Echocardiography in intensive care--where we are heading?

Point of care obstetric ultrasound knowledge retention among mid-wives following a training program: a prospective cohort pilot study

BACKGROUND

Obstetric ultrasound has become a routine part of antenatal care in many parts of the world including low income settings. However, there is a shortage of radiologists and sonographers to perform routine obstetric scans in many areas especially in the rural settings of low income countries, despite having equipment available to do this. As a result, Point of care ultrasound (POCUS) has been suggested to bridge this gap by training other health workers such as midwives to perform basic obstetric ultrasound as part of their clinical care.

METHODS

It was a prospective cohort pilot study in which trained midwives in point of care obstetric ultrasound were followed up at 6 months post training to assess their knowledge retention. Eleven trained midwives were purposively selected and followed up for knowledge retention. These were trained for 6 weeks and were given a knowledge assessment immediately after training, then given an assessment at 6 months following training. Data was analyzed using SPSS. Wilcoxon signed rank test was used to compare assessments and perceived knowledge as well as Spearman correlation to test the relationship between the number of scans performed and exam assessments, knowledge and exam assessments, and number of scans and knowledge.

RESULTS

There were eleven midwives, all female with an average age of 42.3 years. The mean exam score (out of 50) was 44.2 at the end of the training and 42.9 at 6-months follow up. The midwives demonstrated higher perceived knowledge at the end of the training when compared to the 6-months follow up. However, this perceived higher knowledge was not statistically significant when correlated with the exam scores either at the end of the training or at the follow up of 6 months.

CONCLUSION

This pilot study has demonstrated that training midwives in point of care obstetric ultrasound can result into acceptable levels of knowledge retention that assist the midwives to apply this knowledge when making routine clinical decisions in relation to pregnant women.

Echocardiographic assessment and critical care management of peri-partum women with unexpected left ventricular failure

Introduction

Cardiac disease remains the largest single cause of maternal death. Whilst uncommon, left ventricular failure during pregnancy and delivery can be devastating to both mother and child. Echocardiography can play a significant role in rapidly establishing a diagnosis, guiding initial therapy and then monitoring response.

Clinical vignettes

The history, presentation and management of three cases of peri-partum left ventricular failure is examined: stress cardiomyopathy in a 34 year old with twins, left ventricular dysfunction secondary to pre-eclampsia in a 22 year old with a singleton pregnancy and a true peri-partum cardiomyopathy in a 42 year old with IVF twins. The defining risk factors, presenting characteristics and echocardiographical findings for each pathology are highlighted.

Conclusion

Echocardiography is playing an increasingly important role in the immediate assessment and management of left ventricular failure. This is especially true in the peri-partum woman, where establishing the correct therapy is both challenging and crucial due to the significant cardiovascular changes that occur around the time of delivery. To this end we believe that echocardiography should be rapidly available to guide the management of these patients by a multidisciplinary team made up of obstetricians, cardiologists, anaesthetists and intensive care physicians.

[Knowledge retention after focused cardiac ultrasound training: a prospective cohort pilot study]

BACKGROUND AND OBJECTIVES

Focused Cardiac Ultrasound (FoCUS) has proven instrumental in guiding anesthesiologists' clinical decision-making process. Training residents to perform and interpret FoCUS is both feasible and effective. However, the degree of knowledge retention after FoCUS training remains a subject of debate. We sought to provide a description of our 4-week FoCUS curriculum, and to assess the knowledge retention among anesthesia residents at 6 months after FoCUS rotation.

METHODS

A prospective analysis involving eleven senior anesthesia residents was carried out. At end of FoCUS Rotation (EOR) participants completed a questionnaire (evaluating the number of scans completed and residents' self-rated knowledge and comfort level with FoCUS), and a multiple-choice FoCUS exam comprised of written- and video-based questions. Six months later, participants completed a follow-up questionnaire and a similar exam. Self-rated knowledge and exam scores were compared at EOR and after 6 months. Spearman correlations were conducted to test the relationship between number of scans completed and exam scores, perceived knowledge and exam scores, and number of scans and perceived knowledge.

RESULTS

Mean exam scores (out of 50) were 44.1 at EOR and 43 at the 6-month follow-up. Residents had significantly higher perceived knowledge (out of 10) at EOR (8.0) than at the 6-month follow-up (5.5), p=0.003. At the EOR, all trainees felt comfortable using FoCUS, and at 6 months 10/11 still felt comfortable. All the trainees had used FoCUS in their clinical practice after EOR, and the most cited reason for not using FoCUS more frequently was the lack of perceived clinical need. A strong and statistically significant (rho=0.804, p=0.005) correlation between number of scans completed during the FoCUS rotation and 6-month follow-up perceived knowledge was observed.

CONCLUSION

Four weeks of intensive FoCUS training results in adequate knowledge acquisition and 6-month knowledge retention.

A training programme in screening echocardiography

BACKGROUND

  Although the value of echocardiography in acutely unwell patients is well established, it is often difficult to deliver conventional studies immediately. This has led to the development of training programmes in screening echocardiography.

CONTEXT

  Echocardiography is a difficult skill to master and requires an integration of knowledge-based learning and mentored practical training.

INNOVATION

  We developed a three-stage programme: (1) a 1-day course containing didactic lectures on normal and abnormal pathology, a 2-hour practical element with rotation through different tutors then seminars and self-assessment, with an interactive quiz; (2) a period of consolidation via apprenticeship with a recognised trainer; and (3) formal assessment.

IMPLICATIONS

  We propose a specific training programme to teach the difficult practical skill of screening echocardiography. The use of theoretical and practical elements with structured teaching and an apprenticeship may serve as a model for teaching other practical skills in clinical medicine.

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.

Trauma Resuscitation Using Echocardiography in a Deployed Military Intensive Care Unit

Casualties with severe traumatic injury frequently suffer haemodynamic instability. There is interest in the use of transthoracic echocardiography (TTE) to assess haemodynamic status in intensive care resuscitation. We describe a feasibility study of focused TTE (fTTE) echocardiography in trauma resuscitation in a deployed military setting. fTTE was performed on patients admitted to ICU following severe injury. Data were collected on TTE view availability, LV function, volume status, and inferior vena cava (IVC) dimensions. Doppler of the LV outflow tract was performed to provide a velocity time integer (LVOT VTi) as an indicator of preload. Twenty-three patients were recruited, and 48 individual studies performed. TTE windows available were: parasternal long axis-68%, parasternal short axis-66%, apical 4-chamber-64%, subcostal-66%. IVC imaging was possible in 85%, and LVOT VTi Doppler in 37%. The mean maximal IVC diameter in volume-optimised patients (Group 1, n=19) was 2.07 cm (±0.07), compared with 1.47 (±0.06) in the hypovolaemic cohort (Group 2, n=23). The mean minimum IVC diameter in Group 1 was 1.93(±0.07) vs 1.03(±0.08) in Group 2. IVC collapsibility was 3.16% (±1.61%) in Group 1 vs 30.81%(±1.62) in Group 2. In 12%, profound hypovolaemia with systolic LV cavity obliteration was noted. fTTE suggested hypovolaemia in 69% of patients on admission to the study. Of patients arriving on the ICU following damage-control resuscitation only 31% were volume-optimised. fTTE led to a change in volume management strategy in 47% of cases. This study demonstrates, for the first time in a deployed military setting, that intensivist-delivered fTTE is feasible and changes resuscitation strategy in almost half of patients admitted to a deployed ICU.