Induction of anaesthesia with remifentanil after bolus midazolam administration in Landrace/Large White swine.

OBJECTIVE: To investigate an alternative combination for anaesthesia induction in swine. STUDY DESIGN: Randomized, 'blinded' experimental study. ANIMALS: Forty-five Landrace/Large White swine weighing 20.0±1.5 kg. METHODS: Pulse oximetry, heart rate (HR) and blood pressure were measured after premedication with ketamine, midazolam and atropine as well as after intubation following induction with a fixed dose of 0.2 mg kg-1 midazolam combined with 1, 2, 3, 4 or 5 µg kg-1 remifentanil (groups R1, R2, R3, R4 and R5, respectively). Intubation was evaluated using a numerical scoring system assessing jaw relaxation, resistance to the laryngoscope, vocal cord position, vocal cord movement and response to intubation. The time required to intubate and necessity for an additional midazolam dose were recorded. Baseline and post-intubation variables were compared with paired t tests, whereas for differences between the remifentanil groups the Spearman's rank correlation coefficient was estimated. Multivariate regression analysis was performed to disentangle the effect of remifentanil dose and the additional midazolam. RESULTS: Higher dose of remifentanil was associated with better vocal cord position (p<0.001), better response to intubation (p<0.001), shorter time required for intubation (p=0.030) and less frequent necessity for additional administration of midazolam (p=0.004). In total, 39.5% of the animals required additional midazolam. In groups R1, R4 and R5, there were decreases in HRs (p=0.009, p=0.008 and p=0.032, respectively) between baseline and post-intubation phase; in groups R3 and R4, there were decreases in systolic blood pressure (p=0.040 and p=0.019, respectively). In the multivariate analysis, remifentanil dose was not associated with the observed changes in haemodynamic variables. One animal developed apnoea and four electrocardiographic anomalies; all resolved without pharmaceutical interventions. CONCLUSIONS AND CLINICAL RELEVANCE: A combination of 0.2 mg kg-1 midazolam with 4 or 5 µg kg-1 remifentanil may provide an alternative method of anaesthesia induction for swine.

Refined induction of anesthesia with remifentanil after bolus propofol administration in Landrace/Large White swine.

The authors report a prospective randomized blind study in which they used a refined anesthetic technique in male Landrace/Large White swine (n = 125 pigs, 19 ± 2 kg, 10-15 weeks old). The animals were first premedicated with ketamine, midazolam and atropine and then given a dose of 1, 2, 3, 4 or 5 µg remifentanil per kg body weight (dose amounts were randomly assigned) after a bolus dose of propofol. The authors assessed the intubation conditions (e.g., jaw relaxation and other parameters) 20 min after premedication and then 5 min after anesthesia induction. All animals that received each of the different remifentanil dose amounts were successfully intubated in less than 30 s. No animal developed apnea during intubation or experienced substantial reductions in heart rate or blood pressure (> 25%) between the two time points (20 min after premedication and 5 min after anesthesia induction). Overall intubation conditions were significantly better in animals that received 5 µg remifentanil per kg body weight than in animals that received other dose amounts (P < 0.001). The average time to intubation was significantly shorter for animals that received 5 µg remifentanil per kg body weight than for animals that received any of the other dose amounts (P < 0.001). The authors concluded that for this study, 5 µg remifentanil per kg body weight resulted in excellent intubating conditions in this swine breed.

Towards long-acting adrenaline for cardiopulmonary resuscitation: Production and characterization of a liposomal formulation.

The use of adrenaline in cardiopulmonary resuscitation is a long-standing medical procedure, recommended by several international guidelines. However, its unspecific action on adrenergic receptors and the need for repeated administrations pose serious concerns about its safety, the balance between benefits and risks being still under debate. To address this issue, a sustained release nano-formulation of adrenaline was developed. Adrenaline was encapsulated into PEGylated, anionic liposomes by a pH-driven loading technique. Particular attention was devoted to the prevention of oxidation of adrenaline by optimizing the preparative process and including an optimal amount of antioxidants in the formulation. The vesicles obtained were then characterized for size, zeta-potential, and lamellarity, while their morphology was described by cryo-TEM. The controlled release properties were confirmed by two different in vitro release-testing methods, and the biocompatibility was assayed on human endothelial cells in vitro.

Cardiopulmonary resuscitation: a historical perspective leading up to the end of the 19th century.

Social laws and religious beliefs throughout history underscore the leaps and bounds that the science of resuscitation has achieved from ancient times until today. The effort to resuscitate victims goes back to ancient history, where death was considered a special form of sleep or an act of God. Biblical accounts of resuscitation attempts are numerous. Resuscitation in the Middle Ages was forbidden, but later during Renaissance, any prohibition against performing cardiopulmonary resuscitation (CPR) was challenged, which finally led to the Enlightenment, where scholars attempted to scientifically solve the problem of sudden death. It was then that the various components of CPR (ventilation, circulation, electricity, and organization of emergency medical services) began to take shape. The 19th century gave way to hallmarks both in the ventilatory support (intubation innovations and the artificial respirator) and the open-and closed chest circulatory support. Meanwhile, novel defibrillation techniques had been employed and ventricular fibrillation described. The groundbreaking discoveries of the 20th century finally led to the scientific framework of CPR. In 1960, mouth-to-mouth resuscitation was eventually combined with chest compression and defibrillation to become CPR as we now know it. This review presents the scientific milestones behind one of medicine's most widely used fields.

Inexperienced nurses and doctors are equally efficient in managing the airway in a manikin model.

OBJECTIVE: The aim of the present study was to investigate whether minimally trained medical and nursing school graduates would be equally efficient in placing a laryngeal mask airway (LMA) and in intubating the trachea with the Macintosh blade or a videolaryngoscope in a manikin model. Airway management is an essential skill for both physicians and nurses who may be confronted with a critically ill patient, because in the emergency department the airway is not exclusively managed by medical personnel. Several studies have shown that other healthcare professionals are not any less efficient in securing the airway. METHODS: Ninety-six graduates from medical and nursing faculties comprised our study population. After a brief educational session, participants were randomly allocated into 3 groups to secure the airway in manikins with 3 techniques: LMA (The Laryngeal Mask Company Limited, Buckinghamshire, UK) insertion and intubation with the Macintosh blade and with a videolaryngoscope (GlideScope, Verathon Inc, Bothell, WA). The number of attempts until the first successful intubation, time required for the first successful attempt, and severity of dental trauma were assessed. RESULTS: No statistically significant difference was observed between physicians and nurses in the number of attempts and in the time required for the first successful attempt with any of the 3 techniques studied. From the 3 techniques studied, LMA placement was the fastest (P < .001). No significant difference was observed between physicians and nurses in the severity of dental trauma. CONCLUSION: Nurses are as efficient as physicians in managing the airway safely and adequately with the 3 different techniques in manikins.

Glidescope(®) videolaryngoscope improves intubation success rate in cardiac arrest scenarios without chest compressions interruption: a randomized cross-over manikin study.

AIM: The aim of this study was to assess the performance of the Glidescope(®) in a manikin cardiopulmonary resuscitation (CPR) scenario. METHODS: Following a brief didactic session, 45 volunteer doctors inexperienced with airway management, attempted to intubate a manikin using a Macintosh laryngoscope and Glidescope(®) with uninterrupted and without chest compressions. Primary endpoints were intubation times and success rate with each device. Dental compression and level of self-confidence in using each device were also assessed. RESULTS: In the scenario without chest compressions the cumulative success rate related to time to intubation was significantly higher with the Macintosh blade than with the Glidescope(®) (p<0.001). On the contrary, in the scenario with continuous chest compressions, the cumulative rate related to time to intubation was significantly higher with the Glidescope(®) (p=0.035). Significantly fewer attempts were required for the first successful intubation with the Macintosh blade in the non-CPR scenario versus the CPR scenario (p=0.007). Moreover, the number of attempts for the first successful intubation was significantly lower for the Glidescope(®) in the non-CPR (p=0.001) and the CPR scenario (p<0.001). Dental compression was significantly lower with the Glidescope(®) in both scenarios (p<0.001). CONCLUSIONS: Using the GlideScope(®) in a manikin CPR scenario provides extremely high intubation success rates in short times with the first attempt, in medical practitioners inexperienced in intubation.