Predicting postoperative pulmonary complications: implications for outcomes and costs

Perioperative risk factors for postoperative pulmonary complications after major oral and maxillofacial surgery with microvascular reconstruction: A retrospective analysis of 648 cases

BACKGROUND

Postoperative pulmonary complications (PPCs) are common and result in prolonged hospital stays, higher costs and increased mortality. However, data on the incidence and predictors of PPCs after major oral and maxillofacial surgery with microvascular reconstruction are rare. This retrospective analysis identifies perioperative risk factors for postoperative pulmonary complications (PPCs) after major oral and maxillofacial surgery with microvascular reconstruction.

METHODS

Perioperative data and patient records of 648 subjects were analyzed in the period of June 2007 to May 2013. PPCs were defined as pneumonia, atelectasis, pleural effusions, pulmonary embolism, pulmonary oedema, pneumothorax or respiratory failure.

RESULTS

18.8% of all patients developed PPCs. Patient-related risk factors for PPCs were male sex, advanced age, smoking, alcohol abuse, a body mass index >30, American Society of Anaesthesiologists grade higher than 2, pre-existent pulmonary diseases and preoperative antihypertensive medication. Among the investigated procedure-related variables, the length of the operation, the amount of fluid administration and blood transfusion and an impaired oxygenation index during surgery were shown to be associated with the development of PPCs. Using a multivariable logistic regression model, we identified a body mass index >30, American Society of Anaesthesiologists grade higher than 2 and alcohol abuse as independent risk factors for PPCs.

CONCLUSIONS

Several perioperative factors can be identified that are associated with the development of PPCs. Patients having one or more of these conditions should be subjected to intensified postoperative pulmonary care.

Tapered-cuff Endotracheal Tube Does Not Prevent Early Postoperative Pneumonia Compared with Spherical-cuff Endotracheal Tube after Major Vascular Surgery

Background

Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure.

Methods

This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency.

Results

Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P < 0.001). Although microaspiration frequencies were high, they did not differ between groups.

Conclusion

For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.

Early Pulmonary Complications following Total Knee Arthroplasty under General Anesthesia: A Prospective Cohort Study Using CT Scan

Purpose. Postoperative pulmonary complications (PPCs) are common after major surgeries. However, the number of studies regarding PPCs following total knee arthroplasty (TKA) is limited. The aim of this study was to determine the incidence of early PPCs following TKA by computed tomography (CT) scan and to identify associated risk factors. Methods. Patients, who were diagnosed with osteoarthritis or rheumatoid arthritis and underwent primary TKA at our institution, were included in this prospective cohort study. Patients received a standard procedure of TKA under general anesthesia. Chest CT scan was performed during 5–7 days postoperatively. Univariate analysis and multivariate logistic regression analysis were employed to identify the risk factors. Results. The total incidence of early PPCs following TKA was 45.9%. Rates of pneumonia, pleural effusion, and atelectasis were 14.4%, 38.7%, and 12.6%, respectively. Lower body mass index and perioperative blood transfusion were independent risk factors for PPCs as a whole and associated with atelectasis. Postoperative acute episode of hypoxemia increased the risk of pneumonia. Blood transfusion alone was related to pleural effusion. Conclusions. The incidence of early PPCs following TKA was high. For patients with relevant risk factors, positive measures should be adopted to prevent PPCs.

Preoperative Evaluation: Estimation of Pulmonary Risk

Postoperative pulmonary complications (PPCs) are common after major non-thoracic surgery and associated with significant morbidity and high cost of care. A number of risk factors are strong predictors of PPCs. The overall goal of the preoperative pulmonary evaluation is to identify these potential, patient and procedure-related risks and optimize the health of the patients before surgery. A thorough clinical examination supported by appropriate laboratory tests will help guide the clinician to provide optimal perioperative care.

Intraoperative protective mechanical ventilation for prevention of postoperative pulmonary complications: a comprehensive review of the role of tidal volume, positive end-expiratory pressure, and lung recruitment maneuvers

Postoperative pulmonary complications are associated with increased morbidity, length of hospital stay, and mortality after major surgery. Intraoperative lung-protective mechanical ventilation has the potential to reduce the incidence of postoperative pulmonary complications. This review discusses the relevant literature on definition and methods to predict the occurrence of postoperative pulmonary complication, the pathophysiology of ventilator-induced lung injury with emphasis on the noninjured lung, and protective ventilation strategies, including the respective roles of tidal volumes, positive end-expiratory pressure, and recruitment maneuvers. The authors propose an algorithm for protective intraoperative mechanical ventilation based on evidence from recent randomized controlled trials.

Intraoperative mechanical ventilation strategies to prevent postoperative pulmonary complications in patients with pulmonary and extrapulmonary comorbidities

A variety of patient characteristics and comorbidities have been identified, which increase the risk of postoperative pulmonary complications (PPCs), including smoking, age, chronic obstructive pulmonary disease, pulmonary hypertension, obstructive sleep apnea, cardiac and neurologic diseases as well as critical illness. In contrast to the variety of conditions, evidence for specific intraoperative ventilation strategies to reduce PPC is very limited for most comorbidities. Here, we provide an overview of and discuss possible implications for the intraoperative ventilatory management of patients with comorbidities.

Development and implementation of a dedicated postoperative evaluation service to improve compliance of postoperative visits

Background and Aims:

Postoperative patient evaluation is an integral component of perioperative care. An audit of our anesthesia department's records demonstrated a compliance rate of <50%. We postulated that the development of clinical anesthesia service dedicated to performing such evaluations would improve compliance significantly.

Materials and Methods:

This retrospective study examined postoperative follow-up completion rate at a large academic center. Data were collected from 58,000 anesthetics during three periods, between each of which an intervention was introduced. The first period examined completion rate when postoperative evaluations were left to the team performing the anesthetic. During the second period, this task was delegated to groups of anesthesiologists based on surgical subspecialty; these smaller groups utilized rotating residents. The third period examined completion rate after implementation of a postoperative evaluation service. All periods utilized the department's electronics database to identify operative patients. The number of adverse anesthesia events reported was also recorded.

Results:

A significant difference in the proportions of compliance with postoperative evaluations among all three periods was detected. Compliance was 47% during period one and improved to 66% during period two. During period three, which employed a postoperative evaluation service, compliance was 83%. The number of adverse events reported per month increased significantly following the first study period from 95 reported monthly events to 215 and 201 in the second and third periods, respectively.

Conclusion:

By creating a dedicated postoperative evaluation service using available technology, we improved postoperative evaluation completion rate from 47% to 83%, and demonstrated a significant increase in the number of adverse events reported. Based on this, we support the deployment of a dedicated service as a quality improvement initiative.

Pulmonary complications after major abdominal surgery: National Surgical Quality Improvement Program analysis

BACKGROUND

Postoperative pulmonary complications (PPCs) after major abdominal surgery are common and associated with significant morbidity and high cost of care. The objective of this study was to identify the risk factors for PPCs after major abdominal surgery.

MATERIALS AND METHODS

The American College of Surgeons' National Surgical Quality Improvement Program database from 2005-2012 was queried for patients who underwent major abdominal surgery (esophagectomy, gastrectomy, pacnreatectomy, enterectomy, hepatectomy, colectomy, and proctectomy). Predictors of PPCs were identified using multivariate logistic regression.

RESULTS

Of 165,196 patients who underwent major abdominal surgery 9595 (5.8%) suffered PPCs (pneumonia 3.2%, prolonged ventilator support ≥48 h 3.0%, and unplanned intubation 2.8%). On multivariate analysis, significant predictors of overall and individual PPCs include esophagectomy, advanced American Society of Anesthesiology Classification System, dependent functional status, prolonged operative time, age ≥80 y, severe chronic obstructive pulmonary disease, preoperative shock, ascites, and smoking. Obesity was not a risk factor. Female gender was overall protective for PPCs.

CONCLUSIONS

PPCs after abdominal procedures are associated with a number of clinical variables. Esophageal operations and American Society of Anesthesiology Classification System were the strongest predictors. These results provide a framework for identifying patients at risk for developing pulmonary complications after major abdominal surgery.