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.

Fatal cardiac tamponade as a result of a peripherally inserted central venous catheter: a case report and review of the literature.

We present a case of fatal cardiac tamponade that occurred in association with a peripherally inserted central catheter (PICC) inserted from the right antecubital fossa. Migration of the catheter from the right atrium within 24 h of insertion lead to the administration of a potassium-enriched sodium chloride solution into the pericardial space with the development of ST-segment elevation and progression to pulseless electrical activity and, subsequently, ventricular fibrillation. Although signs of tamponade were seen on echocardiography, we propose that myocardial hyperkalaemia from the diffusion of potassium through the epicardium accounted for some of the clinical picture. PICC lines carry a greater risk of migration because of the tip movement associated with arm abduction and, therefore, care must be taken to ensure that the catheter tip is correctly positioned to reduce this risk. When such catheters are used for intra-operative central venous access, we believe chest radiography is mandatory before fluid administration through the catheter, but that this is unnecessary when the catheter is being used solely for central venous pressure monitoring. The use of softer catheters may reduce the risk of vessel perforation. Once tamponade is suspected, all drugs and infusions administered via the catheter should be reviewed, the catheter aspirated and echocardiography performed urgently. This may be facilitated by the greater availability of limited bedside echocardiography within critical care units and theatre complexes.

General anaesthesia using remifentanil for caesarean section in parturients with critical aortic stenosis: a series of four cases.

Although heart disease is now the joint leading cause of maternal mortality in the UK, critical aortic stenosis is rarely encountered in parturients. Caesarean section is advisable in these patients to minimise the haemodynamic stress of labour and delivery. The use of an opioid-based general anaesthetic technique also helps to maintain cardiovascular stability. During a two-year period, four women with critical aortic stenosis requiring caesarean section presented to our institution. In all women, a rapid sequence induction of anaesthesia was performed using etomidate 0.1 to 0.2 mg.kg(-1), suxamethonium 1.5 mg.kg(-1) and remifentanil 2 to 4 micrograms.kg(-1). Anaesthesia was then maintained with isoflurane, nitrous oxide and a remifentanil infusion at 0.05 to 0.15 micrograms.kg(-1)min(-1). There was good haemodynamic stability throughout, except for a short period in one patient who became hypotensive after a significant post-partum haemorrhage secondary to uterine atony. All parturients were successfully extubated at the end of surgery and made excellent postoperative recoveries. Neonates were born in good condition with Apgar scores of 10, 9, 6 and 5 at 1 min and 10, 10, 10 and 10 at 5 min. We suggest that remifentanil is an ideal agent for parturients with severe aortic stenosis requiring general anaesthesia for caesarean section. Remifentanil provides cardiovascular stability in conjunction with rapid emergence from anaesthesia in the parturient and minimal side effects in the neonate.

Measurement of cardiac output by transpulmonary arterial thermodilution using a long radial artery catheter. A comparison with intermittent pulmonary artery thermodilution.

Cardiac output can be measured accurately by transpulmonary arterial thermodilution using the PiCCO (Pulsion Medical Systems, Munich, Germany) system with a femoral artery catheter. We have investigated the accuracy of a new 50 cm 4 French gauge radial artery catheter and the ability to use the system with a shorter radial catheter. We studied 18 patients who had undergone coronary artery surgery and made three simultaneous measurements of cardiac output by arterial thermodilution and with a pulmonary artery catheter. The radial catheter was withdrawn in 5 cm increments and the measurements were repeated. We found close agreement between arterial thermodilution and pulmonary artery thermodilution with a mean (SD) bias of 0.38 (0.77) l x min(-1). Arterial thermodilution became unreliable once the catheter had been withdrawn by more than 5 cm. We conclude that cardiac output measurement with arterial thermodilution with a radial catheter is interchangeable with that derived from a pulmonary artery catheter, and that a centrally sited arterial catheter is required for accurate determination of cardiac output by transpulmonary arterial thermodilution.

The 'swoosh' test--an evaluation of a modified 'whoosh' test in children.

BACKGROUND: Caudal analgesia is widely used in paediatric anaesthetic practice. In adults, the 'whoosh' test has been recommended as a guide to successful needle insertion, but it has not been extensively studied in paediatric patients. We have investigated a modification of the 'whoosh' test, which we have christened the 'swoosh' test. It avoids the injection of air by performing auscultation during injection of the local anaesthetic solution. We have compared it with clinical judgement of correct placement. METHODS: We studied 113 children undergoing elective surgery. During insertion of the caudal block, a stethoscope was placed over the lower lumbar spine and the presence or absence of an audible 'swoosh' noted. The operator's clinical impression of successful insertion was also recorded. RESULTS: The overall success rate of caudal anaesthesia was 95.6%. Of the 108 patients with a successful block, 98 had a positive 'swoosh' test. There were no false positive results. Calculations show the 'swoosh' test to have a sensitivity of 91%, a specificity of 100% and a positive predictive value of 100%. CONCLUSIONS: The 'swoosh' test is a simple and accurate test to confirm successful caudal insertion in children, and is especially useful as a teaching aid for anaesthetists new to the technique.