Effects of Intra-operative Cardiopulmonary Variability On Post-operative Pulmonary Complications in Major Non-cardiac Surgery: A Retrospective Cohort Study.

Intraoperative cardiopulmonary variables are well-known predictors of postoperative pulmonary complications (PPC), traditionally quantified by median values over the duration of surgery. However, it is unknown whether cardiopulmonary instability, or wider intra-operative variability of the same metrics, is distinctly associated with PPC risk and severity. We leveraged a retrospective cohort of adults (n = 1202) undergoing major non-cardiothoracic surgery. We used multivariable logistic regression to evaluate the association of two outcomes (1)moderate-or-severe PPC and (2)any PPC with two sets of exposure variables- (a)variability of cardiopulmonary metrics (inter-quartile range, IQR) and (b)median intraoperative cardiopulmonary metrics. We compared predictive ability (receiver operating curve analysis, ROC) and parsimony (information criteria) of three models evaluating different aspects of the intra-operative cardiopulmonary metrics: Median-based: Median cardiopulmonary metrics alone, Variability-based: IQR of cardiopulmonary metrics alone, and Combined: Medians and IQR. Models controlled for peri-operative/surgical factors, demographics, and comorbidities. PPC occurred in 400(33%) of patients, and 91(8%) experienced moderate-or-severe PPC. Variability in multiple intra-operative cardiopulmonary metrics was independently associated with risk of moderate-or-severe, but not any, PPC. For moderate-or-severe PPC, the best-fit predictive model was the Variability-based model by both information criteria and ROC analysis (area under the curve, AUCVariability-based = 0.74 vs AUCMedian-based = 0.65, p = 0.0015; AUCVariability-based = 0.74 vs AUCCombined = 0.68, p = 0.012). For any PPC, the Median-based model yielded the best fit by information criteria. Predictive accuracy was marginally but not significantly higher for the Combined model (AUCCombined = 0.661) than for the Median-based (AUCMedian-based = 0.657, p = 0.60) or Variability-based (AUCVariability-based = 0.649, p = 0.29) models. Variability of cardiopulmonary metrics, distinct from median intra-operative values, is an important predictor of moderate-or-severe PPC.

Postoperative pulmonary complications with adjuvant regional anesthesia versus general anesthesia alone: a sub-analysis of the Perioperative Research Network study.

BACKGROUND: Adjuvant regional anesthesia is often selected for patients or procedures with high risk of pulmonary complications after general anesthesia. The benefit of adjuvant regional anesthesia to reduce postoperative pulmonary complications remains uncertain. In a prospective observational multicenter study, patients scheduled for non-cardiothoracic surgery with at least one postoperative pulmonary complication surprisingly received adjuvant regional anesthesia more frequently than those with no complications. We hypothesized that, after adjusting for surgical and patient complexity variables, the incidence of postoperative pulmonary complications would not be associated with adjuvant regional anesthesia. METHODS: We performed a secondary analysis of a prospective observational multicenter study including 1202 American Society of Anesthesiologists physical status 3 patients undergoing non-cardiothoracic surgery. Patients were classified as receiving either adjuvant regional anesthesia or general anesthesia alone. Predefined pulmonary complications within the first seven postoperative days were prospectively identified. Groups were compared using bivariable and multivariable hierarchical logistic regression analyses for the outcome of at least one postoperative pulmonary complication. RESULTS: Adjuvant regional anesthesia was performed in 266 (22.1%) patients and not performed in 936 (77.9%). The incidence of postoperative pulmonary complications was greater in patients receiving adjuvant regional anesthesia (42.1%) than in patients without it (30.9%) (site adjusted p = 0.007), but this association was not confirmed after adjusting for covariates (adjusted OR 1.37; 95% CI, 0.83-2.25; p = 0.165). CONCLUSION: After adjusting for surgical and patient complexity, adjuvant regional anesthesia versus general anesthesia alone was not associated with a greater incidence of postoperative pulmonary complications in this multicenter cohort of non-cardiothoracic surgery patients.

Evaluation of distal radial artery cross-sectional internal diameter in pediatric patients using ultrasound.

In this study, we measure the radial artery internal diameter (RAID) in children up to 4 years of age before and after the induction of anesthesia. A B-mode portable color Doppler ultrasound was used to measure the RAID. Three sets of measurements were taken for each child before and after the induction of anesthesia and with the wrist in the neutral and dorsiflexed positions. The reliability of the mean value of the RAID in the three sets in 24 patients was established. There were discrepancies between the RAID and the proposed catheter size in some individuals, which may not only render placement difficult but also have potential for arterial injury. There are good reasons to measure the RAID in small children prior to insertion of an intra-arterial catheter.

Factors which predict safe extubation in the operating room following cardiac surgery.

BACKGROUND: Extubation in the operating room (OR) after cardiac surgery is hampered by safety concerns, psychological reluctance, and uncertain economic benefit. We have studied the factors affecting the feasibility of extubation in the OR after cardiac surgery and its safety. METHODS: The outcomes of 78 patients extubated in the OR after open heart surgery were retrospectively compared to a matched control group of 80 patients with similar demographics, co-morbidities, and operative procedures, that were performed over the same time period, but extubated in the intensive care unit (ICU) following a standard weaning protocol. Variables collected included the incidence of subsequent unplanned tracheal reintubation in the ICU, postoperative complications, need for mediastinal re-exploration, surgical and OR times, and ICU and hospital lengths of stay. RESULTS: Out of a total of 372 cardiac procedures performed during the designated time frame, 78 (21%) resulted in extubation in the OR, mostly after off-pump coronary revascularization (41%) and aortic valve replacement (19.4%). Preoperative hypertension, EF ≥30%, off-bypass revascularization and shorter surgical times increased the likelihood of extubation in the OR. Extubation in the OR did not increase perioperative morbidity and mortality rates, but decreased the length of ICU and hospital stays. The incidence of unanticipated subsequent tracheal intubation in the ICU was comparable to noncardiac high-risk procedures (2.5%). CONCLUSIONS: Extubation in the OR can be safely performed in a select group of cardiac surgery patients without any increase in postoperative morbidity or mortality. The proposed mathematical model performed reasonably well in predicting a successful extubation in the OR.

Postoperative Pulmonary Complications, Early Mortality, and Hospital Stay Following Noncardiothoracic Surgery: A Multicenter Study by the Perioperative Research Network Investigators.

Importance: Postoperative pulmonary complications (PPCs), a leading cause of poor surgical outcomes, are heterogeneous in their pathophysiology, severity, and reporting accuracy. Objective: To prospectively study clinical and radiological PPCs and respiratory insufficiency therapies in a high-risk surgical population. Design, Setting, and Participants: We performed a multicenter prospective observational study in 7 US academic institutions. American Society of Anesthesiologists physical status 3 patients who presented for noncardiothoracic surgery requiring 2 hours or more of general anesthesia with mechanical ventilation from May to November 2014 were included in the study. We hypothesized that PPCs, even mild, would be associated with early postoperative mortality and use of hospital resources. We analyzed their association with modifiable perioperative variables. Exposure: Noncardiothoracic surgery. Main Outcomes and Measures: Predefined PPCs occurring within the first 7 postoperative days were prospectively identified. We used bivariable and logistic regression analyses to study the association of PPCs with ventilatory and other perioperative variables. Results: This study included 1202 patients who underwent predominantly abdominal, orthopedic, and neurological procedures. The mean (SD) age of patients was 62.1 (13.8) years, and 636 (52.9%) were men. At least 1 PPC occurred in 401 patients (33.4%), mainly the need for prolonged oxygen therapy by nasal cannula (n = 235; 19.6%) and atelectasis (n = 206; 17.1%). Patients with 1 or more PPCs, even mild, had significantly increased early postoperative mortality, intensive care unit (ICU) admission, and ICU/hospital length of stay. Significant PPC risk factors included nonmodifiable (emergency [yes vs no]: odds ratio [OR], 4.47, 95% CI, 1.59-12.56; surgical site [abdominal/pelvic vs nonabdominal/pelvic]: OR, 2.54, 95% CI, 1.67-3.89; and age [in years]: OR, 1.03, 95% CI, 1.02-1.05) and potentially modifiable (colloid administration [yes vs no]: OR, 1.75, 95% CI, 1.03-2.97; preoperative oxygenation: OR, 0.86, 95% CI, 0.80-0.93; blood loss [in milliliters]: OR, 1.17, 95% CI, 1.05-1.30; anesthesia duration [in minutes]: OR, 1.14, 95% CI, 1.05-1.24; and tidal volume [in milliliters per kilogram of predicted body weight]: OR, 1.12, 95% CI, 1.01-1.24) factors. Conclusions and Relevance: Postoperative pulmonary complications are common in patients with American Society of Anesthesiologists physical status 3, despite current protective ventilation practices. Even mild PPCs are associated with increased early postoperative mortality, ICU admission, and length of stay (ICU and hospital). Mild frequent PPCs (eg, atelectasis and prolonged oxygen therapy need) deserve increased attention and intervention for improving perioperative outcomes.

Concomitant elective resection of pheochromocytoma and repair of aortic abdominal aneurysm.

Perioperative management of a patient with ischemic heart disease with coexisting abdominal aortic aneurysm and pheochromocytoma creates a difficult management dilemma, and surgical intervention in these patients carries a significant risk. The state of catecholamine excess and various other coexisting factors can lead to simultaneous occurrence of abdominal aortic aneurysm and pheocromocytoma. The purpose of this report is to present an integrated approach to the management of concomitant abdominal aortic aneurysm and pheochromocytoma, where a combined surgical approach in addressing these two lesions was preferable due to patient comorbidities and surgical implications without significant complication.

Intraabdominal compartment syndrome complicating transurethral resection of bladder tumor.

Abdominal compartment syndrome can result from many different causes. We present a case where this dangerous syndrome occurred in the operating room during a transurethral resection of a bladder tumor. It was initially recognized by an elevation in the peak inspiratory pressure. We report the typical physiologic changes that occur with this syndrome and its treatment options.

An unusual case of tracheoesophageal fistulae.

Acquired tracheoesophageal fistulae (TEF) are commonly due to malignancy (M. F. Reed and D. J. Mathisen, 2003). We present the case of a patient with a deceptive history for TEF and report an approach that provides adequate oxygenation, ventilation, surgical exposure, and postoperative analgesia with excellent outcome.

A silent patent ductus arteriosus: a culprit or an innocent bystander?

A 4-mm patent ductus arteriosus (PDA) was serendipitously diagnosed during intraoperative transesophageal echocardiography for a noncardiac procedure in an obese adult patient with a history of decreased exercise tolerance and dyspnea, despite a negative preoperative transthoracic examination. This uncommon event poses questions regarding the relevance of this finding to the differential diagnosis of dyspnea in an obese adult with a negative transthoracic echocardiography study, given the unknown prevalence of this pathology and the absence of consensus regarding the clinical management.