Hypovolaemic shock and pre-hospital hypertonic saline

No benefit was shown in a trial of hypertonic saline (with or without dextran) versus 0.9% saline in patients with hemorrhagic shock, in a study that was terminated early. Compare this to a similar study on head injured patients without shock by the same investigators.

OBJECTIVE: To determine whether out-of-hospital administration of hypertonic fluids would improve survival after severe injury with hemorrhagic shock.

BACKGROUND: Hypertonic fluids have potential benefit in the resuscitation of severely injured patients because of rapid restoration of tissue perfusion, with a smaller volume, and modulation of the inflammatory response, to reduce subsequent organ injury.

METHODS: Multicenter, randomized, blinded clinical trial, May 2006 to August 2008, 114 emergency medical services agencies in North America within the Resuscitation Outcomes Consortium. Inclusion criteria: injured patients, age ≥ 15 years with hypovolemic shock (systolic blood pressure ≤ 70 mm Hg or systolic blood pressure 71-90 mm Hg with heart rate ≥ 108 beats per minute). Initial resuscitation fluid, 250 mL of either 7.5% saline per 6% dextran 70 (hypertonic saline/dextran, HSD), 7.5% saline (hypertonic saline, HS), or 0.9% saline (normal saline, NS) administered by out-of-hospital providers. Primary outcome was 28-day survival. On the recommendation of the data and safety monitoring board, the study was stopped early (23% of proposed sample size) for futility and potential safety concern.

RESULTS: A total of 853 treated patients were enrolled, among whom 62% were with blunt trauma, 38% with penetrating. There was no difference in 28-day survival-HSD: 74.5% (0.1; 95% confidence interval [CI], -7.5 to 7.8); HS: 73.0% (-1.4; 95% CI, -8.7-6.0); and NS: 74.4%, P = 0.91. There was a higher mortality for the postrandomization subgroup of patients who did not receive blood transfusions in the first 24 hours, who received hypertonic fluids compared to NS [28-day mortality-HSD: 10% (5.2; 95% CI, 0.4-10.1); HS: 12.2% (7.4; 95% CI, 2.5-12.2); and NS: 4.8%, P < 0.01].

CONCLUSION: Among injured patients with hypovolemic shock, initial resuscitation fluid treatment with either HS or HSD compared with NS, did not result in superior 28-day survival. However, interpretation of these findings is limited by the early stopping of the trial.

Out-of-hospital hypertonic resuscitation after traumatic hypovolemic shock: a randomized, placebo controlled trial
Ann Surg. 2011 Mar;253(3):431-41

Neurologic complications in infective endocarditis

More than half of patients admitted to ICU with left-sided infective endocarditis developed neurologic complications

OBJECTIVE: To describe the clinical spectrum of infective endocarditis in critically ill patients and assess the impact of neurologic complications on outcomes.

DESIGN: Prospective multicenter observational study conducted from April 2007 to October 2008.

SETTING: Thirty-three intensive care units in 23 university-affiliated and 10 general French hospitals.

PATIENTS: Two hundred twenty-five patients with definite IE were studied. Factors associated with neurologic complications and predictors of 3-month mortality were identified by logistic regression analysis. Functional outcomes of patients with neurologic complications were evaluated with the modified Rankin Scale.

MEASUREMENTS AND MAIN RESULTS: Among 198 patients with definite left-sided infective endocarditis, 108 (55%) experienced at least one neurologic complication. These complications were ischemic stroke (n = 79), cerebral hemorrhage (n = 53), meningitis or meningeal reaction (n = 41), brain abscess (n = 14), and mycotic aneurysm (n = 10). Factors independently associated with neurologic complications were (subhazard ratio [95% confidence interval]): Staphylococcus aureus infective endocarditis (1.45 [1.02-2.05]), mitral valve infective endocarditis (1.54 [1.07-2.21]), and nonneurologic embolic events (1.51 [1.09-2.09]). In contrast, health care-associated infective endocarditis had a protective effect (0.46 [0.27-0.77]). Multivariate analysis identified three variables associated with 3-month mortality (odds ratio [95% confidence interval]): neurologic failure, as defined as a Glasgow Coma Scale <10 (7.41 [2.89-18.96]), S. aureus infective endocarditis (3.26 [1.53-6.94]), and severe comorbidities before admission as defined as a Charlson score >2 (3.16 [1.47-6.77]). Among the 106 patients with neurologic complications assessed at follow-up (3.9 [3-8.5] months), 31 (29%) had a modified Rankin Scale score ≤3 (ability to walk without assistance), nine (9%) a modified Rankin Scale score of 4 or 5 (severe disability), and 66 (62%) a modified Rankin Scale score of 6 (death).

CONCLUSIONS: Neurologic events are the most frequent complications in infective endocarditis patients requiring intensive care unit admission. They contribute to a severe prognosis, leaving less than one-third of patients alive with functional independence. Neurologic failure at intensive care unit admission represents a major determinant of mortality regardless of the underlying neurologic complication.

Neurologic complications and outcomes of infective endocarditis in critically ill patients: The ENDOcardite en REAnimation prospective multicenter study
Crit Care Med. 2011 Jun;39(6):1474-1481

ACEP policy on PE

The American College of Emergency Physicians has revised its 2003 clinical policy on pulmonary embolism.


 

Among the areas considered is the the role of thrombolytic medication. The policy provides the following recommendations to this question:

What are the indications for thrombolytic therapy in patients with PE?

Level B recommendations

Administer thrombolytic therapy in hemodynamically unstable patients with confirmed PE for whom the benefits of treatment outweigh the risks of life-threatening bleeding complications.*

*In centers with the capability for surgical or mechanical thrombectomy, procedural intervention may be used as an alternative therapy.

Level C recommendations

(1) Consider thrombolytic therapy in hemodynamically unstable patients with a high clinical suspicion for PE for whom the diagnosis of PE cannot be confirmed in a timely manner.

(2) At this time, there is insufficient evidence to make any recommendations regarding use of thrombolytics in any subgroup of hemodynamically stable patients. Thrombolytics have been demonstrated to result in faster improvements in right ventricular function and pulmonary perfusion, but these benefits have not translated to improvements in mortality.

The document contains a detailed appraisal of the literature to date on benefits and harms from thrombolysis. Of interest is the Pulmonary Embolism Severity Index (PESI) – a scoring system that appears to reliably predict mortality and thus has the potential to assist physicians in making risk-benefit decisions when considering administration of thrombolytics. The full text of the policy, which covers far more than just thrombolysis, can be found by following the link below.

Critical Issues in the Evaluation and Management of Adult Patients Presenting to the Emergency Department With Suspected Pulmonary Embolism
Annals of Emergency Medicine 2011 June 57(6):628-652 – Free Full Text

FAST in kids has low sensitivity

The abstract says it all – don’t use FAST to rule out significant abdominal free fluid in kids with blunt abdominal trauma. Fine as a rule-in test (for free fluid) though.

Objectives:  Focused assessment of sonography in trauma (FAST) has been shown useful to detect clinically significant hemoperitoneum in adults, but not in children. The objectives were to determine test characteristics for clinically important intraperitoneal free fluid (FF) in pediatric blunt abdominal trauma (BAT) using computed tomography (CT) or surgery as criterion reference and, second, to determine the test characteristics of FAST to detect any amount of intraperitoneal FF as detected by CT.


Methods:  This was a prospective observational study of consecutive children (0–17 years) who required trauma team activation for BAT and received either CT or laparotomy between 2004 and 2007. Experienced physicians performed and interpreted FAST. Clinically important FF was defined as moderate or greater amount of intraperitoneal FF per the radiologist CT report or surgery.


Results:  The study enrolled 431 patients, excluded 74, and analyzed data on 357. For the first objective, 23 patients had significant hemoperitoneum (22 on CT and one at surgery). Twelve of the 23 had true-positive FAST (sensitivity = 52%; 95% confidence interval [CI] = 31% to 73%). FAST was true negative in 321 of 334 (specificity = 96%; 95% CI = 93% to 98%). Twelve of 25 patients with positive FAST had significant FF on CT (positive predictive value [PPV] = 48%; 95% CI = 28% to 69%). Of 332 patients with negative FAST, 321 had no significant fluid on CT (negative predictive value [NPV] = 97%; 95% CI = 94% to 98%). Positive likelihood ratio (LR) for FF was 13.4 (95% CI = 6.9 to 26.0) while the negative LR was 0.50 (95% CI = 0.32 to 0.76). Accuracy was 93% (333 of 357, 95% CI = 90% to 96%). For the second objective, test characteristics were as follows: sensitivity = 20% (95% CI = 13% to 30%), specificity = 98% (95% CI = 95% to 99%), PPV = 76% (95% CI = 54% to 90%), NPV = 78% (95% CI = 73% to 82%), positive LR = 9.0 (95% CI = 3.7 to 21.8), negative LR = 0.81 (95% CI = 0.7 to 0.9), and accuracy = 78% (277 of 357, 95% CI = 73% to 82%).


Conclusion:  In this population of children with BAT, FAST has a low sensitivity for clinically important FF but has high specificity. A positive FAST suggests hemoperitoneum and abdominal injury, while a negative FAST aids little in decision-making

Test characteristics of focused assessment of sonography for trauma for clinically significant abdominal free fluid in pediatric blunt abdominal trauma
Acad Emerg Med. 2011 May;18(5):477-82

Steroids for trauma

A French study on adult patients intubated for multiple trauma assessed the effect of a one week course of stress-dose hydrocortisone therapy against placebo on the incidence of hospital-acquired pneumonia. Multiple trauma was defined as having 2 or more traumatic injuries and an injury severity score higher than 15. The primary outcome measure was hospital-acquired pneumonia, defined by robust criteria and requiring positive lower respiratory tract microbiology. The study was not powered to detect a difference in mortality. The authors conclude that a stress dose of hydrocortisone for 7 days is associated with a reduction in the rate of hospital-acquired pneumonia at day 28 together with a decreased requirement for mechanical ventilation and length of ICU stay in trauma patients.

An accompanying editorial, highlighting the contrast in these results with those of other steroid-studies such as the CRASH trial, which used higher doses of steroid for a shorter period, cautions:

“the overall evidence suggests that further study with a larger sample size is needed to better define the safety profile and risk of mortality in this patient population.”

Context The role of stress-dose hydrocortisone in the management of trauma patients is currently unknown.

Objective To test the efficacy of hydrocortisone therapy in trauma patients.

Design, Setting, and Patients Multicenter, randomized, double-blind, placebo-controlled HYPOLYTE (Hydrocortisone Polytraumatise) study. From November 2006 to August 2009, 150 patients with severe trauma were included in 7 intensive care units in France.

Intervention Patients were randomly assigned to a continuous intravenous infusion of either hydrocortisone (200 mg/d for 5 days, followed by 100 mg on day 6 and 50 mg on day 7) or placebo. The treatment was stopped if patients had an appropriate adrenal response.

Main Outcome Measure Hospital-acquired pneumonia within 28 days. Secondary outcomes included the duration of mechanical ventilation, hyponatremia, and death.

Results One patient withdrew consent. An intention-to-treat (ITT) analysis included the 149 patients, a modified ITT analysis included 113 patients with corticosteroid insufficiency. In the ITT analysis, 26 of 73 patients (35.6%) treated with hydrocortisone and 39 of 76 patients (51.3%) receiving placebo developed hospital-acquired pneumonia by day 28 (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.30-0.83; P = .007). In the modified ITT analysis, 20 of 56 patients (35.7%) in the hydrocortisone group and 31 of 57 patients (54.4%) in the placebo group developed hospital-acquired pneumonia by day 28 (HR, 0.47; 95% CI, 0.25-0.86; P = .01). Mechanical ventilation–free days increased with hydrocortisone by 4 days (95% CI, 2-7; P = .001) in the ITT analysis and 6 days (95% CI, 2-11; P < .001) in the modified ITT analysis. Hyponatremia was observed in 7 of 76 (9.2%) in the placebo group vs none in the hydrocortisone group (absolute difference, −9%; 95% CI, −16% to −3%; P = .01). Four of 76 patients (5.3%) in the placebo group and 6 of 73 (8.2%) in the hydrocortisone group died (absolute difference, 3%; 95% CI, −5% to 11%; P = .44).

Conclusion In intubated trauma patients, the use of an intravenous stress-dose of hydrocortisone, compared with placebo, resulted in a decreased risk of hospital-acquired pneumonia.

Hydrocortisone therapy for patients with multiple trauma: the randomized controlled HYPOLYTE study
JAMA. 2011 Mar 23;305(12):1201-9

Erythropoietin for STEMI

In STEMI patients, intravenous erythropoietin within 4 hours of PCI did not reduce infarct size and was associated with higher rates of adverse cardiovascular events

Context Acute ST-segment elevation myocardial infarction (STEMI) is a leading cause of morbidity and mortality. In experimental models of MI, erythropoietin reduces infarct size and improves left ventricular (LV) function.


Objective To evaluate the safety and efficacy of a single intravenous bolus of epoetin alfa in patients with STEMI.


Design, Setting, and Patients A prospective, randomized, double-blind, placebo-controlled trial with a dose-escalation safety phase and a single dose (60 000 U of epoetin alfa) efficacy phase; the Reduction of Infarct Expansion and Ventricular Remodeling With Erythropoietin After Large Myocardial Infarction (REVEAL) trial was conducted at 28 US sites between October 2006 and February 2010, and included 222 patients with STEMI who underwent successful percutaneous coronary intervention (PCI) as a primary or rescue reperfusion strategy.


Intervention Participants were randomly assigned to treatment with intravenous epoetin alfa or matching saline placebo administered within 4 hours of reperfusion.


Main Outcome Measure Infarct size, expressed as percentage of LV mass, assessed by cardiac magnetic resonance (CMR) imaging performed 2 to 6 days after study medication administration (first CMR) and again 12 ± 2 weeks later (second CMR).


Results In the efficacy cohort, the infarct size did not differ between groups on either the first CMR scan (n = 136; 15.8% LV mass [95% confidence interval {CI}, 13.3-18.2% LV mass] for the epoetin alfa group vs 15.0% LV mass [95% CI, 12.6-17.3% LV mass] for the placebo group; P = .67) or on the second CMR scan (n = 124; 10.6% LV mass [95% CI, 8.4-12.8% LV mass] vs 10.4% LV mass [95% CI, 8.5-12.3% LV mass], respectively; P = .89). In a prespecified analysis of patients aged 70 years or older (n = 21), the mean infarct size within the first week (first CMR) was larger in the epoetin alfa group (19.9% LV mass; 95% CI, 14.0-25.7% LV mass) than in the placebo group (11.7% LV mass; 95% CI, 7.2-16.1% LV mass) (P = .03). In the safety cohort, of the 125 patients who received epoetin alfa, the composite outcome of death, MI, stroke, or stent thrombosis occurred in 5 (4.0%; 95% CI, 1.31%-9.09%) but in none of the 97 who received placebo (P = .04).


Conclusions In patients with STEMI who had successful reperfusion with primary or rescue PCI, a single intravenous bolus of epoetin alfa within 4 hours of PCI did not reduce infarct size and was associated with higher rates of adverse cardiovascular events. Subgroup analyses raised concerns about an increase in infarct size among older patients.

Intravenous Erythropoietin in Patients With ST-Segment Elevation Myocardial Infarction
JAMA. 2011 May 11;305(18):1863-72

RSI complications increase with intubation difficulty

A substudy of a large randomised controlled trial comparing etomidate with ketamine for RSI in the pre-hospital environment, emergency department, and intensive care unit examined immediate complication rates in relation to the intubation difficulty scale score (IDS).

They used the 7-criteria IDS previously developed and evaluated. The variables included in the IDS are as follows:

  1. the number of attempts excluding the first;
  2. the number of extra operators;
  3. the number of additional techniques utilised;
  4. the Cormack grade (0–3 points, grade 1 giving no IDS points);
  5. the intensity of lifting force required (0 points if normal, 1 point if increased);
  6. the need to apply external laryngeal pressure (0 or 1 point, application of cricoid pressure (Sellick manoeuvre) does not alter the score)
  7. vocal cord position (abduction, 0 points; adduction, 1 point). Each criterion was scored and recorded by the physician who performed the procedure.

The sum gives the IDS score, and a score of 0 indicates an easy tracheal intubation at the first attempt by a single operator using a single technique, with a good view of the glottis and abducted vocal cords. Intubation was considered difficult if the score was greater than 5.

There was a positive linear relationship between IDS score and complication rate, and difficult intubation appeared to be a significant independent predictor of death.

OBJECTIVES: To evaluate the association between emergency tracheal intubation difficulty and the occurrence of immediate complications and mortality, when standardised airway management is performed by emergency physicians.


METHODS: The present study was a substudy of the KETAmine SEDation (KETASED) trial, which compared morbidity and mortality after randomisation to one of two techniques for rapid sequence intubation in an emergency setting. Intubation difficulty was measured using the intubation difficulty scale (IDS) score. Complications recognised within 5min of endotracheal intubation were recorded. We used multivariate logistic regression analysis to determine the factors associated with the occurrence of complications. Finally, a Cox proportional hazards regression model was used to examine the association of difficult intubation with survival until 28 days.


RESULTS: A total of 650 patients were included, with mean age of 55±19 years. Difficult intubation (IDS >5) was recorded in 73 (11%) patients and a total of 248 complications occurred in 192 patients (30%). Patients with at least one complication had a significantly higher median IDS score than those without any complications. The occurrence of a complication was independently associated with intubation difficulty (odds ratio 5.9; 95% confidence interval (CI) [3.5;10.1], p<0.0001) after adjustment on other significant factors. There was a positive linear relationship between IDS score and complication rate (R(2)=0.83; p<0.001). The Cox model for 28-day mortality indicated that difficult intubation (hazard ratio 1.59; 95%CI [1.04;2.42], p=0.03) was a significant independent predictor of death.


CONCLUSION: Difficult intubation, measured by the IDS score, is associated with increased morbidity and mortality in patients managed under emergent conditions.

Morbidity related to emergency endotracheal intubation—A substudy of the KETAmine SEDation trial
Resuscitation. 2011 May;82(5):517-22

Infant CPR causing rib fractures

An increase in rib fractures was observed at autopsy in infants who had undergone CPR, which is temporally related to the introduction of guidelines stressing the hand-encircling two-thumb method of CPR and compression depths of 1/3 – 1/2 the anteroposterior diameter of the chest, which has been shown in previous studies to produce higher coronary perfusion pressures and more consistently correct depth and force of compression than the “two-finger” technique.

Previous posts here have reported a CT scan-based mathematical modelling study that suggested compressing to 1/3 anteroposterior chest wall diameter should provide a superior ejection fraction to 1/4 depth and should generate less risk for over-compression than 1/2 AP compression depth, and another post described a small case series of 6 PICU patients requiring CPR for cardiac arrest due to primary cardiac disease in which blood pressure as measured by an arterial line increased when the depth of chest compression was increased from one third to one half of the chest wall diameter (using the hand-encircling method).

What should we do about this? I think the take-home message is to be mindful of the risk of rib fractures and to avoid over-compression, but to follow the guidelines. Another valuable point was made by the authors:

“Regardless of the reason for the increased incidence, the possibility of CPR-related rib fractures needs to be seriously considered in the evaluation of any infant presenting with rib fractures, when there is a history of CPR, so as not to misinterpret the finding as evidence of non-accidental/inflicted injury.”

An infant NOT requiring CPR. And a happy doctor.

OBJECTIVE: A recent increase in the number of infants presenting at autopsy with rib fractures associated with cardio-pulmonary resuscitation (CPR) precipitated a study to determine whether such a phenomenon was related to recent revision of paediatric resuscitation guidelines.


METHODS: We conducted a review of autopsy reports from 1997 to 2008 on 571 infants who had CPR performed prior to death.


RESULTS: Analysis of the study population revealed CPR-related rib fractures in 19 infants (3.3%), 14 of whom died in the 2006-2008 period. The difference in annual frequency of CPR-related fractures between the periods before and after revision of paediatric CPR guidelines was statistically highly significant.


CONCLUSIONS: The findings indicate that CPR-associated rib fractures have become more frequent in infants since changes in CPR techniques were introduced in 2005. This has important implications for both clinicians and pathologists in their assessment of rib fractures in this patient population.

Increased incidence of CPR-related rib fractures in infants-Is it related to changes in CPR technique?
Resuscitation. 2011 May;82(5):545-8

Drugs in cardiac arrest – guess what works?

Just like epinephrine (adrenaline), amiodarone does not increase survival to hospital discharge in cardiac arrest patients. I doubt his will deter the people in the resuscitation room with their stopwatches from handing me these drugs and telling me I ought to be giving them though.

Amiodarone - a load of balls

 

AIMS: In adult cardiac arrest, antiarrhythmic drugs are frequently utilized in acute management and legions of medical providers have memorized the dosage and timing of administration. However, data supporting their use is limited and is the focus of this comprehensive review.


METHODS: Databases including PubMed, Cochrane Library (including Cochrane database for systematic reviews and Cochrane Central Register of Controlled Trials), Embase, and AHA EndNote Master Library were systematically searched. Further references were gathered from cross-references from articles and reviews as well as forward search using SCOPUS and Google scholar. The inclusion criteria for this review included human studies of adult cardiac arrest and anti-arrhythmic agents, peer-review. Excluded were review articles, case series and case reports.


RESULTS: Of 185 articles found, only 25 studies met the inclusion criteria for further review. Of these, 9 were randomised controlled trials. Nearly all trials solely evaluated Ventricular Tachycardia (VT) and Ventricular Fibrillation (VF), and excluded Pulseless Electrical Activity (PEA) and asystole. In VT/VF patients, amiodarone improved survival to hospital admission, but not to hospital discharge when compared to lidocaine in two randomized controlled trials.


CONCLUSION: Amiodarone may be considered for those who have refractory VT/VF, defined as VT/VF not terminated by defibrillation, or VT/VF recurrence in out of hospital cardiac arrest or in-hospital cardiac arrest. There is inadequate evidence to support or refute the use of lidocaine and other antiarrythmic agents in the same settings.

The use of antiarrhythmic drugs for adult cardiac arrest: A systematic review
Resuscitation. 2011 Jun;82(6):665-70

Single bag for adults and kids

A nice idea – using a single adult self-inflating bag for the resuscitation of adult and paediatric patients, marked to identify compression points that deliver specific tidal volume ranges. Might be useful in situations where equipment needs to be minimised, such as military or pre-hospital settings.

AIM: To overcome limitations of inaccurate tidal volume (TV) delivery by conventional selfinflating paediatric and adult bags during paediatric and adolescent resuscitation, we designed a novel target volume marked bag (TVMB) with four compression points marked on an adult bag surface. The aim of this study was to evaluate the TVMB in delivering preset TV.


METHODS: Fifty-three subjects (28 doctors, 17 nurses, 8 paramedics) participated in this simulation trial. TVMB, paediatric bag and adult bag were connected to a gas flow analyser for measuring TV and peak inspiratory pressure (PIP). In a random cross-over setting, participants delivered 10 ventilations using the adult bag, paediatric bag or TVMB in each of four target volume ranges (100-200ml, 200-300ml, 300-400ml, 400-500ml). We compared TV and PIP for the adult bag, paediatric bag and TVMB in each subject.


RESULTS: Compared with the paediatric bag, TVMB showed higher rates of accurate TV delivery in the 200-300ml target volume range (87-90% versus 32-35%; p<0.05). Compared with the adult bag, TVMB showed higher rates of accurate TV delivery in all target volume ranges (75-90% versus 45-50%; p<0.05). The frequency of too high or low TV delivery was higher with the adult bag than TVMB (20-30% versus 0-5%; p<0.05). There was no significant difference in PIP between the paediatric bag and TVMB (within 5cm H(2)O; p<0.05).


CONCLUSIONS: TVMB could deliver accurate TV in various target volume ranges for paediatric and adolescent resuscitation.

Resuscitation. 2011 Jun;82(6):749-54