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G Cammu

Publications and source records attributed to G Cammu.

14 recordsLinked to original sources

Large bolus dose vs. continuous infusion of cisatracurium during hypothermic cardiopulmonary bypass surgery.

BACKGROUND AND OBJECTIVE: We investigated whether a high bolus dose of cisatracurium (8x ED95) given at induction can provide muscle relaxation for the major part of a cardiac procedure with hypothermic cardiopulmonary bypass, avoid important postoperative residual curarization and cause no waste of product. METHODS: Twenty patients were randomly assigned either to Group 1 (n = 10) or Group 2 (n = 10). Those in Group 1 were given cisatracurium in a high bolus dose (0.4 mg kg(-1)). Those in Group 2 received cisatracurium 0.1 mg kg(-1) at induction followed after 30 min by a continuous infusion of cisatracurium. As an escape medication in case of patient movement, a bolus dose of cisatracurium 0.03 mg kg(-1) was given. RESULTS: In Group 1 (large cisatracurium bolus dose), the clinical duration of effect (until T1/T0 = 25%) was 110 min. Six of 10 patients in Group 1 required additional boluses of cisatracurium intraoperatively. Four of these six had received an additional bolus near the end of surgery and had a train-of-four (TOF) ratio = 0 at the end. The other four patients in Group 1 had a final TOF ratio >0.9. In Group 2 (continuous cisatracurium infusion), only two patients had a TOF ratio >0.9 at the end of surgery, no patient moved and none received additional boluses. The total amount of cisatracurium used in the bolus and infusion Groups was 34.5 +/- 7.8 and 21.3 +/- 5.7 mg, respectively (P = 0.0004). CONCLUSIONS: For continued neuromuscular block during hypothermic cardiac surgery, a high bolus dose of cisatracurium appears to be safe, although it is not an alternative to a continuous infusion, as its neuromuscular blockade does not cover the intraoperative period and a high incidence of movements occurs. In the patients who received a high bolus dose of cisatracurium, postoperative residual curarization appeared after additional boluses had been given. The consumption of cisatracurium by high bolus was significantly greater than with continuous infusion.

Aged↗

Initial experience with an endoscopic radial artery harvesting technique.

OBJECTIVE: The purpose of the study was to investigate the feasibility of an endoscopic radial artery harvesting technique to improve esthetic results and possibly reduce the incidence of neurologic complications observed with the open method. METHODS: Between July 1, 2002, and October 1, 2003, a total of 54 patients underwent endoscopic radial artery harvesting at our institution. Standard endoscopic equipment and a Harmonic Scalpel (Ethicon Endo-Surgery, Inc, Cincinnati, Ohio) were used. Mean age of the patients was 63 +/- 8.1 years, and 16% were female. All patients underwent a preoperative Allen test and duplex ultrasonography to demonstrate adequate ulnar collateral flow. The nondominant arm was used for radial artery harvesting. Mean clinical follow-up was 13 +/- 4.6 months. RESULTS: The artery was harvested through a 3-cm incision at the wrist and was divided at the elbow either through a small counterincision (n = 16) or endoscopically with the use of clips, Endoloop, and endoscopic scissors (n = 38). Mean harvest time was 42.2 +/- 16.9 minutes but decreased from 85 minutes for the first cases to 25 minutes for the last 5 cases. Mean harvested length was 19.6 +/- 1.7 cm. Harvesting complications included 1 conversion, 2 postoperative hematomas, 1 injury, 8 endoscopically controlled bleedings, and 15 cases of at least some superficial radial nerve paresthesia at 6 weeks (clinically relevant in 4 cases). Selective postoperative angiography revealed 1 occluded graft and 1 stenotic graft requiring percutaneous transluminal coronary angioplasty of the native vessel. Eighty-seven percent of the patients were enthusiastic about this new procedure. CONCLUSIONS: Endoscopic radial artery harvesting is a feasible procedure that requires a definite learning curve. Although nerve paresthesias were not completely eliminated in our experience, the technique provided ample patient satisfaction. Further clinical follow-up is required to determine long-term patency rates.

Adult↗

Postoperative residual curarisation: complication or malpractice?

Neuromuscular blocking drugs are often used in anaesthesia; in some types of surgery, their continuous infusion is indicated to limit the otherwise high incidence of movement. A large amount of postoperative residual curarisation is found after a single bolus, but more especially when continuous infusions are used in healthy patients and even more so in those with organ dysfunction or undergoing special types of surgery. Therefore, one should always optimise the dose requirements over time using neuromuscular transmission monitoring. Such monitoring should also help the clinician to antagonise selectively the neuromuscular block at the end of surgery. One should probably avoid routine antagonisation, especially in certain subgroups of patients, until a selective and safe reversal agent has been developed. At present, then, the only objective and reliable guide to facilitating the decision for selective antagonisation is the neuromuscular transmission monitor. Recent data and editorials warning about postoperative residual curarisation after boluses and infusions of neuromuscular blocking drugs have made residual curarisation one of the most feared complications in anaesthesia. There may be a consequent issue of malpractice if neuromuscular transmission monitoring is not used and/or pharmacological antagonisation is not performed.

Anesthesia Recovery Period↗

Implications of the use of neuromuscular transmission monitoring on immediate postoperative extubation in off-pump coronary artery bypass surgery.

BACKGROUND AND OBJECTIVE: When continuous infusions of neuromuscular blocking drugs are administered during lengthy interventions and no routine antagonism of their effects is applied, there is a dramatic incidence of residual curarization. We have examined whether the use of neuromuscular transmission monitoring results in differences in the incidence of postoperative residual curarization, the use of antagonist agents, and the endotracheal extubation rate and outcome after continuous infusion of rocuronium in patients undergoing off-pump coronary artery bypass surgery. METHODS: Twenty patients were assigned to group 1 (n = 10, non-blinded neuromuscular transmission monitoring) or group 2 (n = 10, blinded neuromuscular transmission monitoring). In group 1, patients were given rocuronium at an infusion rate of 6 microg kg(-1) min(-1). The rate was manually adjusted in order to maintain T1/T0 at 10%. In group 2, a rocuronium infusion was started 30 min after induction of anaesthesia, at a rate of 6 microg kg(-1) min(-1); this rate was left unchanged during surgery. The rocuronium infusion was discontinued on completion of all vascular anastomoses; propofol was stopped at the beginning of closure of the subcutis and pirinitramide (piritramide) 15 mg was administered intravenously. Remifentanil was discontinued at the beginning of skin closure and neostigmine (50 microg kg(-1)) administered at the end of surgery when the train-of-four ratio was < 0.9 in group 1, and routinely in group 2. A 20 min test period for spontaneous ventilation was allowed once surgery had been accomplished. When the train-of-four ratio was > or = 0.9 (group 1), patients were extubated if also breathing spontaneously, fully awake and able to follow commands. When they met the clinical criteria for normal neuromuscular function after induced blockade, patients in group 2 were extubated when fully awake and able to follow commands. RESULTS: In group 1, the rate of rocuronium infusion required to keep T1/T0 at 10% was 5 +/- 1.9 microg kg(-1) min(-1); this was not significantly different from the fixed rate in group 2 (P = 0.15). One patient in group 2 was excluded. Eight out of 10 and eight out of nine patients in groups 1 and 2, respectively, reached the extubation criteria. Three out of eight, and five out of eight, patients from groups 1 and 2, respectively, were extubated in the operating room. At that time of endotracheal extubation, all three patients from group 1, but only four of the five patients from group 2 had a train-of-four ratio > or = 0.9. In group 2, one patient was reintubated in the intensive care unit. The incidence of pharmacological reversal was high in group 1. CONCLUSIONS: Although we found no additional benefit of using neuromuscular transmission monitoring, it seems an absolute necessity for safety reasons. Pharmacological antagonism was mandatory. However, in our opinion, it is not wise routinely to perform immediate postoperative extubation in off-pump coronary artery bypass surgery.

Aged↗

Anaesthetic management and outcome in right-lobe living liver-donor surgery.

BACKGROUND AND OBJECTIVE: We reviewed retrospectively the anaesthetic management and perioperative course of eight right hepatectomies for living liver donation. METHODS: After preoperative psychiatric evaluation, eight ASA I-II individuals donated the right lobe of their liver to a family member. A graft-recipient body weight ratio of 0.8-1.0% was required for patient selection. Indications for liver transplantation were: hepatitis C viral-related cirrhosis in six patients; combined hepatitis C and B viral cirrhosis in one patient; multifocal hepatocellular carcinoma--four lesions, involving both liver lobes--of hepatitis C viral-related cirrhosis in another patient. Indication for adult-to-adult living-donor liver transplantation was retained in the latter because of rapid deterioration of liver disease, rare recipient's blood group and extended, unresectable hepatocellular carcinoma. Hepatitis C viral-related cirrhosis was casually the primary indication for adult-to-adult living-donor liver transplantation in this group. The condition of the donated hepatic lobe was optimized by appropriate drug and perfusion management. Preoperative investigations included: blood tests (full cell count and film, thyroid function tests, pregnancy tests, full virological tests and bacteriological cultures, and immunological typing), chest radiograph, electrocardiogram plus Doppler cardiac ultrasound, spirometry, aminopyrine breath test, liver Doppler examination, magnetic resonance imaging, angiography and cholangiography and a volumetric study of the whole liver and the right lobe. Haemoglobin and lactate concentrations, liver function tests and international normalized ratio were measured before and after operation. The volume and weight of the resected right lobe was calculated. Anaesthesia was induced with propofol 300 mL h(-1) and sufentanil 0.3 microg kg(-1) intravenously; cisatracurium, 0.15 mg kg(-1), was given to facilitate tracheal intubation. Anaesthesia was maintained during normocapnic ventilation of the lungs with oxygen 40% in air, isoflurane 1-1.5 MAC and sufentanil. Routine anaesthetic monitoring included electrocardiography, pulse oximetry, invasive blood pressure, central venous pressure, urine output, state of neuromuscular blockade and core temperature. Periods of hypotension (<80% of the preoperative blood pressure) or haemodynamic instability (requiring inotropic or vasoactive support) were registered. Total blood loss and transfusion (homologous, autologous or cell-saver blood) requirements were measured; volume replacements were derived. RESULTS: Data are presented as mean (range). There was no morbidity or mortality and no periods of intraoperative hypotension or haemodynamic instability. The operation time averaged 619 (525-780)min. Four donors were extubated in the operating room immediately after surgery; the others were extubated in the intensive care unit, where the mean extubation time was 16.3 (5-25)h after arrival. The estimated blood loss was 967 (550-1,600)mL. No homologous blood was administered; five donors received autologous blood, intraoperatively; three donors received a cell-saver blood transfusion. Intraoperative fluid replacement was with crystalloids, colloids and 4% albumin. Total urine output was 1,472 (700-3100)mL. Although intraoperative hypothermia occurred all subjects were normothermic at the end of operation. The pre- and immediately postoperative haemoglobin concentration averaged 13.6 (9.8-15.6) and 10.5 (6.9-13.0)gdL(-1), respectively. On the first postoperative day, the haemoglobin was 11.7 (8.4-15.1)gdL(-1). The donors' liver function tests were transiently elevated in the initial postoperative period. The intensive care unit discharge time was 2 (1-3) days. The hospital stay was 13 (7-17) days. There was no morbidity or mortality. CONCLUSIONS: The study demonstrates that right-lobe living-donor surgery was well tolerated, without intraoperative hypotension or haemodynamic instability, without perioperative anaesthetic or surgical complications, and with an excellent general outcome.

Adult↗

Postoperative residual curarization with cisatracurium and rocuronium infusions.

BACKGROUND AND OBJECTIVE: Monitoring of neuromuscular blockade still often relies on clinical judgement. Moreover, there are substantial national differences in the use of agents to 'reverse' their effects. We investigated the recovery characteristics and incidence of postoperative residual curarization after cisatracurium and rocuronium infusions for long duration interventions without systematic antagonism. METHODS: In 30 patients undergoing major surgery, we measured infusion dose requirements for rocuronium and cisatracurium during propofol anaesthesia. Infusions were discontinued at the beginning of surgical closure; spontaneous recovery of neuromuscular function was awaited in both groups. Neostigmine (50 microg kg(-1)) was administered only when a patient started to wake without a train-of-four ratio (TOF) of 0.9. RESULTS: In the cisatracurium and rocuronium groups, four (27%) and one (7%) patients, respectively, had a TOF ratio > or = 0.9 at the end of surgery. The TOF ratio in each group at that time was 51 +/- 32% for cisatracurium and 47 +/- 31% for rocuronium (P = 0.78). Six patients (40%) in the cisatracurium group and seven (47%) in the rocuronium group required neostigmine. The TOF ratio at the time of reversal was 63 +/- 7% for cisatracurium and 40 +/- 19% for rocuronium (P = 0.01). The time interval between the end of surgery and a TOF ratio of 0.9 was 10 +/- 9 min for cisatracurium and 18 +/- 13 min for rocuronium (P = n.s.). CONCLUSIONS: Patients receiving a cisatracurium or rocuronium infusion have a high incidence of postoperative residual curarization when the block is not antagonized. When 'reversal' is not attempted, cisatracurium seems to be safer than rocuronium.

Androstanols↗

Interactions of neuromuscular blocking drugs.

Many drugs interact with neuromuscular blocking drugs and often enhance the induced block; this is of clinical importance for volatile anaesthetics, antimicrobials, magnesium and some more specific drugs. Difficulty in reversing the block occurs with calcium-channel blockers and polymyxin. Phenytoin, carbamazepine and other anticonvulsants may cause resistance to neuromuscular blocking drugs. Moreover, clinically important interactions are found between individual neuromuscular blockers. Giving succinylcholine after a non-depolarizing neuromuscular blocking drug prolongs the onset of succinylcholine; when non-depolarizing drugs are administered after succinylcholine their effects are prolonged. The succinylcholine block is prolonged when the drug is administered during recovery from pancuronium or following neostigmine reversal. Drugs or diseases that decrease the activity of plasma cholinesterase may prolong a succinylcholine-induced block. Finally, liver dysfunction, renal failure, disturbances of acid-base balance, change in temperature and neurological diseases all have an effect on the profile of the neuromuscular blocking drugs; the response to an induced block may be altered in patients under intensive care and those with cancer. Although knowledge of the most important theoretical interactions of neuromuscular blocking drugs is favourable, the anaesthetist should be aware that pharmacological interactions can lead to an unpredictable induced neuromuscular block in many cases in daily clinical practice. Therefore anaesthetists should become familiar with the use of neuromuscular transmission monitoring in order to manage the block correctly.

Anesthetics↗

Dose requirements of infusions of cisatracurium or rocuronium during hypothermic cardiopulmonary bypass.

We investigated the influence of mild hypothermic cardiopulmonary bypass (CPB) on the dose requirements of cisatracurium or rocuronium used as a continuous infusion. We studied eight patients given cisatracurium and nine given rocuronium. They were ASA class III and IV and scheduled for elective coronary artery bypass grafting. Neuromuscular transmission was monitored electromyographically. After recovery of T1/T0 to 10%, a cisatracurium infusion or a rocuronium infusion was started at a rate of 1.5 or 10 micrograms kg-1 min-1, respectively, and adjusted to maintain T1/T0 at 15%. Infusion rate and duration were recorded before, during and after CPB in each patient and the mean infusion rates were calculated. One-way ANOVA showed a statistically significant difference between the cisatracurium infusion rates before, during and after CPB: A T1/T0 of 15% could be achieved with a mean infusion rate of 1.1, 0.75 and 0.98 micrograms kg-1 min-1 before, during and after CPB, respectively. There was no significant difference between the rocuronium infusion rates before, during and after CPB. The mean rocuronium infusion rate required to maintain T1/T0 at 15% throughout the procedure was 4.1 micrograms kg-1 min-1. Cisatracurium infusion rates should be halved during CPB. Even after CPB, requirements are reduced. The same tendency occurs with rocuronium, but the changes in infusion rate were not statistically significant.

Aged↗

Day surgery, including the preoperative assessment of the patient: a UK experience by a Belgian anaesthetist.

In some European countries like Belgium, a lot of hospitals are today dealing with two extremely real issues: adult day surgery and the preoperative anaesthesia consultation. Although efforts are made, there is often still a search for a clear-cut identity on these subjects. As in the rest of Europe, Belgian political, financial and medical driving forces are strongly favouring the shift of surgical procedures towards more day care practice. However, our country has not already reached the level of the United Kingdom, Canada, Australia, or the USA, where the greater majority of all surgery is ambulatory surgery. The development of new surgical technology, however, favours minimal invasiveness, whereas 'newer' anaesthetic agents result in fast recovery. In setting up real surgical day care facilities, Belgian medical and nursing staff, together with the hospital management, will have to cope with the worldwide existing variation in performing ambulatory surgery, at a hospital level, at a surgeon's and anaesthetist's level and at a provision level. Careful patient selection, conscientious anaesthetic management, and being attentive to caring for a patient leaving the hospital, are the cornerstones of decent ambulatory anaesthesia and surgery, and the key for long-term success. Together with dedicated facilities, it is therefore mandatory to have competent and enthusiastic staff. The nursing director, as well as the medical director of the day unit will have to use their power in order to avoid abuse of ambulatory beds for other purposes. As the perioperative specialist, the anaesthetist is ideally suited for the pre-, per-, and postoperative management of the ambulatory patient. Moreover, concerning the preoperative assessment clinic, UK anaesthetists have organized a valuable and interesting alternative to the expensive and time/manpower consuming system used in the USA.

Ambulatory Care Facilities↗

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.

Adult↗