Ondansetron to reduce neonatal opioid withdrawal severity a randomized clinical trial

OBJECTIVE

To determine if treatment with a 5-HT3 antagonist (ondansetron) reduces need for opioid therapy in infants at risk for neonatal opioid withdrawal syndrome (NOWS).

STUDY DESIGN

A multicenter, randomized, placebo controlled, double blind clinical trial of ninety (90) infants. The intervention arms were intravenous ondansetron or placebo during labor followed by a daily dose of ondansetron or placebo in infants for five days.

RESULTS

Twenty-two (49%) ondansetron-treated and 26 (63%) placebo-treated infants required pharmacologic treatment (p > 0.05). The Finnegan score was lower in the ondansetron-treated group (4.6 vs. 5.6, p = 0.02). A non-significant trend was noted for the duration of hospitalization. There was no difference in need for phenobarbital or clonidine therapy, or total dose of morphine in the first 15 days of NOWS treatment.

CONCLUSIONS

Ondansetron treatment reduced the severity of NOWS symptoms; and there was an indication that it could reduce the length of stay.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov NCT01965704.

Bupivacaine local anesthetic to decrease opioid requirements after radical cystectomy: Does formulation matter?

INTRODUCTION

Reduction of opioids is an important goal in the care of patients undergoing radical cystectomy (RC). Liposomal bupivacaine (LB) has been shown to be a safe and effective pain reliever in the immediate postoperative period and has been reported to reduce postoperative opioid requirements. Since the liposomal formulation is predicated on slow systemic absorption, the amount of bupivacaine administered is notably higher than that typically used with standard bupivacaine (SB) formulations. In addition, LB is costly, not universally available, and studies comparing this formulation to SB are lacking. We sought to determine if there is a difference in postoperative opioid requirements in patients who receive LB vs. high dose SB at the time of RC.

METHODS

In May 2019 we transitioned to administration of high-volume SB injected intraoperatively at the time of RC. This prospective cohort was compared to a historical cohort of patients who received injection of LB at the time of surgery. Primary endpoints included postsurgical opioid use measured in morphine equivalent dose (MED) and patient-reported Numeric Rating Scale (NRS) pain scores and length of stay. All patients were managed using principles of enhanced recovery after surgery (ERAS).

RESULTS

From May 2019 through August 2019, 28 patients underwent RC and met eligibility criteria to receive SB at the time of surgery. They were compared to a historical cohort of 34 patients who received LB between November 2017 and July 2018. There was no difference in MED exposure either in the postanesthesia care unit (SB 9.0 ± 8.9 MED vs. LB 6.5 ± 9.4 MED, P= 0.29) or during the remainder of the hospital stay (SB 36.8 ± 56.9 MED vs. LB 42.1 ± 102.5 MED, P= 0.81), no difference in NRS pain scores on postoperative day 1 (SB 2.6 ± 1.6 vs. LB 2.1 ± 1.7, P= 0.23), day 2 (SB 2.4 ± 1.8 vs. LB 1.9 ± 1.6, P= 0.19), or day 3 (SB 1.9 ± 1.8 vs. LB 1.7 ± 1.7, P= 0.69) and no difference in length of stay (SB 5.0 ± 1.7 days, LB 4.9 ± 3.3 days, P= 0.93). Subgroup analysis of open RC and robotic-assisted RC showed no significant difference in MED or pain scores between LB and SB patients.

CONCLUSIONS

Among patients undergoing RC under ERAS protocol there was no significant difference in postoperative opioid consumption, NRS pain scores, or length of stay among patients receiving SB compared to LB.

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Clinical and molecular characterization of individuals with recurrent genomic disorder at 10q22.3q23.2

The identification of genomic imbalances in young patients can affect medical management by allowing early intervention for developmental delay and by identifying patients at risk for unexpected medical complications. Using a 105K-feature oligonucleotide array, we identified a 7.25 Mb deletion at 10q22.3q23.2 in six unrelated patients. Deletions of this region have been described in individuals with cognitive and behavioral abnormalities, including autistic features, and may represent a recurring genetic syndrome. All four patients in this study for whom clinical information was available had mild dysmorphic features and three had developmental delay. Of note is the emerging clinical phenotype in these individuals with similar dysmorphic features such as macrocephaly, hypertelorism, and arachnodactyly, and neurodevelopmental delay that includes failure to thrive, hypotonia, and feeding difficulties in the neonatal period, and receptive and expressive language delay with global neurodevelopmental delay after the neonatal period. However, there is no pattern of abnormalities, craniofacial, behavioral, or otherwise, that would have aroused clinical suspicion of a specific syndrome. Finally, the patients' deletions encompass BMPR1A but not PTEN, and these patients may be at risk for colon cancer and should be referred for appropriate prophylactic care and surveillance. Of the two patients in this study who had colonoscopy following the array results, neither had polyps. Therefore, the magnitude of the increased risk for colon cancer is currently unknown.

Mapping Gender and Migration in Sociological Scholarship: Is It Segregation or Integration?

A review of the sociological research about gender and migration shows the substantial ways in which gender fundamentally organizes the social relations and structures influencing the causes and consequences of migration. Yet, although a significant sociological research has emerged on gender and migration in the last three decades, studies are not evenly distributed across the discipline. In this article, we map the recent intellectual history of gender and migration in the field of sociology and then systematically assess the extent to which studies on engendering migration have appeared in four widely read journals of sociology (American Journal of Sociology, American Sociological Review, Demography, and Social Forces). We follow with a discussion of these studies, and in our conclusions, we consider how future gender and migration scholarship in sociology might evolve more equitably.

Pharmacogenomics and drug development

It is generally anticipated that pharmacogenomic information will have a large impact on drug development and will facilitate individualized drug treatment. However, there has been relatively little quantitative modeling to assess how pharmacogenomic information could be best utilized in clinical practice. Using a quantitative model, this review demonstrates that efficacy is increased and toxicity is reduced when a genetically-guided dose adjustment strategy is utilized in a clinical trial. However, there is limited information available regarding the genetic variables affecting the disposition or mechanism of action of most commonly used medications. These genetic factors must be identified to enable pharmacogenomic testing to be routinely used in the clinic. A recently described murine haplotype-based computational genetic analysis method provides one strategy for identifying genetic factors regulating the pharmacokinetics and pharmacodynamics of commonly used medications.

Piritramide and alfentanil display similar respiratory depressant potency

BACKGROUND

The question whether some opioids exert less respiratory depression than others has not been answered conclusively. We applied pharmacokinetic/pharmacodynamic (PKPD) modeling to obtain an estimate of the C50 for the depression of CO2 elimination as a measure of the respiratory depressant potency of alfentanil and piritramide, two opioids with vastly different pharmacokinetics and apparent respiratory depressant action.

METHODS

Twenty-three patients received either alfentanil (2.3 microg x kg(-1) x min-1, 14 patients, as published previously) or piritramide (17.9 microg x kg(-1) x min(-1), nine patients) until significant respiratory depression occurred. Opioid pharmacokinetics and the arterial PCO2 (PaCO2) were determined from frequent arterial blood samples. An indirect response model accounting for the respiratory stimulation due to increasing PaCO2 was used to describe the PaCO2 data.

RESULTS

The following pharmacodynamic parameters were estimated with NONMEM [population means and interindividual variability (CV)]: k(elCO2) (elimination rate constant of CO2) 0.144 (-) min(-1), F (gain of the CO2 response) 4.0 (fixed according to literature values) (28%), C50 (both drugs) 61.3 microg l-1 (41%), k(eo alfentanil) 0.654 (-) min(-1) and k(eo piritramide) 0.023 (-) min(-1). Assigning separate C50 values for alfentanil and piritramide did not improve the fit compared with a model with the same C50.

CONCLUSION

Since the C50 values did not differ, both drugs are equally potent respiratory depressants. The apparently lower respiratory depressant effect of piritramide when compared with alfentanil is caused by slower equilibration between the plasma and the effect site. Generalizing our results and based on simulations we conclude that slowly equilibrating opioids like piritramide are intrinsically safer with regard to respiratory depression than rapidly equilibrating opioids like alfentanil.

Isoflurane antagonizes the capacity of flurothyl or 1,2-dichlorohexafluorocyclobutane to impair fear conditioning to context and tone

In animals, the conventional inhaled anesthetic, isoflurane, impairs learning fear to context and fear to tone, doing so at concentrations that produce amnesia in humans. Nonimmobilizers are inhaled compounds that do not produce immobility in response to noxious stimulation, nor do they decrease the requirement for conventional inhaled anesthetics. Like isoflurane, the nonimmobilizer 1,2-dichlorohexafluorocyclobutane (2N) impairs learning at concentrations less than those predicted from its lipophilicity to produce anesthesia. The capacity of the nonimmobilizer di-(2,2,2,-trifluoroethyl) ether (flurothyl) to affect learning and memory has not been studied. Both nonimmobilizers can cause convulsions. We hypothesized that if isoflurane, 2N, and flurothyl act by the same mechanism to impair learning and memory, their effects should be additive. We found that isoflurane, 2N, and flurothyl (each, alone) impaired learning fear to context and fear to tone in rats, with the nonimmobilizers doing so at concentrations less than those that cause convulsions. (Fear was defined by freezing [volitional immobility] in the presence of the conditioned stimulus [context or tone].) However, the combination of isoflurane and 2N or flurothyl produced an antagonistic rather than an additive effect on learning, a finding in conflict with our hypothesis. And flurothyl was no less potent than 2N (at least no less potent relative to the concentration of each that produced convulsions) in its capacity to impair learning. We conclude that conventional inhaled anesthetics and nonimmobilizers impair learning and memory by different mechanisms. The basis for this impairment remains unknown.

IMPLICATIONS

Conventional inhaled anesthetics and nonimmobilizers are antagonistic in their effects on learning and memory, and this finding suggests that they impair learning and memory, at least in part, by different mechanisms.

Non-steady state analysis of the pharmacokinetic interaction between propofol and remifentanil

BACKGROUND

The pharmacokinetics of both propofol and remifentanil have been described extensively. Although they are commonly administered together for clinical anesthesia, their pharmacokinetic interaction has not been investigated so far. The purpose of the current investigation was to elucidate the nature and extent of pharmacokinetic interactions between propofol and remifentanil.

METHODS

Twenty healthy volunteers aged 20-43 yr initially received either propofol or remifentanil alone in a stepwise incremental and decremental fashion a target controlled infusion. Thereafter, the respective second drug was infused to a fixed target concentration in the clinical range (0-4 microg/ml and 0-4 ng/ml for propofol and remifentanil, respectively) and the stepwise incremental pattern repeated. Frequent blood samples were drawn for up to 6 h for propofol and 40 min for remifentanil after the end of administration and assayed for the respective drug concentrations with gas chromatography-mass spectrometry. The time courses of the measured concentrations were fitted to standard compartmental models. Calculations were performed with NONMEM. After having established the individual population models for both drugs and an exploratory analysis for hypothesis generation, pharmacokinetic interaction was identified by including an interaction term into the population model and comparing the value of the objective function in the presence and absence of the respective term.

RESULTS

The concentration-time courses of propofol and remifentanil were described best by a three- and two-compartment model, respectively. In the concentration range examined, remifentanil does not alter propofol pharmacokinetics. Coadministration of propofol decreases the central volume of distribution and distributional clearance of remifentanil by 41% and elimination clearance by 15%. This effect was not concentration-dependent in the examined concentration range of propofol.

CONCLUSIONS

Coadministration of propofol decreases the bolus dose of remifentanil needed to achieve a certain plasma-effect compartment concentration but does not alter the respective maintenance infusion rates and recovery times to a clinically significant degree.

Pharmacokinetic study of FFP photochemically treated with amotosalen (S-59) and UV light compared to FFP in healthy volunteers anticoagulated with warfarin

BACKGROUND

To date, no clinical trials have characterized FFP infusion efficacy, and infusion still carries infectious risk. This single-blinded crossover study compared postinfusion kinetics of FVII in photochemically treated FFP to standard FFP.

STUDY DESIGN AND METHODS

Subjects donated plasma by apheresis. Half of the collected plasma was treated with the psoralen amotosalen hydrochloride (S-59) and UVA light, and half were prepared as standard plasma. Subjects received warfarin over 4 days to lower FVII levels. On Day 4, subjects received 1 L of either treated or standard FFP. After 2 weeks, subjects underwent a regimen identical to that with the other type of FFP.

RESULTS

After warfarin ingestion, the mean FVII concentration was 0.33 IU per mL. Both types of FFP exhibited comparable FVII kinetics, with a mean peak increment of 0.10 to 0.12 IU per mL occurring at the end of infusion. The effect disappeared after 8 hours.

DISCUSSION

Study data of warfarin-treated healthy volunteers demonstrate that psoralen plus UV-treated FFP provides an equivalent in vivo coagulation response to control plasma. A 1-L dose of FFP in adults may provide an initial increment of 0.10 IU per mL of FVII. In the absence of bleeding, FVII levels return to baseline after 8 hours.

Computer-controlled epidural infusion to targeted cerebrospinal fluid concentrations in humans. Clonidine

BACKGROUND

Pharmacokinetically designed infusions have been demonstrated to achieve rapidly and maintain desired concentrations of drug in plasma after intravenous administration. In this study we tested whether a similar approach, targeting concentrations in cerebrospinal fluid (CSF), could be used with epidural administration of the alpha 2-adrenergic analgesic clonidine.

METHODS

After institutional review board approval and informed consent had been obtained, seven healthy volunteers received a clonidine infusion through a lower lumbar epidural catheter. Infusion of clonidine (10 micrograms/ml) was controlled by the STANPUMP program for sequential 75-min periods to targeted CSF clonidine concentrations of 25, 50, 75, and 150 ng/ml. Before reprogramming to the next higher targeted concentration, mean arterial blood pressure and heart rate were measured; blood was obtained for clonidine and catecholamine assays; and visual analog score for sedation and pain to immersion of foot and hand in ice water were obtained. CSF was collected during infusion with an indwelling lumbar intrathecal catheter and was analyzed for clonidine, catecholamines, and acetylcholine.

RESULTS

CSF clonidine concentrations rapidly increased and were maintained at steady values with the stepped infusion, although observed concentrations were consistently greater than targeted. The relation between CSF clonidine concentration and analgesia in the foot was similar to that previously observed after epidural bolus administration. Clonidine also was associated with concentration-dependent sedation; decreased mean arterial blood pressure, heart rate, and CSF norepinephrine concentration; and increased CSF acetylcholine concentration.

CONCLUSIONS

This study suggests that pharmacokinetically designed infusions of drugs in the epidural space in humans can maintain steady concentrations of drug in CSF. In addition to providing a useful tool for investigation of mechanisms of action and drug interactions, this technique may improve analgesia and diminish side effects from epidurally administered analgesics.

Neurological soft signs. Their relationship to psychiatric disorder and intelligence in childhood and adolescence

Sixty-three male and 27 female adolescents known to have had neurological soft signs at the age of 7 years were compared with controls with no soft signs at age 7. Adolescents with early soft signs had significantly lower IQs and were more likely to have a psychiatric disorder characterized by anxiety, withdrawal, and depression. All the girls and 80% (12/15) of the boys with an anxiety-withdrawal diagnosis showed early soft signs. There was no relationship between early soft signs and attention deficit or conduct disorders. Examination of the relative contributions of anxiety at age 7, IQ, and social and family disadvantage to later diagnosis showed that most of the variance was accounted for by soft signs independently of IQ. Soft signs and anxious dependent behavior at age 7 were strongly predictive of persistent psychiatric disorder characterized by anxiety and withdrawal.

The mechanism of action of a single dose of methylprednisolone on acute inflammation in vivo

A model system for the study of inflammation in vivo has been developed using the 16-h polyvinyl sponge implant in the rat. This system allows for simultaneous measurement of in vivo chemotaxis, volume of fluid influx, and fluid concentrations of lysosomal and lactic dehydrogenase (LDH) enzymes. In addition, the enzyme content of inflammatory fluid neutrophils may also be determined. A parallel time course of neutrophil and lysosomal enzyme influx into sponge implants was observed. This was characterized by an initial lag phase and a rapid increase between 5 and 16 h. The origin of supernatant LDH and lysosomal enzymes was studied with anti-neutrophil serum to produce agranulocytic rats. Inflammatory fluid in these rats was almost acellular and contained decreased concentrations of beta glucuronidase (-96%) and LDH (-74%). In control rats all of the supernatant beta glucuronidase could be accounted for by cell death and lysis, as estimated from measurements of soluble DNA. Only 15-20% of the LDH activity could be accounted for on the basis of cell lysis. The remainder was derived from neutrophil-mediated injury to connective tissue cells. Large intravascular doses of methylprednisolone markedly inhibited neutrophil influx into sponges and adjacent connective tissue. Secondary to decreased neutrophil influx, fewer neutrophils were available for lysis, and lysosomal enzyme levels in inflammatory fluid decreased. No evidence for intracellular or extracellular stabilization of neutrophil lysosomal granules by methylprenisolone was found.