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P Bonnichon

Publications and source records attributed to P Bonnichon.

At least 19 recordsLinked to original sources
PubMed2004

Video-assisted thoracoscopic surgery as a first-line treatment for mediastinal parathyroid adenomas: strategic value of imaging.

OBJECTIVE: To present first-line thoracic surgery made possible by localization studies in three patients with ectopic parathyroid adenomas. DESIGN AND METHODS: Three patients with ectopic parathyroid tissue in the mediastinum were examined by ultrasound, technetium-99m sestamibi scintigraphy, computed tomography (CT), and venous catheterization with measurement of parathyroid hormone. Without previous cervical exploration, video-assisted thoracic surgery (VATS) was used in all cases to avoid the need for thoracic open surgical procedures. RESULTS AND CONCLUSIONS: The mediastinal parathyroid glands were all detected at scintigraphy, and CT and venous catheterization were helpful in anatomic and functioning characterization. All pathologic glands were successfully resected, with only one minor complication. VATS can safely remove a deep mediastinal parathyroid adenoma and avoid more aggressive open approaches. In an experienced referral center, systematic and sophisticated imaging studies may accurately identify and localize rare ectopic parathyroid adenomas, and avoid cervical surgery.

Adenoma↗
PubMed2003

Remifentanil-propofol vs. sufentanil-propofol: optimal combinations in clinical anesthesia.

BACKGROUND: Two opioid regimens, computer-simulated to provide optimal general anesthesia in combination with propofol, were compared using clinical criteria. METHODS: Fifty patients undergoing thyroid surgery were blindly, prospectively and randomly allocated to receive either (a) i.v. remifentanil (1.5 micro g kg-1, followed by 0.2 micro g kg-1 min-1) or (b) i.v. sufentanil (0.2 micro g kg-1 followed by 0.2 micro g kg-1 h-1). Remifentanil infusion was stopped at the last skin suture. Sufentanil infusion was stopped 30 min before the end of surgery. Intravenous propofol was titrated to keep BIS at 50+/-5. Remifentanil and sufentanil groups were compared with regards to (a) propofol delivery, (b) hemodynamic and recovery variables, and (c) effect-site propofol levels during a steady-state period for effect-site remifentanil and sufentanil levels. P<0.05 was significant. RESULTS: Groups were similar in demographic data; types and durations of surgery; total propofol consumption; and response, extubation and emergence times. During the steady-state period for the opioid delivery, the remifentanil and sufentanil effect-site levels were 5.3 ng ml-1 and 0.18 ng ml-1, respectively (potency ratio=30). In both opioid groups, in accordance with previous computer-simulations, the effect-site propofol concentrations remained (a) within a narrow range unaffected by surgical stimuli, (b) significantly smaller in the remifentanil group than in the sufentanil group, but (c) smaller than expected from previous computer-simulations. More patients required ephedrine following induction of anesthesia in the remifentanil compared with the sufentanil group. CONCLUSIONS: The present clinical trial conducted in thyroid surgery is consistent with previous computer-simulated opioid-propofol combinations with respect to intraoperative and recovery variables. Effect-site propofol ranges were, however, lower than expected.

Adult↗
PubMed2003

Bispectral index changes following etomidate induction of general anaesthesia and orotracheal intubation.

BACKGROUND: Etomidate-associated hypnosis has only been studied using standard clinical criteria and raw EEG variables. We conducted a BIS-based investigation of etomidate induction of general anaesthesia. METHODS: Thirty hydroxyzine-premedicated ASA I patients were randomly allocated to receive etomidate 0.2, 0.3, or 0.4 mg kg(-1) intravenously over 30 s. The BIS was continuously recorded. A tourniquet was placed on a lower limb to record purposeful movements and myoclonia. Tracheal intubation was facilitated using rocuronium 0.6 mg kg(-1) when the BIS value was 50. The times to disappearance of the eyelash reflex, to a decrease in the BIS to 50, and to tracheal intubation were compared. The BIS values 30 s following tracheal intubation, and mean arterial pressure (MAP) and heart rate (HR) at all time points were also recorded. RESULTS: The BIS value decreased to 50 for tracheal intubation with no purposeful movement in all but one patient in the 0.2 mg kg(-1) group. There was no difference between the etomidate groups (0.2, 0.3, and 0.4 mg kg(-1)) in regards to time to loss of the eyelash reflex (103 (67), 65 (34), 116 (86) s, P=0.2), or to a decrease in BIS to 50 (135 (81), 82 (36), 150 (84) s, P=0.1). Also, the BIS value 30 s after intubation (41 (10), 37 (4), 37 (4), P=0.4), and plasma etomidate concentrations (161 [29-998], 308 [111-730], 310 [90-869] ng ml(-1), P=0.2) did not differ between groups. The time to loss of the eyelash reflex was 12-140 s shorter than the time to a decrease in BIS to 50 in three patients in each group who received etomidate 0.2 and 0.4 mg kg(-1), and in four patients who received 0.3 mg kg(-1). No awareness was recorded. MAP and HR increases following tracheal intubation were comparable between groups. CONCLUSIONS: Etomidate induction doses do not predict the time for BIS to decrease to 50 as this variable varies markedly following three etomidate dose regimen.

Adult↗
PubMed2003

[Diagnosis of ectopic mediastinal parathyroid adenomas: value of cardiac MRI].

Primary hyperparathyroidism is due to an adenoma in 85% of cases. In 10% of cases, the parathyroid adenoma may be in an ectopic location. Ten per cent of these ectopic adenomas are located in the mediastinum. Imaging modalities performed in persistent or recurrent hyperparathyroidism include ultrasound, MIBI scintigraphy, venous blood sampling, helical CT and MRI. The authors report 3 cases of ectopic adenoma located in the mediastinum, where pre-operative diagnosis was confirmed using cardiac MRI sequences.

Adenoma↗
PubMed2001

Prevention of postoperative pain after thyroid surgery: a double-blind randomized study of bilateral superficial cervical plexus blocks.

Local anesthetic infiltration may reduce postthyroidectomy pain. We performed a double-blinded, randomized, placebo-controlled trial to assess the analgesic efficacy of bilateral superficial cervical plexus blocks performed at the end of surgery. Ninety patients undergoing elective thyroid surgery by the same surgeon under general anesthesia were randomized to receive 20 mL isotonic sodium chloride or 20 mL bupivacaine 0.25% with 1:200,000 epinephrine. Postoperative pain was assessed every 4 h using an 11-point numeric rating scale (NRS-11). All patients received acetaminophen every 6 h. In addition, morphine was administered following a standardized protocol if the NRS-11 score was > or = 4. The main outcome variables were pain scores (NRS-11), the proportion of patients given morphine at any time during the 24-h period, and the amount of morphine administered. The Bupivacaine group had a smaller proportion of patients given morphine (66.0% vs 90.0%; P = 0.016), and lower initial median pain scores (P = 0.002). We conclude that bilateral superficial cervical plexus blocks significantly reduce pain intensity in the postoperative period after thyroid surgery but do not provide optimal pain relief alone.

Analgesics, Opioid↗
PubMed2001

[Metabolic differentiation of the human longus colli muscle].

The cervical muscles have a dual postural and dynamic function, in order to ensure both the stability and the motility of the cervical spine. The functional duality together with the complexity of the cervico-cephalic system render the study of the cervical muscles difficult, and their physiology is not fully understood in humans. This study has been carried out on ten samples from the m. longus colli, taken during a surgical procedure in patients aged between 36 to 62 years. The histological study combined enzyme histochemical (ATPases) and immunohistochemical techniques (using antibodies specific for the slow and the fast isoforms of the myosin heavy chains). Our results indicate that, in all cases, the m. longus colli is composed of muscle fibers with peripheral nuclei and with a relative dispersion in size. Histochemically, the type 1 and type 2 fibers express exclusively either the slow or the fast myosin heavy chain. From a quantitative point of view, the proportion of the slow fibers varies between extreme values of 30 and 73%; in addition, the dispersion in fiber size predominates on the fast type 2 fibers which are smaller than the slow type 1 fibers. Thus, most of the muscles that we have studied have histologically a slow predominance. This predominant expression of a slow phenotype in the m. longus colli corresponds to its important postural function, in addition to its phasic role during the flexion of the cervical spine.

Adult↗
PubMed2001

[Which adrenal incidentalomas are to be operated?].

AIM OF THE STUDY: The goal of this retrospective study was to recognize the incidence of adrenal tumors called incidentalomas, that are in fact symptomatic or hormone secreting tumors, to assess if the diagnostic criteria proposed in the literature are reliable for adrenal tumors found incidentally. PATIENTS AND METHOD: The records concerned 147 patients operated between April 1981 and December 2000 for an adrenal mass measuring 3 cm in diameter and larger on CT scan. Clinical and laboratory findings as well as hormone levels and imaging examinations (CT Scan, IRM, scintigraphy) were correlated with operative findings and results of histologic examinations. One hundred and three patients were operated by a traditional approach and forty four by videoendoscopic techniques. RESULTS: In 41 patients (28%), the tumors had to be classified as false incidentalomas (group 1) postoperatively. In 106 patients (72%), the nature of tumor was non definite. In this group 2, there were ten malignant tumors, two pheochromocytomas and 94 benign lesions. Age of patient, size of tumor, increase in size over time and radiological appearance represent criteria that are not reliable to separate malignant from benign tumors. CONCLUSIONS: Tumors of indeterminated and non specific nature only should be classified as incidentalomas. Imaging techniques as well as other criteria of malignancy cannot be relied upon to separate benign from malignant tumors. The risk even small of cancer or pheochromocytoma leads us to recommend excision of tumors > or = 3 cm in radiological diameter. The videoendoscopic approach is a good alternative to open operation in centers with this special expertise.

Adenoma↗
PubMed1999

Unilateral neck exploration under local anesthesia: the approach of choice for asymptomatic primary hyperparathyroidism.

BACKGROUND: Conventional parathyroidectomy involves a bilateral neck exploration with the patient under general anesthesia with a thorough search for all parathyroid tissue. The purpose of this study was to assess the efficacy and safety of unilateral neck exploration under local anesthesia in patients with asymptomatic primary hyperparathyroidism (first-degree hyperparathyroidism). METHODS: Of 679 patients who underwent parathyroidectomy for first-degree hyperparathyroidism from July 1989 to June 1997, 230 asymptomatic patients underwent unilateral neck exploration under local anesthesia. Selection criteria for this approach included the successful identification of a solitary parathyroid adenoma on preoperative imaging, no thyroid disease, and no family history of multiple endocrine neoplasia. Intact parathyroid hormone levels were monitored during the operation. RESULTS: Total serum calcium levels were normal in 220 patients (96%) 3 to 6 months after surgery. Ten patients (4%) experienced persistent hypercalcemia, 8 of whom had multiple gland disease and 2 of whom had false-positive imaging. Two of these patients underwent bilateral neck exploration under general anesthesia and were cured, although 8 patients remained asymptomatic and were followed up non-operatively. The mean operating time was 30 minutes (range, 12-65 minutes). There were two complications (0.87%) including one wound hematoma and one transient recurrent laryngeal nerve palsy. CONCLUSIONS: Unilateral neck exploration under local anesthesia is an efficacious and safe approach to the treatment of first-degree hyperparathyroidism and should be considered in all patients with asymptomatic disease.

Adenoma↗
PubMed1999

[Elements for a cost/utility analysis of long term intravenous devices].

Three long-term intravenous infusion strategies were compared, namely an implantable port (IP), a tunneled central catheter (TCC), and repeated peripheral catheterization (RPC). A decision analysis model was used in which the sequence of decisions and their possible consequences was described as a decision tree for each of the three strategies. The likelihood of each event occurring was determined based on a literature review. Each event was assigned a cost and a utility. Direct medical costs for the society include the cost of the material, the cost of implantation and removal of the device in the operating room, and the cost of treating complications directly ascribable to the strategy used. Utility is a combination of efficacy (as evaluated based on the likelihood of use of the strategy for one year) and quality of life (as evaluated by experts). In the basic analysis, RPC was the most cost-saving method but had an adverse effect on quality of life (0.82). The cost of using IC or TCC for one year was higher, with the main contributors to the excess cost being the insertion procedure and the management of complications (primarily deep vein thrombosis and infection). Quality of life was better with IC (0.98) than with TCC (0.93). IC also had a higher cost-utility ratio (11,738 French francs [FF]) versus 17,393 FF). A one-way sensitivity comparison of IC and TCC showed that the only realistic change capable of reversing the order between these two methods was a decrease by one-third in the risk of infection with TCCs. This model, used here for the first time, establishes that IC is superior over TCC.

Catheterization↗
PubMed1997

[Role of selective venous catheterization with assay of parathormone 1-84 in the treatment of persistent hyperparathyroidism].

From March 1993 to October 1994, 12 patients operated for persistent hyperparathyroidism had preoperative catheterization of large cervical and mediastinal veins (CLCMV) with determination of serum concentration of intact parathyroid hormone. Other localization procedures included: ultrasonography (US, n = 9), computed tomography (CT, n = 8), magnetic resonance imaging (MRI, n = 5), and sestamibi radionuclide imaging (MIBI, n = 9). A (1-84 PTH) gradient of 1-84 PTH was demonstrated in all patients, localizing a lesion in the neck (n = 9) or in the mediastinum (n = 3). An adenoma was found in nine patients either in the neck (n = 6) or in the mediastinum (n = 3), and 2 patients had glandular hyperplasia. Two patients remained hypercalcemic despite the removal of parathyroid tissue during CLCMV-guided reexploration. An other patient underwent unsuccessful neck reexploration. The sensitivity of other procedures was lower: US: 22%, CT: 50%, MRI: 60%, and MIBI: 66.5%. After a median follow-up of 13 months, 9 patients were cured of their hyperparathyroidism (75%) and 3 had persistent hypercalcemia. Our results suggest that CLCMV with 1-84 PTH measurement is the most accurate localization procedure in persistent hyperparathyroidism.

Adult↗
PubMed1996

Absorbable Adams-DeWeese caval clip: an experimental study.

Adams-DeWeese caval clips have been shown to be effective in preventing pulmonary embolism. However, the use of Teflon clips constitutes a permanent solution for this transient risk. We tested an absorbable caval clip made of currently available synthetic biodegradable polymers in five female beagle dogs. The polymer used was PLA 96 containing 96% L lactic acid and 4% D lactic acid. After placement through a laparotomy, clips were routinely inspected and samples of the material were collected at regular intervals between 3 and 19 months postoperatively. The characteristics of absorption of PLA 96 in the retroperitoneal space were the same as those previously described in the literature. The clip retained its shape, rigidity, and effectiveness for 7 months. Complete degradation of the clip took between 18 and 19 months. Absorption did not cause a major inflammatory reaction and had no thrombogenic effect. Given the small number of animals studied, these results must be considered preliminary.

Animals↗
PubMed1996

Values of ultrasonography, sestamibi scintigraphy, and intraoperative measurement of 1-84 PTH for unilateral neck exploration of primary hyperparathyroidism.

Unilateral neck exploration (UNE) is a controversial approach to the treatment of primary hyperparathyroidism (PHP), and most surgeons favor bilateral neck exploration. The aim of this study was to assess the value of ultrasonography, sestamibi scintigraphy, and intraoperative measurement of urinary cyclic AMP (UcAMP) or 1-84 PTH in 200 patients undergoing unilateral neck exploration under local anesthesia. Conditions for UNE were (1) a presumed solitary adenoma detected by ultrasonography, (2) no thyroid disease, and (3) no family history of PHP or multiple endocrine neoplasia. Patient's consent was obtained for conversion to bilateral exploration according to surgical and biologic findings. Sensitivity of ultrasonography was 92.5%. Sestamibi scintigraphy, performed in 70 patients, was less sensitive than ultrasonography (80%). Persistent PHP was accurately detected by intraoperative measurement of UcAMP or 1-84 PTH in all cases. At follow-up, 96.0% of the patients were cured either after unilateral neck exploration only (90.5%), or after conversion into bilateral exploration. Ultrasonography and intraoperative measurement of 1-84 PTH allow unilateral neck exploration with excellent results in a selected group of patients with PHP.

Adenoma↗
PubMed1996

[Complications of two types of pancreatic anastomosis after pancreaticoduodenectomy].

The operative mortality rate after pancreaticoduodenectomy (PD) is 5% or less at major surgical centers and is generally related to pancreatic anastomosis complications. Recently, several authors have reported a low incidence of complications after PD using pancreaticogastrostomy. The aim of our work was to retrospectively study the operative complications of pancreaticogastrostomy (PG) and pancreaticojejeunostomy (PJ) after PD. Since 1989 we have performed 59 consecutive DP, in 33 male patients and 22 female patients, with a mean age of 56 +/- 12 years. We performed 43 PG and 16 PJ. In 42/59 cases, PD was performed for malignant disease. Pancreaticoduodenal resection was identical in both groups, with classical pancreatic transection performed at the level of the mesentericoportal axis. The overall mortality rate in this study was 5.08% (n = 3). It was 4.65% (n = 2) in the PG group and 6.25% (n = 1) in the PJ group. Operative complications were absent in 36 patients (24 PG, 12 PJ). The mean postoperative hospital stay was 17 +/- 6 days; 23 patients (19 PG, 4 PJ) presented one or several complications. 12 patients required re-exploration (10 PG, 2 PJ). Pancreatic fistula occurred in 8 patients (13.55%), 14% (n = 6) in the PG group and 12.5% (n = 2) in the PJ group. In each group, only one pancreatic fistula was re-explored. Seven patients (16%) in the PG group presented postoperative pancreatitis. Pancreatic fistula and postoperative pancreatitis occurred in a pancreas with a normal texture and non-dilated pancreatic duct in every case, with one exception (PJ). During long term follow-up, 18 patients died from cancer (12 PG, 6 PJ). In conclusion, this study suggests that PG does not decrease the pancreatic fistula or postoperative pancreatitis rates and that these complications are essentially related to pancreatic texture and pancreatic duct.

Adult↗