Biomedical subjects

B Debaene

Publications and source records attributed to B Debaene.

At least 37 records · Page 2Linked to original sources

PubMed1999

Visual estimation of onset time at the orbicularis oculi after five muscle relaxants: application to clinical monitoring of tracheal intubation.

UNLABELLED: The onset time of neuromuscular blockade at the adductor pollicis (AP) is different among neuromuscular blocking drugs, but these discrepancies had never been studied at the orbicularis oculi (OO). The purpose of this study was to verify if the differences in onset time observed at the AP still existed at the OO and to score the intubating conditions using monitoring at the OO after five muscle relaxants. The study included 172 adults aged 18-75 yr. Anesthesia was induced with fentanyl and propofol. Atracurium (0.5 mg/kg), mivacurium (0.20 mg/kg), rocuronium (0.6 mg/kg), succinylcholine (1.0 mg/kg), or vecuronium (0.08 mg/kg) was injected by random allocation. Time to complete disappearance of the response at the OO was assessed visually after train-of-four stimulation of the facial nerve. Laryngoscopy was then performed, and intubating conditions were determined on a scale of 1-4. Results were based on 150 patients. Onset time at the OO was (mean +/- SD): succinylcholine (57 +/- 17 s) < mivacurium (99 +/-19 s) = rocuronium (99 +/- 47 s) < atracurium (129 +/-33 s) = vecuronium (135 +/- 38 s) (P < 0.05). Overall intubating conditions were excellent (84%), good (14%), poor (1.3%), impossible (0.7%), and were similar among the five groups. We conclude that differences in onset time of muscle relaxants observed at the AP were also found at the OO. Visual estimation of the response at the OO correctly predicted good-to-excellent intubating conditions in more than 90% of cases for all the currently available muscle relaxants. IMPLICATIONS: Onset time of neuromuscular blockade, as estimated visually at the orbicularis oculi, depends on the muscle relaxants given. Regardless of the relaxant used, intubating conditions at loss of orbicularis oculi are acceptable.

Adolescent↗

PubMed1998

[Acute cardiogenic postoperative edema after doxorubicin (adriamycin) chemotherapy].

We describe a case of postoperative congestive heart failure in a young woman of physical class ASA 1, following breast cancer surgery. Preoperatively she had been treated with doxorubicin (Adriamycin) 450 mg.m-2, total dose, associated with breast and ovarian radiotherapy. This association was probably the cause of postoperative heart failure. Twenty-four hours after surgery, a two-dimensional echocardiography showed a severe left ventricular dysfunction, whereas preoperative clinical assessment was unremarkable. Doxorubicin cardiotoxicity can be acute, subacute and delayed as in our case. Clinical assessment and ECG are not sensitive indicators of such cardiac damage. Preoperative echography is the technique of choice for the evaluation of the cardiac status of a patient treated with a high cumulative dose of doxorubicin and mediastinal irradiation.

Adenocarcinoma↗

PubMed1998

[Use of sevoflurane for surgery of pheochromocytoma].

Resection of phaeochromocytoma is associated with sudden changes in arterial pressure. Pharmacodynamic and pharmacokinetic properties of sevoflurane are suitable for maintenance of haemodynamic stability. We report two cases of phaeochromocytoma resection using sevoflurane. Intraoperative hypotensive or hypertensive events have been rapidly controlled, most often only by adjustment of the end-expiratory fraction of sevoflurane.

Adrenal Gland Neoplasms↗

PubMed1998

[What are the real indications for hepatectomies in metastases of colorectal origin?].

AIM: To ascertain the real impact of classical contraindications (relative or absolute according to various authors) represented by: a high number of liver metastases (LM), the presence of associated extra-hepatic localizations (EHL), and a surgical margin less than 10 mm. METHODS: A prospective study was conducted in 269 consecutive hepatectomized patients. Inclusion criteria were only the resection of all tumoral tissue, and lack of major operative risk. Fifty-nine patients had at least 4 LM, 62 had an associated EHL, and 187 had a surgical margin < 10 mm. Altogether, 83% of the patients did not match the classical selection criteria. Sixty-two parameters were registered. A uni- and multivariate study of prognostic factors was performed. RESULTS: Although 18% of the resections were palliative (R1 or R2 according to the UICC classification), and the hospital mortality was 3.3% (2.2% during the first postoperative month), global and disease-free 5-year survival rates were 34.4% and 23.3%, respectively. The number of LM had no prognostic implication. A surgical margin > 9 mm improved significantly the prognosis. Between 0 and 9 mm, it had no important prognostic impact if the cut surface was histologically disease-free. A margin < 10 mm was greatly associated with a high number of LM, a bilateral localization of LM, and extended hepatectomy. Among the EHL, only those discovered during laparotomy had a significant adverse impact on prognosis. CONCLUSION: Fundamental principles of the indications of hepatectomy for colorectal LM are to resect all the lesions and to avoid major operative risk. In complex cases, the most frequent, these principles can only be completely followed in a specialized center.

Adolescent↗

PubMed1997

ORG 9487 neuromuscular block at the adductor pollicis and the laryngeal adductor muscles in humans.

BACKGROUND: ORG 9487 is a new steroidal nondepolarizing muscle relaxant with a rapid onset of action. This study was designed to determine the neuromuscular blocking profile of ORG 9487 at the adductor muscles of the larynx and the adductor pollicis. METHODS: In 30 adults, anesthesia was induced with propofol (2-5 mg/kg) and fentanyl (2-3 microg/kg). After train-of-four stimulation, the block of the laryngeal adductor muscles was evaluated by measuring the pressure changes in the cuff of the tracheal tube placed between the vocal cords, and the force of the contraction of the adductor pollicis was measured with a force transducer. Patients were randomly allocated to receive ORG 9487 at intravenous bolus doses of 0.75, 1.5 or 2 mg/kg (n = 10 in each group). RESULTS: Time to peak effect was significantly shorter at the vocal cords than at the adductor pollicis muscle (P < 0.001). Onset time at the vocal cords was 62 +/- 16 s, 62 +/- 13 s, and 52 +/- 14 s (mean +/- SD) after doses of 0.75, 1.5, and 2 mg/kg, respectively (not significant). Onset time at the adductor pollicis muscle was 126 +/- 33 s, 96 +/- 20 s, and 82 +/- 21 s after 0.75, 1.5, and 2 mg/kg doses, respectively (P < 0.001). Maximum block was significantly less intense at the vocal cords than at the adductor pollicis muscle (69 +/- 15% vs. 94 +/- 4% after 0.75 mg/kg; 86 +/- 7% vs. 97 +/- 4% after 1.5 mg/kg; and 91 +/- 5% vs. 99 +/- 1% after 2 mg/kg). After 1.5 mg/kg duration to 25%, recovery was 3.7 +/- 2.2 min versus 10.2 +/- 2.5 min at the vocal cords and the adductor pollicis muscle, respectively, and 75% recovery occurred at 9.7 +/- 3.7 min at the vocal cords and at 18.3 +/- 5.2 min at the adductor pollicis muscle. CONCLUSIONS: ORG 9487 has a rapid onset of action at the laryngeal adductor and the adductor pollicis muscles. Onset and duration of action are faster at the vocal cords than at the adductor pollicis muscle. However, the maximum block obtained at the laryngeal muscles was less than at the adductor pollicis, regardless of the dose of ORG 9487.

Adult↗

PubMed1996

Mivacurium neuromuscular block at the adductor muscles of the larynx and adductor pollicis in humans.

BACKGROUND: Laryngeal muscles must be paralyzed for tracheal intubation. Time to peak effect (onset time) is shorter and intensity of blockade is less at laryngeal muscles compared with the adductor pollicis. The authors' aim in this study was to determine the neuromuscular effects of mivacurium at the laryngeal adductor muscles and the adductor pollicis. METHODS: In 22 adults, anesthesia was induced and maintained with propofol and alfentanil. The force of contraction of the adductor pollicis was recorded, and the laryngeal response was evaluated by measuring the pressure change in the cuff of a tracheal tube positioned between the vocal cords after train-of-four stimulation. Mivacurium (0.07 mg.kg-1 or 0.14 mg.kg-1) was given intravenously (10s). RESULTS: With 0.07 mg.kg-1 mivacurium, onset time was 151 +/- 40 s(mean +/- SD) at the larynx and 241 +/- 79 s at the adductor pollicis, respectively (P < 0.005). Maximum block was 78 +/- 18% and 95 +/- 8%, respectively (P < 0.002), and time to 90% recovery was 11.1 +/- 2.9 min and 23.3 +/- 7.6 min, respectively (P < 0.001). With 0.14 mg.kg-1 mivacurium, onset time also was more rapid at the vocal cords (137 +/- 20 s) than at the adductor pollicis (201 +/- 59 s, P < 0.01). Maximum block was 90 +/- 7% and 99 +/- 1% (P < 0.005), and time to 90% recovery was 16.4 +/- 4.9 min and 27.4 +/- 7.8 min, respectively (P < 0.01). CONCLUSIONS: With mivacurium, onset and recovery are faster at the laryngeal muscles, but block is less intense than at the adductor pollicis. A dose greater than 0.14 mg.kg-1 mivacurium is necessary to ensure complete relaxation at the vocal cords.

Adult↗

PubMed1995

Intermittent vascular exclusion of the liver (without vena cava clamping) during major hepatectomy.

Intermittent vascular exclusion of the liver (IVEL) combines clamping of the hepatic pedicle with clamping of the main hepatic veins without interruption of caval flow. In this retrospective study, eight cases of total IVEL and eight of partial IVEL were analysed (involving only the middle and left hepatic veins) during major hepatectomy for malignant tumours. Liver parenchyma was pathological in nine cases. IVEL was feasible in 16 of the 18 attempts and was efficient in reducing bleeding during hepatectomy in 15 cases. Mean duration of IVEL was 60.2 (range 37-140) min, mean blood loss was 1230 (range 300-2800) ml and there were no postoperative complications related to the procedure. The major advantages of this technique of liver vascular exclusion (good tolerance and possibility of long duration) merit its inclusion in the list of different clamping techniques available for use during hepatectomy.

Adult↗

PubMed1995

Pharmacokinetics and pharmacodynamics of rocuronium at the vocal cords and the adductor pollicis in humans.

The pharmacokinetic-pharmacodynamic relationship of rocuronium at the laryngeal adductor muscles and the adductor pollicis was determined in eight patients during general anesthesia. Rocuronium was administered as an infusion at a rate of 100 micrograms.kg-1.min-1 over 5 minutes. The half-life of transport between plasma and biophase (effect compartment) was significantly shorter at the adductor laryngeal muscles (2.7 +/- 0.6 minutes, mean +/- SD) than at the adductor pollicis (4.4 +/- 1.5 minutes, p = 0.003). The concentration in the effect compartment producing 50% of the maximum effect was significantly greater at the adductor laryngeal muscles (1424 +/- 148 micrograms.L-1) than at the adductor pollicis (823 +/- 157 micrograms.L-1, p = 0.0001). The shorter onset of neuromuscular blockade at the laryngeal muscles than at the adductor pollicis may be explained by a faster transfer rate at the laryngeal adductor muscles neuromuscular junction than at the adductor pollicis neuromuscular junction.

Adult↗

PubMed1995

Monitoring the onset of neuromuscular block at the orbicularis oculi can predict good intubating conditions during atracurium-induced neuromuscular block.

This study was designed to assess whether monitoring the orbicularis oculi (OO) can predict good tracheal intubating conditions. Fifty patients, ASA grade I or II were studied. Anesthesia was induced with thiopental (5 mg/kg) and fentanyl (3 micrograms/kg). The ulnar and facial nerves were simultaneously stimulated using train-of-four (TOF) stimulations every 10 s. The responses of the adductor pollicis (AP) and the OO were estimated visually. Patients were randomly allocated to receive either atracurium 0.5 mg/kg (n = 30) or 0.3 mg/kg (n = 20). In each group, endotracheal intubation was performed randomly when the OO or the AP was completely blocked. If complete block was not obtained, intubation was performed 300 s after administration of atracurium. Intubating conditions were scored on a 1 to 4 scale. All intubations were performed by the same physician unaware of the dose and the muscular responses. After 0.5 mg/kg, both muscles were completely blocked in all patients. The average onset time (time from the injection of atracurium to the disappearance of all muscular responses after TOF) was shorter at the OO (2.35 +/- 0.12 min) than at the AP (3.59 +/- 0.15 min) (P < 0.001) (mean +/- SD). Endotracheal intubating conditions were comparable in both groups: good or excellent after 0.5 mg/kg. After 0.3 mg/kg, complete block was achieved only 2/20 at the OO and 12/20 at the AP. Intubating conditions were comparable in both groups: poor or inadequate, except in the two patients with complete OO block, for whom conditions were good.(ABSTRACT TRUNCATED AT 250 WORDS)

Atracurium↗

PubMed1994

Neuromuscular effects of vecuronium and neostigmine in Montreal and Paris.

The potency of vecuronium was reported to be greater in Montréal than in Paris. This study was designed to determine whether there were differences in onset, duration, and reversibility with neostigmine between both centres. Twenty ASA I or II adults (ten men, ten women), aged 18-65 yr were studied in each of the two cities, during a standard thiopentone-fentanyl-nitrous oxide (60-70%) - isoflurane 0.5% end-tidal anaesthetic. Train-of-four stimulation was applied every 20 sec to the ulnar nerve at the wrist and the force of contraction of the adductor pollicis muscle was measured. Vecuronium, 0.1 mg.kg-1, was given as a bolus, and neostigmine, 0.04 mg.kg-1, was administered, with atropine 0.02 mg.kg-1, at 25% first twitch height recovery. Onset time to maximum blockade was (mean +/- SD) 3.9 +/- 1.3 min in Paris vs 4.5 +/- 1.3 min in Montréal (NS). Duration from injection to 25% first twitch recovery was shorter (28.5 +/- 6.8 min) in Paris than in Montréal (39.1 +/- 7.3 min) (P < 0.0001). Time from injection of neostigmine to a train-of-four ratio of 70% was not different in Paris (6.3 +/- 2.2 min) from Montréal (5.6 +/- 1.9 min). It is concluded that the duration of an "intubating" dose of vecuronium is longer in Montréal, but, when given at 25% first twitch recovery, neostigmine has the same efficacy in Montréal as in Paris.

Adolescent↗

PubMed1994

Visual estimation of train-of-four responses at the orbicularis oculi and posttetanic count at the adductor pollicis during intense neuromuscular block.

Posttetanic count (PTC) predicts the time to return of train-of-four (TOF) responses at the adductor pollicis (AP) muscle. The duration of neuromuscular block at the orbicularis oculi (OO) is shorter than at the AP. The aim of this study was to assess whether TOF at the OO can predict, as accurately as PTC does, the time to return of TOF at the AP. Twenty patients, ASA grade I or II, were studied. Anesthesia was induced with propofol, 2-3 mg/kg, intravenously (IV), and fentanyl, 2-3 micrograms/kg IV, and maintained with a propofol infusion. Ulnar and facial nerves were stimulated simultaneously with TOF every 20 s. PTC at the AP was repeated every 5 min. The number of twitches after PTC was estimated by feeling the responses at the thumb. TOF responses at the OO were monitored visually. TOF responses at the AP were recorded using a force transducer. Patients were assigned randomly to receive either atracurium, 0.5 mg/kg (n = 10), or pancuronium, 0.1 mg/kg (n = 10). Times from injection to the first response to PTC (PTC1), to the reappearance of the first response of TOF at the OO (T1OO), and to the reappearance of the first response of TOF at the AP (T1AP) were recorded. After pancuronium and atracurium, PTC1 and T1OO recovered before T1AP (P < 0.001). In all patients, PTC1 recovered earlier than T1OO (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Intravenous↗

PubMed1994

[Intraperitoneal hyperthermic chemotherapy (IPHC), a promising treatment of peritoneal carcinomatosis].

Intraperitoneal hyperthermic chemotherapy (IPHC) appears to be a promising treatment of peritoneal carcinomatosis. This paper reports the physio-pathological background of IPHC and the various studies which have been published in the literature. It points out the heterogeneity of these series and discuss the most critical points as surgical indications, choice of the antineoplastic drugs, their doses, temperatures of the IPHC, extend of the cytoreductive surgery, morbidity and mortality. Finally, several options are proposed for those points which are not yet standardized.

Animals↗

PubMed1994

Treatment of peritoneal carcinomatosis by intraperitoneal chemo-hyperthermia: reliable and unreliable concepts.

Intraoperative peritoneal chemo-hyperthermia (IPCH) is a promising treatment of peritoneal carcinomatosis arising from digestive tumors. After presenting the rationale for the use of IPCH, this review reports the results published to date by different groups. Unfortunately, data with respect to technical aspects, indications and results are unclear, inhomogeneous and questionable. The discussion presents reliable and unreliable points, mainly concerning the technical aspects of IPCH: what is the maximal desirable tumor thickness before initiating treatment? What is the ideal temperature? Is central hyperthermia beneficial? What is the ideal duration? What is the most effective antimitotic drug? A new classification of peritoneal seeding before cytoreductive surgery and before the initiation of IPCH, is proposed, and a suggestion concerning the reporting of drug concentrations made. Numerous prospective studies need to be conducted to test different technical modalities and to evaluate the results of IPCH.

Animals↗

PubMed1993

Repeat hepatectomy for cancer.

In a series of 279 hepatectomies performed for cancer between June 1984 and March 1992, 46 were repeat operations, for metastases in 41 patients. The primary tumour was in the colon and rectum (28 patients), APUDoma (five) and miscellaneous (eight). Repeat hepatectomies were performed in 26 per cent of patients who had recurrence after the first liver resection and in 40 per cent of those who had liver recurrence. An unsuspected extrahepatic recurrence was discovered and resected in eight instances and in two other cases a known extrahepatic recurrence was resected during the second hepatectomy. The hospital mortality rate was 2 per cent (one patient); the death was from nosocomial pneumonia. The total morbidity rate including minor complications was 32 per cent, with a higher frequency of haemorrhagic problems after secondary liver resection (12 per cent) than after primary hepatectomy (5 per cent). The rate of postoperative complications after repeat hepatectomy was related significantly to operative blood loss greater than 1500 ml (P = 0.04). The technical problems of repeat hepatectomy were: (1) re-exposure of the liver, considered to be difficult in 67 per cent of second liver resections and 80 per cent of third procedures; (2) the liver parenchyma, which often had histological modifications between first and second resections and was more difficult to 'work' as shown by the mean duration of clamping of the hepatic pedicle (54 min for secondary versus 36 min for primary liver resection); and (3) modification of the intraparenchymal vasculobiliary anatomy following liver regeneration after major hepatectomy. Intraoperative ultrasonography was of great benefit. Rates of crude and recurrence-free survival were relatively encouraging at 47 and 33 per cent 3 years after the second liver resection for the whole group. These values were lower for colorectal cancer (37 and 21 per cent 3 years after the second hepatectomy). These figures do not, however, convey the complete picture of the outcome for these patients. During the same follow-up period, 143 recurrences were detected and a mean of 2.9 resections per patient were performed. The indications for repeat hepatectomy are still to be clarified, although the surgical technique is safe.

Adult↗

PubMed1993

Respiratory mechanics in anaesthetised patients after neostigmine-atropine. A comparison between patients with and without chronic obstructive pulmonary disease.

The aim of this study was to compare the effects of pharmacological reversal of neuromuscular blockade on static compliance and resistance in patients with and without chronic obstructive pulmonary disease (COPD). Twenty patients were studied: 12 patients were free of respiratory disease (NCOPD) and had normal pulmonary function tests. Eight subjects (COPD) had a clinical history of chronic bronchitis and a FEV1 < 70% of the predicted value. All patients were anaesthetised with a continuous infusion of methohexitone and alfentanil. Airway pressure (Paw) was recorded continuously. Static compliance (Crs) was calculated from the relationship between 21 syringe volume (250 ml step) and Paw. Total respiratory resistance (Rrs) was measured at two levels of inspiratory flow and tidal volume. These measurements were made before vecuronium (control), after injection of vecuronium to abolish the first neuromuscular response to train of four, 5 and 15 min after administration of neostigmine 40 micrograms.kg-1 and atropine 10 micrograms.kg-1. In COPD patients Crs and Rrs were significantly greater (1450 +/- 580 ml.kPa-1 and 1.06 +/- 0.68 kPa.l-1.s-1) than in normal patients (1000 +/- 380 ml.kPa-1 and 0.58 +/- 0.22 kPa.l-1.s-1) (P < 0.01). In both groups Crs and end-expiratory pulmonary volume were similar before injection of vecuronium and after neostigmine-atropine administration. In both groups, Rrs was not altered significantly by neostigmine-atropine for the two inspiratory flows. These results suggest that neostigmine-atropine mixture is associated with small changes in respiratory mechanics, and the changes are similar in COPD compared with normal patients.

Airway Resistance↗

PubMed1993

[Triple hepatectomy for cancer].

The resection of the metastases from digestive malignant lesions are always the most efficient treatment, if it is complete. However it must be performed without major operative risk. According to this point of view, it is logical to examine the feasibility of three successive hepatectomies for metastases. We report in this study our experience with five cases of triple hepatectomies performed for 4 colic cancers and 1 carcinoid cancer. Two major hepatectomies were performed during this third resection. The re-exposure of the liver was very difficult in 4 cases, and the texture of the liver parenchyma was flabby and abnormal in 5 cases (confirmed with the histologic study). The mean duration of the surgery was 307 minutes, the mean duration of the intermittent pedicle clamping was 59 minutes, and the mean blood loss was 1710 ml. No post-operative death occurred, and the morbidity was low. This 5 third hepatectomies have been compared, for the feasability, to the 41 second hepatectomies and to the 234 first hepatectomies which we have performed. In proportion as hepatectomies are carried out, the difficulties to expose the liver increase, the texture of the liver parenchyma gets spoiled and the duration of the operation increases. In conclusion, the third hepatectomies are technically difficult to perform, but they are feasable. However it is too early to be able to define their indications.

Adenocarcinoma↗

PubMed1992

Plasma catecholamine concentrations are a reliable index of sympathetic vascular tone in patients with cirrhosis.

In patients with cirrhosis, the significance of elevated plasma catecholamine concentrations is unclear. Thus we investigated the relationship between plasma catecholamine concentrations and the hemodynamic effect of pindolol (an index of sympathetic vascular tone) in 10 patients with cirrhosis. Systemic and splanchnic hemodynamics and plasma catecholamine concentrations in the pulmonary artery and the splanchnic veins (hepatic and azygos veins) were studied before and after the oral administration of pindolol (20 mg). In basal conditions patients exhibited a hyperkinetic circulatory syndrome and elevated plasma catecholamine concentrations. Alterations in basal hemodynamics were correlated with plasma epinephrine concentrations but not with norepinephrine. Pindolol administration significantly decreased heart rate and increased right atrial pressure. After pindolol administration, individual hemodynamic changes (cardiac index, systemic vascular resistance, wedged hepatic venous pressure) were significantly correlated with plasma catecholamine concentrations. In conclusion, this study shows that in cirrhotic patients epinephrine may play a role in hemodynamic alterations, and plasma catecholamine concentrations are an index of sympathetic vascular tone.

Epinephrine↗

PubMed1992

[Effects of halogenated anesthetics on splanchnic hemodynamic in normo- and hypovolemic cirrhotic rats].

The effects of 1 MAC of either halothane, enflurane or isoflurane on splanchnic haemodynamics were studied in cirrhotic rats that were either normovolaemic or hypovolaemic from haemorrhage. A group of conscious rats acted as the control group. Bile duct ligation had been carried out in all the rats four weeks previously to induce cirrhosis. At the time of the study, all the rats were anaesthetized with ether for catheterization of the left femoral artery and vein, and the left ventricle via the right carotid. The control group was allowed to awake. When the other rats started to recover, they were artificially ventilated with room air and 1 MAC of the halogenated agent. Heart rate and mean arterial blood pressure were monitored continuously. Once the animals had remained steady for one hour, 1.25 ml of blood for 100 g body weight was removed over a 10 min period. PaO2, PaCO2, arterial pH, heart rate, mean arterial blood pressure, cardiac index and regional blood flows (RBF) were measured before, and thirty minutes after the haemorrhage. Cardiac output and RBF were measured using the radioactive-labelled microsphere method. Only 32 animals were finally included, eight in each group. Splanchnic, portal and hepatic arterial blood flows were similar in conscious rats and in those receiving isoflurane or halothane, and were higher than in those receiving enflurane. The lowest splanchnic and portal venous blood flows were found in those rats receiving enflurane. After haemorrhage, these RBF decreased significantly in all groups except in the enflurane group.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗