Assessing the impact of lung hyperinflation maneuver on systemic inflammatory response and lung collapse in patients undergoing surgeries under spontaneous ventilation.
OBJECTIVE
Lung hyperinflation maneuvers (LHM) reverse intraoperative atelectasis; however, they can lead to pulmonary-induced systemic inflammatory response. The objective of this study was to determine the impact of LHM on systemic inflammatory response and lung structure in patients undergoing subarachnoid block.


METHODS
After approval by the Ethics Committee of the institution and signing the informed consent, 20 patients undergoing small and medium surgical procedures were randomly separated into two groups: 1) control (CG), and 2) LHM (LHMG). One hour after the spinal anesthesia, LHM was performed in LHMG by applying bilevel positive pressure in the airways (BIPAP) with an expiratory pressure of 20 cmH(2)O and inspiratory pressure of 20 cmH(2)O for 1 to 2 minutes. Blood levels of TNFalpha, IL-1, IL-6, IL-8, IL-10, and IL-12 were determined by flow cytometry at baseline and at 90, 180, and 780 minutes. Lung volumes and weights were determined using CT scans obtained immediately after the surgery.


RESULTS
The use of LHM resulted in a reduction in the fraction of non-aerated pulmonary parenchyma (7.5 +/- 4.3%, in the Control Group, vs. 4 +/- 2.1%, in the LHM Group, p = 0.02) without changing pulmonary volumes. A progressive increase in plasma levels of IL-1, IL-6, IL-8, and IL-10, similar in both groups, was observed. Plasma levels of TNFalpha and IL-12 were undetectable during the study.


CONCLUSIONS
The use of LHM reduced the incidence of atelectasis, but it did not amplify the inflammatory response in patients with normal lungs undergoing small and medium surgeries under subarachnoid block.
Malbouisson
Luiz Marcelo Sá
LM
Hospital das Clínicas (HC) of the Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brasil. malbouisson@hcnet.usp.br
de Souza
Elton Lúcio Silva
EL
Barbalho
Larissa
L
Massoco
Cristina de Oliveira
Cde O
Carmona
Maria José Carvalho
MJ
Auler
José Otávio Costa
JO
D000775:Anesthesia, Spinal; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000209:etiology* / Q000473:pathology; D007431:Intraoperative Complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D001261:Pulmonary Atelectasis / Q000097:blood / Q000473:pathology / Q000628:therapy*; D012138:Respiratory Therapy / Q000009:adverse effects*; D013514:Surgical Procedures, Operative