Rohrer's constant, K2, as a factor of determining inspiratory resistance of common adult endotracheal tubes.

The aim of the study was to calculate the in vitro inspiratory resistance (R(ETT)) of adult endotracheal tubes (ETT), via the end-inspiratory occlusion method, and to apply this method in vivo in order to estimate R(ETT) value in real time. By plotting R(ETT) over inspiratory flow (V) and calculating Rohrer's coefficients of linear and nonlinear resistance, K1 and K2 respectively, we determined the resistive behaviour of each ETT. Peak and plateau pressures were recorded at both proximal and distal sites of the ETT after applying a three-second occlusion under constant flow. Distal pressure was obtained via an intraluminal catheter R(ETT) was calculated as (P(peak) - P(plateau))/(V), at both sites. R(ETT) value resulted from the difference R(proximal) - R(distal). Graph R(ETT) over (V) was plotted and Rohrer's constants were calculated by the method of least squares. For ETTs with inner diameter 9.0, 8.5, 8.0, 7.5, 7.0 and 6.5 mm, K2 was 2.42, 3.05, 4.65, 6.01, 9.17 and 12.80 cmH2O/l/s, respectively. The intraluminal catheter increased R(ETT) No.7.0 by an average of 49%. Finally, ten patients with partially obstructed ETTs were tested and K2 in vivo constants found to be higher than their corresponding in vitro values (P value 0.00012). Therefore, knowing the performing size of an ETT may help the clinicians identify ETT obstruction and deal with weaning problems.

Combined hepatocellular-cholangiocarcinoma presented with massive pulmonary embolism.

A 30-year-old HBsAg-positive woman was admitted to the hospital because of 6 days of progressive shortness of breath. She was in severe respiratory distress with circulatory collapse. She had an enlarged liver but no stigmata of chronic liver disease or signs of cirrhosis. She had rapidly developed respiratory arrest and was transferred to intensive care unit. Heart ultrasonography and Doppler scan showed right heart straining and high pulmonary artery pressure. Despite cardiovascular and respiratory support she died a few hours after admission. Autopsy revealed combined hepatocellular-cholangiocarcinoma infiltrating the entire liver, metastatic invasion of lung blood vessels and absence of right ventricular hypertrophy. The incidence of hepatocellular-cholangiocarcinoma, a variant of hepatocellular carcinoma, is roughly 2-3% and the presenting symptoms are abdominal pain, weight loss, jaundice, fever or decompensation of liver disease. Associated HBsAg positivity and cirrhosis are reported in 20-30% and 60% of patients, respectively. Metastases to lungs are relatively frequent but this is the first report of hepatocellular-cholangiocarcinoma presented with acute respiratory distress due to massive pulmonary embolism.

Bacterial sepsis-induced rhabdomyolysis.

OBJECTIVE: To describe the syndrome of rhabdomyolysis during bacterial sepsis with regard to incidence, blood bacteriology and complications and to examine the association between hyperosmolal state and rhabdomyolysis, evaluating the relationship between plasma osmolality (Posm) and serum creatine phosphokinase (CPK) levels. DESIGN: Prospective study including all patients admitted to the intensive care unit (ICU) for sepsis with positive blood culture and rhabdomyolysis over a 3-year period. SETTING: Seven-bed medical/surgical ICU of a teaching hospital. PATIENTS: 35 patients (group 1) with bacterial sepsis-induced rhabdomyolysis (15 males, 20 females; mean age 71+/-13 years) and 122 (group 2) bacteraemic septic patients without rhabdomyolysis (49 males, 73 females; mean age 68+/-15) were studied. Patients with rhabdomyolysis were divided into gram(+) and gram(-) subgroups according to the blood culture growth. RESULTS: From 491 patients recorded, 35 fulfilled the inclusion criteria for bacterial sepsis-induced rhabdomyolysis (7.1%). Gram-positive bacteria predominated in group 1 (69%), while gram-negative predominated (60%) in group 2. There was a correlation between CPK and Posm levels in the rhabdomyolysis Group (r = 0.52, R2 = 0.27, p = 0.003). There was a stronger correlation between these two variables (r = 0.67, R2 = 0.45, p = 0.001) in the gram(+).subgroup. Acute renal failure (68.5%) and electrolyte disorders such as hyperkalaemia (34%) and hypocalcaemia (48.5%) were the major complications in the rhabdomyolysis group. Sixteen (45.7%) patients in group 1 and 49 (40%) in group 2 died during their stay in the ICU from sepsis and multiple organ failure. Rhabdomyolysis was not considered a contributing factor to their death, as none of our patients died during or immediately after the syndrome. CONCLUSION: Bacterial sepsis-induced rhabdomyolysis results from certain types of microorganisms, mainly gram-positive and to a lesser extent gram-negative. Hyperosmolality is a predisposing mechanism for rhabdomyolysis during bacteraemic sepsis from any type of bacterial microorganism.

Reversal of liver failure in sickle cell vaso-occlusive crisis.

A severe but unusual complication of sickle cell vaso-occlusive crisis is acute liver failure related to intrahepatic cholestasis. The outcome is usually fatal in adults. A case of reversible acute liver failure in a patient with s/beta+ thalassemia is reported. The patient was admitted to the intensive care unit because of major organ failure related to vascular occlusion phenomena. After blood-plasma transfusion and supportive therapy for acute liver failure, complete recovery was noted. A liver biopsy performed at the stage of recovery was compatible with intrahepatic cholestasis and sickling. Even though patients with s/beta+ thalassemia usually manifest milder symptoms, they rarely develop major organ failure such as acute liver failure.

Multiple systems organ failure from organophosphate poisoning.

A 68-year-old man was admitted to an intensive care unit after a suicidal ingestion of dimethoate with organophosphate poisoning. Despite temporary improvement, the patient's condition progressively deteriorated with the development of adult respiratory distress syndrome and acute renal failure. Hemodynamic measurements substantiated the evidence of non cardiogenic pulmonary edema, while renal indices the presence of acute tubular necrosis. Despite vigorous organ specific support the patient died on the 12th hospital day. An autopsy confirmed the presence of adult respiratory distress syndrome and acute tubular necrosis. Organophosphate poison can be added to the list of toxins that caused adult respiratory distress syndrome and acute tubular necrosis and provoked the development of multiple systems organ failure.