Spinal anesthesia for elective lumbar spine surgery

Study Objective: To evaluate a large series of elective lumbar spine surgical procedures by a single surgeon whose patients were all offered spinal anesthesia.

Design: Retrospective chart review.

Setting: Tertiary-care teaching hospital.

Measurements and Main Results: The records of all elective lumbar spine procedures between 1984 and 1995 performed by one surgeon (GRB) were obtained, and 803 were identified. Of those 803 patients, 611 accepted spinal anesthesia. Data collected included patient demographics, details of the spinal and general anesthesia, perioperative complications, and impact of the spinal anesthetic options on the outcome of spinal anesthesia. General and spinal anesthesia patients were comparable for age, gender, height, and ASA physical status. Patients who received spinal anesthesia were significantly heavier than the general anesthesia patients. Among perioperative complications, nausea and deep venous thrombosis occurred significantly more often in the general than spinal anesthesia patients. Mild hypotension and decreased heart rate (HR) were the most common hemodynamic changes with spinal anesthesia, whereas hypertension and increased HR were the result of general anesthesia. Among spinal anesthetic drugs, plain bupivacaine was associated with the lowest incidence of supplemental local anesthetic use intraoperatively compared to hyperbaric bupivacaine or hyperbaric tetracaine.

Conclusion: Spinal anesthesia is an effective alternative to general anesthesia for lumbar spine surgery and has a reduced rate of minor complications.     

Multimodal strategies to improve surgical outcome

OBJECTIVE: To evaluate the effect of modifying perioperative care in noncardiac surgical patients on morbidity, mortality, and other outcome measures. BACKGROUND: New approaches in pain control, introduction of techniques that reduce the perioperative stress response, and the more frequent use of minimal invasive surgical access have been introduced over the past decade. The impact of these interventions, either alone or in combination, on perioperative outcome was evaluated.METHODS: We searched Medline for the period of 1980 to the present using the key terms fast track surgery, accelerated care programs, postoperative complications and preoperative patient preparation; and we examined and discussed the articles that were identified to include in this review. This information was supplemented with our own research on the mediators of the stress response in surgical patients, the use of epidural anesthesia in elective operations, and pilot studies of fast track surgical procedures using the multimodality approach. RESULTS: The introduction of newer approaches to perioperative care has reduced both morbidity and mortality in surgical patients. In the future, most elective operations will become day surgical procedures or require only 1 to 2 days of postoperative hospitalization. Reorganization of the perioperative team (anesthesiologists, surgeons, nurses, and physical therapists) will be essential to achieve successful fast track surgical programs. CONCLUSIONS: Understanding perioperative pathophysiology and implementation of care regimes to reduce the stress of an operation, will continue to accelerate rehabilitation associated with decreased hospitalization and increased satisfaction and safety after discharge. Developments and improvements of multimodal interventions within the context of "fast track" surgery programs represents the major challenge for the medical professionals working to achieve a "pain and risk free" perioperative course.     

全麻和颈丛阻滞行颈动脉内膜剥脱术的对比研究

目的比较全麻和颈丛阻滞行颈动脉内膜剥脱术(CEA)围术期血液动力学变化和并发症情况.方法64例颈动脉内膜剥脱术分别在全麻和颈丛阻滞下完成,每组32例.记录并计算两组围术期血液动力学参数的波动性,分流管使用率、心脑并发症,询问患者的满意程度和选择倾向.结果CEA全麻围术期的血液动力学波动性明显大于颈丛阻滞(P＜0.01),高血压和低血压的发生率也高于颈丛阻滞(P＜0.05);全麻分流管的使用率高于颈丛阻滞(P＜0.05),围术期心肌缺血的发生率也高于颈丛阻滞(P＜0.05),两组神经系统并发症无显著差异.患者对两种麻醉方法的满意程度无显著差异,倾向于选择已使用过的麻醉方法.结论全身麻醉和颈丛阻滞都可安全用于颈动脉内膜剥脱术,颈丛阻滞有利于维护围术期血液动力学的稳定,减少分流管的使用和心血管并发症.     

The role of a defined protocol for cardiac risk assessment in decreasing perioperative myocardial infarction in vascular surgery.

Major elective peripheral vascular surgery has historically carried a significant risk of perioperative myocardial infarction; this risk has been quantified further by its association with proved reduction in cardiac reserve/presence of coronary artery disease by stress testing or invasive monitoring. Recognition of this risk logically should lead to protocols that delineate coronary artery disease/cardiac reserve before surgery and correct for observed abnormalities during surgery. This study sought to show that a coherent algorithm of preoperative cardiac assessment combined with aggressive perioperative management could indeed reduce perioperative myocardial infarction rates. Six hundred thirty consecutive elective vascular operations were performed by the author during 6 years. All patients were entered into a prospective protocol for preoperative cardiac risk assessment, which then determined the choice of operation, type of anesthesia, and level of hemodynamic monitoring. Sixty-eight percent of the patients demonstrated clinical coronary artery disease, 15% had previously undergone coronary catheterization or surgery, and 9% had ejection fractions less than 35%. All patients underwent baseline detailed cardiac histories, radionuclide cardioangiography, and electrocardiograms. Patients with significant historic coronary artery disease or ejection fraction less than 50% underwent stress thallium testing; patients with positive fixed or redistribution defects then underwent catheterization, constituting 7% of the series. Risk stratification by age and cardiac assessment then dictated the perioperative care. The overall perioperative myocardial infarction rate was 0.7% (5/628), ranging from 0% for 156 aortic operations and 114 carotid endarterectomies to 0.6% for 159 femoropopliteal and 3.3% for 90 femorotibial revascularizations.(ABSTRACT TRUNCATED AT 250 WORDS)     

Perioperative blood glucose levels in children]

The perioperative blood glucose (BG) level may represent autonomic responses to various stresses by anesthesia and surgery. We studied the effects of regional blocks combined with general anesthesia on the BG response in pediatric patients. We could not find any significant differences in BG levels between blocked and non-blocked patients. However, BG levels of the children who had been hysterical or crying during the induction of anesthesia were significantly higher than those of the children who had been calm or sleeping. Forty healthy children, aged 1-3 yrs who were scheduled for elective urological surgery were studied. Anesthesia was induced with halothane in oxygen. The anesthesiologist recorded the children's attitude before and during the induction of anesthesia, and described as "calm or asleep (Calm-group), and hysterical or crying (Crying-group)". Patients were assigned randomly to two groups as follow; Group A (n = 20): receiving nerve blocks, Group B (n = 20): without the blocks. The anesthesia was maintained with 1-2.5% halothane in oxygen required to maintain the hemodynamic parameters within 10% of baseline value before surgery. Both groups received lactated-Ringer's solution during the study period. The venous BG levels were determined 5 times, i.e. immediately after asleep, 5, 15, 30 minutes after skin incision and at the conclusion of surgery. BG levels were compared between groups using Mann-Whitney Test. There was no significant difference in BG levels between Group A and B throughout the study period. But BG values of Crying-group (n = 9) were significantly higher than those of Calm-group (n = 31) during perioperative period.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemodynamic and catecholamine response to tracheal intubation: direct laryngoscopy compared with fiberoptic intubation

STUDY OBJECTIVE: To compare the stress response following tracheal intubation using direct laryngoscopy to that using fiberoptic bronchoscopy technique. DESIGN: Randomized, prospective study. SETTING: Operating rooms in a teaching hospital. PATIENTS: 51 ASA physical status I and II patients who were scheduled for an elective surgery with general anesthesia. INTERVENTIONS: Patients were randomly assigned to receive either direct laryngoscopy or fiberoptic orotracheal intubation, as part of general anesthesia. A uniform protocol of anesthetic medications was used. MEASUREMENTS: Blood pressure and heart rate were measured before induction, before endotracheal intubation, and 1, 2, 3, and 5 minutes afterwards. Catecholamine (epinephrine and norepinephrine) blood samples were drawn before the induction, and 1 and 5 minutes after intubation. MAIN RESULTS: Duration of intubation was shorter in the direct laryngoscopy group (16.9 (16.9 +/- 7.0 sec, range 8 to 40) compared with the fiberoptic intubation group (55.0 +/- 22.5 sec, range 29 to 120), p < 0.0,001. In both groups, blood pressure and heart rate were significantly increased at 1, 2, and 3 minutes after intubation, but there was no significant difference between the two study groups. Catecholamine levels did not increase after intubation and did not correlate with the hemodynamic changes. CONCLUSIONS: The use of either direct laryngoscopy or fiberoptic bronchoscopy produces a comparable stress response to tracheal intubation. Catecholamine levels do not correlate with the hemodynamic changes.     

Hormonal stress response and hemodynamic stability in patients undergoing endovascular vs. conventional abdominal aortic aneurysm repair.

BACKGROUND AND AIMS: To investigate the effect of two different surgical techniques with different anesthetic modes on intraoperative and postoperative hormonal stress response, hemodynamic stability, fluid loading and renal function in patients scheduled for elective infrarenal abdominal aortic aneurysm (AAA) repair. MATERIALS AND METHODS: Forty consecutive patients scheduled for elective infrarenal AAA repair were allocated without randomizing into two groups: an endovascular (EVAR, n = 20) and a conventional (CAR, n = 20) aneurysm repair group according to aneurysm morphology as determined by preoperative computed tomography and angiography. The EVAR group were operated under spinal anesthesia and the CAR group using general anesthesia with epidural blockade. RESULTS: Patients undergoing CAR showed lower intraoperative mean arterial pressure and significantly higher plasma norepinephrine before aortic cross-clamping and significantly higher lactate after aortic declamping and postoperatively than patients in the EVAR group. Postoperatively, vasopressin and serum cortisol were also significantly higher in the CAR group. Fluid loading and estimated blood loss were more excessive in the CAR group. CONCLUSIONS: Stress response was lower and hemodynamic stability and lower body perfusion superior and renal function also better maintained in patients undergoing EVAR under spinal anesthesia as compared to those undergoing CAR using general anesthesia with epidural blockade.     

Changes in cardio-pulmonary function during laparoscopic colectomy and postoperative quality of life--comparison with laparotomy

BACKGROUND: We investigated whether laparoscopic colectomy would affect the degree of respiratory and circulatory changes during surgery and could improve postoperative quality of life (QOL) as compared with laparotomy. METHODS: Fifty-one patients (ASA 1-3) scheduled for elective colectomy under general anesthesia with epidural anesthesia were enrolled in the study. All patients were divided into two groups (laparoscopic group: n = 33 and laparotomy group: n = 18) by surgical indication. Respiratory functions and hemodynamic changes were measured during surgery. Postoperative complications, pain scores, the time to start of walking and the period of hospital stay were examined. The serum concentrations of inflammatory cytokines (IL-6, IL-1 ra) and KL-6 were measured perioperatively. RESULTS: It was demonstrated that pneumoperitoneum and postural tilt had a bad influence on respiratory functions especially on pulmonary compliance and a-ET(D)co2 in laparoscopic group. The serum concentrations of inflammatory cytokines were significantly lower and the number of rescue for postoperative pain were less in laparoscopic group. The patients in laparoscopic group could begin to walk and leave hospital earlier after surgery. CONCLUSIONS: Severe complication did not occurr in both groups during the perioperative period. Laparoscopic surgery could improve postoperative QOL.     

A comparison of desflurane and isoflurane in patients undergoing coronary artery surgery

Animal studies indicate that desflurane and isoflurane have similar hemodynamic effects when administered in equipotent anesthetic concentrations. The authors compared desflurane and isoflurane, used as primary anesthetics for patients undergoing elective coronary artery bypass surgery whose left ventricular ejection fractions were greater than 0.34. After induction of anesthesia with thiopental (dose 180 +/- 45 mg [mean +/- standard deviation]) and fentanyl, 10 micrograms.kg-1, either desflurane or isoflurane was administered to maintain systolic blood pressure within 70-120% of, and heart rates less than 120% of, the patients' average preoperative values. If adjusting the end-tidal anesthetic concentration within the range of 0-2.0 MAC could not maintain these predefined hemodynamic limits, additional fentanyl or vasoactive drugs were used. Induction and maintenance of anesthesia was accompanied by a significant decrease in mean arterial pressure in both groups (desflurane 97 +/- 12 mmHg at control, decreasing to 71 +/- 5 mmHg during skin preparation; isoflurane 95 +/- 9 mmHg at control, 74 +/- 9 mmHg during skin preparation). One minute after sternotomy, mean arterial pressure in the isoflurane group had returned to control, 97 +/- 9 mmHg, which was significantly greater than in the desflurane group, 87 +/- 12 mmHg. Systolic arterial pressure was also significantly greater in the isoflurane group 1 min after intubation, during skin preparation, and 1 min after sternotomy. Otherwise, the hemodynamic effects of these volatile agents were similar. There were no differences between groups in the incidence of ECG changes indicative of myocardial ischemia prior to cardiopulmonary bypass, perioperative myocardial infarction, or perioperative mortality.(ABSTRACT TRUNCATED AT 250 WORDS)     

Importance of relative pulmonary hypertension in cardiac surgery: the mean systemic-to-pulmonary artery pressure ratio

OBJECTIVE: To determine the importance of the mean arterial pressure-to-mean pulmonary artery pressure ratio (MAP/MPAP) in cardiac surgical patients. DESIGN: Retrospective and prospective studies (3 groups). SETTING: Tertiary care hospital. PARTICIPANTS: Cardiac surgical patients (1,557). INTERVENTION: Retrospective analysis (group 1), induction of general anesthesia (group 2), and transesophageal Doppler echocardiography (group 3). MEASUREMENTS AND MAIN RESULTS: In group 1 (n = 1,439), demographic, hemodynamic, and other perioperative variables were collected with follow-up until hospital discharge. The primary outcome was a composite index of hemodynamic complications that included death, resuscitated cardiac arrest, use of vasopressive drugs for >24 hours postoperatively, or the use of an intra-aortic balloon pump that was not present preoperatively. In group 2 (n = 34), the effect of general anesthesia on the MAP/MPAP ratio was studied, and Doppler echocardiography was used to evaluate diastolic profiles in group 3 (n = 74). In group 1, a total of 302 patients experienced hemodynamic complications (21%). The MAP/MPAP ratio was significantly lower in the patients who developed complications (3.3 +/- 1.3 v 4.0 +/- 1.4, p < 0.0001). Multiple stepwise logistic regression analysis showed the MAP/MPAP ratio to be an independent predictor of hemodynamic complications (p < 0.0001). In group 2, the induction of anesthesia decreased both MAP and MPAP, but the ratio remain unchanged (p = 0.242). In group 3, patients with moderate-to-severe diastolic dysfunction (DD) had a lower ratio (3.5 +/- 0.9 v 4.0 +/- 1.1 compared with those with normal-to-mild DD, p = 0.07). CONCLUSION: The MAP/MPAP ratio is a useful hemodynamic variable in cardiac surgery. It can be used to predict hemodynamic complications after cardiac surgery, is not influenced by the induction of anesthesia, and tends to correlate with the severity of left ventricular diastolic profiles.     

Ineffectiveness of arterial pressure measurement and cardiac rate in detecting hypoxemia in the postanesthetic period]

The purpose of the study was to analyze the hemodynamic response to hypoxemia induced during the first postoperative hour. We studied 151 patients who underwent general anesthesia for elective surgery. Arterial saturation of oxyhemoglobin (SpO2), heart rate (HR), and systolic arterial pressure (SAP) during respiration with atmospheric air were measured 20 min and 80 min after admission at the recovery room. We compared HR and SAP between hypoxemic (SpO2 less than or equal to 90%) and non-hypoxemic patients (SpO2 greater than 90%) and we did not find significant differences. SpO2 failed to correlate with HR or with SAP in any of the time samples. This lack of correlation was also observed between patients with or without halogenated anesthetic treatment. Our results indicate that the possible inhibitory effect of anesthesia on hemodynamic response to hypoxemia lasts at least during the first postoperative hour and it does not depend on the administration of halogenated anesthetics. We also conclude that postoperative hemodynamic stability is not an accurate index of the status of arterial oxygenation.     

The use of epidural anesthesia and analgesia in aortic surgery.

During a 3-year period, sixty-four consecutive patients, who had elective aortic reconstruction were investigated to determine whether epidural anesthesia and analgesia, combined with light general anesthesia, would lower the rate of perioperative complications in this high-risk group of patients. The epidural group comprised 32 consecutive patients who had surgery during the 20-month period from July 1986 to December 1987. These patients were compared with the previous 32 patients who had aortic reconstruction at Huntington Memorial Hospital (Pasadena, CA) using conventional general anesthetic techniques. Cardiovascular and respiratory morbidity, length of hospital stay, length of intensive care unit stay, and duration of endotracheal intubation were compared. There was no statistically significant difference in cardiovascular morbidity, length of hospital stay, or intensive care unit stay between the two groups. There was however, a striking decrease in respiratory complications and length of intubation in the epidural anesthesia group (P less than 0.005). The authors conclude that epidural anesthesia and analgesia, combined with a light general anesthetic may confer benefits over conventional general anesthesia in patients undergoing aortic surgery.     

Efeitos do bloqueio peridural caudal em pacientes cirúrgicos pediátricos: estudo randomizado

BackgroundSurgery generates a neuroendocrine stress response, resulting in undesirable hemodynamic instability, alterations in metabolic response and malfunctioning of the immune system.ObjectivesThe aim of this research was to determine the effectiveness of caudal blocks in intra‐ and postoperative pain management and in reducing the stress response in children during the same periods.MethodsThis prospective, randomized clinical trial included 60 patients scheduled for elective herniorrhaphy. One group (n = 30) received general anesthesia and the other (n = 30) received general anesthesia with a caudal block. Hemodynamic parameters, drug consumption and pain intensity were measured. Blood samples for serum glucose and cortisol level were taken before anesthesia induction and after awakening the patient.ResultsChildren who received a caudal block had significantly lower serum glucose (p < 0.01), cortisol concentrations (p < 0.01) and pain scores 3 hours (p = 0.002) and 6 hours (p = 0.003) after the operation, greater hemodynamic stability and lower drug consumption. Also, there were no side effects or complications identified in that group.ConclusionsThe combination of caudal block with general anesthesia is a safe method that leads to less stress, greater hemodynamic stability, lower pain scores and lower consumption of medication.     

The effect of clonidine on perioperative blood coagulation

STUDY OBJECTIVE: To evaluate the influence of perioperative stress protection by clonidine on blood coagulation. DESIGN: Prospective, randomized, double-blinded, placebo-controlled clinical trial. SETTING: University hospital. PATIENTS: 50 patients scheduled for elective gynecoabdominal surgery. INTERVENTIONS AND MEASUREMENTS: Patients were randomly assigned to control (placebo) or clonidine group (single intravenous clonidine dose; 4 microg/kg(-1) or 3 microg/kg(-1) for age >65 years). Three measurement time points were defined: before administration of placebo/clonidine and anesthesia induction, (t1; baseline measurement); after surgery, before emergence of anesthesia (t2); and at the first postoperative day, 24 hours after anesthesia induction (t3). Blood coagulation was analyzed at all time points measuring international normalized ratio, platelets, thrombin-antithrombin complex, von Willebrand factor, soluble thrombomodulin, d-dimers, plasminogen activator inhibitor 1, and Thrombelastograph analysis. MAIN RESULTS: In the postoperative period (t2, t3), hypercoagulability was present in all patients compared with baseline measurements (t1) but without differences between the control and clonidine group. Regarding hematologic, laboratory blood coagulation, and Thrombelastograph parameters, there was no statistically and clinically relevant difference throughout the study period between the 2 groups. No hemodynamic adverse events of clonidine were observed in the perioperative period. Until day of discharge, no thrombotic or thromboembolic events were reported in both groups. CONCLUSIONS: Preoperative administration of a single dose of clonidine has no effect on perioperative blood coagulation.     

Perioperative Cost-finding Analysis of the Routine Use of Intraoperative Forced-air Warming during General Anesthesia

Background: Despite the well-documented ability of forced-air warming (FAW) to maintain normothermia, it is unclear whether this technique results in a net increase or decrease in costs. The authors did a prospective cost-finding study comparing FAW with routine thermal care in patients at low risk for perioperative complications who were undergoing general anesthesia.

Methods: After institutional review board approval was received, 100 patients were studied who were having elective surgery scheduled for more than 2 h during general endotracheal anesthesia. Patients were randomly assigned to one of two groups: FAW or routine thermal care. All patients received a standardized anesthetic. Anesthesia providers were blinded to core temperatures and the use of FAW. Primary outcomes were those associated with perioperative costs.

Results: The time from completion of surgical dressing until tracheal extubation was significantly reduced in the FAW group (10 +/- 1 min compared with 14 +/- 1 min; mean +/- SEM; P < 0.01). There was no demonstrable difference in attainment of postanesthesia care unit discharge criteria between the two groups, although the FAW group used one less cotton blanket there. The net savings related to the use of the FAW depends on the percentage of the intraoperative costs that are fixed rather than variable ($15 additional for FAW if all costs are fixed compared with $29 savings if all costs were variable).     

Hemodynamics and emergence profile of remifentanil versus fentanyl prospectively compared in a large population of surgical patients

STUDY OBJECTIVE: To compare the responses to, and hemodynamics associated with surgical stress, recovery profiles, and anesthesiologists' satisfaction following balanced general anesthesia using either remifentanil or fentanyl in a large-scale population. DESIGN: Prospective, 1:1 single blind, randomized, controlled effectiveness study in which patients received either remifentanil or fentanyl in combination with a hypnotic-based anesthesia regimen of either isoflurane or propofol. SETTING: Multicenter study including 156 hospitals and ambulatory surgery facilities. PATIENTS: 2,438 patients (1,496 outpatients and 942 inpatients), 18 years of age or older, scheduled for elective surgeries under general endotracheal anesthesia, with an expected duration of unconsciousness > or =30 minutes. INTERVENTIONS: Patients were randomized to receive either intravenous (IV) remifentanil (0.5 microg/kg/min for induction and intubation, with the infusion rate decreased to 0.25 microg/kg/min after intubation) or IV fentanyl (administered according to anesthesiologists' usual practice) as the opioid during surgery. Concomitant hypnotic drugs were either propofol and/or isoflurane (with or without nitrous oxide) titrated according to protocol. Transition analgesia with either morphine or fentanyl was given to the remifentanil patients and, at the anesthesiologists' discretion, in the fentanyl patients. MEASUREMENTS: Vital signs, adverse events, and emergence profiles were assessed and recorded. Recovery profile was assessed by recording time spent in the postanesthesia care unit and step-down recovery unit, number and timing of adverse events, timing and dosage of rescue medications, and time to eligibility for discharge (to home or to hospital room). Anesthesiologists' satisfaction with the anesthetic regimen was assessed at the end of surgery. MAIN RESULTS: Remifentanil-treated patients exhibited lower systolic and diastolic blood pressures (by 10-15 mmHg) and lower heart rates (by 10-15 bpm) intraoperatively compared to the fentanyl-treated patients. This difference promptly disappeared on emergence. Remifentanil-treated patients responded to verbal command, left the operating room, and (for outpatients) were discharged home sooner than fentanyl-treated patients. Anesthesiologists rated the predictability of response to intraoperative titration, assessment of hemodynamic profiles, and the quality of anesthesia higher in the remifentanil-treated patients. CONCLUSIONS: This study confirms previous observations on the hemodynamic properties associated with remifentanil and extends these to a wider context than previously reported. These characteristics provide clinicians with an alternative in opioid-based anesthesia.     

Assessing pediatric anesthesia practices for volunteer medical services abroad.

BACKGROUND: Anesthetic techniques and problems in volunteer medical services abroad are different from those of either the developed countries from which volunteers originate or the host country in which they serve because of differences in patient population, facilities, and goals for elective surgery. Assessing outcomes is hampered by the transience of medical teams and the global dispersion of providers. We studied general anesthesia techniques and outcomes in a large international voluntary surgical program. METHODS: Anesthesia providers and nurses participating in care of patients undergoing reconstructive plastic and orthopedic surgery by Operation Smile over an 18-month period were asked to complete a quality assurance data record for each case. Incomplete data were supplemented by reviewing the original patient records. RESULTS: General anesthesia was used in 87.1% of the 6,037 cases reviewed. The median age was 5 yr (25th-75th percentiles: 2-9 yr). Orofacial clefts accounted for more than 80% of procedures. Halothane mask induction was performed in 85.6% of patients; 96.3% of patients had tracheal intubation, which was facilitated with a muscle relaxant in 19.3%. Respiratory complications occurred during anesthesia in 5.0% of patients and during recovery (postanesthesia care unit) in 3.3%. Arrhythmias requiring therapy occurred in 1.5%, including three patients to whom cardiopulmonary resuscitation was administered. Prolonged ventilatory support was required in seven patients. There was one death. Inadvertent extubation during surgery occurred in 38 patients. Cancellation of surgery after induction of anesthesia occurred in 25 patients. Overall, complications were more common in younger children. CONCLUSIONS: Our study showed that in this setting it is feasible to track anesthesia practice patterns and adverse perioperative events. We identified issues for further examination.     

Lessons learned from anesthetic management of pheochromocytoma resection: a report of three cases

The anesthetic management of patients with pheochromocytoma, in which drastic hemodynamic changes may occur, is still a challenge to even the most experienced anesthesiologist, although the perioperative mortality has been reduced remarkably. We report three patients who developed unexpected major complications during elective resection of a pheochromocytoma. The Case 1 patient was a 46 year-old woman who developed ventricular tachycardia immediately after administration of ephedrine for transient hypotension induced by excessive phentolamine. Even a mild beta adrenergic agent may cause extraordinary stimulation to myocardium under alpha blockade. The Case 2 patient was a 44 year-old man who needed intensive vasodilating therapy due to an exaggerated cardiovascular response to intraoperative surgical stress. He developed severe metabolic acidosis resembling hyperdynamic shock before resection of the tumor, although blood pressure was controlled within the expected range. The Case 3 patient was a 60 year-old woman who did not receive preoperative alpha blocker therapy because she lacked cardiovascular symptoms. However, she revealed a high level of systemic vascular resistance after induction of general anesthesia and needed moderate inotropic support to compensate for an abrupt reduction of vascular resistance after resection of the tumor. The pathophysiology of the disease is complex and anesthetic care must be tailored in accordance with each patient's situation.     

Anesthetic management and outcomes for patients with pulmonary hypertension and intracardiac shunts and Eisenmenger syndrome: a review of institutional experience

Study ObjectiveTo propose a set of recommendations for the perioperative management of patients with Eisenmenger syndrome and similar physiology, based on 20 years of experience at a single institution.DesignRetrospective study of institutional outcomes of Eisenmenger syndrome patients and patients with balanced or fixed right-to-left intracardiac shunts with pulmonary hypertension undergoing noncardiac surgery.SettingSingle center, university-affiliated hospital.MeasurementsMeasurements included data from patients with Eisenmenger syndrome or similar physiology, shunt direction, right ventricular systolic pressure, congestive heart failure classification, noncardiac surgery, type of anesthesia, echocardiographic and catheterization data, mortality within 30 days of surgery, choice of monitoring, and vasopressor use.Main Results33 patients with Eisenmenger syndrome or similar physiology undergoing 53 general, regional and/or monitored anesthetic procedures were identified. Significant systemic arterial hypotension occurred in 14 individuals (26%) and oxygen desaturation in 9 (17%) patients. Administration of an intravenous (IV) vasopressor agent during induction significantly decreased the incidence of hypotension. The type of IV induction agent did not influence hemodynamic alterations, though patients who received propofol experienced a trend towards increased hypotension (83% of pts) when a vasopressor was not used. Inhalational induction, regardless of vasopressor use, was more likely to result in hypotension (60% of pts). The 30-day mortality was 3.8% (two pts). Both patients had minor elective procedures with monitored anesthesia care (MAC).ConclusionsHypotension is more common in patients with Eisenmenger syndrome and similar physiology when a vasopressor is not used during the peri-induction period, regardless of induction agent. Etomidate tended to have better hemodynamic stability than other induction agents. The use of a vasopressor is recommended. We present general recommendations for anesthesiologists and strongly recommend use of a vasopressor before or during induction to reduce hypotension along with complete avoidance of inhalational induction. Further, MAC anesthesia has been associated with perioperative and 30-day mortality.     

Changes in respiratory and hemodynamic parameters during low-dose propofol sedation in combination with regional anesthesia for herniorrhaphy and genitourinary surgery in children

BACKGROUND: Spontaneous vs mechanical ventilation during propofol sedation has been a subject of debate. We evaluated the safety of low-dose propofol sedation as an adjunct to regional anesthesia during herniorrhaphy and genitourinary surgery in infants and children. METHODS: The study was conducted in a prospective, nonrandomized manner using a consecutive sample of 62 American Society of Anesthesiologists physical status class I patients between 5 months to 11 years of age in the surgery unit of an urban University Hospital. Propofol sedation (4-8 mg x kg(-1) x h(-1) continuous infusion) was used with regional anesthesia (caudal, ilioinguinal/iliohypogastric nerve or penile block with 0.2-0.375% ropivacaine). All children were spontaneously breathing without an anesthesia circuit. Respiratory and hemodynamic parameters were continuously recorded on all patients. One-way analysis of variance (ANOVA) for repeated measurements was used to analyze changes in respiratory and hemodynamic parameters during the procedure. RESULTS: Spontaneous ventilation was maintained in all patients with minimal changes in hemodynamic parameters. Heart rate, mean arterial pressure, and P(E)CO(2) remained stable throughout the study period: 23/62 (37%) patients exhibited signs of developing intrinsic endexpiratory pressure (PEEPi) or the presence of PEEPi because of progressive reduction of expiratory time. CONCLUSIONS: Low-dose propofol sedation in combination with regional anesthesia for elective herniorrhaphy and genitourinary surgery in children maintains spontaneous ventilation and has minimal effects on hemodynamic parameters for sedation lasting <1 h. The presence of PEEPi is a relative contraindication to the use of this regimen in children with asthma or history of upper airway infections.