How to Be a Hero

Kal-fly-iconI’m not a hero and don’t claim to be, but when I was given this talk to do for the SMACC 2013 conference I researched the topic and realised I’d worked with several of them.

The talk was the toughest I’ve ever given, because I cried while giving it, and knew that it wouldn’t just be the large audience in front of me who would know I was a wuss, but that it was being recorded for many others to find out too!

A full transcript of the talk, the slide set, and links to references from the talk can be found here.

Early surgery for intracerebral haemorrhage

ICHgraphicIconTo operate or not to operate on patients with an intracerebral haematoma? Deep ones can be tricky and risk damage to surrounding brain, so superficial ones may be more likely to benefit.

These patients with superficial lesions were assessed in STICH II, an international prospective randomised controlled trial comparing early surgery with conservative treatment.

Inclusion criteria were strict:

  • spontaneous lobar intracerebral haemorrhage on CT scan (≤1 cm from the cortical surface of the brain) with a volume of between 10 mL and 100 mL
  • within 48 h of onset
  • had a best motor score on the Glasgow Coma Score (GCS) of 5 or 6, and had a best eye score of 2 or more (ie, were conscious at randomisation).

The primary outcome was a Glasgow Outcome Scale-based evaluation of recovery (‘favourable’ vs ‘unfavourable’), which did not significantly differ between groups.

A predefined subgroup of patients with a poorer prognosis (using a score based on age, haematoma size and GCS) may have a better outcome with surgery. Some patients randomised to conservative therapy subsequently underwent delayed surgery. Thanks to appropriate intention-to-treat analysis they would have remained in the conservative treatment group which may have contributed to an underestimation of the benefit of surgery.

So, overall a negative trial, and patients with small lesions and higher GCS scores won’t benefit from surgery. Patients in poorer prognostic groups might benefit, but that remains unproven.

Some other ICH trials to be aware of are Clear III and MISTIE III, which are investigating thrombolytic agents in combination with clot removal, including with minimally invasive techniques.

Early surgery versus initial conservative treatment in patients with spontaneous supratentorial lobar intracerebral haematomas (STICH II): a randomised trial
Lancet. 2013 Aug 3;382(9890):397-408


BACKGROUND: The balance of risk and benefit from early neurosurgical intervention for conscious patients with superficial lobar intracerebral haemorrhage of 10-100 mL and no intraventricular haemorrhage admitted within 48 h of ictus is unclear. We therefore tested the hypothesis that early surgery compared with initial conservative treatment could improve outcome in these patients.

METHODS: In this international, parallel-group trial undertaken in 78 centres in 27 countries, we compared early surgical haematoma evacuation within 12 h of randomisation plus medical treatment with initial medical treatment alone (later evacuation was allowed if judged necessary). An automatic telephone and internet-based randomisation service was used to assign patients to surgery and initial conservative treatment in a 1:1 ratio. The trial was not masked. The primary outcome was a prognosis-based dichotomised (favourable or unfavourable) outcome of the 8 point Extended Glasgow Outcome Scale (GOSE) obtained by questionnaires posted to patients at 6 months. Analysis was by intention to treat. This trial is registered, number ISRCTN22153967.

FINDINGS: 307 of 601 patients were randomly assigned to early surgery and 294 to initial conservative treatment; 298 and 291 were followed up at 6 months, respectively; and 297 and 286 were included in the analysis, respectively. 174 (59%) of 297 patients in the early surgery group had an unfavourable outcome versus 178 (62%) of 286 patients in the initial conservative treatment group (absolute difference 3·7% [95% CI -4·3 to 11·6], odds ratio 0·86 [0·62 to 1·20]; p=0·367).

INTERPRETATION: The STICH II results confirm that early surgery does not increase the rate of death or disability at 6 months and might have a small but clinically relevant survival advantage for patients with spontaneous superficial intracerebral haemorrhage without intraventricular haemorrhage.

GOLDen Educational Opportunity!

smacc-gold-logo-2

 

SMACC was my all-time favourite conference ever. Its sequel, smaccGOLD, promises to be even better, as you’ll see from the program

The smaccGOLD online registration goes live this Monday 16th September at 8am in Sydney

This will be 11pm Sunday 15th in London, and 6pm Sunday 15th in New York

Make sure you don’t miss your chance to register for the best critical care conference ever!

Also check out the preconference workshops – a jawdropping line-up of medical masters covering everything you’d want to learn. The only difficult part is deciding what you won’t go to! Places are limited and expected will sell out quickly. Registration is on a first come basis.

Hopefully we’ll see you there.

smaccGOLD is a not-for-profit venture and I receive no payment for any participation in the conference or its promotion

Beta blockade in sepsis

tachy-iconWhat do septic patients need if they remain shocked after fluid resuscitation? Catecholamines right? Let’s stimulate some adrenoceptors and support that circulation!

Sydney’s Prof Myburgh has told us why adrenaline (epinephrine) and noradrenaline (norepinephrine) are the go-to vasoactive choices, and Prof Singer from London likes to remind us about the detrimental effects of these drugs – the pros and cons are listed here. Tachycardia is associated with worse outcomes in sepsis, and the balance of oxygen supply and demand can be difficult to achieve. Beta blocking drugs could reduce tachycardia, but there does seem to be something counter-intuitive about giving both beta-blockers and catecholamines in the same patient. You might expect that beta blockers would cause fall in cardiac output and worsen tissue perfusion.

A small study previously showed possible helpful effects of beta blockers in children with burns. The potential benefits may extend beyond control of heart rate to anti-inflammatory / anti-catabolic effects. A recent publication evaluated beta blockers in adult patients with septic shock, which appears to be a pilot study for an ongoing randomised controlled trial.

They included patients who had been fluid resuscitated and who required noradrenaline, and treated them with a titrated esmolol infusion commenced at 25 mg/hr, with an upper dose limit of 2,000 mg/hr, to maintain a predefined HR range between 80 and 94 beats per minute. Esmolol was chosen because of its half-life of approximately 2 min, so any adverse effects could be rapidly reversed. They examined the macrocirculation using pulmonary artery catheterisation and the microcirculation using sublingual microvascular blood flow imaging.

Most of the patients had pneumonia, and interestingly, all patients received intravenous hydrocortisone (200mg/d) as a continuous infusion.

In this small cohort of patients, they found that titrating the heart rate to less than 95 bpm was associated with maintenance of stroke volume and preservation of microvascular blood flow. Although cardiac output fell because of the lower HR, stroke volume, MAP, and lactate levels were unchanged while noradrenaline requirements were reduced.

Increased vascular reactivity to norepinephrine following nonselective β-blockade is supported by volunteer and animal studies, and postulated mechanisms include:
  • blockade of a peripheral β2-mediated vasodilatory effect of noradrenaline
  • decreased clearance of infused noradrenaline
  • a centrally mediated effect on reflex activity
  • inhibition of vascular endothelial nitric oxide synthase activity

Microvascular Effects of Heart Rate Control With Esmolol in Patients With Septic Shock: A Pilot Study
Crit Care Med. 2013 Sep;41(9):2162-2168


 

OBJECTIVE: β-blocker therapy may control heart rate and attenuate the deleterious effects of β-stimulating catecholamines in septic shock. However, their negative chronotropy and inotropy may potentially lead to an inappropriately low cardiac output, with a subsequent compromise of microvascular blood flow. The purpose of the present pilot study was to investigate the effects of reducing heart rate to less than 95 beats per minute in patients with septic shock using the β-1 adrenoceptor blocker, esmolol, with specific focus on systemic hemodynamics and the microcirculation.

DESIGN: Prospective, observational clinical study.

SETTING: Multidisciplinary ICU at a university hospital.

MEASUREMENTS AND MAIN RESULTS: After 24 hours of initial hemodynamic optimization, 25 septic shock patients with a heart rate greater than or equal to 95 beats per minute and requiring norepinephrine to maintain mean arterial pressure greater than or equal to 65 mm Hg received a titrated esmolol infusion to maintain heart rate less than 95 beats per minute. Sublingual microcirculatory blood flow was assessed by sidestream dark-field imaging. All measurements, including data from right heart catheterization and norepinephrine requirements, were obtained at baseline and 24 hours after esmolol administration. Heart rates targeted between 80 and 94 beats per minute were achieved in all patients. Whereas cardiac index decreased (4.0 [3.5; 5.3] vs 3.1 [2.6; 3.9] L/min/m; p < 0.001), stroke volume remained unchanged (34 [37; 47] vs 40 [31; 46] mL/beat/m; p = 0.32). Microcirculatory blood flow in small vessels increased (2.8 [2.6; 3.0] vs 3.0 [3.0; 3.0]; p = 0.002), while the heterogeneity index decreased (median 0.06 [interquartile range 0; 0.21] vs 0 [0; 0]; p = 0.002). PaO2 and pH increased while PaCO2 decreased (all p < 0.05). Of note, norepinephrine requirements were significantly reduced by selective β-1 blocker therapy (0.53 [0.29; 0.96] vs 0.41 [0.22; 0.79] µg/kg/min; p = 0.03).

CONCLUSIONS: This pilot study demonstrated that heart rate control by a titrated esmolol infusion in septic shock patients was associated with maintenance of stroke volume, preserved microvascular blood flow, and a reduction in norepinephrine requirements.