Effect of low tidal volume ventilation on atelectasis in patients during general anesthesia: a computed tomographic scan.
OBJECTIVE
To determine whether low tidal ventilation in patients without lung injury results in an increase in the amount of atelectasis and a further impairment of gas exchange during general anesthesia.


METHODS
Randomized, single-blind study.


METHODS
University hospital.


METHODS
16 adult, ASA physical status I and II patients, who were scheduled for elective excision of intracranial lesion.


METHODS
Patients were randomly allocated to one of two groups: traditional tidal volume (V(T)) ventilation group (V(T), 10 mL/kg) and low V(T) ventilation group (V(T), 6 mL/kg) after the first computed tomographic (CT) scan.


RESULTS
Atelectasis, as determined by CT and arterial blood gas analysis, was measured before induction, after tracheal intubation, and at the end of operation. After tracheal intubation, CT scan showed atelectasis in both groups. The mean atelectasis area was 4.25 +/- 2.05 cm(2) (3.32% +/- 1.94%) in the traditional V(T) ventilation group and 5.56 +/- 3.21 cm(2) (4.19% +/- 2.31%) in the low V(T) ventilation group. At the end of operation, there was no significant increase in the amount of atelectasis within the two groups. Arterial blood gas analysis showed no differences after tracheal intubation or at the end of operation in either group.


CONCLUSIONS
Ventilation using low V(T)s does not cause more pulmonary collapse than mechanical ventilation using standard V(T)s.
Cai
Hongwei
H
Department of Anesthesiology and Intensive Care Medicine, Xiangya Hospital, Central Southern University, Changsha, 41008, China.
Gong
Hua
H
Zhang
Lina
L
Wang
Yanjin
Y
Tian
Yuke
Y
D000328:Adult; D000768:Anesthesia, General / Q000379:methods*; D001784:Blood Gas Analysis / Q000379:methods; D001927:Brain Diseases / Q000601:surgery; D017558:Elective Surgical Procedures / Q000379:methods; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D011446:Prospective Studies; D001261:Pulmonary Atelectasis / Q000175:diagnosis* / Q000209:etiology*; D011659:Pulmonary Gas Exchange; D012121:Respiration, Artificial / Q000009:adverse effects* / Q000379:methods; D016037:Single-Blind Method; D013990:Tidal Volume; D014057:Tomography, X-Ray Computed / Q000379:methods*