Resuscitative thoracotomy is a dramatic and heroic procedure used in the emergency department in an attempt to resuscitate a patient in arrest due to trauma. There are a few techniques commonly used, but due to the extreme nature of the procedure no prior randomized controlled trials (RCTs) have been done.
The modified clamshell thoracotomy (MCT) is a technique in which the standard left anterolateral thoracotomy (LAT) is extended across the sternum, but does not involve surgical opening of the right chest. The MCT allows for increased visualization of the mediastinum and thoracic cavity structures.
Sixteen Emergency trained physicians (approximately half attending and half senior residents) from a level 1 trauma center underwent didactic and skill based training on both the MCT and LAT techniques using fresh, human cadavers. Following training they were randomized based on order of intervention, performing both techniques.
Their thoracotomies were assessed by a board certified surgeon and “success” was determined based on the complete delivery of the heart and cross clamping of the descending aorta.
Primary outcome: time to successful completion of procedure
Secondary outcomes: successful delivery of the heart from the pericardial sac (as well as time to delivery), cross clamping of the aorta (and time to clamping), procedural completion and number of iatrogenic injuries.
Overall, there was no statistical difference in primary outcome or successful completion between the MCT compared to the LAT (67% vs. 40%). However, 100% of the LAT resulted in some form of iatrogenic injury (rib fractures, lacerations of the diaphragm,/esophagus/heart/lung) compared to 67% of the MCT technique. There was no associated difference in success when previous experience (attending vs. senior resident) were compared. Lastly, MCT was the favored technique of the majority of the study subjects.
The much anticipated REMAP-CAP trial was epublished ahead of print July 12th in Intensive Care Medicine. It was an RCT investigating four antiviral strategies in critically ill adults with COVID-19: lopinavir-ritonavir, hydroxychloroquine, a combination of the two, and no antiviral therapy (control group).
Despite the hype around protease inhibitors, hydroxychloroquine, and other unproven therapies in COVID (lookin at you next, Ivermectin...), all three strategies had WORSE outcomes than placebo. They all decreased organ-support-free days (all reaching statistical significance), which was the primary outcome. They also all led to longer ICU time, longer time to hospital discharge, and reduced 90 day survival. Not only does this study show no benefit, it shows fairly convincing signs of harm to these therapies.
Bottom Line: Protease inhibitors (e.g. lopinavir-ritonavir) and hydroxychloroquine are unproven therapies for critical COVID-19 infection, and are not recommended. Providers should focus on interventions with demonstrated benefit, most notably steroids and good supportive/critical care.
Hemophagocytic Lymphohistiocytosis (HLH)
Despite the knowledge that minimizing interruptions in chest compressions during CPR is key to maintaing coronary perfusion pressure and chance of ROSC,1-4 difficulties in limiting hands-off time remain.
Dewolf et al.5 recently performed a prospective observational study using body cameras to find that 33% (623/1867) of their CPR interruptions were longer than the recommended 10 seconds:
Previous studies have shown an increase in hands-off time associated with the use of cardiac POCUS during rhythm checks as well.6,7
Bottom Line:
Settings: International multicenter trials; 1:1 randomization, blinded assessment of outcomes.
Patients: adults with witnessed OHCA, regardless of initial rhythm. Patients had more than 20 minutes of CPR. Eligible patients were unconscious, not able to follow command, no verbal responses to painful stimuli.
Intervention: hypothermia to target of 33C for 28 hours, then rewarming at rate of 1/3C every hour until 37C.
Comparison: maintaining temperature at 37.5C or less. Cooling if body temperature reached 37.8C to 37.5C
Outcome: primary outcome was Any cause mortality at 6 months; secondary outcome was poor functional outcome at 6 months (modified Rankin Scale 4-6).
Study Results:
1. 930 hypothermia, mortality 465/925 (50%, RR 1.04, 95%CI 0.94-1.14); 488/881 (55%) had mRS 4-6 (RR 1.0, 95%CI 0.92-1.09).
2. 931 normothermia, mortality 446/925 (48%); 479/866 (55%) had mRS 4-6.
Discussion Points:
Conclusion:
Normothermia in coma patients after OHCA did not lead to higher morality or worse neurologic outcomes.
A recent prospective observational study examined the diagnostic usefulness of head-to-pelvis sudden death computed tomography (SDCT) in 104 patients with ROSC and unclear OHCA etiology.
Diagnostic performance:
Safety:
Bottom Line: For OHCA without clear etiology, SDCT explicitly including a thoracic CTA may have diagnostic benefit over standard care alone with the added benefit of identification of resuscitation complications.
A recent pilot study was conducted in two centers (Mayo Clinic & Cleveland Clinic Affiliate) and aimed to evaluate if the administration of oral midodrine in early septic shock could decrease the use of IV vasopressors and decrease ICU and hospital length of stay (LOS). The study was a placebo-controlled, double blinded randomized trial.
This study enrolled:
The study did not find a statistical difference between the two groups in the use of vasopressors or ICU/Hospital LOS. However, there was a trend in the midodrine group which is suggestive of decreased vasopressor use and ICU/Hospital LOS.
It is Important to note the study was not powered to determine clinical significance. Overall the trend noted in the midodrine group should encourage further studies that are clinically powered to determine if there is a statistical difference and therefore a potential benefit to early initiation of oral midodrine in septic shock.
Norepinephrine is widely considered the first-line vasopressor for patients in septic shock. Vasopressin is often added to norepinephrine in patients requiring escalating doses, but when to add vasopressin, and what exactly the benefit is (as opposed to just further titrating up the norepinephrine) remain unclear. Given the limited evidence for a patient-oriented benefit and the increasing cost of vasopressin, some centers are becoming more judicious in the use of vasopressin. A systematic review in AJEM October 2021 examined the literature on early (< 6 hours of diagnosis) addition of vasopressin to the management of septic shock patients, compared to either no vasopressin or starting it after 6 hours.
Improved with early vasopressin: Need for renal replacement therapy (RRT; secondary outcome)
No difference: mortality, ICU length of stay, hospital length of stay, new onset arrhythmias
Bottom Line: When, and if, to start vasopressin in patients requiring escalating doses of norepinephrine remains controversial. Based on the prior VASST trial, many providers will start vasopressin when norepi doses reach ~ 5-15 mcg/min (approx 0.1-0.2 mcg/kg/min), but there remains limited data to support this practice, and either starting vasopressin or continuing to titrate the norepinephrine as needed are both reasonable approaches in most patients.
Refractory Anaphylaxis
RECAP: RECOVERY trial is a large, randomized, open label, adaptive trial studying different treatments on COVID-19. Most well known is the use of dexamethasone which reduced mortality by 1/3 in COVID patients requiring mechanical ventilation and by 1/5 in those requiring oxygen, with no benefit on those patients not requiring oxygen.
They recently published results in the Lancet on the use of tocilizumab.
Population:
Inclusion:
Outcomes:
Results:
Conclusion:
Background:
Cardiac arrest from massive pulmonary embolism (PE) can be up to 90% (1). A recent systemic review evaluated the efficacy of Venoarterial-Extracorporeal Membrane Oxygenation (VA-ECMO) for PE-related cardiac arrest.
Results:
The authors screened 1115 articles and included 77 articles, including gray literature. The authors performed a quantitative analysis of a total of 301 patients.
Overall, 183/301 (61%) patients survived to hospital discharge, a significant improvement from 90%.
Patients who were cannulated during chest compression were associated with 7x higher odds of death (OR, 6.84; 95% CI, 1.53–30.58; p = 0.01), compared to those who were cannulated after ROSC. However, cannulation in the ED was not associated with improved outcomes, compared with other cannulation site.
No increased risk of death among patients who received tPA prior to VA-ECMO vs. those who did not (OR, 0.78; 95% CI, 0.39–1.54; p = 0.48).
Patients whose age > 65 years of age were associated with 3X risk of death, compared to those with age < 65 years (OR, 3.56; 95% CI, 1.29–9.87; p = 0.02).
Take-home points
Please consider “early” VA-ECMO for eligible patients who have cardiac arrest from massive PE. However, it will take great convincing to push the PERT team to cannulate for VA-ECMO while the patient is still receiving chest compression.
Background:
Cardiac arrest from massive pulmonary embolism (PE) can be up to 90% (1). A recent systemic review evaluated the efficacy of Venoarterial-Extracorporeal Membrane Oxygenation (VA-ECMO) for PE-related cardiac arrest.
Results:
The authors screened 1115 articles and included 77 articles, including gray literature. The authors performed a quantitative analysis of a total of 301 patients.
Overall, 183/301 (61%) patients survived to hospital discharge, a significant improvement from 90%.
Patients who were cannulated during chest compression were associated with 7x higher odds of death (OR, 6.84; 95% CI, 1.53–30.58; p = 0.01), compared to those who were cannulated after ROSC. However, cannulation in the ED was not associated with improved outcomes, compared with other cannulation sites.
No increased risk of death among patients who received tPA prior to VA-ECMO vs. those who did not (OR, 0.78; 95% CI, 0.39–1.54; p = 0.48).
Patients whose age > 65 years of age were associated with 3X risk of death, compared to those with age < 65 years (OR, 3.56; 95% CI, 1.29–9.87; p = 0.02).
Take-home points
Please consider “early” VA-ECMO for eligible patients who have cardiac arrest from massive PE. However, it will take great convincing to push the PERT team to cannulate for VA-ECMO while the patient is still receiving chest compression.
Supplemental oxygen therapy is frequently required for patients presenting with acute respiratory distress and COPD exacerbation. Over-oxygenation can derail compensatory physiologic responses to hypoxia,1 resulting in worsening VQ mismatch and, to a lesser degree, decreases in minute ventilation, that cause worsened respiratory failure.
The 2012 DECAF (Dyspnea, Eosinopenia, Consolidation, Acidaemia, and Atrial Fibrillation) score was found to predict risk of in-hospital mortality in patients admitted with acute COPD exacerbation.2,3 Data from the DECAF study’s derivation and external validation cohorts were examined specifically to look at outcome associated with varying levels of oxygen saturation.
Bottom Line
In patients presenting to the ED with acute COPD exacerbation requiring oxygen supplementation, a target oxygen saturation of 88-92% is associated with the lowest in-hospital mortality, and higher oxygen saturations should be avoided independent of patients' PCO2 levels.
Two items from the recent INSPIRATION trial UMEM pearl were very well pointed out by our own Dr. Michael Scott and require clarification. Thank you to all our readers for their close attention, and please know that we always appreciate you reaching out with questions/comments.
COVID-19 is generally regarded as a hypercoagulable state, and the role of pulmonary emboli and other VTE in COVID remains unclear. As a result, how to optimally provide prophylactic anticoagulation in COVID-19 patients who are not known to have VTE has been a point of debate.
The INSPIRATION trial looked at 600 patients admitted to academic ICUs in Iran, and compared what is often-referred to as "intermediate-dose" prophylaxis (in this case 1 mg/kg daily of enoxaparin) to standard dose prophylaxis (40 mg/day of enoxaparin). The study utilized a combined endpoint of venous thromboembolism, arterial thromboembolism, need for ECMO, or mortality. As a reminder, composite endpoints can skew results. However, the dose and type of anticoagulant chosen is similar to many academic centers around the world, and pharmacy guidelines often recommend providing this type of "intermediate-dose" prophylaxis in COVID-19 patients, sometimes based on clinical status, d-dimer or other coagulation-related patient-data. As with many things with COVID-19, this practice is based on limited data.
There was no significant difference between groups in the primary outcome (45.7% in intermediate ppx group vs 44.1% in standard group), and while safety outcomes were similar (major bleeding in 2.5% in the intermediate ppx group vs 1.4% in standard group), the intermediate regimen failed to demonstrate non-inferiority to the standard regimen for major bleeding.
Intermediate vs standard-dose ppx was similar in this study with a small, but statistically significant increase in major bleeding in the intermediate-dose group.
Bottom Line: Although this study had methodologic flaws and there are external validity concerns, the INSPIRATION trial supports the notion that standard dose (e.g. 40 mg/g/kg/day enoxaparin) and intermediate-dose (e.g. 1 mg/kg/day enoxaparin) VTE prophylaxis are equivalent in critically ill COVID-19 patients who do not already have a known VTE in terms of preventing negative VTE outcomes. Intermediate-dose may be associated with increased bleeding. As more critically ill patients require ED boarding, the dose of VTE prophylaxis may remain controversial, but the need to start it remains an important consideration.
Improving Compliance with Lung-Protective Ventilation
The PARAMEDIC2 trial in NEJM 2018 studied the outcomes of the use of epinephrine in outside hospital cardiac arrest (OHCA) on survival and neurological outcome.
Methods: Conducted in Britain, randomized 8007 patients to receive either epinepherine 1mg (n=4012) or placebo (n=3995) as part of standard CPR for out-of-hosptial arrest. Their primary outcome was survival at 30 days and their secondary outcomes included length of stay as well as neurological outcomes at 30 days and 3 months.
Results: The epinepherine group had improved survival to hospital admission (23% vs. 8%), at 30 days (3.2% vs. 2.4%) or at 3 months (3% vs. 2.2%). Favourable neurological outcomes, however, had no statistical difference at both hospital discharge and at 3 months.
Bottom line: Epinephrine improves ROSC, though with poor neurological outcomes.
Important facts:
Recently, a follow up of the PARAMEDIC2 trial was completed in Resuscitation.
They reported long-term survival, quality of life, functional and cognitive outcomes at 3, 6 and 12-months.
Results: At 6 months, 78 (2.0%) of the patients in the adrenaline group and 58 (1.5%) of patients in the placebo group had a favourable neurological outcome (adjusted odds ratio 1.35 [95% confidence interval: 0.93, 1.97]). 117 (2.9%) patients were alive at 6-months in the adrenaline group compared with 86 (2.2%) in the placebo group (1.43 [1.05, 1.96], reducing to 107 (2.7%) and 80 (2.0%) respectively at 12-months (1.38 [1.00, 1.92]). Measures of 3 and 6-month cognitive, functional and quality of life outcomes were reduced, but there was no strong evidence of differences between groups.
Bottom line: Epinephrine improves survival at 12 months, but poor neurological outcomes remain.
Background:
The association between time intervals of ED antibiotic administration and outcome has been controversial. While single studies showed there was increased mortality associated with delayed antibiotic administration (1-3). A meta-analysis of 13 studies and 33000 patients showed that there was no mortality difference between septic patients receiving immediate Abx (< 1 hour) vs. those receiving early abx (1-3 hours) (4).
Since delay in recognition of sepsis (defined as ED triage to Abx order) and delay in antibiotics delivery (Abx order to administration) contribute to total delay of Abx administration, a new retrospective study (3) attempted to investigate the contributions of either factor to hospital mortality.
Results:
The study used generalized linear mixed models and involved 24000 patients.
For All patients and outcome of hospital mortality:
Recognition delay (ED triage to Abx order): OR 2.7 (95% CI 1.5-4.7)*
Administration delay at 2-2.5 hours (Abx order to administration): OR 1.5 (1.1-2.0)
These results was associated with non-statistical significance in patients with septic shocks.
Conclusion:
Delayed recognition of sepsis was associated with higher hospital mortality. Longer delay of abx administration was also associated with increased risk of hospital mortality.
Clinical Question:
Methods:
Results:
Take-home points:
Background: In respiratory failure due to COPD and cardiogenic pulmonary edema, noninvasive positive pressure ventilation decreases need for intubation and improves mortality,1 while its utility in other scenarios such as ARDS and pneumonia has yet to be proven.1,2 We know that patients on NIV with delays to needed intubation have a higher mortality,1,3 but intubation and mechanical ventilation come with risks that it is preferable to avoid if possible.
So how and when can we determine that NIV is not working?
The HACOR (Heart rate, Acidosis, Consciousness, Oxygenation, Respiratory rate) score at 1 hour after NIV initiation has been demonstrated to be highly predictive of NIV failure requiring intubation.4,5
Initial development/validation: Score > 5 after 1 hour of NIV corresponds to >80% risk of NIV failure4
Earlier intubation (before 12 hours) in these patients = better survival
External validation: Score > 8 after 1 hour of NIV most predictive of eventual NIV failure 5
Average score @ 1-hour of patients with NIV success = 3.8
Score remained predictive at 6, 12, 24, 48 hours as well & mortality worsened as delay to intubation time increased
Baseline, pre-NIV score not predictive
Better predictive agreement in pneumonia and ARDS
Bottom Line:
Patients on NIV require close reassessment to prevent worsened survival due to intubation delay should invasive mechanical ventilation be indicated.
A HACOR score >8 after 1 hour of NIV should prompt intubation in most instances, with strong consideration given to a score >5.
*Note: ABGs were obtained for PaO2 assessment in the above studies -- the use of SpO2 was not evaluated -- but we are often not obtaining ABGs in our ED patients with acute respiratory failure. The following chart provides an estimated SpO2 to PaO2 conversion.
WHO 2001
Caveats:
