Intrathecal Morphine for Cardiac Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

ABSTRACT: Cardiac surgeries often result in significant postoperative pain, leading to considerable use of opioids for pain management. However, excessive opioid use can lead to undesirable side effects and chronic opioid use. This systematic review and meta-analysis aimed to evaluate whether preoperative intrathecal morphine could reduce postoperative opioid consumption in patients undergoing cardiac surgery requiring sternotomy. We conducted a systematic search of Cochrane, EMBASE, and MEDLINE databases from inception to May 2022 for randomized controlled trials that evaluated the use of intrathecal morphine in patients undergoing cardiac surgery. Studies that evaluated intrathecal administration of other opioids or combinations of medications were excluded. The primary outcome was postoperative morphine consumption at 24 h. Secondary outcomes included time to extubation and hospital length of stay. The final analysis included ten randomized controlled trials, with a total of 402 patients. The results showed that postoperative morphine consumption at 24 h was significantly lower in the intervention group (standardized mean difference -1.43 [-2.12, -0.74], 95% CI, P < 0.0001). There were no significant differences in time to extubation and hospital length of stay. Our meta-analysis concluded that preoperative intrathecal morphine is associated with lower postoperative morphine consumption at 24 h following cardiac surgeries, without prolonging the time to extubation. The use of preoperative intrathecal morphine can be considered part of a multimodal analgesic and opioid-sparing strategy in patients undergoing cardiac surgery.

The Role of Recipient Thyroid Hormone Supplementation in Primary Graft Dysfunction After Heart Transplantation: A Propensity-Adjusted Analysis.

OBJECTIVES: To investigate whether recipient administration of thyroid hormone (liothyronine [T3]) is associated with reduced rates of primary graft dysfunction (PGD) after orthotopic heart transplantation. DESIGN: Retrospective cohort study. SETTING: Single-center, university hospital. PARTICIPANTS: Adult patients undergoing orthotopic heart transplantation. INTERVENTIONS: A total of 609 adult heart transplant recipients were divided into 2 cohorts: patients who did not receive T3 (no T3 group, from 2009 to 2014), and patients who received T3 (T3 group, from 2015 to 2019). Propensity-adjusted logistic regression was performed to assess the association between T3 supplementation and PGD. MEASUREMENTS AND MAIN RESULTS: After applying exclusion criteria and propensity-score analysis, the final cohort included 461 patients. The incidence of PGD was not significantly different between the groups (33.9% no T3 group v 40.8% T3 group; p = 0.32). Mortality at 30 days (3% no T3 group v 2% T3 group; p = 0.53) and 1 year (10% no T3 group v 12% T3 group; p = 0.26) were also not significantly different. When assessing the severity of PGD, there were no differences in the groups' rates of moderate PGD (not requiring mechanical circulatory support other than an intra-aortic balloon pump) or severe PGD (requiring mechanical circulatory support other than an intra-aortic balloon pump). However, segmented time regression analysis revealed that patients in the T3 group were less likely to develop severe PGD. CONCLUSIONS: These findings indicated that recipient single-dose thyroid hormone administration may not protect against the development of PGD, but may attenuate the severity of PGD.

Perioperative Fluid Management.

The medical complexity of the geriatric patients has been steadily rising. Still, as outcomes of surgical procedures in the elderly are improving, centers are pushing boundaries. There is also a growing appreciation of the importance of perioperative fluid management on postoperative outcomes, especially in the elderly. Optimal fluid management in this cohort is challenging due to the combination of age-related physiological changes in organ function, increased comorbid burden, and larger fluid shifts during more complex surgical procedures. The current state-of-the-art approach to fluid management in the perioperative period is outlined.

An Unusual Cause of End-Tidal Carbon Dioxide Rise During One-Lung Ventilation.

A relatively common problem that may arise during one-lung ventilation is elevation of end-tidal carbon dioxide (ETCO2), which has several potential etiologies. This case report describes a 69-year-old woman with carcinoid tumor undergoing a robotic left lower lobectomy complicated by an acute rise in ETCO2 during one-lung ventilation, without an immediately identifiable cause. Thorough evaluation revealed CO2 leak through an open bronchial lumen resulting in an artificially high ETCO2 reading. This case report demonstrates the importance of performing a comprehensive assessment during acute changes in ETCO2 while also considering changes in the surgical field, which may contribute to these findings.

Echocardiographic Evidence of Cardiac Atrophy in the Critically Ill.

The purpose of this explorative study is to determine if critically ill patients experience cardiac atrophy that can be quantified as a loss of left ventricular mass (LVM) and thus detected by echocardiography. DESIGN: Retrospective single-center cohort study. SETTING: Patients admitted to a tertiary medical center in Boston, MA. PATIENTS: Adult critically ill patients with ICU length of stay greater than or equal to 5 days. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We conducted a retrospective cohort study of 68 patients, of which 42 were included in the final analysis (mean age 60.9 ± 19.2 yr; 47.6% male). The median length of ICU stay was 11.3 days (interquartile range, 6.8-20.1 d). A decrease in mean LVM over the course of admission for critical illness was observed (median 189.11 g [162.82-240.20 g] vs 176.69 g [142.37-226.26 g]; p = 0.01). After adjusting for sex, age, fluid balance, ICU type, dietary orders, time between echocardiograms, and vasopressor use, this decrease in LVM remained consistent (mean difference, -21.30 g; 95% CI, -41.85 to -0.74; p = 0.04). Relative wall thickness (RWT) did not change during admission. CONCLUSIONS: These data reveal that a loss of LVM is present in patients over their ICU stay without a corresponding change in RWT, consistent with cardiac atrophy. Future prospective studies are needed to confirm these findings and identify possible sequelae of this finding.

Anesthetics to Prevent Lung Injury in Cardiac Surgery: A Randomized Controlled Trial.

OBJECTIVES: To investigate if sevoflurane based anesthesia is superior to propofol in preventing lung inflammation and preventing postoperative pulmonary complications. DESIGN: Randomized controlled trial. SETTING: Single tertiary care university hospital. PARTICIPANTS: Forty adults undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: Patients were randomized in a 1:1 ratio to anesthetic maintenance with sevoflurane or propofol. MEASUREMENTS AND MAIN RESULTS: Blood and bronchoalveolar lavage fluid was sampled before and after bypass to measure pulmonary inflammation using a biomarker panel. The change in bronchoalveolar lavage concentration of tumor necrosis factor alpha (TNFα) was the primary outcome. Secondary outcomes included lung inflammation defined as changes in other biomarkers and postoperative pulmonary complications. There were no significant differences between groups in the change in bronchoalveolar lavage TNFα concentration (median [IQR] change, 17.24 [1.11-536.77] v 101.51 [1.47-402.84] pg/mL, sevoflurane v propofol, p = 0.31). There was a significantly lower postbypass concentration of plasma interleukin 8 (median [IQR], 53.92 [34.5-55.91] v 66.92 [53.03-94.44] pg/mL, p = 0.04) and a significantly smaller postbypass increase in the plasma receptor for advanced glycosylation end products (median [IQR], 174.59 [73.59-446.06] v 548.22 [193.15-852.39] pg/mL, p = 0.03) in the sevoflurane group compared with propofol. The incidence of postoperative pulmonary complications was 100% in both groups, with high rates of pleural effusion (17/18 [94.44%] v 19/22 [86.36%], p = 0.39) and hypoxemia (16/18 [88.88%] v 22/22 [100%], p = 0.11). CONCLUSIONS: Sevoflurane anesthesia during cardiac surgery did not consistently prevent lung inflammation or prevent postoperative pulmonary complications compared to propofol. There were significantly lower levels of 2 plasma biomarkers specific for lung injury and inflammation in the sevoflurane group.

Bleeding and thrombotic events in adults supported with venovenous extracorporeal membrane oxygenation: an ELSO registry analysis.

PURPOSE: This study aimed at analyzing the prevalence, mortality association, and risk factors for bleeding and thrombosis events (BTEs) among adults supported with venovenous extracorporeal membrane oxygenation (VV-ECMO). METHODS: We queried the Extracorporeal Life Support Organization registry for adults supported with VV-ECMO from 2010 to 2017. Multivariable logistic regression modeling was used to assess the association between BTEs and in-hospital mortality and the predictors of BTEs. RESULTS: Among 7579 VV-ECMO patients meeting criteria, 40.2% experienced ≥ 1 BTE. Thrombotic events comprised 54.9% of all BTEs and were predominantly ECMO circuit thrombosis. BTE rates decreased significantly over the study period (p < 0.001). The inpatient mortality rate was 34.9%. Bleeding events (1.69 [1.49-1.93]) were more strongly associated with in-hospital mortality than thrombotic events (1.23 [1.08-1.41]) p < 0.01 for both. The BTEs most strongly associated with mortality were ischemic stroke (4.50 [2.55-7.97]) and medical bleeding, including intracranial (5.71 [4.02-8.09]), pulmonary (2.02 [1.54-2.67]), and gastrointestinal (1.54 [1.2-1.98]) hemorrhage, all p < 0.01. Risk factors for bleeding included acute kidney injury and pre-ECMO vasopressor support and for thrombosis were higher weight, multisite cannulation, pre-ECMO arrest, and higher PaCO2 at ECMO initiation. Longer time on ECMO, younger age, higher pH, and earlier year of support were associated with bleeding and thrombosis. CONCLUSIONS: Although decreasing over time, BTEs remain common during VV-ECMO and have a strong, cumulative association with in-hospital mortality. Thrombotic events are more frequent, but bleeding carries a higher risk of inpatient mortality. Differential risk factors for bleeding and thrombotic complications exist, raising the possibility of a tailored approach to VV-ECMO management.

Renal-Resistive Index for Prediction of Acute Kidney Injury in the Setting of Aortic Insufficiency.

Acute kidney injury (AKI) is a common postoperative complication after cardiac surgery with cardiopulmonary bypass (CPB), and leads to significant morbidity, mortality, and cost. Although early recognition and management of AKI may reduce the burden of renal disease, reliance on serum creatinine accumulation to confidently diagnose it leads to a significant and important delay (up to 48 hours). Hence, a search for earlier AKI biomarkers is warranted. The renal-resistive index (RRI) is a promising early AKI biomarker that reflects intrarenal arterial pulsatility as reflected by the peak systolic and end-diastolic blood velocities divided by the peak systolic velocity. During cardiac surgery, post-CPB elevation of RRI is correlated with renal injury. The RRI is influenced by intrarenal and extrarenal factors, as well as different hemodynamic states. Understanding its limitations may increase its usefulness as an early AKI biomarker. For example, tachycardia or aortic stenosis typically results in a lower RRI, whereas bradycardia or increased systemic pulse pressure (as seen with aortic insufficiency) are associated with a higher RRI, unrelated to any intrarenal effects. In this E-Challenge, the authors present two cases in which the RRI was used to evaluate a patient's risk of developing AKI.

Development of an Instrument for Preoperative Prediction of Adverse Discharge in Patients Scheduled for Cardiac Surgery.

OBJECTIVE: Inability of home discharge occurs in nearly a third of patients undergoing cardiac surgery and is associated with increased mortality. The authors aimed to evaluate the incidence and risk factors for adverse discharge disposition (ADD) after cardiac surgery and develop a prediction tool for preoperative risk assessment. DESIGN: This retrospective cohort study included adult patients undergoing cardiac surgery between 2010 and 2018. The primary outcome was ADD, defined as in-hospital mortality, discharge to a skilled nursing facility, or transfer to a long-term care hospital. The authors created a prediction tool using stepwise backward logistic regression and used 5-fold and leave-one-out cross-validation. SETTING: University hospital network. PARTICIPANTS: Adult patients living at home prior to surgery, who underwent coronary artery bypass grafting and/or valve procedures at the authors' institution. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 3,760 patients were included in the final study cohort. The observed rate of ADD was 33.3%. The prediction model showed good discrimination and accuracy, with C-statistic of 0.78 (95% confidence interval [CI] 0.76-0.79) and unmodified Brier score of 0.177 (reliability 0.001). The final model comprised 14 predictors. Patients who experienced ADD were more likely to be older, of female sex, to have had higher length of hospital stay prior to surgery, and to have undergone emergency surgery. CONCLUSIONS: The authors present an instrument for prediction of loss of the ability to live independently in patients undergoing cardiac surgery. The authors' score may be useful in identifying high-risk patients such that earlier coordination of care can be initiated in this vulnerable patient population.

Interventional Pulmonology: A Brave New World.

Interventional pulmonology is a dynamic and evolving field in respiratory medicine. Advances have improved the ability to diagnose and manage diseases of the airways. A shift toward early detection of malignant disease has generated a focus on innovative diagnostic techniques. With patient populations living longer with malignant and benign diseases, the role for interventional bronchoscopy has grown. In cancer groups, novel immunotherapies have improved the prospects of clinical outcomes and reignited a focus on optimizing patient performance status to enable access to anticancer therapy. This review discusses current and emerging diagnostic modalities and therapeutic approaches available to manage airway diseases.

Perioperative Considerations for Tracheostomies in the Era of COVID-19.

The morbidity, mortality, and blistering pace of transmission of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an unprecedented worldwide health crisis. Coronavirus disease 2019 (COVID-19), the disease produced by SARS-CoV-2 infection, is remarkable for persistent, severe respiratory failure requiring mechanical ventilation that places considerable strain on critical care resources. Because recovery from COVID-19-associated respiratory failure can be prolonged, tracheostomy may facilitate patient management and optimize the use of mechanical ventilators. Several important considerations apply to plan tracheostomies for COVID-19-infected patients. After performing a literature review of tracheostomies during the severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks, we synthesized important learning points from these experiences and suggested an approach for perioperative teams involved in these procedures during the COVID-19 pandemic. Multidisciplinary teams should be involved in decisions regarding timing and appropriateness of the procedure. As the theoretical risk of disease transmission is increased during aerosol-generating procedures (AGPs), stringent infectious precautions are warranted. Personal protective equipment (PPE) should be available and worn by all personnel present during tracheostomy. The number of people in the room should be limited to those absolutely necessary. Using the most experienced available operators will minimize the total time that staff is exposed to an infectious aerosolized environment. An approach that secures the airway in the safest and quickest manner will minimize the time any part of the airway is open to the environment. Deep neuromuscular blockade (train-of-four ratio = 0) will facilitate surgical exposure and prevent aerosolization due to patient movement or coughing. For percutaneous tracheostomies, the bronchoscopist should be able to reintubate if needed. Closed-loop communication must occur at all times among members of the team. If possible, after tracheostomy is performed, waiting until the patient is virus-free before changing the cannula or downsizing may reduce the chances of health care worker infection. Tracheostomies in COVID-19 patients present themselves as extremely high risk for all members of the procedural team. To mitigate risk, systematic meticulous planning of each procedural step is warranted along with strict adherence to local/institutional protocols.

Automated Spectral Doppler Profile Tracing.

OBJECTIVE: The authors hypothesized that automated tracings of both pulsed wave (PW) and continuous wave (CW) Doppler correlate well with manual measurements performed by an experienced echocardiographer. DESIGN: The authors performed a retrospective analysis of spectral Doppler profile measurements performed by automated software and an echocardiographer. SETTING: University hospital, single institution. PARTICIPANTS: The authors reviewed transesophageal echocardiographic examinations from patients undergoing transcatheter aortic valve (AV) replacement procedures at their institution. INTERVENTIONS: No interventions were performed solely for research purposes. MEASUREMENTS AND MAIN RESULTS: PW and CW spectral envelopes at the left ventricular outflow tract (LVOT) and AV were analyzed. Blinded, a board-certified echocardiographer performed manual measurements of the identical spectral envelopes. Peak velocities, mean gradients, and velocity time integrals (VTI) were collected. A total of 33 PW as well as 33 CW Doppler spectral envelopes were evaluated. There was no significant difference between the measurements provided by the automated software and manual tracings. LVOT PW VTI automated versus manual: 18.2 cm versus 15.9 cm, p = 0.11. AV CW VTI automated versus manual: 65.8 cm versus 64.8 cm, p = 0.90. AV CW mean gradient automated versus manual: 24.3 mmHg versus 23.4 mmHg, p = 0.84. AV CW peak velocity automated versus manual: 3.00 m/s versus 2.98 m/s, p = 0.93. Correlation coefficients were all above 0.9. CONCLUSIONS: Automated measurements of peak velocities, mean gradients, and VTI of spectral Doppler correlate closely with manual measurements performed by an experienced echocardiographer.