Major inpatient surgeries and in-hospital mortality in New South Wales public hospitals in Australia: A state-wide retrospective cohort study

Prediction of complications associated with general surgery using a Bayesian network

BACKGROUND

Numerous attempts have been made to identify risk factors for surgery complications, but few studies have identified accurate methods of predicting complex outcomes involving multiple complications.

METHODS

We performed a prospective cohort study of general surgical inpatients who attended 4 regionally representative hospitals in China from January to June 2015 and January to June 2016. The risk factors were identified using logistic regression. A Bayesian network model, consisting of directed arcs and nodes, was used to analyze the relationships between risk factors and complications. Probability ratios for complications for a given node state relative to the baseline probability were calculated to quantify the potential effects of risk factors on complications or of complications on other complications.

RESULTS

We recruited 19,223 participants and identified 21 nodes, representing 9 risk factors and 12 complications, and 55 direct relationships between these. Respiratory failure was at the center of the network, directly affected by 5 risk factors, and directly affected 7 complications. Cardiopulmonary resuscitation and sepsis or septic shock also directly affected death. The area under the receiver operating characteristic curve for the ability of the network to predict complications was >0.7. Notably, the probability of other severe complications or death significantly increased when a severe complication occurred. Most importantly, there was a 141-fold higher risk of death when cardiopulmonary resuscitation was required.

CONCLUSION

We have created a Bayesian network that displays how risk factors affect complications and their interrelationships and permits the accurate prediction of complications and the creation of appropriate preventive guidelines.

The Gender Gap in Aortic Dissection: A Prospective Analysis of Risk and Outcomes

Aortic dissection (AD) is a severe cardiovascular condition that could have negative consequences. Our study employed a prospective design and examined preoperative, perioperative, and postoperative data to evaluate the effects of gender on various medical conditions. We looked at how gender affected the results of aortic dissection (AD). In contrast to female patients who had more systemic hypertension (p=0.031), male patients had higher rates of hemopericardium (p=0.003), pulmonary hypertension (p=0.039), and hemopericardium (p=0.003). Dobutamine administration during surgery significantly raised the mortality risk (p=0.015). There were noticeably more women patients (p=0.01) in the 71 to 80 age group. Significant differences in age (p=0.004), eGFR at admission (p=0.009), and eGFR at discharge (p=0.006) were seen, however, there was no association between gender and mortality. In conclusion, our findings highlight that gender may no longer be such an important aspect of aortic dissection disease as we previously thought, and this information could have an important contribution for surgeons as well as for anesthesiologists involved in the management of acute aortic dissection.

Is There a High Risk for GI Bleeding Complications in Patients Undergoing Abdominal Surgery?

INTRODUCTION

Gastrointestinal bleeding (GIB) can cause life-threatening situations. Here, endoscopy is the first-line diagnostic and therapeutic mode in patients with GIB among further therapeutic approaches such as embolization or medical treatment. Although GIB is considered the most common indication for emergency endoscopy in clinical practice, data on GIB in abdominal surgical patients are still scarce.

PATIENTS AND METHODS

For the present study, all emergency endoscopies performed on hospitalized abdominal surgical patients over a 2-year period (1 July 2017-30 June2019) were retrospectively analyzed. Primary endpoint was 30-day mortality. Secondary endpoints were length of hospital stay, cause of bleeding, and therapeutic success of endoscopic intervention.

RESULTS

During the study period, bleeding events with an indication for emergency endoscopy occurred in 2.0% (129/6455) of all surgical inhouse patients, of whom 83.7% (n = 108) underwent a surgical procedure. In relation to the total number of respective surgical procedures during the study period, the bleeding incidence was 8.9% after hepatobiliary surgery, 7.7% after resections in the upper gastrointestinal tract, and 1.1% after colonic resections. Signs of active or past bleeding in the anastomosis area were detected in ten patients (6.9%). The overall 30-day mortality was 7.75%.

CONCLUSIONS

The incidence of relevant gastrointestinal bleeding events in visceral surgical inpatients was overall rare. However, our data call for critical peri-operative vigilance for bleeding events and underscore the importance of interdisciplinary emergency algorithms.

Major surgery leads to a proinflammatory phenotype: Differential gene expression following a laparotomy

BACKGROUND

The trauma of surgery is a neglected area of research. Our aim was to examine the differential expression of genes of stress, metabolism and inflammation in the major organs of a rat following a laparotomy.

MATERIALS AND METHODS

Anaesthetised Sprague-Dawley rats were randomised into baseline, 6-hr and 3-day groups (n = 6 each), catheterised and laparotomy performed. Animals were sacrificed at each timepoint and tissues collected for gene and protein analysis. Blood stress hormones, cytokines, endothelial injury markers and coagulation were measured.

RESULTS

Stress hormone corticosterone significantly increased and was accompanied by significant increases in inflammatory cytokines, endothelial markers, increased neutrophils (6-hr), higher lactate (3-days), and coagulopathy. In brain, there were significant increases in M1 muscarinic (31-fold) and α-1A-adrenergic (39-fold) receptor expression. Cortical expression of metabolic genes increased ∼3-fold, and IL-1β by 6-fold at 3-days. Cardiac β-1-adrenergic receptor expression increased up to 8.4-fold, and M2 and M1 muscarinic receptors by 2 to 4-fold (6-hr). At 3-days, cardiac mitochondrial gene expression (Tfam, Mtco3) and inflammation (IL-1α, IL-4, IL-6, MIP-1α, MCP-1) were significantly elevated. Haemodynamics remained stable. In liver, there was a dramatic suppression of adrenergic and muscarinic receptor expression (up to 90%) and increased inflammation. Gut also underwent autonomic suppression with 140-fold increase in IL-1β expression (3-days).

CONCLUSIONS

A single laparotomy led to a surgical-induced proinflammatory phenotype involving neuroendocrine stress, cortical excitability, immune activation, metabolic changes and coagulopathy. The pervasive nature of systemic and tissue inflammation was noteworthy. There is an urgent need for new therapies to prevent hyper-inflammation and restore homeostasis following major surgery.

Postoperative Delirium Following Joint Replacement in Patients With Dementia in New South Wales, Australia: A State-Wide Retrospective Cohort Study

The objective of the current study was to investigate the variation in postoperative delirium in patients with dementia undergoing joint replacement in New South Wales (NSW) Australia public hospitals, identify factors related to its occurrence, and explore the volume-outcome relationship. The NSW Admitted Patient Data (July 2001 to June 2014) were used in this study and included patients with dementia undergoing joint replacement who were 65 or older with minor to severe comorbidities. Mixed-effect logistic models were applied to investigate hospital-level variation and factors associated with postoperative delirium. The between-hospital variability of postoperative delirium was 0.19% prior to 2008-2009 and 8.32% after 2008-2009. Hospital volume was not inversely associated with postoperative delirium rate. During 2001-2014, the incidence of postoperative delirium increased by 13% per annum (95% confidence interval [CI] 10% to 16%), while it increased by 15% per annum (95% CI 8% to 22%) after 2008-2009. An integrated approach addressing complex needs of patients with dementia may reduce the observed unwarranted variation and improve surgical outcomes. [Research in Gerontological Nursing, 13(5), 243-253.].