Wider lessons of the pulmonary artery catheter trial

Pro-Con Debate: We should not Measure Cardiac output in Critical Care

The measurement of cardiac output in critical care appears to be increasingly common. However, both the monitoring technologies and the therapeutic approaches they inform have often proved highly controversial. As the range of alternative technologies available continues to increase, it seems worthwhile to question whether this monitoring modality should be used at all. The aim of this pro-con debate is to review the key evidence and to explain the often quite widely differing interpretations placed upon it. The term cardiac output monitoring refers to technology, whose primary purpose is to monitor global blood flow. The principles of the various technologies have been reviewed elsewhere.1

Designing clinical trials in acute lung injury/acute respiratory distress syndrome

PURPOSE OF REVIEW

To review the implications of recent literature for clinical trial design in acute lung injury/acute respiratory distress syndrome (ARDS).

RECENT FINDINGS

Refinement of acute lung injury/acute respiratory distress syndrome diagnostic criteria and study enrollment criteria, greater efforts to define usual care appropriately, and balancing of efficacy and effectiveness design principles will be key components of future trials.

SUMMARY

Clinical trial design in acute lung injury/acute respiratory distress syndrome faces many challenges. Although we have learned much from past trials, persistent design dilemmas must be addressed for future trials.

Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury

BACKGROUND

The balance between the benefits and the risks of pulmonary-artery catheters (PACs) has not been established.

METHODS

We evaluated the relationship of benefits and risks of PACs in 1000 patients with established acute lung injury in a randomized trial comparing hemodynamic management guided by a PAC with hemodynamic management guided by a central venous catheter (CVC) using an explicit management protocol. Mortality during the first 60 days before discharge home was the primary outcome.

RESULTS

The groups had similar baseline characteristics. The rates of death during the first 60 days before discharge home were similar in the PAC and CVC groups (27.4 percent and 26.3 percent, respectively; P=0.69; absolute difference, 1.1 percent; 95 percent confidence interval, -4.4 to 6.6 percent), as were the mean (+/-SE) numbers of both ventilator-free days (13.2+/-0.5 and 13.5+/-0.5; P=0.58) and days not spent in the intensive care unit (12.0+/-0.4 and 12.5+/-0.5; P=0.40) to day 28. PAC-guided therapy did not improve these measures for patients in shock at the time of enrollment. There were no significant differences between groups in lung or kidney function, rates of hypotension, ventilator settings, or use of dialysis or vasopressors. Approximately 90 percent of protocol instructions were followed in both groups, with a 1 percent rate of crossover from CVC- to PAC-guided therapy. Fluid balance was similar in the two groups, as was the proportion of instructions given for fluid and diuretics. Dobutamine use was uncommon. The PAC group had approximately twice as many catheter-related complications (predominantly arrhythmias).

CONCLUSIONS

PAC-guided therapy did not improve survival or organ function but was associated with more complications than CVC-guided therapy. These results, when considered with those of previous studies, suggest that the PAC should not be routinely used for the management of acute lung injury. (ClinicalTrials.gov number, NCT00281268.).

Health services research in critical care using administrative data

The aim of health services research is to provide unbiased, scientific evidence to influence health services policy at all levels. Secondary analysis of administrative data can be employed for the purpose of evaluating questions relevant to health services research in the field of critical care. This article provides an overview of the topic and specifically reviews the key components to evaluating and performing research in critical care using administrative data, including how to evaluate the quality of administrative data itself, and also how to evaluate the quality of studies that employ administrative data. The article concludes with a step-wise approach to conducting studies of critical care based on administrative data.

Recommended guidelines for reviewing, reporting, and conducting research on post-resuscitation care: The Utstein style

The aim of this report is to establish recommendations for reviewing, reporting, and conducting research during the post-resuscitation period in hospital. It defines data that are needed for research and more specialised registries and therefore supplements the recently updated Utstein template for resuscitation registries. The updated Utstein template and the out-of-hospital "Chain of Survival" describe factors of importance for successful resuscitation up until return of spontaneous circulation (ROSC). Several factors in the in-hospital phase after ROSC are also likely to affect the ultimate outcome of the patient. Large differences in survival to hospital discharge for patients admitted alive are reported between hospitals. Therapeutic hypothermia has been demonstrated to improve the outcome, and other factors such as blood glucose, haemodynamics, ventilatory support, etc., might also influence the result. No generally accepted, scientifically based protocol exists for the post-resuscitation period in hospital, other than general brain-oriented intensive care. There is little published information on this in-hospital phase. This statement is the result of a scientific consensus development process started as a symposium by a task force at the Utstein Abbey, Norway, in September 2003. Suggested data are defined as core and supplementary and include the following categories: pre-arrest co-morbidity and functional status, cause of death, patients' quality of life, in-hospital system factors, investigations and treatment, and physiological data at various time points during the first three days after admission. It is hoped that the publication of these recommendations will encourage research into the in-hospital post-resuscitation phase, which we propose should be included in the chain-of-survival as a fifth ring. Following these recommendations should enable better understanding of the impact of different in-hospital treatment strategies on outcome.

Knot in the Cava—An Unusual Complication of Swan–Ganz Catheters

Complications associated with the use of the Swan-Ganz catheters including coiling and knotting of the catheter in the central venous system or in the chambers of the heart, often with disastrous consequences. We report a case of knotting of a Swan-Ganz catheter in the superior vena cava which necessitated surgical removal via the right internal jugular vein.

The West Midlands "Severe Hypertensive Illness in Pregnancy" (SHIP) audit

OBJECTIVE

To study the management of a series of women presenting with acute-onset hypertension in the 21 maternity units in the West Midlands region, in order to measure the standard of care and the outcomes of these patients and their babies.

DESIGN

Multicenter audit.

SETTING

Twenty-one Maternity Units in the West Midlands region with 85,658 births during the audit period.

METHODS

Prospective data collection by named coordinators (multidisciplinary) in each unit using customized proformas. The proformas were then forwarded to the Research Coordinator for input onto a database and observational analyses.

RESULTS

The total number of cases was 516. Eighty-one percent were diagnosed as having severe preeclampsia, 14% HELLP syndrome, and 5% eclampsia. Seven percent were admitted to the intensive therapy unit. Seventy percent of births were preterm, 62% of babies were low birth weight (< 2.5 kg), 57% of babies were admitted to the neonatal unit, and the perinatal mortality rate was 5%. The commonest antihypertensive agents were hydralazine and nifedipine. In terms of compliance with audit standards, 61% had both oxygen saturation and noninvasive blood pressure monitoring, 47% had good fluid balance documentation, and 79% had no fluid mismanagement. Seventy-four percent were seen by a consultant obstetrician, 62% were seen by a member of an "expert team," 83% adhered to local guidelines, and 71% of eclamptics received magnesium sulfate (MgSO4).

CONCLUSION

Our study shows that severe hypertensive illness of pregnancy remains an important cause of maternal mortality and perinatal mortality. This audit highlights areas in which standards of care can be improved.