Blood bupivacaine concentrations after pecto-serratus and serratus anterior plane injections of plain and liposomal bupivacaine in robotically-assisted mitral valve surgery: Sub-study of a randomized trial.

STUDY OBJECTIVE: To investigate the timing of peak blood concentrations and potential toxicity when using a combination of plain and liposomal bupivacaine for thoracic fascial plane blocks. DESIGN: Pharmacokinetic analysis. SETTING: Operating room. PATIENTS: Eighteen adult patients undergoing robotically-assisted mitral valve surgery. INTERVENTIONS: Ultrasound-guided pecto-serratus and serratus anterior plane blocks using a mixture of 0.5% bupivacaine HCl up to 2.5 mg/kg and liposomal bupivacaine up to 266 mg. MEASUREMENTS: Arterial plasma bupivacaine concentration. MAIN RESULTS: Samples from 13 participants were analyzed. There was substantial inter-patient variability in plasma concentrations. A geometric mean maximum bupivacaine concentration was 1492 ng/ml (range 660 to 4650 ng/ml) at median time of 30 min after injection. In 4/13 (31%) patients, plasma bupivacaine concentrations exceeded our predefined 2000 ng/ml toxic threshold. A second much smaller peak was observed about 32 h after the injection. No obvious signs of local anesthetic toxicity were observed. CONCLUSIONS: Combined injection of plain and liposomal bupivacaine for pecto-serratus/serratus anterior plane blocks produced a biphasic pattern, with the highest arterial plasma concentrations observed within 30 min. Maximum concentrations exceeded the potential toxic threshold in nearly a third of patients, but without clinical evidence of toxicity. Clinicians should not assume that routine combinations of plain and liposomal bupivacaine for thoracic fascial plane blocks are inherently safe.

Processing speed test and 30-day readmission in elderly non-cardiac surgery patients- A retrospective study.

Background and Aims: Preoperative cognitive function screening can help identify high-risk patients, but resource-intensive testing limits its widespread use. A novel self-administered tablet computer-based Processing Speed Test (PST) was used to assess cognitive "executive" function in non-cardiac surgery patients, but the relationship between preoperative test scores and postoperative outcomes is unclear. The primary outcome was a composite of 30-day readmission/death. The secondary outcome was a collapsed composite of discharge to a long-term care facility/death. Exploratory outcomes were 1) time to discharge alive, 2) 1-year mortality and 3) a collapsed composite of postoperative complications. Methods: This retrospective study, after approval, was conducted in elective non-cardiac surgery patients ≥65 years old. We assessed the relationship between processing speed test scores and primary/secondary outcomes using multivariable logistic regression, adjusting for potential confounding variables. Results: Overall 1568 patients completed the PST, and the mean ± standard deviation test score was 33 ± 10. The higher PST score is associated with better executive function. A 10-unit increase in the test score was associated with an estimated 19% lower 30-day readmission/death odds, with an odds ratio (OR) and 95% confidence interval (CI) of 0.81 (0.68, 0.96) (P = 0.015). Similarly, 10-unit increase in test score was associated with an estimated 26% lower odds of long-term care need/death, with OR (95% CI) of 0.74 (0.61, 0.91) (P = 0.004). We also found statistically significant associations between the test scores and time to discharge alive and to 1-year mortality, however, not with a composite of postoperative complications. Conclusion: Elderly non-cardiac surgery patients with better PST scores were less likely to be readmitted, need long-term care after discharge or die within 30 days. Preoperative assessment of cognitive function using a simple self-administered test is feasible and may guide perioperative care.

Serratus anterior and pectoralis plane blocks for robotically assisted mitral valve repair: a randomised clinical trial.

BACKGROUND: Minimally invasive cardiac surgery provokes substantial pain and therefore analgesic consumption. The effect of fascial plane blocks on analgesic efficacy and overall patient satisfaction remains unclear. We therefore tested the primary hypothesis that fascial plane blocks improve overall benefit analgesia score (OBAS) during the initial 3 days after robotically assisted mitral valve repair. Secondarily, we tested the hypotheses that blocks reduce opioid consumption and improve respiratory mechanics. METHODS: Adults scheduled for robotically assisted mitral valve repairs were randomised to combined pectoralis II and serratus anterior plane blocks or to routine analgesia. The blocks were ultrasound-guided and used a mixture of plain and liposomal bupivacaine. OBAS was measured daily on postoperative Days 1-3 and were analysed with linear mixed effects modelling. Opioid consumption was assessed with a simple linear regression model and respiratory mechanics with a linear mixed model. RESULTS: As planned, we enrolled 194 patients, with 98 assigned to blocks and 96 to routine analgesic management. There was neither time-by-treatment interaction (P=0.67) nor treatment effect on total OBAS over postoperative Days 1-3 with a median difference of 0.08 (95% confidence interval [CI]: -0.50 to 0.67; P=0.69) and an estimated ratio of geometric means of 0.98 (95% CI: 0.85-1.13; P=0.75). There was no evidence of a treatment effect on cumulative opioid consumption or respiratory mechanics. Average pain scores on each postoperative day were similarly low in both groups. CONCLUSIONS: Serratus anterior and pectoralis plane blocks did not improve postoperative analgesia, cumulative opioid consumption, or respiratory mechanics during the initial 3 days after robotically assisted mitral valve repair. CLINICAL TRIAL REGISTRATION: NCT03743194.

Relative contributions of anaemia and hypotension to myocardial infarction and renal injury: Post hoc analysis of the POISE-2 trial.

BACKGROUND: Hypotension and postoperative anaemia are associated with myocardial and renal injury after noncardiac surgery, but the interaction between them remains unknown. OBJECTIVES: To test the hypothesis that a double-hit of postoperative anaemia and hypotension synergistically worsens a 30-day composite of myocardial infarction (MI) and mortality and acute kidney injury (AKI). Characterising the interaction when hypotension and anaemia occur at same time on myocardial infarction and acute kidney injury. DESIGN: Post hoc analysis of the POISE-2 trial. SETTING: Patients were enrolled between July 2010 and December 2013 at 135 hospitals in 23 countries. PATIENTS: Adults at least 45 years old with known or suspected cardiovascular disease. We excluded patients without available postoperative haemoglobin measurements or hypotension duration records. Exposures were the lowest haemoglobin concentration and the average daily duration of SBP less than 90 mmHg within the first four postoperative days. MAIN OUTCOME MEASURES: The primary outcome was a collapsed composite of nonfatal MI and all-cause mortality during the initial 30 postoperative days; our secondary outcome was AKI. RESULTS: We included 7940 patients. The mean ±â€ŠSD lowest postoperative haemoglobin was 10 ±â€Š2 g dl -1 , and 24% of the patients had SBP less than 90 mmHg with daily duration ranging from 0 to 15 h. Four hundred and nine (5.2%) patients had an infarction or died within 30 postoperative days, and 417 (6.4%) patients developed AKI. Lowest haemoglobin concentrations less than 11 g dl -1 , and duration of SBP less than 90 mmHg was associated with greater hazard of composite outcome of nonfatal MI and all-cause mortality, as well as with AKI. However, we did not find significant multiplicative interactions between haemoglobin splines and hypotension duration on the primary composite or on AKI. CONCLUSION: Postoperative anaemia and hypotension were meaningfully associated with both our primary composite and AKI. However, lack of significant interaction suggests that the effects of hypotension and anaemia are additive rather than multiplicative. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01082874.

Chest pain in patients recovering from noncardiac surgery: A retrospective analysis.

STUDY OBJECTIVE: Chest pain is relatively common postoperatively. Myocardial infarction (MI) is one cause of chest pain after surgery, but chest pain also results from less severe conditions. Because of its potential severity, chest pain usually prompts the activation of Rapid Response Systems (RRS). While chest pain is a cardinal symptom of myocardial ischemia in the non-surgical setting, the significance and relevance of chest pain after noncardiac surgery remains unclear. DESIGN: We conducted a retrospective analysis of noncardiac surgical inpatients for whom postoperative chest pain triggered our multidisciplinary RRS. SETTING: Surgical wards at Cleveland Clinic, Cleveland, OH. PATIENTS: Postsurgical patients after noncardiac surgery in whom the RSS system was activated for chest pain. INTERVENTIONS: RRS specified interventions like ECG readings, troponin measurements, transfer to ICU. MEASUREMENTS: Our primary outcome was MI. Secondary outcomes included the proportion of patients who had an ECG performed, troponin measurements, echocardiography, cardiac catheterization, and were admitted to the Intensive Care Unit (ICU). MAIN RESULTS: 5850 surgical patients experienced postoperative chest pain and triggered an RRS activation between 2009 and 2019. A total of 3110 patients had troponin T measured within 6 h after RRS activation, and 538 of them (17%) had elevated troponin, meeting the Fourth Universal Definition criteria for MI. Additionally, 2 patients had ST-segment elevation infarction (STEMI) without troponin measurement. Among the 540 patients with MI, only 19 (3.5%) were diagnosed with a STEMI by ECG, 388 (72%) had echocardiography, 43 patients (8%) had cardiac catheterization, 8 patients (1.5%) required emergent cardiac surgery, and 424 (79%) were admitted to an ICU. CONCLUSION: Chest pain is a serious clinical sign, often indicating a postoperative myocardial infarction, and therefore should be taken seriously. Troponin screening should be routinely considered in postsurgical patients who report chest pain.

Diurnal blood pressure variation in adults after abdominal surgery-An observational cohort study.

OBJECTIVE: To describe the prevalence of various circadian blood pressure patterns in adults recovering from abdominal surgery, and to evaluate the association between loss of normal circadian variation in blood pressure and hypotension during the initial 2 postoperative days. DESIGN: A post-hoc analysis of data obtained from two randomized trials. SETTING: Operating rooms of the Cleveland Clinic. PATIENTS: Adults having abdominal surgery from 2015 to 2019 with at least one overnight stay. Participants were continuously monitored by wearable vital signs monitors starting in the post-anesthesia care unit and for the first 48 postoperative hours. INTERVENTIONS: None. The exposure of interest was the degree of nocturnal decrease in blood pressure - normal nocturnal decrease in blood pressure ("normal dipping", more than 10% decrease compared to day-time), no nocturnal decrease ("non-dipping", less than 10% nocturnal decrease), or nocturnal increase in blood pressure ("rising"). MEASUREMENTS: Postoperative hypotension, defined by the time weighted average (TWA) area under a mean arterial pressure (MAP) threshold of 70 mmHg. RESULTS: In total, 590 patients were eligible for analysis (mean(SD) age 50(15) years, 56% females, median [IQR] surgery duration 4.0 [2.7, 5.8] hours). Median TWA area under a MAP threshold of 70 mmHg was 0.96 (95%CI 0.59, 1.33) mmHg*minute per monitoring hour lower in patients with either no nocturnal blood pressure decrease (N = 317, 54%), or an increase in nocturnal blood pressure (N = 211, 36%), than in the reference group of patients with normal nocturnal decrease (N = 62, 11%), P < 0.001 for both. CONCLUSIONS: Abnormal diurnal blood pressure patterns are common in adults during the initial 2 days after abdominal surgery. Lack of normal night-time decrease in blood pressure is associated with less postoperative hypotension. Future studies should evaluate whether abnormal postoperative diurnal blood pressure patterns are associated with worse outcomes.

Does local anesthetic temperature affect the onset and duration of ultrasound-guided infraclavicular brachial plexus nerve block?: a randomized clinical trial.

BACKGROUND: Infraclavicular brachial plexus nerve block is a commonly performed anesthesiology technique in the upper extremity. Local anesthetics may be administered at different temperatures for both neuraxial and peripheral nerve blocks. We aimed to evaluate the effects of the temperature of the local anesthetic at the time of administration on the onset and duration of sensory and motor blocks in infraclavicular brachial plexus nerve block. METHODS: A total of 80 patients undergoing elective upper extremity surgery were randomly assigned to one of the following groups using a computer-based randomization software; low temperature (4 °C) (Group L, n = 26), room temperature (25 °C) (Group R, n = 27) and warmed (37 °C) (Group W, n = 27). A 1:1 mixture of 2% lidocaine and 0.5% bupivacaine was used as local anesthetic. Infraclavicular brachial plexus nerve block was performed under ultrasound guidance in all patients preoperatively. The onset and duration of sensory and motor blocks were recorded. RESULTS: Each group had different onset of motor (p < 0.001) and sensory (p < 0.001) blocks. The duration of motor block was similar between groups (p = 221). However, a significant difference was found in the duration of sensory block between group L (399.1 ± 40.8 min) and group R (379.6 ± 27.6 min) (p = 0.043). There was no complication related to nerve block procedure. CONCLUSIONS: The administration of the local anesthetic at lower temperatures may prolong the onset of both motor and sensory blocks in infraclavicular brachial plexus nerve block.