Comparison of labetalol and lidocaine in induction of controlled hypotension in tympanoplasty: a randomized clinical trial.

OBJECTIVES: This study aimed to compare the efficacy of labetalol and lidocaine in tympanoplasty surgery, specifically evaluating their impact on hemodynamic changes and perioperative outcomes. METHODS: A randomized controlled trial was conducted with 64 patients scheduled for tympanoplasty. Patients were randomly assigned to receive either 0.5-2 mg/min labetalol or 1.5 mg/kg/h lidocaine 1% to achieve controlled hypotension during surgery. The efficacy of the drugs was assessed by comparing the Mean Arterial Pressure (MAP), surgeon's satisfaction, time to target MAP, bleeding volume, postoperative pain scores, the need for analgesic medication in recovery, sedation, and other additional parameters. RESULTS: The hemodynamic parameters showed a similar trend over time in both the labetalol and lidocaine groups. The median bleeding volume in the labetalol group (10 cc) was lower than that in the lidocaine group (30 cc), although this difference was not statistically significant (p = 0.11). Similarly, surgeon's satisfaction level, pain intensity, and sedation level in the recovery room did not show statistically significant differences between the two groups (p > 0.05). The duration of surgery, recovery stay, and extubation time also did not significantly differ between the groups. Both medications took approximately the same time (20 min) to reach the target MAP and exhibited comparable hemodynamic responses (p > 0.05). CONCLUSION: Both labetalol and lidocaine effectively achieved controlled hypotension during tympanoplasty surgery, thereby improving surgical conditions. The choice of medication should be based on individual patient characteristics and the anesthesiologist's judgment. LEVEL OF EVIDENCE: II.

Effects of controlled hypotension with restrictive transfusion on intraoperative blood loss and systemic oxygen metabolism in elderly patients who underwent lumbar fusion.

BACKGROUND: The effects of restrictive fluid therapy combined with controlled hypotension in the elderly on systemic oxygen metabolism and renal function are clinical concerns. The aim of this study was to evaluate blood loss, oxygen metabolism, and renal function in different levels of controlled hypotension induced by intravenous nitroglycerin, in combination with limited infusion, in elderly patients undergoing posterior lumbar fusion. METHODS: A total of 40 patients, aged 60-75 with ASA grade II or III, who were planned for posterior lumbar fusion were randomly allocated into two groups: experimental group [target mean arterial pressure 65 mmHg (MAP 65) or control group (MAP 75)]. Indicators for blood loss, hemodynamic, systemic oxygen metabolism, and renal function evaluation index were recorded before operation (T0), 1 h after induced hypotension (T1), 2 h after hypotension (T2), and in recovery (T3). We compared changes in these parameters between groups to evaluate the combined effects of controlled hypotension with restrictive infusion. RESULTS: CI, DO2I, and VO2I were lower in both groups at T1-T3 compared with T0 (p < 0.05). DO2I and VO2I in the MAP 65 group were lower than the MAP 75 group after operation. In both groups, SCysC increased at T1, T2, and T3 (p < 0.05) compared with T0. CONCLUSIONS: Restrictive transfusion and control MAP at 65 mmHg can slightly change in renal function and reduce the risk of insufficient oxygen supply and importantly have no significant effect on blood loss and postoperative complications. TRIAL REGISTRATION: ChiCTR-INR-16008153 . Registered on 25 March 2016.

Use of Adenosine to Facilitate Localization and Repair of Internal Carotid Artery Injury during Skull Base Surgery: A Case Report and Literature Review.

BACKGROUND: Internal carotid artery (ICA) injuries represent a rare, potentially fatal complication of endoscopic endonasal skull base surgery (EESBS). The use of adenosine to induce transient hypotension and facilitate management of high-flow, high-pressure arterial lesions has been well-documented in neuro-endovascular literature. A similar setting in which adenosine-induced hypotension may prove beneficial is during the management of major vascular injury encountered during EESBS. METHODS: A case of ICA injury and subsequent repair during EESBS is presented. RESULTS: A 74-year-old female underwent endoscopic transsphenoidal resection for a recurrent pituitary adenoma. During suprasellar resection, the right cavernous ICA was inadvertently injured resulting in brisk bleeding. Immediate vascular tamponade was applied, and a crushed muscle graft was obtained. Two intravenous doses of adenosine were administered in quick succession to produce transient hypotension and facilitate repair of the injury with the graft. Neurovascular imaging revealed a small pseudoaneurysm which remained stable throughout the postoperative course. The patient underwent definitive stent embolization of the pseudoaneurysm 1 month following discharge. CONCLUSION: Prompt repair of ICA injury during EESBS is crucial, but often limited by poor visualization. Adenosine-induced hypotension has demonstrated great efficacy as an adjuvant in neurovascular clipping of intracranial aneurysms and remains a valuable tool for the endoscopic skull-base surgeon as well. In cases with high risk for ICA injury, adenosine should be readily available.

Effects of perioperative magnesium sulfate with controlled hypotension on intraoperative bleeding and postoperative ecchymosis and edema in open rhinoplasty.

PURPOSE: This randomized, double-blind study was planned to evaluate the effect of perioperative magnesium sulfate with controlled hypotension on intraoperative bleeding, postoperative ecchymosis and edema, and side-effects. MATERIALS AND METHOD: Forty-nine patients undergoing open rhinoplasty were divided into two groups - magnesium sulfate and control. The magnesium sulfate group received 30-50 mg·kg-1 intravenously as a bolus before induction of anesthesia, followed by 10-20 mg·kg-1 h-1 by continuous intravenous infusion during surgery. Anesthesia was induced with propofol 3 mg·kg-1, fentanyl 15 µg·kg-1 and cisatracurium 0.6 mg·kg-1. Mean arterial pressure was maintained at 50 to 60 mmHg under controlled hypotensive anesthesia with magnesium sulfate titration. Hemodynamic variables, operational bleeding, early postoperative side-effects and postoperative first-, third- and seventh-day ecchymosis and edema were compared between the groups. Ecchymosis and edema were evaluated using a graded scale from 0 to 4. RESULTS: In the magnesium sulfate group, mean arterial pressure decreased during most of the perioperative period. Intraoperative bleeding also decreased. A distinct reduction in ecchymosis and edema was observed in both the upper and lower eyelids on the first, third and seventh days. Patients in the magnesium sulfate group also had a more peaceful postoperative course with less postoperative nausea vomiting, and shivering. CONCLUSION: Magnesium sulfate with controlled hypotension can lower ecchymosis and edema of the upper and lower eyelids in rhinoplasty surgery by reducing bleeding.

Effects of nitroglycerin versus labetalol on peripheral perfusion during deliberate hypotension for sinus endoscopic surgery: a randomized, controlled, double-blinded trial.

BACKGROUND: Deliberate hypotension is used to provide a bloodless field during functional endoscopic sinus surgery; however, the impact of controlled hypotension during anesthesia on peripheral tissue perfusion has not been extensively evaluated. The aim of this study was to compare the impact of nitroglycerin- versus labetalol-induced hypotension on peripheral perfusion. METHODS: The present randomized, double-blinded, controlled trial included adult patients undergoing endoscopic sinus surgery. Patients were allocated to one of two groups according to the drug received for induction of deliberate hypotension: nitroglycerin (n = 20) or labetalol (n = 20). Mean arterial pressure was maintained at 55-65 mmHg in both groups. Both study groups were compared according to pulse oximeter-derived peripheral perfusion index (primary outcome), serum lactate level, mean arterial pressure, heart rate, surgical field score, and intraoperative blood loss. RESULTS: Forty patients were included in the final analysis. The nitroglycerin group exhibited a higher peripheral perfusion index at nearly all records (p < 0.0001) and lower postoperative serum lactate levels (1.3 ± 0.2 mmol/L vs. 1.7 ± 0.4 mmol/L; p = 0.001) than the labetalol group. The peripheral perfusion index was higher in the nitroglycerin group than at baseline at most intraoperative readings. The median surgical field score was modestly lower in the labetalol group than in the nitroglycerin group in the first 20 min (2 [interquartile range (IQR) 2-2.5] versus 1.5 [IQR 1-2]; p = 0.001). Both groups demonstrated comparable and acceptable surgical field scores in all subsequent readings. CONCLUSION: Nitroglycerin-induced deliberate hypotension was accompanied by higher peripheral perfusion index and lower serum lactate levels than labetalol-induced deliberate hypotension during sinus endoscopic surgery. TRIAL REGISTRATION: The study was registered at clinicaltrials registry system with trial number: NCT03809065. Registered at 19 January 2019. This study adheres to CONSORT guidelines.

Effectiveness and safety of hypotensive resuscitation in traumatic hemorrhagic shock: A protocol for meta-analysis.

BACKGROUND: Hypotensive resuscitation is an old study. But its benefits and losses are still controversial. In clinic, the method of fluid resuscitation needs more reliable experimental evidence. This study's objective is to systematically evaluate the efficacy of hypotensive resuscitation in patients with traumatic hemorrhagic shock. METHODS AND ANALYSIS: Through October 2019, Web of Science, PubMed, the Cochrane Library, EMBASE, and Clinical Trials will be systematically searched to identify randomized controlled trials exploring the efficacy of hypotensive resuscitation in traumatic hemorrhagic shock. Strict screening and quality evaluation will be independently performed on the obtained literature by 2 researchers; outcome indexes will be extracted, and a meta-analysis will be performed on the data using Revman 5.3 software. ETHICS AND DISSEMINATION: The stronger evidence about the efficacy of hypotensive resuscitation in traumatic hemorrhagic shock will be provided for clinicians. TRIAL REGISTRATION NUMBER: PROSPERO CRD42019133169. STRENGTHS OF THIS STUDY: This study is not only a simple combination of data, but also to verify and discuss the reliability of the results, and provide more convincing evidence for clinicians. LIMITATIONS OF THIS STUDY: Firstly, according to the previous literature researching, it is found that the number of relevant randomized controlled trials is small and the quality level of the literature is uneven. Secondly, the efficacy of hypotensive resuscitation is discussed for a long time, different trials may take place at different times. Comparability between different trials is reduced.

Comparison of the effect of propofol and desflurane on S-100ß and GFAP levels during controlled hypotension for functional endoscopic sinus surgery: A randomized controlled trial.

BACKGROUND: Although surgical field visualization is important in functional endoscopic sinus surgery (FESS), the complications associated with controlled hypotension for surgery should be considered. Intraoperative hypotension is associated with postoperative stroke, leading to subsequent hypoxia with potential neurologic injury. We investigated the effect of propofol and desflurane anesthesia on S-100ß and glial fibrillary acidic protein (GFAP) levels which are early biomarkers for cerebral ischemic change during controlled hypotension for FESS. METHODS: For controlled hypotension during FESS, anesthesia was maintained with propofol/remifentanil in propofol group (n = 30) and with desflurane/remifentanil in desflurane group (n = 30). For S-100ß and GFAP assay, blood samples were taken at base, 20 and 60 minutes after achieving the target range of mean arterial pressure, and at 60 minutes after surgery. RESULTS: The base levels of S-100ß were 98.04 ±â€Š78.57 and 112.61 ±â€Š66.38 pg/mL in the propofol and desflurane groups, respectively. The base levels of GFAP were 0.997 ±â€Š0.486 and 0.898 ±â€Š0.472 ng/mL in the propofol and desflurane groups, respectively. The S-100ß and GFAP levels were significantly increased in the study period compared to the base levels in both groups (P ≤ .001). There was no significant difference at each time point between the 2 groups. CONCLUSION: On comparing the effects of propofol and desflurane anesthesia for controlled hypotension on the levels of S-100ß and GFAP, we noted that there was no significant difference in S-100ß and GFAP levels between the 2 study groups. CLINICAL TRIAL REGISTRATION: Available at: http://cris.nih.go.kr, KCT0002698.

[TAVI simplification: A focus]. / Simplification des procédures TAVI : mise au point.

After a first procedure carried out in 2002 by Pr Cribier's, Transcatheter Aortic Valve Replacement or TAVR revolutionized the management of aortic stenosis with a constant increase in the number of procedures performed worldwide. Experience of operators and teams and evolution of the technique has been accompanied by a drastic reduction in complications in patients at lower surgical risk. In parallel, the procedure was considerably simplified, carried out more and more under local anesthesia, with percutaneous femoral approach, secondary radial approach, prosthesis implantation without predilatation, rapid pacing on left ventricle wire and early discharge. Thus, the "simplified" TAVR adopted in most centers nowadays is a real revolution of the technique. However, simplified TAVR must be accompanied upstream by a rigorous selection of patients who can benefit from a minimalist procedure in order to guarantee its safety.

Effects of the nontourniquet combined with controlled hypotension technique on pain and long-term prognosis in elderly patients after total knee arthroplasty: a randomized controlled study.

PURPOSE: The aim of this study was to confirm the alleviating effects of the nontourniquet technique on the postoperative acute and chronic pain of patients after total knee arthroplasty (TKA). METHODS: 122 elderly patients undergoing TKA were randomly divided into two groups: group T (n = 58) and group H (n = 64). An electronic inflatable tourniquet was used during TKA in group T. The patients in group H received controlled hypotension but without tourniquet use during the operation. The numeric rating scale (NRS) score was used to evaluate pain level on day 1, day 2, day 3 and day 7 after the operation, and the incidence of chronic pain was judged at 3-month and 1-year follow-ups, and functional recovery of the knee joint was estimated by the active range of knee joint motion (AROM) at the same time points. Cognitive function was assessed by the montreal cognitive assessment scale (MoCA) for 7 days after operation. RESULTS: There were no significant differences in the NRS scores and AROM for 7 days after surgery. The incidence rate of chronic pain in group H (25.0%) was lower than that in group T (41.4%) and the AROM in group H was greater at one year follow-up. The MoCA score in group H was lower than that in group T on day 1 and day 2. CONCLUSION: The nontourniquet combined with controlled hypotension technique can alleviate chronic pain and promote the long-term rehabilitation of patients after TKA.

Adenosine-induced transient hypotension for carotid artery injury during endoscopic skull-base surgery: case report and review of the literature.

BACKGROUND: As the management of ventral skull-base pathology has transitioned from open to endonasal treatment, there has been an increased focus on the prevention and endoscopic endonasal management of internal carotid artery (ICA) and major vascular injury. The use of adenosine to induce transient hypotension or flow arrest has been previously described during intracranial aneurysm surgery; however, there have been no reports of the technique being used during endonasal skull-base surgery to achieve hemostasis following major vascular injury. METHODS: Case report (n = 1) and literature review. RESULTS: A 25-year-old female underwent attempted endoscopic endonasal resection of an advanced right-sided chondrosarcoma. During resection of the tumor, brisk arterial bleeding was encountered consistent with focal injury to the right cavernous ICA. Stable vascular hemostasis could not be achieved with tamponade. An intravenous bolus dose of adenosine was administered to induce a transient decrease in systemic blood pressure and facilitate placement of the muscle patch over the direct site of vascular injury. The patient subsequently underwent endovascular deconstruction of the right ICA. CONCLUSION: This is the first reported use of adenosine to induce transient hypotension for a major vascular injury sustained during endonasal skull-base surgery. Based on well-established safety data from neurosurgical application, adenosine has the potential to be used as a safe and effective adjunctive technique in similar endonasal circumstances and may represent an additional tool in the armamentarium of the skull-base surgeon. Surgeons should consider having adenosine available when a risk of ICA injury is anticipated.

Changes of intraocular pressure and ocular perfusion pressure during controlled hypotension in patients undergoing arthroscopic shoulder surgery: A prospective, randomized, controlled study comparing propofol, and desflurane anesthesia.

PURPOSE: The aim of the present study is to evaluate the effects of deliberate hypotensive anesthesia on intraocular pressure (IOP) and ocular perfusion pressure (OPP) and compare the effects of propofol total intravenous anesthesia (TIVA) and desflurane anesthesia on IOP and OPP. METHODS: A total of 50 patients undergoing arthroscopic shoulder surgery in the lateral decubitus position were randomized to receive desflurane or propofol anesthesia. Mean arterial pressure (MAP) was maintained in the range of 60-75 mm Hg during hypotensive anesthesia. IOP was measured using a handheld tonometer at 7 time points: before induction (T1, baseline); immediately after endotracheal intubation (T2); 10 minutes after position change to lateral decubitus (T3); 10, 30, and 50 minutes after the start of hypotensive anesthesia (T4-T6); and at the end of surgery (T7). RESULTS: MAP decreased about 35% to 38% during hypotensive anesthesia. Compared to baseline values, the IOP at T6 in dependent and non-dependent eyes decreased by 0.43 and 2.74 mm Hg, respectively in desflurane group; 3.61 and 6.05 mm Hg, respectively in the propofol group. IOP of both eyes in the propofol group was significantly lower than in the desflurane group from T2 to T7. OPP of both eyes in both groups was significantly lower than at baseline, except at T2 in the desflurane group. OPP of both eyes in the propofol group was significantly higher than that in the desflurane group at T5 and T6. CONCLUSIONS: Hypotensive anesthesia reduced IOP and OPP, but propofol TIVA maintained higher OPP than desflurane anesthesia. These findings suggest that propofol TIVA can help mitigate the decrease of OPP during hypotensive anesthesia.

Damage Control Resuscitation in polytrauma patient. / Damage Control Resuscitation en el paciente traumático.

Haemorrhagic shock is one of the main causes of mortality in severe polytrauma patients. To increase the survival rates, a combined strategy of treatment known as Damage Control has been developed. The aims of this article are to analyse the actual concept of Damage Control Resuscitation and its three treatment levels, describe the best transfusion strategy, and approach the acute coagulopathy of the traumatic patient as an entity. The potential changes of this therapeutic strategy over the coming years are also described.

The Utility of Echocardiography for the Prediction of Spinal-Induced Hypotension in Elderly Patients: Inferior Vena Cava Assessment Is a Key Player.

OBJECTIVES: To prospectively assess the diagnostic performance of echocardiographic measurements before spinal anesthesia in elderly patients undergoing lower limb surgery. Emphasis was placed on the dIVCmax-to-IVCCI ratio and IVCCI, where dIVCmax was the maximum diameter of inferior vena cava (IVC) at expiration and IVCCI was the collapsibility index of IVC. DESIGN: Open cohort, prospective, single-center study. SETTING: University hospital. INTERVENTIONS: A transthoracic echocardiography examination was performed in 70 patients before spinal anesthesia under standard criteria and protocol. Patients with intraoperative mean arterial pressure ≤65 mmHg or ≥25% reduction of its preoperative baseline were considered hypotensive. MEASUREMENTS AND MAIN RESULTS: Preoperative echocardiographic measurements, including IVCCI, dIVCmax-to-IVCCI, ejection fraction, global longitudinal peak systolic strain, tricuspid annular plane systolic excursion, ratio of peak velocity flow in early diastole and average of peak velocities in early diastole of lateral and septal mitral annulus, stroke volume index, and left ventricle mass index were assessed. Twenty-eight of 70 patients manifested spinal-induced hypotension. Preoperative dIVCmax-to-IVCCI showed the greatest diagnostic performance among the indices. dIVCmax-to-IVCCI <43 had significantly higher diagnostic power than did IVCCI >0.3 (p = 0.032). Multiple logistic regression analysis revealed that the best predictors for spinal-induced hypotension were the dIVCmax-to-IVCCI ratio and age. CONCLUSIONS: The preoperative dIVCmax-to-IVCCI ratio can predict spinal-induced hypotension greater than IVCCI and other echocardiographic measurements in elderly patients. Both dIVCmax-to-IVCCI ratio and patient age can act as predictors of spinal-induced hypotension in elderly patients.

The beach chair position for shoulder surgery in intravenous general anesthesia and controlled hypotension: Impact on cerebral oxygenation, cerebral blood flow and neurobehavioral outcome.

STUDY OBJECTIVES: The aim of this study was to assess the impact of intravenous general anesthesia and controlled hypotension on cerebral saturation (rScO2), cerebral blood flow measured as middle cerebral artery blood flow velocity (Vmax MCA) and neurobehavioral outcome in patients scheduled for shoulder surgery in beach chair position. DESIGN: Prospective, assessor-blinded observational study. SETTING: University hospital, shoulder surgery operating room. PATIENTS: Forty ASA I-II patients scheduled for shoulder surgery in beach chair position and controlled hypotension. INTERVENTIONS: Neurological and neurobehavioral tests were performed prior and the day after surgery. The baseline data for near-infrared spectroscopy, bispectral index, cerebral blood flow, PaCO2 and invasive blood pressure (radial artery) were taken prior anesthesia and after anesthesia induction, after beach chair positioning and all 20 min after surgery start until discharge of the patient. MEASUREMENTS: Neurological and neurobehavioral tests, cerebral saturation (rScO2) using near-infrared spectroscopy, BIS, cerebral blood flow using Doppler of the middle cerebral artery (Vmax MCA), PaCO2 and invasive blood pressure assessed at heart and at the external acoustic meatus level. MAIN RESULTS: The incidence of cerebral desaturation events (CDEs) was 25%. The blood pressure drop 5 min after beach chair position measured at the acoustic meatus level in the CDE group was higher compared to patients without CDEs (p = 0.009) as was the rScO2 (p = 0.039) and the Vmax MCA (p = 0.002). There were no neurological deficits but patients with CDEs showed a greater negative impact on neurobehavioral tests 24 h after surgery compared to patients without CDEs (p = 0.001). CONCLUSIONS: In ASA I-II patients intravenous general anesthesia and controlled hypotension in the beach chair position affects cerebral blood flow and cerebral oxygenation with impact on the neurobehavioral outcome.

Controlled hypotension during middle ear surgery: hemodynamic effects of remifentanil vs nitroglycerin.

INTRODUCTION: Controlled hypotension is a well-known technique used by anesthesiologists to limit intraoperative bleeding in patients undergoing middle ear surgery and improve visibility of the surgical field. Nitroglycerin and remifentanil are among the drugs used to induce controlled hypotension.The aim of our study was to compare the hemodynamic effects of remifentanil and nitroglycerin in this patient population. METHODS: All consecutive patients who underwent middle ear surgery between January and December 2016, at the University Hospital Vittorio Emanuele in Catania were included in a retrospective study. Patients who were given nitroglycerin to induce controlled hypotension were compared to those given remifentanil. The following parameters were measured systolic and diastolic blood pressure, heart rate, peripheral (capillary) oxygen saturation, and fraction of expired carbon dioxide. A mean arterial pressure of 50-70 mmHg was considered optimal. RESULTS: Thirty patients who underwent stapedioplasty and tympanoplasty, 25 men and 5 women,with a mean age of 43 years (range 32-58 years) were included in the study. Fifteen patients had received nitroglycerin (group A) and 15 patients remifentanil (group B). The target blood pressure was reached in all patients and no significant difference was found between the groups with regard to the level of systolic and diastolic blood pressure, heart rate, peripheral (capillary) oxygen saturation, and fraction of expired carbon dioxide. However the heart rate of 2 younger patients in group A rose to > 100 bpm after the administration of nitroglycerin. CONCLUSION: Both remifentanil and nitroglycerin are effective in inducing controlled hypotension. In younger patients administration of nitroglycerin is associated with an increase in heart rate. KEY WORDS: Controlled hypotension, Middle ear surgery, Nitroglycerin, Remifentanil.

Rapid cardiac ventricular pacing to facilitate embolization of vein of Galen malformations: technical note.

In BriefBabies born with life-threatening brain blood-vessel malformations can be helped with new heart pacemaker technology to temporarily stop the flow of blood in their bodies during surgery, for inducing hypotension to aid in controlled embolization.

[Hemodynamic effects of cafedrine/theodrenaline on anesthesia-induced hypotension]. / Hämodynamisches Wirkungsspektrum von Cafedrin/Theodrenalin bei Anästhesie-assoziierter Hypotension.

BACKGROUND: There is insufficient knowledge about the hemodynamic effects of cafedrine/theodrenaline (caf/theo), a commercially available drug combination, to treat hypotension. METHODS: This prospective observational study investigated the hemodynamic effects of caf/theo on anesthesia-induced hypotension in 20 patients scheduled for elective major abdominal surgery. After induction of total intravenous anesthesia (TIVA) with propofol and remifentanil, a decrease in mean arterial blood pressure (MAP) below 60 mm Hg (n = 12) was treated with 60 mg/3 mg caf/theo. The systemic vascular resistance index (SVRI), cardiac index (CI), global end-diastolic index (GEDI), maximum pressure increase in the aorta (dPmx) and global ejection fraction (GEF) were assessed by transpulmonary thermodilution (PiCCO2-Monitor). RESULTS: The MAP increased by approximately 60% 10 min after administration of caf/theo. The increase in MAP was a result of the simultaneous effects on various cardiovascular determinants. An increase in peripheral resistance (SVRI +42%) and CI (+17%) could be determined. Data further indicated that the increase in CI was a consequence of an increase in both dPmx (+31%) and GEDI (+9%) but the GEF remained constant. CONCLUSION: In anesthesia-induced hypotension caf/theo effectively increased the mean arterial blood pressure by combined effects on preload, contractility, and afterload without altering cardiovascular efficiency.