Angiotensin II treatment is associated with improved oxygenation in ARDS patients with refractory vasodilatory shock.

BACKGROUND: The physiological effects of renin-angiotensin system modulation in acute respiratory distress syndrome (ARDS) remain controversial and have not been investigated in randomized trials. We sought to determine whether angiotensin-II treatment is associated with improved oxygenation in shock-associated ARDS. METHODS: Post-hoc subgroup analysis of the Angiotensin Therapy for High Output Shock (ATHOS-3) trial. We studied patients who met modified Berlin ARDS criteria at enrollment. The primary outcome was PaO2/FiO2-ratio (P:F) at 48-h adjusted for baseline P:F. Secondary outcomes included oxygenation index, ventilatory ratio, PEEP, minute-ventilation, hemodynamic measures, patients alive and ventilator-free by day-7, and mortality. RESULTS: Of 81 ARDS patients, 34 (42%) and 47 (58%) were randomized to angiotensin-II or placebo, respectively. In angiotensin-II patients, mean P:F increased from 155 mmHg (SD: 69) at baseline to 265 mmHg (SD: 160) at hour-48 compared with no change with placebo (148 mmHg (SD: 63) at baseline versus 164 mmHg (SD: 74) at hour-48)(baseline-adjusted difference: + 98.4 mmHg [95%CI 35.2-161.5], p = 0.0028). Similarly, oxygenation index decreased by - 6.0 cmH2O/mmHg at hour-48 with angiotensin-II versus - 0.4 cmH2O/mmHg with placebo (baseline-adjusted difference: -4.8 cmH2O/mmHg, [95%CI - 8.6 to - 1.1], p = 0.0273). There was no difference in PEEP, minute ventilation, or ventilatory ratio. Twenty-two (64.7%) angiotensin-II patients had sustained hemodynamic response to treatment at hour-3 versus 17 (36.2%) placebo patients (absolute risk-difference: 28.5% [95%CI 6.5-47.0%], p = 0.0120). At day-7, 7/34 (20.6%) angiotensin-II patients were alive and ventilator-free versus 5/47(10.6%) placebo patients. Day-28 mortality was 55.9% in the angiotensin-II group versus 68.1% in the placebo group. CONCLUSIONS: In post-hoc analysis of the ATHOS-3 trial, angiotensin-II was associated with improved oxygenation versus placebo among patients with ARDS and catecholamine-refractory vasodilatory shock. These findings provide a physiologic rationale for trials of angiotensin-II as treatment for ARDS with vasodilatory shock. TRIAL REGISTRATION: ClinicalTrials.Gov Identifier: NCT02338843 (Registered January 14th 2015).

Initiating angiotensin II at lower vasopressor doses in vasodilatory shock: an exploratory post-hoc analysis of the ATHOS-3 clinical trial.

BACKGROUND: High dose vasopressors portend poor outcome in vasodilatory shock. We aimed to evaluate the impact of baseline vasopressor dose on outcomes in patients treated with angiotensin II (AT II). METHODS: Exploratory post-hoc analysis of the Angiotensin II for the Treatment of High-Output Shock (ATHOS-3) trial data. The ATHOS-3 trial randomized 321 patients with vasodilatory shock, who remained hypotensive (mean arterial pressure of 55-70 mmHg) despite receiving standard of care vasopressor support at a norepinephrine-equivalent dose (NED) > 0.2 µg/kg/min, to receive AT II or placebo, both in addition to standard of care vasopressors. Patients were grouped into low (≤ 0.25 µg/kg/min; n = 104) or high (> 0.25 µg/kg/min; n = 217) NED at the time of study drug initiation. The primary outcome was the difference in 28-day survival between the AT II and placebo subgroups in those with a baseline NED ≤ 0.25 µg/kg/min at the time of study drug initiation. RESULTS: Of 321 patients, the median baseline NED in the low-NED subgroup was similar in the AT II (n = 56) and placebo (n = 48) groups (median of each arm 0.21 µg/kg/min, p = 0.45). In the high-NED subgroup, the median baseline NEDs were also similar (0.47 µg/kg/min AT II group, n = 107 vs. 0.45 µg/kg/min placebo group, n = 110, p = 0.75). After adjusting for severity of illness, those randomized to AT II in the low-NED subgroup were half as likely to die at 28-days compared to placebo (HR 0.509; 95% CI 0.274-0.945, p = 0.03). No differences in 28-day survival between AT II and placebo groups were found in the high-NED subgroup (HR 0.933; 95% CI 0.644-1.350, p = 0.71). Serious adverse events were less frequent in the low-NED AT II subgroup compared to the placebo low-NED subgroup, though differences were not statistically significant, and were comparable in the high-NED subgroups. CONCLUSIONS: This exploratory post-hoc analysis of phase 3 clinical trial data suggests a potential benefit of AT II introduction at lower doses of other vasopressor agents. These data may inform design of a prospective trial. TRIAL REGISTRATION: The ATHOS-3 trial was registered in the clinicaltrials.gov repository (no. NCT02338843). Registered 14 January 2015.

Renin and Survival in Patients Given Angiotensin II for Catecholamine-Resistant Vasodilatory Shock. A Clinical Trial.

Rationale: Exogenous angiotensin II increases mean arterial pressure in patients with catecholamine-resistant vasodilatory shock (CRVS). We hypothesized that renin concentrations may identify patients most likely to benefit from such therapy.Objectives: To test the kinetic changes in renin concentrations and their prognostic value in patients with CRVS.Methods: We analyzed serum samples from patients enrolled in the ATHOS-3 (Angiotensin II for the Treatment of High-Output Shock) trial for renin, angiotensin I, and angiotensin II concentrations before the start of administration of angiotensin II or placebo and after 3 hours.Measurements and Main Results: Baseline serum renin concentration (normal range, 2.13-58.78 pg/ml) was above the upper limits of normal in 194 of 255 (76%) study patients with a median renin concentration of 172.7 pg/ml (interquartile range [IQR], 60.7 to 440.6 pg/ml), approximately threefold higher than the upper limit of normal. Renin concentrations correlated positively with angiotensin I/II ratios (r = 0.39; P < 0.001). At 3 hours after initiation of angiotensin II therapy, there was a 54.3% reduction (IQR, 37.9% to 66.5% reduction) in renin concentration compared with a 14.1% reduction (IQR, 37.6% reduction to 5.1% increase) with placebo (P < 0.0001). In patients with renin concentrations above the study population median, angiotensin II significantly reduced 28-day mortality to 28 of 55 (50.9%) patients compared with 51 of 73 patients (69.9%) treated with placebo (unstratified hazard ratio, 0.56; 95% confidence interval, 0.35 to 0.88; P = 0.012) (P = 0.048 for the interaction).Conclusions: The serum renin concentration is markedly elevated in CRVS and may identify patients for whom treatment with angiotensin II has a beneficial effect on clinical outcomes.Clinical trial registered with www.clinicaltrials.gov (NCT02338843).

Sensitivity to angiotensin II dose in patients with vasodilatory shock: a prespecified analysis of the ATHOS-3 trial.

BACKGROUND: Early clinical data showed that some patients with vasodilatory shock are responsive to low doses of angiotensin II. The objective of this analysis was to compare clinical outcomes in patients requiring ≤ 5 ng kg-1 min-1 angiotensin II at 30 min (≤ 5 ng kg-1 min-1 subgroup) to maintain mean arterial pressure (MAP) ≥ 75 mmHg versus patients receiving > 5 ng kg-1 min-1 angiotensin II at 30 min (> 5 ng kg-1 min-1 subgroup). Data from angiotensin II-treated patients enrolled in the ATHOS-3 trial were used. RESULTS: The subgroup of patients whose angiotensin II dose was down-titrated from 20 ng kg-1 min-1 at treatment initiation to ≤ 5 ng kg-1 min-1 at 30 min (79/163) had significantly lower endogenous serum angiotensin II levels and norepinephrine-equivalent doses and significantly higher MAP versus the > 5 ng kg-1 min-1 subgroup (84/163). Patients in the ≤ 5 ng kg-1 min-1 subgroup were more likely to have a MAP response at 3 h versus those in the > 5 ng kg-1 min-1 subgroup (90% vs. 51%, respectively; odds ratio, 8.46 [95% CI 3.63-19.7], P < 0.001). Day 28 survival was also higher in the ≤ 5 ng kg-1 min-1 subgroup versus the > 5 ng kg-1 min-1 subgroup (59% vs. 33%, respectively; hazard ratio, 0.48 [95% CI 0.28-0.72], P = 0.0007); multivariate analyses supported the survival benefit in patients with lower angiotensin II levels. The ≤ 5 ng kg-1 min-1 subgroup had a more favorable safety profile and lower treatment discontinuation rate than the > 5 ng kg-1 min-1 subgroup. CONCLUSIONS: This prespecified analysis showed that down-titration to ≤ 5 ng kg-1 min-1 angiotensin II at 30 min is an early predictor of favorable clinical outcomes which may be related to relative angiotensin II insufficiency.

Angiotensin II for the Treatment of Vasodilatory Shock.

BACKGROUND: Vasodilatory shock that does not respond to high-dose vasopressors is associated with high mortality. We investigated the effectiveness of angiotensin II for the treatment of patients with this condition. METHODS: We randomly assigned patients with vasodilatory shock who were receiving more than 0.2 µg of norepinephrine per kilogram of body weight per minute or the equivalent dose of another vasopressor to receive infusions of either angiotensin II or placebo. The primary end point was a response with respect to mean arterial pressure at hour 3 after the start of infusion, with response defined as an increase from baseline of at least 10 mm Hg or an increase to at least 75 mm Hg, without an increase in the dose of background vasopressors. RESULTS: A total of 344 patients were assigned to one of the two regimens; 321 received a study intervention (163 received angiotensin II, and 158 received placebo) and were included in the analysis. The primary end point was reached by more patients in the angiotensin II group (114 of 163 patients, 69.9%) than in the placebo group (37 of 158 patients, 23.4%) (odds ratio, 7.95; 95% confidence interval [CI], 4.76 to 13.3; P<0.001). At 48 hours, the mean improvement in the cardiovascular Sequential Organ Failure Assessment (SOFA) score (scores range from 0 to 4, with higher scores indicating more severe dysfunction) was greater in the angiotensin II group than in the placebo group (-1.75 vs. -1.28, P=0.01). Serious adverse events were reported in 60.7% of the patients in the angiotensin II group and in 67.1% in the placebo group. Death by day 28 occurred in 75 of 163 patients (46%) in the angiotensin II group and in 85 of 158 patients (54%) in the placebo group (hazard ratio, 0.78; 95% CI, 0.57 to 1.07; P=0.12). CONCLUSIONS: Angiotensin II effectively increased blood pressure in patients with vasodilatory shock that did not respond to high doses of conventional vasopressors. (Funded by La Jolla Pharmaceutical Company; ATHOS-3 ClinicalTrials.gov number, NCT02338843 .).

Teaching suturing in a workshop setting: a comparison of several models.

OBJECTIVES: Suturing is taught in workshops using a variety of models. The purpose of this study is to compare the resemblance to human skin of four models commonly used to teach suturing: pig skin, beef tongue, hot dog and latex glove. METHODS: 5 centimeter biconvex incisions were made in each of the models and closed by 50 physician study volunteers comprised of 33 board-certified physicians and 17 resident physicians. They rated each model on a scale of 1 to 4, where 4 closely resembles human skin and 1 does not resemble human skin. RESULTS: The following mean ratings were given by study volunteers: beef tongue 3.5 +/- 0.5, pig skin 3.2 +/- 0.8, latex glove 1.6 +/- 0.7, hot dog 1.4 +/- 0.6. CONCLUSION: Beef tongue and pig skin were rated highest by study volunteers. However, pig skin is much cheaper than beef tongue. Pig skin is the best inexpensive model for teaching skin suturing of the four models studied.

Problem based learning and medical malpractice: does how you've been trained make a difference?

Testing the hypothesis that physicians trained in problem based learning formats versus traditional lecture based formats develop equally strong physician-patient relationships, the rates of malpractice filings against graduates trained in each format at the John A. Burns' School of Medicine were compared. With the graduation of 10 more PBL classes, statistically significant differences between the two groups could be obtained.