PubMed HealthSearch

Biomedical subjects

W R Camann

Publications and source records attributed to W R Camann.

15 recordsLinked to original sources

Does epidural administration of butorphanol offer any clinical advantage over the intravenous route? A double-blind, placebo-controlled trial.

The differential effects of intravenous versus epidural administration of short-acting, lipid-soluble opioids is controversial. This study was undertaken to compare these two routes of administration using the mixed agonist-antagonist opioid, butorphanol. Forty-five women undergoing elective cesarean delivery at term under epidural lidocaine anesthesia were randomized to receive a single bolus of either epidural or intravenous butorphanol 2 mg or saline control for postoperative analgesia. At precisely 60 min after the last dose of epidural local anesthetic, all patients received a simultaneous epidural and intravenous injection in a randomized, double-blinded fashion. The intravenous group received butorphanol intravenous and saline epidurally; the epidural group received saline intravenous and butorphanol epidurally; and a control group received saline via both routes. When additional analgesia was requested, all patients received patient-controlled analgesia (PCA) with intravenous morphine (2-mg demand dose, 7-min lockout interval). Analgesia was quantitated using a visual analogue scale and subsequent PCA morphine requirements. The interval from study drug injection until first request for PCA use was equivalent for the intravenous and epidural groups (89 +/- 9 and 83 +/- 8 min, respectively) and significantly longer than in control group (39 +/- 4 min, P less than 0.001, intravenous and epidural vs. control). Analgesia was equivalent in the intravenous and epidural groups at all observation points, and pain scores were significantly lower than control for the first 120 min after study drug injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

A comparison of intrathecal, epidural, and intravenous sufentanil for labor analgesia.

A number of recent studies have suggested that the analgesic effects of highly lipid-soluble opioids are similar when these agents are administered either epidurally or intravenously. We sought to test whether the lipid-soluble opioid sufentanil was more effective when administered intrathecally than when administered epidurally or intravenously. Twenty-four women during active labor received sufentanil 10 micrograms either intrathecally (n = 9), epidurally (n = 8), or intravenously (n = 7), using a combined spinal-epidural technique. The sufentanil was administered alone, without concomitant local anesthetics. Analgesia was assessed using the visual analogue score as well as the time elapsed from the administration of study drug to the patient's request for additional analgesia via the epidural catheter (bupivacaine 0.25%). The median duration of analgesia (median, interquartile range) was 84 (70-92) min in the intrathecal group, 30 (23-32) min in the epidural group, and 34 (17-30) min in the intravenous group (P < 0.001). The intrathecal group showed rapid and significant decrease in visual analogue scale scores, whereas visual analogue scale scores in the other two groups did not decrease and remained significantly elevated compared to those of the intrathecal group at all observation points. Side effects were limited to pruritus in 3 patients (2 moderate and 1 severe) in the intrathecal group. No patient developed post-dural puncture headache. We conclude that sufentanil 10 micrograms intrathecally provides rapid and effective analgesia of 1-2-h duration during labor. Epidural and intravenous use of this dose of sufentanil did not provide evidence of satisfactory analgesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Epidural nalbuphine for analgesia following caesarean delivery: dose-response and effect of local anaesthetic choice.

The analgesic profile of epidural nalbuphine for postoperative pain relief and the impact of local anaesthetic choice upon this profile was investigated in 58 patients undergoing elective Caesarean delivery under epidural anaesthesia. Patients were randomized to receive either lidocaine 2% with 1:200,000 epinephrine or 2-chloroprocaine 3% for perioperative anaesthesia, followed by either 10, 20, or 30 mg of epidural nalbuphine administered at the first complaint of postoperative discomfort. Postoperative analgesia was quantitated on a visual analogue (VAS) scale, and by the time from the epidural opioid injection until the first request for supplemental pain medication. The duration of analgesia after lidocaine anaesthesia followed by 10, 20 or 30 mg nalbuphine was 77 (53-127) min, 205 (110-269) min, and 185 (116-241), respectively (median, 95% confidence interval, P less than 0.01, 20 and 30 mg vs 10 mg). Following 2-chloroprocaine anaesthesia, VAS remained consistently elevated: the median duration of analgesia was only 30-40 min and did not differ among the three doses of nalbuphine. Side-effects consisted only of somnolence, and were noted only following lidocaine anaesthesia. Somnolence was observed in 0, 20% and 50% of those receiving 10 mg, 20 mg and 30 mg of nalbuphine respectively (NS). No evidence of respiratory depression was noted in any patient. It is concluded that 20 or 30 mg of epidural nalbuphine provides analgesia for only two to four hours following Caesarean delivery with lidocaine anaesthesia, but anaesthesia with 2-chloroprocaine resulted in minimal or no analgesia from this opioid. Nalbuphine appears to be a disappointing agent for epidural use after Caesarean delivery.

Adult

Red cell use during cesarean delivery.

The transfusion of red cells (RBCs) was analyzed over a 4-year period (1984-1987), during which 9596 cesarean deliveries were performed. A total of 336 patients were identified as receiving RBC transfusions during or after cesarean delivery; 747 units of RBCs were administered. The overall incidence of transfusion in this patient population declined from 6.2 to 3.2 percent during the study period (p less than 0.001). Slightly more than one-half (54.4%) of all transfusions were given in the operating room or recovery room. The majority of patients (68.4%) received 2 units of RBCs, 11.6 percent received a 1-unit transfusion, and 8.3 percent received 5 units or more. The most common obstetric diagnoses associated with RBC transfusion were disorders of placental implantation, preeclampsia, premature labor with tocolytic therapy, fetal distress, and augmentation of dysfunctional labor. In patients without risk factors for bleeding, there was no trend indicating increased transfusion requirements when general anesthesia was employed. In conclusion, this study documents a decline in the transfusion rate during cesarean delivery.

Anesthesia, Epidural

Maternal temperature regulation during extradural analgesia for labour.

We have studied the effect of analgesia on maternal temperature (oral and tympanic membrane) progression in 53 women during normal spontaneous labour. Three groups were studied: two received extradural analgesia with a continuous infusion of 0.25% bupivacaine with or without the addition of fentanyl; the third group received only parenteral opioid analgesia. All patients were afebrile and without clinical evidence of infection at the beginning of the study. Both groups of patients receiving extradural analgesia had a consistent and significant increase in temperature after approximately 5 h of analgesia; no such trend was observed in the parenteral opioid group. Alterations in mechanisms of heat dissipation may explain these findings.

Adolescent

Chloroprocaine antagonism of epidural opioid analgesia: a receptor-specific phenomenon?

Sixty healthy patients scheduled for elective cesarean delivery under epidural anesthesia were randomized to receive either lidocaine or 2-chloroprocaine as the primary local anesthetic agent. When patients first complained of postoperative pain in the recovery room, they were given either fentanyl 50 micrograms or butorphanol 2 mg, epidurally, in a randomized, blinded fashion. Postoperative analgesia, quantitated on a visual analogue scale, as well as time elapsed until first request for supplemental opioid, did not differ for patients receiving butorphanol after either 2-chloroprocaine or lidocaine anesthesia. In contrast, epidural fentanyl produced a shorter and lesser degree of sensory analgesia after 2-chloroprocaine use, whereas epidural fentanyl after lidocaine anesthesia provided pain relief similar to that seen in the butorphanol groups. Side effects were limited to somnolence with butorphanol and pruritus with fentanyl. No evidence of respiratory depression was seen in any patient. We conclude that 2 mg of butorphanol epidurally provides approximately 2 to 3 h of effective analgesia after cesarean delivery with either lidocaine or 2-chloroprocaine anesthesia. Epidural fentanyl seems to be antagonized when 2-chloroprocaine, but not lidocaine, is used as the primary local anesthetic agent. We suggest a possible mu-receptor-specific etiology for this effect.

Adult

Effects of oral caffeine on postdural puncture headache. A double-blind, placebo-controlled trial.

Forty postpartum patients with postdural puncture headache (PDPH) were randomly assigned to receive oral caffeine (300 mg) or a placebo. Intensity of headache, quantitated using a visual analogue pain scale (VAS), was assessed immediately before drug administration and 4 and 24 h later. Relief of PDPH measured as delta VAS (initial VAS - VAS at 4 h) was significantly better in the caffeine than in the placebo group (P = 0.014). Six patients (30%) whose PDPH was relieved by caffeine at 4 h had recurrence of symptoms the following day. Our study demonstrates that caffeine administered orally provides relief, albeit if sometimes transient, from PDPH with minimal side effects.

Administration, Oral

Reoperation for coronary artery bypass grafting: anesthetic challenge.

The problem of caring for patients undergoing reoperative coronary revascularization is one that cardiac anesthesiologists will face with increasing frequency. Many thousands of CABG procedures continue to be performed annually with ever-increasing survival rates. Consequently, the population at risk for reoperative CABG is growing, while surgical intervention necessarily follows apace. As one recent long-term, retrospective study showed, patients surviving 12 years after CABG have a reoperative rate of 17.3%. Physicians caring for these patients must recognize that they are not seeing patients with routine CAD, but with a different entity: coronary graft disease (CGD). These patients with CGD are different in many ways from those with native CAD, and these differences must be taken into account when planning for their perioperative care. Cardiologists have strived to check the growth of CGD by aggressive emphasis on modification of coronary risk factors such as tobacco use, hypertension, and hyperlipidemia. In addition, recent interest has been focused on a pharmacologic approach via the platelet-prostaglandin system. Surgeons have also attempted to reduce the incidence of CGD by recognition that significantly improved long-term patency rates can be achieved by the use of the internal thoracic artery as a bypass conduit. Consequently, an expanded role for this vessel in the form of free, sequential, and bilateral ITA grafting is currently being advocated as a surgical solution to the problem of CGD. In contrast, the anesthesiologist probably has little to add to the prevention of CGD, but may be able to contribute to a favorable outcome at reoperation. The medical variables and preoperative characteristics that make reoperative CABG patients different from those presenting for primary CABG should be recognized. A firm appreciation of the nature of graft disease, as well as the surgical intricacies required for correction, can only serve to improve the care offered during these often complex operations. Aggressive, invasive hemodynamic monitoring, constant vigilance for signs of early ischemia, and preparedness for prebypass hemorrhage and postbypass ventricular dysfunction should be made. Furthermore, if anesthesiologists are to contribute to an improved outcome in these patients, strategies must be developed to attenuate cerebral and myocardial damage resulting from hemorrhage and atheroembolic catastrophies that appear to be frequent complications in these challenging surgical patients.

Anesthesia, General

Anesthesia for cesarean delivery in patients with herpes simplex virus type-2 infections.

Some concerns exist regarding the use of regional anesthesia for patients with active genital herpes simplex virus type-2 (HSV) infections undergoing cesarean delivery. Previous studies have reported the safe use of epidural anesthesia in these patients; there are no reports of the use of spinal anesthesia in this setting. We performed a 6-year retrospective survey of 169 patients delivered by cesarean delivery because of HSV infection. One hundred sixty-four of these patients had the diagnosis of secondary infection and five had the diagnosis of primary infection. Fifty-nine patients received general anesthesia, 75 received spinal anesthesia, and 35 received epidural anesthesia. One patient who was diagnosed with primary herpes and who received spinal anesthesia had a transient postpartum neurologic deficit; the etiology of this deficit was not clearly related to the anesthetic technique. No patients with secondary infection had septic or neurologic complications related to the anesthetic. Both spinal and epidural anesthesia appear to be safe alternatives for patients with secondary HSV infections undergoing cesarean delivery.

Anesthesia, Epidural

Anesthetic management of a parturient with myotonia dystrophica: a case report.

We report the case of a 22-year-old parturient with myotonia dystrophica. She underwent two separate intraabdominal surgical procedures in one day, both under lumbar epidural anaesthesia. Management was directed toward prevention of shivering, a known trigger of myotonic crises. Measures used included warm ambient atmosphere, warmed IV fluids, warming blankets and administration of epidural sufentanil, an opioid recently ascribed as an inhibitor of shivering in parturients.

Abdomen