Pleuropulmonary blastoma in an adult: an initial case report

BACKGROUND

Pleuropulmonary blastoma (PPB) is a unique dysontogenetic neoplasm of childhood. Its primitive, sarcomatous features are analogous to those of other dysembryonic or dysontogenetic tumors, such as Wilms tumor, hepatoblastoma, neuroblastoma, and embryonal rhabdomyosarcoma. PPB typically presents in young children, most younger than 5 years, as a pulmonary and/or pleural-based tumor with cystic, solid, or combined cystic and solid features. These neoplasms are characterized histologically by primitive mesenchymal or a mixture of primitive and sarcomatous components and generally have an unfavorable clinical outcome: death occurs within 1-2 years after diagnosis.

METHODS

Clinicopathologic and radiographic findings of a man age 36 years with a cystic and solid mass in the left hemithorax were reviewed and compared with previously studied cases of PPB.

RESULTS

Pathologic examination of the mass revealed a cystic and solid neoplasm composed of malignant mesenchymal cells that were immunoreactive for vimentin and muscle specific actin and focally for desmin. The architectural and cytologic appearances as well as the immunohistochemical profile were those of type II PPB.

CONCLUSIONS

To the authors' knowledge, all previously reported cases of PPB occurred in children age 12 years or younger. They believe that this case represents the first occurrence of PPB in an adult and documents the finding that, although it is uncommon, adults can develop primitive neoplasms that are usually associated with the pediatric population. In addition, the clinicopathologic features observed in the authors' adult patient were consistent with their experience with this tumor type in children. The patient died less than 1 year after diagnosis.

Directional binding of HMG-I(Y) on four-way junction DNA and the molecular basis for competitive binding with HMG-1 and histone H1

Histone H1, HMG-1 and HMG-I(Y) are mammalian nuclear proteins possessing distinctive DNA-binding domain structures that share the common property of preferentially binding to four-way junction (4H) DNA, an in vitro mimic of the in vivo genetic recombination intermediate known as the Holliday junction. Nevertheless, these three proteins bind to 4H DNA in vitro with very different affinities and in a mutually exclusive manner. To investigate the molecular basis for these distinctive binding characteristics, we employed base pair resolution hydroxyl radical footprinting to determine the precise sites of nucleotide interactions of both HMG-1 and histone H1 on 4H DNA and compared these contacts with those previously described for HMG-I(Y) on the same substrate. Each of these proteins had a unique binding pattern on 4H DNA and yet shared certain common nucleotide contacts on the arms of the 4H DNA molecule near the branch point. Both the HMG-I(Y) and HMG-1 proteins made specific contacts across the 4H DNA branch point, as well as interacting at discrete sites on the arms, whereas the globular domain of histone H1 bound exclusively to the arms of the 4H DNA substrate without contacting nucleotides at the crossover region. Experiments employing the chemical cleavage reagent 1, 10-orthophenanthroline copper(II) attached to the C-terminal end of a site-specifically mutagenized HMG-I(Y) protein molecule demonstrated that this protein binds to 4H DNA in a distinctly polar, direction-specific manner. Together these results provide an attractive molecular explanation for the observed mutually exclusive 4H DNA-binding characteristics of these proteins and also allow for critical assessment of proposed models for their interaction with 4H DNA substrates. The results also have important implications concerning the possible in vivo roles of HMG-I(Y), histone H1 and HMG-1 in biological processes such as genetic recombination and retroviral integration.

Safety of radiographic imaging during pregnancy

Maternal illness during pregnancy is not uncommon and sometimes requires radiographic imaging for proper diagnosis and treatment. The patient and her physician may be concerned about potential harm to the fetus from radiation exposure. In reality, however, the risks to the developing fetus are quite small. The accepted cumulative dose of ionizing radiation during pregnancy is 5 rad, and no single diagnostic study exceeds this maximum. For example, the amount of exposure to the fetus from a two-view chest x-ray of the mother is only 0.00007 rad. The most sensitive time period for central nervous system teratogenesis is between 10 and 17 weeks of gestation. Nonurgent radiologic testing should be avoided during this time. Rare consequences of prenatal radiation exposure include a slight increase in the incidence of childhood leukemia and, possibly, a very small change in the frequency of genetic mutations. Such exposure is not an indication for pregnancy termination. Appropriate counseling of patients before radiologic studies are performed is critical.

Good outcomes of open pelvic fractures

While pelvic fractures are common injuries, those which communicate with an open wound are much less commonly encountered. These injuries have been associated with high morbidity and mortality in previous studies. We investigated our experience with open pelvic fractures retrospectively over a 79-month period. A total of 17 patients were identified, representing 2.7% of all pelvic fractures seen during this time period. There were no fatalities among the 15 patients who were not in cardiac arrest on arrival. Associated injuries were present in all patients. Functional outcome was good in eight patients and fair in seven. Although open pelvic fractures are severe injuries, survival in our study was 100% in those not arriving in cardiac arrest.

Eye injuries in patients with major trauma

BACKGROUND

A study was performed to determine the type and frequency of ocular injuries in patients with major trauma.

METHODS

All patients with ocular and adnexal injuries (n = 178) among 1,119 patients admitted with major trauma (Injury Severity Score >15) to the Royal Prince Alfred Hospital from July 1990 to December 1997 were analyzed.

RESULTS

Sixteen percent of the major trauma cohort had ocular or orbital trauma. Fifty-five percent of patients with injuries involving the face had ocular or orbital injuries. A range of ocular injuries was seen. Analysis of the major trauma cohort showed that motor vehicle drivers, orbital and base of skull fractures, eyelid lacerations, and superficial eye injuries were strongly associated with vision-threatening injury.

CONCLUSION

Patients with major trauma and facial injuries have a high risk of vision-threatening injury. Patients with orbital fractures, base of skull fracture, eyelid lacerations, and superficial eye injuries should be assessed by an ophthalmologist as part of the early management of their trauma to determine whether an ocular injury is present.

Bile duct epithelial cells exposed to alpha-naphthylisothiocyanate produce a factor that causes neutrophil-dependent hepatocellular injury in vitro

The acute hepatotoxicity induced by alpha-naphthylisothiocyanate (ANIT) in rats is manifested as neutrophil-dependent necrosis of bile duct epithelial cells (BDECs) and hepatic parenchymal cells. This hepatotoxicity mirrors that of drug-induced cholangiolitic hepatitis in humans. Since BDECs are primary targets of ANIT-induced toxicity, we hypothesized that after exposure to ANIT, BDECs produce a factor(s) that causes neutrophil chemotaxis and neutrophil-dependent hepatocellular injury. To test this hypothesis BDECs were isolated from male Sprague Dawley rats and incubated with ANIT (6.25, 12.5, 25, or 50 microM) or vehicle for 24 h. The conditioned medium (CM) was collected and placed in the bottom chamber of a two-chambered chemotaxis system, while isolated neutrophils were placed in the top chamber. Chemotaxis was indicated by neutrophil migration through a membrane to the bottom chamber. CM from BDECs exposed to each concentration of ANIT was chemotactic, whereas CM from vehicle-treated BDECs was not. ANIT alone caused a modest degree of chemotaxis at 50 microM. The conditioned media were added to isolated hepatocytes or to hepatocyte-neutrophil cocultures and incubated for 24 h. Hepatocyte toxicity was indicated by alanine aminotransferase release into the culture medium. CM from vehicle-treated BDECs did not cause hepatocyte killing in either hepatocyte-neutrophil cocultures or hepatocyte cultures. In contrast, the addition of CM from ANIT-treated BDECs (CM-BDEC-A) to hepatocyte-neutrophil cocultures resulted in hepatocyte killing. The same CM was not cytotoxic to hepatocyte cultures devoid of neutrophils. The hepatocyte killing could not be explained by residual ANIT in the CM, which was below the limit of detection (< or = 0.5 microM). The addition of antiproteases afforded protection against neutrophil-dependent hepatocellular injury induced by CM-BDEC-A. These results indicate that ANIT causes BDECs to release a factor(s) that attracts neutrophils and stimulates them to injure hepatocytes in vitro.

Low-stage carcinoma of the male breast. A histologic, immunohistochemical, and flow cytometric comparison with localized female breast carcinoma

Male breast carcinoma (MBC) accounts for only 1% of total mammary carcinomas. Controversy exists about whether MBC differs clinically and pathologically from female breast carcinoma (FBC). We compared 10 archival cases with 75 stage-matched FBCs. Clinical data, histologic details, immunostains for mammary lineage markers, and results of several putative "prognostic" analyses were addressed, including DNA ploidy and expression of c-erbB-2 (neu) oncoprotein and p53 protein. Cumulative literature data on 2,530 MBCs were contrasted with information from 135 institutional cases of FBC. A statistically significant difference in grade 3 lesions at low stage persisted when MBCs of all stages were compared with similar FBCs. For stages I and IIA, 5-year survival was 60% and 86% for MBCs and FBCs, respectively (also statistically significant). This difference disappeared when all stages were compared. A similar number of MBCs and FBCs, regardless of stage, demonstrated DNA aneuploidy with or without synthesis of S-100 protein, gross cystic disease fluid protein-15, c-erbB-2 protein, and p53 protein. Hormone receptor positivity was more common in MBC than in FBC at high tumor stages. Low-stage MBC and FBC differ biologically; MBCs tend to manifest at a higher grade with lessened 5-year survival. However, aside from distinctions in hormone receptor proteins, broader comparison of MBC and FBC at stages IIB and higher shows no significant differences in 5-year survival or expression of breast cancer-associated gene products.

Severe sepsis caused by Mobiluncus curtisii subsp. curtisii in a previously healthy female: case report and review

We present the case of a 54-year-old female with life-threatening septicaemia due to Mobiluncus curtisii subsp. curtisii. Her admission was complicated by septic shock, renal failure, disseminated intravascular coagulation, the adult respiratory distress syndrome and spontaneous splenic rupture. The patient survived with full intensive care support and intravenous ceftriaxone. Extra-genital infection with Mobiluncus species is rarely diagnosed and has been confined to breast abscesses and non-life-threatening bacteraemia. A review of extra-genital infections with Mobiluncus species is presented.

Cytotoxicity of naphthylisothiocyanates in rat hepatocyte-neutrophil cocultures

1-Naphthylisothiocyanate (ANIT) produces cholangiolitic hepatitis in rats. This injury is characterized by periportal bile duct and hepatic parenchymal cell necrosis with inflammatory cell involvement. In contrast, 2-naphthylisothiocyanate (BNIT) does not induce cholangiolitic hepatitis. The mechanism(s) involved in ANIT-induced hepatic injury remain to be elucidated. To investigate this difference in toxicity further, we examined the cytotoxicity of ANIT and BNIT in primary rat hepatocyte cultures. Since neutrophils (PMNs) are required for the development of ANIT-induced cholangiolitic hepatitis in vivo, we also examined the potential for PMNs to modulate ANIT and BNIT cytotoxicity in rat hepatocyte-PMN cocultures. Both ANIT and BNIT injured rat hepatocytes within the range of concentrations examined (0-100 microM); however, BNIT was more potent. The presence of PMNs did not significantly influence the hepatocellular injury produced by either naphthylisothiocyanate (NIT). In an attempt to clarify the disparity between these results in vitro and observations reported in vivo, we examined, in hepatocyte PMN cocultures, the cytotoxic potential of bile collected from NIT-treated rats. Bile from BNIT-treated rats was markedly more cytotoxic to hepatocytes than was bile from ANIT-treated rats. As was observed in earlier experiments, the inclusion of PMNs had no effect on the hepatocellular toxicity of bile from NIT-treated rats. These findings prompted evaluation of the effect of NITs on rat PMNs. ANIT (1 and 10 microM) had no effect on phorbal myristate acetate (PMA)-induced superoxide production by PMNs, whereas BNIT (1 and 10 microM) markedly inhibited PMA-induced superoxide production. In contrast, ANIT and BNIT were equally effective at inhibiting f-met-leu-phe (fMLP)-induced PMN degranulation (beta-glucuronidase release). Altogether, the relative NIT toxicity observed in hepatocyte primary cultures is contrary to reports of hepatotoxic potential of these NITs in vivo. The PMN-dependence of ANIT hepatotoxicity in vivo was not reproduced in hepatocyte-PMN cocultures exposed to ANIT, suggesting that the PMN dependence in vivo involves factors not present in hepatocyte PMN cocultures. The greater PMN inhibitory effect of BNIT may, in part, underlie its inability to elicit the PMN-dependent liver injury in vivo that characterizes ANIT-induced cholangiolitic hepatitis.

Gynecology case challenge--persistent amenorrhea postpartum

A 32-year-old woman does not resume menses even more than a year after the birth of her third child. How would you assess and treat this problem?

Office management of Bartholin gland cysts and abscesses

Bartholin gland cysts and abscesses are common problems in women of reproductive age. Although the cysts are usually asymptomatic, they may become enlarged or infected and cause significant pain. Often the clinician is tempted simply to lance the cyst or abscess, since this technique can be effective for other common abscesses. However, simple lancing of a Bartholin gland cyst or abscess may result in recurrence. More effective treatment methods include use of a Word catheter and marsupialization, both of which can be performed in the office.

Alpha-naphthylisothiocyanate causes neutrophils to release factors that are cytotoxic to hepatocytes

Administration of alpha-naphthylisothiocyanate (ANIT) to rats causes acute liver injury characterized in part by hepatocellular damage and marked neutrophil infiltration, effects that resemble drug-induced cholangiolitic hepatitis in people. ANIT-induced liver injury is neutrophil dependent. Moreover, ANIT can activate neutrophils in vitro. Since neutrophil-derived proteases can mediate hepatocellular killing, we hypothesized that ANIT stimulates neutrophils to release proteolytic enzymes that are cytotoxic to hepatic parenchymal cells. To test this hypothesis, neutrophils were isolated from Sprague-Dawley rats and incubated with ANIT for 6-24 h. ANIT (6-50 microM) was not toxic to neutrophils as indicated by the lack of lactate dehydrogenase release into the incubation medium. The conditioned medium from ANIT-treated neutrophils (ANCM) was collected, centrifuged, added to isolated hepatocytes, and incubated for 8, 16, or 24 h. Conditioned medium collected from neutrophils exposed to 25 or 50 microM ANIT for 16-24 h caused hepatocellular damage as indicated by the release of alanine aminotransferase into the culture medium. The concentration of ANIT in ANCM was nondetectable (0.5 microM). Analysis of ANCM indicated the presence of both cathepsin G and elastase activities. Inhibitors of these enzymes afforded protection against ANCM-induced hepatocellular injury. These results indicate that ANIT causes neutrophils to release toxic proteases which cause hepatocellular damage in vitro.

A comparison of the effect of intrathecal and extradural fentanyl on gastric emptying in laboring women

We studied gastric emptying, using acetaminophen absorption, in 105 women in labor divided into three equal groups of 35 each, after intrathecal (i.t.) (25 micrograms, Group S) or extradural (50 micrograms, Group E) fentanyl in combination with bupivacaine and compared with a control group (Group C) receiving extradural bupivacaine only. The time to maximal acetaminophen concentration (tCamax), maximal acetaminophen concentration (Camax), and areas under the acetaminophen concentration-time curve at 90 and 120 min (AUC90 and AUC120, respectively) were determined. Median (range) tCamax values were 120 (15-180), 82.5 (15-180), and 90 (15-180) min in Groups S, E, and C, respectively (P < 0.05). Mean +/- SD Camax was 13.4 +/- 8.82, 17.9 +/- 8.06, and 15.0 +/- 6.22 micrograms/mL in Groups S, E, and C, respectively (P < 0.05). Mean +/- SD AUC90 and AUC120 were also significantly smaller in Group S than in the other two groups (430 +/- 616, 736 +/- 504, and 672 +/- 453; and 649 +/- 592, 1063 +/- 627, and 1053 +/- 616 micrograms.mL-1.min-1 in Groups S, E, and C, respectively). We conclude that the administration of fentanyl 25 micrograms i.t. delays gastric emptying in labor compared with both extradural fentanyl 50 micrograms with bupivacaine and extradural bupivacaine alone.

IMPLICATIONS

We examined emptying of the stomach in women in labor after administration of analgesics by the spinal or the epidural route. We observed that the analgesic, fentanyl, administered by the spinal route, although relieving pain rapidly, may delay emptying of the stomach. In theory, delayed gastric emptying may increase the chance of vomiting and aspiration of gastric contents.

Competition between HMG-I(Y), HMG-1 and histone H1 on four-way junction DNA

High mobility group proteins HMG-I(Y) and HMG-1, as well as histone H1, all share the common property of binding to four-way junction DNA (4H), a synthetic substrate commonly used to study proteins involved in recognizing and resolving Holliday-type junctions formed during in vivo genetic recombination events. The structure of 4H has also been hypothesized to mimic the DNA crossovers occurring at, or near, the entrance and exit sites on the nucleosome. Furthermore, upon binding to either duplex DNA or chromatin, all three of these nuclear proteins share the ability to significantly alter the structure of bound substrates. In order to further elucidate their substrate binding abilities, electrophoretic mobility shift assays were employed to investigate the relative binding capabilities of HMG-I(Y), HMG-1 and H1 to 4H in vitro. Data indicate a definite hierarchy of binding preference by these proteins for 4H, with HMG-I(Y) having the highest affinity (Kd approximately 6.5 nM) when compared with either H1 (Kd approximately 16 nM) or HMG-1 (Kd approximately 80 nM). Competition/titration assays demonstrated that all three proteins bind most tightly to the same site on 4H. Hydroxyl radical footprinting identified the strongest site for binding of HMG-I(Y), and presumably for the other proteins as well, to be at the center of 4H. Together these in vitro results demonstrate that HMG-I(Y) and H1 are co-dominant over HMG-1 for binding to the central crossover region of 4H and suggest that in vivo both of these proteins may exert a dominant effect over HMG-1 in recognizing and binding to altered DNA structures, such as Holliday junctions, that have conformations similar to 4H.

Endometrial cancer in relation to intra-uterine device use

Data from a population-based case-control study were used to evaluate the risk of endometrial cancer among women who have used an intra-uterine device (IUD). Incident cases were identified between 1985 and 1991 among women aged 45-74 years who were residents of one of 3 counties in Washington State. Controls were selected by random digit dialing, and both groups of subjects received an in-person detailed interview. In this study population, women who had ever used an IUD were estimated to have a risk of endometrial cancer that was 0.61 times that of other women (95% CI 0.41-0.89). The reduction in cancer risk was not found to be dependent on duration of IUD use. There was a suggestion that women who had used intra-uterine contraception relatively late in reproductive life experienced a greater reduction in risk than those whose use was more distant or at a younger age. The relative risk among the small number of women who were currently using an IUD was 0.49 (95% CI 0.12-2.80). These results apply to the use of inert and copper IUDs as there was no use of progestin-releasing IUDs among women in the study population. The data from this and several other studies of the question support the hypothesis that use of an IUD has a favorable effect on the subsequent risk of endometrial cancer. The reason(s) for such a reduced risk is unclear.

Low dose epidural bupivacaine/fentanyl infusion does not mask uterine rupture

A patient is described in whom the symptoms and signs of uterine rupture were not masked by combined spinal epidural analgesia with an epidural infusion of 0.1% bupivacaine and 1.5 microg ml(-l) fentanyl. Early recognition of the dehiscence of a previous caesarean section scar resulted in an excellent neonatal and maternal outcome.

A chi-square automatic interaction detection (CHAID) analysis of factors determining trauma outcomes

OBJECTIVE

Analysis of variables predictive of trauma outcome by the CHAID (chi-square automatic interaction detection) statistical program.

DESIGN

Retrospective analysis of a prospectively maintained trauma database.

METHODS

The study group consisted of 607 primary ambulance retrievals to Royal Prince Alfred Hospital, Sydney, for the period of 6 fiscal years (1990-1996) with major injury (Injury Severity Score > 15).

MAIN RESULTS

The overall mortality fell from 26.6 to 16% (chi 2 test = 14.7, p = 0.01) during the study period. The emergency room Glasgow Coma Scale (GCS) score (preresuscitation) was the strongest predictor of death or survival. CHAID segmented the study group into three categories based on GCS scores (¿3¿, ¿4-12¿, and ¿13-15¿), each with significantly different outcome predictability. The mortality rate in those with a GCS score of 3 (n = 89) was 67%. Systolic blood pressure was the strongest predictor of outcome in this subset. The mortality in those with GCS score of 4-12 (n = 160) was 18%. Injury Severity Score was the strongest predictor in this subset. The mortality rate in those with GCS score of 13-15 was 5%. Age was the strongest predictor in this group.

CONCLUSION

The CHAID-generated flowchart has proved useful in this pilot study to analyze the interrelation between variables predictive of outcome in an Australian urban trauma population.

Respiratory effects of spinal anaesthesia for caesarean section

We report the changes observed in a number of pulmonary function tests performed on 36 patients undergoing Caesarean section under spinal anaesthesia. The tests comprised peak expiratory flow, forced expiratory volume in one second, forced vital capacity, forced expiratory volume in one second to forced vital capacity ratio and the maximal mid-expiratory flow. Significant changes occurred that are consistent with a restrictive ventilatory defect. These changes persisted for four hours after the induction of spinal anaesthesia. Administration of 35% oxygen by facemask failed to change significantly fetal umbilical vein pH or partial pressure of oxygen.

Competency-based learning in neonatology

An educational model integrating structured teaching with clinical experience, or clerkship, has been designed to enable students to learn the core knowledge, skills and attitudes necessary to care for the newborn. The programme is run for fifth year medical students as part of four, 9-week periods in Obstetrics and Gynaecology each year. A SCORPIO teaching session is held in week 1 to introduce students to the core competencies in the subject areas of newborn examination, breastfeeding, resuscitation, respiratory distress and anthropometry. Groups of four students rotate through each topic, which is conducted by a neonatologist or registrar in training. Eight problem-based learning sessions are held during weeks 2-9. Several students assess a clinical problem, identify learning issues and meet colleagues and a facilitator to share their learning experiences and resolve the problem. The clinical experience, or clerkship, is based in the neonatal nursery where 2-3 students spend a week consolidating their clinical and procedural skills. A study group was assessed at the end of the programme by an Objective Structured Clinical Examination (OSCE) and a Multiple Choice Questionnaire (MCQ). A control group did the same assessment in week 1. All students were asked to rate the educational value of the three learning methods on a 5-point Likert scale. The study group (n = 20) achieved a mean composite mark of 66% (SD 10%). This was significantly higher (P < 0.001) than that of the control group (n = 18), mean 45% (SD 7%). All students (100%) rated the educational value of SCORPIO as high or very high, and the comparative rating for problem-based learning and clerkship was 65%, respectively. The programme was enthusiastically received by the students and resulted in mastery of a range of core competencies necessary for care of the newborn.

Comparative pharmacology of cisatracurium (51W89), atracurium, and five isomers in cats

BACKGROUND

Atracurium has four chiral centers and the marketed product is a mixture of ten optical and geometric isomers. Six of the isomers were prepared and evaluated for neuromuscular blocking activity and autonomic effects in anesthetized cats. This study reports the comparative pharmacology of the six isomers and atracurium that led to the selection of one isomer, cisatracurium (Nimbex, 51W89) for clinical development.

METHODS

Purpose bred cats, anesthetized with alpha-chloralose (80 mg/kg) and pentobarbital sodium (7 mg/kg) administered intraperitoneally, were used in this study. Neuromuscular blocking effects were assessed from the effects on the tibialis anterior twitch evoked at 0.15 Hz. Inhibition of the autonomic nervous system was assessed from the effects on the nictitating membrane contraction, in response to preganglionic sympathetic nerve stimulation and the bradycardia/vasodepressor responses to vagal nerve stimulation. Cardiovascular effects and plasma histamine concentrations were determined after a bolus injection of cisatracurium or atracurium.

RESULTS

Like atracurium, all six isomers produced dose-dependent neuromuscular block (NMB). The calculated ED95NMB values varied approximately tenfold (43 +/- 2 microgram/kg -488 +/- 56 microgram/kg. The "R-series" isomers were more potent than the corresponding "S-series" isomers. With the exception of the S,Trans-S', Trans isomers, the NMB effects, i.e., onset times (range 2.6 +/- 0.2 min to 4.7 +/- 0.3 min) and total durations (range 9.9 +/- 1.4 min to 14 +/- 0.9 min), of the other five isomers were very similar to that atracurium. The former isomers had relatively short duration of action. The 25-75% recovery times after cisatracurium at 1 x ED95 (4.4 +/- 0.4 min), 4 x ED95 (4.5 +/- 0.4 min), and continuous infusions lasting at least 60 min that maintained 95-99% NMB (4.8% +/- 0.4 min) indicated a noncumulative effect. The vagal ID50:NMB ED95 ratios for atracurium and the six isomers ranged from 2 to 27. The sympathetic ID25:NMB ED95 ranged from 2.7 to 60. Atracurium and all of the isomers, except cisatracurium, produced cardiovascular effects after intravenous bolus administration at large doses (700-4,800 micrograms/kg). In contrast to atracurium, there were no changes in plasma histamine concentrations associated with the administration of doses of cisatracurium equivalent to 60X the NMB ED95 (62 +/- 8 micrograms/kg).

CONCLUSIONS

Cisatracurium has neuromuscular blocking effects identical to those of atracurium, is more potent, and does not produce cardiovascular effects or increase plasma histamine concentrations.