[Diagnostics and treatment of selected clinically relevant, acute drug intoxications]

Acute drug poisoning due to accidental or self-damaging overdoses is responsible for 5-10% of emergency medical interventions in Germany. The treatment of asymptomatic to life-threatening courses requires extensive expertise. On the basis of a selective literature search, this article gives an overview of selected clinically relevant, acute drug poisonings with regard to epidemiology, symptomatology, diagnostics, and therapy.Intoxications with psychotropic drugs are the most common drug intoxications. Poisoning with tricyclic antidepressants causes anticholinergic, central nervous, and cardiovascular symptoms. Less toxic are selective serotonin reuptake inhibitors (SSRIs); the intoxication may be characterized by serotonin syndrome. Malignant neuroleptic syndrome is a severe complication of neuroleptic poisoning.Poisoning with analgesics is clinically relevant due to its high availability. For paracetamol poisoning, intravenous acetylcysteine is available as an antidote. Hemodialysis may be indicated for severe salicylate intoxication. Poisoning with nonsteroidal anti-inflammatory drugs is usually only associated with mild signs of intoxication.Poisoning with cardiac drugs (β-blockers and calcium antagonists) can cause life-threatening cardiovascular events. In addition to symptomatic therapy, insulin glucose therapy also plays an important role.The majority of acute drug poisonings can be treated adequately by symptomatic and partly intensive care therapy - if necessary with the application of primary and secondary toxin elimination. Depending on the severity of the intoxication, pharmacology-specific therapy must be initiated.

Applicability of stroke volume variation in patients of a general intensive care unit: a longitudinal observational study

Sinus rhythm (SR) and controlled mechanical ventilation (CV) are mandatory for the applicability of respiratory changes of the arterial curve such as stroke volume variation (SVV) to predict fluid-responsiveness. Furthermore, several secondary limitations including tidal volumes <8 mL/kg and SVV-values within the "gray zone" of 9-13% impair prediction of fluid-responsiveness by SVV. Therefore, we investigated the prevalence of these four conditions in general ICU-patients. This longitudinal observational study analyzed a prospectively maintained haemodynamic database including 4801 transpulmonary thermodilution and pulse contour analysis measurements of 278 patients (APACHE-II 21.0 ± 7.4). The main underlying diseases were cirrhosis (32%), sepsis (28%), and ARDS (17%). The prevalence of SR and CV was only 19.4% (54/278) in the first measurements (primary endpoint), 18.8% (902/4801) in all measurements and 26.5% (9/34) in measurements with MAP < 65 mmHg and CI < 2.5 L/min/m² and vasopressor therapy. In 69.1% (192/278) of the first measurements and in 65.9% (3165/4801) of all measurements the patients had SR but did not have CV. In 1.8% (5/278) of the first measurements and in 2.5% (119/4801) of all measurements the patients had CV but lacked SR. In 9.7% (27/278) of the first measurements and in 12.8% (615/4801) of all measurements the patients did neither have SR nor CV. Only 20 of 278 (7.2%) of the first measurements and 8.2% of all measurements fulfilled both major criteria (CV, SR) and both minor criteria for the applicability of SVV. The applicability of SVV in ICU-patients is limited due to the absence of mandatory criteria during the majority of measurements.

A systematic database-derived approach to improve indexation of transpulmonary thermodilution-derived global end-diastolic volume

Global end-diastolic volume (GEDV) has been indexed to body surface area (BSA). However, data validating this indexation of GEDV are scarce. Furthermore, it has been suggested to index GEDV to "predicted BSA" based on predicted body weight. Therefore, we aimed to identify biometric parameters independently associated with GEDV. We analyzed a database including 3812 TPTD measurements in 234 patients treated in the ICU of a German university hospital. GEDVI indexed to actual BSA was significantly lower than GEDVI indexed to predicted BSA (748 ± 179 vs. 804 ± 190 mL/m²; p < 0.001). GEDV was independently associated with older age, male sex, height, and actual body weight. In a regression model for the estimation of GEDV, age and height were the most important parameters: Each year in age and each cm in height increased GEDV by 9 and 15 mL, respectively. In addition to height and weight also age and sex should be considered for indexation of GEDV.

Indexation of cardiac output to biometric parameters in critically ill patients: A systematic analysis of a transpulmonary thermodilution-derived database

PURPOSE

Cardiac output (CO) (liters per minute) is usually normalized (ie, indexed) to the patient's body surface area (BSA) resulting in the hemodynamic variable cardiac index (CI) (liters per minute per square meter). We aimed (1) to evaluate the impact of different body weight-based CO indexations on the resulting CI values and (2) to identify biometric parameters independently associated with CO in critically ill patients.

MATERIALS AND METHODS

The study is an analysis of a database containing transpulmonary thermodilution-derived hemodynamic variables of 234 medical intensive care unit patients.

RESULTS

Cardiac index indexed to actual BSA was statistically significantly lower compared with CI indexed to predicted BSA in the totality of patients and in the subgroups of patients with body mass index greater than or equal to 25 kg/m(2) but less than 30 kg/m(2) and body mass index greater than or equal to 30 kg/m(2) (with a statistically significant difference in the proportion of low and high CI measurements). Multivariate analysis of the first CO measurement of each patient demonstrated that CO was independently associated with age (P < .001), height (P = .001), and actual body weight (BWact) (P = .030). Multivariate analysis of the mean of the patients' CO measurements confirmed age (P < .001), height (P = .001), and BWact (P < .001) as biometric factors independently associated with CO. Age was identified as the most important factor with each year of age decreasing CO by 66 mL/min (95% confidence interval, 47-86 mL/min).

CONCLUSIONS

The indexation of CO to BSA is highly dependent on the body weight estimation formula used to calculate BSA. Cardiac output is independently associated with the biometric factors age, height, and BWact. These factors might be considered for indexation of CO.

Extravascular lung water and its association with weight, height, age, and gender: a study in intensive care unit patients

Purpose

With regard to large inter-individual variability of height, body weight (BW), and age, several hemodynamic parameters are adjusted for biometric data. This also applies to extravascular lung water (EVLW), which traditionally was indexed to actual BW (BW-act) resulting in EVLW-index (EVLWI; i.e., EVLWI-act). Since indexation to BW-act might inappropriately diminish EVLWI-act in obese patients, the indexation has been changed to predicted BW (BW-pred) resulting in EVLWI-pred. BW-pred is a weight estimation formula calculated from height and gender that has not been derived from population-based data. The aim of the study was to investigate the independent association of biometric data with EVLW.

Methods

We analyzed a hemodynamic monitoring database including 3,691 transpulmonary thermodilution-derived EVLW measurements (234 consecutive patients; intensive care unit of a university hospital). We performed univariate and multivariate analyses regarding the association of biometric data with the first EVLW measurement and the mean EVLW value of each patient.

Results

In univariate analysis, the first EVLW significantly correlated with height (r = 0.254; p < 0.001), but neither with age nor BW-act. Similar findings were made in the analysis of the patients’ EVLW means of all measurements (“one point per patient”). In multivariate analysis (primary endpoint), including BW-act, height, age, and gender, only height was independently associated with EVLW, with each centimeter of height increasing the first measurement of EVLW by 6.882 mL (p < 0.001) and mean EVLW by 6.727 mL (p < 0.001).

Conclusions

Height is the only biometric parameter independently associated with the first and mean EVLW. In adult patients, EVLW should be indexed to height.