLS criteria in a population of predominantly blunt trauma patients. The initial aim of this study was to see if this observation would be reproduced in penetrating trauma patients. The power of each individual variable (BD, heart rate (HR), systolic blood pressure (SBP), shock index(SI) (HR/SBP) and Glasgow Coma Score (GCS)) to predict mortality was then also compared.

METHODS

A retrospective analysis of adult trauma patients presenting to the Pietermaritzburg Metropolitan Trauma Service was performed. Patients were classified into four "shock" groups using VS or BD and the outcomes compared. Receiver Operator Characteristic (ROC) curves were then generated to compare the predictive power for mortality of each individual variable.

RESULTS

1863 patients were identified. The overall mortality rate was 2.1%. When classified by BD, HR rose and SBP fell as the "shock class" increased but not to the degree suggested by the ATLS classification. The BD classification of haemorrhagic shock appeared to predict mortality better than that based on the ATLS criteria. Mortality increased from 0.2% (Class 1) to 19.7% (Class 4) based on the 4 level BD classification. Mortality increased from 0.3% (Class 1) to 12.6% (Class 4) when classified based by VS. Area under the receiver operator characteristic (AUROC) curve analysis of the individual variables demonstrated that BD predicted mortality significantly better than HR, GCS, SBP and SI. AUROC curve (95% Confidence Interval (CI)) for BD was 0.90 (0.85-0.95) compared to HR 0.67(0.56-0.77), GCS 0.70(0.62-0.79), SBP 0.75(0.65-0.85) and SI 0.77(0.68-0.86).

CONCLUSION

BD appears superior to vital signs in the immediate physiological assessment of penetrating trauma patients. The use of BD to assess physiological status may help refine their early triage, investigation and management.

Correlation of central venous pressure with venous blood gas analysis parameters; a diagnostic study

Objective

This study was conducted to assess the correlation between central venous pressure (CVP) and venous blood gas (VBG) analysis parameters, to facilitate management of severe sepsis and septic shock in emergency department.

Material and methods

This diagnostic study was conducted from January 2014 until June 2015 in three major educational medical centers, Tehran, Iran. For patients selected with diagnosis of septic shock, peripheral blood sample was taken for testing the VBG parameters and the anion gap (AG) was calculated. All the mentioned parameters were measured again after infusion of 500 cc of normal saline 0.9% in about 1 h.

Results

Totally, 93 patients with septic shock were enrolled, 63 male and 30 female. The mean age was 72.53 ± 13.03 and the mean Shock Index (SI) before fluid therapy was 0.79 ± 0.30. AG and pH showed significant negative correlations with CVP, While HCO3 showed a significant positive correlation with CVP. These relations can be affected by the treatment modalities used in shock management such as fluid therapy, mechanical ventilation and vasopressor treatment.

Conclusion

It is likely that there is a significant statistical correlation between VBG parameters and AG with CVP, but further research is needed before implementation of the results of this study.

Isolated prehospital hypotension correlates with injury severity and outcomes in patients with trauma

Objective

Patients normotensive in the trauma bay despite documented prehospital hypotension may not be recognized as significantly injured. The purpose of this study was to determine whether isolated prehospital hypotension portends poor outcomes and correlates with injury severity.

Methods

Prospective cohort study conducted at a level 1 university trauma center. The lowest recorded prehospital systolic blood pressure (SBP) and the first recorded SBP on hospital arrival were used to divide patients into either the normotensive (NP) or hypotensive (HP) group. Patients who failed to achieve normotension on hospital arrival were excluded. Hypotension was defined as SBP≤110 mmHg.

Results

Compared to NP (n=206), HP (n=81) had lower Glasgow Coma Scores both prehospital (12.81±0.44 vs 14.38±0.13) and at hospital admission (12.78±0.47 vs 14.37±0.14). Injury Severity Score positively correlated with prehospital hypotension (HP 12.27±1.12 vs NP 9.22±0.49). Prehospital hypotension positively correlated with intensive care unit (ICU) admission (HP 56.79% vs NP 22.82%), ICU length of stay (LOS) (HP 3.23±0.71 vs NP 0.71±0.17), hospital LOS (HP 8.58±1.39 vs NP 4.86±0.33), ventilator days (HP 3.38±1.20 vs NP 0.27±0.08 days), and repeat hypotensive episodes during their hospital stay (HP 81.71% vs NP 38.16%). HP also required more packed red blood cells in the first 24 hours after admission (22% vs 6%). Significance was set at p<0.05.

Conclusions

Isolated prehospital hypotension in patients in the trauma and emergency department correlates with increased injury severity and portends worse outcomes despite a normal blood pressure reading at admission. Prehospital hypotension must be given heavy consideration in triage, as these patients may be transiently hypotensive and appear less critical than their true status.

Level of Evidence

Level II, Prognostic study.

Role of trauma team activation in poor outcomes of elderly patients

INTRODUCTION

Elderly trauma patients suffer worse outcomes than younger patients. Trauma team activation (TTA) improves outcomes in younger patients. It is unclear whether decreased TTA effectiveness or under-activation in elderly patients could contribute to their poor outcomes.

MATERIAL AND METHODS

This retrospective registry study examined all adult trauma patients admitted to a level 1 trauma center over 2 y. Analyses tested (1) whether age modifies the effect of TTA on poor outcomes, (2) whether elderly patients with severe injury were less likely to receive TTA than younger patients, and (3) which early variables were associated with poor outcomes among elderly patients who did not receive TTA.

RESULTS

The study included 10,033 patients. The adjusted relative risk from TTA for all ages was 0.48 (95% confidence interval (CI) = 0.34-0.68, P < 0.001), and there was no effect modification by age (interaction term P value, 0.171). The adjusted odds ratio for the young was 0.49 (95% CI = 0.26-0.91, P = 0.024) and for the elderly was 0.80 (95% CI = 0.53-1.20, P = 0.282). The adjusted odds ratio for lack of TTA associated with old age was 1.37 (95% CI = 1.12-1.69, P = 0.003). The strongest associations with poor outcomes were seen with low heart rate, low minimum blood pressure, high injury severity score, and high Glasgow coma score.

CONCLUSIONS

Lack of TTA could contribute to elderly patients' poor outcomes. Clinicians should not be reassured by normal heart rates and should be wary of even transiently lower blood pressures in the elderly. A large cohort study is needed to identify which additional elderly patients could benefit from TTA.

Is arterial base deficit still a useful prognostic marker in trauma? A systematic review

BACKGROUND

Arterial base deficit (BD) has been widely used in trauma patients since 1960. However, trauma management has also evolved significantly in the last 2 decades. The first objective of this study was to systematically review the literature on the relationship between arterial BD as a prognostic marker for trauma outcomes (mortality, significant injuries, and major complications) in the acute setting. The second objective was to evaluate arterial BD as a prognosis marker, specifically, in the elderly and in patients with positive blood alcohol levels.

METHODS

MEDLINE, EMBASE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews were searched from January 1, 1990, to August 6, 2015. Bibliographies of articles were also hand searched for relevant citations.

RESULTS

Thirty-four studies were included in this review. The studies consistently showed that a higher arterial BD was associated with increased mortality, significant injuries, and major complications. The threshold BD value of 6 mmol/L was also useful in discriminating for poorer outcomes. The presence of alcohol did not affect the ability of arterial BD to discriminate between major and minor injuries. Elderly patients had higher mortality in all arterial BD categories compared to the younger age group.

CONCLUSIONS

Despite the advances in trauma care in the last 2 decades, arterial BD remains a useful prognostic marker in trauma patients, even in elderly patients and in patients who had consumed alcohol. The threshold BD value of 6 mmol/L was useful to prognosticate poorer outcomes.

The use of contrast-enhanced ultrasonography for the detection of active renal hemorrhage in a dog with spontaneous kidney rupture resulting in hemoperitoneum

OBJECTIVE

To describe the use of contrast-enhanced ultrasonography (CEUS) for the detection of active renal hemorrhage in a dog with spontaneous kidney rupture resulting in hemoperitoneum.

CASE SUMMARY

A 9-month-old, sexually intact male Boxer dog presented for acute collapse, abdominal pain, and tachycardia. Physical examination findings were consistent with hypovolemia and acute abdomen. B-mode ultrasonography revealed peritoneal effusion and a right kidney mass. Subsequently, a CEUS study was performed on the right kidney, which demonstrated active hemorrhage from that kidney resulting in both hemoretroperitoneum and hemoperitoneum. At exploratory surgery, ultrasonographic findings were confirmed and a right nephrectomy was performed. Histopathology demonstrated severe parenchymal alterations along with the presence of nematode larvae. Fecal and urine testing for the presence of parasitic ova were negative. Identification of the larvae was inconclusive. At 30 days postoperatively, repeat B-mode ultrasound and clinicopathologic testing was unremarkable. The dog was alive at 1 year postsurgery with no ill effects.

NEW OR UNIQUE INFORMATION PROVIDED

To the authors' knowledge, this is the first report of CEUS for the detection of active hemorrhage from a kidney resulting in hemoretroperitoneum and hemoperitoneum in a dog. Although rare, the finding of nematode larvae within the renal parenchyma may have been the cause of kidney rupture. Importantly, surgical removal of the kidney was curative. Benign processes causing kidney rupture such as parasitic infestation should be considered in the working diagnosis as related to geographical location.

Evaluation of gasometric parameters in trauma patients during mobile prehospital care

OBJECTIVE

To evaluate gasometric differences of severe trauma patients requiring intubation in prehospital care.

METHODS

Patients requiring airway management were submitted to collection of arterial blood samples at the beginning of pre-hospital care and at arrival at the Emergency Room. We analyzed: Glasgow Coma Scale, respiratory rate, arterial pH, arterial partial pressure of CO2 (PaCO2), arterial partial pressure of O2 (PaO2), base excess (BE), hemoglobin O2 saturation (SpO2) and the relation of PaO2 and inspired O2 (PaO2/FiO2).

RESULTS

There was statistical significance of the mean differences between the data collected at the site of the accident and at the entrance of the ER as for respiratory rate (p = 0.0181), Glasgow Coma Scale (p = 0.0084), PaO2 (p <0.0001) and SpO2 (p = 0.0018).

CONCLUSION

tracheal intubation changes the parameters PaO2 and SpO2. There was no difference in metabolic parameters (pH, bicarbonate and base excess). In the analysis of blood gas parameters between survivors and non-survivors there was statistical difference between PaO2, hemoglobin oxygen saturation and base excess.

Polytrauma at the Emergency Department; can we relate arterial blood gas analysis to a shock classification?

OBJECTIVE

Shock is defined as a change of circulation which results in hypoxia at the tissue level. Lactate and base deficit (BD) are associated with a high risk of multiple organ dysfunction in trauma patients. In this study we evaluated the influence of early recognition of shock in trauma patients.

METHODS

In a retrospective study, relevant data were collected from the Radboud University Nijmegen Medical Centre (RUNMC) database between January 2009 and December 2010. Vital parameters were taken at the accident scene, and patients were divided into four shock classes. Arterial blood gas analysis was performed on arrival in the emergency department. Statistical analysis was performed with SPSS version 17.0. Statistical significance was assumed at p ≤ 0.05.

RESULTS

A total of 255 patients were included. Patients who suffered from prehospital shock, and those who were intubated prior to hospital admittance showed a bad outcome, presenting with a more severe metabolic acidosis, higher ISS and higher mortality. There was a significant difference for bicarbonate and BD between shockclass I + II and shockclass III + IV, respectively 22.7 vs. 19.7 and -3.4 vs. -6.9. Intubated patients had a decreased bicarbonate and BD compared to not intubated patients, respectively 21.81 vs. 23.24 and -5.08 vs. -2.38. Mortality and ISS were higher in patients in shock class III and IV. Significant differences in serum lactate levels were not found.

CONCLUSIONS

Prehospital shock influences patient outcome; outcome of patients is related to initial shock classification. Further validation of our shock classification, however, is necessary.

Goal-directed resuscitation in the prehospital setting: a propensity-adjusted analysis

BACKGROUND

The scope of prehospital (PH) interventions has expanded recently--not always with clear benefit. PH crystalloid resuscitation has been challenged, particularly in penetrating trauma. Optimal PH crystalloid resuscitation strategies remain unclear in blunt trauma as does the influence of PH hypotension. The objective was to characterize outcomes for PH crystalloid volume in patients with and without PH hypotension.

METHODS

Data were obtained from a multicenter prospective study of blunt injured adults transported from the scene with ISS > 15. Subjects were divided into HIGH (>500 mL) and LOW (≤500 mL) PH crystalloid groups. Propensity-adjusted regression determined the association of PH crystalloid group with mortality and acute coagulopathy (admission International Normalized Ratio, >1.5) in subjects with and without PH hypotension (systolic blood pressure [SBP], <90 mm Hg) after controlling for confounders.

RESULTS

Of 1,216 subjects, 822 (68%) received HIGH PH crystalloid and 616 (51%) had PH hypotension. Initial base deficit and ISS were similar between HIGH and LOW crystalloid groups in subjects with and without PH hypotension. In subjects without PH hypotension, HIGH crystalloid was associated with an increase in the risk of mortality (hazard ratio, 2.5; 95% confidence interval [95% CI], 1.3-4.9; p < 0.01) and acute coagulopathy (odds ratio [OR], 2.2; 95% CI, 1.01-4.9; p = 0.04) but not in subjects with PH hypotension. HIGH crystalloid was associated with correction of PH hypotension on emergency department (ED) arrival (OR, 2.02; 95% CI, 1.06-3.88; p = 0.03). The mean corrected SBP in the ED was 104 mm Hg. Each 1 mm Hg increase in ED SBP was associated with a 2% increase in survival in subjects with PH hypotension (OR, 1.02; 95% CI, 1.01-1.03; p < 0.01).

CONCLUSION

In severely injured blunt trauma patients, PH crystalloid more than 500 mL was associated with worse outcome in patients without PH hypotension but not with PH hypotension. HIGH crystalloid was associated with corrected PH hypotension. This suggests that PH resuscitation should be goal directed based on the presence or absence of PH hypotension.

Acute transfusion practice during trauma resuscitation: who, when, where and why?

BACKGROUND

Early transfusion (ET=within 24h) has been shown to be required in approximately 5% of trauma patients. Critical care transfusion guidelines control transfusion triggers by evidence based cut-offs. Empirical guidelines influence decision making for ET in trauma.

AIM

to describe the patterns, indications and timing of ET at level 1 trauma centre.

METHODS

A 12-month prospective study was performed on all trauma admissions requiring ET. Demographics, mechanism, injury severity (ISS) were collected. Timing, location, volume, the clinician initiating first unit of transfusion, reason for transfusion was recorded, with corresponding blood gas results and physiological parameters. Mortality, ICU admission, length of stay, need for emergent surgery were outcomes.

RESULTS

From 965 trauma admissions 91 (9%) required ET (76% male, median age: 38 (10-88, IQR: 22-59), blunt mechanism: 87%, ISS: 25 (4-66, IQR: 16-34). 43% (39/91) had massive transfusion protocol (MTP) activation. ET was initiated in ED (52%), OR (38%) or ICU (10%). MTP transfusions were started at a median of 0.5h (0.5-4, IQR: 0.5-1.5), whilst non-MTP transfusions were initiated at a median 3h (0.5-23, IQR: 2-9). The first unit of ET was initiated by trauma surgeon (35%), anaesthetist (30%), ED (19%), ICU (13%) and general surgeon (3%). Transfusions triggers at the first unit of transfusion were 'expected or ongoing bleeding' 29%, dropping haemoglobin 26%, haemorrhagic shock 24%, hypotension 10%, tachycardia 8%. Median systolic blood pressure was 90 (45-125, IQR: 80-100), heart rate was 100 (53-163, IQR: 80-120), haemoglobin was 96 (50-166, IQR: 85-114)g/l and base excess was -4.2(-22.1 to 2.7, IQR: -7.2 to 2.4)mmol/l at the time of transfusion. Emergency surgery was required in 86% (78/91). ICU admission rate was 69% (63/91). Mortality was 14%. Low volume transfusion (1-2 units) was more likely to lead to overtransfusion (Hb>110 g/l).

CONCLUSION

The prospective evaluation of acutely transfused trauma patients showed a distinct pattern of transfusion triggers as the patient passes from ED to the OT and arrives to the ICU. The conventional transfusion trigger (haemoglobin level) is not appropriate in ET as early transfusion triggers are based on vital signs, blood gas results, injury patterns and anticipated major bleeding.

A normal platelet count may not be enough: the impact of admission platelet count on mortality and transfusion in severely injured trauma patients

BACKGROUND

Platelets play a central role in hemostasis after trauma. However, the platelet count of most trauma patients does not fall below the normal range (100-450 × 10(9)/L), and as a result, admission platelet count has not been adequately investigated as a predictor of outcome. The purpose of this study was to examine the relationship between admission platelet count and outcomes after trauma.

METHODS

A retrospective cohort study of 389 massively transfused trauma patients. Regression methods and the Kruskal-Wallis test were used to test the association between admission platelet count and 24-hour mortality and units of packed red blood cells (PRBCs) transfused.

RESULTS

For every 50 × 10(9)/L increase in admission platelet count, the odds of death decreased 17% at 6 hours (p = 0.03; 95% confidence interval [CI], 0.70-0.99) and 14% at 24 hours (p = 0.02; 95% CI, 0.75-0.98). The probability of death at 24 hours decreased with increasing platelet count. For every 50 × 10(9)/L increase in platelet count, patients received 0.7 fewer units of blood within the first 6 hours (p = 0.01; 95% CI, -1.3 to -0.14) and one less unit of blood within the first 24 hours (p = 0.002; 95% CI, -1.6 to -0.36). The mean number of units of PRBCs transfused within the first 6 hours and 24 hours decreased with increasing platelet count.

CONCLUSIONS

Admission platelet count was inversely correlated with 24-hour mortality and transfusion of PRBCs. A normal platelet count may be insufficient after severe trauma, and as a result, these patients may benefit from a lower platelet transfusion threshold. Future studies of platelet number and function after injury are needed.

Initial systolic blood pressure and ongoing internal bleeding following torso trauma

Objective:

Recent studies have suggested that an initial systolic blood pressure (SBP) in the range of 90–110 mmHg in a trauma patient may be indicative of hypoperfusion and is associated with poor patient outcome. However, the use of initial SBP as a surrogate for predicting internal bleeding is yet to be validated. The purpose of this study was to assess the presenting SBPs in patients with torso trauma and evidence of ongoing internal hemorrhage.

Setting and Design:

This was a retrospective chart review conducted at the Level II Trauma Center.

Patients and Methods:

Adult patients who sustained trauma and underwent chest and/or abdominal computed tomography (CT) scans and angiography were included in the study. Demographic and clinical information was extracted from patients who had CT scan and angiography. Extravasation of contrast material on CT scan and angiography was considered positive for ongoing internal bleeding.

Results:

From January 2002 through July 2007, a total of 113 consecutive patients were included in this study. Forty-seven patients had evidence of ongoing internal bleeding (41.6%; 95% confidence interval: 32.4%, 51.2%). When comparing patients with and without ongoing bleeding, these two groups were similar in their gender, race, pulse, injury severity score and shock index. However, bleeding patients were typically older [mean (standard deviation): 44.5 (20.5) vs 37.3 (19.1) years; P = 0.051], had a lower initial SBP [116.2 (36.0) vs 130.0 (30.4) mmHg; P = 0.006] and had a higher Glasgow coma scale (GCS) [13.1 (4.0) vs 12.1 (4.4); P = 0.09]. From a multivariate logistic regression analysis, older age (P = 0.046) and lower SBP (P = 0.01) were significantly associated with bleeding, when controlled for gender, race and GCS. Among the 47 patients with ongoing bleeding, only seven patients (15%) had a SBP lower than 90 mmHg and 25 patients (53%) had a SBP higher than or equal to 120 mmHg. The spleen was the most frequently injured organ identified with active bleeding.

Conclusions:

Initial SBP cannot predict the ongoing internal bleeding.