Comparison between Conventional and Protective One-Lung Ventilation for Ventilator-Assisted Thoracic Surgery

Abstract

Recent papers suggest protective ventilation (PV) as a primary ventilation strategy during one-lung ventilation (OLV) to reduce postoperative pulmonary morbidity. However, data regarding the advantage of the PV strategy in patients with normal preoperative pulmonary function are inconsistent, especially in the case of minimally invasive thoracic surgery. Therefore we compared conventional OLV (V T 10 ml/kg, FiO 2 1.0, zero PEEP) to protective OLV (V T 6 ml/kg, FiO 2 0.5, PEEP 5 cmH 2 O) in patients with normal preoperative pulmonary function tests undergoing video-assisted thoracic surgery. Oxygenation, respiratory mechanics, plasma interleukin-6 and malondialdehyde levels were measured at baseline, 15 and 60 minutes after OLV and 15 minutes after restoration of two-lung ventilation. P a O 2 and P a O 2 /FiO 2 were higher in conventional OLV than in protective OLV (P <0.001). Interleukin-6 and malondialdehyde increased over time in both groups (P <0.05); however, the magnitudes of increase were not different between the groups. Postoperatively there were no differences in the number of patients with P a O 2 /FiO 2 <300 mmHg or abnormalities on chest radiography. Protective ventilation did not provide advantages over conventional ventilation for video-assisted thoracic surgery in this group of patients with normal lung function.

From “awake” to “monitored anesthesia care” thoracic surgery: A 15 year evolution

“…At the dependent lung, OLV induces ventilation‐to‐perfusion mismatch, and promotes further inflammatory changes . Hypoxic environment establishing at the non‐dependent (non‐ventilated) lung causes tissue acidosis, alveolar edema, vascular congestion, cytokine release, and an increased malondialdehyde level.…”

“…Hypoxic environment establishing at the non‐dependent (non‐ventilated) lung causes tissue acidosis, alveolar edema, vascular congestion, cytokine release, and an increased malondialdehyde level. These changes can occur early after minor operations and even in the absence of surgical trauma . At re‐ventilation, high oxygen fraction triggers oxidative burst, leading to neutrophil recruitment and macrophage activation …”

“…At the dependent lung, OLV induces ventilation-to-perfusion mismatch, and promotes further inflammatory changes. [17][18][19][20][21][22][23][24] Hypoxic environment establishing at the non-dependent (non-ventilated) lung causes tissue acidosis, alveolar edema, vascular congestion, [17][18][19] cytokine release, 17 and an increased malondialdehyde level. These changes can occur early after minor operations and even in the absence of surgical trauma.…”

“…These changes can occur early after minor operations and even in the absence of surgical trauma. 24 At re-ventilation, high oxygen fraction triggers oxidative burst, 25,26 leading to neutrophil recruitment [27][28][29][30] and macrophage activation. 31…”

Papel da estratégia protetora de ventilação mecânica na lesão pulmonar induzida pelo ventilador mecânico em pacientes sem síndrome do desconforto respiratório agudo: uma meta-análise de dados individuais de pacientes.

“…Dados de seis estudos não foram coletados devido as seguintes razões: 1) o autor correspondente não pode fornecer os dados ou não tinha mais acesso ao banco de dados (n = 3); 34,36,49 ou 2) o autor correspondente não respondeu a solicitação (n = 3). [50][51][52] Ao final das buscas foram incluídos 2.095 pacientes de 14 estudos randomizados (Tabela 2 e Figura 5). 35,37,38,40,[53][54][55][56][57][58][59][60][61][62] As características dos estudos incluídos estão demonstradas na Tabela 2.…”