[Abstract] Objective To investigate the value of lung isolation technique in surgical anesthesia for pulmonary contusion combined with rib fracture. Methods Ninety-eight patients with unilateral pulmonary contusion combined with multiple multiple rib fractures treated with internal fixation were randomly divided into two groups, using double-lumen bronchial catheter intubation (group D) and tracheal tube intubation (group E), respectively. Intraoperative changes in SPO2 and Ppeak values were recorded in the two groups. The SPO2 in group D remained stable compared with group E (98.71±1.76% vs. 92.50±8.95%,P<0.01,) and the Ppeak value in group E was higher compared with group D (26.42±1.80cmH2O vs. 20.52±6.54cmH2O,P<0.01). Conclusion When operating on pulmonary contusion combined with multiple rib fractures, the best time for internal fixation of the ribs should be performed after 72 hours of injury; lung isolation with double-lumen bronchial catheter intubation can effectively prevent intraoperative poor ventilation and airway obstruction of the healthy side of the lung. 【Key words】Pulmonary isolation; pulmonary contusion; rib fracturePulmonary contusion is a serious complication after chest trauma, often accompanied by multiple multiple rib fractures. Currently, surgical treatment with a memory alloy circumferential receiver is a better way to manage multiple rib fractures. The choice of intravenous complex anesthesia with single-lumen endotracheal tube has potential risks and safety concerns in airway management. In this study, we used a lung isolation technique with healthy-side double-lumen bronchial intubation to prevent intraoperative poor ventilation of the patient's healthy side lung, which is reported below.
Materials and methods
General data were selected from January 2006 to April 2011 in 98 patients who were treated surgically with memory alloy ring splints for unilateral pulmonary contusion combined with multiple rib fractures, including 58 males and 40 females, ASA grade II-IV, age 17-69 years, weight 42-86 kg. all patients had different degrees of pulmonary contusion and hemopneumothorax, and some patients also had affected side All patients had varying degrees of pulmonary contusion and hemopneumothorax, and some patients also had collapse of the affected chest wall, lung parenchymal trauma and paradoxical breathing. All patients were randomly divided into a double-lumen bronchial tube intubation group (Group D) and a tracheal tube intubation group (Group E). Exclusion criteria: patients with bilateral lung contusion combined with bilateral rib fractures; patients with acute renal insufficiency or untreated acute diabetes mellitus; patients with preoperative SPO2 not reaching 94% with oxygen therapy; and patients with preoperative chronic obstructive pulmonary disease.
After admission, the electrocardiogram, SPO2 and blood pressure were monitored with a Mindray Beneview T8 monitor. Anesthesia was induced by intravenous injection of midazolam 0.05 mg/kg, fentanyl 2ug/kg, vecuronium bromide 0.1 mg/kg, and propofol 1 to 2 mg/kg. patients in group D were inserted with a double-lumen bronchial catheter on the healthy side, and the catheter position was determined by fiberoptic bronchoscopy after intubation and position fixation. group E was intubated with a tracheal tube. All patients were mechanically ventilated intraoperatively with respiratory parameters: VT 8-10 ml/kg, fraction of inspired oxygen (FiO2) 1.0, inspiratory-to-expiratory ratio 1:1-2, RR 12-14 times/min, maintenance PETCO 230-45 mmHg. intravenous pumping of remifentanil 0.1-0.2ug.kg-1.min-1 and propofol 3-5mg.kg-1.h-1 was used to maintain Anesthesia was maintained with intermittent pushing of vecuronium bromide to maintain muscle relaxation.
The intraoperative SPO2 changes and Ppeak values were monitored continuously, and the lowest intraoperative SPO2 value and the highest Ppeak value were recorded for each patient.
Statistical analysis was performed using SPSS13.0 statistical software, and the measurement data were expressed as mean ± standard deviation (±S), and one-way ANOVA was used for comparison between groups, and P < 0.05 was considered a statistically significant difference.
Results
There were no statistically significant differences between the two groups in the general conditions of patients such as gender, age, weight, interval between injury and surgery, and SPO2 before surgery (Table 1).
Table 1 General information of patients in the two groups ± S
Group Number of cases Gender (M/F) Age (y) Weight (kg) Post-injury time (d) Pre-operative SPO2 (%)
Group D 4930/1949.21±15.6763.41±10.956.44±2.0594.27±3.52
Group E 4928/2143.68±14.6460.32±13.616.12±1.9893.25±3.82
P value > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05
All 49 cases in group D completed internal rib fixation, dissection and clot removal in the healthy side position, and their vital signs were stable during the operation, and the SPO2 in group D remained stable compared with group E. The difference was statistically significant (P < 0.01), and the Ppeak value (cmH2O, 1 cmH2O = 0.098 kPa) in group E was higher than that in group D. The difference was statistically significant (P < 0.01) (Table 2). .
Table 2 Changes in intraoperative SPO2 and Ppeak values of patients in both groups ± S
Number of cases SPO2 (%) Ppeak (cmH2O)
Group D 4998.71±1.76a26.42±1.80a
Group E4992.50±8.9520.52±6.54
t-value 6.1566.540
P value P < 0.01P < 0.01
Note: compared with group E, aP < 0.01
Three patients in group E were operated within 72 hours after trauma due to obvious paradoxical breathing, and after induction of anesthesia and placement of the position, the airway resistance increased significantly after 3-5 minutes in the healthy side lying position, with Ppeak > 40 cmH2O (1 mmHg = 0.133 Kpa, 1 mmHg = 1.36 cmH20), until machine-controlled breathing could not be achieved, and SPO2 decreased progressively from 99% to 50% The patient was immediately suctioned, and a large amount of dark red fluid was seen to be aspirated from the trachea, with some blood crust formation. The patient was immediately placed in a lying position, and the SPO2 gradually rebounded after alternating hand-controlled breathing and suctioning. After repeated suctioning, the ventilation gradually improved, the airway resistance decreased, and the SPO was 2100%, so the operation was suspended and transferred to the ICU for treatment. 100-250 ml of secretions were aspirated from each of the three patients, and the operation was successfully completed under double-lumen bronchial intubation again after the condition stabilized. The patient was found to have coagulated hemothorax, pulmonary atelectasis and solid signs on the affected side.
Discussion
Patients with thoracic trauma often have concomitant chest wall contusions, chest wall collapse, and rib fractures. Clinical workup sometimes pays attention to the severity of chest wall trauma only, neglecting the extent of pulmonary parenchymal trauma. Pulmonary contusion can be followed by two pathophysiological changes namely exudation of the lung parenchyma combined with pulmonary atelectasis and exudation of the thoracic cavity, which is the main cause of respiratory failure after trauma. Yu Hongquan [1] divided the changes in the course of the disease into four phases according to the characteristics of the changes in chest CT at different times after lung contusion: acute trauma phase, pulmonary exudation phase, thoracic exudation phase, and absorption improvement phase. It is also pointed out that the pulmonary exudate phase occurs 24-72h after the injury, which is characterized by pain, gradually increasing dyspnea, breath-holding, and decreasing SPO2. At this time, chest CT shows enhanced pulmonary texture, indistinct structure, fusion into patches, and some solid lung changes. This period is the peak stage for the occurrence of post-traumatic ARDS, and the patient’s respiratory and blood oxygen changes need to be closely monitored. After pulmonary solidification, chest exudation is aggravated, and the early or late and the amount of chest exudation usually reflects the severity of pulmonary contusion. Therefore, the best time to perform internal rib fixation should avoid the peak period of pulmonary consolidation and thoracic exudation. If the patient has difficulty in maintaining spontaneous breathing during this period, it is advisable to perform respiratory support therapy with endotracheal intubation while providing adequate analgesia, and do not rush to operate for safety.
In airway management, the lung isolation technique using double-lumen bronchial intubation can better achieve the advantage of complete left and right lung separation [2-4]. Complete functional temporary isolation of both lungs is the most important aspect of emergency chest trauma surgery, and this technique is sometimes a life-saving measure that effectively prevents the escape of blood sputum or secretions from the infected lung to the non-involved lung [5-7]. In the tracheal intubation group, three patients developed progressive ventilation difficulties after placement in the position, to the point that neither machine nor hand-controlled breathing was possible. After eliminating the possibility of airway spasm in the lightly anesthetized state, the possibility of mechanical obstruction was considered, because the only way for it to come so suddenly and completely was mechanical obstruction. Due to the pain in the chest after the patient’s rib fracture, the patient’s cough is restricted, which leads to the accumulation of blood sputum in the lungs, and when the position is changed from supine to prone, the sputum flows into the healthy side of the main ventilating side, or even into the main trachea, leading to an increase in airway pressure and blocking the airway and then causing mechanical obstruction [8,9]. For this reason, a lung isolation technique with double-lumen bronchial intubation is appropriate for airway management to effectively address this problem.
In conclusion, when operating on pulmonary contusions combined with multiple rib fractures, the best time for internal rib fixation is after 72 hours of injury; lung isolation with double-lumen bronchial catheter intubation can effectively prevent intraoperative poor ventilation of the healthy lung and airway obstruction.