Faster wash-out and recovery for desflurane vs sevoflurane in morbidly obese patients when no premedication is used

Background: The aim of this study was to compare desflurane vs sevofluranekinetics and dynamics in morbidly obese patients and their recoveryprofile when no premedication had been used. Methods: Twenty-eight unpremedicated obese patients were randomly allocatedto receive either sevoflurane (n = 14) or desflurane (n = 14)as the main anaesthetic agent. After induction of anaesthesia,either sevoflurane 2% or desflurane 6% was administered for30 min via a non-rebreathing circuit. The kinetics of sevofluraneand desflurane were determined by measuring and recording end-tidalsamples during this time. The bispectral index was used to indicatethe level of hypnosis. At the end of the procedure, the end-tidalconcentrations of sevoflurane and desflurane were recorded duringthe first 5 min after stopping their administration. Time fromdiscontinuation of the anaesthetic drugs to eye opening on verbalcommand, squeezing the observer's hand on command, extubation,stating their name, giving their correct date of birth, dischargefrom the recovery room, and duration of the surgery and anaesthesiawere also recorded. Results: The F_A/F_I ratio was significantly higher in the desflurane groupfrom the 15th to the 30th min. The wash-out phase was fasterfor desflurane during the total observation period. When desfluranewas used, recovery was also faster. Conclusions: Desflurane provides faster wash-in and wash-out than sevofluranein morbidly obese patients, and recovery is much faster afterdesflurane administration when no premedication has been used.     

Anaesthesia for the morbidly obese patient

Canadian Journal of Anesthesia/Journal canadien d'anesthésie -     

Optimization of desflurane administration in morbidly obese patients: a comparison with sevoflurane using an 'inhalation bolus' technique

Background. The concept of an ‘inhalation bolus’can be used to optimize inhaled drug administration. We investigatedthe depth of anaesthesia, haemodynamic stability, and recoverytime in morbidly obese patients resulting from bispectral index^TM(BIS^TM)-guided sevoflurane or desflurane administration andBIS-triggered inhalation boluses of sevoflurane or desfluranecombined with titration of remifentanil. Methods. Fifty morbidly obese patients undergoing laparoscopicgastroplasty received either BIS-guided sevoflurane or desfluraneanaesthesia in combination with a remifentanil target-controlledinfusion. Intraoperative haemodynamic stability and BIS controlwere measured. Immediate recovery was recorded. Results. Intraoperatively, the BIS was between 40 and 60 fora greater percentage of time in the sevoflurane (78 (13)% ofcase time) than in the desflurane patients (64 (14)% of casetime), owing to too profound anaesthesia in the desflurane patientsat the start of the procedure. However, fewer episodes of hypotensionwere found in the desflurane group, without the occurrence ofmore hypertensive episodes. During immediate recovery, eye opening,extubation, airway maintenance, and orientation occurred soonerin the desflurane group. Conclusions. Immediate recovery was significantly faster inthe desflurane group. Overall hypnotic controllability measuredby BIS was less accurate with desflurane. Overall haemodynamiccontrollability was better when using desflurane. Fewer episodesof hypotension were found in the desflurane group. The use ofthe inhalation bolus was found to be appropriate in both groupswithout causing severe haemodynamic side effects. Minimal BISvalues were significantly lower after a desflurane bolus. Br J Anaesth 2003; 91: 638–50     

Positioning the morbidly obese patient for anesthesia

Each of the different positions employed during surgery can compromise cardiopulmonary function in the morbidly obese patient. An understanding of the physiologic changes that can occur is essential for the successful management of these patients.     

Emergence and recovery characteristics of desflurane versus sevoflurane in morbidly obese adult surgical patients: a prospective, randomized study

We compared postoperative recovery after desflurane (n = 25) versus sevoflurane (n = 25) anesthesia in morbidly obese adults (body mass index >/=35) who underwent gastrointestinal bypass surgery via an open laparotomy. After premedication with midazolam and metoclopramide 1 h before surgery, epidural catheter placement, induction of anesthesia with fentanyl and propofol, and tracheal intubation facilitated with succinylcholine, anesthesia was maintained with age-adjusted 1 minimum alveolar concentration (MAC) desflurane or sevoflurane. Fentanyl IV, morphine or local anesthetics epidurally, and vasoactive drugs as needed were used to maintain arterial blood pressure at +/-20% of baseline value and to keep bispectral index of the electroencephalogram values between 40 to 60 U. Although patients were anesthetized with desflurane for a longer time (261 +/- 50 min versus 234 +/- 37 min, mean +/- sd; P < 0.05, desflurane versus sevoflurane, respectively) and for more MAC-hours (4.2 +/- 0.9 h versus 3.7 +/- 0.8 h; P < 0.05), significantly earlier recovery of response to command and tracheal extubation occurred in patients given desflurane than in patients given sevoflurane. The modified Aldrete score was greater in desflurane-anesthetized patients on admission to the postanesthesia care unit (PACU) (P = 0.01) but not at discharge (P = 0.47). On admission to PACU, patients given desflurane had higher oxygen saturations (97.0% +/- 2.4%) than patients given sevoflurane (94.8% +/- 4.4%, P = 0.035). Overall, the incidence of postoperative nausea and vomiting and the use of antiemetics did not differ between the two anesthetic groups. We conclude that morbidly obese adult patients who underwent major abdominal surgery in a prospective, randomized study awoke significantly faster after desflurane than after sevoflurane anesthesia and the patients anesthetized with desflurane had higher oxygen saturation on entry to the PACU.     

Desflurane versus sevoflurane for laparoscopic gastroplasty in morbidly obese patients

STUDY OBJECTIVE: To determine if desflurane results in a faster emergence as measured by time to eye opening compared to sevoflurane in morbidly obese patients undergoing laparoscopic gastroplasty. STUDY DESIGN: Prospective, randomized, double-blinded study. SETTING: Tertiary care hospital. PATIENTS: 70 patients with a body mass index of 35 or higher undergoing laparoscopic gastroplasty. INTERVENTIONS: Patients were randomized into two groups to receive either desflurane or sevoflurane for maintenance of general anesthesia. MEASUREMENTS: Intraoperative measured variables included the time from when the inhalation agent was turned off (no agent delivered) to eye opening and the time from when the inhalation agent was turned off to extubation. Postanesthesia care unit (PACU)-measured variables on admission and at 15 minute intervals until discharge included oxygen saturation (Spo2), blood pressure, heart rate, pain and nausea Visual Analog Scale (VAS) scores, emesis, modified Aldrete score, and Mini-Mental Status (MMS) examination score. MAIN RESULTS: No differences were noted in demographic data, total surgical operative time, times from turning inhalation agent off to eye opening and extubation, or average length of stay in PACU. No differences were noted with respect to pain VAS, treatment for pain, modified Aldrete scores, emesis, or treatment for postoperative nausea or emesis. Differences were noted in PACU nausea VAS at 15 minutes, PACU nausea VAS at discharge, and PACU-MMS score at 45 minutes; however, multivariate analysis of variance revealed no differences between groups over the repeated PACU measured time periods in nausea VAS (P=0.17) or in MMS (P=0.34). Higher heart rates in the desflurane group were observed during PACU admission (82.3+/-9.8 vs 74.4+/-13.4 bpm, P<0.01) and 15 minutes post PACU admission (79.4+/-12.1 vs 71.3+/-13.2 bpm, P=0.01). CONCLUSIONS: In morbidly obese patients undergoing laparoscopic gastroplasty, emergence, as measured by time to eye opening, did not differ between desflurane and sevoflurane, with similar recovery characteristics.     

Lateral decubitus position for percutaneous nephrolithotripsy in the morbidly obese or kyphotic patient

BACKGROUND AND PURPOSE: Morbidly obese or debilitated patients do not tolerate the prone position used for percutaneous nephrolithotripsy (PCNL) well and may suffer from severe cardiorespiratory compromise in this position. The purpose of this study is to demonstrate a simple way to overcome this difficulty. PATIENTS AND METHODS: Two morbidly obese patients, ages 48 and 32 years, with Body Mass Indices of 47.5 and 43.2 and a 68-year old patient severely debilitated by multiple cerebral infarctions, ischemic heart disease, and kyphosis suffered from relatively high renal stone burdens. For PCNL, the patients were placed in the lateral decubitus position. To obtain an anteroposterior projection in this position, the C-arm fluoroscopy unit was tilted to one side and the operating table to the other. Tract dilation, stone fragmentation, and fragment extraction were performed with the patient in this position. RESULTS: An attempt to perform PCNL in the prone position in the first patient was aborted because of severe hypoxemia and hypercarbia. In the lateral decubitus position, the procedures were easily performed in all patients without any complications. It was noted that by rotating the C-arm to a perpendicular position, it was possible to perform nephroscopy and use fluoroscopy simultaneously. CONCLUSION: We highly recommend using the lateral position for PCNL in morbidly obese patients and in patients suffering from kyphosis. This position is safe and convenient.     

An alternative anesthetic technique for the morbidly obese patient undergoing endovascular repair of an abdominal aortic aneurysm

Abdominal aortic aneurysms have been treated by open operative repair for many years. A frequent rate of morbidity is associated with the natural history of abdominal aortic aneurysms in combination with open surgical repair. Recently a new technique that is less surgically invasive has been developed as an alternative to open repair. The present case report outlines a less invasive anesthetic technique for the morbidly obese patient. IMPLICATIONS: This case report discusses a minimally invasive anesthetic approach towards the morbidly obese patient undergoing endovascular abdominal aortic aneurysm repair. It demonstrates a safe and cost-effective means of managing a patient with numerous comorbidities. We also discuss an anesthetic/surgical approach on how to provide maximum analgesia with minimal anesthesia.     

Case report: Rhabdomyolysis in morbidly obese patients: anesthetic considerations

Purpose

We report the presentation and management of rhabdomyolysis involving shoulder girdle and upper arm muscles in a morbidly obese patient after prolonged laparoscopic surgery.

Clinical features

A 41-yr-old morbidly obese woman presented for laparoscopic abdominal hysterectomy. She had hypertension and type II diabetes which were controlled on regular medications. She also had obstructive sleep apnea. Her clinical examination and investigations revealed no abnormality except morbid obesity (body mass index 54 kg·m^-2) and left ventricular hypertrophy on transthoracic echocardiogram. Standard general anesthesia was administered under baseline non-invasive monitors. Succinylcholine was used to secure the airway during anesthetic induction. Surgery was performed with the patient positioned with a 15° head-down tilt, and it took six hours to complete the procedure as technical difficulty was encountered due to her body habitus. Her trachea was extubated and she was transferred to the postanesthetic care unit (PACU) without incident. In the PACU, the patient complained of severe bilateral arm pain and weakness an hour after surgery. On physical examination, she exhibited limited movement of her arms against gravity while complaining of tenderness in her shoulder girdle muscles and both arms. Clinical suspicion of rhabdomyolysis based on her signs and symptoms was confirmed by an elevated serum creatinine kinase (CK) of 18,392 IU·L^-1 and serum potassium of 5.3 mmol·L^-1. Intravenous crystalloids and mannitol were administered for 24 hr for renal protection, and her clinical symptoms and serum CK levels improved over seven days. The patient was discharged to home on the tenth postoperative day, and she continued to improve over the three-month follow-up period.

Conclusions

Morbidly obese patients who undergo prolonged surgery are at risk for rhabdomyolysis, and early diagnosis and therapy are required to prevent severe complications.     

Anaesthesia for LSCS in a morbidly obese patient

The management of a morbidly obese parturient with a body mass index of 88 is reported. She developed asthma during the pregnancy. Lumbar epidural anaesthesia was successfully used for an elective caesarean section and tubal ligation.     

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.     

Orthopedic trauma surgery in the morbidly obese patient

Purpose

The treatment of morbidly obese patients in orthopedic trauma differs in many ways compared to injured patients with normal body mass indices. This paper highlights key differences and ways to overcome obstacles.

Methods

We present specific tips, as well as considerations for initial planning, positioning for surgery, intra-operative strategies, and a discussion on both anesthesia and imaging.

Results

Several treatment strategies have been shown to have better results in morbidly obese patients. Pre-operative planning is necessary for minimizing risk to the patient.

Conclusion

The prevalence of morbid obesity has increased in the USA in the past quarter century. Treatment for orthopedic injuries in morbidly obese patients requires a multidisciplinary approach that addresses not only their orthopedic injuries, but also medical co-morbidities. A team of medicine doctors, anesthesiologists, X-ray technicians, physical and occupational therapists, respiratory therapists, and social workers is needed in addition to the orthopedic surgeon. Modifications in both pre-operative planning and intra-operative strategies may be necessary in order to accommodate the patient. This paper presents numerous technical tips that can aid in providing stable fixation for fractures, as well as addressing peri-operative issues specific to the morbidly obese.     

Postoperative recovery after desflurane, propofol, or isoflurane anesthesia among morbidly obese patients: a prospective, randomized study

Recovery from anesthesia might be compromised in obese patients. Because of its pharmacological properties, desflurane might allow rapid postoperative recovery for these patients. We compared postoperative recovery for 36 obese patients randomized to receive either desflurane, propofol, or isoflurane to maintain anesthesia during laparoscopic gastroplasties. Anesthesia was induced with propofol and succinylcholine IV and was maintained with rocuronium, alfentanil, inhaled nitrous oxide, and the study drug. Immediate recovery (i.e., times from the discontinuation of anesthesia to tracheal extubation, eye opening, and the ability to state one's name) was measured. At the time of postanesthesia care unit (PACU) admission, arterial saturation and the ability of patients to move were recorded. In the PACU, intermediate recovery was measured by using sedation and psychometric evaluations, 30, 60, and 120 min postoperatively. Data were compared between groups by using the Kruskal-Wallis and chi(2) tests. Results were reported as means +/- SD. P: < 0.05, compared with desflurane, was considered significant. Immediate recovery occurred faster, and was more consistent, after desflurane than after propofol or isoflurane (times to extubation were 6 +/- 1 min, 13 +/- 8 min [P: < 0.05, compared with desflurane], and 12 +/- 6 min [P: < 0.05, compared with desflurane], respectively). At PACU admission, SpO(2) values were significantly higher and patient mobility was significantly better after desflurane than after isoflurane or propofol. Sedation was significantly less pronounced with desflurane at 30 and 120 min postoperatively. In morbidly obese patients, postoperative immediate and intermediate recoveries are more rapid after desflurane than after propofol or isoflurane anesthesia. This advantage of desflurane persists at least for 2 h after surgery and is associated with both an improvement in patient mobility and a reduced incidence of postoperative desaturation. Implications: In morbidly obese patients, postoperative immediate and intermediate recoveries are more rapid and consistent after desflurane than after propofol or isoflurane anesthesia.