The effect of continuous bilateral parasternal block with lidocaine on patient-controlled analgesia opioid requirement and recovery after open heart surgery: a double-blind randomised controlled trial.

Background: We hypothesised that a continuous 72-h bilateral parasternal infusion of lidocaine at 2×35 mg h-1 would decrease pain and the inflammatory response after sternotomy for open heart surgery, subsequently improving quality of recovery. Methods: We randomly allocated 45 participants to a 72-h bilateral parasternal infusion of lidocaine or saline commencing after wound closure. The primary outcome was the cumulative patient-controlled analgesia (PCA) morphine consumption at 72 h. Secondary outcomes included total morphine requirement, pain, peak expiratory flow, and serum interleukin-6 concentration. In addition, we used an eHealth platform for a 3-month follow-up of pain, analgesic use, and Quality of Recovery-15 scores. Results: The 72-h PCA morphine requirement was significantly lower in the lidocaine than the saline group (10 mg [inter-quartile range: 5-19 mg] and 28.2 mg [inter-quartile range: 16-42.5 mg], respectively; P=0.014). The total morphine requirement (including morphine administered before the start of PCA) was significantly lower at 24, 48, and 72 h. Pain was well controlled with no difference in pain scores between treatment groups. The peak expiratory flow was lower in the lidocaine group at 72 h. Interleukin-6 concentrations showed no difference at 24, 48, or 72 h. Quality of Recovery-15 scores did not differ between treatment groups at any time during the 3-month follow-up. Conclusions: After sternotomy for open heart surgery, a 72-h bilateral parasternal lidocaine infusion significantly decreased PCA and total morphine requirement. However, neither signs of decreased inflammatory response nor an improvement in recovery was seen. Clinical trial registration: EudraCT number 2018-004672-35.

Extrapleural infusion of levobupivacaine versus levobupivacaine-sufentanil-adrenaline after video-assisted thoracoscopic surgery (VATS): A randomised controlled trial.

BACKGROUND: Peripheral blocks are increasingly used for analgesia after video-assisted thoracic surgery (VATS). We hypothesised that addition of sufentanil and adrenaline to levobupivacaine would improve the analgesic effect of a continuous extrapleural block. METHODS: We randomised 60 patients undergoing VATS to a 5-mL h-1 extrapleural infusion of levobupivacaine at 2.7 mg mL-1 (LB group) or levobupivacaine at 1.25 mg mL-1 , sufentanil at 0.5 µg mL-1 , and adrenaline at 2 µg mL-1 (LBSA group). The primary outcome was the cumulative morphine dose administered as patient-controlled analgesia (PCA-morphine) at 48 and 72 h. The secondary outcomes were pain according to numerical rating scale (NRS) at rest and after two deep breaths twice daily, peak expiratory flow (PEF) daily, quality of recovery (QoR)-15 score at 1 day and 3 weeks postoperatively, serum levobupivacaine concentrations at 1 h after the start and at the end of the intervention, and adverse events. RESULTS: At 48 h, the median cumulative PCA-morphine dose for the LB group was 6 mg (IQR, 2-10 mg) and for the LBSA group 7 mg (IQR, 3-13.5 mg; p = .378). At 72 h, morphine doses were 10 mg (IQR, 3-22 mg) and 12.5 mg (IQR, 4-21 mg; p = .738), respectively. Median NRS score at rest and after two deep breaths was 3 or lower at all time points for both treatment groups. PEF did not differ between groups. Three weeks postoperatively, only the LB group returned to baseline QoR-15 score. The LB group had higher, but well below toxic, levobupivacaine concentrations at 48 and 72 h. The incidence of nausea, dizziness, pruritus and headache was equally low overall. CONCLUSION: For a continuous extrapleural block, and compared to plain levobupivacaine at 13.5 mg h-1 , levobupivacaine at 6.25 mg h-1 with addition of sufentanil and adrenaline did not decrease postoperative morphine consumption. The levobupivacaine serum concentrations after 48 and 72 h of infusion were well below toxic levels, therefore our findings support the use of the maximally recommended dose of levobupivacaine for a 2- to 3-day continuous extrapleural block.

Parasternal After Cardiac Surgery (PACS): a prospective, randomised, double-blinded, placebo-controlled trial study protocol for evaluating a continuous bilateral parasternal block with lidocaine after open cardiac surgery through sternotomy.

BACKGROUND: Multimodal analgesia that provides optimal pain treatment with minimal side effects is important for optimal recovery after open cardiac surgery. Regional anaesthesia can be used to block noxious nerve signals. Because sternotomy causes considerable pain that lasts several days, a continuous nerve block is advantageous. Previous studies on continuous sternal wound infusion or parasternal blocks with long-acting local anaesthetics have shown mixed results. This study aims to determine whether a continuous bilateral parasternal block with lidocaine, which is a short-acting local anaesthetic that has a favourable safety/toxicity profile, results in effective analgesia. We hypothesise that a 72-hour continuous parasternal block with 0.5% lidocaine at a rate of 7 ml/hour on each side provides effective analgesia and reduces opioid requirement. We will evaluate whether recovery is enhanced. METHODS: In a prospective, randomised, double-blinded manner, 45 patients will receive a continuous parasternal block with either 0.5% lidocaine or saline. The primary endpoint is cumulated intravenous morphine by patient-controlled analgesia at 72 hours. Secondary end-points include the following: (1) the cumulated numerical rating scale (NRS) score recorded three times daily at 72 hours; (2) the cumulated NRS score after two deep breaths three times daily at 72 hours; (3) the NRS score at rest and after two deep breaths at 2, 4, 8 and 12 weeks after surgery; (4) oxycodone requirement at 2, 4, 8 and 12 weeks after surgery; (5) Quality of Recovery-15 score preoperatively compared with that at 24, 48 and 72 hours, and at 2, 4, 8 and 12 weeks after surgery; (6) preoperative peak expiratory flow compared with postoperative daily values for 3 days; and (7) serum concentrations of interleukin-6 and lidocaine at 1, 24, 48 and 72 hours postoperatively compared with preoperative values. DISCUSSION: Adequate analgesia is important for quality of care and vital to a rapid recovery after cardiac surgery. This study aims to determine whether a continuous parasternal block with a short-acting local anaesthetic improves analgesia and recovery after open cardiac procedures. TRIAL REGISTRATION: The study was registered in the European Clinical Trials Database on 27/9/2019 (registration number: 2018-004672-35).

Continuous surgical multi-level extrapleural block for video-assisted thoracoscopic surgery: a retrospective study assessing its efficacy as pain relief following lobectomy and wedge resection.

Background: Video-assisted thoracoscopic surgery (VATS) causes less postoperative pain than thoracotomy; however, adequate analgesia remains vital. As part of a multi-modal postoperative analgesia, a continuous surgeon-placed extrapleural block catheter is an option. The aim of this retrospective study was to evaluate the analgesic efficacy of a continuous extrapleural block as part of a multimodal analgesic regimen after VATS in general, and VATS lobectomy and wedge resection in particular. Methods: Case records for patients having undergone VATS surgery and been provided a multi-level continuous extrapleural block with an elastomeric pump infusing levobupivacaine 2.7 mg/ml at a rate of 5 ml/h during 2015 and 2016 were reviewed. Pain (Numeric Rating Scale) at rest and mobilisation as well as opioid requirement (daily, postoperative days 0-3, as well as accumulated) were analysed.    Results: In all, 454 records were reviewed: 150 wedge resections, 264 lobectomies and 40 miscellaneous cases. At rest, pain was mild median NRS rated 3-3-1-1 for postoperative day (POD) 0 to 3, during movement, pain was rated moderate during POD 0 and 1 and mild the remaining days (median NRS 4-4-3-3 for POD 0-3). The proportion of patients exhibiting mild pain at rest increased from 55% on POD 0 to 81 % on POD 3. The percentage of patients experiencing severe pain at rest decreased from 15% to 6%. Median oxycodone consumption was 10 mg per day for POD 1-3. Pain after VATS wedge resection was significantly lower at POD 1 and 3 compared to pain after VATS lobectomy. Conclusion: We found a continuous surgeon-placed extrapleural catheter block to be a valuable and seemingly safe addition to our multimodal procedure specific analgesia after VATS. Whether the efficacy of the block can be improved by increasing local anaesthetic and/or adding adjuncts warrants further investigation.

Inhaled isoflurane sedation during therapeutic hypothermia after cardiac arrest: a case series.

OBJECTIVE: Therapeutic hypothermia in the ICU requires mechanical ventilation and sedation. Hypothermia reduces the metabolism of commonly used IV sedatives. The use of long-acting sedative agents may confound neurologic assessment. Volatile anesthetics have been reported to provide protection against ischemia-reperfusion injury and have been safely used in the ICU to provide sedation in trials with shorter wake-up times. There are no clinical studies in this setting. We describe a case series and discuss potential benefits. DESIGN: Retrospective study. SETTINGS: Ten-bed ICU, university hospital. PATIENTS: Twelve patients resuscitated from cardiac arrest with Glasgow Coma Scale score less than or equal to 4. INTERVENTION: Isoflurane sedation with the AnaConDa during 24 hours therapeutic hypothermia, until rewarming. MEASUREMENTS AND MAIN RESULTS: Data were extracted from the computerized ICU chart/monitors, hospital and prehospital charts, and the national death index. Patients were 49-76 years old. Median return of spontaneous circulation was 14 minutes. Glasgow Coma Scale scores were assessed within 24 hours from reaching normal body temperature and compared with outcomes at 6 months: six patients had poor Glasgow Coma Scale scores (< 8) that remained low and all died before 6-month follow-up, whereas another six patients had high scores (> 8) and survived to 6 months with good Cerebral Performance Category. In the ICU, four of the survivors were directly extubated after rewarming while two were once more sedated due to pneumonia requiring invasive ventilator therapy. All patients required norepinephrine to maintain adequate mean arterial pressure. Isoflurane sedation was changed to midazolam in two nonsurviving patients because of hemodynamic instability, which persisted despite the change. CONCLUSIONS: Sedation with volatile anesthetics during therapeutic hypothermia may be a feasible short-acting option with potential postconditioning effects protecting vital organs from ischemia-reperfusion injury. Its measurability and insignificant drug accumulation could facilitate early neurologic assessment. Prospective clinical trials are warranted.

Evaluation of a continuous blood glucose monitoring system using a central venous catheter with an integrated microdialysis function.

INTRODUCTION: Glycemic control in critically ill patients has been the topic of an interesting debate during the last decade. An accurate continuous glucose monitoring system is essential to better understand this field. This prospective study thus evaluates the accuracy and technical feasibility of a continuous glucose monitoring system using intravascular microdialysis. PATIENTS AND METHODS: Thirty patients undergoing cardiac surgery were monitored using a triple-lumen central venous catheter (Eirus TLC; Eirus Medical AB, Solna, Sweden) with an integrated microdialysis function. The catheter functions as a central venous catheter, enabling blood sampling and administration of infusions and medication while simultaneously providing continuous glucose monitoring. The patients were monitored for up to 48 h postoperatively. As reference, arterial blood gas samples were taken every hour and analyzed in a blood gas analyzer. RESULTS: Six hundred seven paired samples were obtained for analysis. Using Clarke Error Grid analysis, 100% of the paired samples were in Zones A+B, and 97% were in Zone A. Mean difference (bias) was -0.12 mmol/L, and mean absolute relative difference was 5.6%. Of the paired samples, 97.5% were correct according to International Organization for Standardization criteria. Bland-Altman analysis showed bias ± limits of agreement were -0.12 ± 0.7 mmol/L. No hypoglycemic episodes were observed. CONCLUSIONS: Central venous microdialysis is an accurate and reliable method for continuous blood glucose monitoring up to 48 h in patients undergoing cardiac surgery. With the microdialysis function integrated in a central venous catheter, no extra device for the continuous glucose monitoring is required. The system may be useful in critically ill patients.

Wake-up times following sedation with sevoflurane versus propofol after cardiac surgery.

OBJECTIVES: Intravenous sedation in the intensive care unit (ICU) may contribute to altered consciousness and prolonged mechanical ventilation. We tested the hypothesis that replacing intravenous propofol with inhaled sevoflurane for sedation after cardiac surgery would lead to shorter wake-up times, quicker patient cooperation, and less delusional memories. DESIGN: Following coronary artery bypass surgery with cardiopulmonary bypass, 100 patients were randomized to sedation with sevoflurane via the anesthetic conserving device or propofol. Study drugs were administered for a minimum of 2 hours until criteria for extubation were met. Primary endpoints were time from drug stop to extubation and to adequate verbal response. Secondary endpoints were adverse recovery events, memories reported in the ICU Memory Tool test, and ICU/hospital stay. RESULTS: Median time from drug stop to extubation (interquartile range/total range) was shorter after sevoflurane compared to propofol sedation; 10 (10/100) minutes versus 25 (21/240) minutes (p <0.001). Time from extubation to adequate verbal response was shorter (p =0.036). No differences were found in secondary endpoints. CONCLUSIONS: Sevoflurane sedation after cardiac surgery leads to shorter wake-up times and quicker cooperation compared to propofol. No differences were seen in ICU-stay, adverse memories or recovery events in our short-term sedation.

Intraoperative blood salvage and retransfusion from citrate treated wounds is safe and feasible.

OBJECTIVES: Allogenic blood transfusions are associated with increased morbidity and mortality in surgical patients. The study objective was to investigate the feasibility and safety of intraoperative autotransfusion of unwashed shed whole blood using a novel method. DESIGN: Twenty pigs were randomised to autotransfusion or crystalloid volume replacement. In two separate surgical wounds, the surfaces and 400 ml of shed blood were treated in situ with citrate, delivered with an equipment transforming suction to positive pressure. Central haemodynamics were monitored with a pulmonary artery catheter. Effects on oxygen-carrying capacity, formed blood elements, haemolysis, inflammation, metabolism, and coagulation were evaluated with biochemical analyses. RESULTS: No clinically relevant adverse effects on haemodynamics were encountered, apart from a decrease in cardiac output and mixed venous saturation similar to that in control animals. Haemoglobin level was better preserved in the autotransfused group (97 vs. 86 g/L, p=0.0007). There were no major differences in biochemical variables and no macroscopic clot formation precluding autotransfusion. CONCLUSIONS: The technique was safe and feasible for intraoperative blood salvage and autotransfusion. Haemodynamics and biochemical variables were similar to controls. The technique warrants further studies in humans, as it may contribute towards a reduction of allogenic blood transfusions.

Aorto-carotid bypass for cerebral malperfusion after aortic dissection surgery: a case report.

Malperfusion syndrome may complicate the postoperative course in patients who have undergone surgery for aortic dissection. In these cases, open surgery or endovascular intervention may be required. We present a case of postoperative onset of intermittent severe neurological symptoms after surgery for type A aortic dissection. Progressive dissection of the carotid arteries was diagnosed, and treatment options were discussed. A successful aorto-carotid bypass was performed by cardiac and vascular surgeons in collaboration. All neurological symptoms were completely resolved. We advocate a high degree of vigilance for signs of cerebral malperfusion in the intensive care unit. Early intervention can result in a successful outcome, as illustrated by this case report.

Intravenous acetaminophen reduced the use of opioids compared with oral administration after coronary artery bypass grafting.

OBJECTIVE: The purpose of this study was to evaluate if intravenous acetaminophen compared to oral administration reduced the consumption of opioids and their side effects without an increase in pain during the stay in the intensive care unit (ICU). DESIGN: Prospective, randomized study. SETTING: An ICU in a university hospital. PARTICIPANTS: Eighty patients with written informed consent undergoing coronary artery bypass grafting with cardiopulmonary bypass. Anesthesia was based on propofol and fentanyl combined with sevoflurane. INTERVENTIONS: Patients were randomized to 2 groups: acetaminophen, 1 g every sixth hour during the postoperative period, either as tablets or intravenously after extubation. MEASUREMENTS AND MAIN RESULTS: The amount of opioids administered during the study period was measured starting with acetaminophen administration during the stay in the ICU until 9 o'clock the following morning. Incidence of postoperative nausea and vomiting (PONV) was noted. Pain was evaluated with a visual analog scale (VAS) from 0 to 10. Three patients, 2 in the oral and 1 in the intravenous group, were excluded because of incomplete data. The intravenous group received less opioids than the orally treated group, 17.4 +/- 7.9 mg compared with 22.1 +/- 8.6 mg (p = 0.016). PONV incidence and VAS scores did not differ. During the first hours after extubation, 50 of 77 patients reported VAS scores >3 with no difference between groups. CONCLUSIONS: Intravenous acetaminophen had a limited opioid-sparing effect when compared with oral administration after coronary artery bypass graft surgery. The opioid-sparing effect was not accompanied by any reduction in the incidence of PONV. The clinical significance of the opioid-sparing effect could therefore be questioned.

Early results with cardiac support device implant in patients with ischemic and non-ischemic cardiomyopathy.

OBJECTIVE: To evaluate the possible beneficial echocardiographic, functional and quality of life improving effects of passive containment surgery using the CorCap Cardiac Support Device in heart failure patients with dilated cardiomyopathy. DESIGN: Eight patients with dilated cardiomyopathy subjected to cardiac surgery received the Cardiac Support Device. Patients with ischemic cardiomyopathy (n = 4) underwent coronary artery bypass surgery receiving one to three bypass grafts. In the idiopathic cardiomyopathy group (n = 4) mitral valve plasty was performed in two patients while two patients received the Cardiac Support Device only. RESULTS: All patients survived the surgery and were discharged to home. There was a gradual, sustained improvement in cardiac dimensions (left ventricular end-diastolic diameter, left ventricular end-systolic diameter) and functional improvement (ejection fraction, 6-min walk, NYHA functional class) as well as quality of life. These beneficial effects developed more rapidly and more extensively in the idiopathic cardiomyopathy group. CONCLUSION: Addition of the Cardiac Support Device to conventional cardiac surgery, or applied alone, is safe and simple. The device seems to reverse ventricular dilatation and improve functional capacity and well-being of heart failure patients with dilated cardiomyopathy. Further studies will delineate what patient population will best benefit from passive containment surgery using the CorCap Cardiac Support Device.

Similar pain scores after early and late extubation in heart surgery with cardiopulmonary bypass.

OBJECTIVE: To investigate if early extubation, 2 hours after surgery, would result in more postoperative pain or in an increased use of opioid analgesics compared with late extubation, 6 hours after surgery. DESIGN: Prospective, randomized study. SETTING: Intensive care unit, university hospital. PARTICIPANTS: Sixty patients undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: Patients were randomized into 2 groups: extubation at about 2 (early) or 6 (late) hours. Anesthesia was based on propofol and remifentanil. There was no epidural analgesia and no local anesthesia in the wound. A bolus of the opioid ketobemidone was administered toward the end of surgery followed by a continuous infusion. MEASUREMENTS AND MAIN RESULTS: Pain, provoked during deep breathing or coughing, evaluated with a visual analog scale (VAS) going from 0 to 10, was measured after extubation, and at 8 and 16 hours after surgery. Unprovoked pain was measured hourly. If VAS was greater than 3, the infusion rate was increased and a bolus of ketobemidone was given. Three patients in the late group were excluded because of incomplete data. Pain did not differ between the early and late groups at any time. In all patients, 21 never scored >3, 11 scored >3 once, and 25 scored >3 more than once. Nine patients had 1 score >5. The amount of ketobemidone was similar in both groups. CONCLUSIONS: Early extubation had no negative effect on the quality of postoperative pain control and was not followed by an increased use of analgesics.

Metabolic changes induced by ischemia and cardioplegia: a study employing cardiac microdialysis in pigs.

OBJECTIVE: The present study investigates dynamic changes of myocardial metabolism in response to ischemia, cardioplegia, and extracorporeal circulation (ECC) in order to differentiate between the contributing effects of each of these interventions. Furthermore, warm blood cardioplegia versus empty beating of the heart were compared as methods to resuscitate the ischemic myocardial metabolism. METHODS: Swedish Landrace pigs on ECC (ECC) were compared with pigs on ECC with warm ischemic cardiac arrest (ischemia) or on ECC with warm ischemic arrest followed by warm blood cardioplegia (ischemia-cardioplegia), using sham-operated pigs as controls (n=7 in each group). Microdialysis probes were placed on the surface of the left ventricle and in the femoral artery for serial evaluation of metabolites in the intracardiac extracellular fluid and arterial blood. When hearts started in ventricular fibrillation (VF), it was electroconverted after 10 min of normal blood reperfusion. If VF started after 10 min of reperfusion electroconversion was immediately performed. RESULTS: There were no differences between groups in arterial contents of serine, citrulline, arginine, inosine, hypoxanthine, guanosine, aspartate, glutamate, pyruvate, or asparagine throughout the observation period. Systemic lactate increased in pigs subjected to ischemia (P<0.001) or ischemia and cardioplegia (P=0.002), highest in the ischemia only group (P=0.002). In left ventricular microdialysates, lactate increased in pigs subjected to ischemia alone (P<0.001 vs. ECC) and ischemia and cardioplegia (P=0.004 vs. ECC). Guanosine increased in ischemia versus ECC (P=0.002), while hypoxanthine was increased in microdialysates of both ischemic (P=0.002) and ischemic-cardioplegic (P=0.001) pig hearts. Inosine was increased in pigs subjected to ischemia and cardioplegia (P<0.001 vs. ECC). All ischemic hearts started with VF, but while in the warm ischemia group VF started within 10 min of reperfusion, the ischemia-cardioplegia group had a longer asystolia with VF starting 11-22 min of blood reperfusion. CONCLUSION: The heart should be allowed to start empty beating rather than by the use of warm continuous blood cardioplegia. Microdialysis and sampling of interstitial metabolites may be advantageous when an increased sensitivity is needed or when repeated blood sampling is difficult or contraindicated in monitoring of the myocardium.

The influence of glucose-insulin-potassium (GIK) on the GH/IGF-1/IGFBP-1 axis during elective coronary artery bypass surgery.

OBJECTIVES: To investigate the influence of glucose-insulin-potassium (GIK) on the growth hormone/insulin-like growth factor-1 axis. DESIGN: Randomized clinical study. SETTING: University hospital. PARTICIPANTS: Twenty patients, without metabolic disorders, admitted for elective aortocoronary bypass surgery. INTERVENTIONS: GIK therapy. Measurements and main results Blood samples were taken repeatedly during the day of surgery. Ejection fraction (EF) was determined by transesophageal echocardiography before and at the end of surgery. Blood samples were taken on the first postoperative day and at discharge (8 am and 8 pm). During coronary artery bypass graft (CABG) surgery, a rapid decrease (44%) in total IGF-1 occurred in both groups. Directly after cessation of extracorporeal circulation, there was a prompt rise in IGFBP-1. The mean peak value in the control group was more than 3 times higher than in the GIK group. GH secretion was stimulated by surgery in both groups and was enhanced by GIK. B-glucose was significantly higher in the control group during surgery. EF ( approximately 55% at baseline) was unchanged in both groups. Postoperatively, there were no differences between the groups (all parameters). At discharge, IGFBP-1 was unchanged, but insulin was elevated compared with preoperative levels. This was seen in both groups, reflecting a hepatic insulin resistance. Conclusions The authors conclude that GIK blunts the rise of IGFBP-1 and thereby increases the bioavailability of IGF-1. GIK also seems to speed up the return of IGF-1 to baseline. Both mechanisms could be of importance to catabolic high-risk patients with low IGF-1. Hence, GIK has favorable effects on the GH/IGF-1 axis during CABG surgery.