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J M Malinovsky

Publications and source records attributed to J M Malinovsky.

At least 19 recordsLinked to original sources
PubMed2005

[Anaesthesia and prostate surgery].

OBJECTIVES: To review the current data about anaesthetic management in prostate surgery with special regards on analysis and prevention of specific risks, appropriate anaesthetic procedure keeping with surgery and patient, recognition and treatment of adverse events. DATA SOURCES AND EXTRACTION: The Pubmed database was searched for articles (1990-2004) combined with references analysis of major articles on the field. DATA SYNTHESIS: It is strongly recommended to settle germfree urine in the preoperative period. The thromboembolic risk of radical retropubic prostatectomy for cancer parallels lower abdomen oncologic surgery and is prolonged. Preoperative evaluation of cardiovascular, respiratory, neurological and metabolic comorbidity is a source of prognostic information and an essential tool in the management of elderly patients with prostate disease. Extreme patient positioning applied in prostate surgery induces haemodynamic and respiratory changes and are associated with severe muscular and nervous injuries. The laparoscopic access for radical prostatectomy is a growing alternative to the open surgical procedure. Acute normovolaemic haemodilution is a consistent and cost-effective blood conservation strategy in reducing allogenic blood transfusion for radical retropubic prostatectomy. Whether open transvesical or transurethral prostatectomy for treatment of benign hypertrophy depends on the size of the gland: transurethral resection is safe up to 80 g. Intrathecal anaesthesia with a T9 cephalad spread of sensory block, produces adequate conditions for transurethral prostatectomy and allows a rapid diagnosis of irrigating fluid absorption syndrome. In spite of recommended preoperative antibiotic prophylaxis, bacteriemias are frequent during transurethral prostate resection.

Adenoma↗
PubMed2002

[Discitis after spinal anesthesia for transurethral resection of the prostate].

We described a case of discitis and meningitis following spinal anaesthesia for transurethral resection of the prostate. The patient received antibiotics for a month before surgery, because of Klebsiella prostatitis. Spinal anaesthesia was performed in L3-L4 interspace by using 22G Quincke needle. Bacteriaemia occurred during the first postoperative hours. Ten days after spinal anaesthesia, patient suffered from lumbar pain, exacerbated by vertebral percussion, and motor weakness within lower limb, which was marked on right side. MRI examination showed L3-L4 discitis with psoas abcess in regard, and epiduritis marked around L3 right spinal root. CSF examination confirmed meningitis but no bacteria was found. Antibiotics were administered over a 6 weeks period, and then patient discharged from hospital without neurological sequellae. Infectious discitis related to disk puncture during spinal anaesthesia and postoperative bacteriaemia was likely in our patient.

Aged↗
PubMed2000

Intrathecal anesthesia: ropivacaine versus bupivacaine.

We compared intrathecal ropivacaine to bupivacaine in patients scheduled for transurethral resection of bladder or prostate. Doses of ropivacaine and bupivacaine were chosen according to a 3:2 ratio found to be equipotent in orthopedic surgery. One hundred patients were randomly assigned to blindly receive either 10 mg of isobaric bupivacaine (0.2%, n = 50) or 15 mg of isobaric ropivacaine (0.3%, n = 50) over 30 s through a 27-gauge Quincke needle at the L2-3 level in the sitting position. Onset and offset times for sensory and motor blockades and mean arterial blood pressure were recorded. Pain at surgical site requiring supplemental analgesics was recorded. Cephalad spread of sensory blocks was higher with bupivacaine (median level, cold T(4) and pinprick T(7)) than with ropivacaine (cold T(6) and pinprick T(9)) (P<0.001). Eight patients in Group Ropivacaine received IV alfentanil (P<0.01). Onset time (mean +/- SD) to T(10) anesthesia and offset time at L2 were not different (bupivacaine = 13 +/-8 min, 127+/-41 min; ropivacaine = 11+/-7 min, 105+/-29 min). Complete motor blockade occurred in 43 patients with bupivacaine and in 41 patients with ropivacaine (not significant). Total duration of motor blockade was not different. No difference in hemodynamic effects was detected between groups. No patient reported back pain. We conclude that 15 mg of intrathecal ropivacaine provided similar motor and hemodynamic effects but less potent anesthesia than 10 mg of bupivacaine for endoscopic urological surgery.

Aged↗
PubMed2000

Intermittent androgen suppression in the treatment of metastatic prostate cancer.

BACKGROUND: To assess the feasibility of intermittent androgen suppression in patients with metastatic prostate cancer and to quantify the improvement in the quality of life. METHODS: Forty-three patients with M1 b prostate cancer were treated by intermittent hormonal deprivation using luteinizing hormone-releasing hormone (LHRH) analogue alone (n = 11), or associated with an antiandrogen (n = 32). The prospective nonrandomized study required an initial therapy period of 12 months with a stable biological response during 6 months (PSA, testosterone). Treatment was resumed when the serum PSA value recovered to 20 ng/ml, or when local failure or new bone metastasis occurred. The assessment of quality of life was carried out using the EORTC QLQ-C30. RESULTS: The mean follow-up time was 43.7 months. After the initial 12 months of androgen suppression, one patient with a minimal disease was off-therapy with a follow-up of 18 months. For the 42 other patients, the mean off-therapy period was 6.7 months. In the second therapy period (9-12 months), 7 patients were hormono-independent and died with a mean survival time of 27 months; 35 patients were responders. The mean off-therapy length in the second cycle was short (3.8 months). After this time, androgen suppression therapy was reintroduced permanently, but 10 patients were hormono-independent. No difference was observed in the EORTC QLQ-C30 between therapy and off-therapy periods, only a rapid decrease in adverse events due to the hormonal deprivation was reported in all cases during the off-therapy period. CONCLUSIONS: Intermittent androgen suppression in patients with M1 b prostate cancer could be associated with a significant period off-therapy in the first cycle (55.8%), and with a chance of second hormone response. But in the second cycle, the off-therapy period length was short and required a careful follow-up.

Aged↗
PubMed1999

A dose-response study of epidural liposomal bupivacaine in rabbits.

Liposomes are drug delivery systems used to prolong local effects of bupivacaine. We studied the relationships between motor and hemodynamic changes and epidural doses of plain bupivacaine (P) and liposomal bupivacaine (L) in rabbits equipped with chronical lumbar epidural and femoral arterial catheters. Liposomal (phosphatidylcholine-cholesterol) suspensions contained 20 mg ml-1 of lipid, and different doses of bupivacaine (Lipo 7.5=7.5-; Lipo 3.7=3. 75-; Lipo 2.5=2.5-; Lipo 1.2=1.25-; and Lipo 0.7=0.65-mg of bupivacaine per ml). Forty rabbits were randomly assigned to five groups to receive epidural anesthesia (1 ml) as follows: Groups I to V received 0.65 to 7.5 mg of bupivacaine as P then as L. Release rate of bupivacaine from liposome was significantly slower using Lipo 3.7 than after Lipo 2.5 (Td was 3.9 h and 1.7 h respectively). Increasing the doses of L and P resulted in faster onset time for complete motor blockade and in a prolonged duration of motor effects. Liposomal formulation appears to be a powerful delivery system to prolong the motor effects of bupivacaine since E50 was lower and Emax higher than after the use of plain solution (E50 4.49+/-1.81 mg and Emax 152+/-40 min for P; and E50 2.61+/-0.23 mg and Emax 202+/-9 min for L). Hemodynamic changes were linearly related to doses of bupivacaine injected. The best bupivacaine-to-lipid ratio to prolong motor effects using our model was 3.75 mg and 20.0 mg respectively (Lipo 3.7).

Anesthesia, Epidural↗
PubMed1999

The age-related effects of epidural lidocaine, with and without epinephrine, on spinal cord blood flow in anesthetized rabbits.

UNLABELLED: The effect of epidural or spinal epinephrine when added to local anesthetics on spinal cord blood flow (SCBF)are controversial. We evaluated the effects of epidural lidocaine, with or without epinephrine, on spinal cord blood flow in young and adult rabbits receiving 2% plain lidocaine, 2% lidocaine with epinephrine (1:200,000), or saline epidurally. Colored microspheres were injected through the left ventricle 10 min before and 7.5 and 30 min after epidural injection. The organs (brain, heart, kidneys, and the L6-7 segment of the spinal cord) were analyzed for regional blood flow determination. A significant decrease in mean arterial pressure was observed after the administration of lidocaine, with or without epinephrine, in both adult and young animals compared with saline. SCBF did not change over time in adult rabbits. Conversely, a significant decrease in SCBF was observed in the two groups of young rabbits receiving lidocaine. This decrease correlated with the decrease in mean arterial pressure but did not correlate with the use of epinephrine. We conclude that any reduction in blood pressure occurring in pediatric patients receiving a combined epidural-general anesthetic may result in decreased SCBF. IMPLICATIONS: In young rabbits, any decrease in blood pressure was followed by a decrease in spinal cord blood flow, a decrease that did not correlate to the use of epinephrine and was not observed in adult animals. These data suggest that blood pressure should be monitored closely to promptly treat any decrease in blood pressure when combined epidural-general anesthesia is used in children.

Aging↗
PubMed1999

Intrathecal bupivacaine in humans: influence of volume and baricity of solutions.

BACKGROUND: The effects of volume and baricity of spinal bupivacaine on block onset, height, duration, and hemodynamics were studied. METHODS: Ninety patients undergoing endoscopic urologic procedures were randomized to receive 10 mg of intrathecal bupivacaine at L2-L3 level in sitting position. In the operating room, commercial products were diluted as needed with NaCl 0.9% to obtain isobaric solutions (density, 1.005-1.008) or with NaC 10.9% and glucose 30% to obtain hyperbaric solutions (density, 1.031-1.037) of 2, 5, or 10 ml (six groups of 15 patients each). Three minutes after spinal injection the patients were placed in lithotomy position. Sensory blockade was assessed using pinprick and cold sensation tests, and motor blockade was assessed using a four-point scale. RESULTS: Onset times to maximal cephalad spread of spinal blockade were similar with isobaric and hyperbaric solutions. A greater maximal cephalad spread of anesthesia was obtained with diluted isobaric bupivacaine but was not associated with more hypotension. Volume had no effect on cephalad extent of anesthesia with hyperbaric bupivacaine. Times for regression of anesthesia to L2 and offset of motor block were longer with isobaric than with hyperbaric solutions of bupivacaine. The intensity of motor blockade was decreased with diluted hyperbaric bupivacaine. No patient reported back pain. CONCLUSION: In this study, volume had no significant influence on either cephalad spread or duration of sensory blockade for either isobaric or hyperbaric bupivacaine. Time for offset of anesthesia was shorter with hyperbaric bupivacaine compared with isobaric solutions.

Aged↗
PubMed1999

Cerebrospinal fluid bioavailability and pharmacokinetics of bupivacaine and lidocaine after intrathecal and epidural administrations in rabbits using microdialysis.

The aim of this work was to study the cerebrospinal fluid (CSF) bioavailability and pharmacokinetics of bupivacaine (BUP) and lidocaine (LID) administered separately in rabbits using microdialysis with retrodialysis calibration. Microdialysis probe and catheters were inserted under control of the view in the intrathecal or epidural spaces. The epidural disposition of BUP and LID after epidural administration of low (0.69 microM) and high (6.9 microM) doses was studied. Then, the intrathecal and plasma dispositions after separate intrathecal (0.2 microM) and epidural administration (6.9 microM) were investigated. The CSF binding of BUP and LID was linear in a range from 50 to 500 micrograms/ml, and the mean unbound CSF fraction at a concentration of 100 micrograms/ml was 39. 3 +/- 2.3% for BUP and 75.8 +/- 7.7% for LID. Epidural and intrathecal disposition of BUP and LID showed a biexponential decline. After epidural administration, the CSF concentrations of BUP and LID were much higher than those in plasma. After intrathecal administration, the plasma concentrations were below the limit of quantitation. Although the absorption rate of BUP appeared higher than that of LID, the mean CSF bioavailability of epidural BUP and LID was 5.5 and 17.7%, respectively. The unexpectedly higher CSF bioavailability of LID, the less lipophilic drug, may result from the difference in the processes competing for drug epidural removal.

Anesthetics, Local↗
PubMed1998

In vitro and in vivo microdialysis calibration using retrodialysis for the study of the cerebrospinal distribution of bupivacaine.

Microdialysis coupled to HPLC was used to study the disposition of local anesthetics in the cerebrospinal fluid (CSF) because of the difficulty in sampling CSF. A retrodialysis method for the microdialysis calibration was investigated in vitro and in vivo. Calibration by retrodialysis was simultaneously validated through the use of the zero net flux method. Two local anesthetics (bupivacaine and ropivacaine), which differ structurally by only one methyl group, were respectively utilized as substance of interest and as internal standard. Different parameters were tested in vitro to compare the relative recovery (RR) of bupivacaine and the relative loss (RL) of ropivacaine. Several flow rates were tried to select an optimal in vivo flow rate (1 microliter/min). the RR and RL values were not influenced by the variation of bupivacaine concentration. A significant variability among different probes within a batch was established (RR ranging from 41.1-65.3%; RL ranging from 30.7-61.0%). The K-factor values, defined as RLropivacaine/RLbupivacaine, were calculated in vitro and in vivo. This ratio decreased in vivo but was constant (K in vitro = 1.06 +/- 0.04, K in vivo = 0.87 +/- 0.03). The extracellular tissue concentration of the compound of interest was again in vitro and no deterioration of probe during the in vivo experiment was found. After administration of bupivacaine in the epidural space of rabbits, plasma and microdialysis CSF samples were simultaneously collected. Plasma and CSF disposition of bupivacaine displayed different kinetics. The maximum CSF concentration of B averaged 394 +/- 170 micrograms ml-1 with a mean Tmax of 3.8 +/- 1.8 min. The maximum CSF concentration of B averaged 0.44 +/- 0.09 micrograms ml-1 with a mean Tmax occurring at 1 min. Microdialysis, combined with accurate calibration, should be a reliable technique to gain further insight in the spinal disposition of local anesthetics.

Anesthetics, Local↗
PubMed1998

The urodynamic effects of intravenous opioids and ketoprofen in humans.

UNLABELLED: We used a double-blind design to study urodynamic changes induced by mu-agonists (fentanyl, morphine), a partial mu-agonist antagonist (buprenorphine), a putative mu-antagonist, kappa-agonist (nalbuphine), and ketoprofen, an injectable nonsteroidal antiinflammatory drug. Men (20-55 yr old) were randomly assigned to receive one of the following i.v. before anesthesia for endoscopic extraction of a ureteral stone: 10 mg of morphine, 0.3 mg of buprenorphine, 0.35 mg of fentanyl, 20 mg of nalbuphine, 100 mg of ketoprofen, or 10 mL of 0.9% sodium chloride. The urodynamic study consisted of cystometry followed by urethral pressure profile. Measurements were taken before the i.v. infusion of drugs and 15 min thereafter. Statistical comparisons were performed by using analysis of variance with repeated measurements (P < 0.05). Ketoprofen and saline did not induce any urodynamic changes. Opioids altered bladder sensations, and the residual volume after voiding increased, except after morphine. Detrusor contraction decreased only after the administration of fentanyl and buprenorphine. Some patients could not micturate after receiving morphine, fentanyl, and buprenorphine. Compliance and urethral pressures did not change with any drug. This study suggests that ketoprofen and nalbuphine are useful analgesics in terms of their urodynamics. IMPLICATIONS: We compared the urodynamic effects of opioids and ketoprofen used as analgesics in surgical patients. In contrast to ketoprofen, opioids altered urodynamics. The opioid nalbuphine had no effect on detrusor contraction. This study suggests that ketoprofen and nalbuphine are useful analgesics in terms of their urodynamics.

Adult↗
PubMed1997

Midazolam for premedication in children: nasal vs. rectal administration.

The authors compared the acceptance and efficacy of rectal and nasal administration of midazolam (MDZ) for premedication. Ninety-five ASA I and II paediatric patients (8 months to 12 years) scheduled for elective surgery were randomly allocated to two groups. Group R received 0.3 mg kg-1 of rectal midazolam (in 5 mL saline). Group N received 0.2 mg kg-1 of nasal midazolam (5 mg ml-1). Both groups were divided in two subgroups according to age (group RA (< or = 6 years, n = 33), group RB (> 6 years, n = 18), group NA (< or = 6 years, n = 28), group NB (> 6 years, n = 16)). At the time of premedication, tolerance to the administration was confirmed. Twenty min after rectal or 10 min after nasal administration the quality of sedation was recorded. The nasal midazolam, in commonly used dosages, induced a sedation similar to that following rectal administration with a shorter delay of onset. Nasal administration was more often painful than rectal administration. Swallowing (nasal midazolam) and concerns about modesty (rectal midazolam) were more frequent in older children. Because of its poor tolerance, nasal premedication should be reversed for cases where there is no alternative. Rectal premedication should be avoided in older children.

Administration, Intranasal↗
PubMed1997

Neurotoxicological assessment after intracisternal injection of liposomal bupivacaine in rabbits.

UNLABELLED: Experiments were performed on rabbits randomly assigned to intracisternally receive 0.3 mL of plain bupivacaine 5 mg/mL, liposomal bupivacaine 5 mg/mL, bupivacaine-free liposomes, or isotonic phosphate-buffered saline. Mechanical ventilation was initiated or intravenous dopamine was infused when respiratory depression or hypotension occurred. Seven days after the injection, the whole spinal cord was removed and histopathologic characteristics were studied on transverse sections. All preparations were devoid of phosphatidylcholine hydrolysis or oxidation compounds. Solutions without bupivacaine produced transient irritative signs that required sedation in most rabbits. Despite the similar duration of respiratory depression in groups receiving liposomal or plain bupivacaine, liposomes produced significantly prolonged motor blockade (126 vs 70 min). Correction of hypotension after plain bupivacaine required a longer dopamine infusion and larger doses than after liposomal bupivacaine (28 vs 18 min and 74 vs 47 mg). Necrosis was observed in the cervical area of two rabbits (one in the liposomal bupivacaine group and another in the phosphate buffer group). No demyelinated areas were noted in spinal cord examinations. We conclude that liposomal bupivacaine leads to a less severe sympathetic block and to a prolonged motor block, whereas histologic changes are not significantly different among groups. IMPLICATIONS: Multilamellar liposomes containing bupivacaine administered intracisternally to rabbits produce spinal cord histopathologic changes not significantly different from those observed with plain bupivacaine. Sustained release of bupivacaine from liposomes is suggested by the prolonged motor blockade and the reduced severity of arterial hypotension. Use of these liposomes could prolong the local anesthetic effects of bupivacaine.

Anesthetics, Local↗
PubMed1996

[Neurotoxicity of intrathecally administrated agents].

Spinal anaesthetics can induce histopathologic lesions and regional haemodynamic alterations in the spinal cord. There are numerous causes of neurologic lesions, including direct trauma of the spinal cord and nerve roots during puncture or catheter insertion, compromised spinal cord perfusion and direct neurotoxic effect. Histopathologic lesions are localized either in meninges (meningitis or arachnoiditis) or in neuraxis (myelitis or axonal degeneration). Neurotoxicity can result from decrease in neuronal blood supply, elicited by high concentrations of the solutions, long duration exposure to local anaesthetics, and the use of adjuvants. They have been implicated in the occurrence of cauda equina syndrome after continuous spinal anaesthesia using hyperbaric solution of lidocaine and tetracaine given through small diameter catheters. Selective spinal analgesia is induced by spinal opioids without motor blockade except for meperidine. Complications occurred in patients after high doses of morphine, which were related to one of its metabolites, morphine-3-glucuronide. Preservative-free opioid solutions are to be preferred for spinal anaesthesia. There is no report of neurotoxicity neither in animal studies, nor in humans, using spinal clonidine. In order to reduce the incidence of neurotoxicity, some safety rules should be followed. The lowest efficient dose of local anaesthetics must be given. Incomplete blockade should not necessarily lead to a reinjection. Large volume of hyperbaric lidocaine or repeated injections of such solutions must be avoided as well as preservative-containing solutions. The administration of new compounds by the spinal route must be supported by data of spinal neuropharmacology and the lack of neurotoxicity must have been previously checked with animal studies.

Analgesics, Opioid↗
PubMed1996

Ketamine and norketamine plasma concentrations after i.v., nasal and rectal administration in children.

It has been suggested that nasal administration of ketamine may be used to induce anaesthesia in paediatric patients. We have examined the pharmacokinetics of ketamine and norketamine after nasal administration compared with rectal and i.v. administration in young children. During halothane anaesthesia, 32 children, aged 2-9 yr, weight 10-30 kg, were allocated randomly to receive ketamine 3 mg kg-1 nasally (group IN3) or ketamine 9 mg kg-1 nasally (group IN9); ketamine 9 mg kg-1 rectally (group IR9); or ketamine 3 mg kg-1 i.v. (group IV3). Venous blood samples were obtained before and up to 360 min after administration of ketamine. Plasma concentrations of ketamine and norketamine were measured by gas liquid chromatography. Statistical comparisons were performed using ANOVA and the Kruskall-Wallis test, with P < 0.05 as significant. Mean plasma concentrations of ketamine peaked at 496 ng ml-1 in group IN3 within 20 min, 2104 ng ml-1 in group IN9 within 21 min, and 632 ng ml-1 in group IR9 within 42 min. Plasma concentrations of norketamine peaked at approximately 120 min after nasal ketamine, but appeared more rapidly after rectal administration of ketamine and were always higher than ketamine concentrations in the same situation. Calculated bioavailability was 0.50 in groups IN3 and IN9 and 0.25 in group IR9. We conclude that nasal administration of low doses of ketamine produced plasma concentrations associated with analgesia, but using high doses via the nasal route produced high plasma concentrations of ketamine similar to those that induce anaesthesia. However, the large volume of ketamine required was partly swallowed and led to an unacceptable variability of effect that precludes this route for induction of anaesthesia.

Administration, Intranasal↗