Neurocritical care (NCC) is not only generally guided by principles of general intensive care, but also directed by specific goals and methods. This review summarizes the common pulmonary diseases and pathophysiology affecting NCC patients and the progress made in strategies of respiratory support in NCC. This review highlights the possible interactions and pathways that have been revealed between neurological injuries and respiratory diseases, including the catecholamine pathway, systemic inflammatory reactions, adrenergic hypersensitivity, and dopaminergic signaling. Pulmonary complications of neurocritical patients include pneumonia, neurological pulmonary edema, and respiratory distress. Specific aspects of respiratory management include prioritizing the protection of the brain, and the goal of respiratory management is to avoid inappropriate blood gas composition levels and intracranial hypertension. Compared with the traditional mode of protective mechanical ventilation with low tidal volume (Vt), high positive end-expiratory pressure (PEEP), and recruitment maneuvers, low PEEP might yield a potential benefit in closing and protecting the lung tissue. Multimodal neuromonitoring can ensure the safety of respiratory maneuvers in clinical and scientific practice. Future studies are required to develop guidelines for respiratory management in NCC.
Humans ; Lung ; Lung Diseases/etiology* ; Positive-Pressure Respiration/methods* ; Respiration, Artificial/adverse effects* ; Tidal Volume

Cardiac Surgical Procedures ; adverse effects ; Humans ; Positive-Pressure Respiration ; methods ; Respiratory Insufficiency ; therapy

OBJECTIVETo investigate the effect of pentoxifylline on one-lung ventilation injury in rabbits.

METHODSTwenty rabbit models of one-lung ventilation by intrabronchial intubation after tracheotomy were randomly allocated in control group (with one-lung ventilation) and experiment group (with one-lung ventilation and intravenous pentoxifylline administration). One-lung ventilation was maintained for 3 h in both groups using the volume-control mode (tidal volume of 8 ml/kg at the frequency of 30 per min). Arterial blood samples were taken after anesthesia and at 3 h of one-lung ventilation for arterial blood gas analysis to obtain the oxygenation index. At the end of the experiment, the pulmonary wet/dry ratio (W/D), tumor necrosis factor-alpha (TNF-alpha), NO, malondialdehyde (MDA) and superoxide dismutase (SOD) contents in bronchoalveolar lavage fluid (BALF) were measured and the histological appearance of the lung tissue was observed.

RESULTSThe oxygenation index was significantly higher (P<0.05), W/D ratio lower (P<0.05), and contents of TNF-alpha, NO and MAD in the BALF lower in the experimental group than in the control group (P<0.05). The activity of SOD increased significantly in the experimental group as compared with the control group (P<0.01), and the rabbits in the experimental group showed milder pathological changes.

CONCLUSIONIntravenous pentoxifylline may improve pulmonary ventilation function and alleviate pulmonary injury, thus offering protection against pulmonary injury after one-lung ventilation.

Acute Lung Injury ; etiology ; prevention & control ; Animals ; Continuous Positive Airway Pressure ; methods ; Female ; Intubation, Intratracheal ; Male ; Pentoxifylline ; pharmacology ; Pulmonary Ventilation ; Rabbits ; Respiration, Artificial ; adverse effects ; methods

OBJECTIVETo study clinical effectiveness and possible side effects of lower tidal volume combine with lung recruitment on acute respiratory distress syndrome (ARDS) for post operative esophageal carcinoma surgery patients.

METHODSTwenty six hypoxemie post operative esophageal carcinoma surgery patients from Cancer Hospital and Peking Union Medical College Hospital were included from 1st January 2007 to 30th September 2009. There were 20 male and 6 female with an average age of 65.5 years (51 - 76 years). Circulation was stable among them. They could not weaned from mechanical ventilation due to ARDS. Bedside monitoring included noninvasive continuous artery blood pressure (NBP), pulse oximetry saturation (SPO2). Patients were ventilated on volume control mode. Tidal volumes set to 6 ml/kg. Recruitment maneuvers were conducted by stepwise rising of positive end expiratory pressure (PEEP) level. PEEP, fraction of inspired oxygen (FiO2), static compliance of lung (CLS) and arterial blood gas analysis (ABG) before and at 30 min after each of twice applying recruitment maneuvers were measured.

RESULTSFifty-two recruitments were completed on these 26 cases. PaO2/FiO2 improved significantly in 26 cases. The level of FiO2 were significantly lowered, CLS were increased significantly 30 min after each of twice applying recruitment maneuvers in all 26 cases. No complication was encountered. All patients were discharged successfully.

CONCLUSIONHypoxemia of ARDS following esophageal carcinoma surgery can be improved by lower tidal volume combine with lung recruitment maneuver.

Aged ; Esophageal Neoplasms ; surgery ; Female ; Humans ; Male ; Middle Aged ; Positive-Pressure Respiration ; Postoperative Complications ; therapy ; Respiration, Artificial ; adverse effects ; methods ; Respiratory Distress Syndrome, Adult ; etiology ; therapy ; Thoracotomy ; adverse effects ; Tidal Volume ; Treatment Outcome

OBJECTIVETo observe and compare the effects of two kinds of lung recruitment maneuvers, namely sustained inflation (SI) and incremental positive end-expiratory pressure (PEEP) (IP) on oxygenation, respiratory mechanics, and hemodynamics of dogs with severe smoke inhalation injury.

METHODSAfter being treated with conventional mechanical ventilation, 12 dogs were inflicted with severe smoke inhalation injury. They were divided into group SI and group IP according to the random number table, with 6 dogs in each group. Dogs in group SI were subjected to continuous positive airway pressure ventilation, with inspiratory pressure of 25 cmH2O (1 cmH2o = 0. 098 kPa), and it was sustained for 20 s. PEEP level in group IP was gradually increased by 5 cmH2O every 5 min up to 25 cmH2O, and then it was decreased by 5 cmH2O every 5 min until reaching 2-3 cmH2O. Then the previous ventilation mode was resumed in both groups for 8 hours. Blood gas analysis (pH value, PaO2, and PaCO2), oxygenation index (OI), respiratory mechanics parameters [peak inspiratory pressure (PIP), mean airway pressure, and dynamic lung compliance], and hemodynamic parameters [heart rate, mean arterial pressure (MAP), pulmonary arterial pressure (PAP), and cardiac output (CO)] were recorded or calculated before injury, immediately after injury, and at post ventilation hour (PVH) 2, 4, 6, 8. Data were processed with analysis of variance of repeated measurement and LSD-t test.

RESULTS(1) At PVH 6 and 8, pH values of dogs in group SI were significantly lower than those in group IP (with t values respectively 2. 431 and 2. 261, P values below 0.05); PaO2 levels in group SI [(87 ± 24), (78 ± 14) mmHg, 1 mmHg =0. 133 kPa] were lower than those in group IP [ (114 ± 18) , (111 ± 17) mmHg, with t values respectively 2. 249 and 3.671, P <0.05 or P <0.01]; OI values in group SI were significantly higher than those in group IP (with t values respectively 2.363 and 5.010, P <0.05 or P <0.01). No significant differences were observed in PaCO2 level within each group or between the two groups (with t values from 0. 119 to 1. 042, P values above 0.05). Compared with those observed immediately after injury, the pH values were significantly lowered (except for dogs in group IP at PVH 6 and 8, with t values from 2.292 to 3.222, P <0.05 or P <0.01), PaO2 levels were significantly elevated (with t values from 4. 443 to 6.315, P <0.05 or P <0.01), and OI values were significantly lowered (with t values from 2.773 to 9.789, P <0.05 orP <0.01) in both groups at all the treatment time points. (2) The PIP level at each time point showed no significant differences between two groups (with t values from 0. 399 to 1. 167, P values above 0. 05). At PVH 4 and 8, the mean airway .pressure values of dogs in group SI were significantly higher than those in group IP (with t values respectively 1.926 and 1. 190, P values below 0.05). At PVH 4, 6, and 8, the dynamic lung compliance levels of dogs in group SI [(9.5 ± 1.9), (12.8 ± 2. 1), (13. 1 ± 1.8) mL/cmH2O] were significantly lower than those in group IP [(11.6 ± 1.2), (15.4 ± 1.8), (14.9 ± 0.8) mL/cmH2O], with t values respectively 2. 289, 2. 303, 2. 238, P values below 0.05. Compared with those observed immediately after injury, PIP and the mean airway pressure values of dogs in two groups were significantly lowered at each treatment time point (with t values from 2. 271 to 7. 436, P <0. 05 or P < 0.01); the dynamic lung compliance levels were significantly elevated in both groups at PVH 6 and 8 (with t values from 2. 207 to 4. 195, P < 0.05 or P <0.01). (3) Heart rate, MAP, and PAP levels at each time point between two groups showed no significant differences (with t values from 0. 001 to 1. 170, P values above 0. 05). At PVH 4, 6, and 8, CO levels in group IP [(0. 6 + 0. 3), (0. 6 + 0. 4), (0. 5 + 0. 7) L/min] were significantly lower than those in group SI [(1.5 0.7), (1.8 + 1.1), (1.6 +0.9) L/min], with t values respectively 3. 028, 2.511, 2.363, P values below 0.05. Compared with that observed immediately after injury, CO level in group IP was significantly lowered at PVH 4, 6, or 8 (with t values respectively 2. 363, 2. 302, 2. 254, P values below 0. 05).

CONCLUSIONSBoth lung recruitment maneuvers can effectively improve oxygenation and lung compliance of dogs with severe smoke inhalation injury. IP is more effective in improving lung compliance, while SI shows less impact on the hemodynamic parameters.

Animals ; Blood Gas Analysis ; veterinary ; Dogs ; Hemodynamics ; Lung Compliance ; physiology ; Oxygen ; blood ; Oxygen Consumption ; physiology ; Positive-Pressure Respiration ; methods ; Respiration, Artificial ; Respiratory Mechanics ; Severity of Illness Index ; Smoke ; adverse effects ; Smoke Inhalation Injury ; physiopathology ; therapy

This study was conducted to evaluate the effectiveness and safety of a practical protocol for titrating positive end-expiratory pressure (PEEP) involving recruitment maneuver (RM) and decremental PEEP. Seventeen consecutive patients with acute lung injury who underwent PEEP titration were included in the analysis. After baseline ventilation, RM (continuous positive airway pressure, 35 cm H2O for 45 sec) was performed and PEEP was increased to 20 cmH2O or the highest PEEP guaranteeing the minimal tidal volume of 5 mL/kg. Then PEEP was decreased every 20 min in 2 cmH2O decrements. The "optimal" PEEP was defined as the lowest PEEP attainable without causing a significant drop (>10%) in PaO2. The "optimal PEEP" was 14.5 +/- 3.8 cmH2O. PaO2 /FI O2 ratio was 154.8 +/- 63.3 mmHg at baseline and improved to 290.0 +/- 96.4 mmHg at highest PEEP and 302.7 +/- 94.2 mmHg at "optimal PEEP", both significantly higher than baseline (p<0.05). Static compliance was significantly higher at "optimal" PEEP (27.2 +/- 10.4 mL/ cmH2O) compared to highest PEEP (22.3 +/- 7.7 mL/cmH2O) (p<0.05). Three patients experienced transient hypotension and one patient experienced atrial premature contractions. No patient had gross barotrauma. PEEP titration protocol involving RM and PEEP decrement was effective in improving oxygenation and was generally welltolerated.
Adult ; Aged ; Aged, 80 and over ; Blood Pressure ; Female ; Heart Rate ; Human ; Male ; Middle Aged ; Oxygen/blood ; Pneumonia/therapy ; Positive-Pressure Respiration/adverse effects/*methods ; Pulmonary Gas Exchange ; Respiratory Distress Syndrome, Adult/*therapy ; Retrospective Studies