Abstract

Resistance to parenteral antimicrobials generally occurs within two years after introduction into general use. The site where de novo resistance develops has been acknowledged to be the gut. Overgrowth of abnormal flora, defined as 105 potential pathogens per g of faeces is a risk factor for resistance following increased spontaneous mutation leading to polyclonality and antimicrobial resistance. As parenteral antimicrobials generally fail to eradicate the abnormal carrier state in overgrowth concentrations due to sub-lethal concentrations in bile and mucus the enteral antimicrobials polymyxin/tobramycin aiming at converting the abnormal carrier state into normal carriage, are the essential component of selective decontamination of the digestive tract (SDD), because they eradicate carriage and overgrowth including resistant mutants, maintaining the usefulness of parenteral antimicrobials.

Keywords: normal carriage, abnormal carriage, overgrowth, mutation, polyclonality, resistance, selective decontamination of the digestive tract, parenteral antimicrobials, enteral antimicrobials

Abstract

The fact that different modalities of mechanical ventilation are associated with a number of serious side effects and risks and can influence the clinical outcome of patients, the various modes of mechanical ventilation have, over the past ten years, been the subject of a wide variety of scientific studies. Many of these modalities are designed for partial ventilatory support, which might reflect the complexity of the issue of patient's ventilator interactions when spontaneous breathing activity is present, compared to controlled mechanical ventilation. Spontaneous breathing modes during mechanical ventilation may integrate intrinsic feedback mechanisms that should help prevent ventilator- induced lung injury and improve synchrony between the ventilator and the patient's demand. The improvements in pulmonary gas exchange, systemic blood flow, and oxygen supply to the tissue that have been observed when spontaneous breathing has been maintained during mechanical ventilation are reflected in the clinical improvement in the patient' s condition. It is the aim of this article to review the effects of preserved spontaneous breathing activity during mechanical ventilation in patients with acute respiratory failure.

Key words: mechanical ventilation, acute respiratory distress syndrome, ventilation mode, spontaneous breathing

Abstract

Some case reports and case series suggest that protein C concentrates may improve the outcome in patients with congenital or acquired protein C deficiency (not only in those with sepsis induced purpura fulminans). We reviewed the published literature on the use of protein C concentrates in adult septic patients and found that it is limited to less than 70 patients reported in observational studies with a 70% survival, and added our personal experience (two adult patients with sepsis and contraindications to recombinant activated protein C).

Key words: sepsis, protein C, cardiac surgery

Abstract

Perioperative cardiac arrests represent the most serious complication of anesthesia and surgery. It is believed that the incidence and mortality of cardiac arrest has declined, however, a more recent review questioned whether these rates have changed over the last 5 decades. It is difficult to compare the reports from different epochs, because medical practice has advanced, surgical acuity increased, and patients in extremes of age undergo surgery today. In the present article we review the information regarding the incidence of perioperative cardiac arrests and predictors of survival covering the period since the first comprehensive report by Beecher and Todd in 1954. We focus on our publications that report perioperative cardiac arrest at Mayo Clinic for adult noncardiac surgery, during regional anesthesia, and arrests in our pediatric surgical practice.

Key words: anesthesia, cardiac arrest, mortality

The underlying mechanism of cell injury during ischemia and reperfusion is complex and timesesnsitive. Some processess develop coincidentally with the onset of ischemia and during reperfusion leading to abnormalities in energy metabolism, acid base status, and intracellular ion homeostasis. Other processes develop later and encompass activation of various signalling pathways that have deleterious or beneficial effects on specific effectors, but associated with sustained disruption of energy production contractile dysfunction and activation of apoptotic pathways. Discussion on the various cell mechanisms resposible for cell injury is beyond the scope of this review. However, pertinent to our discussion is the mounting evidence pointing to mitochondria as key target organelles of reperfusion injury.

Key words: cardiac arrest, mito-chondrial injury, cardiopulmonary resuscitation, apoptosis