Early tracheostomy decreases ventilation time but has no impact on mortality of intensive care patients: a randomized study.

BACKGROUND: Long-term ventilation in intensive care units (ICUs) is associated with several problems such as increased mortality, increased rates of ventilator-associated pneumonia (VAP), and prolonged time of hospitalization, and thus leads to enormous healthcare expenditure. While the influence of tracheostomy on VAP incidence, duration of ventilation, and time of hospitalization has already been analyzed in several studies, the timing of the tracheostomy procedure on patient's mortality is still controversial. The aim of our study was to investigate whether early tracheostomy improved outcome in critically ill patients. MATERIALS AND METHODS: Within 2 years, 100 critically ill, predominantly surgical patients entered this prospective randomized study. A percutaneous dilatational tracheostomy was performed either early (≤4 days, 2.8 days median) or late (≥6 days, 8.1 days median) after intubation. RESULTS: We could demonstrate that mortality was not significantly reduced in the early tracheostomy (ET) group in contrast to the late tracheostomy (LT) group. ET was associated with decreased VAP incidence (ET 38% vs. LT 64%), decreased duration of ventilation (ET 367.5 h vs LT 507.5 h), and shorter time of hospitalization both in hospital (ET 31.5 days vs LT 68 days) and in ICU (ET 21.5 days vs LT 27 days). CONCLUSION: Despite many advantages like reduced time of ventilation and hospitalization, early tracheostomy is not associated with decreased mortality in critically ill patients.

Small cause - big effect: improvement in interface design results in improved data quality - a multicenter crossover study.

In Germany the core data set for anesthesia version 3.0 was recently introduced for external quality assurance, which includes five surgical tracer procedures. We found a low rate of correctly documented tracers when compared to procedure data (OPS-Codes) documented separately. Examination revealed that the graphical user interface (GUI) contravened the dialogue principles as defined in EN ISO 9241-110. We worked with the manufacturer to implement small improvements and roll out the software. A crossover study was conducted at a university hospital and a municipal hospital chain with five hospitals. All study sites and surgical tracer procedures combined, we found an improvement from 42% to 65% (p<0.001; N=34,610) correctly documented anesthesias. We also saw improvements for most of the observed surgical tracer procedures at all hospitals. Our results show the big effect small changes to the GUI can have on data quality. They also raise the question, if highly flexible and parameterized clinical documentation systems are suited to achieve high usability. Finding the right balance between GUIs designed by usability experts and the flexibility of parameterization by administrators will be a difficult task for the future and subject to further research.

The impact of long-lasting preemptive epidural analgesia before total hip replacement on the hormonal stress response. A prospective, randomized, double-blind study.

UNLABELLED: Recent studies suggest that preemptive analgesia may be effective in reducing postoperative pain. One physiologic explanation may be interference with the endogenous opioid response. We investigated whether long-lasting preoperative preemptive analgesia may have an effect on the hormonal stress response after total hip replacement. METHODS: 42 patients scheduled for elective hip replacement for coxarthrosis were randomized to receive, on the day before the operation, either 5 ml*h(-1) ropivacaine 0.2% (study group, n = 21) or 5 ml*h(-1) saline (control group, n = 21). Postoperative analgesia was achieved in both groups by patient-controlled epidural analgesia (PCEA) with ropivacaine 0.2%. The main outcome measure was the concentration of authentic beta-endorphin [1-31] in plasma up to 4 days after surgery. Additional parameters included concentrations of adrenocorticotrope hormone and cortisol. RESULTS: Both groups were comparable concerning preoperative parameters and pain scores. Epidural blocks were sufficient in all patients for operative analgesia. Preemptive analgesia was performed for 11-20 hours in both groups and led to significantly decreased pain scores before surgery. Preemptive analgesia with epidural ropivacaine did not lead to decreased concentrations of beta-endorphin [1-31] before the start of surgery or in the postoperative period. Furthermore, no differences could be detected in the time course of beta-endorphin and adrenocorticotrope hormone after surgery. However, cortisol concentrations differed significantly between groups before the operation, but showed a comparable rise after surgery. CONCLUSION: Differences in postoperative pain after preemptive analgesia do not seem to be due to an altered endogenous opioid response.

Increased body mass index and peri-operative risk in patients undergoing non-cardiac surgery.

BACKGROUND: Increased BMI is a well known risk factor for morbidity and mortality in hospitalized nonsurgical patients. However, the published evidence for a comparable effect in surgical patients is scarce. METHODS: This retrospective study was designed to assess the attributable effects of increased BMI (>30 kg/m2) on outcome (hospital mortality, admission to the intensive care unit (ICU), and incidence of intraoperative cardiovascular events (CVE)) in patients undergoing non-cardiac surgery by a computerized anesthesia record-keeping system. The study is based on data-sets of 28065 patients. Cases were defined as patients with BMI >30; controls (BMI 20-25) were automatically selected according to matching variables (ASA physical status, high risk and urgency of surgery, age and sex) in a stepwise fashion. Differences in outcome measures were assessed using univariate analysis. Stepwise regression models were developed to predict the impact of increased BMI on the different outcome measures. RESULTS: 4726 patients (16.8%) were found with BMI >30. Matching was successful for 41.5% of the cases, leading to 1962 cases and controls. The crude mortality rates were 1.1% (cases) vs 1.2% (controls); P =0.50, power=0.88). Admission to ICU was deemed necessary in 6.8% (cases) vs 7.5% (controls), P =0.42, power=0.65, and CVE were detected from the database in 22.3% (cases) vs 21.6% (controls), P =0.30, power=0.60. Using logistic regression analyses, no significant association between higher BMI and outcome measures could be verified. CONCLUSION: Increased BMI alone was not a factor leading to an increased perioperative risk in non-cardiac surgery. This fact may be due to an elevated level of attention while caring for obese patients.

Excessive alcohol consumption and perioperative outcome.

BACKGROUND: Excessive alcohol consumption is a well-recognized factor contributing to premature morbidity and mortality. METHODS: This retrospective, matched cohort study was designed to assess the attributable effects of excessive alcohol consumption on outcome in patients undergoing noncardiac surgery. All data of 28,065 patients operated at a tertiary care university hospital were recorded with a computerized anesthesia record-keeping system. Cases were defined as patients with history of excessive alcohol consumption (>30 g alcohol per day). Controls were selected according to matching variables in a stepwise fashion. RESULTS: In our data set, 928 patients (3.3%) were found with a history of excessive alcohol consumption. Matching was successful in 897 patients (97%). The crude mortality rates for the cases were 1.3% and 1.6%, for the matched controls (P=.084, power=0.85). Prolonged length of hospital stay was observed in 38% versus 33% (P=.013, power=0.50), admission to the intensive care unit was deemed necessary in 11% versus 9% (P=.027, power=0.55), and intraoperative cardiovascular events were detected from the database in 22% versus 21% (P=.053, power=0.61). CONCLUSIONS: In this study, history of excessive alcohol consumption alone is not a factor leading to an increased perioperative risk in noncardiac surgery.

Automatic calculation of the nine equivalents of nursing manpower use score (NEMS) using a patient data management system.

OBJECTIVE: The most recent approach to estimate nursing resources consumption has led to the generation of the Nine Equivalents of Nursing Manpower use Score (NEMS). The objective of this prospective study was to establish a completely automatically generated calculation of the NEMS using a patient data management system (PDMS) database and to validate this approach by comparing the results with those of the conventional manual method. DESIGN: Prospective study. SETTING: Operative intensive care unit of a university hospital. PATIENTS: Patients admitted to the ICU between 24 July 2002 and 22 August 2002. Patients under the age of 16 years, and patients undergoing cardiovascular surgery or with burn injuries were excluded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The NEMS of all patients was calculated automatically with a PDMS and manually by a physician in parallel. The results of the two methods were compared using the Bland and Altman approach, the interclass correlation coefficient (ICC), and the kappa-statistic. On 20 consecutive working days, the NEMS was calculated in 204 cases. The Bland Altman analysis did not show significant differences in NEMS scoring between the two methods. The ICC (95% confidence intervals) 0.87 (0.84-0.90) revealed a high inter-rater agreement between the PDMS and the physician. The kappa-statistic showed good results (kappa>0.55) for all NEMS items apart from the item "supplementary ventilatory care". CONCLUSION: This study demonstrates that automatical calculation of the NEMS is possible with high accuracy by means of a PDMS. This may lead to a decrease in consumption of nursing resources.

Review of antibiotic drug use in a surgical ICU: management with a patient data management system for additional outcome analysis in patients staying more than 24 hours.

BACKGROUND: A number of developments have been made in computerized patient data management systems (PDMSs), making them of interest to medical and nursing staff as a means of improving patient care. OBJECTIVES: The aim of this study was to assess the capability of a PDMS to record and provide drug-administration data and to investigate whether the PDMS may be used as a means of support for clinical audits and quality control. Furthermore, we assessed whether antibiotic therapy as a surrogate for infections correlates with hospital mortality in patients staying >24 hours in a surgical intensive care unit (SICU). METHODS: Because of its medical and economic importance in ICU treatment, we chose to use the field of antibiotic therapy as an example. A PDMS was used in a 14-bed SICU (Department of Anesthesiology, Intensive Care Medicine, and Pain Therapy, University Hospital Giessen, Giessen, Germany) to record relevant patient data, including therapeutic, diagnostic, and nursing actions. During a 15-month period (April 1, 2000 to June 30, 2001), antibiotic drug therapy was electronically analyzed and presented using the anatomic therapeutic chemical (ATC) category for antibacterials (ATC group, J01) with daily defined doses. Furthermore, the correlation of antibiotic therapy with patient outcome (hospital mortality) was tested using logistic regression analysis. RESULTS: A total of 2053 patients were treated in the SICU. Of these, 58.0% (1190 patients) received antibiotics (4479 treatment days; 13,145 single doses). Cephalosporins (ATC category, J01DA) were used most frequently (1785 treatment days [39.9% of treatment days]), followed by combinations of penicillins with beta-lactam inhibitors (ATC category, J01CR; 1478 treatment days [33.0%]) and imidazole derivatives (ATC category, J01XD; 667 treatment days [14.9%]). The antibiotic therapy lasted <3 days in 65.6% of cases. In 13.8% of cases, the treatment lasted >1 week. A total of 36.7% of cases were treated with only 1 antibiotic agent, 14.1% were given a combination of 2, and 7.2% were given a combination of > or =3 antibiotic agents. Seven hundred twenty-six patients remained in the SICU for >24 hours; 143 (19.7%) died during their hospital stay; 110 (15.2%) in the SICU. The duration of antibiotic therapy (odds ratio [OR], 1.46) and number of different antibiotic drugs used (OR, 2.15) significantly correlated with hospital mortality. CONCLUSIONS: Antibiotic therapy in a SICU can be assessed and analyzed in detail using a PDMS. Furthermore, in this study, the duration of antibiotic therapy and the number of antibiotic agents used correlated with hospital mortality. In further developing PDMSs, it is important for quality-assurance purposes to document the reasons for giving antibiotics and for changing prescriptions. It would also be helpful to integrate certain therapy standards and reminder functions for the duration of therapy in the PDMS.

Transesophageal echocardiography as a guide for patient positioning before neurosurgical procedures in semi-sitting position.

With an incidence of a patent foramen ovale in nearly one fourth of the normal population, neurosurgical procedures in the semi-sitting position are associated with the risk of paradoxical air embolism. The present study was undertaken to evaluate an anesthetic concept to detect a patent foramen ovale with the help of transesophageal echocardiography in anesthetized patients before neurosurgical procedures in the semi-sitting position. Transesophageal echocardiography was performed after induction of anesthesia before surgery to avoid additional physical and psychologic stress for the patients. Thirty-five neurosurgical patients scheduled for elective surgery in the semi-sitting position were examined with help of contrast transesophageal echocardiography. The data of the examined patients were analyzed with respect to efficiency, logistic efforts, and adverse events. Contrast transesophageal echocardiography was combined with a ventilation maneuver to increase right atrial pressure. A patent foramen ovale was detected in 3 of 35 patients. These patients were operated on in a supine position. Oral insertion of the echoprobe was possible in all patients without difficulties. A short-lasting hypertension was observed in 5 patients despite adequate analgesia and sedation. The average time of examination was 25 minutes. None of the patients showed paradoxical air embolism as judged by postoperative neurologic assessment. Contrast transesophageal echocardiography combined with a ventilation maneuver is an effective method in detecting a patent foramen ovale. Moreover, transesophageal echocardiography is a clinical guide to patient positioning. The method of anesthetic management presented to examine anesthetized patients immediately before surgery means less physical and psychologic stress for the patients and causes approximately a 30-minute delay of surgery.

Corrected incidences of co-morbidities - a statistical approach for risk-assessment in anesthesia using an AIMS.

OBJECTIVE: In anesthesia and intensive care logistic regression analysis are often used to generate predictive models for risk assessment. Strictly seen only independent variables should be represented in such prognostic models. Using anesthesia-information-management-systems a lot of (depending) information is stored in a database during the preoperative ward round. The objective of this study was to evaluate a statistical algorithm to process the different dependent variables without losing the information of each variable on patient's conditions. METHOD: Based on data about prognostic models in anesthesia an iterative statistical algorithm was initiated to summarize dependent variables to subscores. Seven subscores out of several preoperative variables were calculated corresponding to the proper incidence and the correlation to the occurrence of intraoperative cardiovascular events was evaluated. After that first step logistic regression was used to build a predictive model out of the seven subscores, 10 patient-related, and two surgery-related variables. Performance of the prognostic model was assessed using analysis of discrimination and calibration. RESULT: Four out of seven subscores together with age, type and urgency of surgery are represented in the prognostic model to predict the occurrence of intraoperative cardiovascular events. The prognostic model demonstrated good discriminative power with an area under the ROC curve (AUC) of 0.734. CONCLUSION: Due to reduced calibration, the clinical use of the prediction model is limited.

The incidence and risk factors for hypotension after spinal anesthesia induction: an analysis with automated data collection.

UNLABELLED: We sought to identify factors that are associated with hypotension after the induction of spinal anesthesia (SpA) by using an anesthesia information management system. Hypotension was defined as a decrease of mean arterial blood pressure of more than 30% within a 10-min interval, and relevance was defined as a therapeutic intervention with fluids or pressors within 20 min. From January 1, 1997, to August 5, 2000, data sets from 3315 patients receiving SpA were recorded on-line by using the automatic anesthesia record keeping system NarkoData. Hypotension meeting the predefined criteria occurred in 166 (5.4%) patients. Twenty-nine patient-, surgery-, and anesthesia-related variables were studied by using univariate analysis for a possible association with the occurrence of hypotension after SpA. Logistic regression with a forward stepwise algorithm was performed to identify independent variables (P < 0.05). The discriminative power of the logistic regression model was checked with a receiver operating characteristic curve. Calibration was tested with the Hosmer-Lemeshow goodness-of-fit test. The univariate analysis identified the following variables to be associated with hypotension after SpA: age, weight, height, body mass index, amount of plain bupivacaine 0.5% used for SpA, amount of colloid infusion before puncture, chronic alcohol consumption, ASA physical status, history of hypertension, urgency of surgery, surgical department, sensory block height of anesthesia, and frequency of puncture. In the multivariate analysis, independent factors for relevant hypotension after SpA consisted of three patient-related variables ("chronic alcohol consumption," odds ratio [OR] = 3.05; "history of hypertension," OR = 2.21; and the metric variable "body mass index," OR = 1.08) and two anesthesia-related variables ("sensory block height," OR = 2.32; and "urgency of surgery," OR = 2.84). The area of 0.68 (95% confidence interval, 0.63-0.72) below the receiver operating characteristic curve was significantly greater than 0.5 (P < 0.01). The goodness-of-fit test showed a good calibration of the model (H = 4.3, df = 7, P = 0.7; C = 7.3, df = 8, P = 0.51). This study contributes to the identification of patients with a high risk for hypotension after SpA induction, with the risk increasing two- or threefold with each additional risk factor. IMPLICATIONS: By using automated data collection, 5 (chronic alcohol consumption, history of hypertension, body mass index, sensory block height, and urgency of surgery) of 29 variables could be detected as having an association with hypotension after spinal anesthesia induction. The knowledge of these risk factors should be useful in increasing vigilance in those patients most at risk for hypotension, in allowing a more timely therapeutic intervention, or even in suggesting the use of alternative methods of spinal anesthesia, such as titrated continuous or small-dose spinal anesthesia.

Differing incidences of relevant hypotension with combined spinal-epidural anesthesia and spinal anesthesia.

UNLABELLED: In this investigation we assessed whether patients receiving spinal anesthesia (SPA) as part of combined spinal-epidural anesthesia (CSE) more often experience relevant hypotension than patients receiving SPA alone. From January 1, 1997, until August 5, 2000, electronic anesthesia records from 1596 patients having received SPA and 1023 patients having received CSE for elective surgery were collected by using a computerized anesthesia record-keeping system. Relevant hypotension was defined as a decrease of mean arterial blood pressure of more than 30% within a 10-min interval and a therapeutic action of the attending anesthesiologist within 20 min after onset. Electronic patient charts were reviewed by using logistic regression with a forward stepwise algorithm to identify independent risk factors that were associated with an increased incidence of hypotension after CSE. Univariate analysis was performed to assess differences in biometric data and relevant risk factors for hypotension between the two procedures. The incidence of relevant hypotension was more frequent with CSE than with SPA alone (10.9% versus 5.0%; P < 0.001). In the multivariate analysis, arterial hypertension (odds ratio, 1.83; 95% confidence interval, 1.21-2.78) and sensory block height >T6 (odds ratio, 2.81; 95% confidence interval, 1.88-4.22) were found to be factors associated with hypotension in the CSE group. Compared with patients receiving SPA alone, patients undergoing CSE had a significantly more frequent prevalence of arterial hypertension and higher sensory block levels (P < 0.01) despite smaller amounts of local anesthetics. In this study, patients receiving CSE had an increased risk for relevant hypotension as compared with patients with SPA alone. Part of this effect seems to be due to the procedure alone and not only because this population is at higher risk. IMPLICATIONS: This study, based on a large number of patients with a retrospective design by using on-line recorded data, suggests that spinal anesthesia as part of combined spinal-epidural anesthesia may more often lead to relevant hypotension than spinal anesthesia alone. Preexisting arterial hypertension and a sensory block height exceeding T6 are major risk factors for the development of this complication.

The incidence and prediction of automatically detected intraoperative cardiovascular events in noncardiac surgery.

UNLABELLED: The objective of this study was to evaluate prognostic models for quality assurance purposes in predicting automatically detected intraoperative cardiovascular events (CVE) in 58458 patients undergoing noncardiac surgery. To this end, we assessed the performance of two established models for risk assessment in anesthesia, the Revised Cardiac Risk Index (RCRI) and the ASA physical status classification. We then developed two new models. CVEs were detected from the database of an electronic anesthesia record-keeping system. Logistic regression was used to build a complex and a simple predictive model. Performance of the prognostic models was assessed using analysis of discrimination and calibration. In 5249 patients (17.8%) of the evaluation (n = 29437) and 5031 patients (17.3%) of the validation cohorts (n = 29021), a minimum of one CVE was detected. CVEs were associated with significantly more frequent hospital mortality (2.1% versus 1.0%; P < 0.01). The new models demonstrated good discriminative power, with an area under the receiver operating characteristic curve (AUC) of 0.709 and 0.707 respectively. Discrimination of the ASA classification (AUC 0.647) and the RCRI (AUC 0.620) were less. Neither the two new models nor ASA classification nor the RCRI showed acceptable calibration. ASA classification and the RCRI alone both proved unsuitable for the prediction of intraoperative CVEs. IMPLICATIONS: The objective of this study was to evaluate prognostic models for quality assurance purposes to predict the occurrence of automatically detected intraoperative cardiovascular events in 58,458 patients undergoing noncardiac surgery. Two newly developed models showed good discrimination but, because of reduced calibration, their clinical use is limited. The ASA physical status classification and the Revised Cardiac Risk Index are unsuitable for the prediction of intraoperative cardiovascular events.

Intra-operative tachycardia and peri-operative outcome.

BACKGROUND: Intra-operative tachycardia is a common adverse event, often recorded as an indicator for process quality in quality assurance projects in anaesthesia. METHODS: This retrospective study is based on data sets of 28,065 patients recorded with a computerised anaesthesia record-keeping system from 23 February 1999 to 31 December 2000 at a tertiary care university hospital. Cases were defined as patients with intra-operative tachycardia; references were automatically selected according to matching variables (high-risk surgery, severe congestive heart failure, severe coronary artery disease, significant carotid artery stenosis and/or history of stroke, renal failure, diabetes mellitus and urgency of surgery) in a stepwise fashion. Main outcome measures were hospital mortality, admission to the intensive care unit (ICU) and prolonged hospital stay. Differences in outcome measures between the matched pairs were assessed by univariate analysis. Stepwise regression models were developed to predict the impact of intra-operative tachycardia on the different outcome measures. RESULTS: In our study 474 patients (1.7%) were found to have had intra-operative tachycardia. Matching was successful for 99.4% of the cases, leading to 471 cases and references. The crude mortality rates for the cases and matched references were 5.5% and 2.5%, respectively (P=0.020). Of all case patients, 22.3% were treated in an ICU, compared to 11.0% of the matched references (P=0.001). Hospital stay was prolonged in 25.1% of the patients with tachycardia compared to 15.1% of the matched references (P=0.001). CONCLUSIONS: In this study, patients with intra-operative tachycardia who were undergoing non-cardiac surgery had a greater peri-operative risk, leading to increased mortality, greater frequency of admission to an ICU and prolonged hospital stay.