A Positive Cocaine Urine Toxicology Test and the Effect on Intraoperative Hemodynamics Under General Anesthesia.

BACKGROUND: Cocaine has a short biological half-life, but inactive urine metabolites may be detectable for a week following use. It is unclear if patients who test positive for cocaine but have a normal electrocardiogram and vital signs have a greater percentage of hemodynamic events intraoperatively. METHODS: A total of 328 patients with a history of cocaine use who were scheduled for elective noncardiac surgery under general anesthesia were enrolled. Patients were categorized into cocaine-positive versus cocaine-negative groups based on the results of their urine cocaine toxicology test. The primary aim of this study was to evaluate whether asymptomatic cocaine-positive patients had similar percentages of intraoperative hemodynamic events, defined as (1) a mean arterial blood pressure (MAP) of <65 or >105 mm Hg and (2) a heart rate (HR) of <50 or >100 beats per minute (bpm) compared to cocaine-negative patients. The study was powered to assess if the 2 groups had an equivalent mean percent of intraoperative hemodynamic events within specific limits using an equivalence test of means consisting of 2 one-sided tests. RESULTS: The cocaine-positive group had a blood pressure (BP) that was outside the set limits 19.4% (standard deviation [SD] 17.7%) of the time versus 23.1% (SD 17.7%) in the cocaine-negative group (95% confidence interval [CI], 0.5-7.0). The cocaine-positive group had a HR outside the set limits 9.6% (SD 16.2%) of the time versus 8.2% (SD 14.9%) in the cocaine-negative group (95% CI, 4.3-1.5). Adjusted for age, sex, body mass index (BMI), smoking status, and the presence of comorbid hypertension, renal disease, and psychiatric illness, the cocaine-positive and cocaine-negative patients were similar within a 7.5% margin of equivalence for MAP data (ß coefficient = 2%, P = .003, CI, 2-6) and within a 5% margin of equivalence for HR data (ß coefficient = 0.2%, P < .001, CI, 4-3). CONCLUSIONS: Asymptomatic cocaine-positive patients undergoing elective noncardiac surgery under general anesthesia have similar percentages of intraoperative hemodynamic events compared to cocaine-negative patients.

The influence of morbid obesity on difficult intubation and difficult mask ventilation.

PURPOSE: To determine the influence of morbid obesity on the incidence of difficult mask ventilation and difficult intubation. METHODS: Over a 6-year period, all tracheal intubations in the operating room of a large tertiary teaching hospital were analyzed. A modified version of the intubation difficulty scale (mIDS) was used to define easy versus difficult intubation, where a score of two or greater was defined as difficult intubation. Difficult mask ventilation was defined as the use of one or more adjuncts to achieve successful mask ventilation. RESULTS: Of 45,447 analyzed cases, 1893 (4.2%) were classified as difficult intubations. Morbidly obese patients were not more likely to have difficult intubation [Odds Ratio (OR) = 1.131, 95% confidence interval (CI): 0.958, 1.334, p = 0.146]. Factors that were associated with difficult intubation included patient age > 46 years, male sex, Mallampati 3-4, thyromental distance < 6 cm, and the presence of intact dentition. Of 37,016 cases in which mask ventilation was attempted, 1069 (2.9%) were difficult. Morbidly obese patients were more likely to have difficult mask ventilation (OR = 3.785, 95% CI: 3.188, 4.493, p < 0.0001). Other factors associated with difficult mask ventilation included patient age > 46 years, male sex, Mallampati 3-4, and a history of obstructive sleep apnea. Having intact dentition decreased the likelihood of difficult mask ventilation. CONCLUSION: Morbidly obese patients do not have a higher incidence of difficult intubation compared to non-morbidly obese patients. However, they have a significantly higher incidence of difficult mask ventilation. Other factors that are predictive of both difficult mask ventilation and difficult intubation include age > 46 years, male sex, and Mallampati 3-4.

Recent cocaine use and the incidence of hemodynamic events during general anesthesia: A retrospective cohort study.

STUDY OBJECTIVE: To evaluate the intraoperative hemodynamics and medication requirements of cocaine-positive patients compared to matched cocaine-negative controls. DESIGN: Retrospective cohort study. SETTING: Public county hospital. PATIENTS: 821 patients undergoing general anesthesia. MEASUREMENTS: Incidence of hemodynamic events, defined by a mean arterial pressure of <65 mmHg or >105 mmHg or a heart rate of <50 beats per minute or >100 beats per minute. MAIN RESULTS: Cocaine-positive patients did not experience a higher incidence of hemodynamic events when compared with matched cocaine-negative patients. Cocaine-positive patients were not more likely to be administered vasopressors intraoperatively but did receive more anti-hypertensive agents. The minimum alveolar concentration of anesthetics used was similar between the two groups. Anesthesia duration, length of stay, and in-hospital mortality did not significantly differ between the two cohorts. CONCLUSIONS: Cocaine-positive patients did not demonstrate more intraoperative hemodynamic events or adverse short-term outcomes as compared to matched cocaine-negative controls.

Apneic Oxygenation During Prolonged Laryngoscopy in Obese Patients: a Randomized, Double-Blinded, Controlled Trial of Nasal Cannula Oxygen Administration.

BACKGROUND: Obese patients have a propensity to desaturate during induction of general anesthesia secondary to their reduced functional residual capacity and increased oxygen consumption. Apneic oxygenation can provide supplemental oxygen to the alveoli, even in the absence of ventilation, during attempts to secure the airway. In this study, we hypothesized that oxygen administration through a nasopharyngeal airway and standard nasal cannula during a simulated prolonged laryngoscopy would significantly prolong the safe apneic duration in obese patients. METHODS: One hundred thirty-five obese patients undergoing non-emergent surgery requiring general anesthesia were randomized to either the control group or to receive apneic oxygenation with air versus oxygen. All patients underwent a standard intravenous induction. For patients randomized to receive apneic oxygenation, a nasopharyngeal airway and standard nasal cannula were inserted. A simulated prolonged laryngoscopy was performed to determine the duration of the safe apneic period, defined as the beginning of laryngoscopy until the peripheral oxygen saturation (SpO2) reached 95%. RESULTS: The oxygen group had a median safe apneic duration that was 103 s longer than the control group. The lowest mean SpO2 value during the induction period was 3.8% higher in the oxygen group compared to the control group. Following intubation, patients in the oxygen group had a mean end tidal carbon dioxide (ETCO2) level that was 3.0 mmHg higher than patients in the control group. CONCLUSIONS: In obese patients, oxygen insufflation at 15 L/min through a nasopharyngeal airway and standard nasal cannula can significantly increase the safe apneic duration during induction of anesthesia.

Improving the quality of the operating room to intensive care unit handover at an urban teaching hospital through a bundled intervention.

STUDY OBJECTIVE: To evaluate the efficacy of a bundled intervention to improve the quality of the operating room to intensive care unit (ICU) clinical handover. DESIGN: Prospective, interventional study. SETTING: An urban, public teaching hospital with more than 1500 direct postoperative ICU admissions each year. INTERVENTIONS: A bundled intervention to include the addition of a direct anesthesia provider to ICU nurse telephone report, a mnemonic to standardize the handover process, and improved template for postoperative documentation by the anesthesia team. MEASUREMENTS: Preintervention (baseline) and postintervention survey data were solicited from key stakeholders, which included anesthesia providers and ICU nursing staff. MAIN RESULTS: Anesthesia provider and ICU nursing staff satisfaction levels rose significantly following implementation of the bundled intervention. In addition, perceived effectiveness of the handover process and note increased significantly. The satisfaction level of the ICU nurses with respect to the phone report received before patient arrival in the ICU nearly doubled. CONCLUSIONS: The implementation of a bundled handover intervention was associated with increased stakeholder satisfaction as well as a perception of increased efficacy and quality of the overall handover process and postoperative anesthesia documentation.