Yearly Archives: 2012

All Updates, ICU, Kids, Resus

ECMO for paediatric cardiac arrest

Leave a comment

The Taiwanese are at it again with their extracorporeal life support. This time, they report their outcomes in children who received ECMO for in-hospital cardiac arrest. Interestingly, the patients with pure cardiac causes of cardiac arrest had a survival rate similar to patients with non-cardiac causes.


PURPOSE: The study aims to describe 11 years of experience with extracorporeal cardiopulmonary resuscitation (ECPR) for in-hospital paediatric cardiac arrest in a university affiliated tertiary care hospital.

METHODS: Paediatric patients who received extracorporeal membrane oxygenation (ECMO) during active extracorporeal cardiopulmonary resuscitation (ECPR) at our centre from 1999 to 2009 were included in this retrospective study. The results from three different cohorts (1999-2001, 2002-2005 and 2006-2009) were compared. Survival rates and neurological outcomes were analysed. Favourable neurological outcome was defined as paediatric cerebral performance categories (PCPC) 1, 2 and 3.

RESULTS: We identified 54 ECPR events. The survival rate to hospital discharge was 46% (25/54), and 21 (84%) of the survivors had favourable neurological outcomes. The duration of CPR was 39±17 min in the survivors and 52±45 min in the non-survivors (p=NS). The patients with pure cardiac causes of cardiac arrest had a survival rate similar to patients with non-cardiac causes (47% (18/38) vs. 44% (7/16), p=NS). The non-survivors had higher serum lactate levels prior to ECPR (13.4±6.4 vs. 8.8±5.1 mmol/L, p<0.01) and more renal failure after ECPR (66% (19/29) vs. 20% (5/25), p<0.01). The patients resuscitated between 2006 and 2009 had shorter durations of CPR (34±13 vs. 78±76 min, p=0.032) and higher rates of survival (55% (16/29) vs. 0% (0/8), p=0.017) than those resuscitated between 1999 and 2002.

CONCLUSIONS: In our single-centre experience with ECPR for paediatric in-hospital cardiac arrest, the duration of CPR has become shorter and outcomes have improved in recent years. Higher pre-ECPR lactate levels and the presence of post-ECPR renal failure were associated with increased mortality. The presence of non-cardiac causes of cardiac arrest did not preclude successful ECPR outcomes. The duration of CPR was not significantly associated with poor outcomes in this study.

Eleven years of experience with extracorporeal cardiopulmonary resuscitation for paediatric patients with in-hospital cardiac arrest
Resuscitation. 2012 Jun;83(6):710-4

Acute Med, All Updates, ICU, Resus

Surgical treatment for acute massive pulmonary embolism

Leave a comment

A recent paper reminds us that surgery is an option in the management of massive pulmonary embolism(1), to be considered in the patient for whom thrombolysis has failed or is contraindicated. Good outcomes were produced when surgery was performed in a centre capable of cardiopulmonary bypass (6% 30-day postoperative mortality), but is surgery an option when these facilities are unavailable?

The “venous inflow occlusion” technique involves clamping the venae cavae prior to removing clot directly from the pulmonary artery and its branches after median sternotomy, and can be performed in any hospital with surgical facilities. Under normothermic conditions, speed is of the essence once cardiac arrest occurs, since the irreversible anoxic cerebral injury will occur after just a few minutes.
Clarke and Abrams wrote in the Lancet in 1972(2):

Our use of venous inflow-occlusion has given results which compare well with those obtained with extracorporeal circulation. 50% of our patients survived. All patients who had emboli removed without an episode of ventricular asystole survived surgery. Late deaths in 3 patients were from causes unrelated to pulmonary embolism, and from a further massive pulmonary embolus a week later. The technique has been applied with equal success in a major hospital fully equipped for cardiac surgery and in hospitals where resident and nursing staff had no experience of either thoracic or cardiac surgery. The simplicity and speed of the method has enabled the obstructed right ventricle to be relieved within thirty minutes of the onset of symptoms. The interval between induction of anaesthesia and the skin incision should be kept as short as possible, and drugs to maintain the blood pressure should be given. The period between skin incision and the restoration of the circulation has, with practice, been reduced to ten minutes.

But this clearly still requires surgical expertise and facilities. Emergency physicians can open the chest to deal with penetrating trauma. Could an ED thoracotomy facilitate clot removal from the pulmonary artery?

In 1969, a lady in her 50s arrested on the ward after an operation to remove a mass via a left lateral thoractomy. Pulmonary embolism was suspected and her thoracotomy wound was re-opened and the pulmonary artery incised, resulting in the removal of large amounts of clot. Return of spontaneous circulation resulted after a brief period of internal cardiac massage. Her case was written up decades later, in 1998(3):

The patient recovered rapidly and left the hospital on the 21st day without signs of cerebral damage. This patient is now 86 years old, mentally normal, living alone, and doing her own housekeeping. She remembers the hospital stay and the past years as worth living

Some patients may be considered too high risk for surgery and in some centres Extracorporeal Membrane Oxygenation (ECMO) is an option. It has been used both as life support pending surgery(4), or as an alternative to surgery to allow heparinisation to be used(5,6).

In summary, some patients with massive pulmonary embolism may benefit from surgery (contraindication to ‘lysis or failed ‘lysis). Getting them to surgery alive, or operating on them during cardiac arrest, is a challenge. Ideally they would undergo embolectomy under cardopulmonary bypass in the operating room, or could be placed on ECMO in the ED prior to going to the OR. If they present to a centre without these facilities, then the venous inflow occlusion technique could be used in the OR without bypass. Just rarely a patient may present in extremis with PE to an ED without these options. If that patient has major contraindications to thrombolysis, would an ED thoracotomy be something you would entertain?

I have done several thoracotomies for penetrating trauma but never for PE. I do not pretend to know how, and cannot find a case report of ED thoracotomy for pulmonary embolism in the literature. I’m therefore NOT recommending it. However, I would love to know people’s views on its feasibility. A possible approach could be summarised as:

Massive pulmonary embolism fascinates me, because it’s seen in the ‘talk and die’ patient. It is a single, treatable pathology that if diagnosed and treated appropriately truly makes the difference between life and death. When medicine presents us with an opportunity ‘on a plate’ like that to save a life, we need to be prepared. I have had great saves with this diagnosis and sadly have seen disastrous failures to act. When the time comes, we need to ask: ‘have we explored all options?’.

1. Surgical treatment of acute pulmonary embolism–a 12-year retrospective analysis.
Scand Cardiovasc J. 2012 Jun;46(3):172-6. Epub 2012 Mar 27.

OBJECTIVES: Surgical embolectomy for acute pulmonary embolism (PE) is considered to be a high risk procedure and therefore a last treatment option. We wanted to evaluate the procedures role in modern treatment of acute PE.
DESIGN: All data on patients treated with surgical embolectomy for acute PE were retrieved from our clinical database. The mortality was extracted from the Danish mortality register.
RESULTS: From October 1998 to July 2010, 33 patients underwent surgical embolectomy. All procedures were done through a median sternotomy and extracorporeal circulation. Twenty-six patients were diagnosed with a high risk PE and 7 with an intermediate risk PE and intracardial pathology. Six patients had been insufficiently treated with thrombolysis. Thirteen patients had contraindication for thrombolysis. Six patients were brought to the operating theatre in cardiogenic shock, 8 needed ventilator support, and 1 was in cardiac arrest. The postoperative 30-day mortality was 6% and during the 12-year follow-up the cumulative survival was 80% with 4 late deaths.
CONCLUSION: Surgical pulmonary embolectomy can be performed with low mortality although the treated patients belong to the most compromised part of the PE population. The results support surgical embolectomy as a vital part of the treatment algorithm for acute PE.

2. Pulmonary embolectomy with venous inflow-occlusion.
The Lancet 1972;1(7754):767–769

Massive pulmonary emboli have been removed surgically from 26 patients. The technique of normothermic circulatory arrest by venous inflow-occlusion was used in 25 patients. 13 patients survived. There were 10 operative deaths and 3 hospital deaths. Diagnosis was based upon clinical findings supplemented by electrocardiography and a plain radiograph of the chest. Surgery was offered to patients having a pulmonary embolus sufficiently massive to produce sustained hypotension. All patients whose hearts stopped beating before the embolectomy died. 6 successful operations were performed in hospitals without facilities for cardiac surgery. The method is recommended for its simplicity.

3. Left Anterior Thoracotomy for Pulmonary Embolectomy With 29-Year Follow-up
The Annals of Thoracic Surgery 1998, 66(4):1420-1421

Pulmonary embolectomy is usually performed in cardiopulmonary bypass. In acute situations too much time can be lost in setting up and connecting the pump oxygenator; this delay can cause cerebral damage in a patient with circulatory arrest. In such a situation left anterior thoracotomy can provide an ideal approach. An emergency thoracotomy can be performed in a few seconds. The lung automatically retracts. The phrenic nerve, pulmonary artery, and pericardium are clearly seen, and they outline the area for embolectomy. A case in which such an approach was successfully used is described.

4.ECMO treatment saved life of a young woman with acute pulmonary embolism
Lakartidningen 2004, 101(44):3420-3421

A 42-year old obese female using contraceptive medication was admitted to the emergency room because of sudden onset of dyspnoea and hypoxia. Computed tomography showed massive pulmonary emboli. Despite initial treatment with thrombolysis her condition deteriorated further and she was referred for acute surgery to our clinic. Before putting the patient to sleep extracorporeal circulation was instituted with access from the groin. After anaesthesia a median sternotomy was performed. With the heart beating, the main pulmonary artery was incised and a 9 cm long thrombus was removed. Immediate weaning from the heart-lung machine was not possible, mainly because of bleeding to the airways. The right atrium and the aorta was therefore cannulated and an extracorporeal circulation membrane oxygenator (ECMO) was used for three days. The patient required several re-entries for bleeding and a tracheotomy during the postoperative course. She was fully recovered three months after the operation.

5. Extracorporeal membrane oxygenator for pulmonary embolism.
The Annals of Thoracic Surgery 1997, 64(3):883-884 Free full text

6. Peripheral Extracorporeal Membrane Oxygenation: Comprehensive Therapy for High-Risk Massive Pulmonary Embolism
Ann Thorac Surg 2012;94:104–8

Background: Although commonly reserved as a last line of defense, experienced centers have reported excellent results with pulmonary embolectomy for massive and submassive pulmonary embolism (PE). We present a contemporary surgical series for PE that demonstrates the utility of peripheral extracorporeal membrane oxygenation (pECMO) for high-risk surgical candidates.
Methods: Between June 2005 and April 2011, 29 patients were treated for massive or submassive pulmonary embolism, with surgical embolectomy performed in 26. Four high-risk patients were placed on pECMO, established by percutaneously cannulating the right atrium through a femoral vein and perfusing by a Dacron graft anastomosed to the axillary artery. A small, extracorporeal, rotary assist device was used, interposing a compact oxygenator in the circuit, and maintaining anticoagulation with heparin.
Results: Extracorporeal membrane oxygenation was weaned in 3 of 4 patients after 5.3 days (5, 5, and 6), with normalization of right ventricular dysfunction and pulmonary artery pressure (44.0 ± 2.0 to 24.5 ± 5.5 mm Hg) by ECHO. Follow-up computed tomographies showed several peripheral, nearly resorbed emboli in 1 case and complete resolution in 2 others. The fourth patient, not improving after 10 days, underwent surgery where an embolic liposarcoma was extracted. For all 29 cases, hospital and 30-day mortality was 0% and all patients were discharged, with average postoperative length of stay of 15 days for embolectomy and 17 days for pECMO.
Conclusions: Heparin therapy with pECMO support is a rapid, effective option for patients who might benefit from pulmonary embolectomy but are at high risk for surgery.

All Updates, PHARM, Resus, Trauma

What is 'hypotension' in penetrating trauma?

Leave a comment

I previously noted an article demonstrating that a ‘lowish’ – as opposed to a low – systolic blood pressure is a reason to be vigilant in blunt trauma patients, as a significant increase in mortality has been demonstrated with a systolic blood pressure (SBP) < 110 mmHg.
The same researchers have found similar results in patients with penetrating trauma.
Compared with the reference group with SBP 110-129mmHg, mortality was doubled at SBP 90-109mmHg, was four-fold higher at 70-89mmHg and 10-fold higher at <70mmHg. SBP values ≥150mmHg were associated with decreased mortality.
Systolic blood pressure below 110 mmHg is associated with increased mortality in penetrating major trauma patients: Multicentre cohort study
Resuscitation. 2012 Apr;83(4):476-81
[EXPAND Click for abstract]


INTRODUCTION: Non-invasive systolic blood pressure (SBP) measurement is a commonly used triaging tool for trauma patients. A SBP of <90mmHg has represented the threshold for hypotension for many years, but recent studies have suggested redefining hypotension at lower levels. We therefore examined the association between SBP and mortality in penetrating trauma patients.

METHODS: We conducted a prospective cohort study in adult (≥16 years) penetrating trauma patients. Patients were admitted to hospitals belonging to the Trauma Audit and Research Network (TARN) between 2000 and 2009. The main outcome measure was the association between SBP and mortality at 30 days. Multivariate logistic regression models adjusted for the influence of age, gender, Injury Severity Score (ISS) and Glasgow Coma Score (GCS) on mortality were used. RESULTS: 3444 patients with a median age of 30 years (IQR 22.5-41.4), SBP of 126mmHg (IQR 107-142), ISS of 9 (IQR 9-14) and GCS of 15 (IQR 15-15), were analysed. Multivariable logistic regression analysis adjusted for age, gender, severity of injury and level of consciousness showed a cut-off for SBP at <110mmHg, after which increased mortality was observed. Compared with the reference group with SBP 110-129mmHg, mortality was doubled at SBP 90-109mmHg, was four-fold higher at 70-89mmHg and 10-fold higher at <70mmHg. SBP values ≥150mmHg were associated with decreased mortality.

CONCLUSION: We recommend that penetrating trauma patients with a SBP<110mmHg are triaged to resuscitation areas within dedicated, appropriately specialised, high-level care trauma centres.

[/EXPAND]

Acute Med, All Updates, Resus

Facilitated pericardial drainage

Leave a comment

Drs Wyatt and Haugh describe a modified resuscitative thoracotomy technique which provided surgically facilitated pericardial drainage. A patient with a ruptured pseudoaneurysm of the right ventricular outflow tract presented in shock and arrested in the ED. She had had a prior history of idiopathic ventricular tachycardia and had undergone cardiac ablation of the posteroseptal wall of the right ventricular outflow tract. Sonographically identified tamponade was treated with pericardiocentesis which failed due to clotted blood, so a left lateral thoracotomy was performed by the emergency physician. Rather than fully expose the heart for repair in the ED, they elected to just make a 2cm incision in the pericardium which allowed drainage of blood and restoration of circulation. This was combined with blood product transfusion to buy time for the arrival of a cardiothoracic surgeon and transfer to the operating room.
Useful learning points from this paper are:

  • Ablation procedures are becoming more common
  • Serious complications such as atrioesophageal fistula, pseudoaneurysm, pericardial effusion, and cardiac tamponade occur approximately 3% of the time
  • When tamponade is suspected or confirmed ask patient about recent cardiac procedures such as catheterisations, surgery, and ablation procedures
  • Radiofrequency ablation procedures are often performed on the right side of the heart in areas that may be relatively inaccessible from a left-sided lateral thoracotomy approach.

Modified Emergency Department Thoracotomy for Postablation Cardiac Tamponade
Ann Emerg Med. 2012 Apr;59(4):265-7
[EXPAND Click for abstract]


Cardiac dysrhythmias are a common problem in the United States. Radiofrequency ablation is being used more frequently as a treatment for these diagnoses. Although rare, serious complications such as cardiac tamponade have been reported as a result of ablation procedures. Traditionally, emergency department (ED) thoracotomy has been reserved for cases of traumatic arrest only. We report a case of a successful modified ED thoracotomy in a patient with postablation cardiac tamponade and subsequent obstructive shock who failed intravenous fluid resuscitation, pressor administration, and multiple attempts at pericardiocentesis. In this case, a modified approach was used to incise the pericardium. Although this was associated with large blood loss, we believed that using the traditional method of completely removing the pericardium would have resulted in uncontrolled hemorrhage. Instead, our method led to successful resuscitation of the patient until definitive care was available. A smaller pericardial incision than is traditionally used during ED thoracotomy deserves further consideration and research to determine whether and when it may be most useful as a temporizing treatment of cardiac tamponade when other methods have failed.

[/EXPAND]

Acute Med, All Updates, ICU, Resus

Magnesium doesn't improve SAH outcome

Leave a comment

A multicentre RCT showed intravenous magnesium sulphate does not improve clinical outcome after aneurysmal subarachnoid haemorrhage, therefore routine administration of magnesium cannot be recommended.
Magnesium for aneurysmal subarachnoid haemorrhage (MASH-2): a randomised placebo-controlled trial
Lancet 2012 July 7; 380(9836): 44–49 Free full text
[EXPAND Click to read abstract]


Background Magnesium sulphate is a neuroprotective agent that might improve outcome after aneurysmal subarachnoid haemorrhage by reducing the occurrence or improving the outcome of delayed cerebral ischaemia. We did a trial to test whether magnesium therapy improves outcome after aneurysmal subarachnoid haemorrhage.

Methods We did this phase 3 randomised, placebo-controlled trial in eight centres in Europe and South America. We randomly assigned (with computer-generated random numbers, with permuted blocks of four, stratified by centre) patients aged 18 years or older with an aneurysmal pattern of subarachnoid haemorrhage on brain imaging who were admitted to hospital within 4 days of haemorrhage, to receive intravenous magnesium sulphate, 64 mmol/day, or placebo. We excluded patients with renal failure or bodyweight lower than 50 kg. Patients, treating physicians, and investigators assessing outcomes and analysing data were masked to the allocation. The primary outcome was poor outcome—defined as a score of 4–5 on the modified Rankin Scale—3 months after subarachnoid haemorrhage, or death. We analysed results by intention to treat. We also updated a previous meta-analysis of trials of magnesium treatment for aneurysmal subarachnoid haemorrhage. This study is registered with controlled-trials.com (ISRCTN 68742385) and the EU Clinical Trials Register (EudraCT 2006-003523-36).

Findings 1204 patients were enrolled, one of whom had his treatment allocation lost. 606 patients were assigned to the magnesium group (two lost to follow-up), 597 to the placebo (one lost to follow-up). 158 patients (26·2%) had poor outcome in the magnesium group compared with 151 (25·3%) in the placebo group (risk ratio [RR] 1·03, 95% CI 0·85–1·25). Our updated meta-analysis of seven randomised trials involving 2047 patients shows that magnesium is not superior to placebo for reduction of poor outcome after aneurysmal subarachnoid haemorrhage (RR 0·96, 95% CI 0·86–1·08).

Interpretation Intravenous magnesium sulphate does not improve clinical outcome after aneurysmal subarachnoid haemorrhage, therefore routine administration of magnesium cannot be recommended.

[/EXPAND]

Acute Med, All Updates, ICU, Resus

More on the meaning of lactate values

Leave a comment

A newly published study(1) reminds us that we need to do better than just identify a raised lactate in patients with sepsis; we need to make sure it’s not increasing when they leave the ED (if we can). An incremental rise is associated with mortality.

The authors comment:


We found that the prognostic value of lactate continues to rise across a wide range of values, from 0 to 20 mmol/L…. These data suggest that grouping patients into less granular and larger groups, such as low, intermediate, and high, potentially underutilizes the prognostic value of the test. Furthermore, we did not find any value of lactate, up to a maximum value of 20 mmol/L, where mortality failed to increase with an increase in lactate concentration.

The paper does not state whether the lactate was arterial or venous, although either can be used. The Surviving Sepsis Campaign provides this comment:


In the course of the Campaign the question has been raised many times as to whether an arterial or venous lactate sample is appropriate. While there is no consensus of settled literature on this question, an elevated lactate of any variety is typically abnormal, although this may be influenced by other conditions..

This relationship between lactate trend and mortality has also been demonstrated in a study of all patients admitted to hospital (with or without sepsis), which also showed good correlation between arterial and venous lactate(2).

Lactate clearance has been shown to be an acceptable alternative to central venous oxygen saturation as a goal for therapy in ED severe sepsis patients(3), which is good because it provides one less reason for a central line.

Always remember the good emergency physician / critical care practitioner will consider other causes of a raised lactate, particularly when things don’t add up. I invented the ‘LACTATES’ acronym to help me remember them(4), and it’s come in handy several times.

Craving more info on lactate? Check out the EMCrit site with its great lactate reference sheet.

1. Prognostic Value of Incremental Lactate Elevations in Emergency Department Patients With Suspected Infection
Acad Emerg Med. 2012 Aug;19(8):983-5
[EXPAND Click for abstract]


Objectives:  Previous studies have confirmed the prognostic significance of lactate concentrations categorized into groups (low, intermediate, high) among emergency department (ED) patients with suspected infection. Although the relationship between lactate concentrations categorized into groups and mortality appears to be linear, the relationship between lactate as a continuous measurement and mortality is uncertain. This study sought to evaluate the association between blood lactate concentrations along an incremental continuum up to a maximum value of 20 mmol/L and mortality.

Methods:  This was a retrospective cohort analysis of adult ED patients with suspected infection from a large urban ED during 2007–2010. Inclusion criteria were suspected infection evidenced by administration of antibiotics in the ED and measurement of whole blood lactate in the ED. The primary outcome was in-hospital mortality. Logistic and polynomial regression were used to model the relationship between lactate concentration and mortality.

Results:  A total of 2,596 patients met inclusion criteria and were analyzed. The initial median lactate concentration was 2.1 mmol/L (interquartile range [IQR] = 1.3 to 3.3 mmol/L) and the overall mortality rate was 14.4%. In the cohort, 459 patients (17.6%) had initial lactate levels >4 mmol/L. Mortality continued to rise across the continuum of incremental elevations, from 6% for lactate <1.0 mmol/L up to 39% for lactate 19–20 mmol/L. Polynomial regression analysis showed a strong curvilinear correlation between lactate and mortality (R = 0.72, p < 0.0001).
Conclusions:  In ED patients with suspected infection, we found a curvilinear relationship between incremental elevations in lactate concentration and mortality. These data support the use of lactate as a continuous variable rather than a categorical variable for prognostic purposes.

[/EXPAND]
2. Blood lactate as a predictor for in-hospital mortality in patients admitted acutely to hospital: a systematic review
Scand J Trauma Resusc Emerg Med. 2011 Dec 28;19:74 Free Full Text
[EXPAND Click for abstract]


BACKGROUND: Using blood lactate monitoring for risk assessment in the critically ill patient remains controversial. Some of the discrepancy is due to uncertainty regarding the appropriate reference interval, and whether to perform a single lactate measurement as a screening method at admission to the hospital, or serial lactate measurements. Furthermore there is no consensus whether the sample should be drawn from arterial, peripheral venous, or capillary blood. The aim of this review was: 1) To examine whether blood lactate levels are predictive for in-hospital mortality in patients in the acute setting, i.e. patients assessed pre-hospitally, in the trauma centre, emergency department, or intensive care unit. 2) To examine the agreement between arterial, peripheral venous, and capillary blood lactate levels in patients in the acute setting.

METHODS: We performed a systematic search using PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL up to April 2011. 66 articles were considered potentially relevant and evaluated in full text, of these ultimately 33 articles were selected.

RESULTS AND CONCLUSION: The literature reviewed supported blood lactate monitoring as being useful for risk assessment in patients admitted acutely to hospital, and especially the trend, achieved by serial lactate sampling, is valuable in predicting in-hospital mortality. All patients with a lactate at admission above 2.5 mM should be closely monitored for signs of deterioration, but patients with even lower lactate levels should be considered for serial lactate monitoring. The correlation between lactate levels in arterial and venous blood was found to be acceptable, and venous sampling should therefore be encouraged, as the risk and inconvenience for this procedure is minimal for the patient. The relevance of lactate guided therapy has to be supported by more studies.

[/EXPAND]
3. Lactate clearance vs central venous oxygen saturation as goals of early sepsis therapy: a randomized clinical trial
JAMA. 2010 Feb 24;303(8):739-46
[EXPAND Click for abstract]


CONTEXT: Goal-directed resuscitation for severe sepsis and septic shock has been reported to reduce mortality when applied in the emergency department.

OBJECTIVE: To test the hypothesis of noninferiority between lactate clearance and central venous oxygen saturation (ScvO2) as goals of early sepsis resuscitation.

DESIGN, SETTING, AND PATIENTS: Multicenter randomized, noninferiority trial involving patients with severe sepsis and evidence of hypoperfusion or septic shock who were admitted to the emergency department from January 2007 to January 2009 at 1 of 3 participating US urban hospitals.

INTERVENTIONS: We randomly assigned patients to 1 of 2 resuscitation protocols. The ScvO2 group was resuscitated to normalize central venous pressure, mean arterial pressure, and ScvO2 of at least 70%; and the lactate clearance group was resuscitated to normalize central venous pressure, mean arterial pressure, and lactate clearance of at least 10%. The study protocol was continued until all goals were achieved or for up to 6 hours. Clinicians who subsequently assumed the care of the patients were blinded to the treatment assignment.

MAIN OUTCOME MEASURE: The primary outcome was absolute in-hospital mortality rate; the noninferiority threshold was set at Delta equal to -10%.

RESULTS: Of the 300 patients enrolled, 150 were assigned to each group and patients were well matched by demographic, comorbidities, and physiological features. There were no differences in treatments administered during the initial 72 hours of hospitalization. Thirty-four patients (23%) in the ScvO2 group died while in the hospital (95% confidence interval [CI], 17%-30%) compared with 25 (17%; 95% CI, 11%-24%) in the lactate clearance group. This observed difference between mortality rates did not reach the predefined -10% threshold (intent-to-treat analysis: 95% CI for the 6% difference, -3% to 15%). There were no differences in treatment-related adverse events between the groups.

CONCLUSION: Among patients with septic shock who were treated to normalize central venous and mean arterial pressure, additional management to normalize lactate clearance compared with management to normalize ScvO2 did not result in significantly different in-hospital mortality.

[/EXPAND]
4. Non-septic hyperlactataemia in the emergency department
Emerg Med J. 2010 May;27(5):411-2

Acute Med, All Updates, ICU, Resus

Flumazenil for BZD overdose: getting away with it

Leave a comment

Standard teaching in benzodiazepine (BZD) overdose is that the reversal agent flumazenil is best avoided because of the risk of seizures, particular in those patients who are BZD dependent and those who may have co-ingested proconvulsant substances such as tricyclic antidepressants.
Data from the UK’s National Poisons Information Service indicate that these principles are often flouted in the UK, and they usually get away with it, even in patients who had had seizures prior to flumazenil therapy. This will not change my practice though.


Objective Benzodiazepine (BZD) overdose (OD) continues to cause significant morbidity and mortality in the UK. Flumazenil is an effective antidote but there is a risk of seizures, particularly in those who have co-ingested tricyclic antidepressants. A study was undertaken to examine the frequency of use, safety and efficacy of flumazenil in the management of BZD OD in the UK.

Methods A 2-year retrospective cohort study was performed of all enquiries to the UK National Poisons Information Service involving BZD OD.

Results Flumazenil was administered to 80 patients in 4504 BZD-related enquiries, 68 of whom did not have ventilatory failure or had recognised contraindications to flumazenil. Factors associated with flumazenil use were increased age, severe poisoning and ventilatory failure. Co-ingestion of tricyclic antidepressants and chronic obstructive pulmonary disease did not influence flumazenil administration. Seizure frequency in patients not treated with flumazenil was 0.3%. The frequency of prior seizure in flumazenil-treated patients was 30 times higher (8.8%). Seven patients who had seizures prior to flumazenil therapy had no recurrence of their seizures. Ventilation or consciousness improved in 70% of flumazenil-treated patients. Flumazenil administration was followed by one instance each of agitation and brief seizure.

Conclusions Flumazenil is used infrequently in the management of BZD OD in the UK. It was effective and associated with a low incidence of seizure. These results compare favourably with the results of published randomised controlled trials and cohort studies, although previous studies have not reported the use of flumazenil in such a high-risk population. This study should inform the continuing review of national guidance on flumazenil therapy.

Flumazenil use in benzodiazepine overdose in the UK: a retrospective survey of NPIS data
Emerg Med J. 2012 Jul;29(7):565-9

Acute Med, All Updates, Resus

Emergency physicians providing stroke 'lysis in the UK

Leave a comment

Although the worldwide emergency medicine community is split in its support for stroke thrombolysis, those who work in centres where it is provided might be interested in systems to optimise its effectiveness.
A study from the UK showed that emergency physicians can provide the majority of the service, with outcomes similar to the SITS-MOST data.
Interestingly there was only one (suspected) major intracranial haemorrhage case.
The best resource for reducing door-to-tPA time in ischaemic stroke, with heaps of related discussion, is here at EMCrit

Image from EMJ Open Access. Click for PubMed image source


BACKGROUND: Stroke thrombolysis is strongly supported as an effective therapy for selected cases of early stroke. The absence of 24 h stroke specialists in district general hospitals (DGHs) has led to the suggestion that regional hyper-acute stroke centres should be developed. This paper describes a cooperative model that uses the skills already present in a DGH to deliver a thrombolysis service initiated in the emergency department by the emergency physicians, and describes the outcomes of that service in comparison with the SITS-MOST trial.

METHOD: The outcomes of all stroke patients thrombolysed at Scarborough DGH from 2004 to January 2009 were reviewed. Outcome was defined using a three-part scale. Data at Scarborough DGH were compared with data from the SITS-MOST European-wide study of stroke thrombolysis.

RESULTS: Data were available for 98 of 110 patients thrombolysed during the study period. Fifty (51%) had a good outcome, seven (8%) had partial resolution of their symptoms, and 41 (42%) showed no improvement or deterioration. These outcomes were comparable to those in the European database.

CONCLUSION: Stroke thrombolysis can be effectively delivered in a non-specialist (a non-hyper-acute stroke centre) DGH in the UK. An audit of cases completed describes complications seen.

An analysis of outcomes of emergency physician/department-based thrombolysis for stroke
Emerg Med J. 2012 Aug;29(8):640-3
Free Full Text

Acute Med, All Updates, ICU, Resus

Extracorporeal cardiopulmonary resuscitation

Leave a comment

You have a patient in cardiac arrest who has had excellent resuscitation from the point of collapse, and who has treatable underlying pathology (eg. PE or STEMI). However you’re unable to get return of spontaneous circulation so you call it. Someone just died for whom the technology exists to save them. Extracorporeal life support (ECLS) supports heart and lung function by externally providing circulatory flow and gas exchange until the patient’s underlying cause of arrest is treated or recovers.
ECLS requires an extracorporeal membrane oxygenation (ECMO) circuit to be placed during the cardiac arrest resuscitation. This may sound like extreme stuff, but there have been some amazing saves with this technology, and large numbers of in-hospital and out-of-hospital arrest patients have been treated in Japan, Korea, and Taiwan. ECMO has even been commenced in the field by prehospital emergency physicians.
An inspiring EMCrit podcast with Dr Joe Bellezzo described how this technology is applied at Sharp Memorial Hospital in San Diego. Bellezzo and colleagues have now published a series of their out-of-hospital arrest cases who received ECLS initiated by emergency physicians(1).
Coming back to the Japanese, a multicentre prospective cohort study of ECLS for out-of hospital cardiac arrest (the ‘SAVE-J’ study) selected patients with VF or pulseless VT in whom no ROSC was achieved with standard resuscitative measures. Their striking results mirror other ECLS studies and were published in abstract form in November 2011(2).
To me, the overwhelming take home messages from what I’ve seen and read on this are:


1. ECLS can provide dramatic saves with neurologically intact survival in cardiac arrest cases that otherwise would be dead.

2. The critical factor for successful clinical outcomes and avoidance of wasted resources and clinical futility is case selection. The underlying cause of arrest needs to be reversible (eg. myocarditis) or treatable (eg. STEMI) and good resuscitation needs to have been in place prior to ECLS.

3. In the right hospital with the right resuscitation team, it can be done.

1. Emergency physician-initiated extracorporeal cardiopulmonary resuscitation
Resuscitation. 2012 Aug;83(8):966-70
[EXPAND Click for abstract]


CONTEXT: Extracorporeal cardiopulmonary resuscitation (ECPR) refers to emergent percutaneous veno-arterial cardiopulmonary bypass to stabilize and provide temporary support of patients who suffer cardiopulmonary arrest. Initiation of ECPR by emergency physicians with meaningful long-term patient survival has not been demonstrated.

OBJECTIVE: To determine whether emergency physicians could successfully incorporate ECPR into the resuscitation of patients who present to the emergency department (ED) with cardiopulmonary collapse refractory to traditional resuscitative efforts.

DESIGN: A three-stage algorithm was developed for ED ECPR in patients meeting inclusion/exclusion criteria. We report a case series describing our experience with this algorithm over a 1-year period.

RESULTS: 42 patients presented to our ED with cardiopulmonary collapse over the 1-year study period. Of these, 18 patients met inclusion/exclusion criteria for the algorithm. 8 patients were admitted to the hospital after successful ED ECPR and 5 of those patients survived to hospital discharge neurologically intact. 10 patients were not started on bypass support because either their clinical conditions improved or resuscitative efforts were terminated.

CONCLUSION: Emergency physicians can successfully incorporate ED ECPR in the resuscitation of patients who suffer acute cardiopulmonary collapse. More studies are necessary to determine the true efficacy of this therapy.

[/EXPAND]
2. Multicenter Non-Randomized Prospective Cohort Study of Extracorporeal Cardiopulmonary Resuscitation for Out-of Hospital Cardiac Arrest: Study of Advanced Life Support for Ventricular Fibrillation with Extracorporeal Circulation in Japan (SAVE-J)
Circulation 2011; 124: A18132
[EXPAND Click for abstract]


Background: This study is aimed to examine the efficacy of extracorporeal cardiopulmonary resuscitation (ECPR) for patients in out-of hospital cardiac arrest (OHCA) with ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT).

Method: The design of this study is a multicenter non-randomized prospective cohort study. Hypothesis is that the outcome of OHCA with VF or pulseless VT is similar between ECPR and conventional advanced life support (ALS). During from Oct. 2008 to Dec. 2010, forty six tertiary emergency hospitals were participated in this study. Patient inclusion criteria were 1) VF or pulseless VT on scene, 2) cardiac arrest on arrival at hospital, 3) within 45 minutes from a call to an arrival of hospital, and 4) non-ROSC by conventional ALS during 15 minutes after an arrival at hospital. Exclusion criteria were 1) age: 75 yr, 2) poor activities of daily livings, 3) non-cardiac verified cardiac arrest, and 4) hypothermia. According to the inclusion criteria, ECPR was adopted for OHCA in 26 hospitals (ECPR group) and conventional ALS was planned in 20 hospitals (non-ECPR group). Both groups (Intention-to-treat) were analyzed about the proportion of patients with favorable outcome (CPC1 or 2) assessed with the Glasgow-Pittsburgh Cerebral Performance and Overall Performance Categories at 1 month by chi square test and Fisher exact probability test.

Results: One hundred and eighty patients of ECPR group and 134 patients of non-ECPR group were enrolled. There was no difference between the background of ECPR group and non-ECPR group; Average age (56.0 VS 56.9), Witnessed (72.8% VS 75.4%), Lay-rescuer CPR (49.4% VS 45.5%), Acute coronary syndrome (65.6% VS 61.4%), Minutes from collapse to emergency department (26.8 VS 30.0). The favorable outcome rate in ECPR group (12.4%, 22 patients) was statistically higher than the rate in non-ECPR group (1.6%, two patients) (p<0.001).

Conclusion: Extracorporeal cardiopulmonary resuscitation may improve the outcome of out-of hospital cardiac arrest with VF or pulseless VT without ROSC by conventional ALS during 15 minutes after an arrival at hospital.

[/EXPAND]