[Severe head injuries: effects of pre-hospital mechanical ventilation on capnia].
OBJECTIVE
To assess the effect on PaCO2 of mechanical ventilation during prehospital management of severely head-injured patients.


METHODS
Retrospective observational study.


METHODS
Severely head-injured patients with Glasgow coma score < or = 8. All patients were sedated, with the trachea intubated and the lungs mechanically ventilated.


METHODS
According to the capnia measured at the admission in the neurosurgical intensive therapy unit they were allocated into one of the following three groups: hypocapnia group (PaCO2 < 30 mmHg), recommended capnia group (PaCO2 = 30-38 mmHg) and hypercapnia group (PaCO2 > 38 mmHg).


RESULTS
Out of the 42 patients with similarly severe head injuries, 19% were included in the recommended capnia group (PaCO2: 34 +/- 2 mmHg), 38% in the hypocapnia group (PaCO2: 23 +/- 3 mmHg) and 43% in the hypercapnia group (PaCO2: 47 +/- 7 mmHg). In all except three, PaO2 was above 95 mmHg. The settings of ventilatory parameters on the ventilators were similar.


CONCLUSIONS
In 81% of patients, mechanical ventilation was inadequate as far as PaCO2 levels are concerned. Major hypocapnia and hypercapnia carry a potential risk for cerebral ischaemic. Therefore it is recommended to monitor PETCO2 during prehospital transport in medical ambulances and to determine arterial blood gases at arrival of severely head-injured patients in the admission unit for emergencies.
David
J S
JS
Département d'anesthésie-réanimation VII, Hôpital Edouard-Herriot, Lyon, France.
Cresta
M P
MP
Souab
A
A
Ocquidant
P
P
Petit
P
P
Gueugniaud
P Y
PY
D000293:Adolescent; D000328:Adult; D000368:Aged; D002245:Carbon Dioxide / Q000097:blood*; D006259:Craniocerebral Trauma / Q000097:blood* / Q000503:physiopathology / Q000628:therapy*; D004632:Emergency Medical Services; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D007442:Intubation, Intratracheal; D008297:Male; D008875:Middle Aged; D010313:Partial Pressure; D012121:Respiration, Artificial; D012189:Retrospective Studies
D002245:Carbon Dioxide
Traumatismes crâniens graves: effets de la ventilation mécanique préhospitalière sur la capnie.