Pre-operative pulmonary assessment and risk factors for post-operative pulmonary complications in elective abdominal surgery in Nigeria

Pulmonary function testing in preoperative high-risk patients

BACKGROUND

Postoperative respiratory failure is the most frequent complication in postsurgical patients. The purpose of this study is to assess whether pulmonary function testing in high-risk patients during preoperative assessment detects previously unknown respiratory impairments which may influence patient outcomes.

METHODS

A targeted patient screening by spirometry and the measurement of the diffusing capacity of the lung for carbon monoxide (DLCO) was implemented in the anesthesia department of a tertiary university hospital. Patients of all surgical disciplines who were at least 75 years old or exhibited reduced exercise tolerance with the metabolic equivalent of task less than four (MET < 4) were examined. Clinical characteristics, history of lung diseases, and smoking status were also recorded. The statistical analysis entailed t-tests, one-way ANOVA, and multiple linear regression with backward elimination for group comparisons.

RESULTS

Among 256 included patients, 230 fulfilled the test quality criteria. Eighty-one (35.2%) patients presented obstructive ventilatory disorders, out of which 65 were previously unknown. 38 of the newly diagnosed obstructive disorders were mild, 18 moderate, and 9 severe. One hundred forty-five DLCO measurements revealed 40 (27.6%) previously unknown gas exchange impairments; 21 were mild, 17 moderate, and 2 severe. The pulmonary function parameters of forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and DLCO were significantly lower than the international reference values of a healthy population. Patients with a lower ASA class and no history of smoking exhibited higher FVC, FEV1, and DLCO values. Reduced exercise tolerance with MET < 4 was strongly associated with lower spirometry values.

CONCLUSIONS

Our screening program detected a relevant number of patients with previously unknown obstructive ventilatory disorders and impaired pulmonary gas exchange. This newly discovered sickness is associated with low metabolic equivalents and may influence perioperative outcomes. Whether optimized management of patients with previously unknown impaired lung function leads to a better outcome should be evaluated in multicenter studies.

TRIAL REGISTRATION

German Registry of Clinical Studies (DRKS00029337), registered on: June 22nd, 2022.

Incidence of postoperative pulmonary complications in patients undergoing minimally invasive versus median sternotomy valve surgery: propensity score matching

Objective

Postoperative pulmonary complications (PPCs) are common incidents associated with an increased hospital stay, readmissions into the intensive care unit (ICU), increased costs, and mortality after cardiac surgery. Our study aims to analyze whether minimally invasive valve surgery (MIVS) can reduce the incidence of postoperative pulmonary complications compared to the full median sternotomy (FS) approach.

Methods

We reviewed the records of 1076 patients who underwent isolated mitral or aortic valve surgery (80 MIVS and 996 FS) in our institution between January 2015 and December 2019. Propensity score-matching analysis was used to compare outcomes between the groups and to reduce selection bias.

Results

Propensity score matching revealed no significant difference in hospital mortality between the groups. The incidence of PPCs was significantly less in the MIVS group than in the FS group (19% vs. 69%, respectively; P < 0.0001). The most common PPCs were atelectasis (P = 0.034), pleural effusions (P = 0.042), and pulmonary infection (P = 0.001). Prolonged mechanical ventilation time (> 24 h) (P = 0.016), blood transfusion amount (P = 0.006), length of hospital stay (P < 0.0001), and ICU stay (P < 0.0001) were significantly less in the MIVS group. Cardiopulmonary bypass (CBP), aortic cross-clamping, and operative time intervals were significantly longer in the MIVS group than in the matched FS group (P < 0.001). A multivariable analysis revealed a decreased risk of PPCs in patients undergoing MIVS (odds ratio, 0.25; 95% confidence interval, 0.006–0.180; P < 0.0001).

Conclusion

MIVS for isolated valve surgery reduces the risk of PPCs compared with the FS approach.

Risk Factors of Pulmonary Complications After Minimally Invasive Surgery for Elderly Patients with Vertebral Compression Fractures

PURPOSE

To determine the risk factors for pulmonary complications after minimally invasive surgery in elderly patients with vertebral compression fractures (VCFs).

METHODS

A total of 233 elderly patients (age ≥ 65 years) with VCFs, who underwent percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP) surgery at Hebei General Hospital from January 2011 to December 2016, were retrospectively analyzed. Risk factors and the effects of the model were determined by univariate logistic regression analyses and the receiver operating characteristic (ROC) curve, respectively. A risk assessment scale was established based on the risk factors, as well as physiological and surgical scores for mortality and morbidity. The risk assessment scale prospectively evaluated risk factors of pulmonary complications after minimally invasive surgery for elderly patients with VCFs from January to June 2017.

RESULTS

27 patients were diagnosed with pulmonary complications (27/233, 11.59%). There were statistically significant differences between patients with and without pulmonary complications in terms of age, body mass index (BMI), smoking, cardiovascular diseases and old fractures between patients with and without pulmonary complications (P < 0.05). Logistic regression analysis showed that smoking, cardiovascular diseases and old fractures were risk factors (P < 0.05) and area under the curve was 0.738 (95% confidence intervals (CI): 0.648-0.828). 53 elderly patients with VCFs were assessed, 5 of them occurred pulmonary complications. Areas under the curve of preoperative and total risk assessment values were all 0.925.

CONCLUSION

Significant risk factors of pulmonary complications were BMI, cardiovascular diseases and old fractures for patients aged 65 years or elderly with VCFs after minimally invasive surgery. The risk assessment scale gained high accuracy.

Restrictive Spirometric Pattern and Postoperative Pulmonary Complications Following Non-cardiothoracic Surgery

Despite a substantial population of patients with a restrictive spirometric pattern, few studies have evaluated postoperative pulmonary complications (PPCs) after non-cardiothoracic surgery in these patients. We conducted a retrospective cohort study of 681 adults with a normal or restrictive spirometric pattern who were referred for preoperative evaluation of PPC risk before non-cardiothoracic surgery between March 2014 and January 2015. Overall, 8.7% (59/681) of study participants developed a PPC following non-cardiothoracic surgery. The occurrence of PPCs in patients with a restrictive spirometric pattern was higher than that in those with normal spirometry (12.4% [35/282] vs. 6.0% [24/399], P = 0.003). The occurrence of PPCs increased across the categories of restrictive spirometric pattern severity (6.0% with a normal spirometric pattern vs. 6.5% with a mild restrictive spirometric pattern [60 ≤ forced vital capacity (FVC) < 80% predicted] vs. 21.2% with a moderate-to-severe restrictive spirometric pattern [FVC < 60% predicted], P for trend test < 0.001). The length of hospital stay (P for trend = 0.002) was longer, and all-cause mortality at 30 days (P for trend = 0.008) and 90 days (P for trend = 0.001) was higher across the restrictive spirometric pattern severity. In multivariable-adjusted analyses, a moderate-to-severe restrictive spirometric pattern was associated with a higher risk of PPCs compared with a normal spirometric pattern (adjusted odds ratio 2.64, 95% confidence interval 1.22–5.67). The incidence of PPCs in patients with a restrictive spirometric pattern was higher than that in those with a normal spirometric pattern, especially in patients with a moderate-to-severe restrictive spirometric pattern. Patients with a moderate-to-severe restrictive spirometric pattern should be regarded as high risk for developing PPCs following non-cardiothoracic surgery.