Perioperative Respiratory Function Research Articles

Usefulness of sternal closure with bioresorbable plate in respiratory function after coronary artery bypass grafting

ObjectiveThe aim of our study is to investigate that sternal reconstruction using bioresorbable plate in median sternotomy may reduce postoperative respiratory dysfunction when compared with wire cerclage only.MethodsWe reviewed 107 patients who were undergone coronary artery bypass grafting with median sternotomy. Patients were divided into two groups; patients underwent sternal reconstruction with bioresorbable plate and wire cerclage (S group, n = 56), patients with wire cerclage only (N group, n = 51), and perioperative respiratory function and postoperative pain score data were analyzed and compared between two groups.ResultsThere was no significantly difference in preoperative respiratory function in both groups. However, in postoperative change rate of respiratory function, N group had significant decrease compared with S group in vital capacity (VC) (N: S = 74.8 ± 12.4: 85.2 ± 14.8%, p = 0.020), VC as a percentage of predicated VC (N: S = 75.0 ± 12.5: 86.4 ± 15.1%, p = 0.012), and forced expiratory volume in the first second (N: S = 73.7 ± 9.2: 85.3 ± 16.4%, p = 0.012). In Prince Henry Pain Scale, there were significantly more in N group compared with S group (N: S = 3.4 ± 1.0: 2.6 ± 1.4, p = 0.003).ConclusionSternal fixation with bioresorbable plate could reduce impairment of postoperative respiratory function in comparison to wire cerclage only.

Dual effects of leptin in perioperative gas exchange of morbidly obese patients.

Leptin has shown positive effects on respiratory function in experimental settings. The role of leptin on perioperative respiratory function in morbidly obese patients has not been established. We performed a retrospective analysis of morbidly obese patients undergoing laparoscopic sleeve gastrectomy. Fasting serum leptin and interleukin (IL)-6 were measured preoperatively, and arterial blood gases were obtained pre- and postoperatively. Outcome variables were arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), and differences in PaO2 and PaCO2 between pre- and postoperative values (ΔPaO2, ΔPaCO2; postoperative minus preoperative). Patients with lower (<40 μg/L) and higher (≥40 μg/L) leptin levels were compared. Bravais-Pearson’s correlation, multiple linear regression, and logistic regression analysis were performed. A total of 112 morbidly obese patients were included. Serum leptin was significantly higher in females than in males (42.86±12.89 vs. 30.67±13.39 μg/L, p<0.0001). Leptin was positively correlated with body mass index (r = 0.238; p = 0.011), IL-6 (r = 0.473; p<0.0001), and ΔPaO2 (r = 0.312; p = 0.0008). Leptin was negatively correlated with preoperative PaO2 (r = -0.199; p = 0.035). Preoperative PaO2 was lower, ΔPaCO2 was smaller, and ΔPaO2 was greater in the high leptin group than in the low leptin group. In multiple regression analysis, leptin was negatively associated with preoperative PaO2 (estimate coefficient = -0.147; p = 0.023). In logistic regression analysis, leptin was associated with improved ΔPaO2 (odds ratio [OR] = 1.104; p = 0.0138) and ΔPaCO2 (OR = 0.968; p = 0.0334). Leptin appears to have dual effects related to perioperative gas exchange in obese patients undergoing bariatric surgery. It is associated with worse preoperative oxygenation but improved respiratory function after surgery.

The Effect of introducing a nurse guided enhanced recovery after surgery program on patients undergoing hepatectomy

Background: enhanced recovery after surgery (ERAS) could shorten hospital stay and decrease postoperative complications for patients undergoing colorectal surgery. Whether ERAS have the same effect in patients undergoing hepatectomy is not clear, researches led by nurse are especially rare. The study aimed at investigating the safety, feasibility and efficiency of nurse guided ERAS program on patients undergoing hepatectomy Method: patients undergoing liver resection treated with nurse guided ERAS program were taken for ERAS group. ERAS program included: perioperative respiratory function training, perioperative diet guidance, early postoperative activity and postoperative pain management. Primary outcome measures we postoperative length of stay and postoperative complications. Secondary outcome measures were the first time to flatus and defecation, NRS on first and second postoperative day (POD), mortality and readmission rate. Result: The study included totally 100 patients, the patients in each group were 50.The length of stay of patients in ERAS group was shorter than control group (5 days vs 7 days, P=0.001). The overall complications rate and general complications rate of patients in ERAS group were obviously lower than control group (12% vs 30%, P=0.027; 8% vs 24%, P=0.029). The first time to flatus and defecation of ERAS group were both earlier than control group (3 days vs 4 days, P=0.000; 5 days vs 6 days, P=0.010). The NRS score on POD 1 and POD 2 of the ERAS groups were both lower than control group (6 vs 4, P=0.006; 5 vs 3, P=0.000). The surgery-related complications rate of two groups had no significant difference. There were no perioperative mortality or readmission of two groups in the study (0, P=1.000). Conclusion: The application of nurse guided ERAS program safe, effective and feasible for patients undergoing liver resection. It shortened postoperative length of stay and decreased postoperative complication. At the same time, it reduced postoperative pain and improved patient comfort.

The influence factors of lung compliance during perioperative period

Background Good lung compliance is a necessary condition to maintain perioperative respiratory function. Along with scientific research and clinical trials on the lung compliance, the influence of many factors on lung compliance in perioperative period are attracting more and more people's attention. Objective To summarize the related literature about the influence factors of lung compliance during perioperative period. Content This paper demonstrates the influence factors of lung compliance during perioperative period from several aspects, such as anesthesia methods, anesthetics, ventilator settings, body position, special type of surgery and patients' factors. Trend Lung compliance is an important index of pulmonary function and study on the influences of lung compliance during anesthesia are great significant to assessment of lung protection during operation and postoperative reduction of respiratory system injury preoperative patients. Key words: Perioperative period; Pulmonary compliance; Influence factors

Non-invasive ventilation in the perioperative period

### Key points Maintenance of adequate perioperative respiratory function is of paramount importance for the safe delivery of anaesthesia and surgery and an uneventful recovery thereafter. Optimized tissue oxygenation plays a pivotal role in the preservation of organ function and is vital for wound healing and the protection of surgical anastomoses. ### Physiological changes in the perioperative period Surgical patients often experience profound physiological changes to their respiratory system. General anaesthesia reduces oropharyngeal tone and airway reflexes. A decrease in respiratory rate and tidal volumes from opioid and anaesthetic agents leads to reduced minute ventilation, hypercarbia, and displacement of alveolar oxygen. This may be compounded by a blunted central ventilatory drive. Furthermore, functional residual capacity (FRC) declines, reducing the effective oxygen reservoir. Closing capacity approaches FRC during general anaesthesia, causing small airway closure and atelectasis and ventilation–perfusion mismatch is exacerbated, leading to increased physiological deadspace and shunt. There is also increasing recognition of ventilator-induced lung injury as a contributory factor to postoperative pulmonary dysfunction. Patient factors such as advanced age, premorbid cardiorespiratory disease, smoking, obesity, and anaemia may all increase the likelihood of developing postoperative pulmonary complications (PPC). Surgical factors include positional changes, diaphragmatic splinting, and direct surgical injury to the lungs, pleura, diaphragm, chest wall, abdominal wall, or to the nerves supplying the respiratory …

Anesthetic considerations in 65 patients undergoing unilateral pneumonectomy: problems related to fluid therapy and hemodynamic control

Study Objective To examine perioperative management and complications in patients undergoing pneumonectomy. Design Observational cohort study. Setting University-affiliated city hospital. Measurements 65 patients who underwent unilateral pneumonectomy for resection of lung cancer between March 1997 and October 2007 were included in this study. Patients who underwent pneumonectomy were then classified into two groups: Group C patients had signs of postoperative acute right heart failure, and Group N patients had no signs of postoperative acute right heart failure. Main Results In the pneumonectomy patients, extubation did not occur in 8 patients (12%) and postoperative death occurred in 4 patients (6%), compared with no such occurrences among patients who underwent lobectomy. Perioperative respiratory function was significantly lower in Group C ( P < 0.05) than Group N. Fluid infusion volume, fluid balance volume, intraoperative total fluid balance, urine output volume, blood loss volume, blood transfusion volume, times of administration of vasopressors intraoperatively, and number of patients requiring intraoperative administration of catecholamines were significantly greater in Group C ( P < 0.05) than Group N. Conclusions Fluid infusion volume, fluid balance volume, intraoperative total balance, blood loss volume, and blood transfusion volume were important intraoperative risk factors in the development of postoperative right-sided heart failure.

Impact of spinal anaesthesia on peri‐operative lung volumes in obese and morbidly obese female patients*

Although obesity predisposes to postoperative pulmonary complications, data on the relationship between body mass index (BMI) and peri-operative respiratory performance are limited. We prospectively studied the impact of spinal anaesthesia, obesity and vaginal surgery on lung volumes measured by spirometry in 28 patients with BMI 30-40 kg.m(-2) and in 13 patients with BMI > or = 40 kg.m(-2). Vital capacity, forced vital capacity, forced expiratory volume in 1 s, mid-expiratory and peak expiratory flows were measured during the pre-operative visit (baseline), after effective spinal anaesthesia with premedication, and after the operation at 20 min, 1 h, 2 h, and 3 h (after mobilisation). Spinal anaesthesia and premedication were associated with a significant decrease in spirometric parameters. Spinal anaesthesia and premedication were associated with a significant decrease in spirometric parameters; mean (SD) vital capacities were - 19% (6.4) in patients with BMI 30-40 kg.m(-2) and - 33% (9.0) in patients with BMI > 40 kg.m(-2). The decrease of lung volumes remained constant for 2 h, whereas 3 h after the operation and after mobilisation, spirometric parameters significantly improved in all patients. This study showed that both spinal anaesthesia and obesity significantly impaired peri-operative respiratory function.

Pulmonary function after cardiac and thoracic surgery.

Perioperative care is undergoing significant change due to clinical advances and economic pressures. As more emphasis is placed on costcontainment and improved efficiency, current practices should be reviewed and critiqued to determine whether they are actually effective. Common problems, such as postoperative pulmonary complications, should be a focus of these efforts because the “bottom line” is to devise methods to reduce these complications and so decrease the costs of medical care. This requires a multifaceted approach that entails a better understanding of the causes of the complications, devising effective treatments and preventive strategies, and performing outcome studies to determine the success of currently used and new procedures. In this review, I examine the pulmonary changes after surgery involving the thoracic cavity and the consequences of modern pain management techniques. Perioperative Respiratory Function: A

Post-operative respiratory complications

Induction of anaesthesia, the presence of pre-operative respiratory disease, the occurrence of physiologically intrusive intra-operative events, and the development of post-operative respiratory complications may, individually or in combination, compromise peri-operative respiratory function. The respiratory system is more prone to complications in the post-operative period than other organ systems. Even patients with previously normal lung function experience clinically important post-operative complications after abdominal surgery with an incidence of 6-10%. A much larger proportion of patients develop less severe complications, such as atelectasis, excessive cough and slight fever, which frequently are not recognised. These less severe complications occur in 25-75% of patients after upper abdominal surgery. 1 Pulmonary complications occur most commonly in the elderly or high risk patient, in whom they account for substantial post-operative mortality and morbidity. Early post-operative complications develop particularly in the obese, the elder!y, smokers and those with cardiorespiratory diseases. Late postoperative pulmonary complications are usually the result of progressive pulmonary mechanical factors (intrapulmonary shunt, ventilation/perfusion mismatch). Depression of respiratory function in the immediate post-operative period can be the result of administration of opioid or anaesthetic drugs, hypoventilation (lack of respiratory drive) and residual muscle paralysis. These may lead to oxygen desatur-

Lateral Thoracotomy and One-Lung Anesthesia in Patients with Morbid Obesity

Between May, 1980, and October, 1981, 22 morbidly obese patients ranging in weight from 93.4 to 236.8 kg (average, 145.2 kg) underwent transthoracic gastric stapling. Fourteen of these operations were performed using endobronchial intubation and selective collapse of the left lung to facilitate surgical exposure. The patients were compared with 22 consecutive patients treated by transabdominal gastric stapling during the same period. None of the 44 patients had evidence of chronic alveolar hypoventilation (pickwickian syndrome). In terms of operating time, blood loss, duration of intubation, and hospital stay, the two groups did not differ significantly. Despite marked shunting during one-lung ventilation, satisfactory arterial oxygen tension (PaO 2) could be demonstrated on 100% oxygen for all thoracotomy patients (PaO 2 range, 67 to 230 torr; mean, 132.3 torr). In fact, except for a lower PaO 2 during one-lung anesthesia, the thoracotomy patients were indistinguishable from the laparotomy patients in terms of perioperative respiratory function. Pain, sedation, and positioning led to significant decreases in vital capacity and one-second forced expiratory volume in both groups on the first postoperative day, and in the thoracotomy group on the second day. There were only two wound infections in the thoracotomy group, as opposed to six infections with two dehiscences in the laparotomy group. It is concluded that lateral thoracotomy with or without one-lung anesthesia can be performed safely in massively obese patients—at least in those without preexisting alveolar hypoventilation syndrome.