Laurence Roediger

New approaches and old controversies to postoperative pain control following cardiac surgery

Objective: To evaluate the effect of postoperative pain control in cardiac surgical patients on morbidity, mortality and other outcome measures. Background: New approaches in pain control have been introduced over the past decade. The impact of these interventions, either alone or in combination, on perioperative outcome was evaluated in cardiac surgical patients. Methods: We searched Medline for the period of 1980 to the present using the key terms analgesics, opioid, non‐steroidal anti‐inflammatory drugs, cardiac surgery, regional analgesia, spinal, epidural, fast‐track cardiac anaesthesia, fast‐track cardiac surgery, myocardial ischaemia, myocardial infarction, postoperative care, accelerated care programmes, postoperative complications, and we examined and discussed the articles that were identified to be included in this review. Results: Pain management in cardiac surgery is becoming more important with the establishment of minimally invasive direct coronary artery bypass surgery and fast‐track management of conventional cardiac surgery patients. Advances have been made in this area and encompass specific techniques, such as central neuraxial blockade or selective nerve blocks, and drugs (opioids, sedative‐hypnotics and non‐steroidal anti‐inflammatory drugs). Ideally, these therapies provide not only patient comfort but also mitigate untoward cardiovascular responses, pulmonary responses, and other inflammatory and secondary sympathetic responses. The introduction of these newer approaches to perioperative care has reduced morbidity, but not mortality, in cardiac surgical patients. Conclusions: Understanding perioperative pathophysiology and implementation of care regimes to reduce the stress of cardiac surgery, will continue to accelerate rehabilitation associated with decreased hospitalization and increased satisfaction and safety after discharge. Reorganization of the perioperative team (anaesthesiologists, surgeons, nurses and physical therapists) will be essential to achieve successful fast‐track cardiac surgical programmes. Developments and improvements of multimodal interventions within the context of ‘fast‐track’ cardiac surgery programmes represents the major challenge for the medical professionals working to achieve a ‘pain and risk free’ perioperative course.

Effect of celecoxib combined with thoracic epidural analgesia on pain after thoracotomy

BACKGROUND Thoracotomy results in severe postoperative pain potentially leading to chronic pain. We investigated the potential benefits of oral celecoxib on postoperative analgesia combined with thoracic epidural analgesia (TEA). METHODS Forty patients undergoing thoracotomy were included in this prospective, randomized, double-blind, placebo-controlled study. General anaesthesia was standardized. Patient-controlled epidural analgesia (T4-T5) was used during 48 h after surgery (ropivacaine 2 mg ml(-1) with sufentanil 0.5 microg ml(-1)). Patients were allocated to receive oral celecoxib or placebo from the evening before surgery until 48 h after operation. Postoperative pain scores, respiratory function, and morbidity were compared between the two groups. RESULTS Postoperative pain scores at rest (P=0.026) and during coughing (P=0.021) were lower and patient satisfaction was greater (P=0.0033) in the celecoxib group. Consumption of the local anaesthetic solution was comparable between groups. Postoperative restrictive pulmonary syndrome and morbidity were comparable between groups. CONCLUSIONS Celecoxib improves postoperative analgesia provided by TEA after thoracotomy.

The use of pre‐operative intrathecal morphine for analgesia following coronary artery bypass surgery

With the emergence of rapid extubation protocols following cardiac surgery, providing adequate analgesia in the early postoperative period is important. This prospective randomised double‐blind study investigated the benefits of pre‐operative intrathecal administration of low dose morphine in patients undergoing coronary artery bypass graft surgery. Postoperative analgesia, pulmonary function, stress response and postoperative recovery profile were assessed. Thirty patients were allocated into two groups, receiving either 500 μg of morphine intrathecally prior to anaesthesia and intravenous patient‐controlled analgesia with morphine postoperatively following tracheal extubation, or only postoperative intravenous patient‐controlled analgesia. In the intrathecal group, the total consumption of intravenous morphine following surgery was significantly reduced by 40% and patients reported lower pain scores at rest, during the first 24 h following extubation. Peak expiratory flow rate was greater and postoperative catecholamine release was significantly lower. Patients in the control group had a higher incidence of reduced respiratory rate following extubation.

The effect of intraoperative 6% balanced hydroxyethyl starch (130/0.4) during cardiac surgery on transfusion requirements.

OBJECTIVES To compare transfusion requirements in adult cardiac surgery patients when balanced hydroxyethyl starches (HES) (130/0.4) or balanced crystalloids is used for pump prime and intraoperative fluid therapy. DESIGN Data were obtained retrospectively from medical records and perfusion charts. Matching based on propensity scores was used to adjust for potential confounders. SETTING A university hospital. PARTICIPANTS Adult patients undergoing cardiac surgery with the use of cardiopulmonary bypass. INTERVENTIONS Allocation to one of the study groups according to whether balanced HES or balanced crystalloids was used for pump prime and intraoperative fluid therapy. MEASUREMENTS AND MAIN RESULTS 240 propensity-matched patients were retained for final analyses. Forty-eight patients (40%) of the colloid group and 28 patients (23.3%) of the crystalloid group received blood products, with an odd ratio (95% CI) of 2.1(1.2-3.8 (P=0.009). After bypass HES patients had lower hemoglobin levels (8.4 [1.3] gr/dL vs 9.6 [2] gr/dL; P<0.001) and a higher cumulative chest drain output after 3 hours (180 [210] mL vs 140 [100] mL, P<0.001]. Heparinase thromboelastogram (TEG®) showed longer K times (2.5[1.1] vs 1.6[0.8], P<0.001) and lower maximal amplitudes (55.1[12.5] vs 63.4[9.8], P=0.008). CONCLUSIONS HES patients required more transfusions, owing to greater hemodilution, HES-induced clotting disturbances, and bleeding.

Hydroxyethyl Starch 130/0.4 and the Risk of Acute Kidney Injury After Cardiopulmonary Bypass: A Single-Center Retrospective Study

OBJECTIVES To investigate whether using hydroxyethyl starch (HES) 130/0.4 as a pump prime and for intraoperative fluid therapy is associated with postoperative acute kidney injury (AKI) after adult cardiac surgery. DESIGN Retrospective observational study. SETTING University hospital, single center. PARTICIPANTS Six hundred six adult patients who underwent on-pump cardiac surgery between April 2013 and June 2014 were included. INTERVENTIONS Until July 2013, balanced HES 130/0.4 (Volulyte(®), Fresenius Kabi AG, Bad Homburg, Germany) was used both as a pump prime (1,500 mL) and for intraoperative fluid therapy (1,000 mL). From August 2013, HES was replaced entirely by a balanced crystalloid solution (Plasma-Lyte A, Baxter, Lessines, Belgium). MEASUREMENTS AND MAIN RESULTS The primary endpoint was the incidence of postoperative AKI during the first 48 postoperative hours, determined using the Acute Kidney Injury Network classification. Secondary outcomes included kidney function at postoperative day 7, postoperative dialysis or hemofiltration, postoperative pulmonary complications, lengths of intensive care unit and hospital stays, postoperative fluid balance and urinary output, surgical revision for bleeding, and 30-day mortality. Multivariable logistic regression was used to adjust for confounders. AKI occurred in 9.5% of crystalloid patients and in 21.5% of HES patients. Patients who received HES were about twice as likely to develop postoperative AKI as those treated with crystalloids (adjusted OR 2.26; 95% CI, 1.40-3.80; p = 0.02). HES patients also had a significantly more positive fluid balance and a lower urinary output during the first 48 postoperative hours. The incidence of surgical revision for bleeding was greater in the HES group (4.6% v 1.4%, p = 0.02). CONCLUSION This study suggested that using balanced HES 130/0.4 as a pump prime and for intraoperative fluid therapy in adult patients undergoing on-pump cardiac surgery was associated with a greater incidence of AKI during the early postoperative period.

Impact of 6 % hydroxyethyl starch (HES) 130/0.4 on the correlation between standard laboratory tests and thromboelastography (TEG®) after cardiopulmonary bypass

BACKGROUND Hydroxyethyl starches (HES) affect the results of thromboelastography (TEG®). We sought to determine whether using HES rather than crystalloids for cardiopulmonary bypass (CPB) prime and intraoperative fluid therapy changes the TEG cutoff values best identifying patients with a low platelet count or a low fibrinogen level after CPB. METHODS Data from 96 patients who had on-pump cardiac surgery, a TEG® (kaolin-heparinase) and standard investigations of blood clotting performed after separation from CPB and protamine administration were retrospectively reviewed. Patients were assigned to the HES or crystalloid group according to whether balanced 6% HES 130/0.4 or balanced crystalloids were used for intraoperative fluid therapy and pump prime. Mutlivariable linear regression models with computation of the standardized regression coefficients were used to identify independent associations between the four main TEG parameters (R time, alpha angle, K time and MA) and the type of fluid used, the INR, the aPTT, the fibrinogen level and the platelet count. Receiver-operating-characteristic curves were used to assess the effect of HES on the ability of TEG parameters to identify patients with a platelet count<80.000μl(-1) or a fibrinogen level<1.5 gr l(-1) and on the cutoff values best identifying these patients. RESULTS The type of fluid used significantly affected the MA (P<0.001), the K time (P<0.001) and the alpha angle (P<0.001) regardless of the results of the standard clotting tests. According to standardized ß regression coefficients the platelet count and the type of fluid used were stronger predictors of the MA, the alpha angle and the K time than the fibrinogen level. MA better predicted platelets<80.000μl(-1) than K time and alpha angle (P=0.023). The best cutoff value of MA identifying patients with platelets<80.000μl(-1) was 62mm in the crystalloid group and 53mm in the HES group. MA, K time and alpha angle were poor predictors of the postoperative fibrinogen level. CONCLUSION HES significantly changes the cutoff value of TEG® MA best identifying patients<80.000μl(-1) after on-pump cardiac surgery.

Efficacy of the RemoweLL cardiotomy reservoir for fat and leucocyte removal from shed mediastinal blood: a randomized controlled trial.

Introduction: Re-transfusion of lipid particles and activated leucocytes with shed mediastinal blood (SMB) can aggravate cardiopulmonary bypass-associated inflammation and increase the embolic load. This study evaluated the fat and leucocyte removal capacity of the RemoweLL cardiotomy reservoir. Methods: Forty-five patients undergoing elective on-pump cardiac surgery were randomly allocated to filtration of SMB using the RemoweLL or the Admiral cardiotomy reservoir. The primary outcome was a drop in leucocytes and lipid particles obtained with the two filters. The effect of the filters on other blood cells and inflammatory mediators, such as myeloperoxidase (MPO), was also assessed. Results: The RemoweLL cardiotomy filter removed 16.5% of the leucocytes (p<0.001) while no significant removal of leucocytes was observed with the Admiral (p=0.48). The percentage reductions in lipid particles were similar in the two groups (26% vs 23%, p=0.2). Both filters similarly affected the level of MPO (p=0.71). Conclusion: The RemoweLL filter more effectively removed leucocytes from SMB than the Admiral. It offered no advantage in terms of lipid particle clearance.

The Edmonton Frail Scale Improves the Prediction of 30-Day Mortality in Elderly Patients Undergoing Cardiac Surgery: A Prospective Observational Study

OBJECTIVES To investigate whether the Edmonton Frail Scale (EFS), a multidimensional frailty assessment tool, improves the prediction of 30-day or in-hospital mortality over the use of the European System for Cardiac Outcome Risk Evaluation (EuroSCORE) II alone. DESIGN Single-center prospective observational study. SETTING University hospital. PARTICIPANTS Patients aged 75 years or older undergoing cardiac surgery between February 2014 and May 2017. INTERVENTION No intervention was performed. The EFS was administered the day before surgery. MEASUREMENTS AND MAIN RESULTS The primary endpoint was 30-day or in-hospital mortality. Secondary endpoints were times to discharge from the intensive care unit (ICU) and from the hospital, discharge to a health care facility, and ability to return home by postoperative day 30. The EFS had a good discriminative ability for 30-day mortality (area under the receiver operating characteristic curve = 0.69; 95% confidence interval [CI], 0.56-0.82). Adding frailty, defined by an EFS ≥8, to the EuroSCORE II significantly improved the prediction of 30-day (p = 0.04) mortality. The integrated discrimination index was 0.03 (95% CI, 0.01-0.06, p = 0.01), meaning that the difference in predicted risk between patients who died and those who survived increased by 3% due to the addition of frailty determined by the EFS to the EuroSCORE II. Frailty also was associated significantly with a decreased cumulative probability of discharge from the ICU (p = 0.02) and an increased incidence of discharge to a health care facility (p = 0.01). CONCLUSION The EFS has a good predictive ability for 30-day mortality after cardiac surgery in elderly patients and improves the prediction of 30-day mortality over the use of the EuroSCORE II.

Effects of perioperative i.v. infusion of low dose ketamine associated with thoracic epidural analgesia for abdominal aortic surgery on postoperative analgesia and early postoperative outcome: 14AP1-3

Anaesthesia and Intensive Care, University Hospital, Liège, Belgium Background and Goal of Study: Thoracic epidural analgesia (TEA) provides effective analgesia and improves outcome after abdominal surgery (1). Some peritoneal nociceptive inputs are not blocked by TEA (2). Ketamine (K.) prevents postop. hyperalgesia through central and peripheral mechanisms (3). We investigated effects of the adjunction of perioperative iv K. to TEA, on early postop. analgesia and outcome after open abdominal aortic surgery (AAS). Materials and Methods: After approval of ethic committee and informed consent, 36 patients scheduled for open AAS were included in this study. Combined general anaesthesia with TEA were used in all patients. TEA (T9–T10) was started before surgical incision and maintained for the first 60 h postop (ropivacaine 0.2% 0.5 g/ml sufentanil). After induction of anaesthesia, patients were randomly allocated in two groups (n 18 in each group): patients were given an iv bolus of K. (225 g/kg) followed by an infusion (100 g/kg/h) during the first 24 h postop (K) or same volume of saline (S). All patients were provided with a piritramide PCA pump for 96 h. Pain scores (VAS), piritramide consumption, respiratory function, postop outcome (PONV, satisfaction, fatigue, time to first flatus, ambulation, hospital stay, stress response, and morbidity) were recorded. ANOVA for repeated measures, Student’s t, Mann-Whitney and Fischer exact test were used with p 0.05 as significant. Results and Discussions: Demographic data, pain scores at rest (p 0.1), coughing (p 0.2) and mobilization (p 0.24) and piritramide consumption (p 0.56) (table) were not significantly different between the groups.