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S Ganapathy

Publications and source records attributed to S Ganapathy.

At least 19 recordsLinked to original sources
PubMed2000

Elastomeric pumps for ambulatory patient controlled regional analgesia.

PURPOSE: To report our experience with the use of the (Eclipse) elastomeric pump for ambulatory Patient Controlled Regional Analgesia (PCRA) METHOD: After a pilot study using this device in patients admitted to the hospital, seven patients received PCRA at home using the elastomeric pump. Patients with a variety of continuous regional anesthetic blocks were sent home with written and verbal instructions regarding the use of this device, boluses, side effects of local anesthetics and removal of block catheters. Patients were contacted daily to collect data with regards to the efficacy of the block, problems associated with the use of this device and their satisfaction with the method of analgesia. RESULTS: During the pilot study there were two catheter disconnections requiring rescue analgesics. Two patients had the entire contents of the bulb delivered over several minutes. Among the seven patients receiving PCRA at home, one patient had to be admitted to the hospital. One patient had block catheter slip out during transit. The volume delivered could not be measured. Patients found it difficult to know if the drug had been delivered. Three patients noted that the pumps were empty earlier than expected. One patient found it difficult to change the bulb. No patient had difficulty with catheter removal or with bolusing. CONCLUSIONS: PCRA offers excellent postoperative analgesia at home. Elastomeric pumps facilitate PCRA but are imprecise with drug delivery and may not be safe for epidural infusions. The safety of this device for peripheral nerve blocks should be evaluated further.

Adult↗
PubMed2000

Robot-assisted computer enhanced closed-chest coronary surgery: preliminary experience using a Harmonic Scalpel and ZEUS.

BACKGROUND: Successful endoscopic harvesting of arterial conduits is critical to the performance of totally endoscopic bypass grafting. Recent success with computer-enhanced robotic systems in the performance of endoscopic single vessel coronary artery bypass (ENDOCAB) has paved the way for developing techniques for multivessel ENDOCAB. The Harmonic Scalpel (Ethicon Endo-Surgery, Cincinnati, OH) has previously demonstrated versatility and efficacy in manual endoscopic internal thoracic artery (ITA) harvesting. This study was undertaken to determine the feasibility of adapting this technology to a robotic telemanipulation system and its safety and efficacy in telerobotic ITA harvesting. METHODS: The Harmonic Scalpel was adapted to the ZEUS robotic surgical system (Computer Motion, Goleta, CA) and used to harvest the ITA in 19 patients undergoing multivessel off-pump coronary artery bypass (OPCAB) surgery. With the left lung collapsed, the ITA was harvested in all patients with CO2 insufflation through three 5 mm ports in the left chest. Postoperative angiography and transthoracic Doppler studies were performed in all patients. RESULTS: There were no ITA injuries and patients tolerated insufflation without hemodynamic compromise. Side branches were controlled easily without bleeding. Average ITA harvest time was 65 +/- 21 minutes. All vessels were patent after harvesting and demonstrated no angiographic evidence of injury. CONCLUSIONS: This paper demonstrates a technique by which the Harmonic Scalpel can be readily adapted to the ZEUS robotic telemanipulation system. Using this system, ITA's can be safely harvested totally endoscopically within a reasonable time frame for patients undergoing ENDOCAB.

Coronary Angiography↗
PubMed1999

A multicentre trial of ropivacaine 7.5 mg x ml(-1) vs bupivacaine 5 mg x ml(-1) for supra clavicular brachial plexus anesthesia.

PURPOSE: To compare the efficacy of ropivacaine 7.5 mg x ml(-1) with bupivacaine 5.0 mg x ml(-1) for subclavian perivascular brachial plexus block. METHODS: After informed consent, 104 ASA I-III adults participated in a randomized, double-blind, multi-center trial to receive 30 ml of either ropivacaine 7.5 mg x ml(-1) or bupivacaine 5.0 mg x ml(-1) for subclavian perivascular brachial plexus block prior to upper limb surgery. Onset and duration of sensory and motor block in the distribution of the axillary, median, musculo-cutaneous, radial and ulnar nerves were assessed. RESULTS: Onset times and duration of sensory and motor block were similar between groups. Mean duration of analgesia for the five nerves was between 11.3 and 14.3 hr with ropivacaine and between 10.3 and 17.1 hr with bupivacaine. Quality of muscle relaxation judged as excellent by the investigators was not significantly different (ropivacaine - 35/49, bupivacaine - 30/49). The median time to first request for analgesia was comparable between the two groups (11-12 hr). One patient developed a grand mal seizure shortly after receiving bupivacaine and recovered consciousness within 30 min. There were no serious adverse events in the ropivacaine group. CONCLUSIONS: Thirty ml ropivacaine 7.5 mg x ml(-1) (225 mg) produced effective and well tolerated brachial plexus block of long duration by the subclavian perivascular route. In this study, the results were similar to those of 30 ml bupivacaine 5.0 mg x ml(-1).

Adolescent↗
PubMed1999

Beating heart surgery: why expect less central nervous system morbidity?

BACKGROUND: The incidence and etiology of brain dysfunction after conventional coronary artery bypass surgery using cardiopulmonary bypass (CPB) are reviewed. METHODS: Stroke rates and incidences of cognitive dysfunction from various studies are considered. Mechanisms of injury including cerebral embolization as detected by transcranial Doppler and retinal angiography, and imaging-based evidence for postoperative cerebral edema, are discussed. Preliminary results from a prospective clinical trial assessing cognitive dysfunction after beating heart versus conventional coronary artery bypass with CPB are discussed. RESULTS: Initial evidence for lower overall postoperative morbidity, and for a lower incidence of cognitive dysfunction specifically, after nonpump coronary revascularization is presented. CONCLUSIONS: Beating heart surgery results in less potential for generation of cerebral emboli and appears to produce a lower incidence of cognitive dysfunction in both short- and intermediate-term postoperative follow-up periods as compared with conventional coronary artery bypass surgery using CPB.

Cardiopulmonary Bypass↗
PubMed1999

Zinc, exercise, and thyroid hormone function.

During the last 3 decades, remarkable advances have taken place in the field of zinc metabolism. Thirty years ago, only three enzymes that required zinc for their activities were identified; today more than 200 such enzymes have been classified. Zinc plays a vital role in human nutrition and biochemical function. Prior to 1963, zinc deficiency in humans was unknown. Today, it is recognized that a nutritional deficiency of zinc is common throughout the world, including the U.S.A marginal deficiency of zinc appears to be prevalent in many segments of populations in developed countries, and more severe deficiencies are widespread in many parts of the world. Therefore, it is important that proper steps to correct zinc deficiency are taken. However, the assessment of zinc nutriture has always proven to be a difficult problem because no reliable measure of zinc status currently exists. More recently, it has been recognized that zinc may play an important role in thyroid hormone metabolism, although the exact mechanism by which zinc affects thyroid hormone function is far from clear. In addition, exercise has been shown to alter zinc status. This review will focus on the relationship among zinc status, exercise, and thyroid hormone function.

Animals↗
PubMed1999

Sameridine is safe and effective for spinal anesthesia: a comparative dose-ranging study with lidocaine for inguinal hernia repair.

UNLABELLED: Sameridine is a new compound with local anesthetic and analgesic properties when injected intrathecally. We studied the anesthetic and analgesic efficacy of three doses of isobaric sameridine (15, 20, and 23 mg) compared with 100 mg of hyperbaric lidocaine for spinal anesthesia in 140 healthy male patients undergoing inguinal hernia repair. Patients received spinal anesthesia with 4 mL of the study drug injected at the L2-3 or L3-4 interspace in the lateral decubitus position. All three doses of sameridine provided spinal anesthesia similar to lidocaine, with a slightly longer time to reach peak block height. The failure rate was highest in the 15-mg sameridine group, and accrual was discontinued in that group after 35 patients. The duration of blockade was shorter with lidocaine, but the time to voiding and ambulation was similar in all groups. Patients receiving sameridine were less likely to request morphine for postoperative analgesia and were less likely to request any analgesia in the first 4 h after injection of the drug. Use of oral analgesics (hydrocodone and acetaminophen) was similar in all groups after the first 4 h of the 24-h observation. We conclude that, in the three doses studied, sameridine provided spinal anesthesia similar to lidocaine, but with residual analgesia after drug injection that reduced the need for systemic analgesics in the first 4 h postoperatively. IMPLICATIONS: In this clinical trial, we show the potential efficacy of a class of drugs that can produce both spinal anesthesia and postoperative analgesia when used for hernia repair.

Adolescent↗
PubMed1999

Should renal ultrasonography be done routinely in children with first urinary tract infection?

To reassess the impact of renal ultrasonography on the care of children with first febrile urinary tract infection (UTI) we conducted a computer search and review of medical records of (1) all children who were admitted to our hospital with first febrile urinary tract infection and underwent renal ultrasonography during a 25-month period beginning February 1, 1995, (2) all children diagnosed by ultrasound to have hydronephrosis during the same time period. Of a total of 124 patients with UTI, renal ultrasound appeared normal or showed evidence of acute pyelonephritis in 105 (84.7%), and in another nine (7.2%) it showed only minor findings. In 10 children (8.1%) ultrasound showed hydronephrosis and/or hydroureter. In eight of the latter 10, voiding cystourethrography showed vesicoureteral reflux; in one, posterior urethral valves; and in one, who had a unilateral nonobstructed dilatated system, cystography appeared normal. Except for the last patient, who was given prophylactic antibiotics and continued to have urinary tract infections, in no other case did ultrasound alone have any impact on the patient's management. Four children with both abnormal-appearing renal ultrasound and voiding cystourethrography required surgical intervention. One hundred of the 124 children had a voiding cystourethrogram. In 38 children it detected vesicoureteral reflux and, in another two, bladder abnormalities. Thirty-five of those with abnormal-appearing cystogram but without an indication for surgery were given prophylactic antibiotics. During the same 25-month period, 63 children without urinary tract infection were diagnosed by ultrasound with hydronephrosis. In 45 of them (71.4%) the urologic abnormality had already been detected by prenatal ultrasound. Fourteen of these 45 children (31.1%) required surgery, all for congenital anomalies related to obstructive uropathy. We conclude that routine renal ultrasonography in children with first urinary tract infection has negligible influence on their clinical management. This seems to be due to the recent widespread use, in industrialized countries, of maternal-fetal ultrasonography, which already detects a significant number of children with congenital obstructive uropathy prenatally. On the other hand imaging of the lower urinary tract is of high yield and contributes significantly to patient care. Therefore, whereas imaging of the lower urinary tract should continue to be done routinely in children with first urinary tract infection, renal ultrasound may be reserved for more select cases.

Female↗
PubMed1999

Modified continuous femoral three-in-one block for postoperative pain after total knee arthroplasty.

UNLABELLED: We prospectively studied the continuous "modified" femoral three-in-one block for postoperative pain after total knee arthroplasty. Sixty-two patients undergoing elective knee arthroplasty under spinal anesthesia with bupivacaine (B) and fentanyl were randomized to receive 0.2% B, 0.1% B, or placebo at 10 mL/h for 48 h after an initial bolus of 30 mL of the same solution via the femoral block catheter. The catheters were inserted under the fascia iliaca using a "double pop" technique and a peripheral nerve stimulator and were advanced 15-20 cm cranially. Venous plasma levels of B, desbutylbupivacaine, and 4-hydroxy B were measured daily for 3 days. All patients received patient-controlled analgesia with morphine and indomethacin suppositories for 48 h. Using computed tomography, we evaluated the catheter location for 20 patients. The catheter tips, located superior to the upper third of the sacroiliac joint in the psoas sheath, were labeled as ideally located. The group receiving 0.2% B had a larger block success rate, smaller morphine consumption in the immediate postoperative period (15 vs 22 mg) and during the first postoperative day (9 vs 18 mg), and achieved a greater range of motion in the immediate postoperative period (91 degrees +/- 10 degrees vs 80 degrees + 13 degrees ). Visual analog scores for pain during both rest and activity were low but similar between the groups. Forty percent of the catheters evaluated were ideally located. Ideal location and use of 0.2% B resulted in 100% success of blockade of all three nerves. The S1 root was blocked in up to 76% of patients. The plasma levels of B, 4-hydroxy B, and desbutylbupivacaine were below the toxic range during the infusion. We conclude that continuous fascia iliaca block with 0.2% B results in opioid-sparing and improved range of motion during the immediate postoperative period. Larger doses of bupivacaine may safely be used in the immediate postoperative period if needed. IMPLICATIONS: Continuous fascia iliaca block with 0.2% bupivacaine reduces opioid requirements and improves range of motion in the immediate postoperative period compared with a placebo and 0.1% bupivacaine. Plasma levels are below the toxic range with this dose. Only 40% of the catheters are positioned in the ideal location. With the smaller dose of bupivacaine, the success rate with this block is small.

Aged↗
PubMed1998

Characterization of silicon sites in monoclinic zeolite ZSM-5 using 29Si magic angle spinning (MAS) nuclear magnetic resonance (NMR) and molecular modelling.

An attempt has been made to correlate the experimentally observed 29Si MAS NMR chemical shifts of monoclinic phase of highly siliceous ZSM-5 with their electronic properties. In order to incorporate the influence of next neighbor atoms on the 29Si chemical shielding of central SiO4, a pentameric cluster model (H12Si5O16) has been chosen. Each of the 24 crystallographically distinct Si sites, of ZSM-5 framework has been modelled by such cluster models. Based on semi-empirical quantum chemical calculations, a multiple linear regression analysis of the various electronic properties with the 29Si chemical shifts has been attempted. The relative difference in 29Si chemical shifts for the Si sites in ZSM-5 is reasonably accounted, although quantitative prediction may require non-empirical quantum chemical calculations.

Crystallography↗
PubMed1997

Propofol patient-controlled sedation during hip or knee arthroplasty in elderly patients.

PURPOSE: Little information is available regarding the use of patient-controlled sedation (PCS) among the elderly. This study evaluated the safety and efficacy of propofol PCS among elderly patients undergoing hip or knee arthroplasty. METHODS: Forty patients, aged 65-78 yr, undergoing hip or knee arthroplasty under regional anaesthesia were randomized to receive propofol PCS (dose = 0.3 mg.kg-1, delay = three min; n = 20) or anaesthetist-administered midazolam-fentanyl sedation (n = 20). Sedation, anxiety and discomfort visual analogue scores (VAS) were measured, by an independent observer, preoperatively, immediately at the end of surgery and one hour following admission to the postanaesthetic care unit (PACU). Cognition was evaluated, using an abbreviated Mini Mental Status Examination, preoperatively and in the PACU. Patient satisfaction, based on VAS and a brief questionnaire, was measured in the PACU. The incidence of intraoperative complications was also compared. RESULTS: Patient satisfaction was high in each group. Sedation and anxiety VAS were similar in each group. A high incidence of pain with drug injection was noted among patients receiving propofol (80%). Transient deeper levels of sedation (6 vs 1; P = 0.05) were observed more commonly in the propofol PCS group. CONCLUSION: Propofol PCS provides effective sedation. Using a propofol dose of 0.3 mg.kg-1, transient episodes of deeper sedation were noted more frequently among patients receiving PCS. These episodes did not require intervention but, suggest that this propofol PCS dose approaches the limit of safety and should be further reduced for some elderly patients.

Adjuvants, Anesthesia↗
PubMed1996

Solid-state CP/MASS 13C-NMR spectroscopy: a sensitive method to monitor enzymatic hydrolysis of chitin.

The time-course hydrolysis of colloidal chitin by the chitinase complex isolated from Myrothecium verrucaria was monitored using solution and solid-state 13C-NMR spectroscopy. The solution NMR studies showed the presence of N-acetylglucosamine (GlcNAc) as the sole product of hydrolysis. Solid-state 13C CP/MASS studies, on the other hand, indicated the presence of high molecular weight oligomers as well as GlcNAc. The linewidth of the C1 carbon of the oligomers obtained after hydrolysis is found to be less than that of the unhydrolyzed sample. The linewidths calculated from the spin-spin relaxation times (T2) of colloidal chitin and its products of hydrolysis were in the restricted range of 40-50 Hz, compared with the observed linewidths of 143-123 Hz. Peak area measurement on monomer to polymer/oligomer indicated an initial slow formation of the monomer, GlcNAc. From the NMR data, the involvement of endo-enzymes in the initial phase of hydrolysis is suggested.

Acetylglucosamine↗
PubMed1996

Eutectic mixture of local anaesthetics is not effective for extracorporeal shock wave lithotripsy.

PURPOSE: Eutectic mixture of local anaesthetics (EMLA) produces cutaneous analgesia. This randomized, double blind, placebo controlled study evaluated the efficacy of EMLA cream during extracorporeal shock wave lithotripsy (ESWL) using the Dornier MFL 5000 lithotripter. METHODS: Patients scheduled to undergo lithotripsy of renal or pelviureteric junction stones were randomized to receive either 30 g EMLA cream (E) or placebo (P) over the kidney area 60-90 min before the procedure. During lithotripsy all patients received alfentanil via a PCA machine (dose--10 mu.kg-1, lockout time--three minutes, no basal infusion). Additional bolus doses of 5 micrograms.kg-1 alfentanil were administered by the anaesthetist if analgesia was inadequate. Visual analogue scores (VAS) for pain were documented prior to application of the cream. On arrival in the post anaesthesia care unit VAS pain scores were documented for maximum pain and average pain felt during the procedure as well as for satisfaction of the analgesic technique used. Total time spent in the PACU and the Aldrete scores on arrival were compared. RESULTS: Eighty-three patients completed the study. Demographic data were similar between the two groups. Also, VAS for maximal pain, average pain and satisfaction and the total number of shock waves were similar although the EMLA group received more shock waves at the lower energy level (kV) (P < 0.0001). Total dose of alfentanil, dose as boluses, rate of alfentanil use, total number of PCA attempts and missed attempts were similar. The incidence of adverse events such as bradypnoea, airway obstruction, transient hypoxaemia, pruritus and nausea were small and similar. There was a slightly higher incidence of inadequate analgesia documented by the anaesthetist in the EMLA group. There was no difference between the groups with regards to duration of stay in the PACU, incidence of nausea or Aldrete scores on admission to PACU. CONCLUSIONS: During lithotripsy EMLA cream does not modify the pain perceived nor does it have any opioid sparing effect. It does not facilitate early discharge from the PACU.

Adult↗
PubMed1996

Continuous epidural infusion of ropivacaine for the prevention of postoperative pain after major orthopaedic surgery: a dose-finding study.

PURPOSE: A dose-finding study to investigate the use of epidural infusions of ropivacaine for postoperative analgesia following orthopaedic surgery. METHODS: This was a randomized, double-blind study. Surgery was performed using a combination of a lumbar epidural block utilizing ropivacaine 0.5% and a standardized general anaesthetic. Postoperatively, an epidural infusion of the study solution (saline, ropivacaine 0.1%, 0.2% or 0.3%) was started at the rate of 10 ml.hr-1 and continued for 21 hr after arrival in the PACU. Analgesia was supplemented with PCA morphine (dose = 1.0 mg, lock-out = 5 min). RESULTS: Forty-four patients completed the study. The ropivacaine 0.1%, 0.2%, 0.3% groups required less morphine over the 21 hr than the saline group (P < 0.01). The VAS pain scores were also lower in the three ropivacaine groups (P < 0.001). The ropivacaine groups maintained sensory anaesthesia to pinprick when compared with saline (P < 0.05). The motor block in the 0.3% group was significantly higher than the saline group at all times (P < 0.05), and higher than the 0.1% group at eight hours (P < 0.01), while the 0.2% group had higher Bromage scores than saline at 4 and 21 hr (P < 0.05). CONCLUSIONS: The use of continuous epidural infusions of ropivacaine 0.1%, 0.2% and 0.3% at 10 ml.hr-1 improved postoperative pain relief and decreased PCA morphine requirements in patients undergoing major orthopaedic surgery. The 0.1% and 0.2% concentrations produced similar sensory anaesthesia with less motor blockade than the 0.3% concentration.

Adult↗
PubMed1996

Postoperative cognitive impairment in the elderly. Choice of patient-controlled analgesia opioid.

This study evaluated the safety and cognitive impact of patient-controlled analgesia with fentanyl compared to patient-controlled analgesia with morphine among elderly postoperative patients. In addition, two screening tests for cognitive impairment, the Mini Mental Status Exam and the Short Portable Mental Status Questionnaire, were compared. Ninety-six elderly patients were randomly allocated to receive patient-controlled analgesia with either fentanyl or morphine following hip or knee arthroplasty. Patients were evaluated postoperatively for clinical confusion, cognitive function test results, adequacy of analgesia, drug use and complications. Fentanyl produced less depression in postoperative cognitive function compared to morphine. The incidence of clinical confusion was not statistically different between groups (4.3% for fentanyl versus 14.3% for morphine). Fentanyl patients used more opioid based on a dose ratio of 100:1 suggesting that this dose ratio is inadequate. The incidence of urinary retention was lower in the fentanyl group. A poor agreement between the two tests of cognitive impairment mandates caution when peri-operative cognitive function is compared using different tests.

Aged↗
PubMed1995

A controlled clinical trial of short-course chemotherapy for tuberculoma of the brain.

OBJECTIVE: The efficacy of a short-course regimen in the treatment of brain tuberculoma and computerised tomography (CT) scan appearance before, during and after antituberculosis treatment was studied in a controlled clinical trial. DESIGN: Patients aged over 5 years with tuberculoma of the brain diagnosed by CT scan were randomly allocated to one of the following 2 regimens: Regimen 1: rifampicin, isoniazid and pyrazinamide daily for an initial 3 months followed by rifampicin and isoniazid twice-weekly for 6 months. Regimen 2: rifampicin, isoniazid and pyrazinamide thrice-weekly for an initial 3 months followed by rifampicin and isoniazid twice-weekly for 6 months. The patients were followed intensively for 2 years from the start of treatment. RESULTS: Of the 108 patients analysed (regimen 1: 56, regimen 2: 52), at the end of treatment clinical status was normal in 91% in regimen 1 and 88% in regimen 2. Of the 91 patients with scan assessments, CT scan lesions disappeared at 24 months in 77% of 47 patients in regimen 1 and 80% of 44 in regimen 2, and in both groups 88% of the patients were clinically normal. None had relapses requiring treatment. CONCLUSIONS: Short-course regimens of 9 months' duration are effective in the treatment of tuberculoma of the brain; clinical recovery was faster than scan clearance.

Adolescent↗
PubMed1994

Jejunal disaccharidases in protein energy malnutrition and recovery.

The jejunal disaccharidases, sucrase, maltase and lactase, were determined in jejunal biopsies obtained from 43 malnourished children and 10 controls. In the study group, 63% were girls and 93% had severe malnutrition. Lactase activity was significantly reduced in third and fourth degree malnutrition (p < 0.05 and p < 0.005, respectively), but maltase activity was significantly reduced only in the fourth degree malnutrition (p < 0.01). After recovery, maltase and sucrase activities showed a marginally significant increase (p = 0.06), where lactase showed no significant increase (p > 0.05). We conclude that jejunal disaccharidase activity decreases significantly with increasing severity of malnutrition, lactase being the most severely affected and the last to recover.

Biopsy↗