Gender differences and influenza-associated mortality in hospitalized influenza A patients during the 2018/19 season

BACKGROUND

In this study we analyzed gender differences in the clinical presentation of patients with molecular confirmed influenza A. Additionally, we tried to identify predictors of influenza-associated mortality.

MATERIALS/METHODS

In this prospective observational multi-center-study we included all influenza-positive patients ≥ 18 years who were hospitalized and treated on flu-isolation-wards in three hospitals in Vienna during the 2018/19 influenza season. Diagnoses were made via Cobas^® Liat^® POCT.

RESULTS

490 Patients (48.8% female) tested positive for influenza A. Female patients were older (median age 76 years vs. 70 years, p < 0.001). Male patients had a higher rate of chronic liver disease in history (8.8% vs. 2.9%, p = 0.006), myositis (11.7% vs. 3.1%, p < 0.001) and ICU admissions (9.6% vs. 4.6%, p = 0.03). The in-hospital mortality rate was 4.3% and increased to 9.5% during the 90-day follow-up period. Female patients > 75 years had a significantly higher in-hospital mortality rate than ≤ 75-year-old females (9.2% vs. 1.7%, p = 0.019). This effect was not observed in male patients (5.4% vs. 1.9%, p = ns). Age > 75 years (OR 5.49, 95% CI 1.10-27.43), acute heart failure (OR 3.56, 95% CI 1.03-12.05) and ICU admission (OR 6.1, 95% CI 0.98-37.91) were predictors for in-hospital mortality for female patients, while any malignancy (OR 9.4, 95% CI 1.90-46.54) and ICU admission (OR 7.05, 95% CI 1.44-34.55) were predictors in male patients.

CONCLUSIONS

Gender is associated with differences in clinical presentation and complications of influenza A virus infection. Women with acute heart failure or aged > 75 years have an increased risk of influenza associated in-hospital mortality, while ICU admission and any malignancy are predictors for male patients. Mortality rates in patients > 75 years are 5-10 times higher compared to their non-hospitalized influenza-negative Austrian counterparts.

Severity of organ failure is an independent predictor of intracranial hypertension in acute liver failure

BACKGROUND & AIMS

Ionized ammonia (NH(3)) and partial pressure of the gaseous ammonia (pNH(3)) are associated with hepatic encephalopathy and intracranial hypertension in patients with acute liver failure; NH(3) is also believed to contribute to extrahepatic organ failure. We investigated whether the severity of organ failure was associated with intracranial hypertension and evaluated the correlation between NH(3) and pNH(3) and grade of hepatic encephalopathy.

METHODS

In 87 patients with acute liver failure admitted to the intensive care unit, we simultaneously evaluated arterial ammonia, pNH(3), clinical grade of hepatic encephalopathy, the sequential organ failure assessment score (SOFA score), and evidence of intracranial hypertension.

RESULTS

In comparing patients with intracranial hypertension (n = 37) with patients without intracranial hypertension (n = 50), the highest NH(3) and pNH(3) levels and SOFA scores before onset of intracranial hypertension were independent predictors of intracranial hypertension (P < .001). Among patients with NH(3) levels less than 146 mumol/L, those with intracranial hypertension had a higher SOFA score than those without intracranial hypertension (median, 10 vs 5.5; P = .004), despite the patients' similar levels of NH(3). NH(3) (r = 0.68, P < .0001) and pNH(3) (r = 0.78, P < .0001) both correlated with grade of hepatic encephalopathy. However, in multiple regression analysis, only pNH(3) (P < .0001) was shown to be a significant independent parameter for predicting grade of hepatic encephalopathy (P = .27).

CONCLUSIONS

SOFA score and ammonia levels are independent predictors of intracranial hypertension. In patients with acute liver failure admitted to the intensive care unit, pNH(3) level is a better predictor of clinical grade of hepatic encephalopathy than arterial NH(3) level.

Acute phase proteins do not account for unmeasured anions in critical illness

BACKGROUND

The increasingly recognized prognostic impact of the strong ion gap in critical illness is in contrast to its largely unknown chemical nature. Experimental and clinical evidence suggest that acute phase proteins might account for elevation of the strong ion gap. The hypothesis of this investigation was that acute phase proteins account for strong ion gap in critically ill patients.

MATERIALS AND METHODS

The charges of the two acute phase proteins C-reactive protein and fibrinogen were estimated by a computer model. Additionally, 142 patients admitted to a medical intensive care unit of a university hospital were studied prospectively during a six month period. Serial daily observations were recorded and classified according to the systemic inflammatory state. The acute phase proteins C-reactive protein and fibrinogen were measured and the strong ion gap was calculated from the measured acid-base variables.

RESULTS

The approximated mean charges of C-reactive protein and fibrinogen at a pH of 7.4 are -4.0 and -13.6 per molecule, respectively. Therefore, their negative charge is too small to explain the elevated strong ion gap even during a substantial increase of C-reactive protein and fibrinogen due to an acute-phase reaction. Moreover, C-reactive protein did not correlate with the strong ion gap when partialized for creatinine (R = 0.02, P = 0.567). Fibrinogen did not correlate with the strong ion gap. Creatinine correlated with the strong ion gap (R = 0.42, P < 0.001). Neither systemic inflammatory state nor increasing C-reactive protein levels were associated with an increasing strong ion gap.

CONCLUSION

Acute phase proteins do not account for an elevated strong ion gap in critically ill patients.

Acid-base disturbances in critically ill patients with cirrhosis

BACKGROUND/AIMS

The equilibrium of offsetting metabolic acid-base disorders in stable cirrhosis might be lost during episodes of hepatic decompensation, haemorrhage or sepsis. The purpose of this study was to determine whether the acid-base state is destabilized in critically ill patients with cirrhosis and whether this is associated with mortality.

PATIENTS AND METHOD

One-hundred and eighty-one consecutive patients with cirrhosis were investigated in a prospective observational cohort study on admission to a medical intensive care unit (ICU) of a university hospital. Arterial acid-base state was assessed according to the Gilfix methodology. Clinical data, ICU mortality and hospital mortality were recorded.

MAIN RESULTS

Patients had net metabolic acidosis owing to unmeasured anions and owing to hyperchloraemic, dilutional and lactic acidosis. Lactic acidosis, acidemia and acute renal failure on ICU admission were associated with increased mortality. Lactate and pH discriminated survivors from non-survivors. The presence of lactic acidosis could not always be recognized by customary acid-base parameters.

CONCLUSION

The stable equilibrium of acid-base disorders is lost when patients with cirrhosis become critically ill. Lactic acidosis and acidaemia are associated with increased ICU mortality caused by severe underlying organ dysfunction.

Time-dependency of sensory evoked potentials in comatose cardiac arrest survivors

OBJECTIVE

To assess the validity of early sensory evoked potential (SEP) recording for reliable outcome prediction in comatose cardiac arrest survivors within 48 h after restoration of spontaneous circulation (ROSC).

DESIGN AND SETTING

Prospective cohort study in a medical intensive care unit of a university hospital.

PATIENTS

Twenty-five comatose, mechanically ventilated patients following cardiopulmonary resuscitation

MEASUREMENTS AND RESULTS

Median nerve short- and long-latency SEP were recorded 4, 12, 24, and 48 h after ROSC. Cortical N20 peak latency and cervicomedullary conduction time decreased (improved) significantly between 4, 12, and 24 h after resuscitation in 22 of the enrolled patients. There was no further change in short-latency SEP at 48 h. The cortical N70 peak was initially detectable in seven patients. The number of patients with increased N70 peak increased to 11 at 12 h and 14 at 24 h; there was no further change at 48 h. Specificity of the N70 peak latency (critical cutoff 130 ms) increased from 0.43 at 4 h to 1.0 at 24 h after ROSC. Sensitivity decreased from 1.0 at 4 h to 0.83 at 24 h after ROSC.

CONCLUSION

Within 24 h after ROSC there was a significant improvement in SEP. Therefore we recommend allowing a period of at least 24 h after cardiopulmonary resuscitation for obtaining a reliable prognosis based on SEP.