Effect of doxapram on the respiratory rhythmical discharge activity in the brainstem slice of neonatal rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of doxapram on the respiratory rhythmical discharge activity (RRDA) in the brainstem slices of neonatal rats.</p><p><b>METHODS</b>Thirty neonatal SD rats (of either sex, 0-3 days old) were randomly divided into 6 equal groups (groups I-VI), and the brainstem slices which contained the medial region of the nucleus retrofacialis (mNRF) were prepared. All the slices were perfused with modified Kreb's solution (MKS), and in group I (control group), the slices were perfused with MKS only; in groups II to IV, the slices were perfused with doxapram in MKS continuously at the concentrations of 2, 5, and 10 micromol/L, respectively; in groups V and VI, the slices were perfused with 20 micromol/L propofol and 20 micromol/L propofol plus 5 micromol/L doxapram, respectively. The RRDA in the hypoglossal nerve was recorded by suction electrode. The discharge time course of the inspiratory (TI), expiratory (TE), respiratory cycle (RC) and integral amplitude of the inspiratory discharge (IA) were recorded at 1, 3, 5, 10, 15, and 30 min after the application of the drugs.</p><p><b>RESULTS</b>The hypoglossal nerve in groups I, II and VI showed no significant changes of RRDA in the entire course of the experiment (P>0.05). In groups III and IV, the TI, IA increased and TE decreased significantly 5 min after doxapram application (P<0.05), and the RC was shortened only at 10 min. In group V, the TI and IA decreased and the RC and TE increased significantly after the drug application (P<0.05).</p><p><b>CONCLUSION</b>Doxapram (>5 micromol/L ) can directly stimulate the RRDA and prevent propofol-induced inhibitory effects in the brainstem slice of neonatal rats, and the effects are mediated by its actions upon the inspiratory neurons in the mNRF.</p>

Negative-pressure Pulmonary Edema by Doxapram-induced Larygospasm: A case report / 대한마취과학회지

Doxapram is a peripheral and central respiratory stimulant, producing an increase in tidal volume and a slight increase in respiratory rate. It can temporarily overcome drug-induced respiratory and central nervous system depression, including that seen immediately postoperatively. However, it can also cause side effects, including laryngospasm and vomiting postoperatively. Doxapram-induced laryngospasm causes the increased respiratory efforts to induce more negative pleural pressure, thus causing a negative-pressure pulmonary edema.Therefore, doxapram should not be used if signs of upper airway obstruction are present.

The Effect of Doxapram Hydrochloride on Bispectral (BIS) Index and Recovery from Desflurane Inhalational Anesthesia / 대한마취과학회지

BACKGROUND: Doxapram hydrochloride is a respiratory stimulant that produces arousal effects in patients under anesthesia. We investigated the effects of doxapram on the recovery time and BIS index of patients administered desflurane inhalational anesthesia. METHODS: 40 patients who underwent general anesthesia using desflurane that had an ASA physical status of I or II received either 1 mg/kg of doxapram hydrochloride (doxapram group, n = 20) or normal saline (control group, n = 20) IV at end of surgery. Anesthetic recovery after the injection of doxapram was then determined based on the time to eye opening in response to verbal command, hand squeezing on command, time to extubation, and Aldrete recovery score. BIS index, systolic blood pressure, tidal volume and heart rate were recorded every minute for up to thirteen minutes. RESULTS: The doxapram group showed significantly shorter times to emergence based on eye opening in response verbal command (sec) (409 +/- 114 vs 320 +/- 116), hand squeezing on command (sec) (458 +/- 119 vs 351 +/- 114) and extubation (sec) (491 +/- 103 vs 418 +/- 79) compared to control group. The BIS score was not significantly different between the two groups. CONCLUSIONS: The Bis index was not significant higher in the doxapram group, with the exception of the measurement recorded at 2 minutes, however the recovery time from desflurane inhalational anesthesia was faster in the doxapram group than the control group.

Effect of daxapram on recovery following total intravenous anesthesia with propofol and remifentanil / 대한마취과학회지

BACKGROUND: The aim of this study was to investigate the effect of doxapram on recovery following propofol-remifentanil anesthesia. METHODS: Forty patients scheduled for gastrectomy were randomly allocated to receive either doxapram 1 mg/kg or normal saline at the end of surgery under propofol-remifentanil anesthesia. Clinical recovery from anesthesia was assessed by times to spontaneous breathing, eye opening on verbal command, extubation, and discharge from the postanesthetic care unit (PACU). Bispectral index (BIS) values, blood pressure, and heart rate were recorded every 2 min for 16 min after the administration of doxapram or saline. The incidences of side effects were checked in the recovery room. RESULTS: Spontaneous breathing was recovered after 6.2 +/- 1.1 minutes in the Doxapram group versus 9.2 +/- 1.8 minutes in the normal saline group (P < 0.001). Times to eye and extubation were also shorter in the Doxapram patients than in the normal saline patients (6.9 +/- 1.0 and 8.1 +/- 1.7 min versus 10.4 +/- 2.0 and 12.0 +/- 2.6 min, respectively) (P < 0.001). However, the times to PACU discharge were not different between the two groups (46.9 +/- 4.9 min versus 47.0 +/- 6.0 min, respectively). The patients in the Doxapram group showed higher mean BIS values compared with the normal saline group during emergence, but there were no differences in arterial blood pressure, heart rate and incidences of side effects between the two groups. CONCLUSIONS: Doxapram 1 mg/kg hastens early recovery from TIVA with propofol and remifentanil, and this emergence effect correlates with higher BIS values. Doxapram, however, does not affect the discharge time from the PACU and incidences of side effects.

Effect of daxapram on recovery following total intravenous anesthesia with propofol and remifentanil / 대한마취과학회지

BACKGROUND: The aim of this study was to investigate the effect of doxapram on recovery following propofol-remifentanil anesthesia. METHODS: Forty patients scheduled for gastrectomy were randomly allocated to receive either doxapram 1 mg/kg or normal saline at the end of surgery under propofol-remifentanil anesthesia. Clinical recovery from anesthesia was assessed by times to spontaneous breathing, eye opening on verbal command, extubation, and discharge from the postanesthetic care unit (PACU). Bispectral index (BIS) values, blood pressure, and heart rate were recorded every 2 min for 16 min after the administration of doxapram or saline. The incidences of side effects were checked in the recovery room. RESULTS: Spontaneous breathing was recovered after 6.2 +/- 1.1 minutes in the Doxapram group versus 9.2 +/- 1.8 minutes in the normal saline group (P < 0.001). Times to eye and extubation were also shorter in the Doxapram patients than in the normal saline patients (6.9 +/- 1.0 and 8.1 +/- 1.7 min versus 10.4 +/- 2.0 and 12.0 +/- 2.6 min, respectively) (P < 0.001). However, the times to PACU discharge were not different between the two groups (46.9 +/- 4.9 min versus 47.0 +/- 6.0 min, respectively). The patients in the Doxapram group showed higher mean BIS values compared with the normal saline group during emergence, but there were no differences in arterial blood pressure, heart rate and incidences of side effects between the two groups. CONCLUSIONS: Doxapram 1 mg/kg hastens early recovery from TIVA with propofol and remifentanil, and this emergence effect correlates with higher BIS values. Doxapram, however, does not affect the discharge time from the PACU and incidences of side effects.

The Effect of Doxapram Hydrochloride on the Ventilation Responses during Total Intravenous Anesthesia by Laryngeal Mask Airway / 대한마취과학회지

BACKGROUND: Intravenous anesthetics causes depression of ventilatory response to hypercapnea. Doxapram stimulates ventilation via peripheral and central chemoreceptors. This study was aimed to evaluate the effect of doxapram on ventilation during total intravenous anesthesia (TIVA). METHODS: 60 patients undergoing operation under spontaneous ventilation via laryngeal mask airwaywere randomly divided into 3 groups: Control group received 5% dextrous infusion, D-2 group received doxapram injection of 1 mg/kg followed by continuous infusion of 2 mg/kg/hr, and D-4 group received doxapram injection of 2 mg/kg followed by continuous infusion of 4 mg/kg/hr. Anesthesia was induced and maintained with propofol and remifentanil. Respiratory rate, tidal volume (VT) and arterial carbon dioxide tension (PaCO2) were measured before and 15 min after induction of anesthesia, 0(15 min after start of operation), 1, 2, 3, 5, 15, 30, 45, and 60 min after start of doxapram infusion during TIVA. RESULTS: VT was significantly increased 1 min after start of doxapram infusion and returned to the value of pre-doxapram infusion immediately. In D-4 group, VT was significantly (P < 0.05) increased again 5 min after doxapram infusion compared with the value of pre-doxapram infusion and control group. PaCO2 was decreased 1 min after start of doxapram infusion and then increased again 2 min after doxapram infusion. In D-4 group, the degree of increase of PaCO2 was significantly (P < 0.05) less than those of D-2 group. CONCLUSIONS: Doxapram injection of 2 mg/kg followed by continuous infusion of 4 mg/kg/hr improved the depression of ventilatory response during TIVA.

Clinical observation of target-controlled remifentanil infusion combined with propofol and doxapram in painless artificial abortion / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the impacts of doxapram on anesthetic efficacy and respiratory and circulatory functions during anesthesia with remifentanil given by target-controlled infusion (TCI) combined with propofol in painless artificial abortion.</p><p><b>METHODS</b>A total of 120 ASA I women requiring voluntarily painless artificial abortion were randomized into two equal groups. One group was given remifentanil by TCI at 2 ng/ml and propofol 1mg/kg (group I), and the other given remifentanil by TCI, propofol, and doxapram 0.6 mg/kg (group II). The anesthetic efficacy and respiratory and circulatory suppression during anesthesia were observed.</p><p><b>RESULTS</b>Both of the two groups showed satisfactory anesthetic efficacy with comparable the BIS values (P>0.05). No significant difference was noted in the induction time and awaking time between the two groups (P>0.05), but group I had more serious respiratory and circulatory depression than group II (P<0.05).</p><p><b>CONCLUSION</b>Doxapram may attenuate respiratory and circulatory depression during anesthesia with remifentanil given by TCI combined with propofol in painless artificial abortion, and provide comparable anesthetic efficacy.</p>

Determination of methamphetamine in whole blood by capillary zone electrophoresis after solid phase extraction / 法医学杂志

OBJECTIVE@#To develop a specific CZE method for the determination of methamphetamine in whole blood after solid phase extraction.@*METHODS@#With the doxapram as internal standard, Oasis column was used to extract drugs from whole blood and the sample was analysized by CZE.@*RESULTS@#The method showed excellent linearity and the linear correlation coefficient was 0.994. The relative standard deviation for between-day and within-day were 5.31% and 2.22%, respectively.@*CONCLUSION@#The method is effective, simple, reliable and has been used in the determination of methamphetamine in whole blood.

Analysis of 37 drugs in whole blood by HPLC after solid phase extraction / 法医学杂志

OBJECTIVE@#To develop a specific, sensitive, reproducible SPE-HPLC method for the determination of 37 drugs in whole blood.@*METHODS@#With the doxapram as internal standard, Oasis column was used to extract drugs from whole blood. Two kinds of mobile phases were used in this study. Separations were achieved by a LiChrospher 100 RP-C18 (250 mm x 4.0 mm x 5 microm) column kept at 50 degrees C, the DAD detector was set at 230 nm and 250 nm.@*RESULTS@#The limit of detection were 1-30 ng/mL. The method showed excellent linearity and the linear correlation coefficient was > or =0.997 98. The relative standard deviation for between-day and within-day assay were <10%.@*CONCLUSION@#The method is effective, simple, reliable and has been used in real cases.

The Effect of Doxapram Hydrochloride on the Ventilation Responses during General Anesthesia with Volatile Agent by Laryngeal Mask Airway / 대한마취과학회지

BACKGROUND: Inhalation anesthetics are known to depress ventilatory response to hypercapnea. Doxapram hydrochloride is an analeptic drug, which acts as a respiratory stimulant via peripheral and central chemoreceptors. Although the postoperarive infusion of doxapram hydrochloride is known to attenuate the impairment of respiratory function, no report is available on respiratory response to this drug when applied during anesthesia. Therefore, the present study aimed to evaluate the effect of doxapram hydrochloride on respiratory function during anesthesia. METHODS: Sixty adult patients undergoing operation under spontaneous ventilation via laryngeal mask airway (LMA) were randomly categorized into 3 groups: A control group, which received 5% dextrous infusion, and two groups in which patients were infused with doxapram hydrochloride (0.5 or 2 mg/kg/hr) starting 15 min after commencement operation. Anesthesia was maintained with 1 MAC sevoflurane - 4 L N2O - 2 L O2 under spontaneous ventilation via LMA. Tidal volume (VT), respiratory rate (RR), and arterial carbon dioxide tension (PaCO2) were measured just before and 15 min after the induction of anesthesia, 15 min after the start of operation and 15, 30, 45, and 60 min after the start of doxapram hydrochloride infusion. RESULTS: Measured values of RR and PaCO2 were significantly elevated during anesthesia venous those measured just before the induction of anesthesia in all groups. VT was significantly reduced during anesthesia venous just before the induction of anesthesia in all groups. All percent changes of VT, RR and PaCO2 were similar all any measurement times, and showed no significant changes after the infusion of doxapram hydrochloride in all groups. CONCLUSIONS: Intraoperative doxapram hydrochloride treatment did not produce any significant respiratory response improvement during 1 MAC sevoflurane anesthesia.

comparison among Doxapram, Nulbuphine and Meperidine for treatment of postanesthetic shivering

Postanesthetic shivering [PS] is distressing for patients and may induce a variety of complications. We carried out our study to evaluate the value of Doxapram, Nulbuphine and Meperidine for treating PS. 80 patients were included in the study who undergone general anesthesia for routine general orthopedic or gynecologic surgery and developed shivering within 10 minutes of admission to the recovery room where they are divided into 4 groups; each of 20 patients classified as follows: Group 1 [n = 20] placebo saline group [received i.v. saline]; Group 2 [n = 20] Doxapram group [received 1.5 mg/kg i.v.] Group 3 [n = 20] Nulbuphine group [received 0.08 mg/kg i.v.]; Group 4 [n=20] Meperdine group [received 0.4 mg/kg i.v.]. Treatment that stopped shivering was considered to have been successful. The results demonstrated that 5 min. after treatment with Doxapram, Nulbuphine and Meperidine provided rapid and potent anti-shivering effect on PS, with high response rate of 75%, 80% and 85%, respectively compared with those of placebo saline [0%] [p < 0.01]. 15 minutes after injection, the response rates of Doxapram, Nulbuphine and Meperidine were 80%, 85% and 90%, respectively compared with 15% in the saline group. 30 minutes after injection, the response rates of Doxapram, Nulbuphine and Meperidine 85%, 90% and 95%, respectively compared with 20% in the saline group. We concluded that nulbuphine and meperidine prevent PS but meperidine is superior to both Doxapram and Nulbuphine and Nulbuphine provides a similar rapid and potent shivering effect so it may be an alternative to meperidine for treating postanesthetic shivering

Anesthetic Experience of a Patient with Chronic Hypoventilation Syndrome: A case report / 대한마취과학회지

Alveolar hypoventilation exists by definition when arterial PaCO2 increases above the normal range of 37 to 42 mmHg, but in clinically important hypoventilation syndromes PaCO2 is generally in the range of 50 to 80 mmHg. The management of chronic hypoventilation must be individualized to the patient's particular disorder, circumstances and need. This is a case report of anesthetic management of a 63-year-old woman with central alveolar hypoventilation (CAH) secondary to cerebral infarction. For hip surgery epidural anesthesia with 0.5% bupivacaine was performed and doxapram was applied to maintain respiratory drive. The anesthetic experience with a brief review of literature is reported.

Clonidine, doxapram and ondansetron for treatment of postoperative shivering

Postanethetic shivering is a rhythmic movement, predominantly involving the upper limbs, neck and jaw, that occurs in 5-70% of patients recovering from general anesthesia. Postanethetic shivering may produce complications especially in patients with coronary artery disease, secondary to increased oxygen consumption, cardiac output, carbon dioxide production and circulating catecholamines and decrease mixed venous saturation. 60 patients classified as ASA physical status I and II were divided, in recovery room, into 3 groups [n=20] to treat postoperative shivering. Group [1] received clonidine 75 micro g, group [2] doxapeam 60mg and group [3] ondanosetron 8mg Temperature was recorded at the start of surgery, lowest temperature during operation and temperature at the end of surgery. In recovery room shivering score was recorded before drug and 5, 10, 20 and 30min after. Heart rate, mean blood pressure and temperature were measured at arrival, 5, 10, 20, 30, 60 and 90 min after. Side effects as tachycardia, bradycardia, hypertension, hypotension, sedation, persistence of shivering, more than grade II, for more than 5 min and recurrence of shivering after 20 min were recorded. Shivering score, allover the study, decrease significantly in group [1] compared to group [2] and [3], also decrease in group [2] compared to group [3]. Hypotension, bradycardia and sedation were associated with clonidine. Hypertension and tachycardia were associated with doxapram. Persistence of shivering was more in group [3] while reoccur of shivering was more in group [2]. Clonidine, doxapram and ondanosetron can be used to treat postoperative shivering, but clonidine is superior to doxapram and ondanosetron. Side effects of clonidine like hypotension, bradycardia and sedation must be in consideration especially in haemodynamically instable patients. Doxapram can be used in hypotensive patients, but avoid it if there is hypertension or tachycardia. On the other side ondanosetron has innocuous effects on the cardiovascular system. Persistence of shivering is more with ondanosetron while reoccurs, after 20min, is more with doxapram

A Comparison of Effectiveness Correlated with Different Doses of Doxapram in the Treatment of Post-Anesthetic Shivering / 대한마취과학회지

BACKGROUND: Although post-anesthetic shivering may be a temporary phenomenon, it leads to detrimental effects such as increased oxygen consumption, hypoxemia, and difficulty in monitoring. Doxapram is a relatively new treatment for post-anesthetic shivering, but there have been few reports about its minimum effective dose. The purpose of this study was to find the minimum dose of doxapram which would show an antishivering effect. METHODS: Sixty patients who had developed post-anesthetic shivering were divided into six groups of ten patients each. The groups were divided into a control group, which received normal saline, and the doxapram groups, which received five different doses of doxapram (0.15, 0.2, 0.5, 1.0, 1.5 mg/kg). The antishivering effect (2, 5, 10, 15 minutes after treatment), blood pressure, heart rate and temperature were compared among the groups. RESULTS: There was a significant difference in antishivering effect between the group which received normal saline and the groups which received doxapram; however, there was no significant difference within the groups which received doxapram. CONCLUSIONS: We conclude that the dose of doxapram required to achieve an antishivering effect is much less than that currently in use.

Comparison of Effectiveness of Meperidine, Doxapram, and Fentanyl on Postanesthetic Shivering / 대한마취과학회지

BACKGROUND: Shivering is a common postanesthetic complication. Because all shivering patients feel uncomfortable and increase oxygen consumption, various attempts have been made to prevent its occurrence or to control it. Among the pharmacological methods of treating shivering, meperidine has been known to be the most effective. This study was designed to evaluate whether there was any difference among meperidine, fentanyl, doxapram and normal saline in the treatment of post-anesthetic shivering. METHODS: Forty patients (ASA class I or II) who showed postoperative shivering were randomly assigned into four groups (n=10): Normal saline group: normal saline 5 ml, Doxapram group: doxapram 1.5 mg/kg, Meperidine group: meperidine 25 mg, Fentanyl group: fentanyl 25 microgram. And all patients received routine care: oxygen by T-piece and heat-reflective blanketrol (cincinati Subzero, U.S.A.). Evaluation of the state of shivering was done every 5 minutes from the beginning of the treatment by the same investigator who had injected the drugs intravenously for treatment of shivering. The age, sex, weight and duration of surgery were recorded. RESULTS: There were no significant statistical differences in age, sex, weight and duration of surgery among the four groups. By 5 minutes, 90% of doxapram group and 30% of meperidine group had stopped shivering. By 10 minutes, 90% of doxapram group and 70% of meperidine group had stopped shivering. But in fentanyl and normal saline group, only 20% had stoppd shivering by 10 minutes. CONCLUSIONS: We conclude that both meperidine and doxapram are effective on post-anesthetic shivering. In cases of patient with respiratory depression, doxapram is especially effective because it stimulates the respiratory center.

Compatibility of Neonatal Parenteral Nutrient Solutions with Commonly Used Drugs during Y-site Delivery in NICU

PURPOSE: Because vascular access sites in neonates are limited, intravenous (IV) medications must often be mixed with maintenance fluids, including parenteral nutrient (PN) solutions. This study was done to determine whether IV medications commonly prescribed in the neonatal in- tensive care unit (NICU) are compatible with the two neonatal PN solutions. METHODS: The compatibility of neonatal PN solutions and selected other drugs during Y-site delivery was evaluated. Secondary drugs were administered at selected concentrations, rates and delivery by method commonly used at the NICU. Drugs administered by syringe pump over 30min : amikacin, cefotaxime, ceftriaxone, piperacillin, phenytoin, aminophylline, ceftazidime, fluconazole, indomethacin. Drugs administered by IV push : ampicillin+sulbactam, penicillin G potassium, NaHCO3, ranitidine, epinephrine, furosemide, dexamethasone. Drugs administered by IV infusion for at least 60min : acyclovir, amphotericin B, vancomycin, dobutamine, dopamine, doxapram. After each test, the Y injection site and tube below the Y injection site were visually inspected for precipitation and color change. If no particles or color change was detected, the solution was tested and analyzed by a liquid borne particle analyzer (LBPA). RESULTS: White precipitate formed immediately after Y-site administration : phenytoin, aminophylline (undiluted solution), ampicillin+sulbactam (undiluted solution). Number of particles observed with LBPA exceeded the KP guideline limit immediately after Y-site administration and white precipitate formed after 3-4 hour : ceftriaxone, NaHCO3 (1 : 2 diluted solution). CONCLUSION: These results revealed that several lV drugs prescribed in NICU formed precipitate and had a color change, when mixed with neonatal TPN solutions.

Compatibility of Neonatal Parenteral Nutrient Solutions with Commonly Used Drugs during Y-site Delivery in NICU

PURPOSE: Because vascular access sites in neonates are limited, intravenous (IV) medications must often be mixed with maintenance fluids, including parenteral nutrient (PN) solutions. This study was done to determine whether IV medications commonly prescribed in the neonatal in- tensive care unit (NICU) are compatible with the two neonatal PN solutions. METHODS: The compatibility of neonatal PN solutions and selected other drugs during Y-site delivery was evaluated. Secondary drugs were administered at selected concentrations, rates and delivery by method commonly used at the NICU. Drugs administered by syringe pump over 30min : amikacin, cefotaxime, ceftriaxone, piperacillin, phenytoin, aminophylline, ceftazidime, fluconazole, indomethacin. Drugs administered by IV push : ampicillin+sulbactam, penicillin G potassium, NaHCO3, ranitidine, epinephrine, furosemide, dexamethasone. Drugs administered by IV infusion for at least 60min : acyclovir, amphotericin B, vancomycin, dobutamine, dopamine, doxapram. After each test, the Y injection site and tube below the Y injection site were visually inspected for precipitation and color change. If no particles or color change was detected, the solution was tested and analyzed by a liquid borne particle analyzer (LBPA). RESULTS: White precipitate formed immediately after Y-site administration : phenytoin, aminophylline (undiluted solution), ampicillin+sulbactam (undiluted solution). Number of particles observed with LBPA exceeded the KP guideline limit immediately after Y-site administration and white precipitate formed after 3-4 hour : ceftriaxone, NaHCO3 (1 : 2 diluted solution). CONCLUSION: These results revealed that several lV drugs prescribed in NICU formed precipitate and had a color change, when mixed with neonatal TPN solutions.

A case of acute coma & respiratory arrest in Wernicke's encephalopathy caused by malnutrition / 대한내과학회지

We shoud give attention to Wernicke's encephalopathy as a cause of sudden coma & respiratory arrest in patients, who are not usually suspected to develop the disorder and empirical treatment with thiamine in cases of coma of unknown cause is recommended. Respiratory stimulants, doxapram & aminophylline have an effect in assisting ventilatory weaning in patient with central hypoventilation as a complication of acute Wernicke's encephalopathy No previous reports where doxapram had been used to assist weaning from mechanical ventilation in adults were noted. Nor has newly developed central hypoventilation been identified as an impediment to weaning in literature to date in Korea. We reported a rare case of Wernicke's encephalopathy caused by poor oral intake & inadequate nutritional suppliment after car accident, showing acute coma & respiratory arrest and treated adequately by thiamine replacement & mechanical ventilation with respiratory stimulant.

The Effects of Doxapram on the Pulmonary Function during Total Intravenous Anesthesia with Propofol According to Nalbuphine Pretreatment / 대한마취과학회지

BACKGROUND: Total intravenous anesthesia with propofol can cause respiratory depression and apnea especially during induction of anesthesia. To study the possibility of reversal of respiratory depression during anesthesia with propofol, pretreated with nabuphine or not, the respiratory effects of doxapram to spontaneously ventilating patients were investigated. METHODS: Patients were divided into 4 groups - saline-propofol-saline group (SPS), saline-propofol- doxapram group (SPD), nalbuphine-propofol-saline group (NPS), and nalbuphine-propofol-doxapram group (NPD). After saline or nalbuphine pretreatment, anesthesia was induced with propofol and then doxapram or saline was intravenously injected. Apneic time interval, blood pressure, heart rate, respiratory rate, minute ventilation, end tidal CO2 partial pressure and oxygen saturation were measured in every minutes during induction of anesthesia. Percent changes of each values were compared. RESULTS: There is no differences in apneic time intervals in each groups. The percent change of first minute ventilation in SPD group after doxapram injection unchanged significantly compared with those depressions of SPS, NPS and NPD group (p<0.05). Respiratory rates increased in SPD and SPS groups after laryngeal mask insertion. There is no differences in minute ventilation, respiratory rate and end-tidal CO2 concentration between nalbuphine pretreated groups regardless of doxapram injection. CONCLUSIONS: Doxapram has effect in increasing minute ventilation after propofol induction within first few minutes, but it cannot reverse respiratory depression during propofol induction pretreated with nalbuphine.

Effect of Doxapram on the Recovery from Vecuronium from Vecuronium of Mivacurium-induced Neuromuscular block in the Rabbit / 대한마취과학회지

Doxapram as a potent respiratory stimulant is one of attempts to solve respiratory problem and has been known to be effective for many years. But one study suggested that the presence of doxapram retarded neostigmine-induced antagonism of vecuronium effect. So we studied the effect of doxapram on the reverse of neuromuscular block when doxapram was injected with different dose. 60 rabbits were divided into 6 groups. Vecuronium was used in Group 1~3 and Mivacurium was used in Group 4~6 as a muscle relaxant. When the first twitch of TOF response reappeared from the complete block with a muscle relaxant (T1 onset), we administered neostigmine 0.05 mg/kg and saline 0.3 ml i.v. in Group 1, 4(VS, MS), neostigmine 0.05 mg/kg and doxapram 0.5 mg/kg i.v. in Group 2, 5(VDP1, MDP1), and neostigmine 0.05 mg/kg and doxapram 3 mg/kg i.v. in Group 3, 6(VDP2, MDP2). Two recovery time, from T1 onset to T1 25% and from T1 25% to T1 75%, and TR(ratio ; T4 twitch/T1 twitch) at T1 75% were measured. For the hemodynamic effect of doxapram, Blood pressure, heart rate and arrythmia were observed before and after doxapram injection too. The results are as follows. 1) Recovery time from T1 onset to T1 25% are 2'30"+/-0'29"(min'sec") in VS, 3'07"+/-0'4l"(minsec") in VDPl, 1'49"+/-0'17"(min'sec") in VDP2, 2'34"+/-0'17"(min'sec") in MS, 2'41"+/-0'25"(min'sec") in MDP1, 1'52"+/-0'39"(min'sec") in MDP2. 2) Recovery time from T1 25% to T1 75% are 4'58"+/-0'52"(min'sec") in VS, 6'10"+/-1'17"(min'sec") in VDP1, 3'38"+/-0'33"(min'sec") in VDP2, 4'38"+/-'0'57"(min'sec") in MS, 5'10"+/-0'55"(min'sec") in MDP1, 3'15"+/-0'38"(min'sec") in MDP2. 3) TR at T1 75% are 76.6+/-7.7% in VS, 82.4+/-3.4% in VDP1, 83.8+/-4.5% in VDP2, 81.4+/-2.3% in MS, 89.8+/-2.3% in MDP1, 89.8+/-1.5% in MDP2. 4) Heart rate, cardiac rhythm, systolic and diastolic pressure before and after doxapram injection were not significantly changed. In conclusion, simultaneous administration of neostigmine and low dose doxapram delayed recovery from the neuromuscular block, but high dose doxapram did not.