Effect Of Hypotensive Anesthesia Research Articles

The Effect of Hypotensive Anesthesia on Hemoglobin Levels during Total Knee Arthroplasty.

Introduction: Hypotensive epidural anesthesia (HEA) is used in total joint arthroplasty as a safe and effective blood-saving modality. In order to maintain the blood pressure and heart rate patients, receive 1000 to 1500 mL of lactated Ringer’s solution during surgery. While HEA reduces the intraoperative blood loss, the effect of intravenous fluid loading on hemoglobin levels is not fully understood. The current study investigates the effect of HEA on perioperative hemoglobin levels. Materials and Methods: The study included 35 patients operated on by a single surgeon undergoing primary total knee arthroplasty under HEA. Intraoperatively, at least 300 mL of intravenous fluid were given every 15 min over the first 60 min after HEA. Blood samples were drawn before entering the operating room, after HEA, as well as after inflation of the tourniquet, every 15 min thereafter, as well as in the recovery room and on postoperative days one and two. In addition, fluid in- and outtake was recorded. Results: Patients received a mean 1275 mL during the 60 min of tourniquet time. The mean arterial pressure (MAP) 5 min after HEA dropped to 60 mmHg and reached a constant level of around 58 mmHg 15 min after HEA. The average hemoglobin level dropped from 13.9 g/dL prior to HEA, to 12.5 g/dL immediately after HEA (p < 0.001). Intraoperatively the hemoglobin level dropped further and reached 11.8 g/dL at 60 min in the absence of blood loss. Conclusions: Hypotensive epidural anesthesia and the resulting fluid substitution resulted in an average hemoglobin drop of 2.1 g/dL within the first 60 min. This needs to be taken into account when evaluating the need for blood transfusions after primary joint replacement surgery under HEA.

Effect of Hypotensive Anesthesia on Cerebral Perfusion and Blood Antioxidant Levels and HIF 1a

Effect of Hypotensive Anesthesia on Cerebral Perfusion and Blood Antioxidant Levels and HIF 1a

Comparative Effect of Hypotensive Anaesthesia on Event Related Potentials, Quantitative Electroencephalograghy

Comparative Effect of Hypotensive Anaesthesia on Event Related Potentials, Quantitative Electroencephalograghy

Effects of Hypotensive Anesthesia on Blood Transfusion Rates in Craniosynostosis Corrections

Hypotensive anesthesia is routinely used during craniosynostosis corrections to reduce blood loss. Noting that cerebral oxygenation levels often fell below recommended levels, the authors sought to measure the effects of hypotensive versus standard anesthesia on blood transfusion rates. One hundred children undergoing craniosynostosis corrections were randomized prospectively into two groups: a target mean arterial pressure of either 50 mm Hg or 60 mm Hg. Aside from anesthesiologists, caregivers were blinded and strict transfusion criteria were followed. Multiple variables were analyzed, and appropriate statistical testing was performed. The hypotensive and standard groups appeared similar, with no statistically significant differences in mean age (46.5 months versus 46.5 months), weight (19.25 kg versus 19.49 kg), procedure [anterior remodeling (34 versus 31) versus posterior (19 versus 16)], or preoperative hemoglobin level (13 g/dl versus 12.9 g/dl). Intraoperative mean arterial pressures differed significantly (56 mm Hg versus 66 mm Hg; p < 0.001). The captured cell saver amount was lower in the hypotensive group (163 cc versus 204 cc; p = 0.02), yet no significant differences were noted in postoperative hemoglobin levels (8.8 g/dl versus 9.3 g/dl). Fifteen of 100 patients (15 percent) received allogenic transfusions, but no statistically significant differences were noted in transfusion rates between the hypotensive [nine of 53 (17.0 percent)] and standard anesthesia [six of 47 (13 percent)] group (p = 0.056). No significant difference in transfusion requirements was found between hypotensive and standard anesthesia during craniosynostosis corrections. Considering potential benefits of improved cerebral blood flow and total body perfusion, surgeons might consider performing craniosynostosis corrections without hypotension. Therapeutic, II.

Effect of hypotensive anaesthesia on cognitive functions: a comparison of Esmolol and Remifentanil during tympanoplasty

Celebi, N.; Artukoglu, F.; Dal, D.; Saricaoglu, F; Celiker, V.; Aypar, U. Author Information

The effect of hypotensive anaesthesia on cognitive functions and recovery at endoscopic sinus surgery

The effect of hypotensive anaesthesia on cognitive functions and recovery at endoscopic sinus surgery

The effect of hypotensive anesthesia on blood loss and operative time during Le Fort I osteotomies

Purpose: The purpose of this prospective study was to compare the quality of the surgical field, blood loss, and operative time with either hypotensive or normotensive anesthesia during Le Fort I osteotomies. Patients and Methods: Twenty-three patients were randomized into normotensive or hypotensive anesthesia treatment groups. The quality of the surgical field was assessed intraoperatively by direct observation and again postoperatively using video imaging. A standardized rating scale was applied at specific intervals by surgeons blinded to the anesthetic technique. The surgical time was measured on the videotape, and blood loss was measured by volumetric and gravimetric techniques. Results: There was a statistically significant correlation (P<.0001) between the surgeon's perception of the quality of the surgical field and the blood pressure. There was also a statistically significant reduction (P<.01) in blood loss when using hypotensive anesthesia. However, there was no statistically significant reduction (P=.44) in operative time when using hypotensive anesthesia. Conclusions: It was concluded that hypotensive anesthesia is valuable in reducing blood loss and improving the quality of the surgical field during Le Fort I osteotomies, allowing for easier, more deliberate, and careful dissection. However, it does not reduce operative time. © 2000 American Association of Oral and Maxillofacial Surgeons

Effects of hypotensive anesthesia, nonsteroidal antiinflammatory drugs, and polymethylmethacrylate on bleeding in total hip arthroplasty patients

One hundred forty patients ranging in age from 26 to 88 years, who had primary total hip arthroplasty (performed by the same surgeon and lateral surgical approach), were analyzed for intraoperative and postoperative blood loss. The factors affecting blood loss, which include bleeding disorders, medications, duration of surgery, the mean intraoperative blood pressure, and use of cement, were all recorded. A significant reduction in the intraoperative blood loss was observed in the group of patients with hypotensive anesthesia (>20 mmHg drop in the mean intraoperative blood pressure using inhalation anesthetics) compared to the group of patients who did not have hypotensive anesthesia. The patients who had been on aspirin or nonsteroidal antiinflammatory drugs prior to surgery had increased intraoperative and postoperative blood loss compared to the patients who did not take such medications. The effect of cementing with methylmethacrylate on bleeding was also observed; the patients with uncemented implants had a greater blood loss after operation than the patients who had cemented prosthetic components.

The Effect of Hypotensive Anesthesia on Cephalosporin Concentrations in Serum, Soft Tissue, and Bone

The objective of this study was to determine the efficacy of a hypotensive anesthetic in enhancing tissue perfusion while simultaneously controlling surgical blood loss. One hundred ten patients undergoing 126 total hip arthroplasties were administered either cephalothin or cefamandole on a double-blind basis. Hypotensive anesthesia was administered to 64 patients; 46 received a normotensive anesthetic. Degree of tissue perfusion was measured by the concentration of cephalosporin found in samplings of serum, soft tissue, and bone. These samples, obtained during the course of total joint arthroplasty, indicate that the hypotensive anesthetic sodium nitroprusside did not significantly alter the concentrations of cefamandole or cephalothin from those found in the normotensive group.

The effect of hypotensive anesthesia on cephalothin concentrations in bone and muscle of patients undergoing total hip replacement.

Serial blood, muscle, and bone concentrations of cephalothin following intravenous infusion were determined in forty-eight patients during total hip replacement. Thirty patients received hypotensive anesthesia and the remaining eighteen received anesthesia without induced hypotension. The concentrations of cephalothin were determined during the first (early) and second (late) hours of the operation. Late serum levels were lower in the patients who had induced hypotension. In all patients at least one bone specimen contained measurable amounts of cephalothin. When pentolinium (Ansolysen) was used to induce hypotension, the late serum and early bone cephalothin concentrations were lower, while use of trimethaphan (Arfonad) did not appear to result in lower cephalothin concentrations in serum, muscle, or bone compared with patients with normotensive anesthesia.

The effect of hypotensive anesthesia on renal hemodynamics

Deliberate hypotensive anesthesia (MBP = 36 mm Hg) using Halothane, hyperventilation, and positive pressure respiration (peak inspiratory pressure = 15 cm H 2O) was used in 7 dogs for a 2-hr period. Xenon-133 washout was employed by injection of 800–1500 μCi through a catheter placed under fluoroscopic control in the right renal artery. Washout curves were obtained before hypotensive anesthesia, during and after a return of normal hemodynamics using a collimater placed over the right flank. The curves were analyzed and total renal blood flow plus four components of renal blood flow were developed: I cortex; II juxtamedulla; III inner medulla; and IV hilar fat. Using an indocyanine green indicator dilution curve, cardiac output was measured. Urinary output was collected and blood gases monitored. Total renal blood flow decreased significantly during hypotensive anesthesia only to return toward normal within 30 min of discontinuing deliberate hypotension (328 control → 159 during hypotensive anesthesia → 227 ml/100 g/min after hypotensive anesthesia). This decrease in renal blood flow was associated with a fall in cardiac output which also returned toward normal promptly after discontinuing inhalation anesthesia (3.2 → 1.7 → 3.0 liter/min). The ratio of renal blood flow/cardiac output did not change with hypotensive anesthesia indicating an absence of renal vasoconstriction, and renal vascular resistance actually fell from .427 to .306 mm Hg/ml/100 g/min. During the recovery phase, because the blood pressure and cardiac output returned to the control level before renal blood flow, the ratio of renal blood flow/cardiac output fell from 7.1 to 4.9% and the renal vascular resistance rose from .306 to .611 mm Hg/ ml/100 g/min. It was apparent that during recovery renal vasoconstriction developed. The fall in renal blood flow with hypotensive anesthesia was associated with a significant fall in Component I (cortical) flow (414 → 257 → 330 ml/100 g/min) but no significant change in Component II (outer medullary) flow (72 → 74 → 98 ml/ 100 g/min) or the percent distribution of radioactivity between cortex and medulla. This indicates a selective decrease in cortical flow and an absence of marked intrarenal shunting which is seen with hypovolemic hypotension. Urine output fell during hypotension (65 → 20 → 80 ml/hr) but did not cease entirely in any animal. The explanation for the known renal safety of hypotensive anesthesia rests primarily with the absence on intrarenal shunting and associated vasoconstriction during hypotension.

CONCLUSIONS: Effect of Hypotensive Anesthesia as Seen from Results of Present Study

CONCLUSIONS: Effect of Hypotensive Anesthesia as Seen from Results of Present Study