Impact of intrathecal morphine analgesia on the incidence of pulmonary complications after cardiac surgery: a single center propensity-matched cohort study

Intravenous Methadone versus Intrathecal Morphine as Part of an Enhanced Recovery After Cardiac Surgery Protocol on Postoperative Pain and Outcomes: A Retrospective Cohort Study

OBJECTIVES

Evaluate the effect of intravenous (IV) methadone versus intrathecal morphine (ITM) within an Enhanced Recovery After Cardiac Surgery (ERACS) pathway on postoperative pain and outcomes (length of hospital stay and postoperative complications) after cardiac surgery.

DESIGN

Retrospective cohort study.

SETTING

Two tertiary academic medical institutions within the same health system.

PARTICIPANTS

Eligible 289 adult patients undergoing elective cardiac surgery with an enhanced recovery pathway from January 2020 through July 2021.

INTERVENTIONS

Patients were administered ITM (0.25 mg) or IV methadone (0.1 mg/kg) if ITM was contraindicated. All patients were enrolled in an ERACS pathway using current Enhanced Recovery After Surgery society guidelines.

MEASUREMENTS AND MAIN RESULTS

Primary outcome measures included postoperative pain scores and opioid consumption measured as oral morphine equivalents. We analyzed patient demographics, procedural factors, intraoperative medications, and outcomes. Adjusted linear mixed models were fit to analyze associations between intervention and pain outcomes. ITM was associated with decrease in pain scores on postoperative day 0 after adjusting for clinical variables (average marginal effect, 0.49; 95% confidence interval, 0.002-0.977; p = 0.049). No difference in opioid consumption could be demonstrated between groups after adjusting for postoperative day and other variables of interest.

CONCLUSIONS

ITM when compared with IV methadone was associated with a decrease in pain scores without any difference in opioid consumption after elective cardiac surgery. Methadone can be considered as a safe and effective alternative to ITM for ERACS protocols. Future large prospective studies are needed to validate this finding and further improve analgesia and safety.

Pain management and opioid stewardship in adult cardiac surgery: Joint consensus report of the PeriOperative Quality Initiative and the Enhanced Recovery After Surgery Cardiac Society

BACKGROUND

Opioid-based anesthesia and analgesia is a traditional component of perioperative care for the cardiac surgery patient. Growing enthusiasm for Enhanced Recovery Programs (ERPs) coupled with evidence of potential harm associated with high-dose opioids suggests that we reconsider the role of opioids in cardiac surgery.

METHODS

An interdisciplinary North American panel of experts, using a structured appraisal of the literature and a modified Delphi method, derived consensus recommendations for optimal pain management and opioid stewardship for cardiac surgery patients. Individual recommendations are graded based on the strength and level of evidence.

RESULTS

The panel addressed 4 main topics: the harms associated with historical opioid use, the benefits of more targeted opioid administration, the use of nonopioid medications and techniques, and patient and provider education. A key principle that emerged is that opioid stewardship should apply to all cardiac surgery patients, entailing judicious and targeted use of opioids to achieve optimal analgesia with the fewest potential side effects. The process resulted in the promulgation of 6 recommendations regarding pain management and opioid stewardship in cardiac surgery, focused on avoiding the use of high-dose opioids, as well as encouraging more widespread application of foundational aspects of ERPs, such as the use of multimodal nonopioid medications and regional anesthesia techniques, formal patient and provider education, and structured system-level opioid prescription practices.

CONCLUSIONS

Based on the available literature and expert consensus, there is an opportunity to optimize anesthesia and analgesia for cardiac surgery patients. Although additional research is needed to establish specific strategies, core principles of pain management and opioid stewardship apply to the cardiac surgery population.

Practice Advisory for Preoperative and Intraoperative Pain Management of Cardiac Surgical Patients: Part 2

Pain after cardiac surgery is of moderate to severe intensity, which increases postoperative distress and health care costs, and affects functional recovery. Opioids have been central agents in treating pain after cardiac surgery for decades. The use of multimodal analgesic strategies can promote effective postoperative pain control and help mitigate opioid exposure. This Practice Advisory is part of a series developed by the Society of Cardiovascular Anesthesiologists (SCA) Quality, Safety, and Leadership (QSL) Committee's Opioid Working Group. It is a systematic review of existing literature for various interventions related to the preoperative and intraoperative pain management of cardiac surgical patients. This Practice Advisory provides recommendations for providers caring for patients undergoing cardiac surgery. This entails developing customized pain management strategies for patients, including preoperative patient evaluation, pain management, and opioid use-focused education as well as perioperative use of multimodal analgesics and regional techniques for various cardiac surgical procedures. The literature related to this field is emerging, and future studies will provide additional guidance on ways to improve clinically meaningful patient outcomes.

Analgesic efficacy and risk of low-to-medium dose intrathecal morphine in patients undergoing cardiac surgery: An updated meta-analysis

Background

To evaluate the analgesic efficacy and risk of low-to-medium dose intrathecal morphine (ITM) (i.e., ≤0.5 mg) following cardiac surgery.

Methods

Medline, Cochrane Library, Google scholar and EMBASE databases were searched from inception to February 2022. The primary outcome was pain intensity at postoperative 24 h, while the secondary outcomes included intravenous morphine consumption (IMC), extubation time, hospital/intensive care unit (ICU) length of stay (LOS), and ITM-associated side effects (e.g., respiratory depression). Subgroup analysis was performed on ITM dosage (low: <0.3 mg vs. medium: 0.3–0.5 mg).

Results

Fifteen RCTs involving 683 patients published from 1988 to 2021 were included. Pooled results showed significantly lower postoperative 24-h pain scores [mean difference (MD) = −1.61, 95% confidence interval: −1.98 to −1.24, p < 0.00001; trial sequential analysis: sufficient evidence; certainty of evidence: moderate] in the ITM group compared to the controls. Similar positive findings were noted at 12 (MD = −2.1) and 48 h (MD = −1.88). Use of ITM was also associated with lower IMC at 24 and 48 h (MD: −13.69 and −14.57 mg, respectively; all p < 0.05) and early tracheal extubation (i.e., 48.08 min). No difference was noted in hospital/ICU LOS, and nausea/vomiting in both groups, but patients receiving ITM had higher risk of pruritus (relative risk = 2.88, p = 0.008). There was no subgroup difference in IMC except a lower pain score with 0.3–0.5 mg than <0.3 mg at postoperative 24 h. Respiratory depression events were not noted in the ITM group.

Conclusion

Our results validated the analgesic efficacy of low-to-medium dose ITM for patients receiving cardiac surgery without increasing the risk of respiratory depression.

Year in Review 2021: Noteworthy Literature in Cardiothoracic Anesthesia

In 2021, progress in clinical science related to Cardiac Anesthesiology continued, but at a slower rate due to the ongoing pandemic and disruptions to clinical research. Most progress was incremental and addressed persistent questions related to our field. To identify articles for this review, we completed a structured review using our previously reported methods (1). Specifically, we used the search terms: "cardiac anesthesiology and outcomes" (n = 177), "cardiothoracic anesthesiology" (n = 34), "cardiac anesthesia," and "clinical outcomes" (n = 42) filtered on clinical trials and the year 2021 in PubMed. We also reviewed clinical trials from the most prominent clinical journals to identify additional studies for a narrative review. We then selected the most noteworthy publications for inclusion in this review and identified key themes.

Current Status of Neuraxial and Paravertebral Blocks for Adult Cardiac Surgery

Cardiac surgeries are known to produce moderate to severe pain. Pain management has traditionally been based on intravenous opioids. Poorly controlled pain can result in increased incidence of respiratory complications such as atelectasis and pneumonia leading to prolonged intubation and intensive care unit length of stay and subsequent prolonged hospital stay. Adequate perioperative analgesia improves hemodynamics and immunologic responses, which would result in better outcomes after cardiac surgery. Opioid sparing "Enhanced Recovery After Surgery" protocols are increasingly being incorporated into cardiac surgeries. This will reduce opioid requirements and opioid-related side effects and facilitate fast-tracking of patients. Regional analgesia can be provided by neuraxial blocks, fascial plane blocks, peripheral nerve blocks, or simply by the infiltration of the wound with local anesthetics for cardiac surgery. Neuraxial analgesia is provided through epidural, spinal, and paravertebral routes. Though they are being replaced by peripheral fascial plane blocks, epidural and spinal analgesia are still being used in some centers. In this article, neuraxial forms of analgesia are focused. We sought to review epidural analgesia and its impact in suppressing hemodynamic stress response, reducing pulmonary complications, and development of chronic pain. The relationship between intraoperative heparinization and potential neuraxial hematoma is discussed. Other neuraxial options such as spinal and paravertebral analgesia and their usefulness, benefits, and limitations are also reviewed.

Postoperative hemodynamics after high spinal block with or without intrathecal morphine in cardiac surgical patients: a randomized-controlled trial

PURPOSE

There is some evidence for the use of intrathecal morphine as a means to provide prolonged analgesia in selective cardiac surgical patients; however, the hemodynamic effects of intrathecal morphine are not well defined. This study was designed to study the effect of intrathecal morphine on hemodynamic parameters in cardiac surgery patients.

METHODS

In a prospective, double-blind study, 100 adult cardiac surgical patients were randomized to receive either intrathecal 40 mg of 0.5% hyperbaric bupivacaine alone (intrathecal bupivacaine [ITB] group, n = 50) or intrathecal 250 µg of morphine added to 40 mg of 0.5% bupivacaine (intrathecal bupivacaine and morphine [ITBM] group, n = 50). Hemodynamic data, pain scores, rescue analgesic use, spirometry, and vasopressor use were recorded every four hours after surgery for 48 hr. The primary outcome was the incidence of vasoplegia in each group, which was defined as a cardiac index > 2.2 L·min-1·m-2 with the requirement of vasopressors to maintain the mean arterial pressure > 60 mmHg with the hemodynamic episode lasting > four hours.

RESULTS

Eighty-seven patients were analyzed (ITB group, n = 42, and ITBM group, n =45). The incidence of vasoplegia was higher in the ITBM group than in the ITB group [14 (31%) vs 5 (12%), respectively; relative risk, 2.6; 95% confidence interval [CI], 1.0 to 6.6; P = 0.04]. The mean (standard deviation [SD]) duration of vasoplegia was significantly longer in the ITBM group than in the ITB group [8.9 (3.0) hr vs 4.3 (0.4) hr, respectively; difference in means, 4.6; 95% CI, 3.7 to 5.5; P < 0.001].

CONCLUSION

Intrathecal morphine added to bupivacaine for high spinal anesthesia increases the incidence and duration of vasoplegia in cardiac surgery patients.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT02825056); registered 19 June 2016.

The Impact of Anesthetic Regimen on Outcomes in Adult Cardiac Surgery: A Narrative Review

Despite improvements in surgical techniques and perioperative care, cardiac surgery still is burdened by relatively high mortality and frequent major postoperative complications, including myocardial dysfunction, pulmonary complications, neurologic injury, and acute kidney injury. Although the surgeon's skills and volume and patient- and procedure-related risk factors play a major role in the success of cardiac surgery, there is growing evidence that also optimizing perioperative care may improve outcomes significantly. The present review focuses on the aspects of perioperative care that are strictly related to the anesthesia regimen, with special reference to volatile anesthetics and neuraxial anesthesia, whose effect on outcome in adult cardiac surgery has been investigated extensively.

Pretreatment with glucose-insulin-potassium improves ventricular performances after coronary artery bypass surgery: a randomized controlled trial

Heart failure is the main cause of poor outcome following open heart surgery and experimental studies have demonstrated that glucose–insulin–potassium (GIK) infusion exerts cardioprotective effects by reducing myocardial ischemia–reperfusion injuries. This randomized controlled trial was designed to assess the effects of GIK on left ventricular function in moderate-to-high risk patients undergoing on-pump isolated coronary artery bypass surgery (CABGS), or combined with aortic valve replacement. The primary outcomes were the effects of GIK on two- and three-dimensional left ventricular ejection fraction (2D and 3D-LVEF), and on transmitral flow propagation velocity (Vp), that occurred between the pre- and post-CPB periods. GIK administration was associated with favorable interaction effects (p < 0.001) on 2D-LVEF, 3D-LVEF and Vp changes over the study periods. In GIK pretreated patients (N = 54), 2-D and 3D-LVEF and Vp increased slightly during surgery (mean difference [MD] + 3.5%, 95% confidence interval [95% CI] − 0.2 to 7.1%, MD + 4.0%, 95% CI 0.6–7.4%, and MD + 22.2%, 95% CI 16.0–28.4%, respectively). In contrast, in the Placebo group (N = 46), 2D-and 3D-LVEF, as well as Vp all decreased after CPB (MD − 7.5% [− 11.6 to − 3.4%], MD − 12.0% [− 15.2 to − 8.8%] and MD − 21.3% [− 25.7 to − 16.9%], respectively). In conclusion, the administration of GIK resulted in better preservation of systolic and diastolic ventricular function in the early period following weaning from CPB.