Background: The use of lung-protective ventilation (LPV) strategies may minimize iatrogenic lung injury in surgical patients. However, the identification of an ideal LPV strategy, particularly during one-lung ventilation (OLV), remains elusive. This study examines the role of ventilator management during OLV and its impact on clinical outcomes.

Methods: Data were retrospectively collected from the hospital electronic medical record and the Society of Thoracic Surgery database for subjects undergoing thoracic surgery with OLV between 2012 and 2014. Mean tidal volume (VT) during two-lung ventilation and OLV and ventilator driving pressure ([DELTA]P) (plateau pressure – positive end-expiratory pressure [PEEP]) were analyzed for the 1,019 cases that met the inclusion criteria. Associations between ventilator parameters and clinical outcomes were examined by multivariate linear regression.

Results: After the initiation of OLV, 73.3, 43.3, 18.8, and 7.2% of patients received VT greater than 5, 6, 7, and 8 ml/kg predicted body weight, respectively. One hundred and eighty-four primary and 288 secondary outcome events were recorded. In multivariate logistic regression modeling, VT was inversely related to the incidence of respiratory complications (odds ratio, 0.837; 95% CI, 0.729 to 0.958), while [DELTA]P predicted the development of major morbidity when modeled with VT (odds ratio, 1.034; 95% CI, 1.001 to 1.068).

Conclusions: Low VT per se (i.e., in the absence of sufficient PEEP) has not been unambiguously demonstrated to be beneficial. The authors found that a large proportion of patients continue to receive high VT during OLV and that VT was inversely related to the incidence of respiratory complications and major postoperative morbidity. While low (physiologically appropriate) VT is an important component of an LPV strategy for surgical patients during OLV, current evidence suggests that, without adequate PEEP, low VT does not prevent postoperative respiratory complications. Thus, use of physiologic VT may represent a necessary, but not independently sufficient, component of LPV.

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BACKGROUND: Lung resection surgery is associated with an inflammatory reaction. The use
of 1-lung ventilation (OLV) seems to increase the likelihood of this reaction. Different prophylactic
and therapeutic measures have been investigated to prevent lung injury secondary to OLV.
Lidocaine, a commonly used local anesthetic drug, has antiinflammatory activity. Our main goal
in this study was to investigate the effect of IV lidocaine on tumor necrosis factor α (TNF-α) lung
expression during lung resection surgery with OLV.
METHODS: Eighteen pigs underwent left caudal lobectomy. The animals were divided into 3
groups: control, lidocaine, and sham. All animals received general anesthesia. In addition, animals
in the lidocaine group received a continuous IV infusion of lidocaine during surgery (1.5
mg/kg/h). Animals in the sham group only underwent thoracotomy. Samples of bronchoalveolar
lavage (BAL) fluid and plasma were collected before initiation of OLV, at the end of OLV, at the
end of surgery, and 24 hours after surgery. Lung biopsy specimens were collected from the left
caudal lobe (baseline) before surgery and from the mediastinal lobe and the left cranial lobe
24 hours after surgery. Samples were flash-frozen and stored to measure levels of the following
inflammatory markers: interleukin (IL) 1β, IL-2, IL-10, TNF-α, nuclear factor κB, monocyte chemoattractant
protein-1, inducible nitric oxide synthase, and endothelial nitric oxide synthase.
Markers of apoptosis (caspase 3, caspase 9, Bad, Bax, and Bcl-2) were also measured. In addition,
levels of metalloproteinases and nitric oxide metabolites were determined in BAL fluid and
in plasma samples. A nonparametric test was used to examine statistical significance.
RESULTS: OLV caused lung damage with increased TNF-α expression in BAL, plasma, and lung
samples. Other inflammatory (IL-1β, nuclear factor κB, monocyte chemoattractant protein-1)
and apoptosis (caspase 3, caspase 9, and BAX) markers were also increased. With the use
of IV lidocaine there was a significant decrease in the levels of TNF-α in the same samples
compared with the control group. Lidocaine administration also reduced the inflammatory and
apoptotic changes observed in the control group. Hemodynamic values, blood gas values, and
airway pressure were similar in all groups.
CONCLUSIONS: Our results suggest that lidocaine can prevent OLV-induced lung injury through
reduced expression of proinflammatory cytokines and lung apoptosis. Administration of lidocaine
may help to prevent lung injury during lung surgery with OLV. (Anesth Analg 2014;119:815–28)

Background. Transthoracic oesophagectomy requires prolonged one-lung ventilation causing
systemic and local inflammatory responses. Application of continuous positive airway
pressure (CPAP) to the collapsed lung potentially reduces pulmonary damage, hypoxia, and
consequent inflammation. This randomized controlled trial studied the influence of CPAP
applied to the collapsed right lung during thoracoscopic oesophagectomy on local and
systemic inflammatory response.
Methods. Broncho-alveolar lavage fluid (BALF) fromthe right collapsedandleft ventilated lung
and serum samples were obtained during surgery from 30 patients undergoing
thoracolaparoscopic oesophagectomy for cancer who were randomized for one-lung
ventilation with or without CPAP applied to the collapsed right lung. Concentrations of
cytokines and chemokines, in BALF and serum, were determined with Luminex.
Results. Patients fromthe control (no CPAP) group had significantly increased concentrations of
interleukin (IL)-1a, IL-1b, IL-10, tumour necrosis factor-alpha, macrophage inflammatory
protein (MIP)-1a, pulmonary and activation-regulated chemokine (PARC), and IL-8 in the
collapsed (right) lung when compared with patients from the CPAP group (P,0.05). The
ventilated (left) lung of the control group showed increased concentrations of monocyte
chemoattractant protein (MCP)-1 and MIP-1a (P,0.05). Serum concentrations of cytokines
and chemokines increased during surgery, but did not differ between the control and CPAP
groups.
Conclusions. A significantly lower local immune response was observed during one-lung
ventilation when CPAP was applied to the collapsed lung. The findings suggest a beneficial
effect of CPAP on the collapsed lung during oesophagectomy with one-lung ventilation

AB Background This is an update of a Cochrane Review first published in The Cochrane Library, Issue 2, 2008. Objectives The objective of this review was to evaluate the effectiveness and safety of intravenous versus inhalation anaesthesia for one-lung ventilation. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL); The Cochrane Library (2012, Issue 11); MEDLINE (1966 to November 2012); EMBASE (1980 to November 2012); Literatura Latino-Americana e do Caribe em Ciencias da Saude (LILACS, 1982 to November 2012) and ISI web of Science (1945 to November 2012), reference lists of identified trials and bibliographies of published reviews. We also contacted researchers in the field. No language restrictions were applied. The date of the most recent search was 19 November 2012. The original search was performed in June 2006. Selection criteria We included randomized controlled trials and quasi-randomized controlled trials of intravenous (e.g. propofol) versus inhalation (e.g. isoflurane, sevoflurane, desflurane) anaesthesia for one-lung ventilation in both surgical and intensive care participants. We excluded studies of participants who had only one lung (i.e. pneumonectomy or congenital absence of one lung). Data collection and analysis Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information. Main results We included in this updated review 20 studies that enrolled 850 participants, all of which assessed surgical participants[FULLWIDTH HYPHEN-MINUS]no studies investigated one-lung ventilation performed outside the operating theatre. No evidence indicated that the drug used to maintain anaesthesia during one-lung ventilation affected participant outcomes. The methodological quality of the included studies was difficult to assess as it was reported poorly, so the predominant classification of bias was ‘unclear’. Authors’ conclusions Very little evidence from randomized controlled trials suggests differences in participant outcomes with anaesthesia maintained by intravenous versus inhalational anaesthesia during one-lung ventilation. If researchers believe that the type of drug used to maintain anaesthesia during one-lung ventilation is important, they should design randomized controlled trials with appropriate participant outcomes, rather than report temporary fluctuations in physiological variables.

Background. This study was conducted to determine whether an alveolar recruitment
strategy (ARS) applied during two-lung ventilation (TLV) just before starting one-lung
ventilation (OLV) improves ventilatory efficiency.
Methods. Subjects were randomly allocated to two groups: (i) control group: ventilation with
tidal volume (VT) of 8 or 6 ml kg21 for TLV and OLV, respectively, and (ii) ARS group: same
ventilatory pattern with ARS consisting of 10 consecutive breaths at a plateau pressure of
40 and 20 cm H2O PEEP applied immediately before and after OLV. Volumetric capnography
and arterial blood samples were recorded 5 min (baseline) and 20 min into TLV, at 20 and
40 min during OLV, and finally 10 min after re-establishing TLV.
Results. Twenty subjects were included in each group. In all subjects, the airway
component of dead space remained constant during the study. Compared with baseline,
the alveolar dead space ratio (VDalv/VTalv) increased throughout the protocol in the
control but decreased in the ARS group. Differences in VDalv/VTalv between groups were
significant (P,0.001). Except for baseline, all PaO2 values in kPa (SD) were higher in the
ARS than in the control group (P,0.001), respectively [70 (7) and 55 (9); 33 (9) and 24
(10); 33 (8) and 22 (10); 70 (7) and 55 (10)].
Conclusions. Recruitment of both lungs before instituting OLV not only decreased alveolar
dead space but also improved arterial oxygenation and the efficiency of ventilation.
Keywords: lung, atelectasis; lung, gas exchange; surgery, thoracic; ventilation, dead space;
ventilation, one-lung ventilation

Background: The increased tidal volume (VT) applied tothe ventilated lung during one-lung ventilation (OLV) enhancescyclic alveolar recruitment and mechanical stress. It isunknown whether alveolar recruitment maneuvers (ARMs)and reduced VT may influence tidal recruitment and lungdensity. Therefore, the effects of ARM and OLV with differentVT on pulmonary gas/tissue distribution are examined.Methods: Eight anesthetized piglets were mechanically ventilated(VT 10 ml/kg). A defined ARM was applied to thewhole lung (40 cm H2O for 10 s). Spiral computed tomographiclung scans were acquired before and after ARM.Thereafter, the lungs were separated with an endobronchialblocker. The pigs were randomized to receive OLV in thedependent lung with aVT of either 5 or 10 ml/kg. Computedtomography was repeated during and after OLV. The voxelswere categorized by density intervals (i.e., atelectasis, poorlyaerated, normally aerated, or overaerated). Tidal recruitmentwas defined as the addition of gas to collapsed lung regions.Results: The dependent lung contained atelectatic (5610 ml),poorly aerated (18310 ml), and normally aerated (18729 ml)regions before ARM. After ARM, lung volume and aeration increased(42635 vs. 52669 ml). Respiratory compliance enhanced,and tidal recruitment decreased(95%vs.79%of the wholeend-expiratory lung volume).OLVwith10ml/kgfurther increasedaeration (atelectasis, 152 ml; poorly aerated, 9424 ml; normallyaerated, 580 98 ml) and tidal recruitment (81% of thedependent lung). OLV with 5 ml/kg did not affect tidal recruitmentor lung density distribution. (Data are given as meanSD.)Conclusions: The ARM improves aeration and respiratorymechanics. In contrast to OLV with high VT, OLV withreduced VT does not reinforce tidal recruitment, indicatingdecreased mechanical stress.

Background: Protective ventilation strategy has been shown to reduce ventilator-induced
lung injury in ARDS patients. In this study, we questioned whether protective ventilatory
settings would attenuate lung impairment during one lung ventilation (OLV) compared to
conventional ventilation in patients undergoing lung resection surgery.
Methods: One hundred ASA 1-2 patients scheduled for an elective lobectomy were
enrolled in the study. During OLV, two different ventilation strategies were compared. The
conventional strategy (CV group, n=50) consisted of FiO2 1.0, VT 10 ml/kg, ZEEP, and
volume-controlled ventilation, while the protective strategy (PV group, n=50) consisted of
FiO2 0.5, VT 6 ml/kg, PEEP 5 cm H2O, and pressure-controlled ventilation. The composite
primary endpoint included, PaO2/FiO2 < 300 mmHg and/or the presence of newly developed lung lesions (lung infiltration and atelectasis) within 72 hours of the operation. To monitor safety during OLV, SpO2, PaCO2, and PIP were repeatedly measured. Results: During OLV, although 58% of the PV group needed elevated FiO2 to maintain an SpO2 above 95%, PIP was significantly lower than in the CV group whereas the mean PaCO2 values remained at 35-40 mmHg in both groups. Importantly, in the PV group, the incidence of the primary endpoint of pulmonary dysfunction was significantly lower than in the CV group (the incidence of PaO2/FiO2 < 300 mmHg, lung infiltration, or atelectasis : 4% vs. 22%, P < 0.05). Conclusion: Compared with the traditional large VT and volume-controlled ventilation, the application of small VT and PEEP through pressure-controlled ventilation was associated with a lower incidence of postoperative lung dysfunction and satisfactory gas exchange.

Background. Pressure-controlled ventilation (PCV) has been suggested to reduce peak
airway pressure (Ppeak) and intrapulmonary shunt during one-lung ventilation (OLV) when
compared with volume-controlled ventilation (VCV). At the same tidal volume (VT), the
apparent difference in Ppeak is mainly related to the presence of a double-lumen tracheal
tube. We tested the hypothesis that the decrease in Ppeak observed in the breathing
circuit is not necessarily associated with a decrease in the bronchus of the dependent lung.
Methods. This observational study included 15 consecutive subjects who were ventilated
with VCV followed by PCV at constant VT. Airway pressure was measured simultaneously in
the breathing circuit and main bronchus of the dependent lung after 20 min of ventilation.
Results. PCV induced a significant decrease in Ppeak [mean (SD)] measured in the breathing
circuit [36 (4) to 26 (3) cm H20, P,0.0001] and in the bronchus [23 (4) to 22 (3) cm H2O,
P¼0.01]. However, the interaction (ventilatory mode × site of measurement) revealed that
the decrease in Ppeak was significantly higher in the circuit (P,0.0001). Although the mean
percentage decrease in Ppeak was significant at both sites, the decrease was significantly
lower in the bronchus [5 (6)% vs 29 (3)%, P,0.0001].
Conclusions. During PCV for OLV, the decrease in Ppeak is observed mainly in the respiratory
circuit and is probably not clinically relevant in the bronchus of the dependent lung. This
challenges the common clinical perception that PCV offers an advantage over VCV during
OLV by reducing bronchial Ppeak.

We used inhaled epoprostenol (with intravenous phenylephrine)
during one-lung ventilation to improve oxygenation
in a patient with severe interstitial lung disease
undergoing video-assisted thoracoscopic surgery. The
pharmacologic manipulation of pulmonary blood flow
remains an underused strategy for the management of
hypoxemia during one-lung ventilation.