The hemodynamic and respiratory effects of cuirass ventilation in healthy volunteers: Part 1.

OBJECTIVE: Negative-pressure ventilation (NPV) by external cuirass (RTX; Deminax Medical Instruments Limited, London, UK) in intubated patients after cardiac surgery improves hemodynamics measured by pulmonary artery catheter (PAC)-based methods, with an increased cardiac output (CO) and stroke volume (SV), without changing the heart rate (HR). The less-invasive pressure recording analytical method (PRAM) (Mostcare; Vytech Health srl, Padova, Italy) allows radial artery-based monitoring of the CO, SV, SV variation, and cardiac cycle efficiency (CCE). The authors investigated the hypothesis that NPV improves PRAM-based hemodynamics and arterial blood gas analysis in spontaneously breathing subjects. DESIGN: A clinical investigation. SETTING: A teaching hospital. PARTICIPANTS: Ten healthy volunteers. INTERVENTIONS: Subjects underwent 5 consecutive experimental ventilation modalities lasting 5 minutes: (1) baseline (no cuirass ventilation), (2) mode 1: cuirass ventilation with a continuous negative pressure of -20 cmH(2)O, (3) first rest period (no cuirass ventilation), (4) mode 2: cuirass ventilation in control mode of 12 breaths/min at -20 cmH(2)O, and (5) second rest period. MEASUREMENTS AND MAIN RESULTS: PRAM parameters were analyzed throughout the final minute of each experimental modality, which concluded with arterial blood gas sampling. Both NPV modes significantly reduced HR without changing CO or systemic vascular resistance. Mode 1 significantly increased CCE and decreased SVV. PO(2) decreased in both rest modes compared with baseline. This was prevented by NPV. In 5 smokers, PO(2) significantly increased in the control mode compared with first rest period. The control mode NPV improved oxygenation with a reduced PCO(2) and reciprocally increased pH. CONCLUSIONS: Five minutes of NPV improves hemodynamics and oxygenation in healthy subjects.

The hemodynamic and respiratory effects of continuous negative and control-mode cuirass ventilation in recently extubated cardiac surgery patients: Part 2.

OBJECTIVE: Negative-pressure ventilation (NPV) by external cuirass (RTX; Deminax Medical Instruments Limited, London, UK) in intubated patients after cardiac surgery improves hemodynamics measured by pulmonary artery catheter (PAC)-based methods with increased cardiac output (CO) and stroke volume (SV) without changing the heart rate (HR). The less-invasive pressure recording analytical method (PRAM) (MostCare; Vytech Health srl, Padova, Italy) allows radial artery monitoring of CO, SV, SV variation, and cardiac cycle efficiency (CCE). The authors investigated the hypothesis that NPV improves PRAM-based hemodynamics and arterial blood gas analysis in extubated cardiac surgery patients. DESIGN: A clinical investigation. SETTING: A teaching hospital. PARTICIPANTS: Twenty recently extubated cardiac surgery patients. INTERVENTIONS: Five consecutive experimental ventilation modalities lasted 5 minutes: (1) baseline (no cuirass ventilation), (2) mode 1 (cuirass ventilation with a continuous negative pressure of -20 cmH(2)O), (3) rest 1 (no cuirass ventilation), (4) mode 2 (cuirass ventilation in the control mode of 12 breaths/min at -20 cmH(2)O, and (5) rest 2. MEASUREMENTS AND MAIN RESULTS: PRAM parameters were analyzed throughout the final minute of each experimental modality, concluding with arterial blood gas sampling. NPV was well tolerated. HR was unchanged. Mode 2 SV was higher than baseline and rest 2. Mode 2 CO was higher than rest 2. Rest 2 systolic blood pressure was lower than rest 1 and mode 2. Increased CCE with NPV was not significant (p = 0.0696). Oxygenation and PCO(2) were unchanged although mode 2 pH increased. CONCLUSIONS: Extubated sedated cardiac surgery patients comfortably tolerated NPV with unchanged HR. SV and pH increased.

The value of an infectious diseases specialist.

Infectious diseases (ID) specialists have played a major role in patient care, infection control, and antibiotic management for many years. With the rapidly changing nature of health care, it has become necessary for ID specialists to articulate their value to multiple audiences. This article summarizes the versatile attributes possessed by ID specialists and delineates their value to patients, hospitals, and other integral groups in the health care continuum.

Fatal Outcome of Disseminated Strongyloidiasis despite Detectable Plasma and Cerebrospinal Levels of Orally Administered Ivermectin.

Strongyloides stercoralis affects over 100 million people worldwide. Those people most susceptible to infection are those with an immunocompromising condition, such as cancer or human immunodeficiency virus (HIV). Local disease may spread throughout the body of the host, causing a condition termed disseminated strongyloidiasis. Standard treatment for Strongyloides stercoralis infection is oral ivermectin. We describe a patient with chronic lymphocytic leukemia diagnosed with disseminated strongyloidiasis two weeks after initial presentation. After repeated dosing of oral ivermectin with no clinical response, serum and cerebral spinal fluid (CSF) concentrations of ivermectin were measured to assess absorption. The peak serum concentration of 49.3 ng/mL correlated with a CSF concentration of 0.14 ng/mL. Despite these concentrations, the patient eventually succumbed to multi-system organ failure. We discuss the reasons for treatment failure and explore the utility of measuring ivermectin concentrations.