[Percutaneous or surgical trachetomy. Prospective, randomized comparison of the incidence of early and late complications]. / Tracheotomia percutanea e chirurgica. Confronto prospettico, randomizzato dell'incidenza di complicanze precoci e tardive.

BACKGROUND: To compare early and late complications after either conventional surgical or percutaneous dilatational tracheostomy. DESIGN: Prospective, randomized study. SETTING: General intensive care unit and neuro-surgical intensive care unit in a university hospital. PATIENTS: 50 consecutive patients, requiring tracheostomy for prolonged mechanical ventilation. INTERVENTIONS AND MEASUREMENTS: Patients were randomly allocated to receive either surgical (surgical group, n = 25) or percutaneous dilatational tracheostomy (percutaneous group, n = 25). Occurrence of perioperative complication were carefully evaluated during ICU stay. Late complications were evaluated with both physical and endoscopic examination at 1, 3 to 6 months after tracheostomy. RESULTS: All surgical and percutaneous tracheostomies were successfully completed and no deaths directly related to the tracheostomy procedures were reported. Completion of the procedure required 41 +/- 14 min in the surgical group and 14 +/- 6 min in the percutaneous one (p < 0.0001). The incidence of early perioperative complications was higher in the surgical group (36%) than in percutaneous one (12%), (p < 0.05). The endoscopic follow-up demonstrated one segmental malacia and one stenosis of the trachea in the percutaneous group only (p = n.s.). Skin repair was better after percutaneous tracheostomy than in the surgical group (p < 0.01). CONCLUSIONS: In experienced hands, percutaneous dilatational tracheostomy is as safe and effective as the conventional surgical tracheostomy. The percutaneous technique is less time-consuming and has a lower rate of early infectious complications with better cosmetic results than the surgical technique.

Frequency of hypotension during conventional or asymmetric hyperbaric spinal block.

BACKGROUND AND OBJECTIVES: The purpose of this randomized, double-blind study was to evaluate if use of an asymmetric spinal block affects the incidence of hypotension during spinal anesthesia. METHODS: With Ethical Committee approval and patient consent, 120 patients undergoing lower limb surgery were placed in the lateral position with the side to be operated on dependent, and received 8 mg 0.5% hyperbaric bupivacaine through a 25-gauge Whitacre spinal needle. Patients were randomized to one of two groups: (a) local anesthetic was injected with barbotage through a cranially directed needle orifice, then patients were immediately turned to supine (conventional, n = 60); (b) local anesthetic was injected without barbotage with the needle orifice turned toward the dependent side, then the lateral position was maintained for 15 minutes (unilateral, n = 60). A blind observer recorded noninvasive hemodynamic variables, as well as loss of cold and pinprick sensation and motor block on both sides. RESULTS: In the unilateral group, 31 patients (52%) showed a unilateral loss of cold sensation and 48 patients (80%) had no motor block on the nondependent side for the duration of the study, whereas all conventional patients had bilateral distribution of spinal block (P < .0001). The onset time and two-segment regression of sensory block on the dependent side were more rapid in the conventional group (18 +/- 7 minutes and 60 +/- 18 minutes) than in the unilateral group (22 +/- 8 minutes and 67 +/- 19 minutes) (P < .05 and P < .05, respectively). The incidence of hypotension (SAP decrease >30% from baseline) was higher in the conventional (22.4%) than unilateral group (5%) (P < .01). The maximum percentage changes from baseline values of systolic arterial blood pressure and heart rate were greater in conventional group (-28% +/- 16% and -19% +/- 10%) than in unilateral group (-8% +/- 16% and -12% +/- 18%) (P < .0001 and P < .01, respectively). CONCLUSIONS: Achieving an asymmetric distribution of spinal block by injecting a small dose of 0.5% hyperbaric bupivacaine through a Whitacre spinal needle into patients placed in the lateral position for 15 min reduces the incidence of hypotension during spinal anesthesia.

Clinical assessment of target-controlled infusion of propofol during monitored anesthesia care.

PURPOSE: To determine the plasma concentrations of propofol required to achieve different levels of sedation during monitored anesthesia care. METHODS: Sixty ASA I-II, 18-65 yr-old patients, received a target-controlled continuous iv infusion of propofol. The target plasma concentration of propofol (Cpt) was initially set at 0.4 microg x ml(-1). Two minutes after calculated equilibrium between plasma and effect-site concentrations, the Cpt of propofol was increased by 0.2 microg x ml(-1) steps until the patient showed no reaction to squeezing the trapezius. The level of sedation was assessed immediately before each increase in propofol Cpt using the Observer's Assessment of Alertness/Sedation (OAA/S) scale. RESULTS: The Cpt of propofol required to induce lethargic response to name was 1.3 microg x ml(-1) (5 degrees and 95 degrees percentiles: 1.0 - 1.8 microg x ml(-1)), to obtain response after loud and repeated calling name was 1.7 microg x ml(-1) (1.2 - 2.2 microg x ml(-1)), to obtain response after prodding or shaking was 2.0 microg x ml(-1) (1.6 - 2.6 microg x ml(-1)), to obtain response after squeezing the trapezius was 2.4 microg x ml(-1) (1.8 - 3.0 microg x ml(-1)). Patients showed no response after squeezing the trapezius at 2.8 microg x ml(-1) (2.0 - 3.6 microg x ml(-1)). Correlation between Cpt propofol and sedation scores were r = 0.76, P < 0.0001. CONCLUSIONS: Target-controlled infusion of propofol provided easy and safe management of intraoperative sedation, allowing fast and predictable deepening in the level of sedation, while minimizing systemic side effects of intravenous sedation due to the minimal risk of overdosing the drug.

The target plasma concentration of propofol required to place laryngeal mask versus cuffed oropharyngeal airway.

UNLABELLED: To determine the target plasma concentration of propofol required to place either a laryngeal mask airway (LMA) or a cuffed oropharyngeal airway (COPA), we started a continuous target-controlled infusion of propofol in 60 ASA physical status I or II unpremedicated patients scheduled for minor orthopedic surgery with peripheral nerve block. The target plasma concentration of propofol was initially set at 2 microg/mL. When the effect-site calculated concentration of propofol was equal to the plasma concentration according to the computer simulation, the target plasma concentration was increased by 0.5-microg/mL steps until successful placement of either the LMA (n = 30) or the COPA (n = 30). The mean target plasma concentration of propofol required to place a LMA was 4.3 +/- 0.8 microg/mL compared with 3.2 +/- 0.6 microg/mL to place a COPA (P < 0.001). To successfully place the airways in 95% of patients, the target plasma concentration of propofol had to be increased up to 4 microg/mL for the COPA and 6 microg/mL for the LMA. We conclude that placing a LMA in healthy, unpremedicated patients requires target plasma concentrations of propofol higher than those required for placing a COPA. IMPLICATIONS: We evaluated the use of target-controlled infusion of propofol to place extratracheal airways in this prospective, randomized study and demonstrated that the target plasma concentration of propofol required to successfully place a laryngeal mask in >95% of healthy, unpremedicated patients is 6 microg/mL, compared with 4 microg/mL to place a cuffed oropharyngeal airway.

Do we need new supraglottic devices? Clinical appraisal of the cuffed oropharyngeal airway (COPA)

BACKGROUND: The laryngeal mask airway (LMA) has been widely studied for both conventional and nonconventional uses, while the literature on the cuffed oropharyngeal airway (COPA) is still limited. The purpose of this manuscript was to review the initial appraisal of efficacy, safety, effects on hemodynamics and respiratory function, induction agents and drug requirements of this new supraglottic device. METHODS: We reviewed main results of studies recently published on peer reviewed journals concerning the clinical uses of COPA. RESULTS: When used in healthy adults undergoing general anesthesia for routine minor procedures, the COPA and LMA are substantially equivalent. The LMA is associated with a higher first-time placement rate and fewer manipulations during usage, but the incidence of airway untoward events during COPA anesthesia is equivalent to that reported when using an LMA. The quality of breathing and capnography during COPA ventilation is similar to that provided by the LMA ventilation, with clinically relevant decrease in the physiological deadspace/tidal volume ratio and arterial to end-tidal CO2 tension difference compared with facemask ventilation. In selected patients without risk factors for regurgitation of gastric content, positive-pressure ventilation is similarly successful and safe with the COPA as with the LMA. The COPA seems to be less stimulating than LMA because it has been demonstrated to cause a lower incidence of pharyngeal trauma and sore throat in the immediate postoperative period, requires shorter exposure to an inhalational anesthetic and lower concentrations of propofol to be successfully placed, and is associated with lower effects on the patient's hemodynamic homeostasis than LMA. CONCLUSIONS: More extensive clinical evaluations should be advocated to better understand the risk/benefit ratio of this new supraglottic device; however, it may be concluded that in healthy adults receiving general anesthesia for short procedures the COPA allows for an effective and safe control of the patient's airway and ventilation.

Effects of spinal needle type on lateral distribution of 0.5% hyperbaric bupivacaine.

UNLABELLED: To evaluate the influence of needle type on the lateral distribution of 0.5% hyperbaric bupivacaine, 30 patients undergoing lower limb surgery were placed in the lateral position with the side to be operated on dependent and underwent dural puncture by either a 25-gauge Whitacre (n = 15) or a 25-gauge Quincke (n = 15) spinal needle. The needle hole was turned toward the dependent side and 8 mg of 0.5% hyperbaric bupivacaine was injected over 30 s. The lateral position was maintained for 15 min while a blind observer recorded loss of pinprick sensation and degree of motor block on both the dependent and nondependent sides every 5 min until regression of motor block by 1 degree on the dependent side. Thirty minutes after the patients were placed in the supine position, unilateral sensory block was observed in 10 patients in the Whitacre group (66%) and in 2 patients in the Quincke group (13%) (P < 0.05). No differences in the rate of unilateral motor block were observed (73% and 40% in Whitacre and Quincke groups, respectively). We conclude that when a small dose of 0.5% hyperbaric bupivacaine is injected slowly into patients in the lateral position for 15 min, the Whitacre spinal needle provides a more marked differential block of sensory nerve roots between dependent and nondependent sides compared with the Quincke needle. IMPLICATIONS: Because unilateral spinal anesthesia can be advantageous for lower limb surgery, we evaluated the influence of the Whitacre and Quincke spinal needle types on the lateral distribution of small-dose 0.5% hyperbaric bupivacaine injected slowly into adult patients.