Optimization of Endotracheal Tube Cuff Pressure by Monitoring CO2 Levels in the Subglottic Space in Mechanically Ventilated Patients: A Randomized Controlled Trial.

BACKGROUND: Many of the complications of mechanical ventilation are related to inappropriate endotracheal tube (ETT) cuff pressure. The aim of the current study was to evaluate the effectiveness of automatic cuff pressure closed-loop control in patients under prolonged intubation, where presence of carbon dioxide (CO2) in the subglottic space is used as an indicator for leaks. The primary outcome of the study is leakage around the cuff quantified using the area under the curve (AUC) of CO2 leakage over time. METHODS: This was a multicenter, prospective, randomized controlled, noninferiority trial including intensive care unit patients. All patients were intubated with the AnapnoGuard ETT, which has an extra lumen used to monitor CO2 levels in the subglottic space.The study group was connected to the AnapnoGuard system operating with cuff control adjusted automatically based on subglottic CO2 (automatic group). The control group was connected to the AnapnoGuard system, while cuff pressure was managed manually using a manometer 3 times/d (manual group). The system recorded around cuff CO2 leakage in both groups. RESULTS: Seventy-two patients were recruited and 64 included in the final analysis. The mean hourly around cuff CO2 leak (mm Hg AUC/h) was 0.22 ± 0.32 in the manual group and 0.09 ± 0.04 in the automatic group (P = .01) where the lower bound of the 1-sided 95% confidence interval was 0.05, demonstrating noninferiority (>-0.033). Additionally, the 2-sided 95% confidence interval was 0.010 to 0.196, showing superiority (>0.0) as well. Significant CO2 leakage (CO2 >2 mm Hg) was 0.027 ± 0.057 (mm Hg AUC/h) in the automatic group versus 0.296 ± 0.784 (mm Hg AUC/h) in the manual group (P = .025). In addition, cuff pressures were in the predefined safety range 97.6% of the time in the automatic group compared to 48.2% in the automatic group (P < .001). CONCLUSIONS: This study shows that the automatic cuff pressure group is not only noninferior but also superior compared to the manual cuff pressure group. Thus, the use of automatic cuff pressure control based on subglottic measurements of CO2 levels is an effective method for ETT cuff pressure optimization. The method is safe and can be easily utilized with any intubated patient.

An in vitro and in vivo validation of a novel monitor for intracuff pressure in cuffed endotracheal tubes.

BACKGROUND: The clinical practice of pediatric anesthesiology has changed with increasing use of cuffed endotracheal tubes (cETTs) in infants and children. To limit the risk of tracheal mucosal damage, regular monitoring of intracuff pressure (CP) is necessary. This study evaluates the efficacy and accuracy of a novel syringe device that provides a digital readout of the CP. METHODS: The study was conducted in two phases. In phase 1, an in vitro study, cETTs of sizes 4.0, 5.0, and 6.0 mm ID were placed into polyvinylchloride tubing of appropriate sizes. The cuffs were then inflated, and the CP was measured simultaneously using the syringe device and a manometer. In phase 2, an in vivo study on 200 pediatric patients, the syringe device and the manometer were simultaneously attached to the pilot balloon to measure the CP following endotracheal intubation. Statistical analysis included linear regression analysis and Bland-Altman comparison. RESULTS: Linear regression analysis of the in vitro study demonstrated an R2 value of 0.9989. Bias and precision were -1.92 ± 0.62 with 95% level of agreement (LOA) ranging from -3.13 to -0.72. For the in vivo study, the linear regression analysis demonstrated an R2 value of 0.9943. The bias and precision were -0.53 ± 0.68 with 95% LOA ranging from -1.86 to 0.81. CONCLUSION: The study has demonstrated clinically acceptable correlation between the CPs obtained from the standard manometer and the syringe device both in vitro and in vivo. This device is a simple, reliable, portable, and affordable method to monitor CP.

Changing patterns of hospital length of stay after orthognathic surgery.

PURPOSE: The purpose of this study was to estimate the hospital length of stay (LOS) and identify factors associated with LOS in orthognathic surgery patients. MATERIALS AND METHODS: Using a retrospective cohort study design, we enrolled a sample composed of patients who underwent orthognathic surgery at Massachusetts General Hospital between January 1994 and July 2006. The primary predictor variables were fixation type (rigid/nonrigid), anesthesia technique (hypotensive/normotensive), and perioperative steroid use (yes/no). The outcome variable was LOS. Descriptive statistics were computed for all variables. Bivariate analyses were used to identify factors associated with duration of LOS with P values less than .15. Multiple regression modeling was used to assess the relationship between the primary predictor variables and LOS. The level of statistical significance was set at P less than .05. RESULTS: The study sample was comprised of 627 subjects (58.5% female) with a mean age of 26.1 +/- 10.2 years. The overall mean LOS was 1.7 +/- 1.2 days. During the study period, LOS decreased from 2.3 to 1.3 days (P < .001). In the adjusted multiple regression model, rigid fixation, procedure type, and length of operation were statistically significantly associated with LOS (P < .05). CONCLUSION: The results of this study indicate that individual variables associated with duration of LOS are complexity of the orthognathic procedure and type of fixation used. In the multiple logistic regression model, LOS decreases significantly when rigid fixation, hypotensive anesthesia, and perioperative steroids are used in combination.

Local anesthetic infiltration versus caudal epidural block for anorectal surgery: a randomized controlled trial.

STUDY OBJECTIVE: To compare patient satisfaction with local anesthetic infiltration versus caudal epidural block for anorectal procedures. DESIGN: Randomized controlled trial. SETTING: Operating room and postanesthesia care unit (PACU). PATIENTS: 22 adult, ASA physical status I, II, and III patients scheduled for anorectal surgery. INTERVENTIONS: Patients were randomized to receive either local anesthetic infiltration (LAI) (n = 10) by the surgeon or caudal epidural block (CEB) (n = 12) by the anesthesiologist. MEASUREMENTS: The primary outcome was patient satisfaction with the anesthetic technique and pain relief 12 hours after the procedure on a 4-point Likert scale. Secondary outcomes included time to first analgesic request, time to reach a PACU discharge score (REACT score) of 10, time to ambulation, time to discharge home, and adverse events. MAIN RESULTS: More subjects in the CEB group (83.3%) were highly satisfied than in the LAI group (20%; P = 0.003), assessed 12 hours postoperatively by telephone interview. Subjects in the CEB group requested analgesia 423 minutes later (95% confidence interval, 286-560 min) than subjects in the LAI group. Differences in time to reach a REACT score of 10, time to ambulation, and time to discharge home were not statistically significant. CONCLUSIONS: Caudal epidural block provides higher patient satisfaction and longer lasting analgesia than LAI without delaying discharge.

Safety and efficacy of intranasal ketamine for the treatment of breakthrough pain in patients with chronic pain: a randomized, double-blind, placebo-controlled, crossover study.

Few placebo-controlled trials have investigated the treatment of breakthrough pain (BTP) in patients with chronic pain. We evaluated the efficacy and safety of intranasal ketamine for BTP in a randomized, double-blind, placebo-controlled, crossover trial. Twenty patients with chronic pain and at least two spontaneous BTP episodes daily self-administered up to five doses of intranasal ketamine or placebo at the onset of a spontaneous BTP episode (pain intensity > or =5 on a 0-10 scale). Two BTP episodes at least 48 h apart were treated with either ketamine or placebo. Patients reported significantly lower BTP intensity following intranasal ketamine than after placebo (P < 0.0001) with pain relief within 10 min of dosing and lasting for up to 60 min. No patient in the ketamine group required his/her usual rescue medication to treat the BTP episode, while seven out of 20 (35%) patients in placebo group did (P = 0.0135). Intranasal ketamine was well tolerated with no serious adverse events. After ketamine administration, four patients reported a transient change in taste, one patient reported rhinorrhea, one patient reported nasal passage irritation, and two patients experienced transient elevation in blood pressure. A side effect questionnaire administered 60 min and 24 h after drug or placebo administration elicited no reports of auditory or visual hallucinations. These data suggest that intranasal administration of ketamine provides rapid, safe and effective relief for BTP.

The PediSedate device, a novel approach to pediatric sedation that provides distraction and inhaled nitrous oxide: clinical evaluation in a large case series.

BACKGROUND: Pediatric sedation is of paramount importance but can be challenging. Fear and anticipatory anxiety before invasive procedures often lead to uncooperativeness. A novel device (PediSedate) provides sedation through a combination of inhaled nitrous oxide and distraction (video game). We evaluated the acceptability and safety of the PediSedate device in children. METHODS: We enrolled children between 3 and 9 years old who were scheduled to undergo surgical procedures that required general inhalational anesthesia. After the device was applied, he/she played a video game while listening to the audio portion of the game through the earphones. Nitrous oxide in oxygen was administered via the nasal piece of the headset starting at 50% and increasing to 70%, in 10% increments every 8 min. Treatment failures, vital signs, arterial oxygen saturation, depth of sedation, airway patency, side effects, acceptance of the device and parental satisfaction were all evaluated. RESULTS: Of 100 children included, treatment failure occurred in 18% mainly because of poor tolerance of the device. At least 96% of the children who completed the study exhibited an excellent degree of sedation, 22% had side effects, and none experienced serious airway obstruction. Nausea and vomiting were the most common side effects and no patients had hemodynamic instability. CONCLUSIONS: The PediSedate device combines nonpharmacologic with pharmacologic methods of sedation. Most of the children we evaluated were able to tolerate the PediSedate device and achieved an adequate degree of sedation.

Bispectral index in a 3-year old undergoing deep hypothermia and circulatory arrest.

We report a 3-year-old girl who presented with Scimitar syndrome and underwent hypothermic circulatory arrest for correction of anomalous pulmonary veins and an atrial septal defect. In this case the Bispectral Index (BIS) correlated significantly with the gradual onset of hypothermia and circulatory arrest. However, BIS remained low during the rewarming phase of cardiopulmonary bypass, in spite of adequate pump flows and stable haemodynamics. We postulate that this significant lag in BIS during the rewarming phase of deep hypothermic circulatory arrest may represent neuronal bewilderment or perhaps stunning, and differs from previous studies that show significant increase in BIS during rewarming from mild hypothermia.