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M L Caspani

Publications and source records attributed to M L Caspani.

6 recordsLinked to original sources
PubMed1984

The role of total static lung compliance in the management of severe ARDS unresponsive to conventional treatment.

A group of 36 patients with severe adult respiratory distress syndrome (ARDS) meeting previously established blood gas criteria (mortality rate 90%) became candidates for possible extracorporeal respiratory support [low frequency positive pressure ventilation with extracorporeal CO2 removal (LFPPV-ECCO2R)]. Before connecting the patients to bypass we first switched the patients from conventional mechanical ventilation with positive end expiratory pressure (PEEP) to pressure controlled inverted ratio ventilation (PC-IRV), and then when feasible, to spontaneous breathing with continuous positive airways pressure (CPAP). Forty eight hours after the patients had entered the treatment protocol, only 19 out of the 36 patients in fact required LFPPV-ECCO2R, while 5 were still on PC-IRV, and 12 were on CPAP. The overall mortality rate of the entire population was 23%. The only predictive value of success or failure of a particular treatment mode was total static lung compliance (TSLC). No patients with a TSLC lower than 25 ml (cm H2O)-1 tolerated either PC-IRV or CPAP, while all patients with a TSLC higher than 30 ml (cm H2O)-1 were successfully treated with CPAP. Borderline patients (TSLC between 25 and 30 ml (cm H2O)-1) had to be treated with PC-IRV for more than 48 h, or were then placed on LFPPV-ECCO2R if Paco2 rose prohibitively. We conclude that TSLC is a most useful measurement in deciding on the best management of patients with severe ARDS, unresponsive to conventional treatment.

Adolescent↗
PubMedDate not supplied

Heat stress: characteristics, pathophysiology and avoidable mistakes.

In August 2003 an exceptional heatwave was recorded in Europe. The authors would like to describe 6 patients for which the intensivist was called as a consultant. All patients had a skin temperature >40 degrees C, central nervous system impairment, severe hyponatremia [124.7 mEq/l+/-5.6 (range 117-130)] and severe metabolic acidosis [BE -6.28 mEq/l+/-3.55 (range -9.5-0), HCO3- 17.75 mEq/l+/-3.25 (range 13.4-21.9)]. All patients had decreased platelet count and coagulation abnormalities. Two patients were hypertensive, 4 hypotensive. The heat stress due to the hot environment is characterized by systemic inflammatory response (as in severe sepsis) and hemodynamic impairment (as in hypovolemic shock). The association between hypovolemia and altered microcirculation leads to cell energy failure with metabolic lactic acidosis. The energy failure may induce structural irreversible damage of mitochondria. It is possible to differentiate, during energy failure, the irreversible or reversible condition by volume loading and vasoactive drugs challenge tests. In fact, if the hemodynamic correction is associated with normalization of SvO2 with disappearance of metabolic acidosis, this suggests hemodynamic impairment with intact mitochondrial function. In contrast, if the hemodynamic improvement with normalization of SvO2 is associated and acidosis persists, this suggests irreversible structural mitochondrial damage. The threshold between reversibility and irreversibility is likely time dependent, as suggested by biochemical consideration and by 2 large randomized studies on hemodynamic treatment. The comparative analysis of these 2 studies suggests that the time of intervention may lead to significant differences in mortality. In these patients time is essential.

Acidosis, Lactic↗
PubMedDate not supplied

Constant mean airway pressure with different patterns of positive pressure breathing during the adult respiratory distress syndrome.

Twenty-one ARDS patients were divided into two groups of severity according to FIO2 and PEEP required to maintain an adequate gas exchange. The 10 most severe patients (group A) underwent continuous positive pressure ventilation (CPPV) (I/E 3:1) with the mean airway pressure maintained at 21 +/- 6.2 cmH2O. The PEEP values were 12.6 +/- 4.3 cmH2O during CPPV and 6.5 +/- 3.7 cmH2O during IRV (p less than 0.01). Eleven less severe ARDS patients (group B) underwent CPPV and positive pressure spontaneous breathing (CPAP) at constant mean airway pressure of 14.3 +/- 3.8 cmH2O. The PEEP was 7 +/- 2.5 cmH2O during CPPV and 14.9 +/- 4.3 cmH2O during CPAP (p less than 0.001). In five patients of each group, the SF6 shunt was measured as representative of true shunt. The results showed that gas exchange, including true shunt, and haemodynamics did not change between CPPV and IRV and between CPPV and CPAP tests. Taken with previous work on mean airway pressure, our results further support the concept that the main determinant of oxygenation and haemodynamics is the mean airway pressure, irrespective of the PEEP level and of the mode of ventilation.

Adolescent↗