Guy Cammu

Modulation of Portal Graft Inflow: A Necessity in Adult Living-donor Liver Transplantation?

ObjectiveTo evaluate the clinical significance of modulating the recipient portal inflow (rPVF) through perioperative ligation of the splenic artery in adult living-donor liver transplantation (ALDLTx) by focusing on vascular complications, intractable ascites production, and the prevention of small-for-size syndrome (SFSS). Summary Background DataIn ALDLTx, portal graft flow is enhanced to at least twice the donor value, raising the total liver inflow. Recipient hepatic arterial flow (rHAF) is lower than expected. Portal hyperperfusion of small grafts in larger recipients is thought to be one of the main causes of posttransplant graft dysfunction/SFSS. MethodsSeventeen ALDLTx were reviewed for a minimum of 2 months. Patients were divided retrospectively into two groups: G1 (n = 7), without modulation of rPVF, and G2 (n = 10), with splenic artery ligation to decrease rPVF perioperatively. Donor and recipient hepatic hemodynamics were evaluated against graft function and outcome, including correlations between rPVF, graft weight, graft:recipient body weight ratio, and recipient weight. ResultsFollowing portal and arterial reperfusion, mean rPVF and rPVF/graft weight were much higher than in the donors, whereas mean rHAF and rHAF/graft weight were much lower. No differences were found between groups, except for rPVF and rHAF, which were much more higher and lower, respectively, before splenic artery ligation. In G1 patients, SFSS was seen in two patients and vascular complications occurred in two others. In G2 patients, splenic artery ligation permitted a significant decrease in rPVF, an improvement in rHAF, and the resolution of refractory ascites. Neither SFSS nor vascular complications were seen in G2 patients. ConclusionsWhen a suboptimal graft:recipient body weight ratio is accompanied by high rPVF in ALDLTx, the portal flow should be modulated perioperatively; splenic artery ligation is a simple and safe method that is sufficient to allow this modulation in most patients.

Effective reversal of moderate rocuronium- or vecuronium-induced neuromuscular block with sugammadex, a selective relaxant binding agent.

Background:Sugammadex rapidly reverses rocuronium-induced neuromuscular block. This study explored the dose–response relation of sugammadex given as a reversal agent at reappearance of the second muscle twitch after rocuronium- and vecuronium-induced block. A secondary objective was to investigate the safety of single doses of sugammadex. Methods:In this two-center, phase II, dose-finding study, 80 patients (age ≥ 18 yr, American Society of Anesthesiologists physical status I or II, surgery ≥ 60 min requiring muscle relaxation for intubation) were randomly assigned to receive rocuronium (0.60 mg/kg) or vecuronium (0.10 mg/kg). Sugammadex or placebo was administered at reappearance of the second muscle twitch. The primary efficacy endpoint was time from starting sugammadex administration until recovery of the train-of-four ratio to 0.9. Results:Compared with placebo, sugammadex produced dose-dependent decreases in mean time to recovery for all train-of-four ratios in the rocuronium and vecuronium groups. The mean time for recovery of the train-of-four ratio to 0.9 in the rocuronium group was 31.8 min after placebo compared with 3.7 and 1.1 min after 0.5 and 4.0 mg/kg sugammadex, respectively. The mean time for recovery of the train-of-four ratio to 0.9 in the vecuronium group was 48.8 min after placebo, compared with 2.5 and 1.4 min after 1.0 and 8.0 mg/kg sugammadex, respectively. Sugammadex was well tolerated. Conclusion:Sugammadex rapidly reversed rocuronium- or vecuronium-induced neuromuscular block at reappearance of the second muscle twitch and was well tolerated. A dose–response relation was observed with sugammadex for reversal of both rocuronium- and vecuronium-induced neuromuscular block.

Tight perioperative glucose control is associated with a reduction in renal impairment and renal failure in non-diabetic cardiac surgical patients

IntroductionAcute renal failure after cardiac surgery increases in-hospital mortality. We evaluated the effect of intra- and postoperative tight control of blood glucose levels on renal function after cardiac surgery based on the Risk, Injury, Failure, Loss, and End-stage kidney failure (RIFLE) criteria, and on the need for acute postoperative dialysis.MethodsWe retrospectively analyzed two groups of consecutive patients undergoing cardiac surgery with cardiopulmonary bypass between August 2004 and June 2006. In the first group, no tight glycemic control was implemented (Control, n = 305). Insulin therapy was initiated at blood glucose levels > 150 mg/dL. In the group with tight glycemic control (Insulin, n = 745), intra- and postoperative blood glucose levels were targeted between 80 to 110 mg/dL, using the Aalst Glycemia Insulin Protocol. Postoperative renal impairment or failure was evaluated with the RIFLE score, based on serum creatinine, glomerular filtration rate and/or urinary output. We used the Cleveland Clinic Severity Score to compare the predicted vs observed incidence of acute postoperative dialysis between groups.ResultsMean blood glucose levels in the Insulin group were lower compared to the Control group from rewarming on cardiopulmonary bypass onwards until ICU discharge (p < 0.0001). Median ICU stay was 2 days in both groups. In non-diabetics, strict perioperative blood glucose control was associated with a reduced incidence of renal impairment (p = 0.01) and failure (p = 0.02) scoring according to RIFLE criteria, as well as a reduced incidence of acute postoperative dialysis (from 3.9% in Control to 0.7% in Insulin; p < 0.01). The 30-day mortality was lower in the Insulin than in the Control group (1.2% vs 3.6%; p = 0.02), representing a 70% decrease in non-diabetics (p < 0.05) and 56.1% in diabetics (not significant). The observed overall incidence of acute postoperative dialysis was adequately predicted by the Cleveland Clinic Severity Score in the Control group (p = 0.6), but was lower than predicted in the Insulin group (1.2% vs 3%, p = 0.03).ConclusionsIn non-diabetic patients, tight perioperative blood glucose control is associated with a significant reduction in postoperative renal impairment and failure after cardiac surgery according to the RIFLE criteria. In non-diabetics, tight blood glucose control was associated with a decreased need for postoperative dialysis, as well as 30-day mortality, despite of a relatively short ICU stay.

A paravenous approach for the saphenous nerve block

Background and Objectives This study assesses a paravenous approach for saphenous nerve block at approximately the level of the tibial tuberosity, and compares it with the conventional technique of blind subcutaneous infiltration between the tibial tuberosity and the gastrocnemius muscle. Methods In dissections of 5 cadavers, the saphenous nerve was found very close to the saphenous vein bilaterally. Subsequently, in 20 volunteers, a bilateral saphenous nerve block was performed with 5 mL mepivacaine on each side. Randomly assigned, the block was performed by blind subcutaneous injection using a 23-gauge needle of 2.5 cm on one side and by a paravenous subcutaneous approach on the other. Results The paravenous approach produced a saphenous nerve block in all 20 volunteers whereas the blind subcutaneous approach was successful in only 6 (33%) (P < .05). Seven volunteers had a painless minor hematoma at the paravenous site and 2 had a hematoma at the classical site. Conclusion The saphenous nerve can be blocked effectively by a paravenous approach using only 5 mL of local anesthetic solution. This approach is advantageous because of its easily identifiable landmark.

Dynamic Tight Glycemic Control During and After Cardiac Surgery Is Effective, Feasible, and Safe

BACKGROUND: Tight blood glucose control reduces mortality and morbidity in critically ill patients, but intraoperative glucose control during cardiac surgery is often difficult, and risks hypoglycemia. In this study, we evaluated the safety and efficacy of a nurse-driven insulin protocol (the Aalst Glycemia Insulin Protocol) for achieving a target glucose level of 80–110 mg/dL during cardiac surgery and in the intensive care unit (ICU). METHODS: We included 483 nondiabetics and 168 diabetics scheduled for cardiac surgery with cardiopulmonary bypass. To anticipate rapid perioperative changes in insulin requirement and/or sensitivity during surgery, we developed a dynamic algorithm presented in tabular form, with rows representing blood glucose ranges and columns representing insulin dosages based on the patients’ insulin sensitivity. The algorithm adjusts insulin dosage based on blood glucose level and the projected insulin sensitivity (e.g., reduced sensitivity during cardiopulmonary bypass and normalizing sensitivity after surgery). RESULTS: A total of 18,893 blood glucose measurements were made during and after surgery. During surgery, the mean glucose level in nondiabetic patients was within targeted levels except during (112 ± 17 mg/dL) and after rewarming (113 ± 19 mg/dL) on cardiopulmonary bypass. In diabetics, blood glucose was decreased from 121 ± 40 mg/dL at anesthesia induction to 112 ± 26 mg/dL at the end of surgery (P < 0.05), with 52.9% of patients achieving the target. In the ICU, the mean glucose level was within targeted range at all time points, except for diabetics upon ICU arrival (113 ± 24 mg/dL). Of all blood glucose measurements (operating room and ICU), 68.0% were within the target, with 0.12% of measurements in nondiabetics and 0.18% in diabetics below 60 mg/dL. Hypoglycemia < 50 mg/dL was avoided in all but four (0.6%) patients (40 mg/dL was the lowest observed value). CONCLUSIONS: The Aalst Glycemia Insulin Protocol is effective for maintaining tight perioperative blood glucose control during cardiac surgery with minimal risk of hypoglycemia.

Dialysability of sugammadex and its complex with rocuronium in intensive care patients with severe renal impairment

BACKGROUND Renal excretion is the primary route for the elimination of sugammadex. We evaluated the dialysability of sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment in the intensive care unit (ICU). METHODS Six patients in the ICU with acute severe renal impairment received general anaesthesia for transoesophageal echocardiography, to replace their tracheal tubes, or for bronchoscopy. Five of the six patients were in the ICU after cardiac/vascular surgery and one for pneumonia-induced respiratory failure. They all received rocuronium 0.6 mg kg(-1), followed 15 min later by sugammadex 4.0 mg kg(-1). Two patients were studied for two dialysis episodes and four patients for four episodes. Rocuronium and sugammadex concentrations were measured in plasma and dialysate at several time points before, during, and after high-flux dialysis. Dialysis clearance in plasma and dialysate, and reduction ratio (RR) (the extent of the plasma concentration reduction at the end of a dialysis episode when compared with before dialysis) were calculated for each dialysis episode. RESULTS Dialysis episodes lasted on average 6 h. Observed RRs indicated mean reductions of 69% and 75% in the plasma concentrations of sugammadex and rocuronium, respectively, during the first dialysis episode. Reductions were around 50% during sequential dialysis episodes. On average, dialysis clearance of sugammadex and rocuronium in blood was 78 and 89 ml min(-1), respectively. CONCLUSIONS Haemodialysis using a high-flux dialysis method is effective in removing sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment.

Electromyographic activity of the diaphragm during neostigmine or sugammadex-enhanced recovery after neuromuscular blockade with rocuronium: a randomised controlled study in healthy volunteers.

BACKGROUND The use of neuromuscular blocking agents has been associated with severe postoperative respiratory morbidity. Complications can be attributed to inadequate reversal, and reversal agents may themselves have adverse effects. OBJECTIVE To compare the electromyographic activity of the diaphragm (EMGdi) during recovery from neuromuscular blockade using neostigmine and sugammadex. The hypothesis was that there would be better neuromuscular coupling of the diaphragm when sugammadex was used. DESIGN A randomised, controlled, parallel-group, single-centre, double-blinded study. SETTING District general hospital in Belgium. PARTICIPANTS Twelve healthy male volunteers. INTERVENTIONS Individuals were anaesthetised with propofol and remifentanil. After rocuronium 0.6 mg kg−1, a transoesophageal electromyography (EMG) recorder was inserted. For reversal of neuromuscular blockade, volunteers received sugammadex 2 mg kg−1 (n = 6) or neostigmine 70 &mgr;g kg−1 (n = 6). MAIN OUTCOME MEASURES EMGdi, airway pressure and flow were continuously measured during weaning from the ventilator until tracheal extubation. Arterial blood gas samples were obtained for PaO2 and PaCO2 analysis at the first spontaneous breathing attempt and after tracheal extubation. RESULTS During weaning, 560 breaths were retained for analysis. The median (95% CI) peak EMGdi was 1.1 (0.9 to 1.5) &mgr;V in the neostigmine group and 1.6 (1.3 to 1.9) &mgr;V in the sugammadex group (P < 0.001). Individuals in the neostigmine group had 125 of 228 (55%) breaths with associated EMGdi at least 1 &mgr;V vs. 220 of 332 (66%) breaths in the sugammadex group (P = 0.008). The median (95% CI) tidal volume was 287 (256 to 335) ml after neostigmine and 359 (313 to 398) ml after sugammadex (P = 0.013). The median (95% CI) PaO2 immediately after extubation was 30.5 (22.8 to 37.1) kPa after sugammadex vs. 20.7 (12.9 to 27.5) kPa after neostigmine (P = 0.03). CONCLUSION EMGdi, tidal volume and PaO2 following tracheal extubation were increased after sugammadex compared with neostigmine, reflecting diaphragm-driven inspiration after sugammadex administration. Sugammadex may free more diaphragmatic acetylcholine receptors than neostigmine, which has an indirect effect. TRIAL REGISTRATION EudraCT ref: 2013-002078-30.

Management of tight intraoperative glycemic control during off-pump coronary artery bypass surgery in diabetic and nondiabetic patients.

OBJECTIVES To optimize intra- and postoperative insulin management in cardiac surgical patients. DESIGN A prospective, randomized, open-label, single-center study. SETTING A large nonuniversity hospital. PARTICIPANTS Sixty diabetics and 60 nondiabetics undergoing off-pump cardiac bypass surgery. INTERVENTIONS Intra- and postoperative tight glycemic control were achieved using different approaches with a modified insulin protocol. MEASUREMENTS AND MAIN RESULTS Nondiabetics were divided randomly: in the ND-ind group (n = 30), insulin was started at induction according to preinduction blood glucose (BG) concentrations. In group ND >110 (n = 30), insulin was started when BG concentrations exceeded 110 mg/dL during surgery. Up to 85% of the ND >110 group started on insulin intraoperatively. Intraoperatively, the ND-ind group had more BG within target (80-110 mg/dL) (p = 0.002), less BG >130 mg/dL (p = 0.015), and more BG between 70 and 79 mg/dL (p = 0.002). In diabetics, BG concentration was checked every 30 (DM-30), n = 30) versus 60 minutes (DM-60, n = 30) to improve the protocols performance. Intraoperatively, there were more BG concentrations within target (80-110 mg/dL) (p = 0.02) and less >130 mg/dL (p = 0.0002) in the DM-30 group. During surgery, the hyperglycemic index and the glycemic penalty index were lower in the ND-ind group (p < 0.05). Postoperatively, the mean BG concentrations, hyperglycemic index, and glycemic penalty index in diabetics and nondiabetics were comparable between groups (p < 0.05). In the overall 2,641 BG samples, the lowest BG concentration in the operating room was 71 and in the intensive care unit (ICU) it was 61 mg/dL. CONCLUSIONS In diabetics and nondiabetics undergoing off-pump coronary artery bypass surgery, tight perioperative glycemic control is feasible and efficient, with minimal risks for hypo- and hyperglycemia. In nondiabetics, starting insulin therapy from induction onwards results in more measurements within target, without affecting the mean BG. In diabetics, decreasing the sampling interval from 60 to 30 minutes results in more measurements within target and in a mean blood glucose within target at ICU arrival.

Perioperative blood glucose management in patients undergoing tumor hepatectomy

STUDY OBJECTIVE To determine whether our institutional insulin management (modified Atlanta) protocol is efficient and safe in controlling blood glucose levels in the perioperative period in surgical patients undergoing tumor hepatectomy. DESIGN Retrospective study. SETTING Large community hospital. PATIENTS 20 consecutive patients undergoing liver resection for hepatocellular carcinoma, liver metastasis, or other hepatobiliary tumors. INTERVENTIONS AND MEASUREMENTS All patients continuously received intravenous glucose (5% dextrose in water, one mL/kg/hr); insulin was administered according to a strict algorithm, and dose adjustments were based on measurements of whole-blood glucose intraoperatively at one-hour intervals, and in the intensive care unit (ICU). Lower and upper blood glucose limits were set at 85 mg/dL and 110 mg/dL, respectively, in the operating room (OR). In the ICU, lower and upper limits were 90 mg/dL and 140 mg/dL, respectively. MAIN RESULTS Intraoperatively, 51.3% of measurements were within the target range. In the ICU, 75.2% of measurements showed a blood glucose level of 90 - 140 mg/dL. Two of 78 (2.6%) and two of 363 (0.5%) measurements had a blood glucose level < 70 mg/dL in the OR and ICU, respectively. The lowest blood glucose levels were 65 mg/dL (OR) and 66 mg/dL (ICU). CONCLUSIONS The modified Atlanta protocol is efficient and safe in controlling blood glucose levels in the perioperative period of hepatic tumor resection. Because of decreased insulin needs in the ICU, the use of a more liberal algorithm successfully reduced the risk of hypoglycemia.

Diaphragmatic and intercostal electromyographic activity during neostigmine, sugammadex and neostigmine-sugammadex-enhanced recovery after neuromuscular blockade: A randomised controlled volunteer study.

BACKGROUND Electromyographic activity of the diaphragm (EMGdi) during weaning from mechanical ventilation is increased after sugammadex compared with neostigmine. OBJECTIVE To determine the effect of neostigmine on EMGdi and surface EMG (sEMG) of the intercostal muscles during antagonism of rocuronium block with neostigmine, sugammadex and neostigmine followed by sugammadex. DESIGN Randomised, controlled, double-blind study. SETTING Intensive care research unit. PARTICIPANTS Eighteen male volunteers. INTERVENTIONS A transoesophageal EMGdi recorder was inserted into three groups of six anaesthetised study participants, and sEMG was recorded on their intercostal muscles. To reverse rocuronium, volunteers received 50 &mgr;g kg−1 neostigmine, 2 mg kg−1 sugammadex or 50 &mgr;g kg−1 neostigmine, followed 3 min later by 2 mg kg−1 sugammadex. MAIN OUTCOME MEASURES We examined the EMGdi and sEMG at the intercostal muscles during recovery enhanced by neostigmine or sugammadex or neostigmine–sugammadex as primary outcomes. Secondary objectives were the tidal volume, PaO2 recorded between the onset of spontaneous breathing and extubation of the trachea and SpO2 during and after anaesthesia. RESULTS During weaning, median peak EMGdi was 0.76 (95% confidence interval: 1.20 to 1.80) &mgr;V in the neostigmine group, 1.00 (1.23 to 1.82) &mgr;V in the sugammadex group and 0.70 (0.91 to 1.21) &mgr;V in the neostigmine–sugammadex group (P < 0.0001 with EMGdi increased after sugammadex vs. neostigmine and neostigmine–sugammadex). The median peak intercostal sEMG for the neostigmine group was 0.39 (0.65 to 0.93) &mgr;V vs. 0.77 (1.15 to 1.51) &mgr;V in the sugammadex group and 0.82 (1.28 to 2.38) &mgr;V in the neostigmine–sugammadex group (P < 0.0001 with sEMG higher after sugammadex and after neostigmine–sugammadex vs. neostigmine). CONCLUSION EMGdi and sEMG on the intercostal muscles were increased after sugammadex alone compared with neostigmine. Adding sugammadex after neostigmine reduced the EMGdi compared with sugammadex alone. Unlike the diaphragm, intercostal EMG was preserved with neostigmine followed by sugammadex. TRIAL REGISTRATION EudraCT: 2015-001278-16; ClinicalTrials.gov: NCT02403063.