Combination of Intrathecal Morphine and Remifentanil Infusion for Fast-Track Anesthesia in Off-Pump Coronary Artery Bypass Surgery

Non-pulmonary complications of intrathecal morphine administration: a systematic review and meta-analysis with meta-regression

BACKGROUND

Intrathecal morphine provides effective analgesia for a range of operations. However, widespread implementation into clinical practice is hampered by concerns for potential side-effects. We undertook a systematic review, meta-analysis, and meta-regression with the primary objective of determining whether a threshold dose for non-pulmonary complications could be defined and whether an association could be established between dose and complication rates when intrathecal morphine is administered for perioperative or obstetric analgesia.

METHODS

We systematically searched the literature for randomised controlled trials comparing intrathecal morphine vs control in patients undergoing any type of surgery under general or spinal anaesthesia, or women in labour. Primary outcomes were rates of postoperative nausea and vomiting, pruritus, and urinary retention within the first 24 postoperative hours, analysed according to doses (1-100 μg; 101-200 μg; 201-500 μg; >500 μg), type of surgery, and anaesthetic strategy. Trials were excluded if doses were not specified.

RESULTS

Our analysis included 168 trials with 9917 patients. The rates of postoperative nausea and vomiting, pruritus, and urinary retention were significantly increased in the intrathecal morphine group, with an odds ratio (95% confidence interval) of 1.52 (1.29-1.79), P<0.0001; 6.11 (5.25-7.10), P<0.0001; and 1.73 (1.17-2.56), P=0.005, respectively. Meta-regression could not establish an association between dose and rates of non-pulmonary complications. There was no subgroup difference according to surgery for any outcome. The quality of evidence was low (Grading of Recommendations Assessment, Development, and Evaluation [GRADE] system).

CONCLUSIONS

Intrathecal morphine significantly increased postoperative nausea and vomiting, pruritus, and urinary retention after surgery or labour in a dose-independent manner.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42023387838).

Pain management after cardiac surgery via median sternotomy: A systematic review with procedure-specific postoperative pain management (PROSPECT) recommendations

BACKGROUND

Pain after cardiac surgery via median sternotomy can be difficult to treat, and if inadequately managed can lead to respiratory complications, prolonged hospital stays and chronic pain.

OBJECTIVES

To evaluate available literature and develop recommendations for optimal pain management after cardiac surgery via median sternotomy.

DESIGN

A systematic review using PROcedure-SPECific Pain Management (PROSPECT) methodology.

ELIGIBILITY CRITERIA

Randomised controlled trials and systematic reviews published in the English language until November 2020 assessing postoperative pain after cardiac surgery via median sternotomy using analgesic, anaesthetic or surgical interventions.

DATA SOURCES

PubMed, Embase and Cochrane Databases.

RESULTS

Of 319 eligible studies, 209 randomised controlled trials and three systematic reviews were included in the final analysis. Pre-operative, intra-operative and postoperative interventions that reduced postoperative pain included paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), intravenous magnesium, intravenous dexmedetomidine and parasternal block/infiltration.

CONCLUSIONS

The analgesic regimen for cardiac surgery via sternotomy should include paracetamol and NSAIDs, unless contraindicated, administered intra-operatively and continued postoperatively. Intra-operative magnesium and dexmedetomidine infusions may be considered as adjuncts particularly when basic analgesics are not administered. It is not clear if combining dexmedetomidine and magnesium would provide superior pain relief compared with either drug alone. Parasternal block/surgical site infiltration is also recommended. However, no basic analgesics were used in the studies assessing these interventions. Opioids should be reserved for rescue analgesia. Other interventions, including cyclo-oxygenase-2 specific inhibitors, are not recommended because there was insufficient, inconsistent or no evidence to support their use and/or due to safety concerns.

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.

Impact of high spinal anesthesia technique on fast-track strategy in cardiac surgery: retrospective study

BACKGROUND AND OBJECTIVES

Although high spinal anesthesia (HSA) has been used in cardiac surgery, the technique has not yet been widely accepted. This retrospective study was designed to investigate the impact of HSA technique on fast-track strategy in cardiac surgery.

METHODS

Elective cardiac surgery cases (n=1025) were divided into two groups: cases with HSA combined with general anesthesia (GA) (HSA group, n=188) and cases with GA only (GA group, n=837). In the HSA group, bupivacaine and morphine were intrathecally administered immediately before GA was induced. Outcomes included fast-track extubation (less than 6 hours), extubation in the operating room, fast-track discharge from the intensive care unit (ICU) (less than 48 hours) and hospital (less than 7 days).

RESULTS

In the HSA group, 60.1% were extubated in less than 6 hours after ICU admission, as compared with 39.9% in the GA group (p<0.001). In the HSA group, 33.0% were extubated in the operating room, as compared with 4.4% in the GA group (p<0.001). LOS in the ICU was less than 48 hours in 67.6% in the HSA group, as compared with 57.2% of those in the GA group (p=0.033). LOS in the hospital was less than 7 days in 63.3% in the HSA group, as compared with 53.5% in the GA group (p=0.084).

CONCLUSIONS

HSA technique combined with GA in cardiac surgery increased the rate of fast-track extubation (less than 6 hours) when compared with GA only.

Effectiveness of combined regional-general anesthesia for reducing mortality in coronary artery bypass: meta-analysis

BACKGROUND AND OBJECTIVES

Neuraxial anesthesia (NA) has been used in association with general anesthesia (GA) for coronary artery bypass; however, anticoagulation during surgery makes us question the viability of benefits by the risk of epidural hematoma. The aim of this study was to perform a meta-analyzes examining the efficacy of NA associated with GA compared to GA alone for coronary artery bypass on mortality reduction.

METHODS

Mortality, arrhythmias, cerebrovascular accident (CVA), myocardial infarction (MI), length of hospital stay (LHS), length of ICU stay (ICUS), reoperations, blood transfusion (BT), quality of life, satisfaction degree, and postoperative cognitive dysfunction were analyzed. The weighted mean difference (MD) was estimated for continuous variables, and relative risk (RR) and risk difference (RD) for categorical variables.

RESULTS

17 original articles analyzed. Meta-analysis of mortality (RD=-0.01, 95% CI=-0.03 to 0.01), CVA (RR=0.79, 95% CI=0.32-1.95), MI (RR=0.96, 95% CI=0.52-1.79) and LHS (MD=-1.94, 95% CI=-3.99 to 0.12) were not statistically significant. Arrhythmia was less frequent with NA (RR=0.68, 95% CI=0.50-0.93). ICUS was lower in NA (MD=-2.09, 95% CI=-2.92 to -1.26).

CONCLUSION

There was no significant difference in mortality. Combined NA and GA showed lower incidence of arrhythmias and lower ICUS.

A clinical approach to neuraxial morphine for the treatment of postoperative pain

Opioids are considered a “gold standard” in clinical practice for the treatment of postoperative pain. The spinal administration of an opioid drug does not guarantee selective action and segmental analgesia in the spine. Evidence from experimental studies in animals indicates that bioavailability in the spinal cord biophase is negatively correlated with liposolubility, and is higher for hydrophilic opioids, such as morphine, than lipophilic opioids, such as fentanyl, sufentanil and alfentanil. Epidural morphine sulphate has proven analgesic efficacy and superiority over systemically administered morphine for improving postoperative pain. However, pain relief after a single epidural injection of morphine could last less than 24 hours. Techniques used to administered and prolong opioid epidural analgesia, can be costly and inconvenient. Moreover, complications can arise from indwelling epidural catheterization, particularly in patients receiving anticoagulants. Clinical trials have shown that epidural morphine in the form of extended-release liposome injections (EREM) gives good analgesia for a period of 48 hours, with no need for epidural catheterisation. Intrathecal morphine produces intense analgesia for up to 24 hours with a single shot, and clinical recommendation is to choose the minimum effective dose and do not exceed 300 μg to prevent the delay respiratory depression.

Benefit and risk of intrathecal morphine without local anaesthetic in patients undergoing major surgery: meta-analysis of randomized trials

Intrathecal morphine without local anaesthetic is often added to a general anaesthetic to prevent pain after major surgery. Quantification of benefit and harm and assessment of dose-response are needed. We performed a meta-analysis of randomized trials testing intrathecal morphine alone (without local anaesthetic) in adults undergoing major surgery under general anaesthesia. Twenty-seven studies (15 cardiac-thoracic, nine abdominal, and three spine surgery) were included; 645 patients received intrathecal morphine (dose-range, 100-4000 microg). Pain intensity at rest was decreased by 2 cm on the 10 cm visual analogue scale up to 4 h after operation and by about 1 cm at 12 and 24 h. Pain intensity on movement was decreased by 2 cm at 12 and 24 h. Opioid requirement was decreased intraoperatively, and up to 48 h after operation. Morphine-sparing at 24 h was significantly greater after abdominal surgery {weighted mean difference, -24.2 mg [95% confidence interval (CI) -29.5 to -19.0]}, compared with cardiac-thoracic surgery [-9.7 mg (95% CI -17.6 to -1.80)]. The incidence of respiratory depression was increased with intrathecal morphine [odds ratio (OR) 7.86 (95% CI 1.54-40.3)], as was the incidence of pruritus [OR 3.85 (95% CI 2.40-6.15)]. There was no evidence of linear dose-responsiveness for any of the beneficial or harmful outcomes. In conclusion, intrathecal morphine decreases pain intensity at rest and on movement up to 24 h after major surgery. Morphine-sparing is more pronounced after abdominal than after cardiac-thoracic surgery. Respiratory depression remains a major safety concern.

Prise en charge anesthésique de l'œsophagectomie: avancées et perspectives

Oesophagectomy is still characterized by a high postoperative mortality and respiratory morbidity. Nevertheless, epidemiological, medical and surgical advances have improved the management of this surgical procedure. The anaesthesiologist influence is present at each level, from the preoperative evaluation to the management of postoperative complications. The preoperative period is improved by the use of assessment scores, the better knowing of respiratory risk factors and of the neoadjuvant therapy adverse effects. The main objective of the operative period is to ensure a rapid weaning procedure and stability of the respiratory and haemodynamic functions, warranting the anastomotic healing. The interest of the association between respiratory rehabilitation and thoracic epidural analgesia is highlighted in the postoperative period. The management of postoperative complications, mainly represented by respiratory failure and anastomotic leakages, requires a multidisciplinary analysis. The potential interest of non-invasive ventilation and of the modulation of postoperative inflammatory response needs further investigation.

Endogenous opiates and behavior: 2005

This paper is the 28th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over a quarter-century of research. It summarizes papers published during 2005 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity, neurophysiology and transmitter release (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); immunological responses (Section 17).