Echocardiography for cardiopulmonary optimization in the intensive care unit: should we expand its use?

Prospective assessment of a score for assessing basic critical-care transthoracic echocardiography skills in ventilated critically ill patients

Background

We studied a score for assessing basic transthoracic echocardiography (TTE) skills exhibited by residents who examined critically ill patients receiving mechanical ventilation.

Methods

We conducted a prospective study in the 16 residents who worked in our medical-surgical ICU between 1 May 2008 and 1 November 2009. The residents received theoretical teaching (two hours) then performed supervised TTEs during their six-month rotation. Their basic TTE skills in mechanically ventilated patients were evaluated after one (M1), three (M3), and six (M6) months by two experts, who used a scoring system devised for the study. After scoring, residents gave their hemodynamic diagnosis and suggested a treatment.

Results

The 4 residents with previous TTE skills obtained a significantly higher total score than did the 12 novices at M1 (18 (16 to 19) versus 13 (10 to 15), respectively, P = 0.03). In the novices, the total score increased significantly during training (M1, 13 (10 to 14); M3, 15 (12 to 16); and M6, 17 (15 to 18); P < 0.001) and correlated significantly with the number of supervised TTEs (r = 0.68, P < 0.0001). In the overall population, agreement with experts regarding the diagnosis and treatment was associated with a significantly higher total score (17 (16 to 18) versus 13 (12 to 16), P = 0.002). A total score ≥ 19/20 points had 100% specificity (95% confidence interval, 79 to 100%) for full agreement with the experts regarding the diagnosis and treatment.

Conclusions

Our results validate the scoring system developed for our study of the assessment of basic critical-care TTE skills in residents.

Focused critical care echocardiography

OBJECTIVE

Portable ultrasound is now used routinely in many ICUs for various clinical applications. Echocardiography performed by noncardiologists, both transesophageal and transthoracic, has evolved to broad applications in diagnosis, monitoring, and management of critically ill patients. This review provides a current update on focused critical care echocardiography for the management of critically ill patients.

METHOD

Source data were obtained from a PubMed search of the medical literature, including the PubMed "related articles" search methodology.

SUMMARY AND CONCLUSIONS

Although studies demonstrating improved clinical outcomes for critically ill patients managed by focused critical care echocardiography are generally lacking, there is evidence to suggest that some intermediate outcomes are improved. Furthermore, noncardiologists can learn focused critical care echocardiography and adequately interpret the information obtained. Noncardiologists can also successfully incorporate focused critical care echocardiography into advanced cardiopulmonary life support. Formal training and proctoring are important for safe application of focused critical care echocardiography in clinical practice. Further outcomes-based research is urgently needed to evaluate the efficacy of focused critical care echocardiography.

Introduction of an Echocardiography Service to a General Intensive Care Unit

Studies have suggested that significant undiagnosed pathology exists in the intensive care unit (ICU) population, and that bedside transthoracic echocardiography (TTE) can aid prompt diagnosis with potential outcome benefits. This study assesses the introduction of a bedside echocardiography service on patient care in a tertiary university intensive care unit (ICU). Data were collected from 101 TTEs, of which 58 were full studies and 43 were screening TTEs with a limited dataset. Seventy-five scans (74%) revealed previously undiagnosed pathology, which was considered serious in 30 (30%) cases. The most commonly diagnosed pathologies were: severe ventricular dysfunction (n=19), severe valvular dysfunction (n=9) and severe pulmonary hypertension (n=4). Full studies were more likely than screening studies to reveal previously undiagnosed pathology (47/58 vs 28/43 studies, p=0.035). However, the number of patients whose management was changed as a result of TTE was not significantly different between the two groups. Overall, patient management was altered as a result of the TTE in 51 cases (50%), and 11 patients (11%) were subsequently referred for cardiology consultation. In keeping with previous work, we have found that TTE uncovered a high percentage of unsuspected cardiac abnormalities, which impacted management in half of the patients who were scanned.

Pleural effusion decreases left ventricular pre-load and causes haemodynamic compromise: an experimental porcine study

BACKGROUND

Although pleural effusion is a common complication in critically ill patients, detailed knowledge is missing about the haemodynamic impact and the underlining mechanisms. The aim of this study was to evaluate the haemodynamic effect of incremental pleural effusion by means of invasive haemodynamic parameters and transthoracic echocardiography.

METHODS

This experimental interventional study was conducted using 22 female piglets (17.5-21.5 kg) randomized for right-side (n = 9) and left-side (n = 9) pleural effusion, or sham operation (n = 4). Pleural effusion was induced by infusing incremental volumes of saline into the pleural cavity. Invasive haemodynamic measurements and echocardiographical images were obtained at baseline, a volume of 45 ml/kg, a volume of 75 ml/kg and 45 min after drainage.

RESULTS

No difference (all P > 0.147) was found between right- and left-side pleural effusion, and the groups were thus pooled. At 45 ml/kg cardiac output, mean arterial pressure, stroke volume and mixed venous saturation decreased (all P < 0.003); central venous pressure and pulmonary arterial pressure increased (both P > 0.003) at this point. The changes accelerated at 75 ml/kg. At 45 ml/kg left ventricular pre-load in terms of end-diastolic area decreased significantly (P < 0.001). The effect on haemodynamics and cardiac dimensions changed dramatically at 75 ml/kg. Cardiac output, mean arterial pressure, central venous pressure and left ventricular end-diastolic area returned to normal during a recovery period of 45 min (all P > 0.061).

CONCLUSION

Incremental volumes of unilateral pleural effusion induced a significant haemodynamic impact fully reversible after drainage. Pleural effusion causes a significant decrease of left ventricular pre-load in a diverse picture of haemodynamic compromise.

Impact of echocardiography on patient management in the intensive care unit: an audit of district general hospital practice

BACKGROUND

Echocardiography has been shown to positively impact on the management of the critically ill patient. However, many published studies have a significant bias towards inclusion of cardiothoracic patients. We present an audit of the impact of echocardiography on the management of patients in a district general hospital intensive care unit (ICU).

METHODS

We conducted a prospective audit of all echocardiograms, both transthoracic (TTE) and transoesophageal (TOE), performed on our ICU between October 1, 2005, and December 31, 2007. In addition to patient characteristics, we recorded the indication for the echocardiogram, and any change in management that occurred as a result of the study.

RESULTS

Two hundred and fifty-eight echocardiograms were performed in 217 patients, of which 224 (86.8%) were performed by intensive care consultants. One hundred and eighty-seven studies (72.4%) were TTEs and 71 (27.8%) were TOEs. TTE provided diagnostic images in 91.3% of spontaneously breathing and 84.2% of mechanically ventilated patients. Management was changed directly as a result of information provided in 51.2% of studies. Changes included fluid administration, inotrope or drug therapy, and treatment limitation.

CONCLUSIONS

Echocardiography may have a significant impact on the management of patients in the general ICU. We recommend that appropriate training in echocardiography should be incorporated into the intensive care curriculum in the UK.

Echocardiography practice, training and accreditation in the intensive care: document for the World Interactive Network Focused on Critical Ultrasound (WINFOCUS)

Echocardiography is increasingly used in the management of the critically ill patient as a non-invasive diagnostic and monitoring tool. Whilst in few countries specialized national training schemes for intensive care unit (ICU) echocardiography have been developed, specific guidelines for ICU physicians wishing to incorporate echocardiography into their clinical practice are lacking. Further, existing echocardiography accreditation does not reflect the requirements of the ICU practitioner. The WINFOCUS (World Interactive Network Focused On Critical UltraSound) ECHO-ICU Group drew up a document aimed at providing guidance to individual physicians, trainers and the relevant societies of the requirements for the development of skills in echocardiography in the ICU setting. The document is based on recommendations published by the Royal College of Radiologists, British Society of Echocardiography, European Association of Echocardiography and American Society of Echocardiography, together with international input from established practitioners of ICU echocardiography. The recommendations contained in this document are concerned with theoretical basis of ultrasonography, the practical aspects of building an ICU-based echocardiography service as well as the key components of standard adult TTE and TEE studies to be performed on the ICU. Specific issues regarding echocardiography in different ICU clinical scenarios are then described. Obtaining competence in ICU echocardiography may be achieved in different ways - either through completion of an appropriate fellowship/training scheme, or, where not available, via a staged approach designed to train the practitioner to a level at which they can achieve accreditation. Here, peri-resuscitation focused echocardiography represents the entry level--obtainable through established courses followed by mentored practice. Next, a competence-based modular training programme is proposed: theoretical elements delivered through blended-learning and practical elements acquired in parallel through proctored practice. These all linked with existing national/international echocardiography courses. When completed, it is anticipated that the practitioner will have performed the prerequisite number of studies, and achieved the competency to undertake accreditation (leading to Level 2 competence) via a recognized National or European examination and provide the appropriate required evidence of competency (logbook). Thus, even where appropriate fellowships are not available, with support from the relevant echocardiography bodies, training and subsequently accreditation in ICU echocardiography becomes achievable within the existing framework of current critical care and cardiological practice, and is adaptable to each countrie's needs.

Toward an ultrasound curriculum for critical care medicine

Accurate assessment and rapid decision-making are essential to save lives and improve performance in critical care medicine. Real-time point-of-care ultrasound has become an invaluable adjunct to the clinical evaluation of critically ill and injured patients both for pre- and in-hospital situations. However, a high level of quality is necessary, guaranteed by appropriate education, experience, credentialing, quality control, continuing education, and professional development. Although educational recommendations have been proposed by a variety of nonimaging specialties, to date they are still scattered and limited examples of standards for critical and intensive care professionals. The challenge of providing adequate specialty-specific training, as encouraged by major medical societies, is made even more difficult by the diversity of critical care ultrasound utilization by various subspecialties in a variety of settings and numerous countries. In order to meet this educational challenge, a standard core curriculum is presented in this manuscript. The proposed curriculum is built on a competence, performance, and outcomes-based approach that is tailored to setting-specific training needs and prioritized according to critical problem-based pathways, rather than traditional organ-based systems. A multiple goal-oriented style fully addresses the specialty-specific approach of critical and intensive care professionals, who typically deal with disease states in complex scenarios rather than individual organ complaints. Because of the variation in the concept of what constitutes critical care worldwide, and the rate of change of information and technology, this manuscript attempts to present a learning system addressing a variety of needs for a rapidly changing world.