Surgery
-
Pain that cannot be controlled by traditional oral and parenteral methods in those patients with advanced cancer can be alleviated by spinal administration of narcotics. Epidural and intrathecal infusion with morphine causes analgesia by blocking spinal receptors without significant long-term central nervous, gastrointestinal, and genitourinary system effects. Of the total of 33 patients, epidural catheters inserted in 20 patients then connected by a subcutaneous tunnel to a continuous infusion system. ⋯ Patient assessment by a linear analogue scale to measure pain levels determined that 23 of the 33 total patients (70%) had excellent or good relief of pain. The delivery of spinal administration of narcotics to treat intractable cancer pain in patients is safe. Most importantly, this method of delivery can be used in community hospitals, in outpatient settings, and in home health care programs.
-
Translocation of enteric bacteria occurs in rats after hemorrhagic shock. A proposed mechanism involves intestinal mucosal injury by hypoperfusion. Recent work suggests that moderate hypovolemia causes gut arteriolar constriction, which is ameliorated by hypertonic saline resuscitation. ⋯ Statistical analysis used the Fisher exact test. Compared to autotransfusion, hemodilutional resuscitation from hemorrhagic shock with hypertonic saline resulted in a significant reduction in bacterial translocation (p values were 0.03 and 0.04 for 3% and 7.5% hypertonic saline, respectively). The reduction in translocation after hypertonic saline resuscitation may be the consequence of microcirculatory alterations preventing gut hypoperfusion.
-
We tested the hypothesis that, after aortotomy, rapidly replacing three times the blood volume deficit with intravenous crystalloid will increase hemorrhage and decrease survival. Sixteen anesthetized Yorkshire swine underwent splenectomy and stainless steel wire placement in the infrarenal aorta and were instrumented with pulmonary artery and carotid artery catheters. ⋯ The volume of hemorrhage and the mortality rate were significantly increased (p less than 0.05) in the treatment group receiving lactated Ringer's solution relative to the control animals (2142 +/- 178 ml versus 783 +/- 85 ml, and eight of eight animals versus zero of eight animals, respectively). From these data we conclude that, in this model of uncontrolled arterial hemorrhage resulting from abdominal aortotomy, rapidly administering lactated Ringer's solution intravenously significantly increases hemorrhage and death.
-
We addressed the impact on intracranial pressure (ICP) of posthemorrhage fluid resuscitation with a protocol in which additional fluid was infused to maintain a stable cardiac output after an initial bolus of fluid was infused. Anesthetized, mechanically ventilated mongrel dogs (n = 27) underwent a 30-minute interval of hemorrhagic shock (mean arterial pressure = 55 mm Hg) during which inflation of a subdural balloon maintained ICP at 15 mm Hg. After shock, animals were resuscitated with one of four randomly assigned fluids: (1) slightly hypotonic crystalloid (Na+, 125 mEq. ⋯ Cerebral blood flow, measured by the cerebral venous outflow method, increased immediately after resuscitation and then declined steadily over time in all groups. Fluids containing pentastarch maintained hemodynamic stability with minimal supplementation throughout most of the postresuscitation period, compared with crystalloid alone, which required substantial additional volume. If decreased intracranial compliance and hemorrhage are combined, ongoing resuscitation is associated with significantly increased ICP and significantly decreased cerebral blood flow, independent of the tonicity and oncotic pressure of the infused fluid.
-
We studied the intestinal microvascular blood flow responses to hemorrhage and resuscitation with pentoxifylline by in vivo video microscopy. Male Sprague-Dawley rats were hemorrhaged to 50% of baseline mean arterial pressure for 45 minutes and then blindly randomized to receive pentoxifylline (25 mg/kg bolus + 0.2 mg/kg/minute) or an equivalent volume of saline plus return of shed blood and an additional bled volume of Ringer's lactate solution. Hemorrhage caused intestinal microvascular blood flow to decrease to 10% to 15% of baseline values. ⋯ In contrast, addition of pentoxifylline to the resuscitation regimen resulted in an immediate hyperemic response with an increase in intestinal microvascular blood flow to significantly greater than baseline values followed by return to baseline. Arteriolar dilation was not responsible for the improvement in flow implicating improved flow dynamics between erythrocytes, granulocytes, and vascular endothelia within the microcirculation. We conclude that addition of pentoxifylline to resuscitation from hemorrhagic shock restores intestinal microvascular blood flow.