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S H Rolbin

Publications and source records attributed to S H Rolbin.

35 records · Page 2Linked to original sources
PubMed1987

A comparison of two types of epidural catheters.

The purpose of this study was to compare two epidural catheters--the Portex epidural catheter and Vas-Cath catheter. One hundred and fifty patients in labour who received epidural anaesthesia were selected and either one or the other catheter was used, based on random assignment. Ease of insertion, maintenance and removal of the catheter were assessed, as was the incidence of blood return and paraesthesiae during epidural catheter insertion. There were no significant differences between the catheters as far as insertion, maintenance and removal were concerned. However, the incidence of paresthesiae was 44 per cent with the Portex and 24 per cent with Vas-Cath catheters (p less than 0.008). The incidence of blood vessel trauma was 12 per cent with the Portex and 6.7 per cent with the Vas-Cath catheter (p = NS). Choice of epidural catheter is a factor to be considered in minimizing the incidence of blood vessel trauma or paresthesiae.

Anesthesia, Epidural↗
PubMed1982

Epidural morphine for analgesia after caesarean section.

A randomized double blind placebo controlled study of the efficacy, duration and safety of epidural morphine for the management of pain after Cesarean section is reported. Three similar groups of patients received either 0, 4 mg or 8 mg of morphine sulphate in 10 ml of normal saline through an epidural catheter at the completion of the operation. Compared to the saline controls, both the 4 mg and 8 mg epidural morphine groups had significant pain relief as judged by an analogue pain scale (p less than 0.001), the time to the first administration of narcotic analgesics (p less than 0.001) and the amount of supplemental analgesic required in the first 36 hours after operation (p less than 0.001). The side effects occurred in a dose-dependent fashion. Two patients who received epidural morphine 8 mg plus additional narcotic or antihistamine had reduced respiratory rates but were easily rousable. Our experience suggests that the epidural administration of morphine 4 mg may be a safe and reliable method of obtaining prolonged analgesia following Caesarean section.

Cesarean Section↗
PubMed1982

Prophylactic intramuscular ephedrine before epidural anaesthesia for caesarean section: efficacy and actions on the fetus and newborn.

The authors studied the effectiveness of ephedrine given intramuscularly before epidural anaesthesia with bupivacaine 0.5 per cent in three groups of patients undergoing elective caesarean section. The patients received intramuscular saline as a placebo, ephedrine 25 mg or ephedrine 50 mg, 15 to 30 minutes before anaesthesia. The incidence of hypotension was 8 to 12 per cent in all three groups. Prophylactic intramuscular ephedrine did not lower the incidence of hypotension significantly. Intramuscular ephedrine 50 mg caused a persistent hypertension in eight out of 12 patients and was associated with an increase in umbilical artery [H+] (decrease in pH). No differences were observed in other indices of neonatal well-being. The prophylactic use of intramuscular ephedrine before epidural anaesthesia for caesarean section is not recommended.

Anesthesia, Epidural↗
PubMed1981

Obstetrical anaesthesia practice in the University of Toronto affiliated hospitals and some randomly selected community hospitals.

A questionnaire was designed to determine the type of personnel that provide obstetrical anaesthesia care and the techniques used in the provision of this care. All seven hospitals with an obstetrical unit affiliated with the University of Toronto and seven community hospitals responded. All anaesthetics were given by physicians. Ninety-two per cent of those in University affiliated hospitals and 63 per cent of those in the community hospitals had obtained their specialty qualification. Standards for preoperative assessment and communication with the patients should be similar to those applied to patients receiving anaesthesia for other reasons. It was clear from our survey that pre-anaesthetic assessment of obstetrical patients differs from that advocated for other surgical patients. For vaginal deliveries, epidural analgesia was clearly the preferred choice, Subarachnoid block was rarely used. The majority of anaesthetists did not use a test dose. Eleven per cent in University-affiliated hospitals and 50 per cent in community hospitals sometimes conducted surgical anaesthesia without tracheal intubation for vaginal delivery. More than 60 per cent routinely encouraged their patients to accept general anaesthesia for Caesarean section. The doctors providing neonatal resuscitation may require further training. Surveys such as this are important if standards of anaesthetic practice are to be established.

Anesthesia, Obstetrical↗
PubMed1981

Effect of lateral position and volume on the spread of epidural anaesthesia in the parturient.

The effect of lateral positioning and the volume of drug injected on the spread of epidural anaesthesia was assessed in 131 healthy parturients. Epidural injection for anaesthesia was done at the L3-4 interspace and a catheter was inserted into the epidural space after injection of the drug. The patients were randomly assigned to four groups. The doses used were 12 ml of bupivacaine 0.25 per cent and 6 ml of bupivacaine 0.5 per cent. Patients were kept in the lateral position in which the block was done (Groups I and III) or turned to the opposite side after completion of the epidural injection (Groups II and IV). Sensory levels and maternal assessment of pain relief were determined fifteen to twenty minutes after injection. All assessments were done by a trained observer who did not know to what group the patient had been allocated. Maintenance of the lateral position after induction of epidural anaesthesia is compatible with satisfactory analgesia for labour. Twelve ml bupivacaine 0.25 per cent provides better analgesia than 6 ml bupivacaine 0.5 per cent although the same mass is injected. The quality of analgesia is improved by turning the patients to the contralateral side after injection of 12 ml bupivacaine 0.25 per cent.

Analgesia↗
PubMed1981

Effect of food on lidocaine kinetics: mechanism of food-related alteration in high intrinsic clearance drug elimination.

The effect of high-protein meal on the hepatic clearance (ClH) of intravenous lidocaine, because of its conceptual importance in understanding first-pass metabolic phenomena, was evaluated in nine healthy males. Our randomized crossover study demonstrated that mean ClH rose from 1245 to 1477 ml/min (P less than 0.03) as a result of the meal (i.e., mean area under the blood concentration-time curve decreased 20%). The magnitude of the change in clearance correlated weakly with fasting ClH (r = 0.54; slope = -0.037% per ml/min; intercept = 67.2%; P less than 0.15). In a separate study, it was observed that the meal did not influence lidocaine serum protein binding; the free fraction of lidocaine in samples drawn from the subjects in the fasting state averaged 0.305 +/- 0.027 while that from subjects who had eaten was 0.321 +/- 0.042. These data suggest that the mean clearance of lidocaine is increased by stimulation of hepatic blood flow rate. Furthermore, the magnitude of this increase is consistent with expectations based on a simple physiologic model. Thus, these data provide experimental support for the hypothesis that transient increases in splanchnic blood flow rate observed after a high-protein meal may explain apparent improvement of the oral bioavailability of model high intrinsic clearance drugs.

Adult↗
PubMed1981

Enflurane analgesia in obstetrics.

The effects of enflurane analgesia (approximately 0.5%) were studied in 55 patients during the second stage of normal vaginal delivery and were compared with effects of nitrous oxide (approximately 40%) in 50 similar patients. The enflurane and oxygen mixture was rated satisfactory by 89% of the mothers and 80% of the anesthesiologists. These ratings did not differ significantly from those for nitrous oxide. Obstetricians, however, rated the enflurane and oxygen mixture superior. The newborns of mothers receiving both agents wee vigorous and comparable when assessed by Apgar scores and cord blood gas tensions. The estimate of blood loss was similar in both groups. Serum inorganic fluoride concentrations in the mother after anesthesia were not significantly increased from preanesthetic levels with either agent. There was no biochemical evidence of renal toxicity. In neonates of mothers given enflurane, the mean umbilical cord concentration of serum inorganic fluoride ions was 2.4 +/- 0.2 micromoles/L, a value well below that associated with nephrotoxicity.

Adult↗
PubMed1981

The effect of maternal administration of ephedrine on fetal heart rate and variability.

Ephedrine is the most popular vasopressor used in obstetrics to prevent or treat spinal or epidural hypotension. Fetal heart rate (FHR) changes during epidural anesthesia were studied in 71 patients; it was found that ephedrine administration (57 patients) was associated with significant increases in FHR and beat-to-beat variability. These changes were dose related and were not associated with fetal asphyxia as judged by measurement of fetal scalp blood pH or Apgar scores.

Anesthesia, Obstetrical↗
PubMed1979

Uterine blood flow and plasma norepinephrine changes during maternal stress in the pregnant ewe.

Because maternal stress may adversely affect the fetus, the authors tested the effects of brief episodes (15-60 sec) of maternal stress in 18 awake pregnant ewes. Maternal agitation and stuggling occurred either following non-painful stimuli such as loud noises or sudden movements of personnel (ten animals) or following the brief application of the ewe's skin of a uniform electrical stimulus of 30 volts with a frequency of 167 Hz for 30-60 sec (eight animals). Stimulation of either type produced a 45-50 per cent increase in mean maternal arterial blood pressure and a concomitant 32-52 per cent decrease in uterine blood flow (P less than 0.05). The decreases in uterine blood flow were brief, lasting less than 3 min, and were not associated with fetal asphyxia. Maternal plasma norepinephrine levels were measured following electrically induced maternal stress and were increased 25 per cent. The authors conclude that maternal stress may decrease uterine blood flow secondary to release of endogenous norepinephrine.

Acid-Base Equilibrium↗
PubMed1979

Dopamine treatment of spinal hypotension decreases uterine blood flow in the pregnant ewe.

In seven pregnant ewes, 3--5 min of hypotension resulting from spinal anesthesia decreased uterine blood flow 17 per cent. Dopamine, in doses sufficient to maintain blood pressure at control values (20--40 micrgram/kg/min) for 3--5 min, further decreased uterine blood flow to 56 per cent less than control and increased uterine vascular resistance to 50 per cent more than control. Following 30 min of hypotension, 30 min of dopamine administration in doses sufficient to restore blood pressure to control values (5--20 microgram/kg/min) similarly decreased uterine blood flow to 29 per cent less than control and increased uterine vascular resistance to 35 per cent more than control.

Anesthesia, Spinal↗
PubMedDate not supplied

Epidural anesthesia for obstetrics after spinal surgery.

The experience of 18 patients with previous spinal surgery who requested epidural anesthesia for obstetric pain was reviewed. Three received epidural anesthetics in two separate pregnancies, producing a total of 21 attempts at epidural anesthesia. All were initiated during labor and three were later extended for Cesarean delivery. Continuous lumbar epidural anesthesia was successfully established in 20 of 21 attempts. Ten were performed easily on the first attempt. There were excessive local anesthetic requirements and/or a patchy block for the remaining 11 attempts. The only complication that could be attributed to the attempts at epidural anesthesia was temporary low back pain in two patients with multiple attempts. No complications were noted on long-term follow-up. Our data, therefore, suggest that epidural anesthesia is safe and generally effective in obstetric patients with previous spinal surgery.

Analgesia, Epidural↗