Blood viscosity during anaesthesia with halothane, cyclopropane, thiopentone and ketamine

Comparing effects of low and high-flow anesthesia on hemorheology and coagulation factors

OBJECTIVES

In the current study, we compared the effects of low- and high-flow anesthesia techniques on hemorheology and coagulation parameters in patients who received sevofluran.

METHODS

Forty patients classified as Risk Group I-II according to American Society of Anesthesiologists' (ASA) guidelines who were scheduled to undergo general anesthesia were randomly assigned to one of two groups. Low-flow anesthesia was administered to the first group, and high-flow anesthesia was used in the second group. Blood samples were obtained in the preoperative and peroperative periods (at 60 and 120 min) for determination of blood and plasma viscosity, plasma oncotic pressure, international normalized ratio (INR), phorotrombin time (PT), activated partial phorotrombin time (aPTT) and fibrinogen. Blood was also drawn for analysis of factor VIII (FVIII) activity, which was measured in the preoperative period and at postoperative six hour.

RESULTS

The peroperative plasma viscosity was significantly low in Group 1 relative to Group 2. aPTT was significantly elevated at 60 minutes in Group 1 relative to Group 2, but the increase at 120 minutes was not significant.

CONCLUSION

The effects of low-flow anesthesia on hemorheology were greater than those of high-flow anesthesia.

Solitary pulmonary metastasis: an enigma

Lung metastases, which are an expression of the new phase of the underlying neoplastic disorder, have been treated in the recent years by multiple disciplinary approach. When the metastases to the lungs are multiple, it is indicative of extensive tumor burden, and the organ plays an insignificant role in the distribution of the metastases in the different lobes of the lungs. However, when the pulmonary metastases appear after a prolonged disease-free interval it becomes an enigma; when the metastases are solitary, the majority (over 80% in this series) are located in the upper zone of the lungs. This study of 28 patients with solitary lung metastases explores the possible etiology of this clinical observation and proposes that the pattern of perfusion and anatomopathological features of the upper lobes are the main reasons why these lobes are prevalently the sites for solitary lung metastases.