An audit of the safety of an acute pain service

We audited and analysed the adverse effects and safety of postoperative pain management on 2509 consecutive patients under care of the Acute Pain Service at a tertiary referral teaching hospital over a 32-month period. Our standard respiratory monitoring consisted of continuous pulse oximetry, hourly respiratory rate counting, sedation scoring and intermittent arterial blood gas sampling. This protocol was reliable and detected six episodes of bradypnoea, 13 of hypercapnia and 23 of oxygen desaturation occurring in 39 patients (1.8% of all spontaneously breathing patients) . Two patients required naloxone injection and none had long-term sequelae. Hypotension due to epidural bupivacaine 0.0625% and fentanyl 3.3 μg.ml⁻¹ infusion occurred in four patients (1.2%), all with a sensory block higher than T₅. They readily responded to fluid infusion and ephedrine (two patients). Postoperative nausea or vomiting occurred in 723 (28.8%) and 380 (15.1%) patients, respectively. Odds ratio analysis showed that the risk factors for postoperative nausea and vomiting were: female gender, gynaecological operations, nongeriatric patients and systemic analgesia. Postoperative nausea and vomiting decreased analgesic efficacy by discouraging the use of patient-controlled analgesia and was regarded as equally distressing as pain. Other side-effects included: pruritus in 182 patients; dizziness in 333 and lower limb weakness in 73 (21.2% of patients receiving epidural local anaesthetics). It is concluded that a standard monitoring and management protocol, an experienced nursing team and reliable Acute Pain Service coverage is mandatory for the safe use of modern analgesic techniques.     

Insulin-like immunoreactivity persists in the spinal cord of streptozotocin-induced diabetic rats.

In both saline-injected control and streptozotocin-induced diabetic rats, insulin-like immunoreactivity was localized in the cervical, thoracic, lumbar and sacral segments of the spinal cord. This insulin-like immunoreactivity was consistently localized in the neurons and dendrites from control rats as well as from diabetic rats ranging from 1 month to 12 months after diabetes induction. In the neuronal cell bodies, the reaction product was predominantly localized in the cell nucleus and the proximal and distal dendrites. In the labelled cell nucleus, the reaction product was scattered throughout the cell cytoplasm and nucleoplasm, but not within the nucleolus. The inner and outer nuclear membranes were also labelled. In labelled dendrites, the reaction product was closely associated with the parallel arrays of neurotubules, plasma membranes and synaptic densities. Most of the labelled distal dendrites were postsynaptic to unlabelled axon terminals. A labelled dendrite often formed the central element of a synaptic glomerulus with several unlabelled axon terminals. It is hereby hypothesized that some of the neurons in the spinal cord of the diabetic rat are capable of synthesizing insulin-like substance(s), which appears to be involved in neurotransmission and neuromodulation.     

Effect of tissue inhomogeneity on beta dose distribution of 32P

In a homogeneous medium of soft tissue the radiation dose distribution due to a nonuniformly distributed beta source can be calculated by convolution of the beta dose point kernel of the nuclide with the source distribution. A possible extension of the technique to the calculation of the dose distribution in heterogeneous media involving relatively simple geometric interfaces requires the knowledge of the resulting perturbation to the beta point kernels in individual media. We simulated a soft-tissue-bone planar interface by a polystyrene (PST)-aluminum junction and measured the change in beta dose from the dose value in homogeneous PST due to a point source of 32P using 7LiF thermoluminescent dosimeters. With the point source at the interface, the dose rates at 0-31, 125-156, and 283-314 mg/cm2 separations from the interface were increased by (12 +/- 3)%, (8 +/- 2)%, and (3 +/- 2)%, respectively, compared with homogeneous PST. With the point source at a PST-air planar interface to simulate a soft-tissue-air junction, the dose rates at 0-31, 139-170, and 283-314 mg/cm2 from the interface were decreased by (25 +/- 4)%, (11 +/- 7)%, and (5 +/- 2)%, respectively. The changes in dose rates for these two interfaces have also been measured with degraded spectra of 32P. Comparison of the experimental data with Monte Carlo calculation for a point source and the two-group method of calculation for a plane source is also presented.     

Surgical resection for metastatic melanoma to the lung

From 1971 through December 1986, the courses of 47 patients who underwent thoracotomy for pulmonary metastases from melanoma were retrospectively reviewed to determine the efficacy of this approach in the management of selected patients with melanoma. The overall five-year survival rate was 25% (median survival, 19 months). Thirty-eight patients were free of disease following thoracotomy. These patients fared significantly better than those who had residual disease following thoracotomy, with a five-year survival rate of 31% (median survival, 24 months) compared with 0% (median survival, six months). Survival was not influenced by the addition of adjuvant therapy or duration of time before the development of metastases (less than 12 months vs greater than or equal to 12 months). In selected patients with melanoma metastatic to the lung, thoracotomy with complete excision of the metastatic deposits results in improved survival and should be considered the treatment of choice.     

Aspiration cytology in the management of breast lesions

In a group of patients with breast lumps, diagnosis made by pre-operative aspiration cytology was compared with that obtained by histological section of excised specimens. Results showed that aspiration cytology correctly diagnosed 89% of malignant lesions and 92.6% of benign lesions based upon histological diagnosis. Cytological diagnosis of benign disease had a false negative rate of 6% while cytological diagnosis of malignant disease had a 2.7% false positive rate. Only 3.5% of cytologies returned an inadequate diagnosis. This study shows that aspiration cytology should be useful in allowing a better psychological preparation of patients before surgery as well as better utilization of operation theatre facilities.     

Acute pancreatitis in the aged

Forty-seven patients aged more than 75 years with acute pancreatitis were studied. The most common cause of acute pancreatitis was biliary tract stones. The clinical presentation and severity of the disease as judged by the number of poor prognostic factors were not different from the group of patients aged less than 75 years. The mortality rate in the older group was thrice that of the younger group (21.3% versus 7.24%). The higher mortality rate was explained by a higher incidence of deaths related to complications of biliary stones and coincidental diseases. Significantly more aged patients with mild disease died, indicating the limitation of predictive ability of the scoring system in acute pancreatitis of the aged.     

Influence of age on the mortality from acute pancreatitis

The influence of age on the mortality rate of 268 patients with acute pancreatitis was studied. The hospital mortality rate for patients aged below 50 years was 5.9 per cent. The figure increased to 21.3 per cent in patients aged over 75; the high mortality was accounted for by a higher incidence of deaths related to concomitant medical or surgical diseases in the same hospital admission rather than to complications resulting directly from the pathological process of acute pancreatitis. When only deaths due to complications of acute pancreatitis were analysed, the mortality rate was not significantly different between the young and elderly groups. Moreover, the complication rate and the proportion of patients having severe disease (judged by the number of prognostic signs) were not higher in the elderly. Thus acute pancreatitis was intrinsically not more serious were it not for the presence of concomitant diseases with advanced age.     

Is dietary counselling effective in increasing dietary calcium,protein and energy intake in patients with osteoporotic fractures? A randomized controlled clinical trial

To determine the feasibility of increasing the calcium, protein and calorie intake of osteoporotic fracture patients by repeated dietary counselling delivered by a dietitian, a randomized controlled trial was conducted. Among 189 patients presenting with osteoporotic fractures to an Orthopaedics and Traumatology Department of a large regional hospital, 98 patients were randomized to the intervention group and 91 were randomized to the control group (with usual care). Intervention group received three sessions of dietary counselling with tailored made recommendations over a period of 4 months, while the control group only received dietary assessment and pamphlets on the prevention of osteoporosis. Almost all subjects in both intervention and control groups had calcium intake below the recommended level of 1000 mg at baseline. Half and 60% of subjects in both groups had total energy and protein intake below recommended levels respectively. The mean weights of control and intervention groups at baseline were 51.5 and 50.9 kg respectively, while the body mass index (BMI) were 22.6 (kg m(-2)) and 22.6 (kg m(-2)) respectively. After dietary intervention, significant increase of intake was seen in calcium intake (P = 0.0095 by t-test) in the intervention group. No significant increase was seen in protein or calorie intake. No significant change was observed in the body weight or BMI although there was a positive trend in the intervention group for all these parameters. We concluded that there was general malnutrition in Chinese elderly who presented with osteoporotic fractures. Dietary calcium could be increased by repeated professional dietary counselling. Future studies with longer duration and more objective clinical outcomes will be helpful to further demonstrate the long-term effects of dietary intervention on osteoporosis and other chronic diseases.