Biomedical subjects

W Scott Jellish

Publications and source records attributed to W Scott Jellish.

11 recordsLinked to original sources

PubMed2006

Effect of prone positioning systems on hemodynamic and cardiac function during lumbar spine surgery: an echocardiographic study.

STUDY DESIGN: Prospective randomized study of patients undergoing spine surgery. OBJECTIVE: To compare changes in hemodynamic and cardiac function after prone positioning using different prone positioners. SUMMARY OF BACKGROUND DATA: Prone positioning decreases blood pressure and cardiac function. Several studies have evaluated changes in cardiac function after prone positioning, and linked them to reduced venous return and ventricular compliance. This study compares different prone positioners using transesophageal echocardiography, and determines their effect on cardiac function and hemodynamics. METHODS: After correction of fluid deficits with the patient under stable anesthesia, hemodynamic and cardiac performance was measured using transesophageal echocardiography. After prone positioning, repeat measurements were performed, and comparisons were made between prone and supine positions. RESULTS: No intergroup differences in demographics, fluid deficit, baseline hemodynamics, or differences from supine to prone position were noted. Cardiac output decreased with the Wilson (Union City, CA) and Siemens AG (Munich, Germany) frames, while cardiac index and stroke volume decreased with the Andrews (Hollywood, CA), Wilson, and Siemens systems. Cardiac preload decreased using the Andrews frame. The Jackson spine table (Hollywood, CA) and bolsters had the least effect on cardiac performance. CONCLUSION: Adequate fluid replacement reduced hypotension and hemodynamic instability after prone positioning. The Jackson spine table and longitudinal bolsters had minimal effects on cardiac function, and should be considered in patients with limited cardiac reserve.

Adult↗

PubMed2006

Anesthetic issues and perioperative blood pressure management in patients who have cerebrovascular diseases undergoing surgical procedures.

Patients who have cerebrovascular disease and vascular insufficiency routinely have neurosurgical and nonneurosurgical procedures. Anesthetic priorities must provide a still bloodless operative field while maintaining cardiovascular stability and renal function. Patients who have symptoms or a history of cerebrovascular disease are at increased risk for stroke, cerebral hypoperfusion, and cerebral anoxia. Type of surgery and cardiovascular status are key concerns when considering neuroprotective strategies. Optimization of current condition is important for a good outcome; risks must be weighed against perceived benefits in protecting neurons. Anesthetic use and physiologic manipulations can reduce neurologic injury and assure safe and effective surgical care when cerebral hypoperfusion is a real and significant risk.

Anesthetics↗

PubMed2006

Long-term results with operated sinus tympani retraction cholesteatoma.

OBJECTIVES: Utilizing an endaural approach, we described the surgical treatment of 29 cases of sinus tympani retraction cholesteatoma in 1996. The purpose of this paper is to provide long-term results in this group of patients. STUDY DESIGN AND SETTING: A retrospective chart analysis of 29 previously reported patients was undertaken in an effort to identify hearing results and the risk of cholesteatoma recurrence following sinus tympani retraction surgery. RESULTS: The follow-up period ranged from 9 to 16 years (mean of 13.2 years). Speech discrimination (SD) and conductive hearing (CH) decline occurred in 23 of 28 patients, but only on the average of 5.6% and 9 dB throughout the speech frequencies, respectively. Speech discrimination and conductive hearing improved in 5 of 28 patients; one patient was lost to follow-up. One patient developed a recurrent cholesteatoma requiring a canal wall-down mastoidectomy. CONCLUSIONS: The endaural approach for sinus tympani cholesteatoma provided stable hearing in most of the patients in this series. One cholesteatoma recurrence required conversion to a canal wall-down mastoidectomy. This developed in a noncompliant patient, whose pars tensa retraction deepened as a result of failure to have his ventilation tube replaced. Semiannual office visits are recommended in patients who undergo this otologic approach for sinus tympani cholesteatoma.

Adolescent↗

PubMed2006

Morphine/ondansetron PCA for postoperative pain, nausea, and vomiting after skull base surgery.

OBJECTIVE: Patients who underwent skull base procedures have been noted to experience appreciable pain. This study examines pain after surgery and the effectiveness of patient controlled analgesia (PCA) with combination morphine ondansetron for analgesia and control of emesis. STUDY DESIGN AND SETTING: A total of 120 skull base surgery patients were randomized to receive placebo, morphine, or morphine ondansetron. Demographic and intraoperative variables were recorded along with pain, nausea, vomiting, and rescue analgesics. Total PCA use, hospital stay, satisfaction, and cost were also compared. RESULTS: Demographically the groups were similar. Pain was elevated with placebo PCA, and this group averaged twice as many analgesic rescues. Total usage time was lower with placebo PCA. Morphine ondansetron PCA had the lowest pain score with highest satisfaction. Nausea and vomiting was similar but female patients had more vomiting regardless of PCA group. CONCLUSIONS AND SIGNIFICANCE: The use of morphine PCA reduced pain and did not appreciably increase nausea or vomiting. The addition of ondansetron produced no real benefit and its PCA use cannot be justified. EBM RATING: A-1b.

Adolescent↗

PubMed2005

The effect of clonidine on cell survival, glutamate, and aspartate release in normo- and hyperglycemic rats after near complete forebrain ischemia.

The present study was undertaken to investigate the effects of the alpha2 adrenergic agonist, clonidine, on the near complete cerebral ischemia (NCFI) evoked release of glutamate and aspartate from normo- and hyperglycemic rodent brain tissue using microdialysis tissue techniques. Hemodynamic variables, blood lactate, and glucose levels were monitored throughout the 40 min NCFI occlusion period. After 48 h, rats were killed and the extent of neuronal injury was determined in the cortex, striatum, and hippocampus. Hemodynamic variables recorded during ischemia improved with clonidine treatment in both normo- and hyperglycemic groups. Glutamate and aspartate levels were greatly increased over control values during normo- and hyperglycemic NCFI treatment. Clonidine pretreatment suppressed the release of both glutamate and aspartate during NCFI in normo- and hyperglycemic rodents when compared with NCFI-treated normo- and hyperglycemic rats without the drug. Significant neuroprotection of cells in the cortex, striatum, and hippocampus was also observed in drug-treated animals 48 h postischemia. The combined effects of diminished glutamate release after NCFI and reduced neuronal injury in both normo- and hyperglycemic states suggests that clonidine treatment during NCFI is neuroprotective. The neuroprotective effect of clonidine during ischemia may be ascribed to both a sensitization of central sympathetic activity and a reduced release of glutamate thereby reducing NMDA receptor activation and neuronal damage.

Adrenergic alpha-Agonists↗

PubMed2005

Standard anesthetic technique for middle ear surgical procedures: a comparison of desflurane and sevoflurane.

OBJECTIVE: This study was designed to compare desflurane and sevoflurane anesthesia for middle ear microsurgery. STUDY DESIGN: One hundred healthy adults undergoing middle ear surgery were assigned to receive either desflurane or sevoflurane as their anesthetic. Intraoperative hemodynamics and BIS numbers were recorded. Hemodynamics, pain, nausea/vomiting, discharge readiness, and other parameters were compared postoperatively and 24 hours later. RESULTS: No intraoperative differences were noted except in BIS scores which trended lower with desflurane. PACU blood pressures were higher after desflurane but pain scores, nausea/vomiting, rescue anti-emetics, recovery scores, and discharge times were similar. A significant difference was noted in anesthetic costs (desflurane > sevoflurane), and in patients with the lowest BIS scores associated with more nausea/vomiting. CONCLUSIONS: Both anesthetics may be used for ototic surgery but propofol anesthesia should still be considered in patients with a history of emetic sequelae. SIGNIFICANCE: Short-acting inhalational anesthetics produce excellent operating conditions and reduce costs for otologic surgery.

Adult↗

PubMed2005

Effect of metoclopramide on gastric fluid volumes in diabetic patients who have fasted before elective surgery.

BACKGROUND: Diabetes-induced gastroparesis is believed to increase fasting gastric fluid volume before elective surgery. Metoclopramide is routinely administered preoperatively to reduce gastric fluid volume in these patients. This study compared nondiabetic controls to non-insulin-dependent and insulin-dependent diabetics to determine the effect of metoclopramide, administered before surgery, on gastric volumes in patients who fasted before surgery. METHODS: Control and diabetic patients fasted preoperatively before receiving either placebo or 10 mg intravenous metoclopramide 20 min before induction of anesthesia. After intubation, a gastric tube was placed, and stomach contents were aspirated with volumes compared among the groups. RESULTS: Both groups of diabetic patients were older than the control group, and insulin-dependent patients had a higher incidence of comorbidities compared with the non-insulin-dependent group. Fasting blood sugar and hemoglobin A1C values were higher in both insulin-dependent and non-insulin-dependent patients. Gastric fluid volumes were similar in control, non-insulin-dependent, and insulin-dependent patients (8.0 +/- 2.6 vs. 9.6 +/- 4.1 vs. 17.7 +/- 2.5 ml, respectively). In insulin-dependent diabetic patients, metoclopramide decreased gastric volume compared with placebo treatment (17.7 +/- 2.5 vs. 7.8 +/- 2.9 ml; P = 0.027). After stratification, a subpopulation of patients with poorly controlled diabetes, regardless of type, were identified to have increased gastric residual volumes. CONCLUSION: In elective surgical patients who have fasted before surgery, gastric volumes are minimal, even in diabetics with severe neuropathic symptoms. Metoclopramide prophylaxis to reduce gastric volumes seems to be unnecessary unless the patient has a prolonged history of poor blood glucose control.

Aged↗

PubMed2003

Spinal anaesthesia for spinal surgery.

Spinal anaesthesia for spinal surgery is becoming increasingly more popular because this anaesthetic technique allows the patient to self-position and avoid neurological injury that may occur with prone positioning under general anaesthesia. Spinal anaesthesia reduces intraoperative surgical blood loss, improves perioperative haemodynamic stability and reduces pain in the immediate postoperative period. This leads to a reduced need for analgesics and a reduction in the incidence of nausea and vomiting in the postoperative setting. Spinal anaesthesia for lumbar spine surgery also decreases the incidence of lower extremity thrombo-embolic complications and does not increase the occurrence of problems with micturition. These benefits increase the patient's satisfaction, and they expedite discharge of the patient from the hospital. Combination anaesthetic techniques, using both subarachnoid and epidural dosing schemes, may be beneficial for improving postoperative pain control and add further to the benefit of spinal anaesthesia for lumbar spine surgical procedures.

Anesthesia, Spinal↗

PubMed2003

Hemodynamic stability, myocardial ischemia, and perioperative outcome after carotid surgery with remifentanil/propofol or isoflurane/fentanyl anesthesia.

This study compares remifentanil/propofol (remi/prop) with isoflurane/fentanyl (iso/fen) anesthesia to determine which provides the greater hemodynamic stability, lesser myocardial ischemia, and morbidity with better postoperative outcomes after carotid endarterectomy. Sixty patients undergoing unilateral carotid endarterectomy were randomized to receive either a remi/prop or iso/fen anesthetic. Hemodynamic variables were recorded during the surgical procedure. In addition, transesophageal echocardiography was used to assess evidence of intraoperative regional wall motion abnormalities suggestive of cardiac ischemia. Emergence and extubation times, recovery from anesthesia, hemodynamic instability, nausea, vomiting, and pain in post anesthesia recovery, discharge delays, ICU admittance, hospital discharge, and preoperative and postoperative troponin levels were compared using appropriate statistical methods with P < 0.05 considered significant. The groups were demographically alike. Hemodynamic variables were similar during intubation and throughout surgery. Twenty-two percent of patients receiving iso/fen developed intraoperative regional wall motion abnormalities suggestive of ischemia, whereas no remi/prop patients had changes (P < 0.05). There was no difference in ST-T wave changes after surgery, and no patient had an elevation in troponin I levels. Postoperative variables were similar except that patients who received iso/fen had lower Stewart recovery scores during the first 15 minutes after post anesthesia care unit admission and a higher incidence of nausea and vomiting the day after surgery, whereas patients receiving remi/prop had discharge delays secondary to hypertension. ICU admittance, time to first void, oral intake, and time to hospital discharge were similar between the groups. At 9 times the cost of an iso/fen anesthesia technique, remi/prop offers little advantage over inhalational anesthesia for carotid endarterectomy.

Aged↗

PubMed2003

The effect of spinal bupivacaine in combination with either epidural clonidine and/or 0.5% bupivacaine administered at the incision site on postoperative outcome in patients undergoing lumbar laminectomy.

UNLABELLED: Spinal anesthesia has numerous advantages over general anesthesia for patients undergoing lumbar laminectomy and microdisk surgery. In this study, we evaluated the addition of epidural clonidine and/or bupivacaine, injected at the incision site, on postoperative outcome variables in patients undergoing lower spine procedures using spinal anesthesia. One hundred twenty patients having lumbar spine surgery received bupivacaine spinal anesthesia supplemented by 150 microg of epidural clonidine with or without incisional bupivacaine, epidural placebo plus incisional bupivacaine, or placebo with incisional saline. Demographic data, intraoperative hemodynamics, blood loss, pain, nausea, urinary retention, hospital discharge, and other variables were compared by using either analysis of variance or chi(2) analysis. Demographics were similar. IV fluids, blood loss, incidence of intraoperative bradycardia, and hypotension were not different among groups. Postanesthesia care unit pain scores were lower and demand for analgesics was less in patients who received both the clonidine and subcutaneous bupivacaine. Patients who received epidural clonidine also had improved postoperative hemodynamics. Hospital discharge, urinary retention, and other variables were not different. We conclude that epidural clonidine as a supplement to spinal anesthesia produced no perioperative complications and improved postoperative pain and hemodynamic stability in patients undergoing lower spine procedures. IMPLICATIONS: Spinal anesthesia with supplemental epidural clonidine in combination with incision site subcutaneous bupivacaine was evaluated both intra- and postoperatively and compared with spinal anesthesia alone for lower lumbar spine procedures. Both epidural clonidine and subcutaneous incisional bupivacaine, added to spinal anesthesia for lumbar spine surgery, improves pain relief and reduces the need for postoperative opioids with their associated side effects.

Adrenergic alpha-Agonists↗

PubMed2002

Perioperative management of complex skull base surgery: the anesthesiologist's point of view.

The anesthetic management of complex skull base surgical procedures provides unique problems and concerns for the neuroanesthesiologist. Positioning to access the skull base could put the patient at risk for peripheral nerve injury and some of the positions may increase the risk for air emboli. In addition, tumor pathology and involvement with vital structures could increase the chances for substantive blood loss, destruction of associated nerves or vessels, and may require temporary occlusion of the carotid artery necessitating intraoperative neuroprotection. Neurophysiological monitors may also be used to safeguard nerve function and anesthetic techniques must be adjusted to accommodate their use. Finally, postoperative morbidity may be affected by surgical approach to the skull base and the anesthesiologist should be aware of which approach may produce a greater incidence of pain, nausea, and vomiting in the postoperative period. The authors discuss the anesthetic concerns and management for complex cranial base surgery. Different approaches will be discussed and comparisons of perioperative parameters between these approaches will be made with data provided by retrospective chart review of more than 600 skull base procedures performed at the authors' institution over the last 10 years. This information should help guide decision making concerning anesthetic management for these skull base procedures.

Anesthesia, General↗