Oxygénothérapie hyperbare et gaz inertes dans l’ischémie cérébrale et le traumatisme crânien

Cerebral ischemia is a common thread of acute cerebral lesions, whether vascular or traumatic origin. Hyperbaric oxygen (HBO) improves tissue oxygenation and may prevent impairment of reversible lesions. In experimental models of cerebral ischemia or traumatic brain injury, HBO has neuroprotective effects which are related to various mechanisms such as modulation of oxidative stress, neuro-inflammation or cerebral and mitochondrial metabolism. However, results of clinical trials failed to prove any neuroprotective effects for cerebral ischemia and remained to be confirmed for traumatic brain injury despite preliminary encouraging results. The addition of inert gases to HBO sessions, especially argon or xenon which show neuroprotective experimental effects, may provide an additional improvement of cerebral lesions. Further multicentric studies with a strict methodology and a better targeted definition are required before drawing definitive conclusions about the efficiency of combined therapy with HBO and inert gases in acute cerebral lesions.     

Variation de kaliémie après une induction en séquence rapide avec la succinylcholine chez les patients de réanimation

Objective

Evaluate the changes in potassium following rapid sequence induction with succinylcholine in critically ill-patients and determine whether hospital length of stay could influence the succinylcholine-induced hyperkaliemia.

Study design

Prospective and observational study.

Patients and methods

After approval by our local ethical committee, we prospectively included 36 patients admitted from more than 24 hours in ICU and who required succinylcholine for rapid tracheal intubation (1 mg/kg). Serum potassium was measured before, 5 and 30 min after succinylcholine. The incidence of life-threatening hyperkaliemia (≥ 6.5 mmol/L) was noted.

Results

We could observe significant and transient increase in serum potassium (median increase of 0.45 [0.20–0.80] mmol/L at five minutes). A significant relationship was observed between the ICU length of stay and arterial potassium increase (r = 0.37, P < 0.05). From the ROC curve, a threshold of 12 days had an 86% sensitivity and 69% specificity in discriminating patients in whom the potassium increase was more than 1.5 mmol/L.

Conclusion

Induction with succinylcholine is followed by significant but transient hyperkaliema. The ICU length of stay before giving succinylcholine could influence significantly the amplitude of potassium increase.     

Hématome rétroplacentaire

Retroplacental haematoma (RPH) is a complication affecting 0.25 to 0.4% of all pregnancies and 4% of severe PEs. It is of acute onset, usually unpredictable and its symptoms are not specific: Isolated metrorrhagia, foetal distress, uterine hypertonicity. Clinical, biological and sonographic features suggesting a RPH can be early or late. Haemoconcentration and the forming of notches on Doppler examination of the uterus can appear weeks before the event, whereas raised D-Dimers and foetal tachycardia are identified within days of the event. Although Caesarian section reduces the perinatal death rate by 20 to 50% in a setting of RPH with a live foetus, vaginal delivery is indicated in cases of RPH with fetal demise, following the control of haemorrhagic shock, clotting disorders and uterine hypotonicity.