- Email: [email protected]
Role of platelets and fibrin in the healing sequence. Knighton DR
480
CURRENT LITERATURE
method. Renal function was monitored with tests for serum creatinine concentrations at least three times a week. Audiologic and vestibular examinations were performed on four different occasions: the day of treatment; 7-10 days after treatment; one week after treatment, and two to three months after completion of therapy. Hearing function was tested with a pure-tone audiometer and vestibular function was tested for spontaneous gage and positional nystagmus followed by caloric stimulation with 30°C and 44°C water irrigation. Results with netilmicin alone or in combination with other antibiotics were considered efficacious in 70 out of 74 patients. Of the 77 bacterial specimens cultured, 51 were gram-negative bacilli, 13 were S. UWPUS, and 13 were various strains of streptococci. Elevated serum creatinine concentrations were seen in 17 patients. Six of these patients had underlying renal disease, but in the other 11, netilmicin could have been the cause of impaired renal function. Vestibular findings were abnormal in 12 patients after therapy. Audiologic findings showed that 27 patients had a hearing impairment, but 18 of these had prior impairment before treatment. In none of these 18 patients could any further deterioration of the hearing be found after treatment. In conclusion, the efficacy of netilmicin alone or in combination with other antibiotics was found to be clinically highly effective in a wide range of serious infections with a variety of gram-negative bacteria. The incidence of nephrotoxicity in this study was low, and the rise in serum creatinine was usually slight and in most cases reversible. Ototoxicity was related to the accumulation and the very slow clearance of the drug from inner ear fluids. The absence of sufficiently low trough levels for adequate periods may thus be an important factor of ototoxicity. The study found only one case of netilmicinrelated ototoxicity, and this was a reversible vestibular dysfunction.-ROBERT C. HOBBS Reprint requests to Dr. TjemstrBm: Department of Otolaryngology, Malmb General Hospital, S-21401, Malmii. Sweden. The pharmacokinetics of alfentanil (R39209): opioid analgesic. Bovill JG, et al. Anesthesiology 1982
A new 57:439,
Alfentanil hydrochloride is a new, short-acting opioid analgesic, chemically related to fentanyl, that is undergoing clinical testing. This study discusses the pharmacokinetic properties of alfentanil in humans. Six patients were given 50 p_g/kg. All underwent a variety of surgical procedures. Maintenance fluids were used, and blood loss in excess of 300 ml was replaced. Blood samples were drawn, and alfentanil concentrations were determined by radioimmunoassay. Ninety per cent of the administered dose had left the plasma within 30 minutes. The pharmacokinetics can be described by a three compartment model, with the plasma concentrations after intravenous bolus injection declining triexponentially in a manner similar to fentanyl. The terminal elimination half-life is considerable shorter than that of fentanyl. A continuous analgesic infusion is possible due to its short duration of action.-JOSEPH
E. VAN SICKELS
Reprint requests to Dr. Bovill: Department of Anaesthesia, Academic Hospital, University of Amsterdam, Eerste Helmersstraat 104, 1054 EG Amsterdam, Netherlands.
Role of Platelets and Fibrin in the Healing Knighton DR. Ann Surg 196(4):379, 1982
Sequence.
An orderly progression of healing follows the presence of activated platelets and fibrin at the site of tissue damage. In vivo studies (in rabbit corneas) demonstrated the ability of thrombin-activated platelets to stimulate angiogenesis and increase collagen synthesis. In addition, these experiments showed that fibrin and its degradation products were chemotactic for leukocytes, which subsequently produced neovascularization. Activated platelets produce and release a mitogen, platelet-derived growth factor (PDGF), for fibroblasts and smooth muscle cells. It may be assumed from these findings that in those patients with thrombocytopenia, leukopenia, or clotting disorders, nonhealing wounds might be due to the absence of these mitogenic and chemotactic factors. Transfusion of these blood products to a patient who was deficient in them resulted in wound healing.-VICTOR F. SZYMELA Reprint requests to Dr. Knighton. University of California, San Francisco 839 HSE. San Francisco. CA 94143.
Rhinometry: Measurement of Nasal Patency. JT. Ann Allergy 49(4):--, 1982
Connell
Rhinometry is the measurement of nasal airflow and therefore provides an assessment of nasal patency. The authors describe a method of rhinometry using simple devices applied externally to the nostrils. Transducers placed in one nostril measure the pressure, while those in the other measure the air speed. The nasal patency (resistance) is obtained by dividing the change in pressure (API, measured in centimeters of HzO, by volume (V’), measured in liters per second. This method is less expensive and less complex than other methods. It can be applied clinically to patient assessment in the clinician’s office before and after surgery. Other methods of measurement are discussed along with their disadvantages.VICTOR R. SZYMELA Reprint requests to Dr. Connell: Nasal Diseases Study Center, Holy Name Hospital, Teaneck, NJ 07666.
Influence of Oral Atropine or Hyoscine on the Absorption of Oral Diazepam. Gregoretti SM, Uges DRA. Br J Anesth 54(11):1231, 1982 This article studied the influence of oral atropine on the absorption of oral diazepam. Both drugs were administered at the same time to eight volunteers. Using a threeway crossover randomized double-blind design, the effects of combining anticholinergic premeditation with oral diazepam were assessed. No difference was found in the timing or the amount of sedation between diazepam used alone or in combination with atropine. The serum diazepam concentrations were not significantly different after any of the three test regimens. It is concluded from this study that when the use of an anticholinergic in premedication is desirable, atropine can be administered orally with diazepam without a delay or reduction in its effect.-CHARLES L. RINCGOLD Reprint requests to Drs. Gregoretti and Uges: Department of Anaesthesia, St. Radbound-Ziekenhuis, Catholic University, 6500 H B Nijmegen, The Netherlands.
CURRENT LITERATURE
method. Renal function was monitored with tests for serum creatinine concentrations at least three times a week. Audiologic and vestibular examinations were performed on four different occasions: the day of treatment; 7-10 days after treatment; one week after treatment, and two to three months after completion of therapy. Hearing function was tested with a pure-tone audiometer and vestibular function was tested for spontaneous gage and positional nystagmus followed by caloric stimulation with 30°C and 44°C water irrigation. Results with netilmicin alone or in combination with other antibiotics were considered efficacious in 70 out of 74 patients. Of the 77 bacterial specimens cultured, 51 were gram-negative bacilli, 13 were S. UWPUS, and 13 were various strains of streptococci. Elevated serum creatinine concentrations were seen in 17 patients. Six of these patients had underlying renal disease, but in the other 11, netilmicin could have been the cause of impaired renal function. Vestibular findings were abnormal in 12 patients after therapy. Audiologic findings showed that 27 patients had a hearing impairment, but 18 of these had prior impairment before treatment. In none of these 18 patients could any further deterioration of the hearing be found after treatment. In conclusion, the efficacy of netilmicin alone or in combination with other antibiotics was found to be clinically highly effective in a wide range of serious infections with a variety of gram-negative bacteria. The incidence of nephrotoxicity in this study was low, and the rise in serum creatinine was usually slight and in most cases reversible. Ototoxicity was related to the accumulation and the very slow clearance of the drug from inner ear fluids. The absence of sufficiently low trough levels for adequate periods may thus be an important factor of ototoxicity. The study found only one case of netilmicinrelated ototoxicity, and this was a reversible vestibular dysfunction.-ROBERT C. HOBBS Reprint requests to Dr. TjemstrBm: Department of Otolaryngology, Malmb General Hospital, S-21401, Malmii. Sweden. The pharmacokinetics of alfentanil (R39209): opioid analgesic. Bovill JG, et al. Anesthesiology 1982
A new 57:439,
Alfentanil hydrochloride is a new, short-acting opioid analgesic, chemically related to fentanyl, that is undergoing clinical testing. This study discusses the pharmacokinetic properties of alfentanil in humans. Six patients were given 50 p_g/kg. All underwent a variety of surgical procedures. Maintenance fluids were used, and blood loss in excess of 300 ml was replaced. Blood samples were drawn, and alfentanil concentrations were determined by radioimmunoassay. Ninety per cent of the administered dose had left the plasma within 30 minutes. The pharmacokinetics can be described by a three compartment model, with the plasma concentrations after intravenous bolus injection declining triexponentially in a manner similar to fentanyl. The terminal elimination half-life is considerable shorter than that of fentanyl. A continuous analgesic infusion is possible due to its short duration of action.-JOSEPH
E. VAN SICKELS
Reprint requests to Dr. Bovill: Department of Anaesthesia, Academic Hospital, University of Amsterdam, Eerste Helmersstraat 104, 1054 EG Amsterdam, Netherlands.
Role of Platelets and Fibrin in the Healing Knighton DR. Ann Surg 196(4):379, 1982
Sequence.
An orderly progression of healing follows the presence of activated platelets and fibrin at the site of tissue damage. In vivo studies (in rabbit corneas) demonstrated the ability of thrombin-activated platelets to stimulate angiogenesis and increase collagen synthesis. In addition, these experiments showed that fibrin and its degradation products were chemotactic for leukocytes, which subsequently produced neovascularization. Activated platelets produce and release a mitogen, platelet-derived growth factor (PDGF), for fibroblasts and smooth muscle cells. It may be assumed from these findings that in those patients with thrombocytopenia, leukopenia, or clotting disorders, nonhealing wounds might be due to the absence of these mitogenic and chemotactic factors. Transfusion of these blood products to a patient who was deficient in them resulted in wound healing.-VICTOR F. SZYMELA Reprint requests to Dr. Knighton. University of California, San Francisco 839 HSE. San Francisco. CA 94143.
Rhinometry: Measurement of Nasal Patency. JT. Ann Allergy 49(4):--, 1982
Connell
Rhinometry is the measurement of nasal airflow and therefore provides an assessment of nasal patency. The authors describe a method of rhinometry using simple devices applied externally to the nostrils. Transducers placed in one nostril measure the pressure, while those in the other measure the air speed. The nasal patency (resistance) is obtained by dividing the change in pressure (API, measured in centimeters of HzO, by volume (V’), measured in liters per second. This method is less expensive and less complex than other methods. It can be applied clinically to patient assessment in the clinician’s office before and after surgery. Other methods of measurement are discussed along with their disadvantages.VICTOR R. SZYMELA Reprint requests to Dr. Connell: Nasal Diseases Study Center, Holy Name Hospital, Teaneck, NJ 07666.
Influence of Oral Atropine or Hyoscine on the Absorption of Oral Diazepam. Gregoretti SM, Uges DRA. Br J Anesth 54(11):1231, 1982 This article studied the influence of oral atropine on the absorption of oral diazepam. Both drugs were administered at the same time to eight volunteers. Using a threeway crossover randomized double-blind design, the effects of combining anticholinergic premeditation with oral diazepam were assessed. No difference was found in the timing or the amount of sedation between diazepam used alone or in combination with atropine. The serum diazepam concentrations were not significantly different after any of the three test regimens. It is concluded from this study that when the use of an anticholinergic in premedication is desirable, atropine can be administered orally with diazepam without a delay or reduction in its effect.-CHARLES L. RINCGOLD Reprint requests to Drs. Gregoretti and Uges: Department of Anaesthesia, St. Radbound-Ziekenhuis, Catholic University, 6500 H B Nijmegen, The Netherlands.