Safety of sedation for gastrointestinal endoscopy in a group of university-affiliated hospitals: a prospective cohort study.

BACKGROUND: Service models for gastrointestinal endoscopy sedation must be safe, as endoscopy is the most common procedure performed under sedation in many countries. The aim of this prospective cohort study was to determine the patient risk profile, and incidence of and risk factors for significant unplanned events, in adult patients presenting for gastrointestinal endoscopy in a group of university-affiliated hospitals where most sedation is managed by anaesthetists. METHODS: Patients aged ≥18 yr presenting for elective and emergency gastrointestinal endoscopy under anaesthetist-managed sedation at nine hospitals affiliated with the University of Melbourne, Australia, were included. Outcomes included significant airway obstruction, hypoxia, hypotension and bradycardia; unplanned tracheal intubation; abandoned procedure; advanced life support; prolonged post-procedure stay; unplanned over-night admission and 30-day mortality. RESULTS: 2,132 patients were included. Fifty percent of patients were aged >60 yr, 50% had a BMI >27 kg m -2, 42% were ASA physical status III-V and 17% were emergency patients. The incidence of significant unplanned events was 23.0% (including significant hypotension 11.8%). Significant unplanned intraoperative events were associated with increasing age, BMI <18.5 kg m -2, ASA physical status III-V, colonoscopy and planned tracheal intubation. Thirty-day mortality was 1.2% (0.2% in electives and 6.0% in emergencies) and was associated with ASA physical status IV-V and emergency status. CONCLUSIONS: Patients presenting for gastrointestinal endoscopy at a group of public university-affiliated hospitals where most sedation is managed by anaesthetists, had a high risk profile and a substantial incidence of significant unplanned intraoperative events and 30-day mortality.

Financial and environmental costs of manual versus automated control of end-tidal gas concentrations.

Emerging technologies that reduce the economic and environmental costs of anaesthesia have had limited assessment. We hypothesised that automated control of end-tidal gases, a new feature in anaesthesia machines, will consistently reduce volatile agent consumption cost and greenhouse gas emissions. As part of the planned replacement of anaesthesia machines in a tertiary hospital, we performed a prospective before and after study comparing the cost and greenhouse gas emissions of isoflurane, sevoflurane and desflurane when using manual versus automated control of end-tidal gases. We analysed 3675 general anaesthesia cases with inhalational agents: 1865 using manual control and 1810 using automated control. Volatile agent cost was $18.87/hour using manual control and $13.82/hour using automated control: mean decrease $5.05/hour (95% confidence interval: $0.88-9.22/hour, P=0.0243). The 100-year global warming potential decreased from 23.2 kg/hour of carbon dioxide equivalents to 13.0 kg/hour: mean decrease 10.2 kg/hour (95% confidence interval: 2.7-17.7 kg/hour, P=0.0179). Automated control reduced costs by 27%. Greenhouse gas emissions decreased by 44%, a greater than expected decrease facilitated by a proportional reduction in desflurane use. Automated control of end-tidal gases increases participation in low flow anaesthesia with economic and environmental benefits.

Night-shift discharge from intensive care unit increases the mortality-risk of ICU survivors.

UNLABELLED: Intensive Care (ICU) survivors discharged from ICU to the general ward at night have a higher mortality. We sought to clarify which factors, including night-shift discharge, influence outcome following ICU discharge in a metropolitan hospital, using a cohort study of critically-ill patients between 1/1/1999-30/4/2003. Patients were excluded from analysis if they (a) died in ICU, (b) were transferred to another hospital, (c) had an ICU length of stay <8 hours, or (d) age <16 years. Logistic regression was used to derive a predictive model based on the following variables: patient demographics, severity of illness following ICU admission (APACHE II mortality-risk, p(m)), final diagnosis, discharge timing including premature or delayed (>4 hours) ICU discharge, and "limitation of medical treatment" orders. The outcome measures were patient status at hospital discharge and ICU readmission rate. Of the 1870 ICU survivors, 92 (4.9%) died after discharge from ICU. Patients discharged to the ward during the night-shift (2200-0730 hours) had a higher APACHE II score and crude mortality. The difference in APACHE II p(m) did not reach statistical significance. No significant calendar or seasonal pattern was identified. Logistic regression identified night-shift discharge (RR=1.7; 95% CI 1.03-2.9; P=0.03), limited medical treatment order (RR=5.1; 95% CI 2.2-12) and admission APACHE II p(m) (RR=3.3; 95% CI 1.3-7.6) as independent predictors of patient outcome following ICU transfer to the ward. CONCLUSION: At the time of ICU discharge to the ward three factors are predictive of hospital outcome: timing of ICU discharge, limited medical treatment orders and initial illness severity.

Anaphylaxis to intravenous amiodarone.

Amiodarone, a class III antiarrhythmic, has been widely used to treat both ventricular and supraventricular arrhythmias. Despite the multitude of side-effects seen with this drug, no case of amiodarone anaphylaxis (confirmed by mast cell tryptase levels and skin testing) has been reported in the medical literature. We report a case of anaphylaxis to intravenous amiodarone in a 77-year-old patient.

Survival of critically ill medical patients is time-critical.

OBJECTIVE: Survival from acute coronary syndromes and major trauma has been shown to depend on timely access to definitive treatment. We sought to identify the significance of intensive care unit (ICU) admission delay (lead-time) on the outcome of critically-ill medical patients with other diagnoses. METHODS: From 1 January 1997 to 31 December 2003, a prospective cohort study was performed in critically-ill patients requiring mechanical ventilatory support (MV) and/or renal replacement therapy (RRT), admitted directly to the Northern Hospital ICU within 24 hours of arrival in the emergency department (ED). Patients were excluded if, a) they were admitted following surgery, major trauma or transfer from another hospital, or b) their duration of ICU stay was < 8 hours. Data collected included de-identified patient demographics, final diagnosis, APACHE II mortality risk (pm) and lead-time (i.e. difference between times of entrance to the ED and ICU.) The primary outcome measure was hospital discharge status. RESULTS: Six hundred and nineteen consecutive ICU admissions from the ED met the inclusion criteria and required MV (n = 557) and/or RRT (n = 162.) Non-survivors were older (median age 73 vs. 54 yrs) and sicker (median pm 0.72 vs. 0.23) compared with survivors. Multivariate analysis using logistic regression identified lead-time as a significant predictor of mortality (RR = 1.06 per hour, 95% CI =1.01 - 1.10; p=0.015) in addition to age, diagnosis and illness severity. CONCLUSIONS: ICU admission delay (lead-time) is associated with a greater mortality-risk in critically ill medical patients requiring MV and/or RRT.

Renal support in critically ill patients: low-dose dopamine or low-dose dobutamine?

OBJECTIVE: Low-dose dopamine has been used in critically ill patients to minimize renal dysfunction without sufficient data to support its use. The aim of this study was to determine whether low-dose dopamine improves renal function, and whether dobutamine, a nondopaminergic inotrope, improves renal function. DESIGN: Prospective, randomized, double-blind trial. PATIENTS: Twenty-three patients at risk for renal dysfunction were entered into the study. Five patients were later withdrawn. Study data for the remaining 18 patients were: mean age 55 yrs; mean Acute Physiology and Chronic Health Evaluation (APACHE) II score of 18; mean weight 71 kg). The following conditions were present: mechanical ventilation (n = 17 [inverse-ratio ventilation, n = 6]); inotrope administration (n = 11); sepsis (n = 13); and adult respiratory distress syndrome or multiple organ failure syndrome (n = 9). INTERVENTIONS: The study patients were administered dopamine (200 micrograms/min), dobutamine (175 micrograms/min), and placebo (5% dextrose) over 5 hrs each in a randomized order. Ventilator settings, fluid management, and preexisting inotropic support were not altered during the study. MEASUREMENTS AND MAIN RESULTS: Systemic hemodynamic values and indices of renal function (4-hr urine volume, fractional excretion of sodium, and creatinine clearance) were measured during the last 4 hrs of each infusion. Dopamine produced a diuresis (145 +/- 148 mL/hr) compared with placebo (90 +/- 44 mL/hr; p < .01) without a change in creatinine clearance. Conversely, dobutamine caused a significant increase in creatinine clearance (97 +/- 54 mL/min) compared with placebo (79 +/- 38 mL/min; p < .01), without an increase in urine output. CONCLUSIONS: In stable critically ill patients, dopamine acted primarily as a diuretic and did not improve creatinine clearance. Dobutamine improved creatinine clearance without a significant change in urine output.

The anatomy of the philtrum: observations made on dissections in the normal lip.

Cadaver dissections and histological studies were performed on the philtral region of eight adults and four foetal lips to elucidate the detailed anatomy of the orbicularis oris muscle in the intact normal lip. The findings are correlated with clinical observations on lip function and modifications of technique are suggested that might improve the results in cleft lip repair.