[Fospropofol: A new prodrug of propofol]. / Fospropofol: un nuevo profármaco del propofol.

The development of new propofol formulations has advanced rapidly in the last ten years with the achievement of the marketing a new prodrug of propofol: fospropofol, pharmacologically different from the original compound. It is a water soluble compound that requires metabolism of the prodrug to propofol, which leads to a time delay between its administration and the appearance of its pharmacological effect. Its pharmacokinetic and pharmacodynamic characteristics are different to the original formula. Due to its formulation it does not cause pain on intravenous injection, does not lead to hyperlipidaemia or excess bacterial growth. Although it is currently unavailable in Spain, it has been approved by the FDA (American Food and Drug Administration) for sedation in controlled care in diagnostic and therapeutic procedures in adults. It must only be administered by personnel qualified to administer anaesthesia, and the patients must be monitored throughout the whole procedure.

[Fascia iliaca compartment block for analgesia following total hip replacement surgery]. / Bloqueo iliofascial para analgesia postoperatoria de prótesis total de cadera.

OBJECTIVE: The objective of this pilot study was to evaluate the effectiveness of the fascia iliaca compartment block to control pain following total hip replacement by assessing pain intensity 24 hours after surgery and recording the use of opiates for rescue analgesia. MATERIAL AND METHODS: We performed a prospective observational study of 41 patients undergoing total hip replacement surgery. The patients were divided into 2 groups: a group that received a fascia iliaca compartment block with 0.45% ropivacaine at a dosage of 0.3 mL/kg (maximum dose, 30 mL) and a control group in which no block was performed. Patients were enrolled consecutively as they entered the postanesthetic recovery unit. Postoperative pain was assessed on a visual analog scale (VAS) immediately after surgery and 24 hours later. Other variables recorded were opiate use for rescue analgesia and adverse effects due to the use of opiates. RESULTS: The VAS scores recorded in the postanesthetic recovery unit were significantly different in the 2 groups, with lower scores in the group receiving the fascia iliaca compartment block (P < .001). However, no significant between-group differences were observed in VAS scores recorded on the ward 24 hours after surgery (P = .57). CONCLUSIONS: A single-injection fascia iliaca compartment block was effective in controlling initial postoperative pain in a postanesthetic recovery unit. It was effective on the ward in the first few hours after surgery but not for the entire 24-hour period because of the limited duration of the block.

[Propofol: new formulations]. / Propofol: nuevas formulaciones.

Few pharmacologically new anesthetics have appeared in recent years, but great progress has been made toward improving some existing ones. Such is the case with propofol. New formulations have been developed to reduce or avoid adverse side effects associated with the original drug produced by Astra-Zeneca. The unwanted effects for which solutions have been sought are pain upon intravenous injection of the drug, elevated serum concentrations of triglycerides, and the risk of bacterial contamination. Some new formulations contain excipients with bactericidal action, such as propofol with ethylenediaminetetraacetic acid or metabisulfite, and others use lipuro rather than intralipid. Other more advanced products are propofol in cyclodextrin or IDD-D propofol, which makes use of nanoparticle technology. A grasp of the pharmacokinetics and pharmacodynamics of the original formulation must be the basis for understanding the differences between these new products.

Analgesia with interfascial continuous wound infiltration after laparoscopic colon surgery: A randomized clinical trial.

OBJECTIVES: For major laparoscopic surgery, as with open surgery, a multimodal analgesia plan can help to control postoperative pain. Placing a wound catheter intraoperatively following colon surgery could optimize the control of acute pain with less consumption of opioids and few adverse effects. METHODS: We conducted a prospective, randomized, study of patients scheduled to undergo laparoscopic colon surgery for cancer in Galdakao-Usansolo Hospital from January 2012 to January 2013. Patients were recruited and randomly allocated to wound catheter placement plus standard postoperative analgesia or standard postoperative analgesia alone. A physician from the acute pain management unit monitored all patients for pain at multiple points over the first 48 hours after surgery. The primary outcome variables were verbal numeric pain scale scores and amount of intravenous morphine used via patient controlled infusion. RESULTS: 92 patients were included in the study, 43 had a wound catheter implanted and 49 did not. Statistically significant differences in morphine consumption were observed between groups throughout the course of the treatment period. The mean total morphine consumption at the end of the study was 5.63±5.02mg among wound catheter patients and 21. 86±17.88mg among control patients (P=.0001). Wound catheter patients had lower pain scale scores than control patients throughout the observation period. No adverse effects associated with the wound catheter technique were observed. The wound catheter group showed lower hospital stays with statistically significant difference (P=.02). CONCLUSIONS: In patients undergoing laparoscopic colon surgery, continuous infusion of local anaesthetics through interfascial wound catheters during the first 48h aftersurgery reduced the level of perceived pain and also reduced parenteral morphine consumption with no associated adverse effects and lower hospital stays.

Influence of formulation on propofol pharmacokinetics and pharmacodynamics in anesthetized patients.

BACKGROUND: In anesthesia with propofol, variability persists besides sophisticated effect targeting. Drug formulation may be another factor. We have analyzed, retrospectively, the pharmacokinetics (PK) and pharmacodynamics (PD) in monitored surgery patients anesthetized with one each of five formulations of propofol. METHODS: Propofol 1% ('form' 1: Diprivan(Zeneca Limited, Macclesfield, UK), 2: Recofol(Schering Espana, Madrid, Spain), 3: Ivofol(Juste, Madrid, Spain), 4: Propofol Abbott (Abbott Laboratories, Madrid, Spain), 5: Fresenius (Fresenius Kabi Espana, Barcelona, Spain)) was administered to 77 ASA I-II patients of age [mean (range) 44 (18-65) years]. Induction of anesthesia was with varying propofol doses up to endpoints of either 60 on the Bispectral Index system (BIS) in group I (n = 48, model development) or standard clinical signs in group II (n = 29, validation). Maintenance was with three 10-min infusions of 10, 8 and 6 mg kg(-1) h(-1). Three blood samples were obtained from each subject, immediately after induction, and at 15 and 30 min on maintenance, with BIS and hemodynamic variables recorded at these times also. Total and free blood concentrations (Cb) of propofol were determined with HPLC. Pharmacokinetic and PD models with link equilibration rate ke0, were studied with a mixed-effects procedure (NONMEM). RESULTS: The induction dose (group I) showed large interindividual variability [mean (range) 163 (90-290 mg)] that correlated significantly with age, basal systolic blood pressure and formulation. The PK of propofol (basic model) was described by a one-compartment model with (typical value [interindividual coefficient of variation percent (CV%)]) CL=2.30 l min(-1) (27%) and V=8.40 l (80%). Weight (WT) and formulation, within NONMEM, were found to be significant covariates for CL and V, reducing their CV% to 25% and 74%, respectively. The final PK/PD model, which includes formulation, showed a 50% reduction in the CV% for both the ke0 and the residual error. This PK/PD model was validated in group II with 33% precision and no bias. CONCLUSION: The PK and PD are not equal for all formulations, which contributes to an increase in variability of the observed effect.