Objective
To describe current use and diagnostic and therapeutic impacts of point-of-care ultrasound (POCUS) in the intensive care unit (ICU).
Background
POCUS is of growing importance in the ICU. ...Several guidelines recommend its use for procedural guidance and diagnostic assessment. Nevertheless, its current use and clinical impact remain unknown.
Methods
Prospective multicentric study in 142 ICUs in France, Belgium, and Switzerland. All the POCUS procedures performed during a 24-h period were prospectively analyzed. Data regarding patient condition and the POCUS procedures were collected. Factors associated with diagnostic and therapeutic impacts were identified.
Results
Among 1954 patients hospitalized during the study period, 1073 (55 %) POCUS/day were performed in 709 (36 %) patients. POCUS served for diagnostic assessment in 932 (87 %) cases and procedural guidance in 141 (13 %) cases. Transthoracic echocardiography, lung ultrasound, and transcranial Doppler accounted for 51, 17, and 16 % of procedures, respectively. Diagnostic and therapeutic impacts of diagnostic POCUS examinations were 84 and 69 %, respectively. Ultrasound guidance was used in 54 and 15 % of cases for central venous line and arterial catheter placement, respectively. Hemodynamic instability, emergency conditions, transthoracic echocardiography, and ultrasounds performed by certified intensivists themselves were independent factors affecting diagnostic or therapeutic impacts.
Conclusions
With regard to guidelines, POCUS utilization for procedural guidance remains insufficient. In contrast, POCUS for diagnostic assessment is of extensive use. Its impact on both diagnosis and treatment of ICU patients seems critical. This study identified factors associated with an improved clinical value of POCUS.
Abstract Background Somatostatin may prevent the small-for-size syndrome in subjects undergoing extended hepatectomy by decreasing portal pressure. Methods Twenty pigs underwent 70% hepatectomy (H70 ...group, n = 7), 90% hepatectomy (H90 group, n = 7), or sham laparotomy (control group, n = 6). Splanchnic hemodynamics was measured before and after an intraoperative infusion of somatostatin. Results The portal vein flow normalized to liver weight increased in both H70 and H90 groups (from 125 ± 42 to 342 ± 82 mL/min/100g, P = .031 and from 140 ± 46 to 530 ± 241, P = .016, respectively). The hepatic venous pressure gradient (HVPG) increased in the H90 group only (from 5.5 ± 5.8 to 13 ± 4.9 mm Hg, P = .004). Somatostatin decreased portal vein flow normalized to liver weight in both H70 and H90 groups (from 408 ± 224 to 360 ± 227 mL/min/100g, P = .031 and from 560 ± 190 to 466 ± 189 mL/min/100g, P = .016), and restored a normal HVPG in the H90 group (from 14.3 ± 4.8 to 7.7 ± 6.1 mm Hg, P = .047). Conclusions Somatostatin restores a normal HVPG in the setting of small-for-size syndrome and can be considered as an effective pharmaceutical modality of portal inflow modulation after extended hepatectomy.
To evaluate the effect of increased intra-abdominal pressure (IAP) on the systolic and pulse pressure variations induced by positive pressure ventilation in a porcine model.
Experimental study in a ...research laboratory.
Seven mechanically ventilated and instrumented pigs prone to normovolaemia and hypovolaemia by blood withdrawal.
Abdominal banding gradually increased IAP in 5-mmHg steps up to 30 mmHg.
Variations in systolic pressure, pulse pressure, inferior vena cava flow, and pleural and transmural (LVEDPtm) left-ventricular end-diastolic pressure were recorded at each step. Systolic pressure variations were 6.1+/-3.1%, 8.5+/-3.6% and 16.0+/-5.0% at 0, 10, and 30 mmHg IAP in normovolaemic animals (mean+/-SD; p<0.01 for IAP effect). They were 12.7+/-4.6%, 13.4+/-6.7%, and 23.4+/-6.3% in hypovolaemic animals (p<0.01 vs normovolaemic group) for the same IAP. Fluctuations of the inferior vena cava flow disappeared as the IAP increased. Breath cycle did not induce any variations of LVEDPtm for 0 and 30 mmHg IAP.
In this model, the systolic pressure and pulse pressure variations, and inferior vena cava flow fluctuations were dependent on IAP values which caused changes in pleural pressure swing, and this dependency was more marked during hypovolaemia. The present study suggests that dynamic indices are not exclusively related to volaemia in the presence of increased IAP. However, their fluid responsiveness predictive value could not be ascertained as no fluid challenge was performed.
Contrast transthoracic echocardiography (TTE) is currently used to identify intrapulmonary shunt (IPS) in patients with end-stage liver disease. The aim of this study was to compare the use of ...contrast TTE and transesophageal echocardiography (TEE) in detecting IPS.
Thirty-seven consecutive outpatients with severe liver disease awaiting liver transplantation underwent contrast TEE and TTE. The IPS was assessed semiquantitatively in four grades with TEE and as positive or negative with TTE.
ICU.
Patients underwent contrast TEE after pharyngeal anesthesia alone followed by contrast TTE. Contrast echocardiography was performed with a modified fluid gelatin solution.
Overall detection rate of an IPS was 51% with TEE and 32% with TTE (p<0.001). Four patients had an IPS detected with TEE but not with TTE. Quality of imaging was poor in 22% with TTE and 0% with TEE (p<0.001). A PaO2 <80 mm Hg or a dyspnea was associated with an IPS in 56% and 50% of patients with TEE and in 33% and 25% with TTE, respectively.
Contrast-enhanced TEE is superior to TTE for detecting an IPS in patients with severe liver disease awaiting liver transplantation. The use of gelatin contrast solution allows an early detection of IPS. Because of the high sensitivity of TEE, all patients suspected of hepatopulmonary syndrome should undergo TEE in search of an IPS if TTE is normal.
The aim of this study was to evaluate dynamic indices of fluid responsiveness in a model of intra-abdominal hypertension.
Nine mechanically-ventilated pigs underwent increased intra-abdominal ...pressure (IAP) by abdominal banding up to 30 mmHg and then fluid loading (FL) at this IAP. The same protocol was carried out in the same animals made hypovolemic by blood withdrawal. In both volemic conditions, dynamic indices of preload dependence were measured at baseline IAP, at 30 mmHg of IAP, and after FL. Dynamic indices involved respiratory variations in stroke volume (SVV), pulse pressure (PPV), and systolic pressure (SPV, %SPV and Δdown). Stroke volume (SV) was measured using an ultrasound transit-time flow probe placed around the aortic root. Pigs were considered to be fluid responders if their SV increased by 15% or more with FL. Indices of fluid responsiveness were compared with a Mann-Whitney U test. Then, receiver operating characteristic (ROC) curves were generated for these parameters, allowing determination of the cut-off values by using Youden's method.
Five animals before blood withdrawal and all animals after blood withdrawal were fluid responders. Before FL, SVV (78 ± 19 vs 42 ± 17%), PPV (64 ± 18 vs 37 ± 15%), SPV (24 ± 5 vs 18 ± 3 mmHg), %SPV (24 ± 4 vs 17 ± 3%) and Δdown (13 ± 5 vs 6 ± 4 mmHg) were higher in responders than in non-responders (P < 0.05). Areas under ROC curves were 0.93 (95% confidence interval: 0.80 to 1.06), 0.89 (0.70 to 1.07), 0.90 (0.74 to 1.05), 0.92 (0.78 to 1.06), and 0.86 (0.67 to 1.06), respectively. Threshold values discriminating responders and non-responders were 67% for SVV and 41% for PPV.
In intra-abdominal hypertension, respiratory variations in stroke volume and arterial pressure remain indicative of fluid responsiveness, even if threshold values identifying responders and non-responders might be higher than during normal intra-abdominal pressure. Further studies are required in humans to determine these thresholds in intra-abdominal hypertension.
Liver failure is associated with hepatic and extrahepatic organ failure leading to a high short-term mortality rate. Extracorporeal albumin dialysis (ECAD) aims to reduce albumin-bound toxins ...accumulated during liver failure. ECAD detoxifies blood using albumin dialysis through an artificial semipermeable membrane with recirculation (molecular adsorbent recirculating system, MARS) or without (single-pass albumin dialysis, SPAD).
We performed a randomized crossover open trial in a surgical intensive care unit. The primary outcome of the study was total bilirubin reduction during MARS and during SPAD therapies. The secondary outcomes were conjugated bilirubin and bile acid level reduction during MARS and SPAD sessions and tolerance of dialysis system devices. Inclusion criteria were adult patients presenting liver failure with factor V activity <50% associated with bilirubin ≥250 μmol/L and a complication (either hepatic encephalopathy, severe pruritus, or hepatorenal syndrome). For MARS and SPAD, the dialysis flow rate was equal to 1,000 mL/h.
Twenty crossovers have been performed. Baseline biochemical characteristics (bilirubin, ammonia, bile acids, creatinine, and urea) were not statistically different between MARS and SPAD. Both ECAD have led to a significant reduction in total bilirubin (-83 ± 67 μmol/L after MARS; -122 ± 118 μmol/L after SPAD session), conjugated bilirubin (-82 ± 61 μmol/L after MARS; -105 ± 96 μmol/L after SPAD session), and bile acid levels (-64 ± 75 μmol/L after MARS; -56 ± 56 μmol/L after SPAD session), all nondifferent comparing MARS to SPAD.
A simple-to-perform SPAD therapy with equal to MARS dialysate flow parameters provides the same efficacy in bilirubin and bile acid removal. However, clinically relevant endpoints have to be evaluated in randomized trials to compare MARS and SPAD therapies and to define the place of SPAD in the liver failure care program.