Intrathecal bupivacaine and morphine toxicity leading to transient hypotension and delayed status epilepticus.

BACKGROUND: Local anesthetic systemic toxicity characteristically occurs after inadvertent intravascular injection of local anesthetics; however, it is unclear if similar symptoms arise after intrathecal adminstration. Intrathecal use of local anesthetics for chronic pain is increasing and carries a potential risk of toxicity. Experience with the presenting symptoms and appropriate treatment for intrathecal local anesthetic toxicity is limited. CASE STUDY: A 74-year-old woman with an intrathecal bupivacaine/morphine pump developed lower extremity sensory neuropathy followed by obtundation, hypotension, and lower extremity flaccidity after an intrathecal pump refill. Her condition evolved to status epilepticus (SE) refractory to standard treatment. Intravenous fat emulsion (IFE) was administered, but was not immediately effective thus necessitating phenobarbital loading and propofol infusion. Despite significant bupivacaine neurotoxicity, no cardiotoxicity developed. DISCUSSION: The patient developed intrathecal local anesthetic and opioid toxicity after a malfunction of her intrathecal pump during a refill. We hypothesize that no cardiotoxicity developed secondary to sequestration of bupivacaine within the central nervous system. Likewise, poor CNS penetration of intravenous lipid emulsion may have negated or delayed any antidotal effect. CONCLUSION: We present a case of intrathecal toxicity leading to prolonged spinal anesthesia, progressive encephalopathy, and SE refractory to intravenous lipid emulsion. Management of SE with benzodiazepines and barbiturates may be more effective than lipids in cases of toxicity from intrathecal administration of bupivacaine.

High dose insulin for beta-blocker and calcium channel-blocker poisoning.

BACKGROUND/OBJECTIVES: High dose insulin (HDI) is a standard therapy for beta-blocker (BB) and calcium channel-blocker (CCB) poisoning, however human case experience is rare. Our poison center routinely recommends HDI for shock from BBs or CCBs started at 1U/kg/h and titrated to 10U/kg/h. The study objective was to describe clinical characteristics and adverse events associated with HDI. METHODS: This was a structured chart review of patients receiving HDI for BB or CCB poisoning with HDI defined as insulin infusion of ≥0.5U/kg/h. RESULTS: In total 199 patients met final inclusion criteria. Median age was 48years (range 14-89); 50% were male. Eighty-eight patients (44%) were poisoned by BBs, 66 (33%) by CCBs, and 45 (23%) by both. Median nadir pulse was 54 beats/min (range 12-121); median nadir systolic blood pressure was 70mmHg (range, 30-167). Forty-one patients (21%) experienced cardiac arrest; 31 (16%) died. Median insulin bolus was 1U/kg (range, 0.5-10). Median starting insulin infusion was 1U/kg/h (range 0.22-10); median peak infusion was 8U/kg/h (range 0.5-18). Hypokalemia occurred in 29% of patients. Hypoglycemia occurred in 31% of patients; 50% (29/50) experienced hypoglycemia when dextrose infusion concentration ≤10%, and 30% (31/105) experienced hypoglycemia when dextrose infusion concentration ≥20%. CONCLUSIONS: HDI, initiated by emergency physicians in consultation with a poison center, was feasible and safe in this large series. Metabolic abnormalities were common, highlighting the need for close monitoring. Hypoglycemia was more common when less concentrated dextrose maintenance infusions were utilized.

Use of Intravenous Fat Emulsion in the Emergency Department for the Critically Ill Poisoned Patient.

BACKGROUND: Multiple case reports of using intravenous fat emulsion (IFE) as an antidote for human poisoning from various xenobiotics have been published over the last decade. Given the rapidly evolving field, emergency physicians may be uncertain about the indications, timing, and dose for IFE treatment. METHODS: A PubMed literature search was conducted from January 1996 to November 2015 and limited to human studies written in English and articles with relevant keywords. Guideline statements and nonsystematic reviews were excluded. Studies identified then underwent a structured review of their results. RESULTS: There were 986 papers fulfilling the search criteria screened, and 85 appropriate articles were rigorously reviewed in detail. Recommendations were given on indications, timing, and dose of IFE. Most of these were based on case reports and anecdotal experience. DISCUSSION: In critically ill patients with refractory shock or cardiac arrest after a suspected overdose of local anesthetics or selected xenobiotics, IFE may be considered as a potentially beneficial adjunctive treatment. Despite an abundance of reports on the use of IFE on xenobiotics poisoning, the quality of evidence is suboptimal and fraught with reporting bias. CONCLUSIONS: IFE may be an effective antidote in poisonings from various xenobiotics. However, further research is needed to determine its optimal circumstances, timing, and dose of use.

Glyphosate surfactant herbicide poisoning and management.

Glyphosate is a widely used herbicide in agriculture, forestry, industrial weed control and aquatic environments. Glyphosate potential as herbicide was first reported in 1971. It is a non-selective herbicide. It can cause a wide range of clinical manifestations in human beings like skin and throat irritation to hypotension, oliguria and death. We are reporting a case of a 35-year-old male patient who was admitted to our tertiary care hospital following intentional ingestion of around 200 ml of herbicide containing glyphosate. Initially, gastric lavage done and the patient was managed with intubation and mechanical ventilation, noradrenaline and vasopressin infusion, continuous veno-venous hemodiafiltration and intravenous (IV) lipid emulsion (20% intralipid 100 ml), patient was successfully treated and discharged home. This case report emphasizes on timely systemic supportive measure as a sole method of treatment since this poison has no known specific antidote and the use of IV lipid emulsion for a successful outcome.

Hyperuricemia and intravenous fat emulsion are risk factors for gout flares during active gastrointestinal bleeding: a case control study.

OBJECTIVE: It is well-established that patients with a history of gout are more susceptible to experiencing gastrointestinal bleeding. Gout flare during active gastrointestinal bleeding poses a significant challenge due to the gastrointestinal side effects of anti-inflammatory therapy. This study sought to investigate the risk factors associated with gout flares during episodes of gastrointestinal bleeding. METHODS: We conducted a retrospective observational study involving 94 patients who experienced active gastrointestinal bleeding and had a history of gout. This study was conducted at Jinhua Municipal Central Hospital from January 2019 to October 2022. We collected and recorded demographic information and clinical characteristics. RESULTS: Among the gout flare patients, hyperuricemia and intravenous fat emulsion therapy were more prevalent compared to those who remained stable (81.6% vs. 57.8% and 46.9% vs. 24.4%, p < 0.05). Multivariate logistic regression analysis revealed that both hyperuricemia (odds ratio 2.741, 95% CI 1.014-7.413, p = 0.047) and intravenous fat emulsion therapy (odds ratio 2.645, 95% CI 1.046-6.686, p = 0.040) were independent predictors of gout flares. Furthermore, gout attacks occurred sooner in patients receiving intravenous fat emulsion therapy compared to those not receiving it (median: 4 days (interquartile range: 2) vs. median: 5 days (interquartile range: 2.25), p = 0.049). CONCLUSION: Our study revealed a high incidence of gout flares during episodes of active gastrointestinal bleeding, with patients undergoing intravenous fat emulsion therapy and those with hyperuricemia being at increased risk.

Comparative effectiveness of two lipid emulsions in preventing retinopathy of prematurity in preterm infants requiring parenteral nutrition.

OBJECTIVES: The main aim was to compare the effects of 2 parenteral lipid emulsions on retinopathy of prematurity (ROP) incidence, severity, and need for treatment. Secondary aim was to compare the effect on weight gain in the first 6 weeks of life. METHODS: Single-center, observational, retrospective study analyzing preterm infants with a gestational age (GA) <31 weeks and a birth weight <1251 g born between April 2015 and December 2018. The infants' medical records were reviewed to collect clinical data. Parenteral nutrition (PN) details were obtained from the hospital pharmacy database. RESULTS: In total, 180 patients were included: 90 received ClinOleic® and 90 received SMOFlipid®. No significant differences were observed for the incidence of ROP (40% in ClinOleic® group and 41% in SMOFlipid® group, p=.88) or ROP requiring treatment (4% and 10%, respectively, p=.152). Weekly weight gain was similar in the 2 groups. CONCLUSIONS: This study showed no difference between the 2 groups regarding ROP, ROP requiring treatment, or weekly weight gain in the first 6 weeks of life.

Comparative effectiveness of two lipid emulsions in preventing retinopathy of prematurity in preterm infants requiring parenteral nutrition. / [Artículo traducido] Efectividad comparativa de 2 emulsiones lipídicas en la prevención de la retinopatía del prematuro en neonatos pretérmino que requieren nutrición parenteral.

OBJECTIVES: The main aim was to compare the effects of two parenteral lipid emulsions on retinopathy of prematurity (ROP) incidence, severity, and need for treatment. Secondary aim was to compare the effect on weight gain in the first 6 weeks of life. METHODS: Single-center, observational, retrospective study analyzing preterm infants with a gestational age < 31 weeks and a birth weight < 1,251 g, born between April 2015 and December 2018. The infants' medical records were reviewed to collect clinical data. Parenteral nutrition details were obtained from the hospital pharmacy database. RESULTS: In total, 180 patients were included: 90 received ClinOleic® and 90 received SMOFlipid®. No significant differences were observed for the incidence of ROP (40% in ClinOleic® group and 41% in SMOFlipid® group, p=0.88) or ROP requiring treatment (4% and 10% respectively, p=0.152). Weekly weight gain was similar in the two groups. CONCLUSIONS: This study showed no difference between the two groups regarding ROP, ROP requiring treatment or weekly weight gain in the first 6 weeks of life.

A Case Report of Flecainide Toxicity With Review of Literature.

Flecainide is an anti-arrhythmic drug with a narrow therapeutic index. Flecainide toxicity is rare, but the mortality is high. This case demonstrates the use of intravenous fat emulsion therapy in conjunction with intravenous sodium bicarbonate treatment for flecainide toxicity. A 50-year-old male with atrial fibrillation and taking flecainide 75 mg twice daily presented to Emergency Department after ingesting 1125 mg of flecainide, in a suicide attempt. An electrocardiogram (ECG) on arrival showed bradycardia, wide QRS complex, prolonged QTc interval. Treatment for flecainide poisoning with intravenous sodium bicarbonate was initiated. On day two, the patient had a cardiac arrest secondary to ventricular tachycardia. After successful defibrillation, the patient had persistent bradycardia and hypotension. Administration of a 20% lipid emulsion bolus, followed by continuous infusion for three hours, resulted in conversion to normal sinus rhythm. This case illustrates the successful treatment of flecainide toxicity with intravenous fat emulsion therapy. To our knowledge, this is the second case that used fat emulsion without concomitant extracorporeal life support. Due to its low prevalence and the fact the lipid emulsion is often used in conjunction with other treatments, there are no randomized clinical trials on the isolated efficacy of lipid infusion. The best treatment is unknown. Given its high mortality, early detection and treatment are paramount.

Lipid-Free PN is Associated with an Increased Risk of Hyperbilirubinemia in Surgical Critically Ill Patients with Admission Hepatic Disorder: A Retrospective Observational Study.

BACKGROUND: To evaluate the effect of different PN types on surgical critically ill trauma/acute care surgery patients with hepatic disorders at admission. METHODS: This is a retrospective study. The PN types included lipid-free, soybean oil/medium-chain triglyceride, olive oil-based, and fish oil-containing PNs. Patients admitted with liver injury or liver surgery, elevated serum AST/ALT level, and elevated serum total bilirubin level were included. The exclusion criteria are as follows: 1) age <18 years, 2) severe liver disease/cirrhosis, 3) received more than one type of PN and 4) serum total bilirubin >4.9 mg/dl at admission. Demographics, severity, comorbidities, blood stream infection, hyperbilirubinemia (total bilirubin > 6.0 mg/dl), and mortality were collected for analysis. We also performed analysis stratified by separated lipid doses (g/kg/day). RESULTS: A total of 156 patients were enrolled. There were no demographic differences among groups. The lipid-free group was associated with the highest mortality rate and incidence of hyperbilirubinemia. Compared to the lipid-free group, the olive oil-based group had the lowest risk of hyperbilirubinemia. After being stratified by separated lipid doses, the incidence of hyperbilirubinemia decreased when the lipid dosage increased. Regarding different types of lipids, patients who received more than the median dosage of lipids showed a significantly lower risk of hyperbilirubinemia, except in the fish oil-containing group. CONCLUSION: Our result suggested that lipid-free PN is associated with an increased risk of hyperbilirubinemia in surgical critically ill patients with admission hepatic disorder. Further studies are warranted.

Resolution of Severe Neurologic Signs Following Intravenous Lipid Emulsion Therapy in a Young Dog With a Portosystemic Shunt: Case Report.

A 5-month-old male intact Great Pyrenees was presented for an acute onset of severe neurologic signs (stupor, absent menace, intermittent head turn to the left). The patient's history included possible naproxen ingestion with a maximum ingested dose of 59 mg/kg, exceeding the reported dose of >50 mg/kg known to cause neurologic signs. Blood sampling for baseline bloodwork was performed, and intravenous lipid emulsion (ILE) was subsequently administered, for treatment of the suspected toxicosis. Due to severe and life-threatening neurologic signs, other methods of decontamination were contraindicated and unlikely to be effective; extracorporeal therapy was also unavailable. Complete resolution of neurologic signs occurred 30 min after completion of ILE therapy. At this time, the owners found the missing naproxen tablets after returning home and the bloodwork results returned revealing findings consistent with hepatic encephalopathy. The fasted blood ammonia concentration immediately prior to ILE administration was 702.1 µg/dL (reference interval, RI: 24-36 µg/dL) and decreased to 194.1 µg/dL 24 h later. In the first 24 h, the patient also received three doses of lactulose, N-acetylcysteine, and intravenous fluids. The patient was subsequently diagnosed with a single, large intrahepatic portosystemic shunt via computed tomography and underwent an endovascular coil embolization procedure. Given the rapid and dramatic improvement in severe neurologic signs after ILE therapy alone, it is strongly suspected that this treatment resulted in improvement of hepatic encephalopathy.

Recommendations for photoprotection of parenteral nutrition for premature infants: An ASPEN position paper.

Although crucial in improving health outcomes in the preterm infants, parenteral nutrition (PN) is not without risk, especially if handled improperly. A growing body of evidence suggests that components of PN admixtures, including lipid injectable emulsions (ILEs), are susceptible to degradation, including oxidation when exposed to light (ie, photo-oxidation), resulting in the production of reactive oxygen species. Infants, especially those born preterm, are considered more susceptible to consequences of oxidative stress than children and adults. Oxidative stress is associated with bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and intestinal failure-associated liver disease. The American Society for Parenteral and Enteral Nutrition (ASPEN) assembled a working group to provide recommendations on clinical practice surrounding photoprotection of PN.This Position Paper reviews the scientific literature on the formation of quantifiable peroxides and other degradation products when PN admixtures and ILEs are exposed to light and reports adverse clinical outcomes in premature infants exposed to PN. Recommendations for photoprotection of PN admixtures and ILEs are provided, as well as the challenges in achieving complete photoprotection with the equipment, supplies, and materials currently available in the US. ASPEN and the authors understand that the full implementation of complete photoprotection may not currently be feasible given current product availability; recommendations provided in this paper serve to represent the goal to which to strive as well as to highlight the importance of product availability to achieve these practices. This paper has been approved by the ASPEN Board of Directors.

Lipid-Free Parenteral Nutrition Is Associated with an Increased Risk of Hepatic Dysfunction in Surgical Critically Ill Patients: A Retrospective Observational Study.

To evaluate the effects of lipid-free parenteral nutrition (PN) and various intravenous fat emulsions (IVFEs) on hepatic function in surgical critically ill trauma/acute care surgery patients. We retrospectively reviewed trauma/acute care surgery patients without admission hepatic disorder that received PN. The PN groups include lipid-free, soybean oil/medium-chain triglyceride, olive oil-based, and fish-oil contained PN. We excluded patients with (1) age <18 years, (2) without surgery, (3) preexisting liver injury/diseases, (4) hyperbilirubinemia at admission, (5) received more than one type of PN, and (6) repeated ICU episodes in the same hospitalization. Hepatic dysfunction was considered as serum total-bilirubin >6.0 mg/dL. The demographics, severity score, comorbidities, blood stream infection, and mortality were collected for analyses. The major outcome is hepatic function. We also performed analyses stratified by separated lipid doses (g/kg/day). A total of 249 patients were enrolled. There were no demographic differences among groups. The lipid-free PN group had a higher incidence of hepatic dysfunction and mortality. Compared to the lipid-free group, the other three IVFEs had significantly lower risks of hepatic dysfunction, while the olive oil-based group had a significantly lower risk of 30 and 90-day mortality. After being stratified by separating lipid doses, the soybean oils showed a decreasing trend of hepatic dysfunction and mortality with increased dosage. Fish oil >0.05 g/kg/day was associated with lower hepatic dysfunction incidences. Our findings suggest that, when compared to IVFEs, surgical critically ill patients with trauma/acute care surgery that received lipid-free PN are associated with an increased risk of hepatic dysfunction. In addition, the olive oil-based group had a significantly lower risk of mortality, while fish oil >0.05 g/kg/day was associated with lower incidences of hepatic dysfunction; however, further studies are warranted.

Effective management of acute postoperative pain using intravenous emulsions of novel ketorolac prodrugs: in vitro and in vivo evaluations.

The aim was to prepare intravenous fat emulsions (IFEs) of ketorolac (KTL) ester prodrugs and to investigate the pharmacokinetics and pharmacodynamics of these formulations. Three prodrugs of KTL (KTL-IS, KTL-AX and KTL-BT) were synthesized as a means to increase the lipid solubility of KTL. All KTL prodrugs with higher Log P values presented increased tendency to partition into a blank IFE using extemporaneous addition method - the encapsulation efficiency of KTL-IS IFE and KTL-BT IFE was more than 97%. The particle sizes and zeta potentials of these two formulations were comparable to that of the blank IFE. PK studies in rabbits showed significant larger AUC0-8h (646.969 ± 154.326 mg/L•h-1 for KTL-IS IFE and 559.426 ± 103.057 mg/L•h-1 for KTL-BT IFE) than that of ketorolac tromethamine (KTL-T) injectable (286.968 ± 63.045 mg/L•h-1) and approximately 2-fold increases in the elimination t1/2 over KTL-T. In a rat postoperative pain model, the paw withdrawal thresholds and the paw withdrawal latency after I.V. KTL prodrug IFEs were significantly higher than that after I.V. KTL-T at 3~4 h. Effective controlling of acute postoperative pain in a longer duration can be achieved by using non-addictive ketorolac derivatives intraveneous emulsions.

Essential Fatty Acid Requirements and Intravenous Lipid Emulsions.

Linoleic acid (LA) and α-linolenic acid (ALA) must be supplied to the human body and are therefore considered essential fatty acids. This narrative review discusses the signs, symptoms, diagnosis, prevention, and treatment of essential fatty acid deficiency (EFAD). EFAD may occur in patients with conditions that severely limit the intake, digestion, absorption, and/or metabolism of fat. EFAD may be prevented in patients requiring parenteral nutrition by inclusion of an intravenous lipid emulsion (ILE) as a source of LA and ALA. Early ILEs consisted solely of soybean oil (SO), a good source of LA and ALA, but being rich in LA may promote the production of proinflammatory fatty acids. Subsequent ILE formulations replaced part of the SO with other fat sources to decrease the amount of proinflammatory fatty acids. Although rare, EFAD is diagnosed by an elevated triene:tetraene (T:T) ratio, which reflects increased metabolism of oleic acid to Mead acid in the absence of adequate LA and ALA. Assays for measuring fatty acids have improved over the years, and therefore it is necessary to take into account the particular assay used and its reference range when determining if the T:T ratio indicates EFAD. In patients with a high degree of suspicion for EFAD, obtaining a fatty acid profile may provide additional useful information for making a diagnosis of EFAD. In patients receiving an ILE, the T:T ratio and fatty acid profile should be interpreted in light of the fatty acid composition of the ILE to ensure accurate diagnosis of EFAD.

Intravenous Lipid Emulsions in Veterinary Clinical Toxicology.

Use of intravenous lipid emulsion (ILE) as an antidote for severe cardiotoxicity and neurotoxicity has expanded in the veterinary world in the past decade. Despite advances in understanding of potential mechanisms of action of antidotal ILE, knowledge gaps remain in efficacy, appropriate dosing rates for various toxicants, and potential adverse reactions. Use of ILE in management of toxicoses of veterinary patients should be considered investigational, and should not be first-line treatment of most toxicoses, especially where established treatment protocols have good likelihood of positive outcomes. Use of ILE in veterinary toxicology cases requires judicious assessment of individual cases and proper informed consent of clients.

Intravenous Fat Emulsion for Treatment of Local Anesthetic Systemic Toxicity: Best Practice and Review of the Literature.

Local anesthetic systemic toxicity (LAST), although rare, can be a fatal complication after regional anesthesia. The use of intravenous (IV) fat emulsion as a treatment of LAST is controversial among clinicians worldwide. This literature review aims to identify existing data supporting the use of IV lipids in the management of LAST and current best evidence-based practice by anesthesia providers during a LAST event. More than 120 articles resulted from a systematic literature search that was conducted using major search engines. Of those articles, 25 were included in this literature review. The safe use of IV lipids for the treatment of LAST is supported in the literature. Yet, there is still lack of awareness on lipid rescue therapy despite the significant evidence of its positive outcome. In the setting of local-anesthetic toxicity, lipid rescue should be considered first-line treatment. Intravenous lipids must be readily available in all institutions performing regional anesthesia. Education on their use, storage, and dosage is vital among anesthesia departments in the United States and worldwide.

Controversies in the Use of Lipid Injectable Emulsion in Hospitalized Patients.

Soybean oil-based lipid injectable emulsion (SO-based ILE) is an 18-carbon, ω-6 macronutrient providing a concentrated source of calories, which can be administered in or with parenteral nutrition to patients unable to tolerate or consume adequate enteral nutrition. Beyond the provision of energy, SO-based ILE provides linoleic and linolenic acid, 2 essential fatty acids necessary for the prevention of essential fatty acid deficiency. However, SO-based ILE with its high levels of ω-6 fatty acids, long-chain triglycerides, phospholipid emulsifiers, and glycerin has been associated with worsening clinical outcomes, including increase of infections, lengthier intensive care and hospital stay, and prolonged mechanical ventilation. Recognizing this, studies have investigated omitting SO-based ILE in the critically ill patient for the first 7 days to observe if clinical outcomes are improved. Unfortunately, there is extremely limited research, and what is available is controversial. National guidelines have analyzed the studies, and they too are challenged to define a clear, high quality of evidence recommendation. It is important for the healthcare clinician to understand the research around this controversy to make best decisions for their patients.

New Strategy to Reduce Hypertriglyceridemia During Parenteral Nutrition While Maintaining Energy Intake.

BACKGROUND: Hypertriglyceridemia is a frequent metabolic complication associated with fat administration in parenteral nutrition (PN). No clear guidelines have been published on how to proceed once hypertriglyceridemia has been detected. A new strategy could be to substitute the initial fat emulsion with another emulsion with faster clearance. Our objective was to determine the effectiveness in reducing triglyceridemia values, maintaining the caloric intake, and improving nutrition parameters in patients who had moderate hypertriglyceridemia during PN when an olive oil-based fat emulsion (OOFE) was substituted with a multiple-source oil fat emulsion (MOFE). We also assessed the safety of this substitution in hepatic and glycemic profiles. MATERIALS AND METHODS: We performed a retrospective, observational study that included 38 adult patients to whom OOFE in PN was substituted with MOFE when moderate hypertriglyceridemia (≥250-400 mg/dL) was detected. RESULTS: Triglyceridemia values decreased in 36 (94.7%) patients. The mean reduction was 71 (88-22) mg/dL. Fat load was slightly reduced after substitution (-0.14 [-0.23 to 0] g/kg/d; P < .001), but total caloric intake increased from 22.5 (19.7-25.1) to 23.1 (19.8-26.8) kcal/kg/d (P = .053). After substitution, nutrition parameters improved, liver parameters remained unchanged, and insulin requirements increased. CONCLUSION: The substitution of OOFE with MOFE in patients with moderate hypertriglyceridemia during PN resulted in a reduction in triglyceridemia values of about 70 mg/dL. That allowed maintaining the caloric intake and improved nutrition parameters without affecting the hepatic profile. For some patients, insulin requirements increased moderately.

Bone metabolism in very preterm infants receiving total parenteral nutrition: do intravenous fat emulsions have an impact?

Very preterm infants (<32 weeks' gestation) are at high risk for impaired skeletal development because of factors that limit the provision of extrauterine nutrients. Cumulative net deficiencies of calcium, phosphorus, docosahexaenoic acid (DHA), and arachidonic acid (ARA) are evident in these infants after prolonged administration of total parenteral nutrition (TPN). This is significant because minerals as well as metabolites of DHA and ARA are important modulators of bone cell differentiation, lengthening of bone, and bone matrix deposition. Furthermore, diets containing only precursors of DHA and ARA result in suboptimal skeletal growth. With the emergence of new intravenous lipid emulsions, it is important to understand the impact of fatty acids on bone metabolism in the third trimester in order to optimize the provision of TPN in very preterm infants. The purpose of this review is to evaluate current evidence regarding intravenous lipid emulsions and bone metabolism in very preterm infants receiving prolonged TPN and to identify areas of research needed.

Solubility of volatile anesthetics in plasma substitutes, albumin, intravenous fat emulsions, perfluorochemical emulsion, and aqueous solutions.

Using the gas chromatographic headspace sampling technique, we determined the solubility of volatile anesthetics (halothane, enflurane, isoflurane, and sevoflurane) in plasma substitutes, albumin solution, intravenous fat emulsions, perfluorochemical FC-43 emulsion, and aqueous solutions at 37°C. The order of magnitude of λ value (liquid/gas partition coefficients) was halothane >enflurane>isoflurane> sevoflurane in all the parenteral infusion fluids except the perfluorochemical emulsion (FC-43). The FC-43/gas partition coefficients of the volatile anesthetics were almost the same at 5.5. The partition coefficients were affected by the osmolarity of solutions, hydrophobicity, and the structure of solutes. Also, the blood/gas partition coefficients in intravenous fat emulsions and FC-43 were calculated. It is suggested that fluid therapy, especially with intravenous fat emulsions or FC-43, may influence the blood/gas partition coefficients of anesthetics, and affect the induction of anesthesia.