Effects of short-term propofol administration on pancreatic enzymes and triglyceride levels in children

Triglyceride Concentrations and Their Relationship to Sedation Choice and Outcomes in Mechanically Ventilated Patients Receiving Propofol

Rationale: Propofol is a first-line sedative agent in the intensive care unit (ICU) but may be associated with hypertriglyceridemia and pancreatitis. To date, the relationship between propofol-induced hypertriglyceridemia and pancreatitis, as well as clinician responses to propofol-induced hypertriglyceridemia, have not been comprehensively studied. Objectives: To assess the incidence of hypertriglyceridemia and pancreatitis in patients receiving continuous propofol infusions in the ICU and to describe the association between hypertriglyceridemia and the use of nonpropofol continuous sedative infusions. Methods: This was a retrospective observational cohort study conducted at three urban academic hospitals within a single health system. Findings were additionally validated using the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database containing data from a separate tertiary care hospital. Mechanically ventilated adult patients who received a continuous propofol infusion between 2016 and 2021 were included. The primary exposure was serum triglyceride concentration, and hypertriglyceridemia was defined as a triglyceride concentration greater than 400 mg/dl. Outcomes included new-onset pancreatitis as well as receipt of midazolam, dexmedetomidine, or ketamine after the triglyceride measurement. The incidence of pancreatitis was compared between groups using a Fisher's Exact test. Multivariable logistic regression was used to assess the association between dichotomized triglyceride concentration and alternative sedative use. Results: In the primary cohort of 7,037 patients, 1,724 (24.5%) had one or more triglyceride concentration measured. Of these, 1,365 (79.2%) had a maximum concentration of less than 400 mg/dl, and 359 (20.8%) had a maximum concentration of greater than 400 mg/dl. Compared with patients with low triglyceride concentrations, patients with high triglyceride concentrations were more likely to receive a continuous infusion of midazolam (37.0% vs. 16.4%; adjusted odds ratio [aOR], 3.1; 95% confidence interval [CI], 2.2-4.4; P < 0.01), ketamine (22.8% vs. 6.9%; aOR, 3.5; 95% CI, 2.3-5.3; P < 0.01), and dexmedetomidine (57.7% vs. 46.6%; aOR, 1.5; 95% CI, 1.1-2.0; P < 0.01). Rates of midazolam infusion increased as triglyceride concentrations exceeded 500 mg/dl. Forty-four (0.6%) patients developed pancreatitis after propofol initiation, of which 4 (9.1%) were considered related to propofol-associated hypertriglyceridemia. Findings were similar in the MIMIC-IV cohort. Conclusions: Propofol-associated hypertriglyceridemia is relatively common in mechanically ventilated ICU patients who have triglycerides measured. Pancreatitis related to propofol-associated hypertriglyceridemia is rare. Patients who develop hypertriglyceridemia while receiving propofol are more likely to receive continuous infusions of other sedatives.

Severe necrotizing pancreatitis immediately after non-abdominal surgery under general anesthesia with propofol

Postoperative pancreatitis is a relatively rare disease and is poorly recognized. Herein, we present a case of necrotizing pancreatitis that developed immediately after non-abdominal surgery under general anesthesia. In this report, 4 h after thyroidectomy under general anesthesia using propofol, the patient developed upper abdominal pain and was diagnosed with severe acute pancreatitis with extensive pancreatic necrosis. Immediately after the diagnosis, the patient received appropriate treatment, and acute pancreatitis was improved. Subsequently, the patient has the formation of non-infectious giant walled-off necrosis and remained in good condition without additional treatment for 1.5 years after pancreatitis onset. In this case report, our detailed causative search suggested that propofol administration could be the cause of this pancreatitis. Propofol-induced pancreatitis is extremely rare but develops often severely, resulting in fatality. In this case, the patient developed severe acute pancreatitis within a very short time after surgery but was able to survive by immediate intervention of treatment. We suggest that clinicians should consider acute pancreatitis as a life-threatening adverse event under general anesthesia with propofol and perform thorough postoperative management.

Propofol-Induced Severe Necrotizing Pancreatitis

Propofol is a widely used sedative for gastrointestinal endoscopic procedures. Drug-induced pancreatitis is a relatively rare disease possibly because of poor recognition. Propofol-induced pancreatitis is an extremely rare phenomenon. We present a 22-year-old healthy man who underwent esophagogastroduodenoscopy with propofol as a sedative. Soon after, he developed acute upper gastrointestinal symptoms and was diagnosed with pancreatitis. His prolonged hospital course was complicated with necrotizing pancreatitis, acute respiratory distress syndrome, septic shock, and other end-organ damages. We hope to increase awareness of a life-threatening adverse event of a commonly used anesthetic such as propofol.

The Effects of Propofol Anesthesia on Lipid Profile and Some Biochemical Indices in Cats

The aim of the present study was to evaluate lipid profile (triglyceride, total cholesterol, HDL, LDL, and VLDL), pancreas (lipase and amylase), liver (AST, ALT, and ALP), blood urea nitrogen, creatinine, uric acid, sodium and potassium function indicators in cats undergoing two different durations of anesthesia with propofol. Ten adult female cats were randomly divided into two groups (n= 5) and anaesthetized with propofol 1% (induction: 8 mg/kg; infusion: 0.3 mg/kg/min) for either 45 or 90 minutes. Blood samples were collected at predetermined intervals up to 72 hours later. Comparison of the measured variables between treatments did not show significant differences. Triglyceride and cholesterol levels showed significant increase after induction of anesthesia (P < .05). The highest triglyceride and cholesterol values were recorded at 6 and 24 hours. HDL was lower while LDL and VLDL were higher at several time points after anesthesia (P < .05). Higher values of lipase, ALT and AST were detected after induction (P < .05). All the observed alterations were within normal ranges. In conclusion, propofol anesthesia was associated with some changes in lipid profile, as well as pancreatic and liver function indices, which should be considered in clinical situations. It seems that in the absence of pre- or co-existing disturbances, induction and maintenance of anesthesia with propofol did not carry additional risk to cats.

In vivo study of hepatic oxidative stress and mitochondrial function in rabbits with severe hypotension after propofol prolonged infusion

In humans, prolonged sedations with propofol or using high doses have been associated with propofol infusion syndrome. The main objective of this study was to evaluate the effects of prolonged high-dose administration of a specific propofol emulsion (Propofol Lipuro) and an improved lipid formulation (SMOFlipid) in liver mitochondrial bioenergetics and oxidative stress of rabbits, comparatively to a saline control. Twenty-one male New Zealand white rabbits were randomly allocated in three groups that were continuously treated for 20 h. Each group of seven animals received separately: NaCl 0.9 % (saline), SMOFlipid (lipid-based emulsion without propofol) and Lipuro 2 % (propofol lipid emulsion). An intravenous propofol bolus of 20 mg kg⁻¹ was given to the propofol Lipuro group to allow blind orotracheal intubation and mechanical ventilation. Anesthesia was maintained using infusion rates of: 20, 30, 40, 50 and 60 mg kg⁻¹ h⁻¹, according to the clinical scale of anesthetic depth and the index of consciousness values. The SMOFlipid and saline groups received the same infusion rate as the propofol Lipuro group, which were infused during 20 consecutive hours. At the end, the animals were euthanized, livers collected and mitochondria isolated by standard differential centrifugation. Mitochondrial respiration, membrane potential, swelling and oxidative stress were evaluated. Data were processed using one-way ANOVA (p < 0.05). The animals revealed a significant decrease in cardiovascular parameters showing bradycardia and severe hypotension. No statistical differences were observed when using pyruvate as substrate, however, when using succinate as respiratory substrate, significant decrease in ADP-stimulated respiration rate was observed for SMOFlipid group (p = 0.002). Lipid peroxides (p < 0.01) and protein carbonyls (p = 0.01) showed a statistically significant difference between propofol Lipuro and the SMOFlipid groups. These results suggest that lipid-based emulsions can be involved in the regulation of different pathways that ultimately lead to a decrease of state 3 mitochondrial respiration rate. The infusion of propofol Lipuro during prolonged periods, in addition to marked hypotension and hypoperfusion, also showed to have higher anti-oxidant activity and lower impairment of the mitochondrial function comparatively to the improved lipid formulation, SMOFlipid, using the rabbit as animal model.

Comparison of serum triglyceride levels with propofol in long chain triglyceride and propofol in medium and long chain triglyceride after short term anesthesia in pediatric patients

BACKGROUND

Significant increase in serum triglyceride (ST) concentration have been described in adult population after prolonged administration of propofol formulation containing long chain triglyceride (LCT). Though, medium chain triglyceride-LCT (MCT-LCT) propofol when compared with LCT propofol for long-term sedation in adults resulted in identical triglyceride levels, the elimination of triglyceride was faster in patients administered MCT-LCT propofol.

MATERIALS AND METHODS

A total of 40 children were randomized into two groups of 20 each; Group I were induced with 1% LCT propofol (3 mg/kg) and Group II with 1% medium and LCT propofol and maintained with descalating dose of 20.15 and 10 mg/kg/h at 10 min intervals. Blood samples for ST concentration were obtained before induction of anesthesia, at the end of propofol infusion and 4 h after terminating propofol infusion.

RESULTS

ST levels were raised significantly above the basal values in both the groups but the rise was significantly higher in Group I (P < 0.05). Four hours after stopping propofol infusion the triglyceride levels were similar to the basal values in Group II, whereas in Group I the values were significantly greater than the baseline (P < 0.05) as well as those of Group II (P < 0.05). No clinically significant adverse effect of hypertriglyceridemia was observed.

CONCLUSION

Even short term anesthesia with LCT and MCT-LCT propofol (1%) leads to elevated ST levels. The increase in ST levels is less with MCT-LCT propofol and elimination of triglyceride is also rapid after terminating MCT-LCT propofol infusion.

Effect of short-term propofol administration on pancreatic enzymes and lipid biochemistry in children between 1 month and 36 months

BACKGROUND

Use of propofol in pediatric age group has been marred by reports of its adverse effects like hypertriglyceridemia and acute pancreatitis, although a causal relation has not yet been established.

OBJECTIVES

This prospective, clinical trial was carried out to evaluate the effects of short-term propofol administration on serum lipid profile and serum pancreatic enzymes in children of ASA physical status I and II aged between 1 month and 36 months.

METHODS

Anesthesia was induced with Propofol (1%) in the dose of 3 mg·kg(-1) intravenously and was maintained by propofol infusion (0.5%) at the rate of 12 mg·kg(-1·) h(-1) for the first 20 min and at 8 mg·kg(-1·) h(-1) thereafter. The mean dose of propofol administered was 12.02 ± 2.75 mg·kg(-1) (fat load of 120.2 ± 27.5 mg·kg(-1) ). Lipid profile, serum amylase, and lipase were measured before induction of anesthesia, at 90 min, 4 h, and finally 24 h after induction.

RESULTS

Serum lipase levels (P < 0.05), serum triglyceride levels (P < 0.05), and serum very low-density lipoproteins VLDL levels (P < 0.05) were raised significantly after propofol administration from baseline although remained within normal limits. Serum cholesterol levels and serum low-density lipoproteins LDL levels showed a statistically significant fall over 24 h. No significant changes in serum pancreatic amylase levels were seen (P > 0.05). None of the patients developed any clinical features of pancreatitis in the postoperative period.

CONCLUSION

We conclude that despite a small, transient increase in serum triglycerides and pancreatic enzymes, short-term propofol administration in recommended dosages in children of ASA status I and II aged between 1 month and 36 months does not produce any clinically significant effect on serum lipids and pancreatic enzymes.

A death associated with possible propofol infusion syndrome

Propofol, an intravenously administered, centrally acting sedative/hypnotic, is a popular medication for anesthesia and sedation due to rapid onset, controllability and short recovery time. Prolonged propofol infusions, (>48 h) with elevated doses (>67 mcg/kg/min) may result in a rare but fatal condition known as the Propofol Related Infusion Syndrome (PRIS). This is a case of severe metabolic acidosis and refractory hyperkalemia in a 53 year old female with polytrauma on a continuous propofol infusion that was associated with fatal outcome.

Lipid-emulsion propofol less attenuates the regulation of body temperature than micro-emulsion propofol or sevoflurane in the elderly

PURPOSE

Anesthesia and surgery commonly cause hypothermia, and this caused by a combination of anesthetic-induced impairment of thermoregulatory control, a cold operation room environment and other factors that promote heat loss. All the general anesthetics markedly impair normal autonomic thermoregulatory control. The aim of this study is to evaluate the effect of two different types of propofol versus inhalation anesthetic on the body temperature.

MATERIALS AND METHODS

In this randomized controlled study, 36 patients scheduled for elective laparoscopic gastrectomy were allocated into three groups; group S (sevoflurane, n=12), group L (lipid-emulsion propofol, n=12) and group M (micro-emulsion propofol, n=12). Anesthesia was maintained with typical doses of the study drugs and all the groups received continuous remifentanil infusion. The body temperature was continuously monitored after the induction of general anesthesia until the end of surgery.

RESULTS

The body temperature was decreased in all the groups. The temperature gradient of each group (group S, group L and group M) at 180 minutes from induction of anesthesia was 2.5 ± 0.6°C, 1.6 ± 0.5°C and 2.3 ± 0.6°C, respectively. The body temperature of group L was significantly higher than that of group S and group M at 30 minutes and 75 minute after induction of anesthesia, respectively. There were no temperature differences between group S and group M.

CONCLUSION

The body temperature is maintained at a higher level in elderly patients anesthetized with lipid-emulsion propofol.

[Bupivacaine toxicity and propofol anesthesia : animal study on intravascular bupivacaine injection]

BACKGROUND

Several reports have confirmed the efficacy of Intralipid® (containing soya bean oil, egg phospholipids, glycerin and water) in the therapy of systemic local anesthetic intoxication. Pretreatment with Intralipid® shifted the dose-response to bupivacaine-induced asystole in rats. Whether intravenous anesthesia with propofol in the widely used medium chain triglyceride lipid emulsion increases the therapeutic range of systemically administered bupivacaine or not is unknown and was investigated in this study.

METHODS

A total of 30 piglets aged 2-6 weeks and weighing 4.5-6.5 kg were randomized into 2 groups and anesthetized with sevoflurane (group S) alone or with propofol 10 mg/kg body weight (BW)/h plus sevoflurane (group PS). After 60 min of steady state anesthesia arterial blood was sampled for assessment of blood gases, acid-base state and triglyceride plasma concentrations. Thereafter bupivacaine 0.125% was continuously infused by an infusion syringe pump through a central venous line at a rate of 4 mg/kg BW/min until invasively measured mean arterial pressure (MAP) was reduced by 50% of initial value. The bupivacaine infusion was stopped, blood for assessment of bupivacaine plasma concentration was drawn and the spontaneous hemodynamic course was observed. Resuscitation was not attempted. Results are presented as median and range. The Mann-Whitney U-test was used to assess differences between the two groups for triglyceride as well as for bupivacaine plasma concentrations measured at MAP 50%. A p-value≤0.05 was considered to be significant.

RESULTS

Baseline conditions (arterial blood pH, plasma protein and triglyceride plasma concentrations) did not differ significantly between the two groups. After 1 h of anesthesia, triglyceride plasma concentrations were significantly increased in group PS (median 0.69 mmol/l) compared to the corresponding baseline values (median 0.14 mmol/l; p<0.001) and to the 1 h values of group S (median 0.16 mmol/l; p<0.001). The total amount of bupivacaine administered was 9 mg/kg BW in both groups (6-13 mg/kg BW in group S, 5-13 mg/kg BW in group PS). Resulting bupivacaine plasma concentrations were 180 μmol/l (83-686 μmol/l) in group S and 185 μmol/l (130-465 μmol/l) in group PS. However, the total amount of bupivacaine administered and bupivacaine plasma concentrations at MAP 50% did not reveal statistically significant differences between the two groups but a huge variability of both parameters within each group was observed. None of the 30 piglets spontaneously recovered and they died from pulseless electrical activity or from asystolic cardiac arrest. The time from MAP 50% until cardiac arrest demonstrated a large variability but did not reveal significant differences between the two groups. The time to cardiac arrest was similar in both groups.

CONCLUSION

Medium/long chain triglyceride lipid emulsion (50:50) as widely used in propofol solutions did not increase therapeutic safety in cases of intravascular bupivacaine administration in this piglet model.

Propofol infusion syndrome

A review of the history, incidence, presentation, pathophysiology, and treatment of propofol infusion syndrome.

State of the art review: Intravenous fat emulsions: Current applications, safety profile, and clinical implications

OBJECTIVE

To review the current state of the science regarding intravenous fat emulsions (IVFEs), with an emphasis on their safety profile.

DATA SOURCES

Articles were identified via a search of the MEDLINE database, including publications from 1979 to December 2009, using a search string that included the terms parenteral nutrition, lipid emulsion, fat emulsion, IVFE, safety, adverse effect, neonate intralipid, and terms describing a range of specific adverse events (AEs) such as pancreatitis.

STUDY SELECTION AND DATA EXTRACTION

We selected articles that allowed us to compare the results of clinical trials involving delivery of medications via IVFEs with the historical use and effects of IVFEs in parenteral nutrition, with an emphasis on AEs. We focused on 2 drugs in current use that are administered intravenously in lipid emulsions: propofol and clevidipine.

DATA SYNTHESIS

Clearance of the fat particles in IVFEs is mediated by the enzyme lipoprotein lipase. AEs are more likely if the rate or duration of IVFE administration exceeds the enzyme's clearance capacity. AEs are also more likely after administration of a 10% IVFE formulation than a 20% formulation, because the higher concentration of free phospholipid in the 10% formulation interferes with lipoprotein lipase activity. AEs can be reduced by administering IVFEs at a dosage < or = 2.5 g/kg/day and at a rate < or = 0.11 g/kg/h. The anesthetic agent propofol, which is formulated in a 10% IVFE, has been used clinically for 25 years. Typical AEs associated with propofol use include infection, high plasma triglyceride concentrations, and pancreatitis. Recent clinical trials involving clevidipine, which is formulated in a 20% IVFE, have demonstrated a low rate of lipid-related AEs.

CONCLUSIONS

The results of this review demonstrate that IVFEs are well tolerated when administered in accordance with guideline recommendations.

Effects of medications on post-endoscopic retrograde cholangiopancreatography pancreatitis

BACKGROUND AND AIMS

Drug-induced pancreatitis accounts for about 2% of acute pancreatitis. The aim of this study is to determine whether propofol and other medications are associated with increased risk for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis.

METHODS

A retrospective study was conducted at a single tertiary care hospital. All patients who underwent ERCP from 2001 to 2004 were included. Diagnosis of acute post-ERCP pancreatitis was based on a consensus definition.

RESULTS

A total of 506 patients underwent ERCP. The total incidence of post-ERCP pancreatitis was 7.1%. There was no significant difference in post-ERCP pancreatitis between patients who received propofol compared to patients who received midazolam and fentanyl (9.0 vs. 5.9%, p = 0.18). Patients receiving an angiotensin receptor blocker were approximately 4 times more likely to develop post-ERCP pancreatitis (OR = 4.1, 95% CI 1.6-10.9). Patients younger than 65 years and smokers also had higher risk of developing acute post-ERCP pancreatitis than those who were older than 65 years (OR = 3.9, 95% CI 1.7-9.1) and non-smokers (OR = 2.8, 95% CI 1.3-6.2).

CONCLUSIONS

Propofol is a safe sedative drug for ERCP without additional risk of developing acute post-ERCP pancreatitis. Use of angiotensin receptor blockers, smoking and younger age are independent risk factors for post-ERCP pancreatitis.

Drug-induced acute pancreatitis in children receiving chemotherapy for acute leukemia: does propofol increase the risk?

BACKGROUND

The use of propofol is controversial in patients with a history of acute pancreatitis or those taking drugs, including certain chemotherapeutic drugs, that are associated with pancreatitis.

METHODS

To investigate this issue, we reviewed the medical records of all children who were diagnosed with pancreatitis while receiving chemotherapy for acute leukemia during a 5-year period.

RESULTS

A temporal relationship between propofol use and development of acute pancreatitis could not be established.

CONCLUSION

Propofol can be considered for general anesthesia in children who are receiving chemotherapeutic drugs that are themselves associated with acute pancreatitis or those who have a history of chemotherapy-induced pancreatitis.

Update on the propofol infusion syndrome in ICU management of patients with head injury

PURPOSE OF REVIEW

The propofol infusion syndrome is a rare condition characterized by the occurrence of lactic acidosis, rhabdomyolysis and cardiovascular collapse following high-dose propofol infusion over prolonged periods of time. Patients with traumatic brain injury are particularly at risk of developing this complication because large doses of propofol are commonly used to control intracranial pressure, whereas vasopressors are administered to augment cerebral perfusion pressure. In this review, we provide an update on the literature with particular emphasis on patients with traumatic brain injury.

RECENT FINDINGS

Several new case reports and reviews, as well as a number of experiments, have contributed significantly to our increased understanding of the cause of the syndrome. At the basis of the syndrome lies an imbalance between energy utilization and demand resulting in cell dysfunction, and ultimately necrosis of cardiac and peripheral muscle cells. Uncertainty remains whether a genetic susceptibility exists. Nonetheless, the growing number of case reports has made it possible to identify several risk factors.

SUMMARY

Propofol infusion syndrome is a rare but frequently lethal complication of propofol use. In patients with risk factors, such as traumatic brain injury, it is suggested that an infusion rate of 4 mg/kg per hour should not be exceeded. Early warning signs include unexplained lactic acidosis, lipemia and Brugada-like ECG changes. When these occur, propofol infusion should be discontinued immediately.

Propofol-induced hyperamylasaemia in a general intensive care unit

This study examined the incidence of hyperamylasaemia, in the absence of other plausible causes of pancreatic dysfunction, in intensive care unit (ICU) patients who received propofol. One-hundred-and-seventy-two consecutive patients of a general ICU who stayed for more than 24 hours were studied. Patients with a diagnosis consistent with elevated serum amylase levels at admission were excluded from the study, as were patients who had received medications known to raise serum amylase levels. Forty-four patients 53 +/- 20 years of age and median duration of ICU stay of five days (range two to 55) were eligible. Thirty of those, aged 54 +/- 21 years and median duration of ICU stay of five days (range two to 27) received continuous infusion of propofol for sedation (maximum dose 45 microg/kg/min). Of the 30 patients who received propofol, 16 (53%) developed hyperamylasaemia (125 to 466 IU/l) after two to nine days of continuous infusion. Liver and kidney function remained normal throughout the observation period. Of the 14 patients who did not receive propofol (aged 51 +/- 18 years), only two (14%) developed hyperamylasaemia, a significantly lower incidence (P = 0.021). Propofol infusion is associated with biochemical evidence of pancreatic injury. Amylase levels monitoring of propofol-sedated patients is warranted.

Propofol infusion syndrome

The clinical features of propofol infusion syndrome (PRIS) are acute refractory bradycardia leading to asystole, in the presence of one or more of the following: metabolic acidosis (base deficit > 10 mmol.l(-1)), rhabdomyolysis, hyperlipidaemia, and enlarged or fatty liver. There is an association between PRIS and propofol infusions at doses higher than 4 mg.kg(-1).h(-1) for greater than 48 h duration. Sixty-one patients with PRIS have been recorded in the literature, with deaths in 20 paediatric and 18 adult patients. Seven of these patients (four paediatric and three adult patients) developed PRIS during anaesthesia. It is proposed that the syndrome may be caused by either a direct mitochondrial respiratory chain inhibition or impaired mitochondrial fatty acid metabolism mediated by propofol. An early sign of cardiac instability associated with the syndrome is the development of right bundle branch block with convex-curved ('coved type') ST elevation in the right praecordial leads (V1 to V3) of the electrocardiogram. Predisposing factors include young age, severe critical illness of central nervous system or respiratory origin, exogenous catecholamine or glucocorticoid administration, inadequate carbohydrate intake and subclinical mitochondrial disease. Treatment options are limited. Haemodialysis or haemoperfusion with cardiorespiratory support has been the most successful treatment.

Organ toxicity and mortality in propofol-sedated rabbits under prolonged mechanical ventilation

BACKGROUND

Prolonged administration of propofol at large doses has been implicated in propofol infusion syndrome in intensive care unit patients. In this study we investigated organ toxicity and mortality of propofol sedation at large doses in prolonged mechanically ventilated rabbits and determined the role of propofol's lipid vehicle.

METHODS

Eighteen healthy male rabbits were endotracheally intubated and sedated with propofol 2% (Group P), sevoflurane (Group S) or sevoflurane while receiving Intralipid 10% (Group SI). Sedation lasted 48 h or until death (Group P) or the maximum surviving period of Group P (Groups S and SI). The initial propofol infusion rate (20 mg x kg(-1) x h(-1)) or sevoflurane concentration (1.5%) was adjusted, if needed, to maintain a standard level of sedation. Blood biochemical analysis was performed in serial blood samples and histologic examination in the heart, lungs, liver, gallbladder, kidneys, urinary bladder, and quadriceps femoris muscle at autopsy.

RESULTS

The mortality rate was 100% (surviving period, 26-38 h) for Group P, whereas 0% for Groups S and SI. The initial propofol infusion rate had to be increased up to 65.7 +/- 4.6 mg x kg(-1) x h(-1) and sevoflurane concentration up to 4%. Serum liver function indices, lipids and creatine kinase were significantly increased (P < 0.05) in Groups P and SI and lactate was increased only in Group P, whereas amylase was increased in all groups. In Group P, histologic examination revealed myocarditis, pulmonary edema with interstitial pneumonia, hepatitis, steatosis, and focal liver necrosis, cholangitis, gallbladder necrosis, acute tubular necrosis of the kidneys, focal loss of the urinary bladder epithelium, and rhabdomyolysis of skeletal muscles; in Group S, low-grade bronchitis and incipient inflammation of the liver and the kidneys; and in Group SI, low-grade bronchitis, liver steatosis and hepatitis, and incipient inflammation of the gallbladder, kidneys, and urinary bladder.

CONCLUSIONS

Continuous infusion of 2% propofol at large doses for the sedation of rabbits undergoing prolonged mechanical ventilation induced fatal multiorgan dysfunction syndrome similar to the propofol infusion syndrome seen in humans. Our novel findings including lung, liver, gallbladder, and urinary bladder injury were also noted. The role of propofol's lipid vehicle in the manifestation of the syndrome was minor. Sevoflurane proved to be a safe alternative medication for prolonged sedation.

Sedation and analgesia for brief diagnostic and therapeutic procedures in children

The number of diagnostic and therapeutic procedures done outside of the operating room and the intensive care unit has increased substantially in recent years. In parallel, the management of acute pain and anxiety in children undergoing therapeutic and diagnostic procedures has developed considerably in the past two decades. The primary goal of procedural sedation and analgesia is the safe and efficacious control of emotional distress and pain. The availability of non-invasive monitoring, short-acting opioids and sedatives has broadened the possibilities of sedation and analgesia in children in diverse settings. While most of these procedures themselves pose little risk to the child, the administration of sedation or analgesia may add substantial risk to the patient. This article reviews the current status of sedation and analgesia for invasive and non-invasive procedures in children providing an evidence-based approach to several topics of importance, including patient assessment, personnel requirements, equipment, monitoring, and drugs.

Effects of Propofol and Midazolam on Lipids, Glucose, and Plasma Osmolality during and in the Early Postoperative Period Following Coronary Artery Bypass Graft Surgery: A Randomized Trial

It is not clear how levels of serum lipids and glucose and plasma osmolality change during propofol infusion in the pre- and postoperative period of coronary artery bypass graft surgery (CABG). This prospective, randomized, controlled trial evaluated changes in these parameters during propofol or midazolam infusion during and in the early postoperative period following surgery. Twenty patients undergoing CABG were randomized preoperatively into two groups: 10 patients received propofol (induction 1.5 mg/kg, maintenance 1.5 mg kg(-1) h(-1)) and 10 patients received midazolam (induction 0.5 mg/kg, maintenance 0.1 mg kg(-1) h(-1)). Both groups also received fentanyl (induction 20 mug/kg, maintenance 10 microg kg(-1)). Serum lipids, glucose, and plasma osmolality were measured preinduction, precardiopulmonary bypass, at the end of cardiopulmonary bypass, at the end of surgery, and 4 and 24 h postoperatively. In the propofol group, we observed a significant increase in triglycerides and very low-density lipoprotein levels 4 h postoperatively. In the midazolam group, we observed a significant decrease in low-density lipoprotein, cholesterol at the end of cardiopulmonary bypass, end of surgery, and 4 and 24 h postoperatively and significant increase in osmolality at the end of cardiovascular bypass. Changes in glucose levels did not differ significantly different between the two groups. In patients with normal serum lipids, glucose, and plasma osmolality undergoing CABG, propofol infusion for maintenance anesthesia is not associated with dangerous changes in serum lipids, glucose, and plasma osmolality compared with midazolam. A propofol infusion technique for maintenance of anesthesia for cardiac surgery where serum lipids and glucose may be of concern could be recommended as an alternative to midazolam.

Intraindividual propofol dosage variability in children undergoing repetitive procedural sedations

The authors prospectively assessed intraindividual variability in propofol dosage for induction of sedation in repetitive procedures in children with malignancies. A total of 80 procedures were performed in 24 children. Primary outcome measure was the intraindividual propofol dose required to achieve adequate sedation. Intraindividual variability in propofol dosage required to achieve adequate sedation was 0.0-2.2 mg.kg-1. Twenty-five percent of the patients had a dose range of 0.0-0.5 mg x kg-1; 37.5%, >0.5-1.0 mg x kg-1; and 37.5% >1.0-2.2 mg x kg-1. Due to remarkable intraindividual differences, propofol dosage should be titrated toward the desired level of sedation.

Anesthetic management of a pediatric patient on a ketogenic diet

There are several specific considerations regarding seizure control during the perioperative period in patients who have been placed on a ketogenic diet (KD). A KD is high in fat and low in protein and carbohydrates and has a long history of use for the treatment of intractable seizures in children. Maintaining therapeutic ketosis and modifying the acid-base balance are particularly important for preventing seizures in patients on a KD. We report changes in the biochemical parameters of a patient with double cortex syndrome who was on a KD and who had been scheduled for the treatment of dental caries under sevoflurane anesthesia and acetate Ringer administration. Inhalation induction with a high concentration of sevoflurane should be reconsidered in view of recent reports describing the epileptogenic potential of sevoflurane.