Severe Acute Blood Loss Anemia in Jehovah's Witnesses Undergoing Cardiac Surgery: Single Academic Center Experience.

OBJECTIVE: To determine the effect of severe acute blood loss anemia (ABLA) on postoperative outcomes in Jehovah's Witness (JW) patients undergoing cardiac surgery. DESIGN: This was a retrospective cohort study of adult JW patients undergoing cardiac surgery requiring cardiopulmonary bypass (CPB) between January 1998 and December 2018 at Barnes-Jewish Hospital in St. Louis, Missouri. SETTING: At a single tertiary academic center. PARTICIPANTS: Patients who were JWs undergoing cardiac surgery requiring CPB. INTERVENTIONS: Patients were divided into the following 2 groups: JW patients who developed severe ABLA (defined as postoperative hematocrit level <21), and patients who did not develop severe ABLA. MEASUREMENTS AND MAIN RESULTS: A total of 48 JW patients who underwent cardiac surgery between 2008 and 2018 were identified. Of these patients, 9 (18.8%) developed postoperative severe ABLA, and 39 (81.3%) did not. Severe ABLA was associated with increased postoperative mortality at 30-days, 90-days, and 1-year postoperatively, and a trend toward increased hospital length of stay. CONCLUSIONS: Severe ABLA after cardiac surgery was associated with higher mortality and a trend toward increased hospital length of stay among JW patients. More data are required to confirm the findings.

Concomitant surgical ablation for atrial fibrillation is associated with increased risk of acute kidney injury but improved late survival.

BACKGROUND: Acute kidney injury (AKI) after cardiac surgery remains a common complication that has been associated with increased morbidity and mortality. This study implemented Kidney Disease Improving Global Outcomes criteria to evaluate renal outcomes after concomitant surgical ablation for atrial fibrillation. METHODS: Patients with a history of atrial fibrillation who underwent elective cardiac surgery at our institution from 2008 to 2018 were retrospectively reviewed. Those with preoperative renal dysfunction were excluded. Patients were classified as those who underwent concomitant Cox-Maze IV (CMP-IV) (n = 376) or no surgical ablation (n = 498). Nearest neighbor 1:1 propensity matching was conducted on fourteen covariates. AKI was evaluated by mixed effects logistic regression analysis. Long-term survival was evaluated by proportional hazards regression. RESULTS: Propensity matching yielded 308 patients in each group (n = 616). All preoperative variables were similar between groups. The concomitant CMP-IV group had a greater incidence of AKI: 32% (n = 99) versus 16% (n = 49), P < .001. After accounting for bypass time and nonablation operations on mixed effects analysis, concomitant CMP-IV was associated with increased risk of AKI (odds ratio, 1.89; confidence interval, 1.12-3.18; P = .017). While AKI was associated with decreased late survival (P < .001), patients who received a concomitant CMP-IV maintained superior 7-year survival to patients who received no ablation (P < .001). No patients required permanent dialysis. CONCLUSIONS: Concomitant CMP-IV was independently associated with increased risk of AKI in the acute postoperative period. However, the long-term risks of AKI were offset by the significant survival benefit of CMP-IV. Concerns regarding new-onset renal dysfunction should not prohibit recommendation of this procedure in appropriate patients.

A 3-hour fast-track extubation protocol for early extubation after cardiac surgery.

Objectives: Early extubation after cardiac surgery improves outcomes and reduces cost. We investigated the effect of a multidisciplinary 3-hour fast-track protocol on extubation, intensive care unit length of stay time, and reintubation rate after a wide range of cardiac surgical procedures. Methods: We performed an observational study of 472 adult patients undergoing cardiac surgery at a large academic institution. A multidisciplinary 3-hour fast-track protocol was applied to a wide range of cardiac procedures. Data were collected 4 months before and 6 months after protocol implementation. Cox regression model assessed factors associated with extubation time and intensive care unit length of stay. Results: A total of 217 patients preprotocol implementation and 255 patients postprotocol implementation were included. Baseline characteristics were similar except for the median procedure time and dexmedetomidine use. The median extubation time was reduced by 44% (4:43 hours vs 3:08 hours; P < .001) in the postprotocol group. Extubation within 3 hours was achieved in 49.4% of patients in the postprotocol group compared with 25.8% patients in the preprotocol group; P < .001. There was no statistically significant difference in the intensive care unit length of stay after controlling for other factors. Early extubation was associated with only 1 patient requiring reintubation in the postprotocol group. Conclusions: The multidisciplinary 3-hour fast-track extubation protocol is a safe and effective tool to further reduce the duration of mechanical ventilation after a wide range of cardiac surgical procedures. The protocol implementation did not decrease the intensive care unit length of stay.

Incidence and prediction of intraoperative and postoperative cardiac arrest requiring cardiopulmonary resuscitation and 30-day mortality in non-cardiac surgical patients.

BACKGROUND: The incidence, prediction and mortality outcomes of intraoperative and postoperative cardiac arrest requiring cardiopulmonary resuscitation (CPR) in surgical patients are under investigated and have not been studied concurrently in a single study. METHODS: A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program data between 2008 and 2012. Firth's penalized logistic regression was used to study the incidence and identify risk factors for intra- and postoperative CPR and 30-day mortality. simplified prediction model was constructed and internally validated to predict the studied outcomes. RESULTS: Among about 1.86 million non-cardiac operations, the incidence rate of intraoperative CPR was 0.03%, and for postoperative CPR was 0.33%. The 30-day mortality incidence rate was 1.25%. The incidence rate of events decreased overtime between 2008-2012. Of the 29 potential predictors, 14 were significant for intraoperative CPR, 23 for postoperative CPR, and 25 for 30-day mortality. The five strongest predictors (highest odd ratios) of intraoperative CPR were the American Society of Anesthesiologists (ASA) physical status, Systemic Inflammatory Response Syndrome (SIRS)/sepsis, surgery type, urgent/emergency case and anesthesia technique. Intraoperative CPR, ASA, age, functional status and end stage renal disease were the most significant predictors for postoperative CPR. The most significant predictors of 30-day mortality were ASA, age, functional status, SIRS/sepsis, and disseminated cancer. The predictions with the simplified five-factor model performed well and was comparable to the full prediction model. Postoperative cardiac arrest requiring CPR, compared to intraoperative, was associated with much higher mortality. CONCLUSIONS: The incidence of cardiac arrest requiring CPR in surgical patients decreased overtime. Risk factors for intraoperative CPR, postoperative CPR and perioperative mortality are overlapped. We proposed a simplified approach compromised of five-factor model to identify patients at high risk. Postoperative, compare to intraoperative, cardiac arrest requiring CPR was associated with much higher mortality.

Etiology of Acute Coronary Syndrome after Noncardiac Surgery.

BACKGROUND: The objective of this investigation was to determine the etiology of perioperative acute coronary syndrome with a particular emphasis on thrombosis versus demand ischemia. METHODS: In this retrospective cohort study, adult patients were identified who underwent coronary angiography for acute coronary syndrome within 30 days of noncardiac surgery at a major tertiary hospital between January 2008 and July 2015. Angiograms were independently reviewed by two interventional cardiologists who were blinded to clinical data and outcomes. Acute coronary syndrome was classified as ST-elevation myocardial infarction, non-ST-elevation myocardial infarction, or unstable angina; myocardial infarctions were adjudicated as type 1 (plaque rupture), type 2 (demand ischemia), or type 4b (stent thrombosis). RESULTS: Among 215,077 patients screened, 146 patients were identified who developed acute coronary syndrome: 117 were classified as non-ST-elevation myocardial infarction (80.1%); 21 (14.4%) were classified as ST-elevation myocardial infarction, and 8 (5.5%) were classified as unstable angina. After coronary angiography, most events were adjudicated as demand ischemia (type 2 myocardial infarction, n = 106, 72.6%) compared to acute coronary thrombosis (type 1 myocardial infarction, n = 37, 25.3%) and stent thrombosis (type 4B, n = 3, 2.1%). Absent or only mild, nonobstructive coronary artery disease was found in 39 patients (26.7%). In 14 patients (9.6%), acute coronary syndrome was likely due to stress-induced cardiomyopathy. Aggregate 30-day and 1-yr mortality rates were 7 and 14%, respectively. CONCLUSIONS: The dominant mechanism of perioperative acute coronary syndrome in our cohort was demand ischemia. A subset of patients had no evidence of obstructive coronary artery disease, but findings were consistent with stress-induced cardiomyopathy.

Are high-sensitivity cardiac troponin I values stable between preoperative visit and day of non-cardiac surgery?

BACKGROUND: It is unclear if cardiac troponin values are stable in patients prior to undergoing non-cardiac surgery, or if they tend to rise towards the day of surgery. METHODS: In this small pilot study (n=18) among patients with cardiac risk undergoing non-cardiac surgery, we determined if high-sensitivity cardiac troponin I (hscTnI) changes between the preoperative clinic visit and the day of surgery. HscTnI was measured on an Abbott Architect STAT (Abbott Laboratories, USA) platform. RESULTS: The mean duration between preoperative clinic visit and day of surgery was 8.7±2.8 (SD) days. Median hscTnI was 3.4ng/L [2.0-4.8, IQR] at the preoperative visit and 2.8ng/L [2.3-4.4] on the day of surgery (mean difference-0.24ng/L, 95% CI - 0.73 to 0.24ng/L, p=0.30). Only one patient had a large change (>50%) along with symptoms. DISCUSSION: Evidence from this small study suggests that cardiac troponin values are stable in most high-risk patients, absent clinical events, within 10days prior to non-cardiac surgery.

High-Sensitivity Cardiac Troponin T Improves the Diagnosis of Perioperative MI.

BACKGROUND: The diagnosis of myocardial infarction (MI) after noncardiac surgery has traditionally relied on using relatively insensitive contemporary cardiac troponin (cTn) assays. We hypothesized that using a recently introduced novel high-sensitivity cTnT (hscTnT) assay would increase the detection rate of perioperative MI. METHODS: In this ancillary study of the Vitamins in Nitrous Oxide trial, readjudicated incidence rates of myocardial injury (new isolated cTn elevation) and MI were compared when diagnosed by contemporary cTnI versus hscTnT. We probed various relative (eg, >50%) or absolute (eg, +5 ng/L) hscTnT change metrics. Inclusion criteria for this ancillary study were the presence of a baseline and at least 1 postoperative hscTnT value. RESULTS: Among 605 patients, 70 patients (12%) had electrocardiogram changes consistent with myocardial ischemia; 82 patients (14%) had myocardial injury diagnosed by contemporary cTnI, 31 (5.1%) of which had an adjudicated MI. After readjudication, 67 patients (11%) were diagnosed with MI when using hscTnT, a 2-fold increase. Incidence rates of postoperative myocardial injury ranged from 12% (n = 73) to 65% (n = 393) depending on the hscTnT metric used. Incidence rates of MI using various hscTnT change metrics and the presence of ischemic electrocardiogram changes, but without event adjudication, ranged from 3.6% (n = 22) to 12% (n = 74), a >3-fold difference. New postoperative hscTnT elevation, either by absolute or relative hscTnT change metric, was associated with an up to 5-fold increase in 6-month mortality. CONCLUSIONS: The use of hscTnT compared to contemporary cTnI increases the detection rate of perioperative MI by a factor of 2. Using different absolute or relative hscTnT change metrics may lead to under- or overdiagnosis of perioperative MI.

Dexamethasone and Clonidine, but not Epinephrine, Prolong Duration of Ropivacaine Brachial Plexus Blocks, Cross-Sectional Analysis in Outpatient Surgery Setting.

OBJECTIVE: The primary aim of this study is to determine the effect of adding dexamethasone, clonidine or both with and without epinephrine to ropivacaine and bupivacaine brachial plexus blocks. DESIGN: Observational study of prospectively collected data. SETTING: Single academic outpatient surgery center. METHODS: We evaluated 5,515 patient entries who received brachial plexus block (BPB). Multiple, rescue, unsuccessful, and distal nerve blocks of the upper extremity were excluded. The duration was calculated from the time the block was performed until the resolution of the block by patient report. Block durations were compared using Analysis of Variance. RESULTS: After exclusions, 3,706 nerve blocks were analyzed. The median concentration of ropivacaine used was 0.5%. Both clonidine and dexamethasone significantly increased block duration by 1.1 and 3.0 hours, respectively. Combining clonidine and dexamethasone with ropivacaine increased block duration by 6.2 hours (p<0.001) when compared to ropivacaine alone. Dexamethasone and Clonidine increased block duration by 5.2 hours (p<0.001) when compared to clonidine alone and by 3.2 hours (p<0.001) compared to dexamethasone alone. The addition of epinephrine to any of the adjuvants made no statistically significant difference to the duration of action except when it was added to dexamethasone. SUMMARY: For brachial plexus blocks, epinephrine did not affect the duration of analgesia when added to ropivacaine. Epinephrine did not enhance the observed increase of block duration induced by clonidine or the combination of clonidine and dexamethasone. The most block duration enhancement was observed when combination of clonidine and dexamethasone were added to ropivacaine.

Improving Prediction of Postoperative Myocardial Infarction With High-Sensitivity Cardiac Troponin T and NT-proBNP.

BACKGROUND: This study sought to determine whether preoperatively measured high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) improve cardiac risk prediction in patients undergoing major noncardiac surgery compared with the standard risk indices. METHODS: In this ancillary study to the Vitamins in Nitrous Oxide trial, patients were included who had preoperative hs-cTnT and NT-proBNP measured (n = 572). Study outcome was the incidence of postoperative myocardial infarction (MI) within the first 3 postoperative days. hs-cTnT was considered elevated if >14 ng/L and NT-proBNP if >300 ng/L. Additional cutoff values were investigated on the basis of receiver operating characteristic statistics. Biomarker risk prediction was compared with Lee's Revised Cardiac Risk Index (RCRI) with the use of standard methods and net reclassification index. RESULTS: The addition of hs-cTnT (>14 ng/L) and NT-proBNP (>300 ng/L) to RCRI significantly improved the prediction of postoperative MI (event rate 30/572 [5.2%], Area under the receiver operating characteristic curve increased from 0.590 to 0.716 with a 0.66 net reclassification index [95% confidence interval 0.32-0.99], P < .001). The use of 108 ng/L as a cutoff for NT-proBNP improved sensitivity compared with 300 ng/L (0.87 vs 0.53). Sensitivity, specificity, positive, and negative predictive value for hs-cTnT were 0.70, 0.60, 0.09, and 0.97 and for NT-proBNP were 0.53, 0.68, 0.08, and 0.96. CONCLUSIONS: The addition of cardiac biomarkers hs-cTnT and NT-proBNP to RCRI improves the prediction of adverse cardiac events in the immediate postoperative period after major noncardiac surgery. The high negative predictive value of preoperative hs-cTnT and NT-proBNP suggest usefulness as a "rule-out" test to confirm low risk of postoperative MI.

Effects of regional versus general anesthesia on outcomes after total hip arthroplasty: a retrospective propensity-matched cohort study.

BACKGROUND: Many orthopaedic surgical procedures can be performed with either regional or general anesthesia. We hypothesized that total hip arthroplasty with regional anesthesia is associated with less postoperative morbidity and mortality than total hip arthroplasty with general anesthesia. METHODS: This retrospective propensity-matched cohort study utilizing the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database included patients who had undergone total hip arthroplasty from 2007 through 2011. After matching, logistic regression was used to determine the association between the type of anesthesia and deep surgical site infections, hospital length of stay, thirty-day mortality, and cardiovascular and pulmonary complications. RESULTS: Of 12,929 surgical procedures, 5103 (39.5%) were performed with regional anesthesia. The adjusted odds for deep surgical site infections were significantly lower in the regional anesthesia group than in the general anesthesia group (odds ratio [OR] = 0.38; 95% confidence interval [CI] = 0.20 to 0.72; p < 0.01). The hospital length of stay (geometric mean) was decreased by 5% (95% CI = 3% to 7%; p < 0.001) with regional anesthesia, which translates to 0.17 day for each total hip arthroplasty. Regional anesthesia was also associated with a 27% decrease in the odds of prolonged hospitalization (OR = 0.73; 95% CI = 0.68 to 0.89; p < 0.001). The mortality rate was not significantly lower with regional anesthesia (OR = 0.78; 95% CI = 0.43 to 1.42; p > 0.05). The adjusted odds for cardiovascular complications (OR = 0.61; 95% CI = 0.44 to 0.85) and respiratory complications (OR = 0.51; 95% CI = 0.33 to 0.81) were all lower in the regional anesthesia group. CONCLUSIONS: Compared with general anesthesia, regional anesthesia for total hip arthroplasty was associated with a reduction in deep surgical site infection rates, hospital length of stay, and rates of postoperative cardiovascular and pulmonary complications. These findings could have an important medical and economic impact on health-care practice.

Contaminated heparin and outcomes after cardiac surgery: a retrospective propensity-matched cohort study.

BACKGROUND: During 2007 and 2008 it is likely that millions of patients in the US received heparin contaminated (CH) with oversulfated chondroitin sulfate, which was associated with anaphylactoid reactions. We tested the hypothesis that CH was associated with serious morbidity, mortality, intensive care unit (ICU) stay and heparin-induced thrombocytopenia following adult cardiac surgery. METHODS AND FINDINGS: We conducted a single center, retrospective, propensity-matched cohort study during the period of CH and the equivalent time frame in the three preceding or the two following years. Perioperative data were obtained from the institutional record of the Society of Thoracic Surgeons National Database, for which the data collection is prospective, standardized and performed by independent investigators. After matching, logistic regression was performed to evaluate the independent effect of CH on the composite adverse outcome (myocardial infarction, stroke, pneumonia, dialysis, cardiac arrest) and on mortality. Cox regression was used to determine the association between CH and ICU length of stay. The 1∶5 matched groups included 220 patients potentially exposed to CH and 918 controls. There were more adverse outcomes in the exposed cohort (20.9% versus 12.0%; difference  =  8.9%; 95% CI 3.6% to 15.1%, P < 0.001) with an odds ratio for CH of 2.0 (95% CI, 1.4 to 3.0, P < 0.001). In the exposed group there was a non-significant increase in mortality (5.9% versus 3.5%, difference = 2.4%; 95% CI, -0.4 to 3.5%, P  =  0.1), the median ICU stay was longer by 14.1 hours (interquartile range -26.6 to 79.8, S = 3299, P = 0.0004) with an estimated hazard ratio for CH of 1.2 (95% CI, 1.0 to 1.4, P = 0.04). There was no difference in nadir platelet counts between cohorts. CONCLUSIONS: The results from this single center study suggest the possibility that contaminated heparin might have contributed to serious morbidity following cardiac surgery.

Successful lumbar epidural catheter placement through a lower back lipoma.

Structural abnormalities of the lumbar spine or the overlying structures may represent a relative contraindication or technical difficulty to neuraxial anesthesia. We report a case of successful epidural catheter placement through a lower back lipoma for vascular bypass surgery of the lower extremity.